VOLUME 3
Interim Measures Workplanfor Soil Cleanup :
DTSC and CEQA Document s
Former Sodium Disposal FacilitySanta Susana Field Laboratory
Assembled For :
Rocketdyne Propulsion and PowerBoeing North American, Inc .
6633 Canoga AvenueCanoga Park, California 9130 9
IT,A Memher of The IT Group
Assembled By :
IT Corporation650 Sierra Madre Villa, Suite 204
Pasadena, California 9110 7
March 17, 2000
HDMSP00028117
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VOLUME 3APPENDICES
Appendix L DTSC Approval Letter and ResponseComments
Appendix M CEQA Initial Study
Appendix N CEQA Notice of Determination andMitigated Negative Declaratio n
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91B-2-99
HDMSP00028119
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Appendix L
DTSC Approval Letter and Response to Comments
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4,
Winston H. HickoxAgency Secreta ryCalifornia Environmental
Protection Agency
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11
Department of Toxic Substances Contro l
Edwin F . Lowry, Director10151 Croydon Way, Suite 3
Sacramento , California 95827-2106
December 14, 1999
Mr. David W. DasslerEnvironmental RemediationRocketdyne Propulsion & Power6633 Canoga Avenu ePost Office Box 7922Canoga Park , California 91309-7922
D.w Dp st- R
DEC 161999
APPROVAL OF INTERIM MEASURES WORKPLAN , FORMER SODIUM DISPOSALFACILITY, SANTA SUSANA FIELD LABORATORY , VENTURA COUNTY,CALIFORNIA , EPA ID NO . CAD 000629972
Dear Mr. Dassler :
Gray DavisGoverno r
The California Environmental Protection Agency, Department of Toxic SubstancesControl (DTSC) has made a decision to approve the Interim Measures Workplan for theFormer Sodium Disposal Facility (FSDF) located in the west end of the Santa SusanaField Laboratory, Simi Hills, California .
On July 20, 1999, DTSC issued a public notice to request public comments on the DraftInterim Measures Workplan dated July 9, 1999 and the Draft Mitigated NegativeDeclaration for the FSDF . The public comment period was open throug hAugust 19 , 1999 . A public hearing was held on July 28 , 1999 , at the Radisson HotelSimi Valley, to receive oral and wri tten comments for the record. Comments receivedduring the public comment period were considered before DTSC made its approvaldecision . DTSC has prepared a Response to Comments document which containsDTSC 's responses to the comments received on both the Interim Measures Workplanand the Draft Mitigated Negative Declaration .
After considering the comments received, DTSC made changes to the Draft InterimMeasures Workplan. These changes are outlined in Attachment A, and shall beincorporated into the final Interim Measures Workplan . A copy of the Response toComments document is enclosed for your records . You may instruct your contractor tobegin activities .
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HDMSP00028121
Mr. David W. DasslerDecember 14, 1999Page 2
If excavation activities are to proceed during the upcoming winter season , an HOPEliner cover must be maintained as a contingency. Existing emergency controls in placeto remove water which collects on or beneath the HOPE liner during rain events shallbe continued until the clay backfill cover is installed and the interim measu res project iscomplete . During rainfall events , the excavation activities will cease and theimpoundments covered with the HDPE liner to minimize possible spread ofcontaminants . You are required to provide DTSC with a schedule of activitiesidentifying the tasks and the dates of field activities one week prior to commencing withany excavation or removal activities .
As you are aware, DTSC would like to proceed with completion of characterization forthe FSDF as expeditiously as possible . Prior to backfilling the excavation and no laterthan 60 days from the date of this letter, please submit an Infiltration MonitoringWorkplan to DTSC for review. The infiltration monitoring probes should be capable ofevaluating moisture infiltration rates through the backfill soils . Please submit an RFIworkplan for contaminant characterization (including characterization of the,vadosezone) no later than 120 days from the date of this letter .
A copy of the final administrative record for the Interim Measures Workplan approval isavailable for review at our Glendale Office.
If you have any questions , please feel free to contact Gerard Abrams at(916) 255-3600.
Sincerely,
James M. Pappas , P.E., ChiefLand Disposal BranchHazardous Waste Management Progra m
Enclosure s
cc: Mr. Joe Lyou (w 3 copies)Executive DirectorRocketdyne Cleanup Coalitiondo Committee to Bridge the Gap1637 Butler Avenue , Suite 203Los Angeles, California 90025
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HDMSP00028122
• Mr. David W . DasslerDecember 14, 1999Page 3
0
cc: Ms . Kim Rener (w 1 copy)The Boeing Company, Rocketdyne6633 Canoga AvenuePost Office Box 7922Canoga Park, California 91309-7922
Mr. Tom Kelly, Project Manager (w 1 copy)U.S. Environmental Protection AgencyWaste Management Division75 Hawthorne Stree tSan Francisco, California 94105
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Mr. Roger Lupo (w 1 copy)Radiologic Health Branch601 N. 7th Street (MS 178)Sacramento , California 9581 4
Mr. Mike Lopez (w 1 copy)Oakland Operations Office1301 Clay Street, N825Oakland , California 9461 2
Mr. Steve Cain (w 1 copy)Public Participatio nDepartment of Toxic Substances Control1011 N. Grandview Avenu eGlendale, California 9120 1
Mr. T.R. Hathaway (w 1 copy)Human & Ecologic Risk DivisionDepartment of Toxic Substances Control301 Capital Mall, 3rd Floo rSacramento , California 9581 3
Mr. Gerard Abrams (w 1 copy )Senior Hazardous Substances Engineering GeologistLand Disposal Branc hDepartment .of Toxic Substances Control10151 Croydon Way, Suite 3Sacramento, California 95827-2106
• Mr. David W. DasslerDecember 14, 1999Page 4
cc: Glendale File Room (w 2 copies)do Mr. Stephen BaxterSenior Hazardous Substances EngineerDepartment of Toxic Substances Control1011 North Grandview AvenueGlendale, California 9120 1
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ATTACHMENT A
LIST OF CHANGES TO BE MADE FROM DRAFT INTERIM MEASURES DATEDJULY 9, 1999 TO FINAL INTERIM MEASURES WORKPLAN
1 . Section 1 . 1 .4 will be modified as follows :
CEQA compliance has been reviewed by DTSC and a Mitigated NegativeDeclaration finding made for this Interim Measure
2. Section 4.1 .3.3 . 2 (paragraph 4) will be modified as follows :
One randomly located documentation sample will be collected on each samplegrid (established in the FSDF Characterization Report, refer to Section 2.1.3 andFigure 3-1 of this workplan ) from the scarified bedrock of the excavation bo ttom.If field conditions warrant or if directed by a DT geologist biased sample willbe collected at locations of staining or obse rvable signs of contaminationBedrock samples will be taken using a clean steel hammer to extract chips fromthe bedrock surface . The bedrock samples will be placed in clean containersprovided by the laboratory.
3. Section 4.1 .3.3.3 Sampling and Analysis Procedures - Waste Characterization,Paragraph 1, will be modified as follows :
Soils will be collected from the excavator bucket during bin loading by driving thestainless steel sampling sleeve directly into the soil. The sampling sleeve willthen be retrieved, capped, and labeled. A scoop must not be used to transferthe soil from the excavator bucket into the sampling sleeve .
4.. Section 4 .3.3.1 .2 Identification and Testing of Backfill Sources, will be modifiedto include the following statement :
If it becomes necessa ry to import backfill soil, the imported soil must be ofsimilar soil type to the onsite borrow source soils , and meet or exceed thepermeability specifications of 4 x 10~ cm /s when compacted to 90 percent.
5. Section 4.3.3.1 .4 Backfi ll Placement and Grading , Paragraph 2, will be modifiedas follows:
Soil will be placed and compacted within 2 percent of optimum moisture content,to meet 4x10-0 cm/s permeability.
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HDMSP00028125
ATTACHMENT A, INTERIM MEASURES WORKPLA N
6. Section 4.3.3.3 .3 Backfill Placement Inspection and Testing , Paragraph 2, will bemodified as follows:
At a minimum . 3 density and moisture content tests will be performed per 6-inchlift in the lower ball materials .
The compacted backfill will be tested to assess in-situ permeability, followinginstallation and compaction of the low permeability backfill .
7. During excavation and backfilling activities , the following dust control measuresshall be observed, as requested by the Ventura County Air Pollution ControlBoard in a le tter dated August 24, 1999:
(a) All clearing, grading , earth moving , or excavation activities shall ceaseduring periods of high winds ( i .e ., greater than 15 miles per houraveraged over one hour) to prevent excessive amounts of fugitive dust.
(b) All trucks that will haul excavated or graded material off-site shall complywith State Vehicle Code Section 23114 regarding the prevention of suchmaterial spilling onto public streets and roads.
(c) All unpaved on-site roads shall be periodically watered or treated withenvironmentally-safe dust suppressants to prevent excessive amounts ofdust.
(d) All active portions of the site shall be either periodically watered ortreated with environmentally -safe dust suppressants to prevent excessiveamounts of dust .
(e) On-site vehicle speeds shall not exceed 15 miles per hour .
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HDMSP00028126
•
RESPONSE TO COMMENTSon the
DRAFT INTERIM MEASURES WORKPLAN
PROPOSED MITIGATED NEGATIVE DECLARATION
for
THE FORMER SODIUM DISPOSAL FACILITY
SANTA SUSANA FIELD LABORATORY
EPA ID NO: CAD 000629972
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TABLE OF CONTENT S
L INTRODUCTION . . . . . . . . . . . . . I
II. REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
III. RESPONSE TO COMMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1 . Infiltration through fractured bedrock , Protectiveness of backfill , and need forRCRA-like cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2. CEQA Initial Study/EIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3. Cleanup and Abatement Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4. Mercury Cleanup Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
5 . Human Health Risk Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
6. Ecologic Risk Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
7. Verification Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8 . Waste Categorization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
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9. Borrow Source and Grading Permit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
10. Airborne Dust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
11 . Radiation Screening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
12. Truck Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
13 . Community Notification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
14. Background Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
15. Community Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
16. Transportation Route . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
17. General Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
18. List of changes made from draft to final IMWP . . . . . . . . . . . . . . . . . . . . . . . . . 85
HDMSP00028128
• Former Sodium Disposal Facili ty December 1999Response to Comments Page I
L INTRODUCTION
The Santa Susana Field Laboratory (SSFL) is located in the Simi Hills of Eastern VenturaCounty . The Former Sodium Disposal Facility (FSDF) is located at the western end of the SSFLin an area known as Area IV where energy-related research was conducted by the EnergyTechnology and Engineering Center (ETEC) on behalf of the Department of Energy .
During the period from 1950 through 1973, Rockwell International Corporation, throughits Rocketdyne Division, and various predecessor organizations conducted rocket testing andenergy-related research at the SSFL. In 1996 , the Rocketdyne Division (Rocketdyne ) became apart of Boeing North American, Inc . (Boeing ), and Boeing , through Rocketdyne, currentlyoperates the SSFL and has undertaken SSFL cleanup activities .
The FSDF was used extensively from 1956 to 1976 for disposal of sodium and sodiumpotassium (NaK) by exothermic reaction with water and other combustible materials includingterphynal coolants used for the reactor programs (Sodium Reactor Experiment and SNAP) . Theproposed Interim Measures Workplan specifies the removal of approximately 3,200 cubic yards ofsoil and sediment from the Upper Pond and Western Area of the FSDF and the drainage channelsbelow the ponds .
On May 18 , 1998, Rocketdyne submitted an initial draft Interim Measures Workplan forthe FSDF . Based on the Department of Toxic Substances Control (DTSC) review, the draftInterim Measures Workplan has been revised several times . On July 15 , 1999 , DTSC determinedthat the draft FSDF Interim Measures Workplan was complete and acceptable for public notice .DTSC requested public comments on the proposed Interim Measures Workplan and CaliforniaEnvironmental Quality Act (CEQA) documents , and a Public Hearing was held at theRauisson Hotel in Simi Valley on July 28 , 1999. The public comment period was open froruJuly 20, 1999 to August 19, 1999 .
Written comments were received during the public comment period and verbal commentsduring the Public Hearing . This Response to Comments document summarizes and responds toall relevant comments received by DTSC during the comment period . Some comments presentedin this document are directly quoted from the public while other recurring comments weresummarized in a representative comment. Some comments were also edited for clarity . Eachcomment has been assigned a unique number between 1 and 133. Throughout this documen4references to other responses may be given in lieu of or as an addition to the response to thatparticular comment . Every effort has been made to ensure that the references are accurate andresult in a more comprehensive response .
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HDMSP00028129
Former Sodium Disposal Facility December 1999Response to Comments Page2
OVERVIEW OF COMMENTS
Briefly summarized , comments received during the public comment period can be groupedinto the following : 1) comments which questioned whether the proje ct would be protective ofgroundwater, 2) comments which questioned the adequacy of the CEQA review, and3) comments which requested clarification on, or questioned various aspects of the workplan,including transportation route, community notification, and verification sampling .
The intent of the proposed interim measures at the FSDF is to remove the dioxin, PCB,and mercury contaminated soil that has a potential to continue to migrate into the drainages belowthe impoundments and pose a risk to human and/or ecologic receptors. The investigation andcleanup of groundwater is being addressed concurrently as part of the site-wide groundwatercharacterization and remediation at the SSFL . The decision to remove the remaining soilcontamination as an interim measure was weighed against the risks to health and environmentwhich may occur if removal of the contaminated soil is deferred until a detailed characterizationstudy of remaining contamination in the bedrock beneath the impoundment has been completed,and a remedy has been selected . In DTSC's view, greater environmental and human healthprotection will be achieved by immediate removal of the contaminated soils, rather than delayremoval until characterization of the bedrock - a process which may take one or two additionalyears - is complete . The interim measure will reduce the immediate risk of exposure to PCBs,dioxins, and mercury contaminated soils in the drainage channels . The proposed interim measureis consistent with and can be integrated with any longer term corrective action for the FSDF .
HOW WILL REMAINING CONTAMINATION IN THE GROUNDWATER ANDBEDROCK BE ADDRESSED?
Within 60 days of approval of the Interim Measures Workplan, Boeing will submit anInfiltration Monitoring Workplan to DTSC for review . Probe locations will be based on fieldobservations and mapping of bedrock following removal of contaminated soils from th eimpoundments. The infiltration monitoring probes will be used to evaluate moisture infiltrationrates and lateral flow-through in the soils beneath the FSDF.
Within 120 days of approval of the Interim Measures Workplan, Boeing will submit anRCRA Facility Investigation (RFI) Workplan to evaluate the extent and nature of contaminationin the fractured bedrock beneath the FSDF .
Data collected as part of the RFI investigation will be incorporated into a CorrectiveMeasures Study (CMS) for the FSDF . The scope and substance of the CMS will be focused to fitthe complexi ty of the site, including the nature and extent of contamination in the fracturedbedrock beneath the FSDF . The objective of the CMS is to develop and evaluate correctivemeasure alternative(s) that may be utilized by the facility to address hazardous waste releases atthe FSDF. Treatability studies and on-site pilot scale studies may be necessary to evaluate
potentially applicable technologies, especially innovative technologies for the site . One of the
HDMSP00028130
Former Sodium Disposal Facility December 1999Response to Comments Page3
primary objectives of any final remedy selected for a site is to stop further environmentaldegradation by controlling or eliminating further releases that may pose a threat to human healthand the environment . Unless source control measures are taken , efforts to cleanup releases maybe ineffective or, at best , will essentially involve perpetual cleanup . Therefore, it is DTSC'sposition that the proposed interim measure will provide an effective source control by removingthe contaminated soil at the site , although additional investigative work and source controlmeasures to address the contamination in the bedrock itself may be essential to ensure thelong-term effectiveness of the corrective action effo rt .
Based on the evaluation of the corrective measures alte rnatives presented in the CMS andupon approval of the CMS Report, DTSC will initiate remedy selection for the FSDF and willselect a final remedy for the site after considering public comments on the Statement of Basis .The Statement of Basis is a public pa rticipation document which describes the basis for DTSC'stentative remedy selection and identifies the media cleanup standards . The Statement of Basisdesc ribes the proposed remedy , but does not select the final remedy for a facility . As statedabove, the final remedy will be selected after considering all public comments . This approachallows DTSC to provide a comprehensive technical justification for the proposed remedy andallows for additional information to be considered during the public comment period before a finalremedy is selected . A final remedy for the FSDF may consist of a RCRA-like cap, vaporextraction or thermal treatment systems , or other alternative technology or combination oftechnologies . However, it is DTSC' s position that this decision should be made only afteradequate assessment of the nature and extent of contamination from the FSDF and only a fterproper evaluation of corrective measures alternatives to ensure that the proposed measure isprotective of human health and the environment .
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HDMSP00028131
Response to Comments
II. REFERENCES
Former Sodium Disposal Facility December 1999Page 4
1 . Transcripts of public hearing in the matter of"Proposed Interim Measures and CEQANegative Declaration for Santa Susana Field Laboratory (former Sodium DisposalFacility), Simi Valley, CA," held on July 28, 1999 , reported by Barney, Ungermann &Associates ; 95 pages .
a. Exhibit 1 : Testimony from Ms. Schutz[See Comments 72, 73, 74]
b. Exhibit 2 : Testimony from Ms. Norma Bishop[See Comments 78, 106, 107, 108, 109, 110, 111, 112, 113]
c. Exhibit 3 : Testimony from Ms. Laura Held[See Comments 59, 92, 93, 114]
•Exhibit 4 : Testimony from Mr . Jerry Ruskin[See Comments 72, 73, 74]
e. Exhibit 5 : Testimony from Ms . Barbara Johnson[See Comments 27, 60 , 68, 75, 76, 77] .
f. Exhibit 6 : Testimony from Dr . Joseph Lyou[See Comments 34, 35, 102]
8• Exhibit 7 : Testimony from Ms . Laura Plotkin[See Comments 49, 70]
h. Exhibit 8 : Testimony from Ms . Bonnie Klea[See Comments 79, 85]
i. Exhibit 9 : Testimony from Ms . Rosemary Woodlock[See Comment 36]
J .
k .
Exhibit 10: Testimony from Ms . Laurie Peyton[See Comments 80, 81, 82, 86]
Exhibit 11 : Testimony from Mr. Wendell Ho[See Comments 94, 95]
1 . Exhibit 12 : Testimony from Dr. Lit[See Comments 50, 58]
• Former Sodium Disposal Facility December 1999Responseto Comments Page5
m. Exhibit 13 : Testimony from Ms. Marie Mason[See Comments 69, 87, 88, 89, 90, 91]
[The, following were written comments received during the public comment periodJ
2. Letter from Joseph K. Lyou, Ph.D., August 19, 1999 , 10 pages.[See Comments 1-14, 28-30, 39-43, 99-101]
3 . Written comments from Joseph K . Lyou, Ph.D., 3 pages .[See Comments 34, 35, 102]
4. Written comments from Philip B . Chandler, August 18 , 1999, 8 pages.[See Comments 15-26, 31-33, 38, 42, 44, 45, 46, 47, 51-57, 61-67, 71, 103, 104]
5 . Public Comment Form from R. D. Giesler, July 28, 1999, 1 page .[See Comment 117]
6. Letter from George Rembaurn, August 1, 1999, 1 page .[See Comment 36]
Public Comment Form from Estelle Lit, Ed . D, 1 page .[See Comments 118]
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8. Public Comment Form from Ryan, July 28 , 1999, 1 page .[See Comment 119]
9. Public Comment Form from Donald and Alice Goldsobel , July 28, 1999, 1 page .[See Comment 120]
10. Public Comment Form from Larry A. Davis, July 28, 1999, 1 page.[See Comment 121]
11 . Public Comment Form from Eita E . Staszak, July 28, 1999, 1 page .[See Comment 123]
12. Public Comment Form from William M. Brace, July 28, 1999, 1 page.[See Comment 124]
13 . Public Comment Form from Krista Vretenar, July 28, 1999, 1 page .[See Comment 125]
•Former Sodium Disposal Facility Deoanber 1999Response to Comments Page 6
14. Public Comment Form from Richard Schmorleitz and Linda Nelson , July 28, 1999,1 page . [See Comment 126]
15 . Public Comment Form from Richard Rice , July 28, 1999, 1 page .[See Comments 97, 127]
16. Public Comment Form from Mr . and Mrs. Scott Patton, July 28, 1999, 1 page .[See Comment 128]
17. Public Comment Form from Jack Byers, July 28, 1999, 1 page .[See Comment 129]
18. Letter (Fax) from Paula J. Neidlinger, Aug l8 , 1999, l page .[See Comment 96]
19 . Letter from Leonard H . Jacobson, Aug 10 , 1999, 1 page .[See Comment 130]
20. Letter from Michael J. Ram, July 21 , 1999,1 page .[See Comment 115]
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21 . Letter from Lee and Jeanie Krimm, August 18 , 1999, 1 page .[See Comment 96]
22 . Letter from Lee and Jeanie Krimm, August 18 , 1999, 2 page .[See Comment 96]
23 . Letter from Paula J . Neidlinger, August 17, 1999, 9 pages w/ petitions .[See Comment 96]
24. Letter from Paula 3 . Neidlinger, August 18, 1999, 1 page .[See Comment 96]
25 . Letter from Veronica Murillo, August 19, 1999 , 1 page .[See Comment 98]
26. Letter from Rosemary D . Woodlock, July 28, 1999, 3 pages .[See Comment 116]
27. Letter from Teresa Jordan, July 28, 1999, 4 pages .[See Comments 113, 132, 133]
28 . Electronic mail from Jerry Gooze , August 19, 1999, 2 page .[See Comment 96]
Former Sodium Disposal Facility Dooemba 1999Response to Comments Page 7
ILL RESPONSE TO COMMENTS
INFILTRATION THROUGH FRACTURED BEDROCK, PROTECTIVENESS OFBACKFILL, AND NEED FOR RCRA-LIKE COVER
Comment 1
The key question with the proposed interim remedial measure is : Why has DTSC retreatedfrom the more protective requirements established at earlier stages of this process? This retreathas resulted in proposed decisions that do not address or mitigate several potentially significantenvironmental impacts, impacts well recognized and described in detail in comments from DTSCto Rocketdyne . In its "Comments on the 1997 Amendment to the Former Sodium DisposalFacility Interim Remedial Measure Workplan for Soil Clean Up," attached to the DISC letterdated October 10, 1997, DTSC wrote :
All IM Workplans shall ensure that the interim measures are designed to mitigatecurrent or potential threats to human health and/or the environment , and should to theextent practicable , be consistent with the objectives of and contribute to the performanceof any remedy which may be required at the Facility. Therefore, the proposed interimmeasures must also address continued contaminant migration through the , fracturedbedrock under j~ing the FSDF.
[2 ]
Response
The measures proposed in the Intermin Measures Workplan (IMWP ) are consistent withthe objectives established in 1997 . Until such time when a characterization of the remainingcontamination beneath the impoundment is completed and final remedy is implemented, theplanned and ongoing interim measures which will help stabilize potential migration ofcontaminants through the fractured bedrock include :
1 . Replacing the contaminated soil with a low permeability clay backfill and vegetative cover .The tested hydraulic conductivity of the native backfill material is 4 x 10' cm/s, which willreduce leachate through the base to less than 98 % of precipitation. The performance ofthe clay backfiWvegetative cover design was compared , using a numerical model(LEACHM), with performance of other design options, including installation of animpermeable HDPE liner cover over the clay backfill . The clay backfill/vegetative cover
• design performed better (i .e . resulted in approximately 55% less leachate passing throughthe base) than the HDPE liner design . The improved performance of the claybackfiWvegetative cover design is due to removal of latent soil moisture by plantevapotranspiration, which cannot occur when the backfill is covered with an impermeabl e
HDMSP00028135
Former Sodium Disposal Facility December 1999Responseto Comments PageS
liner cover . This design is consistent with , and will contribute to, the performance of anyfinal remedy which may be required at the unit . The removal of contaminated soils andreplacement with clean backfill is protective of the environment and eliminates theimmediate and real threats to human health and for the environment which exist if thedioxin, PCB, and mercu ry contaminated soils remain in the impoundment until a finalremedy is selected .
•
2. The backfill cover will be engineered with a 10% grade to promote rainwater runoff. Av-ditch will be constructed to divert run-on rainwater . Even though the impoundment iscurrently tarped, water accumulates underneath the tarp. The engineered design of thebackfill will promote runoff and remove the potential for ponding of water over theimpoundment which currently exists, thereby reducing potential infiltration into the vadosezone .
3 . Continued operation of the two groundwater extraction /treatment systems at the FSDF tostabilize and remediate the plume as pa rt of the RCRA Facility Investigation (RFI). Thegroundwater treatment system removes and treats contaminated groundwater and hasstabilized spread of groundwater contamination from the FSDF.
4 . Continued monitoring of groundwater quality from the 14 groundwater monitoring wellslocated in and around the FSDF impoundment as part of the RFI . Monitoring of wells willprovide an indication of any change in water quality .
5 . Capability of adding additional extraction wells to the treatment system to stabilize theplume if a change in groundwater conditions is observed . This contingency is adequatelycovered under the corrective action process , and is therefore not being proposed orincluded in the IMWP .
6. A component of the RFI for the FSDF is the installation of soil moisture probes in thebackfill to monitor and quantify lateral and vertical infiltration beneath the impoundment .The data will be integrated with the bedrock investigation and used to evaluate .a finalremedy for the FSDF.
The proposed interim measures will address the immediate threat to human health and/orthe environment which exists from exposure to the dioxin , PCB, and mercury contaminated soilsin the FSDF surface impoundment . The interim measures (IM) also remove the potential ofexposure to soils and sediments in the drainage channels below the FSDF . Each passing season,there is a very high probability that the contamination may become more widespread in theenvironment if the contaminated soils are allowed to remain in place . Samples collected to datehave shown PCBs above cleanup levels extend a distance of 1,000 feet below the impoundment .For this reason , DTSC has determined the most protective and logical course of action is toremove the contaminated soils as quickly as feasible, thereby mitigating the most immediate threat
HDMSP00028136
Fanner Sodium Disposal Facility December 1999Response to Comments Page9
to human health and/or the environment . The next phase of remediation consists of investigationof the vadose zone contaminants followed by evaluation of remedial options , which will proceedas part of the site-wide investigation . Once data collection and analysis is complete , DTSC willpropose a final remedial design .
Comment 2
The IM tasks described to support the project objectives are incomplete . Theymust include the following to provide satisfactory stabilization on an interim basis:. . .b) Provision of a back fill strategy (designed cap, liner, etc.) that precludes infiltration ofrainfall or run-on water. Contaminant migration, through the poorly investigated,un-remediated, unsaturated fractured bedrock which underlies the former FSDF andoverlies ground water should be prevented as part of this IMproject ; c) Provision ofadequate monitoring of the underlying fractured bedrock to assure that the backfilldesign precludes contaminant migration . . .
[21
Response
DTSC believes satisfacto ry stabilization will be provided on an interim basis by the sixmeasures outlined in Response to Comment 1 .
Comment 3
DOE/Rocketdyne must indicate the fractured and transmissive nature of thebedrock and that contaminantsfrom the FSDF have migratedfrom the impoundmentthrough to ground water .
[2 ]
Response
A 98-day pump test designed to evaluate the degree of hydraulic communication in thefractured bedrock was conducted beginning on June 28, 1995 and ending on October 4, 1995 .The test consisted of pumping three to five existing monitor wells, monitoring pumpage volumesand rate and water quality changes at the pumped wells, and monitoring water level declines atnumerous nearby monitoring wells . The calculated transmisswity and permeability data arepresented in a report prepared by Groundwater Resource Consultants, Inc ., titledPilot Groundwater Extraction Test at Former Sodium Disposal Facility, Area IV,
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Former Sodium Disposal Facility December 1999Response to Comments Page 10
Santa Susana Field Laboratory dated November 25, 1996 . Joints, fractures, and staining,exposed in the bedrock during excavation activities will be mapped in detail and photographed aspart of the Interim Measure . Lithologic logs as well as video logs showing fracture spacing andfracture apertures exist for all well borings in and around the FSDF, and will be used for reviewand integration into a three-dimensional interpolation of the subsurface geology . Boeing'sconsultant, Montgomery-Watson, is conducting detailed geologic mapping (on a scale of 1 :500)of lithologic and structural features at the SSFL (including the FSDF) . The geologic mapping andfracture analyses are part of the site-wide groundwater RFI investigation currently beingconducted by Boeing' s consultants , Montgomery-Watson and Groundwater ResourceConsultants . The groundwater RFI includes a comprehensive review of analytical well data, wellconstruction details, pump test data, tracer test data, and spacial configuration. Data will becompiled into a report which will be submitted for review in early 2000 . It is anticipated that theRFI report will be a basis for additional groundwater characterization at the SSFL .
Comment 4
The overburden and groundwater concentrations of VOCs cited in this summarysupport DTSC's longtime contention that the fractured bedrock probably still containscontamination and will remain a continuing threat to ground water even after the"limited overburden" is removed Therefore, one component of the IMstabilization that
will be required is a temporary cap to preclude infiltration into the fractured bedrockportion of the vadose zone and long term monitoring under the temporary cap to assurethat it isfunctioning. Once installed this temporary ca may also be evaluated later aspart of the final remedy as opposed to the proposed backfill (that does not minimizepermeability, etc .) which would not be acceptable . (emphasis added)
Response
The IM stabilization will include installation of low permeability (4 x 10' cmis) claybackfill material . The backfill will be installed to a maximum thickness of 12 feet, compacted to90%, and completed with a 10% surface grade as specified in the IM grading plan. Followinginstallation of backfill, tests will be performed to quantify in-situ backfill permeabili ty. In-situmoisture probes will be installed in the backfill to monitor performance . The performance of theclay backfill/vegetative cover design was compared, using a nume rical model, with performanceof other design options, including installation of an impermeable HDPE liner cover over the claybackfill . The clay backfill/vegetative cover design performed significantly better (i .e . resulted inapproximately 55% less leachate passing through the base) than the HDPE liner design. Theimproved performance of the clay backfWvegetative cover design is due to removal of latent soilmoisture by plant evapotranspiration, which cannot occur when the backfill is covered with animpermeable liner cover . The Infiltration Monitoring Workplan will assist in monitoring lateralinfiltration . Once approved, monitoring probes will be installed in the back ill . As noted in
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• Fanner Sodium Disposal Facility December 1999Response to Comments Page I i
Response to Comment 1 above, DTSC believes the low permeability backfll and other controlmeasures outlined earlier will provide interim stabilization until the Corrective Measures Studyhas been completed and a remedy is selected .
Comment 5
Contrary to the requirements established in this letter , DTSC now proposes to a llowRocketdyne to (1) move forward with an interim remedial measure without having characterizedcontamination in the bedrock beneath the FSDF ; (2) place permeable backfill in the remediatedareas that will allow the infiltration of water rather than requi ring an impermeable cap to preventfurther degradation of ground water; and (3) go forward with the interim remedial measurewithout monito ring the bedrock for the infiltration of water and migration of contaminants .
[2]
Response
Refer to Response to Comments 1 through 4 .
Comment 6
The administrative record clearly establishes that DTSC had initially required thatRocketdyne construct an impermeable cap over the remediated areas at the FSDF. The incredibleinconsistencies in what had been required and what is now proposed raise a menagerie ofquestions . How did DTSC decide to back down from its stated requirement for a RCRA-likecap? Who made this decision? Did Rocketdyne, Rockwell, or Boeing representatives meet withsenior DISC officials (meaning the former Director , the Deputy Director , or any other suchperson based at DTSC headquarters)? If so, who attended this meeting? Was there more thanone such meeting . When did it (or they) take place? What was discussed? Did a senior DTSCofficial (or group of officials ) based at DTSC headquarters in Sacramento concede that a capwould not be required? If so, who was involved in this decision? On what basis was the decisionmade not to require a cap at the FSDF? Was this a political decision directed by senior DTSCmanagement ? Please be honest . Remember, this information could be forced out of the agencyand agency representatives under litigation discove ry of agency records and depositions underpenalty of perjury . If senior DISC officials decided that a cap would not be required, how wasthis information conveyed to the DTSC project manager? What role did Rocketdyne have in thisdecision? Who represented Rocketdyne at the meeting(s)? What did they ask for? What werethey told and by whom?
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Fonmer Sodium Disposal Facility December 1999Response to Comments Page 1 2
Response
The proposed IMWP will require the FSDF impoundment be backfilled with a lowpermeability clay backfill , up to 12 feet thick . The performance of the clay backfill was compared,using a numerical model , with performance of other cap designs, including incorporation of animpermeable HDPE liner cover over the clay backfill . Even though IIQ water was allowed toinfiltrate through the HDPE liner, the numerical model simulation indicated the proposed claybackfill/vegetative cover design is more protective (allowing less than 55% of the leachate to passthrough the base) than the HDPE cover design . The improved performance is due to removal oflatent soil moisture by plant evapotranspiration . In DTSC's judgment, given currentunderstanding of site geology and available data , the proposed clay backfill cap is the moreprotective design and meets the objectives originally outlined in DTSC's October 10, 1997 letter(refer to comments 1 through 4) . Further study and evaluation will be conducted before a finalsite remedial design is proposed .
A meeting was held on May 18, 1998 , at the SSFL site to discuss the FSDF InterimMeasures Workplan . DTSC representatives , Boeing representatives , and DOE Oakland
i representatives were in attendance . A presentation was made by Boeing on the components ofthe proposed Interim Measures Workplan . The agreements reached and scheduled action itemsare outlined in a May 29 , 1998 letter from Boeing to Phil Chandler . A copy of this letter wasincluded in the Administrative Record which was available for review during the Public Commentperiod . Based on the agreements outlined in the letter , Boeing was to submit by June 5, 1998,soil permeability tests and infiltration calculations on native soils . This information was receivedby our agency on June 5, 1998 . A decision was made by the Branch Chief that low permeabilitybackfill would meet the requirements of an interim cover . Boeing would conduct permeabilitytests on the soil that will be used for the cover , perform infiltration calculations, and installmonitoring probes in the backfill to monitor infiltration . The need for a permanent engine c~ cu capdesign would be evaluated later as pa rt of the final remedy selection process . It was determinedthat immediate action on removal of the contaminated soil was necessary to minimize the spreadof contaminants. A delay in removing contaminated soils could result in continued migration ofcontaminants offsite and would pose a risk to human health and/or the environment .
Comment 7
It appears that DTSC made a solely political decision to not require a cap because in itsletter of December 11, 1996, to Rocketdyne, DTSC wrote :
• It remains the technical opinion of the Geological Support Unit (GSU) that anadequate cap must be designed with appropriate run-off and erosion control provisionsand that vadose zone monitoring for residual contaminants be performed through thefractured rock portion of the vadose zone as part of the f gJ remedy for the FSDF.
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• Former Sodium Disposal Facility December 1999Response to Comments Page 1 3
Simply removing the remaining contaminated unconsolidated materials and replacingthem with uncontaminated soil is insufficient . (emphasis added)
Note that, in this context, the "interim measure" is supposed to be as close to a "finalremedy" as possible . Thus, a cap should be required now, not just later.
[2]Response
The basis for the decision is outlined in Response to Comment 6 above, and in previousResponse to Comments . Note that the quote from the December 11, 1996, memorandum refersto the final remedy for the FSDF. All remedy options, including the need for an engineered cover,will be considered during the Corrective Measures Process and will be based on technical merit .DTSC believes it would be premature to design and implement a RCRA-like Cap prior tocompletion of characterization activities at the FSDF .
Backfill with low permeability native material is consistent with a final remedy, whetherthat remedy is an engineered cap, vapor extraction system, thermal treatment system, or otheralternative technology, or combination of technologies . DTSC believes that the control measuresoutlined in Response to Comment l will provide adequate interim stabilization and protection .
Comment 8
On page 4-22 of the Interim Measure Workplan, Rocketdyne clearly states that thecurrently preferred DTSC alternative of backfilling with "soil similar to native material" would"allow water flow at the surface, through the soil, and along the soil-bedrock bowi .L,ry . . . "(emphasis added) . Thus, the infiltration of water to bedrock and, it is safe to presume , throughthe bedrock to ground water, is openly acknowledged . Given that DTSC has admitted, andcommon sense dictates, that the bedrock contains contaminants capable of reaching ground water,how can DTSC claim that the proposed interim measure will not have a "potentially significant"impact upon the ground water?
[2]
Response
The native soils in the vicinity of the FSDF are classified as clay with a tested permeabilityof 1 x l0'' cm/s . Infiltration calculations for this soil type and permeability were reported byBoeing to DTSC in a letter dated June 5, 1998 . The tested permeability for the proposed borrowsoils is 4 x 10~ cm/s . Both permeabilities are in the range of clay used for RCRA landfill coverdesigns . RCRA style covers typically incorporate two feet of clay cover over a soil backfill . As
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•Former Sodium Disposal Facility Deoembcr 1999Response to Comments Page 14
outlined in the proposed IMWP, the FSDF will be bac kfllled with up to a 12-foot thick clay cover .The performance (i . e . quantity of leachate which will migrate through the base) of the p roposedIMWP backfill design was compared with the performance of other design options (includingapplication of an impermeable HDPE liner cover) by use of a numerical model. The modelsimulation indicated better performance of the clay back £Wvegetative cover design whencompared with the HDPE cover (approximately 7,000 ga liyr vs . 15,000 gal/yr) . In addition, thelow permeability backfill cover , as outlined in the IMWP , will be engineered with a 10% grade topromote rainwater runoff. A v-ditch will be constructed to divert run-on rainwater . Even thoughthe impoundment is currently tarped, water accumulates underneath the tarp (40,000 gallons waspumped from beneath the tarp du ring the 1998 -1999 winter) . The engineered design of the lowpermeability backfill, therefore , will be more protective of groundwater than exists with thecurrent tarp , and therefore the proposed interim measure will clearly have no significant impactupon the groundwater .
Comment 9
Let's be clear about this . DTSC proposes to allow for the removal of a tarp currently in. place over the FSDF that prohibits infiltration of water to bedrock (and, therefore, ground water)
and replace it with backfill that allows for the infiltration of water . This is a discretionary agencydecision reviewable under CEQA . This is also a decision that will have a potentially significantenvironmental impact upon ground water . Either DTSC should provide for more protectivemeasures (i .e ., a cap capable of prohibiting infiltration) or it should proceed with anEnvironmental Impact Report on the proposed agency action prior to allowing any furtherremedial action at the FSDF . At minimum, DTSC should at least formally consider therequirement of an impermeable cap as a fourth proposed alternative under CEQA. Without suchconsideration (of a requirement having earlier been formally adopted by DTSC and communicatedto Rocketdyne ), DISC will not have complied with the CEQA requirement to take a "hard look"at alternatives .
[2 ]
•
Response
The protectiveness of the proposed day backfill design has been discussed previously inResponse to Comments 1, 4, 6, and 8 . The proposed project is an interim measure . The goal ofthe interim measure is to remove the dioxin, PCB, and mercu ry contaminated soils from theimpoundment and the drainage channels, which will prevent offsite migration of contaminatedsoils further down into the drainage channels towards inhabited areas below the facility . DTSCbelieves the control measures outlined in Response to Comment 1 are protective of groundwater .
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• Forcer Sodium Disposal Facility December 1999Responseto Comments Page 15
CEQA does not require an analysis of alternatives in an initial study . Pursuant to CEQAGuidelines Section 15063," . . . the lead agency shall conduct an ini tial study to determine if theproject may have a significant effect on the environment ." (emphasis added) . The informationand analysis presented in the initial study indicates that implementation of the IMWP , with projectcontrols and mitigation measures , will not have a significant impact on the envi ronment.Additionally, DTSC believes the measures discussed in Response to Comment 1 are adequate tocontrol impacts to groundwater until a final remedy is selected . This is supported by informationin the administrative record . Refer to the Response to Comment 10 for additional discussion onthe adequacy of the backfill mate rial .
While the findings of the IMWP initial study did not lead to preparation of an EIR, itshould be noted that DTSC: intends to prep are an EIR for selection and implementation of thefinal remedy for the entire SSFL site .
Comment 1 0
We find it pa rticularly disturbing that DTSC has not tested the proposed backfill materialto identify how much water will infiltrate to the bedrock and to ground water . On page 11 of theInitial Study, DTSC states, "Boeing will provide the permeability data for the imported soil toDTSC." (emphasis added ) . Thus, DTSC has not yet received , collected, or reviewed any dataabout the permeability of the soil that Rocketdyne plans to use as backfill . DTSC, therefore, lacksthe specific information necessary to judge accurately the impact of this proposed agency action .Yet, DTSC states that there will be no potentially significant impact upon ground water . Howcan DTSC make reach such a conclusion without any data? Something has gone seriously awrywith DTSC' s decision-making process . DTSC should not, and the law does not allow DTSC to,make such unfounded assumptions when conside ring potentially significant environmentalimpacts .
(2)
Response
Permeability data on three native soil samples , along with infiltration modeling analysesusing the U. S . EPA's Hydrologic Evaluation of Landfill Performance (HELP) model wasprovided to DTSC on June 5, 1998 . These data are part of the administrative record and wereavailable for review during the Public Comment period. Geotechnical evaluation of soil samplesfrom the proposed onsite borrow area was conducted by Pacific Materials Laboratory onJune 24, 1999. Calculated hydraulic permeability for the borrow source, based on testing of aclayey-silt sample, was 4.23 x 10' cm/s. Typical engineered covers for encapsulation ofhazardous waste landfills are designed with a two-foot thick clay layer (1 x 10 '' cm/s) over a baselayer of soil (usually with permeability of 1 x 10cmis) . The clay "cap" is overlain by a syntheticliner and a vegetative layer. In the proposed IM, the impoundment will be backfilled with
HDMSP00028143
Former Sodium Disposal Facility December 1999Response to Comments Page 1 6
compacted native clayey silts and clays up to twelve feet thick , with permeabilities only slightlymore than would be prescribed for the two-foot thick RCRA-like Cap. The performance of theproposed clay backfill design was compared , using a numerical model , to alternative designoptions, including incorporation of a HDPE liner cover over the clay bac kfill . The claybackfil l/vegetative cover performed best in the model simulation , allowing appproximately 55%less leachate to pass through to the base than the clay cover /HDPE liner design (7,000 gal/yr vs15,000 gal/yr) . This occurred despite the fact that more than 700,000 gallons of water infiltratedinto the backfill , according to the model simulation . The model simulation allowed no infiltrationto occur through the HDPE liner cover . The improved performance of the clay backfiWvegetativecover design is due to plant evapotranspiration which makes a significant cont ribution to theremoval of latent moisture from the backfill soils . DTSC believes backfilling with native borrowmaterial , and other control measures outlined in Response to Comment 1 are adequate to controlimpacts to groundwater until a final remedy can be evaluated and selected .
Comment 1 1
In its letter of December 11, 1996, to Rocketdyne, DTSC wrote, "Since groundwater inthe immediate vicinity of the FSDF is contaminated and no alternative sources have beenidentified or postulated, such contamination must indeed have migrated through the fracturedrock portion of the vadose zone." DTSC admits contamination has moved through bedrock toground water in the past, however, it fails to even assess the possibility that this will happen againin the future and concludes, with no supporting data, that this will not pose a threat to theenvironment .
[2]
Response
Factors contributing to the mobilization of contaminants into groundwater beneath theFSDF (either by near surface infiltrating groundwater or infiltration through fractures in bedrock)are complicated and not well understood . The "RCRA Cap" remedy proposed by the commenterwould not , for instance , prevent lateral infiltration beneath the cover . Such a design mightactually "trap" laterally infiltrating moisture beneath the IIDPE liner cover (since litt le evaporationand no evapotranspiration could occur), thereby increasing leachate . The proposed IMWPdesign , that of backfilling with a low permeabili ty clay with vegetative cover will minimize lateraland vert ical infiltration, with the benefit of retarding and removing infiltrating moisture (bothlateral and ve rtical) by evapotranspiration . Preselection of a final remedy such as a "RCRA Cap"is inapprop riate until proper characterization has been completed and all remedial optionsevaluated based on their technical merit . DTSC believes it would be inadvisable to delay removalof contaminated soils until a characterization and evaluation of remedial options have beencompleted . Such an action would unnecessarily delay removal of contaminated soil, contribute t o
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Former Sodium Disposal Facility December 1999Response to Comments Page 17
•
spread of contamination in drainages , and increase risks to human hea lth and the environment .Additionally, DTSC believes that the low permeability clay backfill and control measures outlinedin Response to Comment 1 are adequate to control impact to groundwater until a final remedy isselected .
Comment 12
Why doesn 't DTSC require Rocketdyne to provide protective measures comparable tothose required in Title 22 of the California Code of Regulations , Section 66264 .228, for theclosure of hazardous waste landfills? Isn't it true that, ifRocketdyne had told DISC aboutdisposing of hazardous mate rials at the FSDF after the enactment of RCRA, the company wouldhave had to cleanup the facility under these regulations? Isn't it reasonable to insist that thecompany be bound by requirements at least as restrictive as those required for honest companiesthat tell DTSC that they are dumping, or have dumped, hazardous wastes on their property?
[2 ]
Response
The FSDF was identified as a Solid Waste Management Unit (SWMU), and not as aregulated unit subject to landfill requirements , in the U.S. EPA's RCRA Facility Assessment(RFA) for the SSFL . The lower impoundment was subsequently declared subject to Toxic PitsCleanup Act (TPCA) and treated as a SWMU by the Regional Water Quality Control Board(RWQCB) in 1991 . Whether the FSDF is regulated as a landfill under Title 22 or subject toCorrective Action will ultimately have no substantial impact on cleanup objectives . The selectionof a final remedy for the FSDF will be based on technical merit , and protection of human healthand the environment .
Comment 1 3
Will DTSC require geological mapping and photography of fracture zones and joints andan assessment of potential pathways to ground water throughout the entire FSDF or just theupper pond and western area? Will the mapping include the production of three -dimensionalsubsurface interpolations of the potential location of contaminants and pathways to groundwater?Why hasn't DISC required Rocketdyne to use geologic sonogram technology to map thefractured bedrock? How and where will the findings of the geological mapping be reported?
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• Fanner Sodium Disposal Facility December 1999Response to Comments Page 1 8
Response
As outlined in the IMWP, joints, fractures , and staining exposed in the bedrock duringexcavation activities will be mapped in detail and photographed . Lithologic as well as video logsshowing fracture spacing and fracture apertures exist for all well borings in and around the FSDF,and will be used for review and integration into a three dimensional interpolation of the subsurfacegeology. Boeing's consultant, Montgomery-Watson, is conducting detailed geologic mapping(on a scale of 1 :500) of lithologic and structural features at the SSFL (including the FSDF). Thegeologic mapping and fracture analyses is part of the site wide groundwater RFI investigationcurrently being conducted by Boeing 's consultants Montgomery-Watson and GroundwaterResource Consultants . The groundwater RFI includes a comprehensive review of analytical welldata, well construction details, pump test data, tracer test data, and spacial configuration . Datawill be compiled into a report which will be submitted for review in early 2000 . It is anticipatedthat the RFI report will be a basis for additional groundwater characterization at the SSFL.
Comment 14
S Similarly, the United States Department of Energy (DOE) has committed to reconsideringthe cleanup standards used in the first interim remedial measure undertaken to remove radioactivecontaminants in soil in 1992. DOE discussed the issue of site-wide radiological cleanup standardsat the last meeting of the Santa Susana Field Laboratory inter-Agency Work Group, which theDTSC project manager and many other representatives of DTSC attended . Appropriatemitigation measures such as an impermeable cap would, therefore, protect againstthe potentially adverse impact of having to remediate radioactive contaminants at concentrationsthat may be in excess of those that will be found to be acceptable to DOE .
[2]
Response
Comment noted .
Comment 1 5
Boeing has failed to develop satisfactory information about the fractured bedrockcomponent of the environmental sett ing beneath and adjacent to the FSDF. These fracturescontrol migration of fluids on the periphery, perhaps into the rock underneath the FSDF .Fractures certainly control migration of any percolated fluids---as well as vapor-phase HVOCs---released from the FSDF into the soil/sediment and from there into the rock. 3-dimensional (3-d)seismic techniques should have been utilized to allow determination of degree of potential impac t
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• Former Sodiwn Disposal Facility December 1999Response to Comments Page 1 9
of migrating fluids on the contaminants that will be left in place in the fractured rock by thisdiscretionary decision. These contaminants are part of the project and the proposed actions mayimpact them . (p. 8, par 5, IS)
Response
The objective of the IMWP is to immediately remove a source of contamination. It is nota final remedy. Evaluation of fracture patterns and lithologic and structural controls on fluidmigrations in fractured bedrock at the FSDF is ongoing as part of the RFI investigation ofgroundwater at the SSFL (Refer to Response to Comment 13). A three-month pump testdesigned to evaluate the degree of hydraulic connectivity of the fractured bedrock beneath theFSDF was conducted in 1995, and a report summarizing findings submitted in 1996 . Planned andongoing measures which will help stabilize potential migration of contaminants through thefractured bedrock at the FSDF were discussed in Response to Comment 1 .
Comment 16
Backfilling the excavation with soil similar to native soil is not sufficient to mitigate theimpact of removing the " liner" or cover that Boeing has maintained prevents infiltration . Goingfrom something represented as an impermeable cover to a permeable backfill can clearly impactcontaminant migration in the underlying fractured bedrock . DTSC has failed to assure thatinfiltration will not occur . It has also failed to cause Boeing to specifically include and describe aspart of this project, monitoring devices which could se rve as mitigation . These devices shouldnow be added to the mitigation measures . Note, monitoring needs to be done in the backfill andin the fractures adjacent to and underlying FSDF (p. 10, par 4, IS) .
[4]
•
Respons e
Permeability data on the native borrow soil were discussed in Response to Comment 10 .Advantages and improved performance of the clay backfill, compared with alternative designs,such as use of an HDPE liner cover, were also discussed in Response to Comments 10 and 11 .Control measures to stabilize potential migration of contaminants and minimize infiltration areoutlined in Response to Comment 1 . Planned and ongoing measures which will monitor potentialmigration of contaminants are also outlined in Response to Comment 1 .
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Former Sodium Disposal Facility December 1999Response to Comments Page 20
Comment 1 7
Boeing has disposed of waste (metallic mercury in the soil is indicative of this) into theimpoundment(s) . It does not even have to meet the most minimum of requirements that might belevied on a impoundment which has been permitted to receive waste . For example , one of therequirements of interest stands in stark contrast because of a statement made in the workplan .Title 22 CCR indicates that a surface impoundment should have a final cover designed andconstructed to "prevent" downward entry of water into the closed impoundment for at least 100years . Boeing ' s workplan decides against low permeability backfill in pa rt because on-sitematerial---with no permeability requirement---will "allow water flow at the surface , through thesoil, and along the soil-bedrock boundary to approach background (native) conditions ." Thisargument presented with un-evaluated contamination still likely to be resident in the fracturedrock beneath the FSDF . The contrast between a permitted impoundment 's requirements and theFSDF proposal is start ling (p. 11, par 4, IS) .
[4]
Response
The technical merits of the proposed IMWP are outlined in Response to Comments 1, 4 ,6, 10, and 11 .
Comment 1 8
The impacts of revegetation on infiltration need to be examined and assessed . Roots canclearly increase infiltration . Boeing is trading off infiltration and potential impact oncontamination in the underlying fractured rock against run-off and sediment migration from its"clean" backfill . The potential impact has been ignored here (p . 11, par 4, IS) .
[4]
•
Response
Evaportranspiration is an important element in minimizing infiltration and percolationthrough soil caps . The tradeoff is a beneficial one. Deeper root zones exert greater capillarysuction, increasing the evaporative zone to depths greater than soils with no vegetation . In theinfiltration modeling analyses for the FSDF conducted using the numerical model LEACHM,evapotranspiration was a significant factor in removing infiltrating moisture .
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Former Sodium Disposal Facility Decemba 1999Response to Comments Page 21
Comment 19
The monitoring of the vadose zone alluded to in the Initial Study needs to be included hereas a mitigation measure . Determination of the fracture pathways underlying FSDF also needs tobe included as a mitigation measure . All CEQA monitoring and reporting requirements shouldapply (p . 3, par 1, IS) .
[4]Response
The vadose zone monitoring discussed in the Initial Study is not a component of theIMWP . Similarly, investigation of fracture pathways will be addressed as pa rt of the ongoingRFI. The final design of the monitoring plan and selection of probe locations into the backfill willbe based in part on information obtained following excavation of soils and exposure of theunderlying bedrock . Once exposed, fractures and other structural features will be mapped indetail . The vadose zone monitoring is considered pa rt of the ongoing RFI . Information obtainedfrom the probes will contribute to the determination of the final remedy for groundwatercontamination at the site . Refer to Response to Comments 1, 3, 4, and 10 .
Comment 20
If the IM is intended to be "consistent" with the ultimate "closure" requirements, thenTitle 22 CCR has some ve ry clear "closure" and post-closure care requirements that should beincluded herein , e .g . cap the former impoundment to prevent infiltration of water into theunderlying fractures which may be contaminated . It is clear that contamination reached groundwater from the FSDF, this means that the intervening fractured bedrock vadose zone has a highprobability to also be contaminated . Moreover, it means that without the "liner" and having nocap or even a requirement for low permeability backfill, infiltration water could act to mobilizecontamination and continue to impact groundwater . Not only is this contrary to Porter Cologne'srequirements regarding waste discharge that threatens ground water , it doesn't meet the IM testfor stabilization , and such mobilization would be an un -mitigated impact (p. 1-1, par 4, IMWP) .
[4]
Response
Permeability and performance of the backfill material , and ongoing and planned measureswhich will stabilize potential migration of contaminants through the fractured bedrock and intogroundwater are discussed in Response to Comments 1, 4, 10, and 11 .
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Former Sodium Disposal Facility December 1999
Response to Comments Page 22
Comment 2 1
The statement that further remedial measures may be performed at FSDF---if required---isnot reassuring . No ecological ri sk assessment appears to have been done . No evaluation ofresidual contamination in bedrock has been performed . Is Boeing suggesting that this "non-cap"would be removed and replaced at some unknown future date? This is far too loose anarrangement (p . 1-1, par 6, IMWP) .
[4]Response
The proposed project is an interim measure. A post-interim cleanup ecological riskassessment will be conducted (see Response to Comments 39 and 51) . DTSC reiterates that thefocus of the interim measure is to remove the PCB, dioxin, and mercury contaminated soils fromthe impoundment and thereby eliminate an immediate health and environmental threat, andeliminate the continued offsite migration of PCB and dioxin contaminated soils from the FSDF .As required by DTSC, Boeing will evaluate residual contamination in bedrock as well as anoptimal remedial technology during the RFI and CMS phases for the project .
Comment 22
This (fracture patterns ) is a pretense . Only part of the fracture issue is dealt with . It needsto be admitted that Boeing has failed to obtain the type of fracture information that would beuseful in this IM. It is necessary to know where to place vadose monitoring devices---whichshould be part of the mitigation measures since a "liner" is being removed and replaced withpermeable backfill . Three-dimensional seismic work---performed following excavation andbackfill, should be part of the IM to optimize sensor placement and to evaluate the situation withlateral infiltration (p. 1-6, par 4, IMWP) .
[4]
Response
Evaluation of fracture patterns and lithologic and structural controls on fluid migrations infractured bedrock at the FSDF is ongoing as part of the larger site-wide RFI investigation ofgroundwater at the SSFL . The bedrock fractures will be mapped in detail following removal ofthe contaminated soils and prior to backfilling with clean fill . The Infiltration MonitoringWorkplan for the FSDF will be reviewed for adequacy and moisture probe locations selectedbased in part on location of bedrock fractures obse rved during mapping of the exposed bedrock.Three-dimensional seismic mapping is incapable of resolving the fracture apertures present inChatsworth formation bedrock at the FSDF . See Response to Comments 3, 13, and 15 .
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Fanner Sodium Disposal Facility December 1999Response to Comments Page 23
Comment 23
Contaminants have migrated into both zones across the site . This project needs to addresscontinued vadose zone migration that may be increased as a result of the project' s failure toassure provision of an impermeable or even low permeability cover. Thus ground water cannotbe simply passed off as being deferred to a corrective measures study at some future point in time(p. 1-6, par 5, IMWP) .
[4]
Response
The ongoing and planned measures which will control impacts to groundwater arediscussed in Response to Comments 1 and 10.
Comment 24
The groundwater pathway should specify fractured rock at FSDF (p . 2-5, par 8, IMWP) .
[4 ]
Response
The IMWP reads that, for the Groundwater Migration Pathway, chemicals of concernpresent in sediment and soils may dissolve in the water percolating "through the vadose zone" andmigrate vertically to groundwater and then to receptors . The vadose zone is defined as that zonebetween the ground surface and the zone of saturation (i .e . groundwater) and includes thefractured bedrock .
Comment 25
[Table 2-4] . The groundwater pathways avoid VOCs---these most likely exist in thefractured rock and need to be addressed now . The same is true of other COCs that might bemobilized (p : 2-5, par 10, IMWP) .
[4 ]
•
HDMSP00028151
•Former Sodium Disposal Facility December 1999Response to Comments Page 24
Response
Table 2-4 refers to the migration pathways for PCBs , dioxin, and mercury, present insurface soils at the FSDF . The purpose of this IM.WP is to remove the potential for offsitemigration of contaminants through surface water and sediment migration . Evaluation andremediation of VOCs in Chatsworth bedrock is being addressed as pa rt of the RFI . The controlmeasures outlined in Response to Comment 1 will stabilize VOC migration .
Comment 26
Stabilization at FSDF needs to be more ho listic, more is at stake than migration intosurface channels . The groundwater pathway may be impacted by this proposed project and needsto be addressed here as well . Deferral of all aspects of vadose impact is not acceptabl e(p. 2-6, par 1, IMWP) .
[4]
• Response
Refer to Response to Comments 1 and 10 .
Comment 27
Will the drainages below the FSDF be capped?[1 .e]
Response
All sediments in the drainage channels below the FSDF will be removed by handcrewsusing shovels and brooms. The drainage channels will not be capped .
HDMSP00028152
• Fanner Sodium Disposal Facility December 1999Response to Comments Page 25
CEQA INITIAL STUDY/ENVIRONMENTAL IMPACT REPORT
•
Comment 28
The Initial Study and work plan fail to provide sufficient information to judge theenvironmental impact of the proposed agency action on future discharges to ground water .DTSC omits any discussion of the relationship between water protection laws and regulations andthe long -term ground water impact of contaminants remaining in soil at levels identified as targetremediation goals . For example, if DISC has concluded that leaving 20 milligrams per kilogramof mercury in soil will not result in surface and ground water contamination in excess of statutorylimits and regulatory standards, then the process by which DTSC reached that conclusion shouldbe explained in the Initial Study . DTSC should include in the Initial Study a clear and detailedexplanation of the assumptions, theo ries, and rationale for determining future compliance not onlywith the risk assessment, but also with the Clean Water Act, the Porter-Cologne Water QualityControl Act, and other applicable statutes and regulations. Having failed to provide such adiscussion, the public does not have adequate information to provide meaningful comments andDTSC cannot make a fully informed decision . The Initial Study should be reasonably informativeas stand alone documents . It is not .
[2 ]
Response
The CEQA Initial Study applies only to the IMWP . Investigation of other OperatingUnits (OUs), including bedrock and groundwater , will be conducted as part of the RFI andsubsequent environmental and human health baseline ri sk assessments will be done . Thisinformation will be used in tt~e CMS to assist in choosing appropriate remedial action .
As is clearly indicated in the IMWP in the figures depicting mercury excavation limits(Figure 1-6, IMWP), all mercury contamination will be excavated to levels near or below thelaboratory detection limit . Following excavation, confirmation samples will be collected. Anynew data will be evaluated in the post-remediation ri sk assessment as part of the CMS and anycontamination resulting in unacceptable human health or environmental risks or hazards will beaddressed .
To address environmental risks, Boeing will prepare a post-interim measures ecologicalrisk assessment (ERA) for the FSDF ponds and channels . Methodology for the ERA is detailed inthe SRAM (see Response to Comment 39) . If the ERA concludes that risks to ecologicalreceptors are unacceptably high, further investigation and/or remediation will be required by
• DTSC.
HDMSP00028153
December 1999
•Response to Comments Page 26Former Sodium Disposal Facili ty
Comment 2 9
The Initial Study fails to assess the cumulative impact of the proposed agency ac tion inrelation to other projects and activities . DTSC should assess the cumulative impact of ongoingand future remedial measures at the site and activi ties being undertaken , or planned to beundertaken, in the immediate vicinity of the facili ty, including the development of adjacentproperty as part of the Ahmanson Ranch project .
[21
Response
Section 17 - Cumulative Effects (page 43) of the Initial Study provides an analysis of theIMWP impacts in relation to other projects . The Initial Study determined that the IMWP'sincremental contribution to cumulative impacts is not significant . The Initial Study alsoacknowledged that DTSC would comply with CEQA for any actions proposed as a result of theRFI . Potential impacts associated with the IMWP activities will be temporary . These activitieswill be completed well before commencement of the Ahmanson project . Therefore, DISC has
S determined that it would be more approp riate to consider the Ahmanson project when analyzingthe impacts of the final remedy .
Comment 30
In the Initial Study consideration of possible public health and safety impacts , DTSC doesnot fully and accurately describe the proposed agency action . The "potentially affected"environmental conditions include surface and ground water , plant life, animal life, public healthand safety , and cumulative effects. We ask that DTSC reconsider its proposed position that theseareas will not be "potentially affected" by this project . Without reasonable and adequatemitigation measures requiring protection against these potentially significant environmentalimpacts, DTSC will not be in compliance with the statuto ry requirements of CEQA .
[21
•
Response
Refer to Response to Comments 1, 3, 4, and 9 . It is DTSC' s position that any potentialimpacts to these areas will be reduced to a less than significant level through project controlsand/or mitigation measures .
HDMSP00028154
•
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Fanner Sodium Disposal Facility Dooember 1999Response to Comments Page 27
Comment 31
The "no impact" designation needs to be changed to "potentially significant unlessmitigated " (p.12, par 1 , IS; Commenter is referring to Earth Section of the IS) .
[4]
Response
Based on the existing discussion in the initial study , the "no impact" determination isappropriate . The initial study does not identify any potential impacts to geology or soils thatcannot be controlled by conditions established in the IMWP . These conditions are consideredpart of the project rather than mitigation measures . The commenter has not identified any newissues which may be a source of significant effects . Therefore, the "potentially significant unlessmitigated " determination is not appropriate .
Comment 32
This particular project is part of many projects, such as Happy Valley, that are or will begoing on at SSFL . The "short duration" should be considered in context of the cumulative impacteffect of the various other projects (p. 15, par 5, IS) .
[4]
Response
The Initial Study found that project controls and mitigation measures will limit anyimpacts.associated with this project and stated that any actions resulting from the ongoing RHwould be subject to CEQA . Pursuant to Section 15061(bx3) of the CEQA Guidelines, DTSChas determined that there is no possibility that the investigative activities occurring in HappyValley may have a significant effect on the environment and therefore they are not subject toCEQA. Impacts associated with detonation of ordnance discovered in Happy Valley and theIMWP are different and will not result in similar, and therefore cumulative, impacts . TheHappy Valley detonation of 64 ordnance items was completed on September 23, 1999 .
Comment 3 3
A mitigated negative declaration finding was made (p. 1-2, par 8, IMWP) .
[4]
HDMSP00028155
Former Sodium Disposal Facility llooanba 1999Response to Comments Page 2 8
Response
The text will be corrected .
•
•
Comment 34
The cleanup goals do not appear to take into account the reproductive and developmentalhealth requirements in Proposition 65 . DTSC should clarify this issue in the Initial Study
[3 ]
Response
The IM is not a final remedy . A final risk assessment will be calculated as part of theCMS during which appropriate reproductive and developmental health requirements will be takeninto account .
Comment 35
The Initial Study should include an assessment of the endangered species issues raised byMary Blevins of EPA in her May 23, 1997, memorandum to Tom Kelly .
[3]
Response
A biological assessment report prepared by Ogden Environmental , Inc. for Rocketdyne("Biological Conditions Report , Santa Susana Field Laboratory, Ventura County" datedAp ri l 1998 ) was consulted in the preparation of the FSDF IMWP . The Biological ConditionsReport presents an inventory of biota observed or potentially present at the SSFL (including theFSDF pond and channels), and includes an inventory of species of special concern (e.g ., state orfederally listed threatened or endangered ) that have been observed or are potentially present at thesite . The Biological Conditions Report was utilized in the investigation rather than thememorandum prepared by Mary Blevins ofU .S. EPA because (1) similar species of specialconcern are identified in both documents , and (2) presence of species of special concern and ofsensitive plant and animal habitats are field ve rified in the Biological Conditions Report .
HDMSP00028156
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Former Sodium Disposal Facility Dccanber 1999Response to Comments Page 29
Comment 36
Will the DTSC consider doing an EIR for the entire SSFL instead of a series of InitialStudies?
[ii, 1 .m, 6]
Response
DTSC, as the lead agency , has determined that, for many of the future remedial actionsand decisions, an EW is necessary to address the overall cleanup of the site .
HDMSP00028157
• Former Sodium Disposal Facility December 1999Response to Comments Page 30
CLEANUP AND ABATEMENT ORDER
•
Comment 37
We have enclosed a review of regulatory, geological, and hydrogeological issues related tothe Rocketdyne facility by registered geologist and certified hydrogeologistFranklin J. Goldman. Mr. Goldman concludes that "there has been a concerted effort to avoidcleanup of solvents discharged to groundwater as well as identifying the pathway for continuingdischarges to the groundwater (at the facility) ." He raises a wide variety of issues, many of whichare directly applicable to the proposed interim remedial measure . Among the more interestingpoints made by Mr . Goldman is the assertion that Rocketdyne has never complied with theCleanup and Abatement Order for the FSDF issued by the Los Angeles Regional Water QualityControl Board (RWQCB) in 1991. As lead agency for this site, why hasn't DISC required theenforcement of this order? Has DTSC informed or consulted with the RWQCB about theasserted ongoing violation of the Cleanup and Abatement Order? We incorporat eMr. Goldman's analysis into our comments by reference and attachment and ask that DTSCreview and respond to the issues raised by Mr. Goldman .
Response
DISC has reviewed Mr. Goldman's comments concerning the Cleanup andAbatement Order (CAO) 91-061 for the FSDF issued by the Los Angeles Regional Water QualityControl Board (RWQCB) on April 30, 1991 . Mr. Goldman asserts that the lower impoundment"was not cleaned up and closed in the time required and the groundwater monito ring required wasleft in limbo ." The CAO required the following:
1 . Submission of a closure plan for the lower impoundment by August 1, 1991 .2. Permanent closure of the lower pond by removal of all contaminated soil and debris and
verification sampling by December 31, 1992 .3 . Submission of quarterly reports of progress until closure activities are completed for the
lower pond .4. Submission of a plan for incorporating the groundwater contamination from the surface
impoundment into the site-wide cleanup of groundwater by December 31, 1992 .
DTSC review of the records, including a RWQCB closure letter for the surfaceimpoundment, suggest that all elements of the CAO have been met . A closure plan was submittedon July 31, 1991, and approved by the RWQCB in February 1992 . Excavation activities began inearly May 1992 and were completed in December 1992 . A plan for incorporating thegroundwater contamination into the site-wide cleanup (titled "B/886 Former Sodium DisposalLower Pond Interim Post-Closure Plan") was submitted to the RWQCB on December 22, 1992 .In .a letter to Rockwell Inte rnational dated December 29, 1992, the RWQCB reviewed theDecember 22, 1992, Post-Closure Plan and all data submittals and concluded that "all debris and
HDMSP00028158
•
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Former Sodium Disposal Facility December 1999Response to Comments Page 31
soil contamination have been removed from the Lower Pond in accordance with this Board'sCleanup and Abatement Order (CAO) No . 91-061 , issued on April 30 , 1991 , and this TPCAsurface impoundment is considered closed in accordance with the TPCA requirements ofclosure ." Evaluation of the groundwater contamination at the FSDF has been incorporated intothe site-wide groundwater investigation as stipulated in the CAO . Contrary to Mr. Goldman'sstatement that "the groundwater monitoring required was also left in limbo ," there are currently14 groundwater monitoring wells and 2 interim groundwater remediation systems operating at theFSDF impoundment . A three-month p ilot groundwater extraction test was conducted on fivewells at the FSDF in 1995 . The resulting pump test data were used to evaluate hydraulicproperties of the aquifer . Long term impacts of operating the extraction wellfield were evaluatedusing an analytical groundwater model . Approximately 40,000 gallons of groundwater waspumped and treated in 1998 . Status reports for the Interim Groundwater Renediation Systems atthe FSDF Areas are prepared monthly and available for review . The next phase of remediationconsists of investigation of contaminants in the bedrock followed by evaluation of remedialoptions , which will proceed as part of the site-wide investigation .
HDMSP00028159
• Former Sodium Disposal Facility Dcccmba 1999Response to Comments Page 32
MERCURY CLEANUP GOALS
Comment 38
Soil with mercury at or above 20 mg/kg is being disposed as a hazardous waste . Pleaseexplain the issue of a cleanup goal for mercury not being determined (p . 2, par 2, IS) .
[4 ]
Response
All of the mercury contamination in the FSDF is co-located with PCB and dioxincontaminated soils . All known mercury contamination will be excavated along with the PCB anddioxin contaminated soils. Based on characterization data , remaining mercury concentrations insoils following completion of the IMWP will range from non-detect (<0.10 mg/kg) to levels justabove the laboratory detection limit - levels which are expected to be well below health basedcleanup goal to be evaluated in the post remediation risk assessment . Following excavation ofsoils, confirmation samples will be collected from the bo ttom and all sidewalls . Any new data forremaining soils will be evaluated in the post-remediation risk assessment as pa rt of the CMS andany contamination resulting in unacceptable human health or environmental risks or hazards willbe addressed .
Comment 39
Isn't it true that the 20 mg/kg cleanup goal for mercury has not been based on an analysisof the risk to human health and ecological receptors? In its May 1998 comments on the InterimMeasures Work Plan (IMWP) attached to its June 11, 1998 letter to Rocketdyne, DTSC wrote :
The IMWP proposes to excavate soil only until mercury concentrations do notexceed 20 mg/kg . This level was developed only to classify waste as hazardous fordisposal at landfills and is not a risk-based number for human or ecological receptors.The proposed revegetation with native species will likely recreate suitable habitat forwildlife at the FSDF ponds and western area where levels of mercu ry below 20 mg/kg willremain . An assessment of the ecological receptors needs to include the impact frommercury concentrations less than 20 mg/kg. (emphasis added)
•We would like to know why DTSC has not enforced this requirement . Why hasn't there
been any analysis of the impact upon ecological receptors ?
[2]
HDMSP00028160
Former Sodium Disposal Facility December 1999Response to Comments Page 33
Response
Please refer to Response to Comment 38 regarding 20 mg/kg as a cleanup goal formercury contamination at the FSDF . Following ecological risk assessment (ERA) methodologydetailed in the SRAM, Boeing will prepare an ERA for the FSDF ponds and channels. Theevaluation will include mercury and other contaminants of potential ecological concern . Theevaluation will address the FSDF pond and stream channel areas as they exist followingpost-interim cleanup measures . If the ERA concludes that risks to ecological receptors areunacceptably high (e .g., mercury concentrations in soil cause exceedences of ecological toxicitythresholds), further investigation or remediation will be required by the DTSC .
Comment 40
With regard to mercury, the problem is worse . First, as described previously, theproposed cleanup levels are not based on health-based or environmental impact calculations .Second, we find no evidence that DTSC or Rocketdyne considered the results of the 1997 EPAstudy of mercury toxicity ("Mercury Study Report to Congress") . EPA concluded that mercuryposes a much greater threat than assumed in current risk-based calculations . To be confidentabout the level of protection afforded by the proposed interim measure, DISC should require thatRocketdyne base the cleanup goal for mercury on the more restrictive risk estimates identified byEPA. I have enclosed a printout of a web page describing the EPA study and providing links tocopies of the various study volumes . We would like to know whether DTSC considered the EPAfindings on mercury toxicity and whether DTSC will establish a more protective cleanup goalbased on these findings .
[2]
Response
All of the mercury contamination in the FSDF is co-located with PCB and dioxincontaminated soils . All known mercury contamination will be excavated along with the PCB anddioxin contaminated soils. Based on characterization data, remaining mercury concentrations insoils will range from non-detect ((0 .10 mg/kg) to levels just above the laboratory detectionlimit - levels which are expected to be well below health based cleanup goal to be evaluated in thepost remediation risk assessment . Following excavation of soils, confirmation samples will becollected from the bottom and all sidewalls . Any new data will be evaluated in the postremediation risk assessment as part of the CMS and any contamination resulting in unacceptablehuman health or environmental risks or hazards will be addressed .
•
HDMSP00028161
• Former Sodium Disposal Facili ty December 1999Response to Comments Page 34
Comment 41
The proposed decision to allow anything less than 20mg /kg of mercury to remain at theFSDF should be considered a potentially significant environmental impact, especially since itappears that no assessment has been undertaken to estimate the impact of this level ofcontamination upon potential ecological receptors .
[2l
Response
The decision was nQ1 to allow mercury concentrations in soil above background levels .Potential risks to ecological receptors will be addressed as described in the Response toComment 39 . The elevated mercury concentrations in the soil are co-located with the PCB anddioxin contamination . Residual mercury levels in the sidewalls of the excavation will range fromnon-detect to levels just above the laboratory repo rting limit based on the characteriza tion data -levels which are expected to be well below health based cleanup goals . Following excavation ofsoils, confirmation samples will be collected from the bottom and al l sidewalls . Any new data willbe evaluated in the post-remediation risk assessment as pa rt of the CMS and any contaminationresulting in unacceptable human health or environmental risks or hazards will be addressed .
Comment 42
It is puzzling to state in the same paragraph that no Cleanup Goal was established formercury but that it might be present in sufficient concentration to produce a hazardous disposalclassification . A further explanation would seem to be in order as to why something might behazardous but not need to be cleaned to some goal (p . 2-7, par 3, IMWP) .
[4]
Response
A cleanup goal is not necessary, since mercury contamination will be excavated andconfirmation samples will be collected . Residual levels will range from non-detect to levels justabove the laboratory reporting limit - levels expected to be well below health based cleanup goals .Any new data will be evaluated in the post remediation risk assessment as part of the CMS andany contamination resulting in unacceptable human health or environmental risks or hazards willbe addressed/remediated .
HDMSP00028162
Former Sodium Disposal Facility Dooember 1999Response to Comments Page 35
HUMAN HEALTH RISK ASSESS MENT
Comment 43
We did not find any evidence that DTSC or Rocketdyne considered current and emerginginformation about the toxicity of dioxin in establishing the so-called "health-based" cleanup goalfor the FSDF. We have enclosed printouts of web pages on this subje ct found through the website of the United States Environmental Protection Agency (EPA). These documents suggest thatthe cleanup goals for, dioxin may not be protective of human health and the environment . HasDTSC considered the EPA reassessment of the toxicity of dioxin? Will DTSC consider revisingits cleanup goals based on the results of the upcoming international symposium on dioxin to beheld in Venice, Italy, on September 12-17, 1999 ?
[2]
Response
The cleanup level chosen by DTSC is consistent with current national standards and themethodology for determining appropriate cleanup goals uses EPA approved parameters and isconsistent with state regulations . The United States Agency for Toxic Substances and DiseaseRegistry (ATSDR) has established an action level for polychlorinated dibenzo (p)dioxin anddibenzofurans of one part-per-billion (ppb) total TEQ in residential soils . This ATSDR actionlevel has been endorsed by U.S. EPA, DTSC, and the Cal -EPA Office of Environmental HealthHazard Assessment as appropriate for screening residential soil samples when they are analyzedfor dioxin, along with the conclusion that soils below the I ppb action level require no action tobe taken for purposes of public health protection . Toxicity criteria, i.e., RfDs, are based onadequate studies reviewed by the Standards and Criteria Workgroup of Cal EPA .DTSC will consider all relevant , published studies and has used currently approved toxicitystandards and data which have undergone scientific review and have been found to be acceptableand recommended by U.S . Environmental Protection Agency and ATSDR .
Comment 44
Why would DTSC allow dioxin levels at greater concentration than site backgroundmeasurements are reputed to be? What is the specific justification for a "regional" level? What isa "regional " level of inorganic constituents? Regional is used but this also seems to translate toCalifornia-wide. Please explain how California-wide relates to "regional similarities incomposition ." Why not simply leave it requi ring a level protective of human health and theenvironment ---which it should be noted includes ground water and burrowing animal s(p. 10, par 4, IS).
[4]
HDMSP00028163
•
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Former Sodium Disposal Facility December 1999Response to Comments Page 36
Response
The risk associated with exposure to dioxin compounds will be acceptable based oncomparisons with site specific, unimpacted background soil, which is geologically similar to sitesoil . Cleanup to levels which are below background is impractical . Risks to human andenvironmental health will be acceptable or below those associated with background . AnSSFL-specific background data set is being evaluated.
Comment 45
Boeing indicates in the workplan that dioxin is at a high at the Area IV bounda ry anddecreases down the channel . It is possible that low -dioxin sediments will be replaced withhigher-dioxin "clean" fill materials? Has this impact been evaluated?
[4 1
Response
Exposure to fill material, at < 10 parts per trillion (ppt), will result in risks and hazardswhich are less than background levels and less than the risk-based cleanup level of 13 ppt(p . 11, par 5, IS) .
Comment 4 6
This implies the anticipation is reality and since there will be no problem from theseconstituents no analyses are necessary . This is fascinating logic . If nothing else one mightconsider air samples being analyzed for these constituents during the excavation process(p. 1-2, par 1 , IMWP) .
[4]
Response
All chemicals detected in at least one soil or sediment sample , were included for evaluationas a Chemical of Potential Concern (COPC) . Air monitoring for mercury vapors , VOCs, and dustare described in the Worker Health and Safety Plan (Appendix B of the 1MWP) .
HDMSP00028164
Former Sodium Disposal Facility December 1999Response to Comments Page 37
Comment 4 7
Interesting that the dioxin highs were at the Area IV bounda ry, just as the PCBs, but thatsuch dioxin occurrence is interpreted as background (p. 2-2, par 8, IMWP) .
[4]
Response
If levels of dioxin at the Area IV boundary are below background and are subsequentlyremoved and replaced with clean (< 10 ppt) fill soil, then it is not relevant whether the initiallevels at the boundary are greater than other samples collected from the drainage channels whichare also below background .
Comment 48
Does the post remediation risk of 8 x 10include removal of dioxin and othercontaminants , as well as PCB?
[la, 1 .8]
Response
The Post-remedial risk of 8 x l 0'' includes removal of dioxin, mercury, and PCBs .
Comment 4 9
How does this post- remediation risk compare to exposure risks for non-contaminatedareas such as a neighborhood park?
[1•g ]
•
Response
This post -remedial risk estimation is based on contaminant concentrations which are at orbelow background concentrations . Estimating the risks at a specific neighborhood park wouldrequire sampling of exposure media and characterization of total exposure .
HDMSP00028165
Fanner Sodium Disposal Facility December 1999Response to Comments Page 38
Comment 50
Is the post-remediation risk of 8 x 10'' based on outdated assumptions and standards?
Respons e
Assumptions used in this risk assessment are based on recent , acceptable data and areconsidered current. The estimated exposures are derived from parameters published by theU. S. EPA in Exposure Factors Handbook, U. S. Environmental Protection Agency, inRisk Assessment Guidelines for Superfund Sites , U.S. Environmental Protection Agency, 1991,and the Department of Toxic Substances Control's Preliminary Endangerment AssessmentMethodology, 1994. The Cancer Slope Factors are published by the Standards and Criteria WorkGroup of Cal EPA, 1996 (June 3 update) .
•
•
HDMSP00028166
Former Sodium Disposal Facility December 1999Responseto Comments Page 39
ECOLOGIC RISK ASSESSMENT
Comment 5 1
With no ecological risk assessment , how can it be reasonably stated that this project willhave no impact on animal life . It needs to be considered that burrowing animals such as squirrels,gophers, etc., could be affected by residuals (as well as other animals that prey upon them)---andthe CEQA project includes the decision as to how much contamination to leave behind . At aminimum this should be a maybe since the work doesn 't appear to have been done on eco- risk(p. 22, par 9, IS) .
[4]
Response
As detailed in the draft Ecological Scoping Assessment Report (appended to theJune 19, 1998 version of the SRAM),. the FSDF pond and stream channel areas are characterizedas rock outcrop, nonnative grassland, ruderal, coast live oak woodland , and chaparral habitats .Impacts of soil removal on rare , threatened, or endangered (sensitive) animal species and theirhabitats were evaluated in the Initial Study . The Initial Study concluded that there would be nodisplacement of sensitive animal species nor destruction of sensitive animal species habitat . Thisconclusion is based on the following information : ( 1) Field observations (Biological ConditionsReport prepared by Ogden Environmental for Rocketdyne and dated April 1998), revealed noendangered animal species or their habitats in proposed soil removal areas within the FSDF pondand stream channels. (2) Review of the California Department of Fish and Game NaturalDiversity Database indicated no historical sightings of sensitive animal species in the proposed soilremoval areas .
Under no circumstances should the sensitive species habitat evaluation described in theFSDF workplan be considered as the final ecological assessment of the FSDF. The FSDFremoval action is an interim cleanup measure designed to alleviate immediate threats to humanhealth and the environment . Following ecological risk assessment (ERA) methodology detailed inthe SRAM, Boeing must prepare a post-remedial ERA for the FSDF ponds and channels (seeResponse to Comment 39) . The evaluation will address the FSDF pond and stream channel areasas they exist following post-interim cleanup measures . Receotor species in the assessment willinclude plants , invertebrates, insectivorous birds , burrowing mammals , and predatory birds andmammals . If the ERA concludes that risks to ecological receptors remain unacceptably high,further investigation or remediation will be required by DTSC .
•
HDMSP00028167
Former Sodium Disposal Facility Docember 1999Response to Comments Page 40
Comment 52
Where (sic) isn't ecological risk specified here as a missing risk component (p . 1-2, par 5,IMWP) .
[4]
Response
An ecological risk assessment is planned as pa rt of the Corrective Action for the SSFL.(see Response to Comments 39 and 51) .
•
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HDMSP00028168
•Former Sodium Disposal Facility December 1999Response to Comments Page 41
VERIFICATION SAMPLING
•
Comment 53
If perchlorate is being included in the project only because it is reported from groundwater beneath the FSDF , then by that logic halogenated volatile organics need to be included aswell (p . 2 , par 2, IS) .
[ 4 1
Respons e
No significant volatile organic compounds (VOCs) were found in 76 soil and sedimentsamples collected during the 1995 FSDF Characterization . It is likely VOCs that were present insoils at the FSDF have volatilized since excavation activities conducted in 1992. Problems withanalyzing VOCs from bedrock chip samples are discussed in Response to Comment 57 .Perchlorate was included as an analyte in the verification samples because it has not been analyzedduring previous characterization efforts .
Comment 54
The sampling grid size should be specified here in order to a llow evaluation of its use asthe basis for verification sampling , etc . (p . 2-10, par 6, IMWP) .
[4]
Response
The surveyed sampling grid size will be 50-feet by 50-feet and will be referenced to thesame survey marker referenced during the 1995 characterization study .
Comment 55
Verification samples should be obtained at all significant lithologic contacts, visuallyobservable staining and/or mercury presence---sniffer anomalies , and significant organic vaporanalyzer (OVA) readings . At a minimum, representative samples must be obtained every2.5 vertical feet from ground surface and at ten-foot lineal separation on the excavation
• sidewalls---Table 4-2 on p. 4.9 needs to be modified . Boeing did not take a large number ofcharacterization samples, therefore ve rification needs to be more detailed (p. 4-8, par 5, IMWP) .
[41
HDMSP00028169
• Former Sodium Disposal Facili ty December 1999Response to Comments page 42
Response
As outlined in Section 4 .1 .3 .3 . 2 (Sampling and Analyses Procedures - ExcavationVerification) sidewall verification samples will be collected around the initial perimeter of theexcavation at approximate increments of one sample each 25 linear feet ". . .or at locations of stainsor observable signs of contamination . . . ." DTSC personnel will be present during excavationactivities to ensure verification samples are collected from suspe ct areas . The 25 lineal feet an d5 feet vert ical separation combined with biased sampling will provide adequate indica tion ofcontamination on the cut face . For bedrock verification samples, the text will be corrected toinclude biased sampling at locations of stains and obse rvable signs of contamination, in addition torandomly located samples in each sample grid .
Comment 56
The selection of bedrock samples , shown in Table 4-2 on p . 4-9, needs to be revised from"random." Samples should be selected from bedrock, in part based upon overlying soil/sedimentconcentrations, observable chemical effects on the bedrock (if any ), fracture control, etc. In otherwords a more detailed strategy needs to be proposed (p. 4-8, par 5, IMWP) .
[4]
Response
As outlined in Section 4 .1 .3 .3 .2 of the workplan, random bedrock samples will becollected at grid locations and will coincide with the previous sample locations established in theFSDF Characterization Report . The random samples , therefore, will be collected at ;i prssampling locations , not just locations with elevated concentrations. Biased samples will becollected at visually observable staining .
Comment 57
Since HVOCs are found in ground water ---having putatively traveled from theimpoundment(s) through fractured rock , it seems only reasonable that the which ever portion ofthe impoundment(s) that served as source(s) should be determined and evaluated before thebackfill is placed . This would aid future investigation /remediation . Therefore , HVOCs need to beanalyzed from the chip samples and appropriate sampling strategies discussed in the workplan .
The random bedrock sampling approach is simply not appropriate(p. 4-12, par 5 , r wP) .
[4]
HDMSP00028170
• Fonner Sodium Disposal Facility December 1999Response to Continents Page 43
Response
Analyzing chipped bedrock samples for Volatile Organic Compounds (VOCs) would mostcertainly result in non-detect results due to the volatile nature of the analytes . Studies have shownsignificant loss of VOCs from soil samples within the first few hours ofcollection due to theirvolatility . VOCs in bedrock not immediately volatilized during excavation of overlying soil wouldlikely be lost following exposure to the atmosphere and daytime temperature . Those VOCsremaining in the bedrock that had not volatilized following exposure to the atmosphere, wouldmost certainly be lost during the process of collecting the chip samples with a hammer. Followingcollection, there would be no way to containerize the chip samples in a "no headspace" container .The data would have little meaning .
Comment 58
Will sampling be conducted in the drainage channels below the FSDF to ensurecontamination has not migrated offsite during prior rainy seasons into the residential areas?
Response
Sampling has been conducted in the drainage channels a distance of 2,000 feet below theFSDF impoundments. PCBs above the health based level were found in the drainage below theFSDF, a distance of 1,000 feet . Following removal of all sediments from the drainages ,verification samples will be collected. The verification sampling data will be evaluated in the postremediation risk assessmen t
Comment 59
Which laboratories conducted the analyses for soil samples collected at the FSDF ?
Response
Field studies at the FSDF were conducted from 1980 through 1995 . Laboratory analyticalreports and chain-of-custody forms for all samples collected as part of the investigation at theFSDF may be found in the repositories or the DTSC Glendale file room .
HDMSP00028171
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Former Sodium Disposal Facility Docember 1999Response to Comments page 44
Comment 60
Who will be collecting the confirmation samples from the FSDF following excavation ofthe contaminated soil?
Response
Confirmation samples will be collected by a field geologist employed by IT Corporation .DISC will be present to observe and ensure proper field sampling protocol is observed duringexcavation and sampling activities . Independent confirmation samples will be collected by DTSCat locations deemed approp riate .
HDMSP00028172
• Former Sodium Disposal Facility December 1999Response to Comments Page 45
WASTE CATEGORIZATION
Comment 61
The "bin characterization" protocol would seem to be an excellent means to average downhigh contaminant concentrations . At least one sample per bucket needs to be obtained . If one ofthe samples from a bucket is above the hazardous waste level, the bin it was placed in should bedesignated hazardous. Samples from the buckets should be discretely analyzed, since compositingallows for dilution of a "hot" bucket (p. 4-12, par 6, IMWP) .
[4 ]
Response
For manifesting and disposal purposes at Kett leman Hills Landfill, the bin characterizationprotocol is more than adequate to categorize hazardous waste (i .e. so ils with mercuryconcentrations averaging greater than 20 mg/kg) and non-hazardous waste (i .e . soils with mercuryconcentrations below 20 mg/kg) . Approximately one sample will be collected from eachexcavator bucket of soil (one bucket holds approximately one cubic yard ) before it is loadeddirectly into a roll-off bin. Each bin holds 15 cubic yards of soil , so 12 to 15 samples will becollected for each bin . The laboratory will compost three samples into one composite, resulting inapproximately five composite samples per bin . It is estimated that 22 bins will be necessa ry toremove the mercury impacted soils. If any one of the 5 composite samples from a bin exceeds theTTLC, the entire 15 cubic yards of soil will be categorized and shipped as hazardous waste .Using this protocol, it is far more likely that non-hazardous soils will be unnecessarily categorizedas hazardous and shipped accordingly than vice versa . For waste profiling, it's generally assumedthat the analytical data represents an averaging of concentrations. Otherwise, one could arguethat one discrete soil sample per bucket relies on an erroneous assumption that the mercu rycontamination is dispersed uniformly , and so additional profiling samples are needed to ensure a"hot" load is not missed . Taking this view to the extreme would necessitate that the soils beprofiled shovel full by shovel full .
Comment 62
Soluble mercury needs to be analyzed in samples less than 20 mg/kg . The apparentpresumption that solubility will always be low at FSDF needs to be tested(p. 4-12, par 6, IMWP) .
HDMSP00028173
Former Sodium Disposal Facility Dcoanber 1999Response to Comments Page 46
Response
The TCLP and STLC procedures are for waste manifesting purposes . Using the extensivetotal and soluble mercury concentrations obtained during excavation of the 10,000 cubic yards in1992, together with STLC and TCLP data from the first 7 bins of excavated soil, should provide areasonably accurate ratio of solubility for disposal purposes .
Comment 63
Mercury hazardous waste determination TTLGTCLP ratioing needs to be re-examined .Boeing has provided no technical basis for its proposed use ofa "site-specific minimum totalmercury" (p . 4-4, par 1, IMWP) .
[4]
Response
Refer to Response to Comment 62 .
Comment 64
Waste characterization should not be suspended because mixed down samples around ahigher mercury area are determined to be non-hazardous . The characterization study was .insufficiently detailed to support this (p. 4-12, par 6, IMWP) .
[4]
Response
As discussed in Section 4 .1 .3 .1 .3 of the IMWP (p. 4-6), waste profiling (for disposalpurposes) will continue for the next 225 cubic yards of soil, using the same profiling proceduresused for the first 325 cubic yards of soil . The process will occur iteratively until the mercuryTTLC is below 20 mg/kg .
•
HDMSP00028174
•Former Sodium Disposal Facility December 1999Response to Comments Page 47
BORROW SOURCE AND GRADING PERMIT
Comment 65
This section reads as if the grading permit (for backfuing) was already granted. Is thegrading permit issued? If not, why not? CEQA analysis would seem to require more specificity(p. 11, par 2, IS) .
[4]
Response
A Conditional Use Permit (CUP-248 ) (i .e . grading permit) for excavation, backfilling andgrading of the FSDF impoundments has been granted by Ventura County. CUP conditions areoutlined in Section l ("Earth") of the Initial Study . The CUP is being adjusted to allow for theuse of an on-site borrow site . Approval of the amended CUP by Ventura County is pendingrevision to the stormwater prevention plan for erosion control at the borrow site. Approval forthe amended CUP is expected to be granted in early 2000 . The amended CUP will stipulateconditions for erosion control, slope and final grading, and reclamation following cessation ofgrading in the borrow area each season . Approval of use of an on-site borrow area is contingentupon approval of the CUP by Ventura County .
Comment 66
This section reads as if the source for the borrow has not been determined . If it has beendetermined then permeability data should be included as part of this document and the alterr~tivesanalysis. If the borrow area has not been determined , why not? Infiltration is a key issue withrespect to impact of this proposed project on groundwater . Promising monitoring probes at someunspecified time is not satisfactory . These devices need to be mitigation measures since Boeinghas not characterized the contamination in the fractured rock and has apparently resisted thenotion of a cap or even low permeability backfill (p. 11, par 3, IS) .
[4]
Response
As outlined in the Initial Study and DNWP, the workplan allows for backfilling with soilsfrom an on-site borrow source or, as an alternative , backfilling with soils from an off-site borrowsource. Use of an onsite borrow source is preferred . Approval of the on-site borrow source ispending an amendment to the CUP by Ventura County (refer to Response to Comment 65). Thepermeability for onsite borrow soil is K = 4 .23 x 10 cm/s at 90% compaction . Wan off-site
HDMSP00028175
December 1999p yrResponse to Comments Page 48
•
osal Facilitmer Sodium DisFo
borrow source is used, the borrow soils must be ofsimilar soil type and meet or exceed thepermeability specifications of the onsite borrow source . Control measures for minimizing impactto groundwater are discussed in detail in Response to Comments 1, 4, and 10 .
Comment 6 7
It is interesting to have "clean" imported soil which may contain dioxin to 10 ng/kg--whilethe cleanup number is 13 ng/kg . Perhaps another term could be used instead of clea n(p. 2-7, par 1, IMWP) .
[4 ]
Response
The chemical screening criteria used for fill mate rial at the FSDF is presented inAppendix l of the IMWP . "Clean" backfill soil as used in the workplan refers to backfill soilswhich meet this chemical screening criteria .
Comment 68
Will the backfill soil be tested for the full suite of analytes?
Response
Yes, the backfill will be analyzed for TPH (EPA 8015), 18 metals (6000/7000/7480),dioxin (TCDD-TEQ/EPA 1613B), VOCs (EPA 8260), PCBs (EPA 8082), SVOCs (EPA 8270),ph (EPA 9045), Fluoride (6000/7000), and Gamma radiation .
HDMSP00028176
• Former Sodium Disposal Facility December 1999Response to Comments Page 49
AIRBORNE DUST
Comment 69
What precautions will be taken if the excavation occurs during Santa Ana windconditions?
[1 .m]
Response
In conformance with Ventura County Air Pollution Control District (APCD)recommendations for the project, the following precautions will be taken :
1 . All clearing, grading, earth moving, or excavation activities will cease during periods ofhigh winds (i .e ., greater than 15 miles per hour averaged over one hour) to preventexcessive amounts of fugitive dust .
2. All unpaved on-site roads will be periodically watered to prevent excessive amounts ofO dust.
3 . All active portions of the site will be periodically watered to prevent excessive amounts ofdust .
Air monitoring will be conducted during excavation activities by the Site Safety Officerusing a dust meter . If site activities or weather conditions create dust concentrations greater than1 mg/m3 measured with the dust meter, site activities will be terminated until weather conditionsimprove or until site activities can be modified to reduce airborne dust .
Comment 70
Is there a danger of airborne contaminants resulting from the excavation activities?
Response
Airborne dust contaminants will be minimized using the precautions outlined in Responseto Comment 69. Boeing is also monitoring for background levels of volatile organic compounds(VOCs) using a flame ionization detector (FID) or a photo ionization detector (PU)). In addition
• to the FID or PD, a Draeger pump and indicator tubes may be used to help identify VOCs in thework area if present . Environmental monitoring procedures and Health and Safety precautionsare outlined in Appendix B of the Interim Measures Workplan .
HDMSP00028177
Former Sodium Disposal Facility December 1999Response to Comments Page 50
RADIATION SCREENING
Comment 71
The soil being removed needs to be radiologically screened as well as the metal debris(p. 2, par 2, IS) .
[4]
Response
The Department of Health Services, Radiological Health Branch (RHB) has released theFSDF for unrest ricted radiologic use and has indicated that additional soil screening is notnecessary .
Comment 72
Whose standards were used by the DHS/Radiologic Health Branch to establish that theradiation levels in soils at the FSDF were insignificant ?
[1 .d]
Response
The DHS/Radiologic Health Branch used an annual dose limit of 15 mRem from allpotential exposure pathways as the basis to establish the isotopic soil release concentrations . TheFSDF went through a radiological remediation project lasting from 1991 to 1994 . At thecompletion of the radiological remediation , a final gamma radiation survey and sampling of soiland rock were performed to demonstrate the satisfactory removal of the radioactivecontamination . The gamma radiation survey was summarized in ETEC document number 886-ZR-0007 . To confirm the satisfactory radiological remediation of this area , a sampling andanalysis plan was developed by the Environmental and Energy Group of ICF Kaiser Engineers .ICF Kaiser personnel collected 63 soil samples and 15 rock samples for analysis by ORISE . Noresidual radioactivity above background was found .
On June 10, 1993, RHB collected soil samples from the FSDF , four from the upper pondand four from the lower pond . The results of the laboratory analysis show the samples to haveactivities in the range of background soil .
On July 29, 1996, RHB -RAU collected samples from the lower pond and the gully to theeast of the lower pond along with background samples for comparison with Rocketdyne samplescollected at the same locations .
HDMSP00028178
Former Sodium Disposal Facili ty December 1999Response to Comments Page 5 1
On September 16, 1997, RHB-RAU collected core samples at nine locations from theupper pond and the western area . A total of 25 samples from varying depths down to the bedrockwere sent to the Sanitation and Radiation Laboratory for analysis. The laboratory analyzed forisotopic uranium, isotopic plutonium, strontium , gamma spectra, gross beta and gross alpha. Thesample activity was within the range of the background soil activity .
Comment 73
When was the FSDF released for unrestricted use?
•
•
[id]
Response
On May 6, 1998, the DHS removed the FSDF from California Radioactive MaterialsLicense 0015-19, and formally released the facility for radiological unrestricted use.
Comment 74
Did the unrest ricted residential use release by the DHS/RHB rely on an assumption thatthe site would be occupied by homes in which residents would sleep only in upstairs bedrooms ?
[id]
Respons e
The site was released based on the sampling of the soil and the laboratory analysis of thosesamples . The soil sample activities were within the range of the background soil activities andbelow the specific isotopic concentrations listed in the approved Site-Wide Soil Release criteria .There is no such assumption used in the RESRAD computer code that residents would sleep onlyin upstairs bedrooms .
HDMSP00028179
• Former Sodium Disposal Facili ty December 1999Response to Comments Page 52
TRUCK TRANSPORT
Comment 75
How will the frequency of trucks departing the site be monitored?
•
Response
As stated in the Initial Study and IMWP, the contractor will maintain a Daily Log oftrucks entering and exiting the site to ensure restrictions outlined in the workplan are notexceeded. Upon request, the contractor's Daily Log will be made available to DTSC for review .
Comment 76
How will the trucks be cleaned prior to leaving the site?
Response
The sides of the trucks will be draped with plastic to keep the trucks clean during loadingof soils . The trucks will then pass through the vehicle decontamination area before leaving thesite . If conditions are d ry, dry decontamination of the truck will occur by brushing the tires. Ifwet decontamination is required , the truck will move into a bermed area lined with 20 mlhigh-density polyethylene (HDPE ) . The wheels and truck will be cleaned with a high pressurewasher . Rinse water will be collected in the bermed area and pumped into drums . The drummedwater will be analyzed to meet disposal requirements , and disposed of appropriately .
Comment 77
Is there any possibility the trucks will be radioactive or contaminated ?
•
HDMSP00028180
• Former Sodium Disposal Facility December 1999Response to Comments Page 53
Response
Since the soil sampling results were within the range of the background concentrations,the trucks used to haul the soil excavated from the FSDF should not be contaminated and will notbecome radioactive .
Comment 78
What would be the radius of danger if contaminants were released into the atmosphereduring excavation of the FSDF? What would be the radius of wind blown particulates?
[1 .b]
Response
The radius of airborne particulates are expected to be confined to the immediate vicinity ofthe excavation . As a health and safety precaution, a number of planned control measures, such asthe wetting of soil and covering of trucks, will be taken to reduce the likelihood of environmentalreleases . Air monitoring for dust particles will be conducted . If particulates exceed 1 mg/m3 .(IMWP, Vol . 2 . p B-25, 26), excavation will be halted until dust control measures aresuccessfully implemented . Downwind dispersion of dust particles is not expected to occur .
Comment 7 9
Is there a health risk from haul trucks driving through the neighborhood?
[1 .h, 1 .j ]
•
Response
There is a negligible health risk . Prior to loading , the sides of the dump trucks will bedraped with plastic . Once the soil is loaded, the plastic will be wrapped over the contaminatedsoil in the trucks to prevent loss of pa rticulates, and the top of the trucks secured with a heavycanvas tarp . The trucks will then enter a decontamination zone where the tires will be cleaned .All trucks will comply with State Vehicle Code Section 23114 to prevent spilling of materialonto roads . The precautions being taken will result in zero to minute risks from thechemically-contaminated soil .
HDMSP00028181
Former Sodium Disposal Facility Dooember 1999Response to Comments Page 54
Comment 80
What types of trucks will be used to haul the contaminated soil?
Response
The RCRA or California- hazardous wastes (i .e. mercury contaminated soils) will betransported in closed-top roll-off bins, each with a capacity of 20 to 25 tons. Non-hazardouswaste (i .e., dioxin and PCB contaminated soils) will be transported using 18-wheel end dumptrucks, each with a capacity of 20 to 25 tons of soil .
Comment 8 1
Will the transport trucks be labeled?
Response
All trucks transport ing hazardous waste will be licensed and registered to haul hazardouswaste. Each driver will carry a hazardous waste manifest and trucks will be placarded inaccordance with Department of Transportation (DOT) regulations . Trucks hauling thenon-hazardous waste are not required to carry a placard .
Comment 8 2
Will the drivers and workers conducting the excavation be aware of the type of chemicalsin the contaminated soils?
Response
Each truck driver will be required to have 40 Hour Health and Safety training inaccordance with 29 CFR 1910 . 120 and, other applicable laws. Each truck driver will be providedwith the project Health and Safety Plan which list chemicals and hazards prior to start of theproject. Prior to project startup , the transportation manager will hold a health and safety meetingwith all vehicle operators to thoroughly communicate the Transportation and Health and Safety
HDMSP00028182
I Former Sodium Disposal Facility December 1999
Response to Comments Page 55
Plan to the vehicle operators . Each vehicle operator will acknowledge his understanding of theplans by signing the attendance sheet . New truck drivers assigned to haul hazardous waste willgo through the same procedures prior to being authorized to commence work . The drivers willbe protected per modified level D and each will have a dust respirator to upgrade to level C ifneeded .
Comment 8 3
Is there a contingency plan to maintain moisture in the soils du ring transport toKettleman City landfill ?
[l .k]
Response
Soils will be wetted down during excavation activities to control dust emissions . Once the• soils are loaded into the roll top bins or the trucks, the soils will be covered with plastic drape d
over the sides before loading . The trucks will then be covered with a heavy canvas tarp whichwill be tightly secured . There are no plans to re-wet the soil during transportation toKettleman Hills hazardous waste landfill .
HDMSP00028183
Former Sodium Disposal Facility December 1999
Responseto Comments Page 56
COMMUNITY NOTIFICATION
Comment 8 4
Will the community be notified prior to removal of the 3,200 yards of contaminated soil?
•
[1 .a, 1 .m]
Response
Yes, the community will be notified by mail prior to removal of the 3,200 yards ofcontaminated soil .
Comment 85
Request that a public notice be provided 10 days before excavation activities begin .
[1 .h]
Response
Every effort will be made to provide 10 days notice before excavation activitiescommence.
Comment 86
Will notice be provided to residents along the truck route prior to transpo rt?
Comment 8 7
What is the expected date for excavation activities to begin ?
[Lm)
HDMSP00028184
Fonner Sodium Disposal Facility December 1999Response to Comments Page 57
Response
Excavation activities are expected to begin approximately four weeks fo llowing approvalof the workplan by DTSC .
•
•
HDMSP00028185
Former Sodium Disposal Facility December 1999Response to Comments Per 58
BACKGROUND SAMPLE S
Comment 8 8
Where were background samples collected?
[1 .m]
Response
The background data set used for comparison of FSDF on-site data was collected in theBuffer Zone (south of the Santa Susana Field Laboratory) and in unimpacted areas of the FSDF .Collection of these samples was overseen by DTSC personnel and has been approved by DTSCgeologists and toxicologists .
Comment 89
0 How do you know the on-site background samples were collected in areas free fromcontamination?
[l .m]
Respons e
Background concentrations were not greater than regional California background levelsand did not exceed regulatory guidance levels (Preliminary Remediation Goals) or risk basedlevels (Field Action Levels) which were approved for identifying the lateral and vertical extent ofinorganic contamination .
Comment 90
Why are the background samples collected onsite instead of several miles offsite in areaswhere there is no known contamination?
[1 .m]
Response
A valid background data set must be collected from geologically similar soil formations .These formations may not be present "several miles from the site." Furthermore, levels in
HDMSP00028186
• Former Sodium Disposal Facility December 1999Response to Comments Page 59
background samples are consistent with regional levels and therefore, DTSC has no reason tobelieve that the area where background samples were co llected has been impacted by theoperation at the site .
Comment 91
Why aren't offsite samples used for background samples instead of onsite samples?
•
•
[l .m]
Response
The background data set used for comparison of FSDF on-site data was collected in theBuffer Zone (south of the Santa Susana Field Laboratory) and in unimpacted areas of the FORThese samples were collected from unimpacted areas Representative background samples mustbe collected from geologically similar areas and similar soil types that are unimpacted by siteactivities .
HDMSP00028187
Former Sodium Disposal Facili ty December 1999Response to Comments Page 60
COMMUNITY SAMPLING
Comment 92
Will DTSC be conducting independent sampling in the communities below the FSDF andin communities surrounding the SSFL? Why isn't the State of California willing to pay for offsitesampling?
[1 .c]
Response
A systematic and detailed investigation of all the So lid Waste Management Units(SWMU) and suspected areas where chemicals may have been used, disposed, dumped , or spilledat the SSFL is currently underway. Referred to as a RCRA Facility Investigation (RFI),information collected du ring this investigation will be reviewed to understand the extent ofchemical contamination in each source area, assess their fate (i .e ., windblown, surface watertranspo rt into nearby drainages , infiltration to groundwater, etc.), possible breakdown byproductsor other chemical associations . Based on this data, DISC w ill make an assessment on type ofchemicals which may have most likely migrated offsite , which directions radia lly from the facilitychemical contaminants have moved , types of media impacted, and types of analyses necessa ry toadequately characterize offsite areas potentially impacted by contamination . Once this assessmenthas been completed , a workplan which will adequately and effectively characterize the nature andextent of offsite contamination can be prepared and implemented . Refer to Reponse toComment 94 .
Comment 9 3
How will the limits of contamination around the FSDF be known ?
[I .c]
Response
Refer to response to previous comment .
Comment 94
Has there been a geographic statistical analyses conducted on both on -site and off-site soilS samples .
HDMSP00028188
Former Sodium Disposal Facility December 1999Response to Comments Page 6 1
Response
A statistically valid sampling plan consists of focused (non-random) samples, i.e., visiblystained areas and drainages , and/or samples collected from random locations on a grid . Off-sitesampling, which has been conducted has been focused, with the assistance of the community andstate and federal regulators , to locations where chemical contamination is likely to occur andtherefore , is more likely to detect high concentrations of contamination.
Comment 95
Has some of the sample data been deemed to be out liers and discarded?
[1 .k]
Response
No samples, analyzed for chemical contamination, which have fulfilled the data-qualitycriteria of the quality control/quality assurance program were eliminated from the analyses .
HDMSP00028189
0Former Sodium Disposal Facility December 1999Response to Comments Page 62
TRANSPORTATION ROUTE
Comment 96
After I had mailed the letter to you that I had written regarding removal of contaminateddirt from the Rocketdyne site, along a proposed route of Roscoe Blvd. to Topanga Canyon, Irealized I had neglected to tell you about the shopping center at the corners of Roscoe Blvd . &Topanga Canyon Blvd .
I know I made mention of a major food store (Vons) at this RoscoefTopanga CanyonBlvd. but at the same intersection there is also a Savon , Blockbuster Video , and McDonald's onthe same side of the streets as Vons . On all four corners of that intersection are stores whichgenerate both pedestrian traffic & car tra ffic . The other stores are a Rite Aid pharmacy , gasolinestations, Hollywood Video , and Office Depot . Next to the gasoline station is a Denny'sRestaurant . As you can imagine, I'm sure this helps to generate foot traffic from the apartmentcomplexes nearby as well as automobile traffic .
In contrast , the intersection at Plummer and Topanga Canyon Blvd . has none of this whichis another reason we're proposing the route around the Chatsworth Reservoir .
I hope this additional information will give you fu rther guidance before the decision ismade permanent .
[21]
I am writing in response to the a rticle in the Daily News in regards to removal ofcontaminated soil from Rocketdyne 's Santa Susana Field Lab to central Ca. According to thenewspaper article a route under consideration is that of trucking the soil from the field site toValley Circle & Roscoe Blvd ., transversing Roscoe Blvd. to Topanga Canyon Blvd . and thennorth on Topanga to the 118 Freeway . I strongly oppose this route and would like to voice thereason for my concerns . Our family home is located on the route (one block E . Of Valley Circleand no rth of Roscoe the equivalent of one house) .
Aside from our own personal concerns, I would suggest that either yourself or theappropriate staff personnel drive along the proposed route before a decision is final . They will
readily note that Roscoe Blvd . is major east-west traffic route and that it a heav ily populated
neighborhood of homes . I would like to point out that the intersection of Roscoe Blvd . and
Topanga Canyon Blvd . is heavily congested with both cars and pedest rians, which is where the
trucks would be making the left turn to travel north on Topanga Canyon to the 118 freeway. Myhusband and I have often had to sit at that intersection for 2 stop lights in order to make that left
turn going no rth . Both Roscoe & Topanga Canyon in this area is heavy with traffic . This
intersection also has a number of nearby apartments that are within a block or two of the
HDMSP00028190
• Fames Sodium Disposal Facili ty December 1999Response to Comments Page 63
intersection . I can only surmise that a number of those residents do not have the availabi lity ofcars , which could be one reason for the heavy pedestrian traffic as well as there being a majorfood market at this intersection . There are always numerous cars waiting to go through thatintersection, not only to make the left turn, but also the other lanes . Therefore, I think it isirresponsible to subject people, both on the street and in their cars to be at this juncture, waitingbeside loads of contaminated soil, no matter how carefully it has been covered.
I do propose the alternate route of going around the Chatsworth Reservoir , which is muchless used as far as traffic is concerned and is also much less populated, with much of it being openland until one has traveled most of the way a round the Reservoir . There are also very few cars atthe Plummer St/Topanga Canyon Blvd . intersection at any given time and almost no pedestrians .I would suggest that either yourself or someone from your office personally sit at both thePlummer/Topanga intersection and the Roscoe/Topanga intersection, during the daytime hours,for a period of at least 10 minutes and note the differences .
Thank you for your consideration of the concerns as stated . My husband and I wouldhave been at that public meeting to voice these concerns, had we known about it, before readingabout it in the Daily News . Also, none of our immediate neighbors were aware that such actionswas being contemplated .
[22]
The attached petitions have signatures of concerned residents/consumers that are opposedto the transferring in their immediate residential area(s) of soils that are contaminated with dioxin,PCB's and Mercury that are tentatively schedule to be moved in the month of September for 10days from Rocketdyne 's Santa Susanna Field Lab Fac ility (we would have had more signaturesbut had a short time to get them . )
This environmental error should not be at the cost of the health of these residents whoreside in Simi Valley or San Fernando Valley area.
We propose that since these soils have to be relocated, there are two items we would liketo address :
That they are rerouted through the Chatsworth Reservoir . This route was used two yearsago, therefore, we do not see why they need to take a new route by residents o nTopanga Canyon Boulevard .
•These soils cannot be of safe levels , as the art icle p rinted in the Daily News, datedAugust 8th, 1999 , stated to keep children inside . That alone is a statement of conce rn .
HDMSP00028191
Former Sodium Disposal Facility December 1999Response to Comments page 64
•Most importantly, these soils need to be in scaled containers or sealed trucks . The gestureof safety measures to wet the soil down before the journey in hopes it will not dry andblow off the trucks in unrealistic . Secondly, it is of great concern that the safety measuresalso consist of wetting down the tires so the dust does not carry . This statement showsjust how dangerous this soil is .
•
This is a costly clean up effort that was ordered in 1989 . To subcontract trucks that aresealed transportation would be of great relief to those who may be in the direct area of thesetrucks. Please keep in the mind there will be drivers next to these trucks with their windowsdown on the 118, 405 and 5 freeways . They will be unaware of the contents of the trucks next tothem. And in all reality the dust .will blow off and possibly into their cars.
On Friday, August 13, 1999, a lawsuit was filed by a member of the group Motley Crew,Vince Neil . I believe this lawsuit has direct bearing on these soils . Whether the suit is legit ornot, the fact is the potential health danger could be there .
Unfortunately, we are at the mercy of the people who are in charge of overseeing thisproject . All we can do is voice our concerns . We are the public, the taxpayers, the homeowners,the renters, the voters .
Hopefully, our elected representatives and health depa rtments overseeing this clean upeffort will look out for our best interest in this matter.
[23)
My wife and I are citizens and residents in West Hills and are very upset about theproposed plans to transport toxic materials by our neighborhood in open but tarped dump trucks,18 per day for 10 days as we understand it . The following are reasons why we find the currentplans unconscionable and irresponsible :
1 For some reason, the State and the planners wish to plot a route that goes South toward thedensest, most populated areas and exposes as many people as possible, only to eventuallygo North on Topanga Canyon to the 118 freeway . The obvious and closest route would beto go North through the Box Canyon area where'a short drive would take them to PlummerStreet, which would take them to Topanga Canyon avoiding much of the populated areasand many more miles of driving . I understand there is some concerns about hair-pin turns,but the only ones I'm aware of would be easily navigable if a ll lanes are used and trafficcontrol methodologies are employed . Your current plan seems intent upon exposing asmany citizens as possible to these carcinogenic compounds and for as many miles aspossible . It is incomprehensible . Furthermore, the planned route runs by many more schoolplaygrounds than the Box Canyon route. The Box Canyon route is much more rural andmost of the route finds homes well set-back of street, plus most of the route has no homesalong side it, where the Roscoe Boulevard route has many more homes both oi, the street orclose by .
HDMSP00028192
• Former Sodium Disposal Facility Decemb er 1999Response to Comments Page 65
2. The method of transporting these toxic substances is reckless and irresponsible. It is myunderstanding that the most toxic soils will be placed in steel canisters, while the greatmajority of the soils will merely have an inner and outer tarp . An official has said thatthere is only a very low probability that there could be exposure to our children of theseterrible agents such a dioxin and other carcinogenic substances . However,"I'd keep mykids inside," the official said . Are they kidding? To the greatest degree possible, everyeffort should be made that there is NO RISK to the population as a result of this transportof very dangerous mate rials . Therefore, ALL SOILS should be encased in steel or anencasement that makes any radiation or poisoning virtua lly impossible ! Rocketdyne hascalvalierly played with peoples lives before, are we going to repeat this debacle? Look atwhat's going on here! Since these materials are so dangerous that they have to beremoved from the ground, why are they then being transported from a LESS populatedarea to a MORE populated area (by far)? Let's bring the toxic soil to the people, insteadof keeping it away from them. Does this make sense? The state and the corporationsalready have class-action and other lawsuits that are costing needless monies . Iunderstand a rock star has just opened litigation about the Santa Susana possibleinvolvement in his daughter's unfortunate death from a rare form of cancer . Only the mostthoroughly and well-thoughtout plan which values public safety above money is morallyand fiscally responsible. All soil should be encased in fool-proof and impenetrablematerials and transported away from the population, not toward the population. Thissituation has already been blown once , it doesn't need to be blown again with even morecatastrophic results . The state can't afford more lawsuits which may or may not have afoundation. If you take unassailable precautions regardless of costs , in the long run it willcost all of us less in dollars, and in heartbreak . Every human being has the right to anenvironment free of unnatural toxins and carcinogens ; and to not be killed or harmed bythem by the carelessness and negligence of others . There can be no compromises in thehealth of others, even a lawsuit of millions of dollars does not bring a loved on eSpend the money and do it right . The present route goes by playgrounds which are not faraway. The route and method of transport must be changed .
[28]
On a personal note, I am hopeful you will do everything possible to keep these soils offthe streets .
While collecting the petitions I experienced a lot of concern . Please see the attached noteleft for me by one of the employees at Baja Fresh . The business owners are also concerned aboutbeing in the area for the whole time these trucks will be traveling .
Please keep in touch with me and let me know the status . I will attend any publicmeetings if you need me to .
[24]
HDMSP00028193
Former Sodium Disposal Facility December 1999Responseto Comments Page 66
As per our phone conversation , I am concerned in addition to a ll the other factorsmentioned in my letter to you in regard to the Toxic Substances travelling down Topanga CanyonBoulevard (Interstate 27) . There is now and will be construction on that Interstate that may delaythe trucks or stop them for long periods of time. This is a concern .
[18]
Response
As noted in the wri tten comments above, there were many concerns expressed about theproposed transpo rtation route along Roscoe Boulevard . Among the comments received wereconcerns that contaminated soils and di rt might fall off the trucks along the transporta tion route;the truck traffic would add to the already congested left-tu rn-lane traffic at the intersection ofRoscoe Boulevard and Topanga Canyon - an intersection already congested with pedestriantraffic; the dip in the road on Roscoe Boulevard might be a hazard , and several other trafficrelated issues. Several commenters recommended an alternate route along Plummer , pointing outthat this route was less populated with more open land along the route .
DTSC 's decision is to retain Roscoe Boulevard as the travel route . This decision wasmade after careful consideration of the alternate route and a ll comments submitted . The decisionto retain Roscoe Boulevard was based primarily on traffic safety concerns for haul trucks usingthe Plummer route . Our p rimary concern is that Plummer is a narrow road for trucks tonegotiate . The narrow winding nature of the Plummer road presents a safety hazard for mergingtraffic from the local businesses and homes along portions of the route . Although Roscoe is moreheavily traveled , it is a fully improved four lane roadway , with center tu rn lanes, and parkinglanes . The additional impact to traffic along Roscoe should be minimal since the truck operationsare subject to the following restrictions :
1 . Haul trucks will be restricted to departure intervals not to exceed 15 minute intervals.
2 . Truck operations will be rest ricted to operating in non-peak traffic hours(9:00 a.m. - 3 :00 p . m. and 7 :00 p .m . and 9 :00 p.m.) .
DTSC believes there is no health risk to residents from trucks driving along the Roscoeroute . Soils in excess of the hazardous waste concentrations will be transported in closed top ro lloff bins . Soils below the hazardous waste concentrations wi ll be loaded into 18-wheel end dumptrucks . Prior to loading the soils in each dump truck , the bed and sides of the truck wi ll becovered with visqueen plastic . The soils will be loaded into each truck and the plastic wi ll bewrapped over the top of the soil . Once loaded and wrapped , the load will be covered with aheavy canvas tarp which will be tightly secured . Before departing the site , the tires of each truckwill be cleaned .
HDMSP00028194
•Former Sodium Disposal Facility December 1999Response to Comments Page 67
Comment 97
Will the trucks removing toxic substances be covered to prevent dust & spillagecontamination? What will be the truck routes?
[15]
Response
See Response to Comment 96 .
Comment 98
I was concerned because by taking the Fwy 118 East to Laurel Canyon, to Paxton Street,then to the North Fwy 5 . This was a problem . This area is very congested with ch ildren all daylong. Our local schools are year round because of our student/children population in this area .We have San Fernando High School which is year round and in session now . San Fernando HighSchool is also the only high school in the valley that has day care on site for the infants/children ofthe high school students . These students bring their babies and ch ildren to school with than. Alot of these young mothers walk to school pushing strollers . There's O'Melveny Elementary nextto San Fernando High School . There 's Telfair Elementa ry which session starts the end of themonth . There ' s the Richie Valens Recreation Park. Another park located behind theRichie Valens Recreation Park and the Paxton P ark. These parks are full of people and childrenall day long . I have included a copy of a map of our local area and have marked these locations .
Aside from people congestion at this off ramp, there 's also accident problems all the time .I live on Paxton and I have seen a lot of car accidents occur at the Paxton or ramp going No rth onthe Fwy 5 . There have been deaths. 3-4 car pile ups and cars flipped over. The problem is thatthere are no stops signs between Paxton Street and Arleta. Cars don't slow down and everyone'strying to either get on or off the Fwy and that doesn 't include the traffic trying to turn on Paxtonfrom the side streets . Traffic is a real problem . I've included a copy of the local area so you cansee where our schools and p arks are located .
Like I told you yesterday, I will be seeing Mr . Alex Padilla today at 11 : 00 am . I will passthe information that you have given to me along with a copy of the map route information thatyour going to fax me . I will also inform Mr . Saldivar of our conversations and give him a copy ofthe map too .
Mr. Cain, I was glad that you were able to verify the mapping route, since the reviewpe riod for this projects is up today at 5 :00 p.m., August 19th. After our conversation I wasrelieved when you told me that the map in the paper was wrong . I was glad when you told me
HDMSP00028195
I Former Sodium Disposal Facility December 1999Response to Comments Page 68
that the route would be Fwy 118 to the Fwy 405 north and then onto the Fwy 5 north. This wasa total relief and now I know our children face no danger.
[25]
Response
A newspaper art icle had incorrectly reported the transportation route from the 118 Northto Interstate 5. This would have necessitated the haul trucks exiting the freeway at Paxton Streetto access the 1-5. The trucks will take the 118 East to the northbound 405, and then to I-5North .
•
•
HDMSP00028196
Former Sodium Disposal Facility Dcoember 1999Response to Comments Page 69
GENERAL COMMENTS
•
Comment 99
Compliance with the Los Angeles Regional Water Quality Control Board (RWQCB)Water Quality Control Plan has not been demonstrated . The ground water at this facility appearsto be designated for use as domestic or municipal supply. If this is true, then the ground watermust meet standards established in Title 22 of the California Code of Regulations that, amongother things, restrict dioxin, PCB, and mercury contamination. These restrictions are for allground water at (or near) the site, not just for water at an off site well such as that considered inthe risk assessment . DTSC's decision to restrict compliance to only that resulting from the riskassessment represents an arbitrarily narrow consideration of the environmental impact of theproposed agency action and a failure to assure compliance with all statutory requirements forenvironmental protection. The Initial Study and work plan should establish compliance with theWater Quality Control Plan .
[2]
Response
DTSC 's proposal is not inconsistent with the RWQCB Water Quality Con trol Plan. Theproposed project is an Interim Measure. The focus of the Interim Measure is to remove thesource of contamination . Remediation of groundwater and compliance with the Water QualityControl Plan will be addressed in the final remedy selection process and based upon informationobtained during the RFI .
Comment 100
We request that DISC incorporate the comments, questions, and suggestions we havesubmitted, revise the project documents accordingly, and require more protective mitigationmeasures than those currently proposed . We request that DTSC take no action on the proposedNegative Declaration until the Initial Study and work plan have been revised accordingly .
[2]
Response
DTSC considered all comments received and initiated those revisions DTSC believed tobe necessary.
HDMSP00028197
Former Sodium Disposal Facility December 1999Response to Comments Page 7 0
Comment 101
In closing, we request that DTSC provide a dear, understandable, thorough, andresponsive point-by-point reply to our comments . We also request timely notice of any proposedagency action and all agency decisions related to this facility. .
[2 ]
Response
Comment noted .
Comment 102
DTSC did not provide proper public notice for the July 28, 1999 hearing.
We received only seven days notice of this hearing . We should have been given 45 daysnotice . DTSC officials told us that we could have 45 days notice if we requested it . To allow thisprocess to move forward, we. did not request the cancellation and re-schedu ling of this hearing.
DTSC failed to give proper notification to the media . I spoke with three of the fourrepo rters who regularly cover Rocketdyne issues yesterday and none of them know of thishearing .
The Initial Study does not show any evidence of consultation with any other agencies.DTSC should at minimum, consult with EPA and the RWQCB about the proposed interimmeasure .
The notice I received said that I must make advance rese rvations to view the informationin the repository at DTSC' s offices in Glendale. This requirement violated the requirements ofthe California Public Records Act. DTSC should revise this policy.
[3]
Response
Comment noted.
HDMSP00028198
•
•
Former Sodium Disposal Facility December 1999Response to Comments Page 71
Comment 10 3
The project history provided herein carefully avoids discussing when disposal ofhazardous waste---such as mercury--ceased . This needs to be part of the picture . Did Boeingillegally dispose of hazardous waste after 1982? It does not appear to have had waste dischargerequirements (WDRs ) adopted by the Water Board for such disposal in the impoundment(s) norany Part RCRA application covering the FSDF . This aspect of"project" history should bediscussed as well (p. 1-7, par 6 , IMWP) .
[4]
Response
The Project History outlined in the IMWP is consistent with information provided in theU.SJEPA Final RCRA Facility Assessment (RFA) Report dated May 1994, for the FSDF . TheRFA indicates that the FSDF became inactive in 1976. Limited clean-up activities , radiationsurveys, soil sampling and soil excavations were conducted during 1980-1981 .
Comment 104
The statement that "there are currently no ARARs in soil in California" is not accurate.Porter Cologne has requirements relative to discharge of waste and threat to surface or groundwater. It is held that waste discharge in soils needs to be cleaned up such that it no longerthreatens pollution of surface or ground water . DTSC needs to re-examine this (p. 7-1, par 2,IM Risk Asses .) .
[4]
Response
As part of the next phase of the RFI investigation for the FSDF, supporting agencies willbe asked to provide ARARs. Generally, however, the Corrective Action process is as protectiveof health and environment as supporting agencies ' ARARs .
Comment 10 5
Where was the 10,000 cubic yards of contaminated soil disposed in 1992?
HDMSP00028199
•Fanner Sodium Disposal Facili ty Decanber 1999Response to Comments Page 72
Response
The 10,000 cubic yards of contaminated soil excavated in 1992 was disposed atKettleman Hills Hazardous Waste Landfill, Kings County, California .
Comment 106
Is dioxin contamination at FSDF a biproduct of burning?
•
[ l .b]
Response
Dioxin may be formed during combustion of any organic mate rial in the presence of asource of chlo rine atoms .
Comment 107
Are the dioxin levels at the FSDF a result of natural occurrence ?
Response
Dioxin contamination, which exceeded the risk-based cleanup goal of 13 ppt, will beremoved . It is not possible to identify the source of dioxin which is left in place. However, levelswhich remain are below those identified in a group of samples collected from unimpacted areasthat are well characterized .
Comment 108
Why did Boeing burn the substances at the FSDF?
HDMSP00028200
•Former Sodium Disposal Facility Deccmba 1999Response to Comments Page 73
Response
The FSDF was used to clean metallic sodium from test components used in reactorresearch at the SSFL . The metallic sodium, when exposed to water would react violently andself-combust . Combustible liquids, such as biphenyl oils (PCBs) used as a heat transfer fluid,were placed in the FSDF impoundment and burned . Boeing 's predecessors ' exact motivation forburning combustible liquids in the impoundments is not known.
Comment 109
What was the time period and frequency of the burning?
•
[1 .b]
Response
The FSDF operated from 1956 to 1976 . Information on the frequency of burning is notavailable .
Comment 11 0
Were the burnings permitted?
[1 .b]
Response
The permit history is not known . No permits were issued or required by DTSC duringoperation of the FSDF .
Comment 11 1
Were the burnings done at night?
[1 .b]
Response
The EPA's RCRA Facility Assessment Report, which includes a review of treatmentactivities at the FSDF, does not document whether treatment activities occurred at night .
HDMSP00028201
Former Sodium Disposal Facility December 1999Response to Comments P age 74
Comment 112
Is it a fact that dioxins were found in the residential areas of Bell Canyon ?
Response
Yes, however, the dioxin concentrations did not exceed those of the Bell Canyonbackground area and there was not an indication in the drainage areas of transport from the SSFLfacility .
Comment 113
Where did the emissions go following burning at the FSDF?
[1 .b]
Response
The extent of contamination in soils as a result of chemical use at SSFL is being evaluatedas part of the RCRA Facility Investigation (RFI) currently ongoing at the SSFL.
Comment 11 4
Is groundwater contaminated beneath the FSDF ?
Response
Both shallow and deep groundwater beneath the FSDF has been impacted . The primarilygroundwater contaminant is TCE which was a solvent used to clean rocket engines during testing .Maps and data showing the location and concentrations of groundwater contamination beneaththe FSDF are located in the Annual Groundwater Monitoring Report for Santa Susana FieldLaboratory, which is located in the repositories .
•
HDMSP00028202
Former Sodium Disposal Facility December 1999Response to Comments Page 75
Comment 11 5
I have received and reviewed the above referenced document and find it totally inadequateto place the public on notice of the proposed Interim Measure. The public should not be requiredto visit the Information Repositories or attend the public hearing to learn the specifics of what isbeing proposed, particularly where the most relevant information could have been readily shownon the map enclosed as part of the July 1999 document . In particular, I find the document to bedeficient for the following reasons :
1 . The map is missing major roads , specifically Valley Circle , Bell Canyon Blvd. andSaddlebow . Without these landmarks we can not determine the proximity of the site beingremediated .
2. The community of Bell Canyon , Simi Valley and other surrounding residential areas arenot on the map .
3. The route of the approximately 160 contaminated soil-loaded trucks is not shown; noindication is made of the site of the fill soil and no indication was made of measures toprevent dust from either site from being blown by the prevailing easterly winds intoinhabited areas .
These deficiencies can only be corrected by reissuing a more complete repo rt of actions tobe taken.
[20]
Response
The document referred to was a summary fact sheet . The complete two-volume workplan andone-volume risk assessment are available in the repositories for review .
Comment 11 6
Ahmanson Ranch Public Open Space/ Groundwater Extraction Facility
1 . Ahmanson Ranch is part ially located directly to the west of the Area IV and is the closestproperty to the infamous sodium burn pit . This po rtion of Ahmanson Ranch wastransferred to public ownership in 1998 over the protests of Save Open SpaceiSantaMonica Mountains ("SOS"), in part because no adequate chemical analysis has yet beenconducted on the groundwater , bedrock, and soil of Ahmanson Ranch . SOS is not onlyconcerned about the issues of taxpayer liability for clean-up in the future but also for the
HDMSP00028203
Former Sodium Disposal Facility December 1999
Response to Comments Page 76
public health and safety of the public open space area. Although promised , the recipientagency, Mountains Recreation and Conserva tion Authority, failed to perform any toxicevaluation . In 1996 , Ahmanson Land Company paid for the Phase I Evaluation but failedto inform the consultant that the Santa Susana Field Laborato ry ("SSFL") was adjacent toits property. The misrepresentation was so blatant that the SSFL is identified on the sitemap as "scattered residential ." (See attached portion of the Phase I Evaluation .)
SOS sponsored one chemical study in September 1998 which found Rocketdyne-type
chemical solvents in the surface water of Las Virgenes Creek. These solvents,
1,1-Dichloroethane (DCA) and 1,1,1-Trichloroethane (TCA) are also found on the list of
substances for the existing Monitoring and Report ing Program for SSFL and are not
indigenous to Ahmanson Ranch.
These substances are finger-print chemicals indicating that Rocketdyne chemicals haveprobably migrated from SSFL onto Ahmanson Ranch through the groundwater, bedrock
and or soil . Adequate chemical testing has never been done on Ahmanson Ranch: whenthe issue has been raised during the environmental review of the proposed Ahmanson
• Ranch Project (for which the Public Open Space transfer was required), the answer was
repeatedly that Rocketdyne's test show no off-site contamination . We know now that
adequate chemical testing has yet to be done on the SSFL site and the surrounding
prope rties.
Ahmanson Land Company and Calleguas Municipal Water District had a 1996 agreementto explore the construction of a reclaimed water injection/groundwater extraction facilityin upper Las Virgenes Canyon . The MRCA granted - with no public disclosure ofenvironmental review - the necessary land easements to Ahmanson Land Company .
Studies done by Las Virgenes Municipal Water District for a RegionalExtraction/Injection Facility in the same location indicate that the source of thegroundwater in this area is unknown because the geology of the area is largely unknown .
Although the water would not be considered to be potable, it would be golf courses and
landscaping for the Ahmanson Ranch Project and, potentially, for regional users . Public
health and safety demand that the possible migration of the toxic and radioactive chemicalsfrom SSFL be thoroughly explored before the Ahmanson Ranch Project goes forward.
Ahmanson Ranch Development Specific Plan Area
Ahmanson Land Company intends to build a mini-city on the eastern portion of the
Ahmanson Ranch . Although not directly adjacent to SSFL, it is directly south of
Bell Canyon . Again, no chemical studies have been conducted to determine the potential
for migration.
HDMSP00028204
Former Sodium Disposal Facility December 1999Response to Comments Page 77
In order to develop the extremely hilly area, Alunanson Land Company n*wt grade about72 Rose Bowls full of dirt (50 million cubic yards of soil) resulting in 20,000 tons of dustbeing released into the air. It intends to use the water from Ahmanson Ranch Well #1,located in Upper Las Virgenes Canyon for dust control . In addition to the known hazardof particulates and Valley fever, the development project will further endanger the public'shealth and safety by potentially polluting the surrounding area with Rocketdyne chemicalsif they have migrated into the Ranch soil .
Independent Studies Must Be Don e
For the above reasons , SOS requests that independent studies be conducted for allRocktdyne chemicals and radionuclides including but not limited to uranium , plutonium,strontium, and cesium . The tests should be specific tests for all Rocktdyne chemicals ofthe groundwater , including existing wells on Ahmanson Ranch , bedrock, and surfacewater studies of Las Virgenes and Fast Las Virgenes Creeks at the least .
SOS is also concerned that, in addition to migration of chemical wastes by surface andgroundwater, improper disposal through dumping could have occurred by way of theAhmanson Ranch roads which cross from Rocktdyne because the property lines are notdefined . Various oil and water wells were dug throughout the Ranch at various timeswhich may not have been properly capped .
Wind dispersal of SSFL contamination is also possible since winds blow acrossRocketdyne in all directions depending on the weather and time of year . We know the20,000 tons of dust will be dispersed from Ahmanson Ranch; we don't know how "dirty"it is .
This clean-up must be conducted only as an interim measure and not in any manner whichwill allow the Ahmanson Ranch Company, the MRCA, the water districts or the currentowners of the SSFL the opportunity to claim that the potential for contaminations hasbeen completely removed .
[26]
Response
A systematic and detailed investigation of all the Solid Waste Management Units(SWMU) and suspected areas where chemicals may have been used, disposed , dumped , or spilledat the SSFL is currently underway . Referred to as a RCRA Facility Investigation (RFI),information collected during this investigation will be reviewed to understand the extent ofchemical contamination in each source area, assess their fate (i .e . windblown, surface watertransport into nearby drainages, infiltration to groundwater , etc.), possible breakdown byproduct s
HDMSP00028205
Former Sodium Disposal Facility December 1999Response to Comments Page 78
•
or other chemical associations . Based on this data, DTSC will make an assessment on type ofchemicals which may have most likely migrated off-site , which directions radially from the facilitychemical contaminants have moved , types of media impacted , and types of analyses necessary toadequately characterize offsite areas potentially impacted by contamination. Once this assessmenthas been completed , a workplan which will adequately and effectively characterize the nature andextent of off-site contamination can be prepared and implemented.
Comment 11 7
After soil removal, test , remove and test until acceptable level is obtained. Then tell thepublic "to go home now!"
[5]
Response
Comment noted .
Comment 11 8
Federal regulators overseeing the removal of radioactive waste at a Rocketdyne test lab inChatsworth, Los Angeles, California, are leaving too much contamination in the soil, potentiallyposing a long-term hazard to nearby residents, environmentalists and community leaders .
Standards guiding the U .S . Department of Energy-led cleanup would leave up to 19,0;00times more radioactive residue in dirt at the company's Santa Susan Field laboratory than wouldbe allowed by the U .S. Environmental Protection' Agency .
The Environmental Protection Agency requires any residual wastes left in the groundexpose people to a risk of contracting Cancer be no greater than one chance in 1 million . But theDepartment of Energy would permit enough residual waste to pose a cancer risk as high as one in50. Why is there such a discrepancy?
The Northridge Civic Association feels that we should have this facility cleaned up topristine level whatever the cost is . The residents of San Fernando Valley do not want pollutionfrom this lab to be hazardous to their health .
HDMSP00028206
•Former Sodium Disposal Facility December 1999Response to Comments page 79
Response
Comment noted .
Comment 11 9
I would like to see fruits and plants tested (from the area) also animals that are wild in thearea (blood tissue etc . )
[g]
Response
Comment noted .
Comment 12 0
How about health screening for long term residents . We have been here over 30 years .
[9]
Response
Comment noted .
Comment 12 1
The health of all former SSFL employees should always be a factor .
[10]
Response 122
Comment noted .
•
HDMSP00028207
Former Sodium Disposal FacilityResponse to Comments
Comment 123
Dooember 1999Page 80
I have worked at the field lab for 10 yrs . I am on oxygen at all times.
[11]
Response
Comment noted .
Comment 124
We are interested about the chemical used on the Canoga property .
[12]
• Response
Comment noted.
Comment 12 5
•
I want to know all info on this testing . Both my parents died very young of cancer withno cancer histo ries in either family .
[13]
Response
Comment noted .
Comment 126
Where are the PCB's, dioxin & mercury contaminated soil being moved to? Are you justcreating another toxic site?
[14]
HDMSP00028208
• Farmer Sodium Disposal Facility December 1999Response to Comments Page 8 1
Response
Soils will be transported to Kettleman Dills hazardous waste landfill in Kings County.
Comment 127
Will the trucks removing toxic substances be covered to prevent dust & spillagecontamination? What will be the truck routes?
[15]
Response
Refer to Response to Comment 79 .
Comment 128
I hope this situation is handled with the upmost care considering we, like other residentyoung couples , would like to be able to raise a healthy family here in West Hillsl Ch ildren aremore suspectable to toxins than adults and such a problem as this poses a real threat to thecommunity .
[16]
Response
Comment noted .
Comment 12 9
Have lived here since 1962 and believe a lot of toxic fumes were around when less treesand homes .
[17]
Response
Comment noted .
HDMSP00028209
Farmer Sodium Disposal Facility Daxmba 1999Responseto Comments Page 82
•
Comment 13 0
I would like any and all information you can send me regarding the Santa Susan FieldLaboratory in Southeastern Ventura County as I am ve ry close to the Ventura Co. Line . Otherpeople who lived in this complex have since moved to Simi Valley, but I can give you addresses,but are probably aware of the toxic site of (Boeing/Rocketdyne) Santa Susana Field Laboratory .Again I would appreciate any and a ll information concerning a possible health hazard prob lem if itgets out of control .
[19]
Response
Comment noted .
Comment 13 1
I am opposed to the DTSC granting Interim Measures for the SSFL since :
1 . the Ventura County Air Po llution Control District has not been doing an adequatejob of monitoring Simi Valley' s air for chemicals,
2 . the Los Angeles Regional Water Quality Control Board has not safeguarded the
City's watercourses by allowing Simi Valley to drag its feet on implementing theStormwater Quality Management Ordinance, and not including monitoring stationsbelow the SSFL to assure that contaminated runoff from the SSFL is not adverselyimpacting Meier Creek, Runkle Canyon, and the Arroyo Simi ,
3 . the on-site soil that will be used to fill up the excavated area is not really "clean",
4 . I have no confidence in DTSC coming forward with the truth if remediation goalswere not achieved once the work is completed,
loss of 30% of the plantings is unacceptable, an d
6 . the drip ir rigation must continue past 2000 since many areas of the country areexpe riencing drought conditions which could impact Southe rn California .
0 [27]
HDMSP00028210
• Former Sodium Disposal Facility December 1999Responseto Comments Page 83
Response
Comment noted .
•
Comment 132
How deep and wide is the FSDF area that is being excavated to get rid of thecontaminated soil?
[27]
Respons e
Most of the soils were removed in 1992 . Soils remaining are approximately 4 .5-feet deep .The area of excavation (not including sediments in the drainage channels ) is roughly200-feet by 350-feet .
Comment 133
In 1997, I learned that there were 2 sodium bum pits so I wasn't surp rised to read in therecent Fact Sheet that "In 1992 . . . 10,000 cubic yards of chemical and radionuclide -contaminatedsoil were removed from one of earthen ponds."
The Fact Sheet goes on to say that "Subsequent testing found no evidence ofradionuclides but continued presence of PCBs and dioxin ." What is the status on the othersodium burn pit? What type of contamination has been found in it?
Are there negative impacts when liquid sodium and water mix?
[27]
Response
The FSDF was composed of two impoundments (an upper and lower pond) or pits. Thelower impoundment was declared an impoundment under TPCA by the RWQCB andapproximately 10,000 cubic yards of soils were excavated and transported to Kettleman Killshazardous waste landfill in 1992 . See Response to Comment 12 . The proposed IM Workplanwill remove the remaining contaminated soils from the upper impoundment, area adjacent to theimpoundment, and from the drainages below the impoundments. The contamination found in thelower impoundment is the same as that identified in the upper impoundment .
HDMSP00028211
Former Sodium Disposal Facility December 1999Response to Comments pap 84
The liquid sodium would react violently when exposed to water creating a flammablehydrogen gas. Thus, the name sodium burn pit .
0
Former Sodium Disposal Facility December 1999Response to Comments Page 85
LIST OF CHANGES MADE FROM DRAFT INTERIM MEASURES WORKPLANDATED JULY 9,1999 , TO FINAL INTERIM MEASURES WORKPI.AN
1 . Section 1 .1 .4 will be modified as fo llows :
CEQA compliance has been reviewed by DTSC and a mitigated Negative Declarationfinding made for this Interim Measure.
2. Section 4.1 .3 .3 .2, paragraph 4, will be modified as follows :
One randomly located documentation sample wi ll be collected on each sample grid(established in the FSDF Characterization Report, refer to Section 2.1 .3 and Figure 3-1 ofthis workplan) from the scarified bedrock of the excavation bottom. If field conditionswarrant or if directed by a DISC geologist-biased samples will be collected at locationsof staining or observable signs of contamination . Bedrock samples will be taken using aclean steel hammer to extract chips from the bedrock surface. The bedrock samples willbe placed in clean containers provided by the laborato ry.
3 . Section 4 .1 .3 .3 .3 Sampling and Analysis Procedures - Waste Characterization , paragraph1, will be modified as follows :
Soils will be collected from the excavator bucket during bin loading by driving thestainless steel sampling sleeve directly into the soil . The sampling sleeve will then beret rieved, capped, and labeled . A scoop must not be used to transfer the soil from theexcavator bucket into the samp ling sleeve.
4. Section 4.3 .3 .1 .2 Identification and Testing of Backfill Sources , will be modified toinclude the following statement :
If it becomes necessary to import backfi ll, the imported soil must be of similar soil type tothe onsite borrow source, and meet or exceed the permeability specifications of4 x 10' cm/s when compacted to 90% .
5. Section 4 .3 .3 .1 .4 Backfill Placement and Grading, paragraph 2, w ill be modified asfollows :
Soil will be placed and compacted within 2% of optimum moisture content, to meet4 x 10' cm/s permeability .
•
HDMSP00028213
• Former Sodium Disposal Facility December 1999Response to Comments Page 86
6. Section 4.3.3 .3 .3 Backfill Placement Inspection and Testing, paragraph 2, will be modifiedas follows :
At a minimum. 3 density and moisture content tests will be performed per 6-inch lift in thelower backfill materials .
7. Section 4.3 .3 .3 .3 Back ill Placement Inspection and Testing.
Backfill placement inspection and testing will be modified as follows : Followinginstallation and compaction of the backfill, testing of backfill will be conducted to assessin-situ permeability .
During excavation and backfilling activities, the following dust control measures shall beobserved, as requested by the Ventura County Air Pollution Control Board in a letterdated August 24, 1999 :
•(a) All clearing, grading, earth moving, or excavation activities shall cease du ring
periods of high winds ( i .e ., greater than 15 miles per hour averaged over one hour)to prevent excessive amounts of fugitive dust .
(b) All trucks that will haul excavated or graded material off site shall comply withState Vehicle Code Section 23114 regarding the prevention of such materialspilling onto public streets and roads .
(c) All unpaved on-site roads shall be periodically watered or treated withenvironmentally-safe dust suppressants to prevent excessive amounts of dust .
(d) All active port ions of the site shall be either pe riodically watered or treated withenvironmentally-safe dust suppressants to prevent excessive amounts of dust.
(e) On-site vehicle speeds shall not exceed 15 miles per hour.
HDMSP00028214
mz0x
91A-9 .9 1
HDMSP00028215
•
Appendix M
CEQA Initial Study
•
•
HDMSP00028216
D.W DASSLER
JUL 2 6 1999
CALIFORNIA ENVIRONMENTAL QUALITYAC T
INITIAL STUDYFor
Interim Measure for the Former Sodium Disposal Facility
•
•
The Department of Toxic Substances Control (DTSC) has completed the following InitialStudy for this project in accordance with the California Environmental Quality Act (~21000 et seq., California Public Resources Code) and implementing Guidelines ( ' 15000et seq ., Title 14, California Code ofRegulations). This Initial Study has also been usedto satisfy the requirements of 711.14, Fish and Game Code and 753 .5, Title 14, Code ofCalifornia Regulations relating to filing of environmental fees.
1. PROJECT INFORMATION
Project Name: Interim Measure for the Former Sodium Disposal Facilit y
Site Location : The Former Sodium Disposal Facility (FSDF) is located on the west endof the Boeing North American, Inc., Santa Susana Field Laboratory (SSFL) at the end ofWoolsey Canyon Road in Simi Hills, California . The SSFL is in the USGS Calabasas7.5 minute quadrangle at Township 2 North, Range 17 West . The Santa Susana FieldLaboratory (SSFL) consists of 2668 acres and is subdivided into four administrative areasand a buffer zone . Areas I and III are owned and operated by Boeing North American,Inc., Area II is owned by NASA, and Area IV is owned by Boeing North American andoperated by the Department of Energy (DOE) .
The SSFL is approximately 1,800 to 2,000 feet above sea level and 1,000 feet above thefloor of the San Fernando Valley . SSFL is bordered on the south by a semi-ruralequestrian residential area known as Bell Canyon . The northern perimeter of the SSFL isshared by the Sage Ranch, a public recreational park area owned by the Santa MonicaConservancy, and the Brandeis-Bardin Institute, a minimally-developed parcel used foreducation programs. The eastern-most perimeter of SSFL is bordered by a few smallfarmer ranches and two mobile home parks .
Revised by DTSC, PEAS 7/13/99
1
HDMSP00028217
•
Contact Name/Address/Phone Number
Mr. David DasslerBoeing North American, Inc .6633 Canoga AvenueP .O. Box 7922Canoga Park, California 91309-7922(818) 586-4069
Project Description: The Department of Toxic Substances Control (DTSC) is proposingto approve an interim measure (IM) for the Former Sodium Disposal Facility (FSDF)located within the Santa Susana Field Laboratory (SSFL) . The proposed IM will removeapproximately 3,240 cubic yards of soil contaminated with polychlorinated biphenyls(PCB), dibenzo-dioxins/furans (dioxin), and mercury . The FSDF cleanup goal for PCB is600 ug/kg (parts per billion), dioxin is 13 .1 ng/kg (parts per trillion) . Soil that containsmercury with a concentration greater than or equal to 20 mg/kg (parts per million) will bedisposed as hazardous waste. In addition, any metallic debris encountered will besegregated and screened for radioactivity before disposal, and analysis for perchloratewill be included in the verification samples since it was detected in ground water beneaththe FSDF .
The contaminated soil will be removed from the upper pond, the area to the west of thepond, and three drainages--channel A, channel B, and channel C--that lead away from thelower pond to the north . The depth of soil cover in the pond and western area isapproximately 12 .5 feet and in the drainage channels is less than two feet. The soil inthese areas will be removed down to bedrock. Moreover, in the upper pond and thewestern area, stained weathered bedrock will be scraped off and disposed of The soiland weathered bedrock in the pond and the western area will be excavated using a CAT235 . The soil in portions of channel B and all of channel C will be removed with the useof small hand tools (i .e ., shovels, trowels, broom and dust pan) because the steepness ofthe drainage channels precludes heavy equipment access. The dug soil will be carried outof the drainage channels in buckets, or removed using an industrial dry vacuum truck. Inaddition, stained weathered bedrock in the drainage channels will be removed with handequipment because the heavy equipment required for scraping cannot be placed safely inthe drainage channels .
All excavated soil, weathered bedrock, and metallic debris, if any, will be placed in binsor dump trucks, the hazardous waste kept separate from the non-hazardous waste basedon results from the 1997 characterization study . The contaminated soil will b etransported off-site to Chemical Waste Management, Kettleman Hills for disposal .Excavated soil suspected to be hazardous due to mercury concentrations will be tested formercury once loaded in the bins. Additional analyses for waste characterization for theremainder of the soil will not be performed unless required by the disposal facility prio r
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• to acceptance. At the boundaries of excavation in the upper pond, western area anddrainage channel B, verification samples will be collected and analyzed to confirm thatconcentrations of contaminants are below the cleanup goals .
The excavated areas in the upper pond , western area, and a portion of drainage channel Bwill be backfilled with cle an fill similar to the native soil . It is anticipated that the fill
mate rial will be obtained from an on-site borrow area . However, schedule demands mayrequire import of the backfill soil . Therefore , impacts associated with impo rtation of
backfill material will also be analyzed in this initial study .
The backfill materials will not exceed site background levels for the inorganicconstituents at the SSFL and non-detect for the organic constituents . DTSC has set thisacceptance criteria which allows concentrations of inorganic constituents that areconsistent with the regional background levels . These levels remain protective of humanhealth and the environment and will not significantly impact plant or animal species dueto regional similarities in composition : two times the site background concentration forthe inorganic constituents has been allowed, as the regional background levels are notexpected to exceed this concentration . For organic chemicals, dioxin concentrations up to10 parts per trillion, the background level used on other sites in California ; and motor oilat less than 100 parts per million if the other organic constituents are non-detect, remainsprotective of human health and the environment . The imported soil will be compactedupon placement to reduce the potential for erosion and subsequent migration of sediment
. down the drainage channels. The backfilled areas will then be revegetated with nativeplant species . Inspection and maintenance will be performed annually and followingsignificant rain events up until the implementation of the corrective measures study . Alldamage will be repaired and in the case of recurring damage, materials with a greaterresistance to the damage causing forces will be used.
The proposed IM does not address ecological receptors . However, Boeing NorthAmerican, Inc. will perform a complete ecological risk assessment for the FSDF whenperforming the standardized risk assessment for the entire SSFL .
The IM goals for the Site are aimed at reducing concentrations of chemicals of potentialconcerns such that the Site poses no incremental risk to sensitive human receptors whileat the same time reducing the potential for off-site migration of constituents of concern .
Site HistoryThe FSDF, located on the western end of the SSFL, conducted operations in four majorareas :
1) Concrete pool area ;2) Upper disposal pond;
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3) Lower disposal pond ;4) Western Area .
The concrete pool area, a 42 feet by 12 feet, 15 feet deep pit, was used for staging ofcontaminated equipment . A blast shield, 15 feet by 6 feet, was installed adjacent to thepool area to protect workers while removing sodium and sodium potassium (NaK) fromequipment using steam l ances. Firearms were occasionally used to open containers to theatmosphere ; the contents may have included reactive metals (e.g., Na and NaK), andsolvents (e .g ., trichloroethylene). The pool was drained and the walls were scrubbedclean .
The Upper and Lower disposal ponds were unlined earthen-bermed areas used tocomplete treatment of sodium -contaminated equipment by reaction with water to ensurecomplete reaction of sodium we tted components . Several of these components were leftin the ponds and covered with soil . When the components were removed , they werefound to contain small amounts of un-reacted sodium .
The western area was used to stockpile soil from the ponds . Some soil was reported tohave been excavated and transported off-site for disposal .
In the 1970s , the FSDF disposal ponds were cleared of residual debris such as pipes,machined metal parts and tubes ; however, some metal components were left in place . In1977, the access gate to the FSDF w as locked, with only documented items and materialsallowed to be placed in the ponds .
In 1977 , a new Hazardous Waste Management Facility for sodium contaminatedcomponents was constructed, resulting in reduced use of the FSDF . The FSDF concrete-pool area was drained of water and the radioactive contaminated walls weredecontaminated. The unlined impoundments (disposal ponds) were surveyed forradiation . The survey detected radioactive contamination in the Lower pond . Localizedareas with higher levels of radiation were decontaminated.
In 1980 , a radiation survey of the Lower Pond identified cesium-37 as the primarygamma emitter . Naturally occurring radionuclides were also detected . In 1985, soilinvestigations were performed at locations suspected of being contaminated . In 1987, aComprehensive Environmental Response Compensation and Liability Act (CERCLA)Phase II Site Characterization study was performed . During the Phase II study, 23trenches were excavated to collect and analyze soil samples to define the vertical extentof contamination and identify potential migration pathways . In May 1988 , a DOE surveyidentified areas of chemical contamination in soil and/or ground water .
In 1990, the Regional Water Quality Control Board , Los Angeles Region (LARWQCB),determined that the Lower Pond of the FSDF was a Toxic Pit Control Act (TPCA)surface impoundment . The Department of Energy (DOE) and Rocketdyne prepared a
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Hydrologic Assessment Report which concluded that the FSDF was a potential source ofgroundwater contamination . In April 1991, LARWQCB issued Clean-up and AbatementOrder No. 91-061 to Rocketdyne and used their blanket exemption from the provisions ofthe California Environmental Quality Act (CEQA) . A Closure Plan was submitted to theLARWQCB to address the Lower Pond, Upper Pond, and Western Area . In June 1992,the Closure Plan was approved and all soil was excavated from the Lower Pond only .LARWQCB agreed to TPCA closure on the condition that the Lower Pond would bebackfilled to control surface water . LARWQCB then deferred the site cleanup to DTSC .
In August 1997, DOE and Rocketdyne completed characterization of the extent of theradioactive and chemical content of soil at the FSDF . The data showed that radioactivityat the FSDF was at background levels . The Department of Health Services, RadiologicHealth Branch collected verification samples and released the FSDF for Unrestricted Use .The organic and inorganic constituents however, were elevated. These chemicals areconsidered constituents of potential concern (COPC) and are being evaluated for risk tohuman health and the environment . The draft final risk assessment for the FSDFdetermined that the COPC are PCB, dioxin, and mercury. The concentrations of COPCdetected at the FSDF for mercury is up to 25 mg/kg, PCB up to 27 mg/kg, and dioxin upto 423 pg/kg .
In September 1997, DOE and Rocketdyne submitted an amendment to the 1992 ClosurePlan to DTSC which included the Upper Pond, western area, and drainage channels .DTSC determined that the Closure Plan approved by the LARWQCB was not designed tomeet the Resource Conservation and Recovery Act Corrective Action and CaliforniaEnvironmental Quality Act requirements and rescinded its approval . DTSC requestedthat a Workplan be submitted for an Interim Measure for soil removal to prevent furthermigration of contaminants to ground water and down the drainage channels .
Agencies Having Jurisdiction Over the Project/Types of Permits Required:
The project is being implemented under the direction of the State of CaliforniaEnvironmental Protection Agency, Department of Toxic Substances Control pursuant toHealth and Safety Code Section 25355 .5(a)(1)(C). The removal action will be conductedunder an approved Interim Measures Workplan pursuant to Section 25356 .1 (b) and (h) ofthe California Health and Safety Code and Title 40 Code of Federal Regulations Section300.415 . This removal action is consistent with Health and Safety Code Section 25358 .9,and will therefore not require a Hazardous Waste Facility Permit.
The County of Ventura requires a permit for excavation and grading activities . Boeingapplied for and received a permit for these activities in the Upper Pond, Lower Pond andwestern area in September 1992 when cleanup activities were being conducted under theLos Angeles Regional Water Quality Control Board. A Grading Permit Modification willbe required by the County of Ventura to cover an on-site borrow source .
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IL DISCRETIONARYAPPROVAL ACTION BEING CONSIDERED BYDTSC
❑ Initial Permit Issuance ❑ Removal Action Pl an
❑ Permit Renewal ❑ Removal Action Workplan
❑ Permit Modification ❑ Inte rim Removal
❑ Closure Plan Other (Specify)
❑ Regulations Interim Measure
Program /Region Approving ProjectCalifornia Environmental Protection AgencyDepartment of Toxic Substances ControlCroydon Office
Contact Person/Address /Phone NumberGerard Abram sDepartment of Toxic Substances Control10151 croydon Way, Suite 3Sacramento, California 95827-2106(916) 255-360 0
III. ENVIRONMENTAL CONDITIONS POTENTIALLYAFFECTED
❑ Earth ❑ Risk of Upset ❑ Aesthetic s
0 Air ❑ Transpo rtation/Circulation ❑ Cultural/Paleontological Resources
❑ Surface and Groundwater ❑ Public Se rvices ❑ Cumulative Effects
❑ Plant Life ❑ Energy ❑ Populatio n
❑ Animal Life ❑ Utilities ❑ Housing
❑ Land Use ❑ Noise ❑ Recreatio n
❑ Natural Resources ❑ Public Health and Safety
IV ENVIRONMENTAL SETTING/IMPACT ANALYSIS
The following pages provide a brief description of the physical environmental conditionswhich exist within the area affected by the proposed project and an analysis of whether or
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not those conditions will be potentially impacted by the proposed project . Preparation ofthe Environmental Setting and Impact Analysis sections follows guidance provided inDTSC's Workbook For Conducting Initial Studies Under the California Environmentalquality Act C( EQA) [Workbook] . A list of references used to support the followingdiscussion and analysis are contained in Attachment A and are referenced within eachsection below.
Mitigation measures which are made a part of the project (e .g: permit condition) or whichare required under a separate Mitigation Monitoring Plan which either avoid or reduceimpacts to a level of insignificance are identified in the analysis within each section.
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1 . Earth (Workbook ; page 11 )
Description o fEnvironmental Setting;
The Santa Susana Field Laboratory is located in the Simi Hills of eastern VenturaCounty, California (Figure 1). The Simi Hills are in the northern part of the TransverseRange geomorphic province and separate Simi Valley from the western part of the SanFernando Valley . Simi Valley is a broad east-west trending synclinal depression withSimi Hills forming its southern flank .
The Simi Hills consist primarily of exposures of the Upper Cretaceous ChatsworthFormation. Massive, cliff-forming sandstone beds of the Chatsworth Formation are thepredominate exposure in the Simi Hills .
Chronologically, the geologic units consist of the Upper Cretaceous ChatsworthFormation, Tertiary Martinez Formation, Tertiary Topanga Formation, and QuaternaryAlluvium .
Chatsworth Formation
The Chatsworth Formation is a marine turbidite sequence with three members . The lowermember consists of interbedded brown shale and light brown calcareous sandstone and is210 feet in thickness southeast of Dayton Canyon . The lower member is unconformablyoverlain by the Topanga Formation in Dayton Canyon . The middle member is composedprimarily of buff colored arkosic sandstone with thin interbeds of brown shale andconglomerate and is 5,080 feet thick . The upper member is a tan colored arkosicsandstone with light bluish-gray to brown shale and pebble conglomerate and is 800 feetthick .
The middle member is the only member exposed at the SSFL except for the southeasterncorner of the SSFL where the lower member is exposed . The Chatsworth Formation bedsstike northeasterly and dip toward the northwest . The beds dip approximately 20 to 30degrees to the northwest and exhibit well developed fractures and joints . Apparent in theoutcroppings are two fracture sets : one oriented approximately perpendicular to bedding,striking northeast and dipping southeast; the second set striking north-northwest anddipping toward the northeast . To the northwest of SSFL the Chatsworth Formation isoverlain by the Tertiary Martinez Formation .
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• Martinez Formation and Topanga Formatio n
The Martinez Formation is composed of marine sandstones and shales with a basalconglomerate . Exposures of the Martinez Formation occur to the north and northwest ofSSFL and in an area of SSFL south of Burro Flats .
The Topanga Formation is composed primarily of bedded marine sandstone with a basalconglomerate . Exposures occur to the southeast of the SSFL .
Alluvium
Quaternary alluvium consists of unconsolidated sand, silt and clay, with a thickness of 20feet in some areas . Alluvium overlies the Chatsworth and Martinez Formations as thindiscontinuous layers, occurring in Burro Flats and along ephemeral drainages .
The FSDF is located in Area IV (Figure 2) in rocky terrain and is bounded on the east andwest sides by massive sandstone beds of the Chatsworth Formation . Limited overburdenoccurs at depths of zero to 12 .5 feet below ground surface . Several major faults in thearea offset the Upper Cretaceous Chatsworth Formation . The Burro Flats Fault trendsnorthwest-southeast and passes within several hundred feet of the FSDF . Thesouthwestern block of the fault appears to be down-thrown relative to the northeasternblock. It is not known if strike-slip movement along this fault has occurred . Fracture
• patterns in the Chatsworth Formation have been mapped using aerial photography andfield methods . Predominant fracture trends are approximately north 45 degrees east andnorth 70 to 90 degrees west . Surface drainage from the FSDF is primarily via two naturalchannels that trend in a northerly direction, converging near the SSFL boundary . Soiloccurs in the ponds and western areas to depths of two- to approximately 12 .5 feet and inthe drainage channels to less than two feet in depth . This soil will be removed anddisposed of off-site . In the event that contamination stained weathered bedrock isencountered in the ponds and western area, it will be scraped off and disposed of off-site .
Ref: RCRA Facilities Investigation Workplan Addendum, Santa Susana FieldLaboratory, Simi Valley, Ogden Environmental and Energy Services, Inc .(September 1996) .
Draft Final Former Sodium Disposal Facility Santa Susana Field LaboratoryCharacterization Report, ICF Kaiser Engineers (August 15, 1997) .
Draft Final Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory , ICF KaiserEngineers, Inc . (June 18, 1999) .
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Geophysical and Hydrologic Testing Surveys, Rocketdyne/Santa Susana FieldLaboratory, Ventura County, California, Harding Lawson Associates(November 2, 1995 )
Analysis potential impacts
Excavation of contaminated soil. Soil will be removed down to bedrock from five areaswithin the Site : the upper pond, western area, Channel A, Channel B, and Channel C(Figure 3). It is anticipated that approximately 3,240 cubic yards of soil will be removedwith a backhoe. Soil along the perimeter of the upper pond and western area, and thelower portion of drainage Channel B will remain undisturbed . The IM activities will notcause instability of soil around the perimeter of the pond, western area, or drainagechannels because of the shallow soil depth. The topography is such that the bedrockforms a bowl with a thinner cover of soil at the perimeter and deeper soils in the center ofthe pond. Within the channels are thin, discontinuous alluvium deposits withconcentrations of contaminants that will continue to migrate down slope towards theBrandeis-Bardin property boundary if not removed . In the event that contamination-stained weathered bedrock is observed in the pond or western area, the backhoe will beused to scrape off the surficial few inches of the weathered bedrock . The excavated soiland weathered bedrock will be placed in bins, covered, and transported to an off-sitelocation for disposal .
• Excavation of back-fill soil from on -site borrow pit . Rocketdyne will develop an on-site borrow area to obtain the 13,000 cy of fill material necessary for backfilling theexcavation. Excavation activities will be in accordance with a Ventura County permit(Permit No . 8664) . Both a biological impact analysis and a cultural resource assessmentof the proposed borrow area have been done . The biological impact analysis concludesthat the construction of the borrow area could not have a significant impact on theenvironment . The cultural resources survey concludes that no cultural resources arelocated within the borrow area site . The perimiter grading lines will be kept a minimumof 10 feet from the coastal sage scrub of the adjacent slopes on the north, south, and eastperimeters of the meadow . Dust control will be maintained by spraying water using awater truck or by application of dust palliatives. At the end of the excavation season, thedisturbed area will be brought to final grade and revegitated with a native seed mixconforming to the County recommendations for the Santa Monica Mountains .
Back-filling excavated areas . The excavated areas in the upper pond, western area, andthe upper (southern) portion of Channel B will be backfilled, with clean fill that is similarto native soil . The backfill materials will not exceed site background levels for th einorganic constituents at the SSFL and non-detect for the organic constituents. DTSCwill allow regional levels of inorganic constituents as these levels remain protective ofhuman health and the environment and will not significantly impact plant or animalspecies due to regional similarities in composition . For organic chemicals, dioxin
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concentrations up to 10 parts per trillion, the background level used on other sites inCalifornia is allowable ; and motor oil at less than 100 parts per million if the otherorganic constituents are non-detect is acceptable as this level remains protective of humanhealth and the environment .
The backfilling activities will be in accordance with the requirements of the gradingpermit issued by Ventura County . The permit conditions include : deleterious andunsuitable material to be removed from all areas to receive compacted fill ; approval ofimported materials by the soils engineer and County of Ventura; excavation baseconfiguration must support potential planes of failure; all areas are to be inspected by theengineering geologist and soils engineer prior to placement of fill materials ; grading to beperformed in accordance with the Uniform Building Code-91, Chapter 70 (update UBC-94, Chapter 33) ; and protection of all graded surfaces from erosion .
Boeing will provide the permeability data for the imported soil to DTSC . Aftercompletion of the excavation and backfilling, monitoring probes will be installed in theareas where fill material has been placed to determine if water infiltration is occurring .This information is needed to determine the final remedy for the FSDF .
Following excavation and backfilling activities, the FSDF will be restored to its pre-construction condition by re-vegetation with native plant species .
The drainage channels are considered riparian areas . The contaminated soil to b e• removed will be replaced with clean fill material having similar composition . The impact
is short in duration and will be minimized by replacing contaminated soil with clean fill .The impact to Channels A and C which will not receive fill materials is temporary andsediments are expected to reestablish themselves after a few rain events .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory , ICF KaiserEngineers, Inc. (April 24, 1998) .
Conditional Use Permit for Environmental Cleanup of the Former SodiumDisposal Facility, Boeing North American, Inc ., General Notes, VenturaCounty, California (September 8, 1992) .
Grading Permit Modification, FSDF Interim Action, Rocketdyne Santa SusanaConditional Use Permit 248 : Permit No . 8664, Ventura County Air PollutionControl District (June 1999 )
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Findings :Potentially
Potentially Significant Less ThanSignificant Unless Significant No
a O O O
S
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2. Air (Workbook ; page 13 )-------------------------------------------------------------------------------------------------------------
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Description gfEnvironmental Settin :
The FSDF is located in southeastern Ventura County, the inland portion of the OxnardPlain Airshed. Predominant wind patterns follow a diurnal land/sea breeze cycle, withtypical daytime winds from the west . Frequent temperature inversions tend to trappollutants thereby inhibiting dispersion . Photochemical reactions of the trappedpollutants create ozone.
Within Ventura County, the Ventura County Air Pollution Control District (VCAPCD) isthe regulatory and planning agency required to monitor emissions and develop and updateplans to demonstrate how the air quality standards will be met . Areas that do not meetthe federal and state clean air standards are designated as "non-attainment" areas . Thesouthern portion of Ventura County is in the category of non-attainment for the Statesuspended particulate matter (PM10) standards and the Federal and State ozone (03)standards. However, Ventura County is in attainment with the Federal and Statestandards for carbon monoxide (CO), oxides of nitrogen (NOx), oxides of sulfur (SOx),and the Federal standard for PM10 .
For emissions from mobile sources, the VCAPCD has set threshold values for reactiveorganic compounds (ROC) at 25 pounds per day and for NOx at 25 pounds per day .VCAPCD further specifies that construction related emissions of ROC and NOx are notcounted toward these two significance thresholds due to their temporary nature .However, if estimates indicate that these thresholds may be exceeded, mitigationmeasures should be specified. Such mitigation measures are identified in the analysissection .
Precipitation is measured at the Ventura County Rain Gauge Number 249, located in thenortheast portion of the SSFL . The mean annual precipitation at SSFL is approximately18.6 inches, the majority of the precipitation occurring during January through March .
Ref: City of Simi Valley General Pl an, City of Simi Valley (Adopted October18, 1988) .
Ventura County Air Pollution Control District , personal conversation withDouglas Tubbs on attainment status for the ambient air quality standards(August 26, 1998) .
Ventura County Air Pollution Control District, Correspondence on ThresholdEmissions from Short Duration Construction Projects (June 29, 1999) .
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Guidelines for the Preparation of Air Quality Impact Analyses , Ventura CountyAir Pollutions Control District (October 24, 1989 )
Analysis pfPotential Impacts
Excavation and soil moving activities may generate fugitive dust emissions , however,dust suppression measures will be implemented . Water will be applied to the soil beforeexcavation and during loading of soil into the bins . Hand held dust monitors will be usedto measure the opacity . The Ventura County Air Pollution Control District (VCAPCD)requirements applicable to this project include Rule 50 (restrictions on the emission of aircontaminants that have opacity darker than No. 1 on the Ringlem an Chart), Rule 51(restriction on the emission of air contamin ants which cause injury, detriment, nuisance,or annoyance), and Rule 74 . 29 (restriction on aeration of soils containing g asoline , dieselfuel, or jet fuel that me asure greater than 50 ppm by volume on an organic vaporanalyzer) . These rules will be complied with to mitigate impacts during implementationof the Interim Measures Work Plan for the FSDF . The project will comply with theVCAPCD opacity and nuisance requirements . Volatile organic compounds are notexpected but monitoring will be performed during excavation using an organic vaporanalyzer.
One CAT 235 excavator will be used for the removal and loading of soil into bins .
Trucks will arrive at the site to transport the contaminated soil off-site . The route will be
S on the s treets in the City of Los Angeles under the jurisdiction of the South Coast AirQuality Management District (SCAQMD) . SCAQMD stated that no restrictions will beplaced on this project with regard to emissions from truck traffic transporting thecontaminated soil to the off-site disposal facility if the Level-of-Service standards are notlowered. Mitigation measures will be implemented for transportation so that the Level-of-Service will not be lowered . Transportation will occur during non-peak hours for theintersections along the route (see 9 . Transportation/Circulation) .
Following excavation and transportation of the contaminated soil off-site, excavationfrom the borrow area and back-filling the FSDF will begin . Excavation activities in theborrow area will be performed with a bulldozer (Cat . D-6), loader (Cat . 966), andapproximately four 15 cy end dump trucks . The borrow soil material will be dumped inthe FSDF excavation area and compacted using a 20 ton compactor (Cat 815) .
As stated in the setting, the VCAPCD exempts contraction related emissions of ROC andNOx from significance threshold calculations since the emissions are temporary . Inaccordance with VCAPCD guidance, DTSC has adopted mitigation measures to reduceimpacts to AIR to a less then significant level . The mitigation measures include :
1) Maintaining equipment engines in good condition and in proper tune as permanufacturer's specifications.
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2) During smog season (May through October), the construction period should belengthened so as to minimize the number of vehicles and equipment operating atthe same time .3) Construction activities should utilize new technologies to control ozoneprecursor emissions as they become available and feasible .4) Limiting transportation activities to non-peak hours for removing contaminatedsoil from the site .
Should it become necessary to import fill soil from an off-site source, transportationactivities will be limited to non-peak hours or the number of daily truck trips will belimited so that daily vehicle emissions will not exceed the projected daily Nox emissionsfor non-peak hour transportation (350 lb/day) . To meet this standard will require limitingthe number of trucks entering and leaving the site during peak traffic hours and extendingthe duration of the transportation activity . These mitigation measures have beenincorporated into the IM Workplan .
Due to the short duration of the project (12 weeks) and the implementation of mitigationmeasures, the project will not degrade any air resources which will individually orcumulatively result in a loss of biological diversity among the plants and animals residingin the air.
Ref: Draft 1998 Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory, ICF KaiserEngineers, Inc . (April 24, 1998) .
Ventura County Air Pollution Control District , Correspondence(September 16, 1998) .
South Coast Air Quality Management District , Personal conversation withJonathan Nadler (August 1998) .
Guidelines for the Preparation of Air Quality Impact Analyses, Ventura CountyAir Pollutions Control District (October 24, 1989)
Findings:
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PotentiallyPotentially Significant Less ThanSignificant Unless Significant No
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3 . Surface and Ground Water (Workbook; page 17)
Description gfEnvironmental Setting:
The FSDF is located in the Calabasas 7 .5-minute Quadrangle (USGS 1987) . SSFL is notwithin a 100-year flood plain . SSFL is located at an elevation of approximately 1,800feet above sea level . The highest 100-year flood level projected for the valley areas oneither side of SSFL site is an elevation of approximately 1,200 feet . In the northernportion of the SSFL, an east-west trending ridge separates the Santa Clara River Bas infrom the Los Angeles River Basin . South of the surface water divide , runoff flows toBell Canyon Creek which joins the Los Angeles River channel just west of Canoga park .The flow continues east into the Sepulveda Flood Control Basin , then south through Los
Angeles to the Pacific Ocean at Long Beach. North of the surface water divide, waterflows down drainages (Figure 3) through the Brandies-Bardin Institute and Sage RanchPark properties, ultimately to Meier Canyon, where it converges with runoff from RunkleCanyon to form Calleguas Creek . Calleguas Creek flows southwest to the Pacific Oceanat Point Mugu. Approximately 16 percent of the SSFL surface area drains to the north,65 percent to the south, 18 percent to the east into Dayton Canyon, and one percen tto the east into Woolsey Canyon . Surface water at the FSDF is seasonal , with drainagesreceiving water only during the rainy season . Surface water from these drainages flowinto and are approximately 1,000 feet upslope from a blue line stream . Residents arelocated to the south and east of the FSDF and do not receive run-off from these drainagesas they are located north of the surface water divide and flow to the north toward theBrandeis-Bardin Institute .
Two groundwater systems occur beneath the site : 1) a shallow groundwater system in thesurficial alluvium, underlying zones of weathered sandstone (with interbeddedsiltstone/claystone), and isolated fracture systems ; and 2) a deeper regional groundwatersystem in the fractured Chatsworth Formation . The two systems appear to behydraulically connected . The shallow zone hydrogeologic unit is laterally discontinuousand occurs primarily in the Burro Flats area and along ephemeral drainages . In general,the depth to groundwater in the shallow zone ranges from just below ground surface to 30feet and occurs under unconfined conditions . Ground water within fractures of theChatsworth Formation occurs under both confined and unconfined conditions, thesaturated thickness is not known . In November 1997, the static depth to ground water inthe Chatsworth Formation groundwater monitoring wells at FSDF ranged from 212 .14 to361 .05 feet .
Groundwater monitoring wells located at the FSDF have shown detections of solvents,notably trichloroethylene, and perchlorate .
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Ref: Groundwater Remediation Operations Workplan, Boeing North American, Inc .,Rocketd_yne Propulsion and Power, Santa Susana Field Laboratory, Areas I & III(May 25, 1990, Revised April 21, 1998), P . IV-I .
Annual Groundwater Monitoring Report, Santa Susana Field Laboratory ,1997, Groundwater Resources Consultants, Inc . (February 25, 1998)Pp. 16, 1 9
Public Participation Plan for the Closure of the Former Sodium Disposal Facility,Santa Susana Field Laboratory (July 1991), Ebasco, Pp . 5,6 .
Analysis pfPotential Impacts
Surface water from the FSDF area flows into drainage channels A and B then convergeswith other drainages into channel C. Surface water flow is seasonal, generally occurringonly after a rain event . Since project implementation will be performed during the dryseason, flooding will not have an impact . The surface water flow is seasonal and ifpresent during implementation of the project, will be temporarily diverted to the east intoa drainage that also converges with drainage channel C . The proposed IM activities ofsoil removal and transport to an off-site disposal facility, backfilling of the ponds,western area, and a portion of channel B with materials similar to native soil, andrevegetating the area with native plant species are anticipated to take three months tocomplete . After IM completion, surface water will not be diverted away from drainag e
• channel B. The IM will not permanently alter any water resources because the diversionof the surface water will be short term, the channel which water is diverted to flows intothe same channel that channel B flows into, and surface water is seasonal, usually beingpresent only in winter months . The proposed IM activities are scheduled to end beforethe rainy season. The removal of the soil from the FSDF and drainage channels willremove the contaminants that may potentially expose receptors to the north . Therefore,no impact to sensitive receptors will result from this project .
The drainage channels are considered riparian land . Contaminated soil will be removed .The project is temporary, anticipated to take approximately three months to complete andthe riparian area will be restored to its preconstruction condition . The Californi aDepartment of Fish and Game (DFG) will determine if a stream alteration permit isnecessary for the proposed removal action for the drainage channels prior toimplementation of the IM . If DFG determines that a stream alteration permit isnecessary, the requirements during project implementation will be specified in the permit .
The Interim Measure goals at the FSDF are aimed at reducing both the concentrations ofchemicals of potential concern and migration of pond sediments to the drainage channels .The end result being that the FSDF will no longer pose incremental risk to sensitive
human receptors above background or a risk-based level . The depth of excavation is
. Revised by DISC, PEAS 7/13/99
17
•approximately 12 .5 feet or down to bedrock . The shallow ground water beneath the
FSDF occurs at a depth of 28 . 69 feet below ground surface, therefore ground water willnot be directly affected by project implementation . The excavated areas of the pond and
a po rtion of channel B will be backfilled with clean soil . The final grade of the fill
materials in the ponds will be such that surface water will flow away from the center of
the ponds .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the Former
Sodium Disposal Facility . Santa Susana Field Laboratory , ICF Kaiser
Engineers , Inc. (June 18 , 1999) .
California Department of Fish and Game, Personal conversation with
Mary Meyer (September 22, 1998) .
•
Findings :
Revised by DISC , PEAS 7113199
18
Potentiallyx O
4. Plant Life (Workbook ; page 20)
Description ofEnvironmental Setting:
The SSFL occupies approximately 2,668 acres of hilly terrain with approximately 700feet of topographic relief near the crest of the Simi Hills . The lands to the north and westare designated "open lands" by the County of Ventura . On-site vegetation includes theSouthern California Black Walnut, Valley Oak, and Santa Susana Tarplant and thefollowing habitats : non-native grasses, Venturan Coastal sage scrub, coast live oakwoodlands, chaparral and ruderal (introduced species that can withstand frequentdisturbance and/or has been disturbed by human activity) .
Ref: Biological Conditions Report, Santa Susana Field Laboratory, Ventura County,California , Ogden Environmental and Energy Services, (June 1997) .
Natural Diversity Data Base, Special Pl ants, California Department of Fishand Game (April 29,1998) .
•
0
Analysis pfPotential Impacts :
The project involves removal of approximately 3,240 cubic yards of earth from five areaswithin the FSDF. One sensitive plant species, the Southern California Black Walnut andone rare plant species Santa Susana Tarplant, are located at the FSDF and near thedrainage channels . Measures will be taken to avoid any excavation within the drip line ofthe Southern California Black Walnut or the Valley Oak . A fence will be placed aroundthe trees to ensure their protection . The Santa Susana Tarplant was observed near thedrainage channels which are being proposed for excavation . A characteristic of the SantaSusana Tarplant is that it grows out of crevices in rock outcrops above the soil line .Because the proposed project will remove soil and contamination-stained bedrock belowthe soil line, this plant species will not be impacted . To ensure that the Santa SusanaTarplant is not disturbed, a brightly colored flag will be placed adjacent to the plants tomark their location. Workers entering and exiting the drainage channels will walk aroundall flagged plants and use hand tools to remove soil . The southern portions of drainagechannels A and B allow access to heavy equipment. Access points for the heavyequipment will be in a location that will minimize impacts to these plant species .
Field surveys conducted in May 1999, found that two species listed under the FederalEndangered Species Act occur or could occur on the site of the proposed borrow pit :Braunton's milkvetch (Astragalus brauntonii) and California gnatcatcher (Polioptilacalifornica) . Braunton's miklvetch is listed as endangered . and the California gnatcatcheris listed as threatened. Three individuals of Braunton's milkvetch were observed in theimmediate vicinity of the proposed access road to the site. However, the access road
Revised by DISC, PEAS 7/13/99
19
HDMSP00028235
alignment was staked in the field as part of this study to avoid loss of this species. Inaddition, orange safety fencing will be installed between the access road and each plant,and construction of the access road will be monitored by a qualified biologist .
Suitable habitat (coastal sage scrub) for the California gnatcatcher occurs around theperimeter of the project site . However, the nearest known breeding site for this species islocated 11 miles to the northwest, and the boundaries of the project site were selected toavoid and provide a 10 foot buffer from this habitat . The proposed access road wouldresult in loss of about 0 .02 acres of suitable habitat for this species . Due to the lack ofsightings of the California gnatcatcher in the project area, and very small habitat loss,significant impacts to this species is not expected.
Implementation of control measures discussed above, will reduce the impact to the plantspecies to less than significant . Moreover, the Department of Fish and Game (DFG) hasbeen informed about the occurrence of the Santa Susana Tarplant near the drainag echannels and has agreed that these measures will minimize impacts to the plant species toless than significant . No other plant species of concern occur at the FSDF . The FSDFponds and western area will be revegetated with native plant species after the IM has beencompleted .
The California Department of Fish and Game Natural Diversity Data Base Special Plantslist, which identifies the federal, state and California Native Plant Society listing status,were reviewed to identify historical sightings of rare, threatened, or endangered plants a t
• the Site. No species other than those mentioned above were identified in the reports withrespect to the Site .
No adverse effect to native and non-native plant life will result from implementation ofthis project. Measures will be taken to minimize impact to rare and sensitive plantspecies as mentioned above and terrestrial plant species and the ecological communitiesin which they reside . Plant species listed as protected or identified for specialmanagement in the Fish and Game Code, the Public Resources Code, the Water Code orregulations adopted thereunder do not occur at the site and will not be impacted by theIM. Marine plant species and the ecological communities in which they reside do notoccur at the FSDF and will not be impacted by the IM .
Ref: Natural Diversi Data Base , Special Plants , Californ ia Department of Fishand Game(April 29, 1998) .
California Department of Fish and Game, Personal Conversation withMary Meyer (September 22, 1998) .
Biological Conditions Report, Santa Susana Field Laboratory, VenturaCognly, California, Ogden Environmental and Energy Services, (June1997) .
Revised by DTSC, PEAS 7/13/99
20
• Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facilily, Santa Susana Field Laboratory , ICF KaiserEngineers, Inc. (June 18, 1999) .
Memorandum : Sensitive/Rare Plant Protection During FSDF InterimMeasures , Michael Sullivan, Boeing North American, Inc . (September 15,1998) .
Padre Associates letter to IT Corporation and attachments, (May 14, 1999) .
0
Findings :Potentially
0 O O O
.Revised by DTSC, PEAS 7/13/99
21
•
•
5 . Animal Life (Workbook ; page 22)
Description ofEnvironmental Setting:
The FSDF began operations in the late 1950s and ceased operations in 1977 . The FSDFis developed and animal life was displaced long ago . No rare, threatened, or endangered(RTE) animal species were observed at the FSDF or the drainages . However, examplesof the RTE animal species that have been observed or have a potential to occur at otherareas of the SSFL are listed below :
species of special concern :
protected species :
special animal :
sensitive species :
harvest species :
San Diego black-tailed jackrabbit, coast patch-nosed snake,
American badger, San Diego horned lizard, San Diego
desert wood rat, loggerhead shrike, rufous-crowned
sparrow, sharp-shinned hawk, Cooper's hawk
coastal rosy boa, golden eagle , ringtail
two-striped garter snake, great blue heron
birds of prey (raptors), turkey vulture
mule deer, bobcat, mountain lio n
Ref: Biological Conditions Report, Santa Susana Field Laboratory, Ventura County,California, Ogden Environmental and Energy Services, (June 1997) .
Natural Diversity Data Base, Special Animals , California Department of Fish andGame, (April 29,1998) .
•
Analysis pfPotential Impacts :
The project involves removal of approximately 3,240 cubic yards of earth from five areaswithin the FSDF . No rare, threatened, or endangered (RTE) animal species wereobserved at the FSDF or the drainages and therefore, the project will not affect RTEanimal species. The habitat for these animal species are not located in the planned areasof excavation. Therefore, the project will not impact an imal species of concern or theirhabitat, animal species listed as protected or identified for special management in the Fishand Game Code, the Public Resources Code, the Water Code or regulations adoptedthereunder, or animal species and the ecological communities in which they reside whichare subject to the jurisdiction of the DFG . The FSDF ponds and western area will berevegetated with native plant species after completion of the IM and may create habitatfor animal species .
Revised by DTSC, PEAS 7/13/99
22
HDMSP00028238
•
The California Department of Fish and Game Natural Diversity Data B ase SpecialAnimal list, which identifies the federal, state and California Special Animal listingstatus , were reviewed to identify historical sightings of rare, threatened , or endangeredanimals at the Site . None were identified in the reports with respect to the SSFL .Historical sightings of the San Diego Horned Lizard were 2 .5 miles southwest and onemile west of Woodland Hills .
Listed threatened or endangered animals and the habitat in which they reside are notlocated in the proposed project area and will not be impacted . Animals listed as protectedor identified for special management in the Fish and Game Code, the Public ResourcesCode, the Water Code , or regulations adopted thereunder do not occur at the FSDF andwill not be impacted . Marine and terrestrial animal species subject to the jurisdiction ofthe DFG and the ecological communities in which they reside do not occur at the FSDFand will not be impacted .
Ref: Natural Diversity Data Base, Special Animals , California Department of Fish andGame (April 29 , 1998) .
Biological Conditions Report, Santa Susana Field Laboratory, VenturaCounly, California , Ogden Environmental and Energy Services, (June1997) .
•Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facilily, Santa Susana Field Laboratory , ICF KaiserEngineers , Inc. (June 18 , 1999) .
Findings:
Revised by DTSC, PEAS 7113/99
PotentiallyO 0 O O
23
HDMSP00028239
0
-------------------------------------------------------------------------------------------------------------
6. Land Use (Workbook ; page 24)
Description Environmental Setting :
Land use and development are managed by the County of Ventura . The site is currentlyzoned R-A-5Ac, rural agricultural , 5-acre minimum lot size . Boeing No rth American,Inc. holds conditional use permit 248 for indust rial land use. The lands to the no rth andwest have been designated by Ventura County as "open lands" under the county openspace plan which is zoned as R-A-5Ac , rural agricultural , 5-acre minimum lot size andA-E, agricultural exclusive . To the south of SSFL , the land is zoned R-E-1Ac, ruralexclusive one acre .
Ref: Correspondence from Michael Sullivan, Boeing North American, Inc .(July 7, 1998) .
Groundwater Remediation Operations Plan , Santa Susana FieldLaboratory (May 25, 1990, revised April 21, 1998) '
0
Analysis Potential Impacts :
The proposed excavation will not affect the present or planned land use of the site. TheSSFL will continue to operate as a rocket engine testing facility . Excavated areas will befilled with clean materials then revegetated . Although the removal of contaminated soilsmay enhance the site's potential for conveyance and future reuse, site cleanup will notchange the pattern, scale or character of the neighborhood .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facili Santa Susana Field Laboratory, ICF KaiserEngineers , Inc . (June 18, 1999) .
Findings:Potentially
U 0 O O
7. Natural Resources (Workbook; page 25 )
Revised by DISC, PEAS 7/13/99
24
HDMSP00028240
•
•
Description Environmental Settin :
The Site is located in the Simi Hills of Ventura County . The area is rural and dominatedby massive sandstone beds . Commercial and residential l and uses surround the site .
Natural resources in southe astern Ventura County include a 1,904 acre area located acrossthe northern portion of Simi Valley and extending easterly and westerly of the GillibrandQuarry site, and a 371 acre area located in Runkle Canyon, northeasterly from andincluding the Southern Pacific Milling Company Quarry which have been designated asareas of regionally significant construction aggregate resources . The area adjacent to theGillibrand Quarry continues its mining operations . Access to this area is maintained viathe future extension of Bennett Road north to Tripas Canyon . Located north of SimiValley are small discrete oil and gas fields with production wells .
There are no known natural resources under the Site . Utility conveyance systems provideelectricity and potable water to the site and surrounding development .
Ref: City of Simi Valley General Plan , City of Simi Valley, Pp . 4.2, 4 .3(Adopted October 18, 1988)
Analysis gfPotential Impacts :
The excavation and transportation of soil will not involve the increased use of or hinderthe extraction of necessary natural resources . Non-renewable energy sources will not bedepleted as a result of project implementation . No treatment activities or exp ansion offacility operations are proposed for the FSDF .
Ref: Final Draft Interim Me asures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory , ICF KaiserEngineers , Inc. (June 18, 1999) .
Findings :Potentially
0 0 0 a
-------------------------------------------------------------------------------------------------------------
8 . Risk of Upset (Workbook; page 26)
Description ofEnvironmental Settin :
Revised by DTSC, PEAS 7/13/99
25
HDMSP00028241
•The IM involves excavation of contaminated soil, transportation of the soil to an off-sitedisposal facility, and placement of fill materials in some of the excavated areas . Theexcavation and the backfill activities have the potential to generate dust . Thetransportation activities on-site occur on Boeing property in Ventura County, on publicroads under the jurisdiction of the City of Los Angeles (from the SSFL gate to the 118freeway), and on California Highways 118, 405, and 5 under the jurisdiction of theCalifornia Highway Patrol to its final destination in Kettleman City .
The County Office of Emergency Preparedness and the California Office of EmergencyServices have the responsibility of coordinating personnel, equipment, resources andfacilities in case of an emergency . A fire station is located on-site and in Santa SusanaKnolls, approximately two miles to the north of the SSFL . The Simi Valley and LosAngeles Police Departments and the Ventura County and Los Angeles County SheriffDepartments respond to emergencies .
Ref: City of Simi Valley General Pl an , City of Simi Valley (Adopted October18, 1988)
Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facilit Santa Susana Field Laboratory , ICF KaiserEngineers, Inc . (June 18, 1999) .
•
Analysis Potential Impacts :
The excavation and backfill activities have the potential to generate dust . However,measures will be taken to suppress dust generation by wetting the soil with water beforeexcavation and during loading of soil into the bins, and complying, at a minimum, withthe Ventura County Air Pollution Control District's Rule 50 (limits the discharge of aircontaminants based on opacity), Rule 51 (limits the discharge of air contaminants posinga nuisance to the public), and Rule 74.29 (soil decontamination operations for gasoline,diesel and jet fuel) . Moreover, monitoring with field instruments will be performed for :dust using the miniRam ; volatile organic compounds using a flame-ionization detector ora photo-ionization detector ; and mercury using a Jerome Instruments monitor . The dustsuppression measures being taken during the excavation and backfill activities and thedistance of approximately one mile from the FSDF to the nearest resident will not resultin impacts from fugitive dust .
Excavation activities have the potential to be interrupted by a sudden rain storm . Thecontrol measure that will be taken to avoid migration of contaminated soil down thedrainage channels and off-site is diversion of the surface water flow away from channelsA and B to a drainage channel to the east. The weirs in channels A and B will be abackup for trapping any sediment that does migrate down the channels . The sedimenttrapped by the weirs is removed when the height of the sediments are one foot below thetop of the weir . The control measure of diverting surface flow away from channels A an d
Revised by DTSC, PEAS 7/13/99
26
HDMSP00028242
• B along with the trapping of sediment behind the weirs will not result in impacts fromexcavation activities .
The transportation of contaminated soil off-site has the potential to cause a risk of upset ifthe truck is involved in an accident and the waste is released to the ground surface .Measures that will be taken during transport of contaminated soil off-site to the disposalfacility, thereby reducing the probability of an accident and subsequent spill releaseinclude :
• terminating transport during inclement weather conditions when visibilityis reduced as a result of fog, heavy rain, or snow, and dangerous roadconditions exist as a result of ice or sleet ;
• using routes that are safe for large trucks to travel on such that sharp turnsand steep grades are avoided ;
• monitoring the number of trucks that can be on the local roads at any onetime. One traffic coordinator will be stationed on Topanga CanyonBoulevard at the entrance to the 118 freeway and another at the FSDFloading area. The coordinator will space the trucks arriving and leavingthe site so as to avoid congestion on the local roads .
0
•
Ref: Ventura Coun Air Pollution Control District Rules 50, 51, and 74.29
Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facilily, Santa Susana Field Laboratory , ICF KaiserEngineers, Inc. (June 18, 1999) .
Findings :
PotentiallyO O O
Revised by DTSC, PEAS 7/13/99
27
0
HDMSP00028243
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9. Transportation /Circulation (Workbook; page 29)-------------------------------------------------------------------------------------------------------------
Description Environmental Settin :
The project will remove approximately 3,240 cu . yards of soil contaminated withmercury, PCB and dioxin from the FSDF upper pond, area to the west of the pond, andthree drainage channels A, B, and C, then backfill all areas except Channels A and C anda portion of Channel B with clean imported soil . The contaminated soil will betransported from the FSDF to Chemical Waste Management in Kettleman Hills,California. The FSDF is located at the west end of the SSFL . A main east-west trendingroad leads from the FSDF to the SSFL entrance gate (Figure 4) . Local roads lead fromthe SSFL to the 118 Freeway, the primary route of transport will include WoolseyCanyon, Valley Circle, Roscoe Boulevard, and Topanga Canyon . The maintransportation artery in Simi Hills is Topanga Canyon, a north-south road with threetraffic lanes in each direction which provides access to the 118 and 101 Freeways . Thetrucks will travel east on the 118 Freeway, north on the San Diego Freeway 405, north onInterstate 5, and south on Highway 41 to the disposal facility (Figure 5) . If it is necessaryto import back-fill material, the same route from the 118 Freeway to the FSDF will beused to import clean soil for use as backfill at the FSDF .
The City of Los Angeles monitors peak traffic hours and maintains traffic counts for• intersections within the city . The peak traffic hours for the intersections along the route
from the FSDF to the 118 Freeway are 7 :00 a.m. to 9 : 00 a.m . and 4 :00 p.m. to 7 : 00 p.m .Traffic counts during peak hours on Valley Circle Boulevard at Lake Manor (1/97) andRoscoe at Valley Circle Boulevard (11/93) range from 4,360 to 10 ,354 vehicles . Peakhour traffic counts north on Top anga Canyon at Roscoe ( 1/96), Plummer (9/93) andDevonshire (9/97) range from 34,852 to 45,508 .
0
Comparison of the volume of traffic on a road to its capacity determines theLevel-of-Service or the time delay per vehicle . Level-of-Service standards ("A" through"F") are set for intersections, with "A" being very low delay and "F" being very highdelay or volume of traffic exceeds the capacity of the intersection. Along the route, theLevel-of-Service standards for the intersections on City of Los Angeles Streets to the 118Freeway are designated as "E" and the 118 Freeway is designated as "F" . The currentLevel-of-Service on city streets range from "B" to "E" and on the 118 Freeway is at "F" .
Boeing North American, Inc . proposes to transport the contaminated soil in closed-top
bins and 18-wheel end-dump trucks covered with a tarp . The closed-top roll off bins and
the dump trucks have a capacity of 20 to 25 tons. It is expected that an average of 18trucks per day, over a 10 day duration, will be necessary to remove the 3,240 cu . yards of
contaminated soil. Although not anticipated during transportation of the contaminated
soil off-site, a maximum of 39 trucks per day may enter and leave the site five days a
Revised by DTSC, PEAS 7/13/99
28
HDMSP00028244
• week, between the non-peak hours of 9:00 a.m. and 4 :00 p .m. This is based on amaximum 6 trucks per hour departing the site between the hours of 9 :00 a .m. and 3 :30p.m .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, SantaSusana Field Laboratory , ICF KaiserEngineers, Inc. (June 18, 1999) .
1997 Congestion Management Pl an for Los And County, Los AngelesCounty Metropolitan Transit Authority (Adopted November 1997) .
Analysis (Potential Impacts :
For purposes of transportation impact analysis, a worst-case scenario was used. Impactswere determined for transporting contaminated soil off-site and importing clean fill to thesite .
The Interim Measures Workplan will not involve, nor result in a change of transportationor circulation. Lane closure is not necessary during transportation of waste off-site .However, traffic control measures will be implemented to maintain a ten minute intervalbetween trucks leaving the SSFL to minimize congestion on local roads . Interstate 118which is approximately 10 miles northeast of the FSDF will be the primary route fortransportation of waste off-site . Trucks will proceed on local roads to Interstate 118 asfollows : eastbound on Woolsey Canyon Road, a two lane road which leads from theSSFL entrance gate down the hill ; south on Valley Circle, also a two lane road ; east onRoscoe Boulevard, a four lane road with two lanes in each direction ; and north onTopanga Canyon, a six lane road with three lanes in each direction which intersects withInterstate 118. This route was selected because it avoids difficult terrain (steep grades)and sharp turns, and is the widest available artery, making it the safest route from theFSDF to the off-site disposal facility -- Chemical Waste Management, 35351 Old SkylineRoad, Kettleman Hills Facility, Kettleman City, California 93239 . Moreover, utilizingthis route will cause the least inconvenience to nearby residents. The artery is accessibleto emergency service organizations and traffic control agencies. No impacts to regionalor local circulation are anticipated as a result of the project .
The City of Los Angeles recommended a route which proceeds east on Woolsey Canyon,north on Valley Circle Boulevard , east on Lake M anor, east on Plummer and then northon Topanga Canyon Boulevard to the 118 Freeway. This recommendation was based onthe low density population and shorter distance from the FSDF to the 118 Freeway .However , selection of this route did not take into consideration safety . Therefore, due tosafety considerations , such as steep grades and sharp turns , this route was not selectedand the proposed route previously mentioned remains the primary route of transport .
• Revised by DTSC, PEAS 7/13/99
29
•
•
Parking for construction personnel will be located on the SSFL site . No impacts toexisting parking or demand for new parking will result from the project .
Drivers will exercise extreme caution on the road and will adhere to all traffic laws,especially posted speed limits . Measures to reduce the risk of upset will be to ceasetransportation operations when conditions are such that the roads are wet/icy, there ispoor visibility, or high wind speeds. Hence, no increases in traffic hazards to motorvehicles or pedestrians will result from this project .
The amount of contaminated soil to be transported off-site for disposal is approximately4,860 tons (3,240 cu. yd.) . The contaminated soil contains concentrations of mercury,PCB, and dibenzo-dioxin that pose a risk to human health and the environment if left inplace. Approximately 150 tons (100 cu. yd.) of the hazardous waste (mercuryconcentrations greater than 20 mg/kg) and 4,710 tons (3,140 cu. yd.) of non-hazardouswaste will be transported off-site in closed-top roll-off bins or 18-wheel end dump truckscovered with a tarp . It is estimated that transportation of contaminated soil excavatedfrom the FSDF will be performed in twenty-one (21) days . The trucks are scheduled tohaul the contaminated soil five days per week between the hours of 9 :00 a.m. and 3 :30p.m. No impacts to transportation or circulation will result from implementation of theproject .
Discussions with staff of the City of Los Angeles Department of Transportation indicatethe proposed project, regardless of whether clean fill is imported or fill obtained from anon-site source, will have no appreciable impact on the Level of Service (LOS )designation for the proposed transportation route if a minimum 15 minute intervalbetween trucks entering and leaving the site during the hours of 7 to 9 a .m. and 4 to 7p.m. is implemented . This requirement has been incorporated as a part of theTransportation Plan for the IMW .
Ref: IT Corporation letter to Mr . Raymond Wellbaum, West Valley District, City ofLos Angeles Department of Transportation. (June 17, 1999)
Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility. Santa Susana Field Laboratory , ICF KaiserEngineers, Inc . (June 18, 1999) .
City of Los Angeles : Valley Transportation an d Planning, Personalconversation with Vahan Pezeshkian (8/26/98) .
1997 Congestion Management Program for Los Angeles County, LosAngeles County Metropolitan Transportation Authority (AdoptedNovember 1997) .
. Revised by DTSC . PEAS 7/ 1 3/99
30
Finding
•
. Revised by DISC, PEAS 7/13/99
PotentiallyPotentially Significant Less ThanSignificant Unless Significant NoImpact Mitigated Impact Impac tO O 0 O
31
•
•
10. Public Services (Workbook; page 31)
Description gfEnvironmental Setting:
The Site is located in Simi Hills at the e as t end of Ventura County adjacent to the LosAngeles County line . Services are provided by Ventura County Fire Department which islocated in Santa Susana Knolls, approximately two miles north of SSFL, and the VenturaCounty Sheriff Department . The fire station located on site is owned and operated byBoeing North American, Inc. Nearby services are provided by the Simi Valley PoliceDepartment and the Los Angeles County Sheriff Department .
Schools are not located within a one mile radius of the FSDF, with the exception of theBrandeis-Bardin Institute which is located directly to the north of the FSDF at the SSFLproperty line . The Brandeis-Bardin Institute is a privately owned facility that provideseducational programs, seminars, and conferences to people of all ages .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory, ICF KaiserEngineers , Inc. (June 18 , 1999) .
Correspondence from Boeing North American, Inc . staff (July 7, 1998) .
Analysis Potential Impacts :
The IM will involve excavation and transportation of soils that are not combustible .Therefore, no increased need for fire protection will result from implementation of thisproject . The SSFL is a secured facility with guards present 24 hours a day and one gatewhere persons entering must sign in . Because of this, the facility is not susceptible totheft or sabotage, thereby not increasing the demand on police protection .
As described in the FSDF IM Workplan, activities are proposed to occur within aconfined area over a three month period, thus causing minimal disruption to thecommunity . The excavation of soil from the FSDF and drainage channels will removethe risk to human health from contaminants that would otherwise migrate down thedrainage channels towards the Brandeis-Bardin Institute . The project will not altercurrent levels of governmental services or public facilities including police and fireprotection, schools, parks and recreational facilities, and roads .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility . Santa Susana Field Laboratory , ICF KaiserEngineers, Inc . (June 18 , 1999) .
Revised by DTSC, PEAS 7/13/99
32
HDMSP00028248
• FindingPotentially
Potentially Significant Less ThanSignificant Unless Significant No0 O O D
-------------------------------------------------------------------------------------------------------------
. Revised by ATSC . PEAS 7113199
33
HDMSP00028249
-------------------------------------------------------------------------------------------------------------
•
11 . Energy (Workbook ; page 32)-------------------------------------------------------------------------------------------------------------
Description Q[Environmental Setting
The SSFL uses substantial amounts of energy and fuel for its operations of engine testingand research .
Ref: RCRA Facility Investigation Workplan Addendum, Santa Susana FieldLaboratory , Ventura County, Ogden Environmental and Energy Services(August 1996) .
Analysis Q[Potential Impacts :
The IM will not involve, nor result in permanent change of the existing demand forenergy. The contaminated soil will be transported off-site to a disposal facility certifiedto accept hazardous as well as non-hazardous waste . No new facilities will be developedas a result of this project. Use of fuel for transportation of waste off-site and importationof clean soil for use as backfill material is temporary, a total of approximately threemonths . After completion of the project, the demand for fuel will cease . While the fuelused is irretrievable, it is readily available . Therefore, the project's impact to fuel isglobally insignificant.
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory, ICF KaiserEngineers, Inc . (June 18, 1999) .
Findings
Revised by DTSC . PEAS 7/13/99
PotentiallyPotentially Significant Less ThanSignificant Unless Significant NoD O J 0
34
HDMSP00028250
•
•
12. Utilities (Workbook ; page 32)
Description pfEnvironmental Setting:
The site is located in Simi Hills . The Calleguas Water District is the water purveyor tothe SSFL and nearby residents . Natural gas is used for heating of buildings at SSFL .
Ref: Correspondence from Michael Sulliv an, Boeing North American , Inc .(July 7, 1998) .
Analysis pfPotential Impacts:
The IM will not result in a need for new systems or substantial alterations to any utilities .The contaminated soil will be transported off-site to an authorized disposal facility .
Accordingly, municipal solid waste disposal, water, and natural gas use will not increaseas a result of this project .
Ref: Final Draft Interim Measures Workman for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory , ICF KaiserEngineers, Inc. (June 18, 1999) .
Findings :
Revised by DTSC. PEAS 7/ 1 3/99
PotentiallyPotentially Significant Less ThanSignificant Unless Significant Noa O O th7
35
HDMSP00028251
• 13. Noise (Workbook; page 32 )
Description gfEnvironmental Setting:
The site is located in Simi Hills . The predominant noise sources at the SSFL are fromrocket engine tests and motor vehicle traffic . The predominant noise sources that willoccur from the IM activities are from motor vehicles during transport of contaminatedsoil off-site . Trucks will proceed on local roads in the City of Los Angeles to Interstate118 as follows: eastbound on Woolsey Canyon Road, south on Valley Circle, east onRoscoe Boulevard, and north on Topanga Canyon to Interstate 118 . Interstate 118 whichis approximately 10 miles northeast of the FSDF will be the primary route for off-sitetransportation of waste .
The City of Los Angeles prohibits noise from construction and excavation work betweenthe hours of 9 :00 P.M. and 7:00 A.M. of the following week-day, before 8 :00 A.M. orafter 6 : 00 P.M . on any Saturday or national holiday , and any time on Sunday . For trucktraffic noise, California Vehicle Code limits the noise from heavy duty trucks to 86 dbAat speeds of 35 mph or less and 90 dbA at speeds greater than 35 mph, measured 50 feetfrom the center of the lane of travel .
• Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility . Santa Susana Field Laboratory , ICF KaiserEngineers , Inc. (June 18, 1999) .
City of Los Angeles Municipal Code. Chapter IV, Article I, Section 41 .40Noise Due To Construction , Excavation Work - When Prohibited .
California Vehicle Code , Section 23130 Vehicle Noise Limits .
Analysis QfPotential Impacts :
The noise levels from the excavator and trucks during implementation of this project willbe limited to Monday through Friday during the hours of 7 :00 a .m. to 7 :00 p.m. (whenthe last truck will leave the site) . No work will occur on Saturday or Sunday. Theduration of the project is three months . On-site noise will be generated from the use of abackhoe for soil excavation . This type of equipment can generate 72 to 92 dbA at aboutfifty feet from the source . The FSDF is approximately one mile away from the nearestresidential area to the south, east, and north . Work will be performed in compliance withthe State and local noise regulations . No impacts from on-site mobile sources will resultfrom project implementation .
Revised by DTSC, PEAS 7/13/99
36
HDMSP00028252
•
•
The FSDF on-site workers will receive the greatest impact from noise generated by heavyequipment operation . Noise levels will be measured with field instrumentation during theIM activities. When noise levels exceed the Cal-OSHA allowable levels for workersafety, these impacts will be mitigated by requiring use of ear protection . The FSDF islocated on the western end of the SSFL, away from buildings that employ other SSFLemployees . The project will not impact other SSFL personnel .
Off-site transportation will generate noise on arterials and Interstate 118 . Project controlmeasures will be implemented to limit project related noise impacts on sensitivereceptors . At a minimum , a ten minute interval between trucks leaving the SSFL will bemaintained to minimize noise and traffic congestion. Days and times of transport willalso be limited so that noise generation does not extend beyond that allowed by State andlocal regulation. The transportation contractor will use 1993 and newer model yeartrucks which were designed to meet the noise standards set by the California Departmentof Motor Vehicles. The noise levels from these trucks have been monitored during othertransportation projects without exceeding the noise st andards . During the implementationof the IM , truck noise levels will be monitored periodically to ensure that the noisestandards are not being exceeded . In the event that a truck exceeds the noise level, it willbe taken out of service . With implementation of these control measures, no impact willresult from this project .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory , ICF KaiserEngineers , Inc. (June 18, 1999) .
City of Simi Valley General Plan, City of Simi Valley P 2 .9 (AdoptedOctober 18, 1988) .
Correspondence from Michael Sullivan, Boeing North American, Inc .(September 15, 1998) .
Findings :
Revised by DTSC, PEAS 7/13/99
PotentiallyPotentially Significant Less ThanSignificant Unless Significant Noa O 0 0
37
HDMSP00028253
-------------------------------------------------------------------------------------------------------------
14 . Public Health and Safety (Workbook; page 34)
Description g[Environmental Settin :
The protection of public health and safety was considered during preparation of the IMWorkplan . It is not anticipated that public health and safety will be end angered byimplementation of the project . However, two worst case scenarios for on-site and off-sitepublic health and safety are presented here and analyzed below to show the measurestaken to minimize risk. First , the on-site personnel could be exposed to the mercu ryvapors , PCB, and dioxin during excavation and/or loading activities . The safety of theon-site personnel could also be jeopardized by the heavy equipment used during the IMimplementation . Second, off-site , an accident could occur on a heavily traveled arteryduring transportation of contaminated soil to the disposal facility resulting in thehazardous waste spilling out of the closed -top bin . The feasible health hazards from thespilled load would be inhalation of mercury vapors and particulate matter . The safetyrisks that could potentially impact the surrounding community are vehicle accidents .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the Former SodiumDisposal Facility, Santa Susana Field Laboratory , ICF Kaiser Engineers, Inc .(June 18, 1999) .
• Analysis pfPotential Impacts :
•
Public health and safety will be protected during implementation of the project. Fieldinstruments to measure dust, VOCs, and mercury vapor levels will be used duringexcavation and loading of contaminated soil as well as dust suppression methods . Thepersonnel performing the excavation will be protected from inhalation hazards byremaining in an enclosed-cabin loader equipped with an air filter to minimize exposure toairborne particulate matter . To avoid unnecessary exposure to fugitive dust emissionsand physical risks associated with heavy equipment , on-site personnel will not be allowednear the loading area . Truck drivers arriving at the FSDF with an empty truck will not beallowed to exit the truck or enter the loading area when loading of a truck is underway .The driver will park the truck at the loading area then exit the truck and stand upwindduring the loading . After loading has been completed, the trucks will undergodecontamination , by brushing o ff any soil remaining on the tires and outside of the truck .It is not anticipated that the soil on the trucks will be wet but if this occurs, a wet
decontamination of the trucks will be performed . Excavation and loading ofcontaminated soil when implementing these measures should not pose a significant riskto public health or the workers through the known exposure pathways.
For the truck accident scenario , measures to reduce probability of occurrence have beentaken .
Revised by DTSC, PEAS 7/13/99
38
HDMSP00028254
• • All contaminated soil will be transported in a closed-top bin or a tarpcovered end-dump truck.
• Selection of the transportation route was based on safety . The primaryroute is wider than other local roads that lead to the 118 Freeway, does nothave the difficult terrain (steep grades and sharp turns) that other localroads have, and is accessible to emergency service organizations .
• Transportation will not occur during inclement weather conditions whenvisibility is reduced (fog or heavy rain), or when the potential for roadhazards are at their greatest (icy roads) .
• The number of trucks that can be on the local roads at any one time will bemonitored . One traffic coordinator will be stationed on Topanga CanyonBoulevard at the entrance to the 118 freeway and another at the FSDFloading area. The coordinator will space the trucks arriving and leavingthe site so as to avoid congestion on the local roads . The Level-of-Serviceat intersections and the 118 Freeway will not be lowered .
• All traffic laws will be strictly adhered to .
•
•
• All emergency service organizations will be notified of the days and timesof transport of contaminated waste, the primary and alternate routes, thequantities of waste, concentrations and chemical composition. This willallow for shorter response times if an accident does occur .
An accident could still occur with these measures in place, however, to minimize risk topublic health and safety, truck drivers will be trained and carry equipment to implementthe Contingency Plan in the event of an emergency situation. Each driver will have awireless communication device, traffic cones, signs, caution tape, personal protectiveequipment, and cleanup tools . The driver will immediately isolate the spill area byplacing traffic cones around the spill, calling local emergency response authorities to helpsecure the spill area and blocking access to unauthorized persons, calling thetransportation coordinator to dispatch necessary equipment such as a loader and an emptyend-dump truck or truck with closed-top bin and emergency crew to clean up the spill .The residual will be cleaned up with a broom and vacuum cleaner . Based on themethods and protocol established for project implementation, no significant short- orlong-term public health risks are anticipated .
The concentrations of PCB and dioxin in the soil at the FSDF pose a risk to human healthand the environment if not remediated . The concentrations are above the acceptable risklevels for the residential scenario and will continue to migrate down the drainagechannels towards the Brandeis-Bardin Institute if they remain in place . The removal ofthe soil down to bedrock will remove this potential risk to human health . _
Revised by DTSC, PEAS 7/13/99
39
HDMSP00028255
• Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the Former SodiumDisposal Facility, Santa Susana Field Laboratory , ICF Kaiser Engineers, Inc .(June 18, 1999) .
Findins:
•
PotentiallyO 0 O L 7
• Revised by DTSC, PEAS 7/13199
40
-------------------------------------------------------------------------------------------------------------
• 15. Aesthetics (Workbook; page 38)-------------------------------------------------------------------------------------------------------------
Description Q[Environmental Setting:
The SSFL has sweeping views of tranquil hills surrounding it . These hills are visible tothe public residing in and around Simi Hills and Simi Valley, and traveling on majorhighway arterials . The City of Simi Valley has established policies to preserve thenatural topographic features of the hills, enhance views of the hillsides from the valleyfloor as well as the viewshed from the hills, and prevent significant deterioration in localair quality .
Ref: ~jty of Simi Valley General Plan, P . 3 .11 (Adopted October 18, 1988)
Analysis Q[Potential Impacts :
The proposed project involves excavation of the soil deposited on the massive sandstonebeds of the Chatsworth Formation. The topography of the massive sandstone beds willremain unchanged . In areas where contamination stained bedrock is observed at thecontact between the soil and the sandstone, approximately two inches of the weatheredbedrock will be scraped off. The FSDF will be restored to its pre-operational conditionafter completion of the IM activities . The FSDF ponds, western area, and a portion o f
• channel B will be backfilled with clean soil and revegetated with native plant species. Noimpacts to scenic vistas or view corridors are expected with implementation of theproject .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the Former SodiumDisposal Facility, Santa Susana Field Laboratory , ICF Kaiser Engineers, Inc .(June 18, 1999) .
•
Findings:Potentially
O O O U
Revised by DTSC, PEAS 7/ 1 3/99
41
HDMSP00028257
•16 . Cultural/Paleontological Resources (Workbook ; page 39)
Description Q[Environmental Setting :
The Burro Flats Pictograph Cave Paintings are included on the National Register ofHistoric Places . Chumash Indian petroglyphs have been observed by the Boeing NorthAmerican, Inc . staff in the SSFL "buffer zone" .
Ref: RCRA Facility Investigation Workplan Addendum, Santa Susana FieldLaboratory, Ventura County, Ogden Environmental and Energy Services(August 1996) .
City of Simi Valley General Plan, P 4.3 (Adopted October 18, 1988)
•
Analysis pfPotential Impacts :
Cultural or paleontological resources are not located in the areas of proposed excavation,and backfill nor in the area proposed for the on-site borrow pit. Therefore,cultural/paleontological resources will not be impacted by the IM activities .
Ref: Final Draft Inte rim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory, ICF KaiserEngineers, Inc. (June 18, 1999) .
Draft Cultural Resource Assessment and Report on Archival Research , SurfaceReconnaissance , and Limited Subsurface Evaluation at Rocketdyne SantaSusanna Field Laboratory , Ventura County, Californ ia, Ancient Enterprises, (June16, 1999)
Findings :Potentially
O O O O
• Revised by DTSC, PEAS 7/13/99
42
•
•
17. Cumulative Effects (Workbook ; page 42)
Description Q(Environmental Setting:
Within this Initial Study, the analysis of potential impacts has shown that an impact onthe environment will occur for : Air - potentially significant unless mitigated ; Surface andGroundwater - less than significant impact ; Plant Life- less than significant impact ; andTransportation/Circulation - less than significant impact . The other elements will not beimpacted by the project .
Ref: Elements 1 through 16 of the Initial Study for the Interim Measures for theFormer Sodium Disposal Facility, Santa Susana Field Laboratory .
Analysis gfPotential Impacts :
Control measures will be implemented to minimize the impacts to air, surface andgroundwater, plant life, and transportation/circulation to less than significant . For air, thegeneration of dust will be controlled by applying water before excavation activities andduring loading of the contaminated soil into the closed-top bins or end-dump trucks .Field instruments will be used to monitor the dust levels with the miniRam, volatileorganic compounds with an organic vapor analyzer, and mercury vapors with the JeromeInstrument monitor. To reduce impacts to air, transportation of contaminated soil off-sitewill be limited to non-peak hours . The construction period will be lengthened tominimize the number of vehicles and equipment operating at the same time, andconstruction equipment will be maintained in good condition . For surface water, thediversion of water away from drainage channel B is temporary and flow will be returnedto existing drainage patterns after IM implementation . Impacts to plant life will not occuras the Valley Oak trees will be fenced off so that soil within their drip line is notdisturbed and the Santa Susana Tarplant will be flagged so that workers will not step onor otherwise damage these plants when entering the drainage channels or removingcontaminated soil . If fill from an off-site borrow source is necessary, impacts totransportation will be controlled by observing a minimum 15 minute interval betweentrucks leaving the site during the hours of 7 :00 a.m. to 9:00 p.m. and 4 :00 p .m. to 7:00p.m., so as not to lower the Level-of-Service standards . The City of Los Angeles hasstated that based on the number of truck trips per day, the project is not large enough tocause traffic impacts or require a traffic study . Furthermore, heavy equipment will berestricted to access points where the Santa Susana Tarplant cannot be damaged . Theproject is an interim measure and may lead to additional work when the final remedy isselected. However, the interim measure is consistent with the final remedy for the site .The project will not impact population, housing or recreation nor will it have adverseeffects on air, water, habitats natural resources or utilities .
. Revised by DTSC, PEAS 7/13 199
43
•
•
At this time, DTSC is not aware of other ongoing projects in the area except for theRCRA Facility Investigation (RFI) at SSFL . The site is currently being investigated todetermine the lateral and vertical extent of contamination as a result of past operations.The majority of the soil sampling has been completed and an evaluation of the data willdetermine if additional work is needed for site characterization . The extent of anyremoval or remedial activities and associated impacts are not known and are toospeculative for analysis at this time . DTSC will comply with CEQA for any actionsproposed as a result of the RFI .
Ref: Final Draft Interim Measures Workplan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory, ICF KaiserEngineers, Inc. (June 18, 1999) .
Findings:Potentially
O O O 0
• Revised by DISC, PEAS 7/13/99
44
•
•
------------------------------------------------------------------------------------------------------------
18. Population/Housing/Recreation (Workbook; page 43 )------------------------------------------------------------------------------------------------------------
Description ofEnvironmental Setting:
The SSFL employs approximately 700 people, with no residents located on-site . Theclosest residents to the FSDF are approximately one mile away, in Bell Canyon to thesouth and on Woolsey Canyon to the east of the SSFL entrance gate . The City of SimiValley is more than one mile to the north of the FSDF . The Sage Ranch, a publicrecreation park owned by the Santa Monica Conservancy is directly to the north of theSSFL .
Projected populations for areas near the site are listed below .
Area Population
Simi Valley 100,218 (1990)
Chatsworth 61,900 (1977 )
Woodland Hills 84,000 (1976)
Ref: Correspondence from Michael Sullivan, Boeing North American, Inc .(July 7, 1998) .
~fl of Simi Valley General Plan, P 5 .14 (Adopted October 18, 1988 )
Analysis Potential Impacts :
The project will take three months to complete and will not affect existing housing, orcreate a demand for additional housing . The project will not displace any residents andwill not alter the location, distribution, density or growth rate of the human population .The transport of waste off-site will not occur in recreational areas or require closure ofroads and therefore, will not impact the quality or quantity of existing recreationalopportunities .
Ref: Final Draft Interim Measures Workylan for Soil Cleanup at the FormerSodium Disposal Facility, Santa Susana Field Laboratory , ICF KaiserEngineers, Inc. (June 18, 1999) .
Revised by DISC, PEAS 7/13/99
45
HDMSP00028261
Findings :
Revised by DTSC, PEAS 7/13/99
PotentiallyO 0 O
46
HDMSP00028262
•19. Mandatory Findings of Significance (Workbook ; page 44)
Potentially
Potentially Significant Less Than
Signfftcant Unless Significant No
Impact Mitigated Impact Impact
•
a) Does the project have the potential to degrade O L7 O O
the quality of the environment, substantially reduc e
the habitat of a fish or wildlife species, cause afish or wildlife population to drop below self-sustaining
levels, threaten to eliminate a plant or animal
community, reduce the number or restrict the
range of a rare or endangered plant or animal oreliminate important examples of the major
periods of California history or prehistory?
b) Does the project have the potential to achieve O O O O
short - term , to the disadvantage of long-term ,
environmental goals?
c) Does the project have impacts that are O O O O
individually limited, but cumulatively considerable ?
("Cumulatively considerable" means that the
incremental effects of a project are considerable
when viewed in connection with the effects of past
projects, the effects of other current projects, andthe effects of probable future projects )
d) Does the project have environmental effects 0 O O O
which will cause substantial adverse effects o n
human beings , either directly or indirectly?
• Revised by DISC, PEAS 7/13/99
47
•
•
V. DETERMINATION OF DE MINIMIS
On the basis of this Initial Study :
O I find that there is no evidence before DTSC that the proposed project will have a potential for an
adverse effect on wildlife resources or the habitat upon which the wildlife depend . A NEGATIVE
DECLARATION with a DE MINIMIS IMPACT FINDING will be prepared .
VI. DETERMINATION OF SIGNIFICANT EFFECT
On the basis of this Initial Study :
O I find that the proposed project COULD NOT have a significant effect onthe environment . A NEGATIVE DECLARATION will be prepared .
/X" I find that although the proposed project COULD HAVE a significanteffect on the environment , mitigation measures have been added to theproject which would reduce these effects to less than significant levels . AMITIGATED NEGATIVE DECLARATION will be prepared.
O I find that the proposed project COULD HAVE a significant effect on theenvironment. An ENVIRONMENTAL IMPACT REPORT will beprepared .
Gerard Abrams Project ManagerName of Preparer Title
Signature of Preparer Date
. Revised by DTSC, PEAS 7/13/99
48
•
ATTACHMENT AINITIAL STUDY
REFERENCE LISTfor
Interim Measure for the Former Sodium Disposal Facilit y
1 . Annual Groundwater Monitoring Report, Santa Susana Field Laboratory, 1997 ,Groundwater Resources Consultants, Inc . (February 25, 1998) .
2 . Biological Conditions Report, Santa Susana Field Laboratory, Ventura County,California , Ogden Environmental and Energy Services, Inc . (June 1997) .
3 . Correspondence from Michael Sulliv an, Boeing North American, Inc .(July 7, 1998) .
4. California Department of Fish and Game, Natural Diversity Data Base,Special Plants (April 29, 1998) .
5 California Department of Fish and Game, Natural Diversity Data Base, SpecialAnimals (April 29, 1998) .
6. California Department of Fish and Game, personal conversation wit h• Mary Meyer (September 22, 1998) .
7 . California Vehicle Code, Section 23130 Vehicle Noise Limits .
8 . City of Simi Valley General Plan , City of Simi Valley (Adopted October 18,1988) .
9. ~jty of Los Angeles Municipal Code, Chapter IV, Article I, Section 41 .40Noise Due To Construction, Excavation Work - When Prohibited .
10. Conditional Use Permit - Environmental Cleanup of the Former Sodium DisposalFacility, General Notes, Boeing North American, inc ., Ventura County, California(September 8, 1992) .
11 . 1997 Congestion Management Program for Los Angeles County, LosAngeles County Metropolitan Transportation Authority (AdoptedNovember 1997) .
12 . Final Draft Interim Measures Workplan for Soil Cie anu at the Former SodiumDisposal Facility, Santa Susana Field Laboratory , i CF Kaiser Engineers, Inc .(June 18, 1999) .
Revised by DTSC, PEAS 7/13/99
49
HDMSP00028265
•
•
13 . Draft Final Former Sodium Disposal Facility, Santa Susana Field LaboratoryCharacterization Report, ICF Kaiser Engineers (August 15, 1997) .
14 . Geophysical and Hydrologic Testing Surveys, Rocketdvne/Santa Susana FieldLaboratory, Ventura County, California , Harding Lawson Associates(November 2, 1995 )
15 . Grading Permit Modification, FSDF Interim Action, Rocketdyne Santa SusanaConditional Use Permit 248 : Permit No . 8664, Ventura County Air PollutionControl District (June 1999 )
16 . Groundwater Remediation Operations Workplan, Boeing North American, Inc .,Rocketdvne Propulsion and Power, Santa Susana Field Laboratory, Areas I & III,(May 25, 1990, Revised April 21, 1998) .
17 . Guidelines for the Preparation of Air Quality Impact Analyses , Ventura CountyAir Pollutions Control District (October 24, 1989 )
18 . Memorandum : Sensitive/Rare Plant Protection During FSDF InterimMeasures , Michael Sullivan, Boeing North American, Inc . (September 15,1998) .
19. Padre Associates letter to IT Corporation and attachments, (May 14, 1999) .
20 . Public Participation Plan for the Closure of the Former Sodium Disposal Facility.Santa Susana Field Laboratory, Ebasco (July 1991) .
21 . RCRA Facility Investigation Workplan Addendum, Santa Susana FieldLaboratory, Ventura County, California , Ogden Environmental and EnergyServices, Inc . (September 1996) .
22 . South Coast Air Quality Management District , Personal conversation withJonathan Nadler (August 1998) .
23 . Ventura County Air Pollution Control District , Rule 50, Rule 51, and Rule 74 .29 .
24 . Ventura County Air Pollution Control District , personal conversation withDouglas Tubbs on attainment status for ambient air quality standards(August 26, 1998) .
25. Ventura County Air Pollution Control District, Correspondence onemissions from heavy duty equipment operation, (September 16, 1998) .
Revised by DISC, PEAS 7/13/99
50
26 . Ventura County Air Pollution Control District, Correspondence on Threshold• Emissions from Short Duration Construction Projects (June 29, 1999) .
•
Revised by DTSC, PEAS 7/13/99
51
ZmzoX
91A 9 91
HDMSP00028268
Appendix N
CEQA Notice of Determination andMitigated Negative Declaration
JAN-18-2000 10 :57 DTSC-EXT.RFFflIRS 916 327 e97H F .kL3/kl?
M
Winston H_ HickoxSecretary forEnvironmental
Protectio n
•
ijt J)
DE CDEC 2 0 19 92 0 ]999ju JSTATE CLEARINGHOUSE
California Environmental Protection Agency
Department of Toxic Subst ances Control
Edwin F . Lowry, Director10151 Croydon Way, Suite 3
Sacramento, California 95827-2106
NOTICE OF DETERMINATION
Tos Office of Planning and Research
1400 Tenth Street
Sacramento , CA 95814
Fra®: Department of Toxic Substances Control
Office of Program Audits & Environmental Analysis
400 P Street, Fourth Floo r
P .O . Box 806
Sacramento , CA 95812-0806
Project Title :
Interim Measures for Former Sodium Disposal Facility (FSDF), Santa Susana
Field Laboratory, Simi Hills, Californi a
State Clearinghouse Number :
99071048
Contact Person and Telephone :
Gerard Abrams
Department of Toxic Substances Control
(916) 255-3600
Project Location :
Gray DavisGovernor
The FSTbF is located on the west end of the Boeing North American, Inc ., Santa
Susana Field Laboratory ( SSF'L ) at the end of Woolsey Canyon Road in Simi
Hills, California _ Simi Hills is in southeastern Ventura County . The SSFL is
as 7 .5 minute quadrangle at Township 2 North , Range 17
HDMSP00028270
JRN-10-2000 1 : 57 DTSC-EXT .AFFAIRS
• Notice of Determination
interim Measures for the Former Sodium Disposal Facility
December 20, 1999
Page 2
Proj act Daaeription :
•
•
915 327 0978 P .04i07
The Interim Measure (IM) will remove approximately 3,240 cubic yards of soil
contaminated with polychlorinated biphenyls (PCB), dibenxo-dioxins/ furans
(dioxin), and mercury from the Former Sodium Disposal Facility (FSDF) .
The contaminated soil will be removed from the upper pond , the area to
the west of the pond , and three drainages--channel A, channel B, and channel
C--that lead away from the lower pond to the north . The soil in these areas
will be removed down to bedrock . Moreover , stained weathered bedrock will be
scraped off and disposed . The contaminated soil and bedrock will be
transported off-site to Chemical Waste Management , Kettleman Hills for
disposal .
The excavated areas in the upper pond, western area , and a portion of
drainage channel B will be backfilled with approximately 13,000 cubic yards of
clean low permeability clay fill . The backfilled areas will teen be
revegetated with native plant species . Inspection and maintenance will be
performed at the end of each significant rain event as defined in the facility
NPDES permit , until the implementation of the corrective measures study .
Data project approved : December 14, 199 9
This Notice of Determination is filed in compliance with Section 21108
of the Public Resources Code . The Department of Toxic Substances Control
(Department), as lead agency, has approved the above described project and the
attached Mitigated Negative Declaration .
On the basis of the Initial study the project could have a significant
effect on the environment unless mitigated . Mitigation measures have been
added to the project to reduce these effects to less than significant levels .
The attached Mitigated Negative Declaration was prepared for this
project pursuant to the provisions of CEQA .
A copy of this Mitigated Negative Declaration may be examined at the
above address of the Department of Toxic Substances Control .
Signature :Branch Chief
Date raeejved for filing at OPR : 12/20199
Date :
HDMSP00028271
JRN-18-2888 18 :58 DTSC-EXT .1FFAIRS 916 327 8978 P .85/8Y?
Department of Toxic Substances Contro l
Winston H. HickoxSecretary forEnvironmentalProtection
Edwin F . Lowry, Director10151 Croydon Way, Suite 3
Sacramento, California 95827-2106
MITIGATED NEGATIVE DECLARATIONfor
Interim Measure for the Former Sodium Disposal Facilit y
•
1 r ieect Proponent:
Boeing North American, Inc .6633 Canoga AvenueP.O. Box 7922Canoga Park, California 91309-7922
Contact: Mr. David Dassler(818) 586-4069
Gray DavisGovernor
Project DescriptionThe Interim Measure (IM) will remove approximately 3,240 cubic yards of soil
contaminated with polychlorinated biphenyls (PCB), dibenzo-dioxins/furans (dioxin), andmercury from the Former Sodium Disposal Facility (FSDF) . The cleanup goal for PCB is 600rig/kg (parts per billion), and dioxin is 13 .1 ng/kg (parts per trillion) . Soil that contains mercurywith a concentration greater than or equal to 20 parts per million will be disposed as hazardouswaste. In addition, any metallic debris encountered will be segregated and screened forradioactivity before disposal, and analysis for perchlorate will be included in the verificationsamples since it was detected in groundwater beneath the FSDF .
The contaminated soil will be removed from the upper pond, the area to the west of the
pond, and three drainages--channel A, channel B, and channel C--that lead away from the lower
pond to the north. The soil in these areas will be removed down to bedrock . Moreover, stained
weathered bedrock will be scraped off and disposed . The contaminated soil and bedrock will be
transported off-site to Chemical Waste Management, Kettleman Hills for disposal .
The excavated areas in the upper pond, western area, and a portion of drainage channel 13
will be backfihIed with clean fill similar to the native soil . The clean fill soil will be compacted
upon placement to reduce the potential for erosion and subsequent migration of sediment down
the drainage charnels . The backfllled areas will then be revegitated with native plant species .Inspection and maintenance will be performed at the end of each significant rain event as defined
in the facility NPDES permit, until the implementation of the corrective measures study .
The estimated duration of the project is twelve weeks .
California Environmental Protection Agency
HDMSP00028272
JRN-10-2000 1 :58 DTSC-EXT .RFFAIRS '91b 2? 0Y?H F' db/k1 r
Project Location:The FSDF is located on the west end of the Boeing North American, Inc., Santa Susana
Field Laboratory (SSFL) at the end of Woolsey Canyon Road in Simi Hills , California. Simi
Hills is in southeastern Ventura County. The SSFL is in the USGS Calabasas 7.5 minute
quadrangle at Township 2 North, Range 17 West. The SSFL consists of 2,668 acres and issubdivided into four administrative areas and a buffer zone . Areas I and III are owned and
operated by Boeing 'North American, Inc ., Area H is owned by NASA, and Area N is owned by
Boeing North American and operated by the Department of Energy (DOE) .
Findings of Potentially Significant Effect Unless_Mitigated :The Department of Toxic Substances Control (DTSC) finds that the proposed project will
have a potentially significant effect on the environment unless mitigated . Mitigation measures
have been added to the project to reduce these effects to less than significant levels . The Initial
Study which supports this finding is attached .
Mitigation Measures :The following mitigation measures have been incorporated inc the project to
reduce potential impacts to AIR and are included in the draft Interim Measure Workplan .
1) Maintain equipment engines in good condition and in proper tune as permanufacturer's specifications .
2) During smog season (May through October), the construction period should belengthened so as to minimize the number of vehicles and equipment operating atthe same time .
3) Construction activities should utilize new technologies to control ozone precursoremissions as they become available and feasible.
4) Transportation of contaminated soil off-site will be limited to the hours of 9 :00
a.m. - 3 :00 p.m. and 7:00 p.m. and 9:00 p .m.5) Transportation activities for import fill will be limited to non-peak hours or the
number of daily trips will be limited so that daily vehicle emissions will notexceed the projected daily NOx emissions for non-peak hour transportation .
These mitigation measures are detailed in the attached Initial Study .
Signature Date ZProject anager
Signature ~✓ DateBranch Chief
Rcvuad by DTSC . PEAS 7113199
Rocket.nd
HDMSP00028273
Recommended
