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C H I C A G O

D A L L A S

LOS A N G E L E S

S I D L E Y & A U S T I NfAtTNIKSHtr INCLUDING fKOrif SIGNAL COKfOlATIONS

1722 EYE STREET, N.W.WASHINGTON, D.C. 20006TELEPHONE 202 736 8000FACSIMILE 202 736 8711

FOUNDED 1866

NEW YORK

L O N D O N

S I N G A P O R E

TOKYO

WKITICS D I R E C T N U M I I X(202)736-8197

VIA FEDERAL EXPRESS

February 21, 1997

Docket Coordinator, HeadquartersU.S. Environmental Protection AgencyCERCLA Docket Office1235 Jefferson Davis HighwayCrystal Gateway #1, First FloorArlington, VA 22202

Re: USEPA Proposed Rule, NPL Nomination, 61 Fed. Reg.67678 (Dec. 23, 1996)

To Whom It May Concern:

The General Electric Company ("GE") submits theattached comments on the Proposed Rule issued by the UnitedStates Environmental Protection Agency ("USEPA"} on December 23,1996, proposing to add the Grand Street Mercury Site, Hoboken,New Jersey ("Site") to the National Priorities List ("NPL"). 61Fed. Reg. 67678 (Dec. 23, 1996). The USEPA proposes to list theSite on the NPL based on 40 C.F.R. § 300.425(c)(3).

GE has a substantial interest in the Site. GE has beenidentified by the USEPA as a potentially responsible party("PRP") for the Site and is involved in private litigationrelated to the Site, including claims under the ComprehensiveEnvironmental Response, Compensation, and Liability Act, 42U.S.C. § 9601 et seq. ("CERCLA").

GE appreciates the opportunity to submit these commentsto the USEPA and urges the USEPA to take into account the pointsand observations raised herein as part of the rulemaking process.

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S I D L E Y & A U S T I N

Docket Coordinator, HeadquartersFebruary 21, 1997Page 2

WASHINGTON, D.C.

Respect fully submitted,

Langle^y R./<3Jiooket Sf( Bass

Sidley & Austin22 Eye Street, N.W.

Washington, D.C. 20006(202)736-8000

Attorneys for General Electric Co.

\Attachment

cc: Jane W. Gardner, EsquireGeneral Electric Co.

1000002

COMMENTS ON THE NATIONAL PRIORITIES LISTNOMINATION OF THE GRAND STREET

MERCURY SITE, HOBOKEN, NEW JERSEY

INTRODUCTION

Background

PTI Environmental Services (PTI) has prepared these comments on the NationalPriorities List (NPL) nomination of the Grand Street Mercury site, Hoboken, New Jersey("the Site"), on behalf of the General Electric Company. The Site was nominated for theNPL under the provisions of Section 300.425 (c) (3) of the National Contingency Plan

(NCP). Under these provisions, which are an alternative to the more commonly usedprocess of scoring sites using the Hazard Ranking System, the site must meet all three ofthe stated criteria, which include the issuance of an Agency for Toxic Substances andDisease Registry (ATSDR) advisory recommending dissociation of individuals from therelease, a determination that the release poses a significant threat to public health, and theanticipation that it will be more cost effective to use remedial authority than to useremoval authority to respond to the release. The nomination memorandum, from RichardL. Caspe to David Evans, has four documents attached in support of the assertions madewith regard to these three criteria. These documents are:

• Public Health Advisory for the Grand Street Mercury site prepared byATSDR, dated January 22,1996

• U.S. Environmental Protection Agency (EPA) Action Memorandumfor the Grand Street Mercury Site, dated March 2,1996

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Sampling and Analysis information for characterization of vapors,personal belongings, soils, and building materials

Cost analysis for potential response actions.

Scope and Summary

This document provides comments on the attachments to the nomination memorandum•

listed above, focusing on the issues summarized below:

Action Memorandum

Lack of reasonable basis for the fire scenario.

Lack of consideration given to the functioning of the building sprinklersystem, the fire alarm system, or the likely fire department response.

Misinterpretation of the impact that the interior partitioning will haveon possible fire scenarios.

Unfounded assertions regarding higher than typical potential forbuilding structural collapse.

Lack of reasonable basis for the assumption regarding mercury releaseduring a fire.

Selection of models to represent the complex plume dynamics from anuncontrolled fire. None of the selected models are based oncomparable situations.

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• Selection of models to represent the complex air movement patterns inan urban area. None of the models simulate the effects of a series ofbuildings.

• Selection of input parameters for the models, notably themeteorological conditions and mercury release rate.

These issues combine to suggest that the information presented in the nominationmemorandum does not support the assertion that the Site poses a significant threat topublic health. The threat posed to public health is no greater, and possibly even less, thanwould be posed if the building were still an active industrial facility, a use for which thebuilding in its current condition would be considered completely acceptable.

Public Health Advisory

• ATSDR (1996) has not shown that a urine mercury concentration of20//g/L is a valid basis for judging imminent health hazard

• The reported urine concentration data for the former Grand Streetbuilding residents are not sufficient to characterize chronic exposure orpotential health effects.

While PTI is not intending to suggest that this former industrial building is currentlysuitable for long term residential use, the use of a urine mercury concentration of 20 //g/Las an indicator of imminent health hazard is not supported. Further, we are not aware thatthis urine mercury level has been established by any regulatory authority as an indicator

of human health risk. These issues also lend further support to the lack of significantthreat to public health from the Site.

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Cost Analysis

The five remedial elements presented in Attachment 4 to the NPLnomination package were not sufficiently well described to allow

independent evaluation of the associated cost estimates

The relevance of the building reconstruction for the NPL nominationprocess is not clear, given the consideration of a permanent relocation

option at approximately one third the cost estimated for buildingreconstruction

The nomination memorandum does not clearly demonstrate that use ofremedial authority will be more cost-effective than use of removalauthority.

ACTION MEMORANDUM

Fire Scenario

Section HI (A) (iv) (ppl3-14) of the March 21,1996 EPA Action Memorandum presentsthe EPA analysis of the threat of a fire or explosion at the Grand Street building.

Additionally, Section 2.2 of Attachment F (Weston, 1996) to the EPA ActionMemorandum presents the assumed mercury release rate from the fire scenario that wasused as input to the dispersion modeling exercise.

In this analysis of the threat of a fire or explosion, EPA makes the erroneous assertionthat "The potential for an intense, long burning fire, which is slow to extinguish and is aproducer of large volumes of smoke is greater in a building of the Grand Street type ofconstruction. Heavy water runoff and structural collapse is also a greater potential at the

Grand Street building than at the average type building due to the type of constructionand the fire load." Sources of error in this statement include the following:

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1000006

The primary contribution to the fire load and fire spread potential isthe building contents, and since this building is vacant without anyfurnishings, the fire load (available combustion energy) and potentialfor accidental ignition and rapid fire spread is significantly less hi thisbuilding than in occupied buildings.

Contrary to the EPA assertion, partitioning of the building withsheetrock walls and with rated fire barriers in accordance with the localbuilding code reduces rather than exacerbates die fire hazard.Additionally, some of the interior walls are brick, which would beeven more effective than sheetrock at limiting fire spread. Thepartitioning will restrict or limit fire spread and will allow smokedetectors and sprinklers to actuate earlier than they would in anundivided area. Furthermore, the partitioning will limit the number ofsprinkler heads that open hi response to a fire, thereby minimiring thewater runoff and potential for any water induced damage to thebuilding.

In view of the issues described above, we would expect fewersprinklers to open, thereby discharging less water, "than at the average

building," which was never defined by EPA, but which we assume tobe an industrial, commercial, or multi-resident building with aconventional sprinkler system. Similarly, the anticipated rapid firedepartment notification and correspondingly smaller fire size upon firedepartment arrival, should allow them to finish extinguishing the firewith a smaller hose stream or standpipe discharge "than at the averagetype of building." Therefore, there should not be any unusual threat ofstructural collapse providing the water runoff is allowed to drain

normally from the building.

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• It is relatively easy either to remove the duct tape and "other

improvised coverings" on the sprinkler heads and/or replace damagedheads. In fact, we understand from Mr. Harmon, the On-SceneCoordinator, that this already has been completed. Furthermore, weunderstand that the fire alarm system is wired to a central monitoringstation and that mis system is being maintained in an operationalcondition. Therefore, assuming the sprinkler control valves are lockedopen or electrically supervised, the sprinkler system should easilycontrol a fire and the central fire alarm system will allow rapid firedepartment response to complete the extinguishing of any residual

burning.

• There are numerous reports of fires being controlled with negligibledamage in vacated sprinklered buildings. A sample report from theSeptember/October 1996 National Fire Protection Association (NFPA)Journal is presented below describing a fire in a vacant school buildingof construction similar to the Grand Street building. The onlysignificant damage in the fire was to the contents of the room of fireorigin.

The following is a verbatim reproduction of the account on page 25 of theSeptember/October 1996 NFPA Journal.

Sprinklers Control fire in Vacant SchoolVirginia

Sprinklers controlled a blaze in a vacant high school scheduled for renovations. The firebegan -when a fluorescent light ballast overheated and ignited ceiling tiles.

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The three-story structure, which measured 300 by 200 feet, -was constructed of heavytimber and concrete block walls with a brick veneer. The roof was built up over wooddecking. An unsupervised, wet-pipe sprinkler system protected the building, which hadno detectors.

It was a Sunday and the school was unoccupied when a passerby noticed smoke issuingfrom the building and called 911 at 6:49 a.m. Firefighters arrived two minutes later andfound light smoke coming from the rear of the school. Entering through the back, theyfound heavy smoke on the first floor and two sprinklers operating to control a small firein a storage room. Firefighters used a I'/j-inch handline to complete extinguishment andpositive-pressure ventilation to remove the smoke from the building.

Firefighters determined that a fluorescent light fixture in the storage room had been lefton and that the ballast had overheated and ignited low-density fiberboard ceiling tiles.Heat from the fire fused two sprinklers, which activated to control the blaze.

Fire damage was limited to the room of origin, but smoke spread throughout the entirebuilding. Damage to the school, valued at $4 million, was estimated at only $500.However, the storage room in which the blaze started contained new electronic votingmachines, which were damaged by smoke and by water from the sprinklers andfirefighters ' handline. The contents of the room, valued at $500,000, were a total loss.

EPA also claims in the Action Memorandum that the water supply for fire suppression isnot adequate. We understand, to the contrary, that the water supply has been reviewed byHoboken fire department officials and found to be adequate for fire fighting.

EPA assumptions to characterize the source term for mercury vapor dispersioncalculations are also questionable. The mercury vapor release rate used for the dispersionmodeling presented in Attachment F is assumed to be 1,000 pounds per hour, based

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presumably on the fire scenario described in the Action Memorandum. There is nosubstantiation of the release rate and duration because the inventory of mercury in the

building is not known, and the particulars of the fire scenario are not stated. Neither theAction Memorandum nor Attachment F contain any acknowledgment of the enormousuncertainty inherent in this release rate, which was the source term used in all three*dispersion modeling scenarios.

The only rationale for assuming a high mercury release rate over one hour is the•

erroneous assertion that the sprinkler system is inadequate for this occupancy and that thefire department response will not be effective. However, based on the precedingdiscussion, the sprinkler system should function as designed and easily control a fire as

well as provide early notification to facilitate prompt fire department response to thevacant building. The presence of smoke detectors in many of the condominium units willalso serve to provide an early alarm. Given the close proximity of a fire station and thepresence of a working wet pipe sprinkler system, the expected duration of a flaming fireis more likely to be 5 to 15 minutes than one or more hours. It is not possible, however,

to make a realistic estimate of the mercury release rate without assuming a specific firescenario including: fire location; fire heat release rate history; fire spread; response of fireto sprinkler system actuation; fire department response; and mercury quantity, form(puddle, droplets, or adsorbed on a porous surface), and location in the fire area. Evenwith these assumptions, some laboratory testing may be needed to obtain realisticmercury vaporization rates.

Dispersion Modeling

Meteorological Parameters

The key meteorological parameters for the dispersion models are wind speed and ambienttemperature.

^000010o0 •.-topl_co-1.doc

Two different wind speeds were used to construct two scenarios for the INPUFF model.Both wind speeds used, 1.0 m/s and 2.0 m/s, represent calm conditions, which wasconsidered the worst-case scenario. During a fire, calm conditions would limit thedispersion of mercury released from the bum and maximize the concentration of mercuryhi the air in close proximity to die building. However, the two wind speeds used in themodel do not accurately characterize the meteorological conditions for this region of NewJersey. Data obtained from EPA's SCRAM bulletin board system for Newark, New

•

Jersey, indicated that wind speeds of less than 1.5 m/s occurred only once during the8,784 observations made in 1992. Given this data, further justification needs to be

provided for wind speed selection in the modeling exercise.

We were not able to determine with certainty which ambient air temperature was chosen*

for the modeling exercise. The Section 2.5 summary in Weston (1996) gives an airtemperature value of 295 °K, which differs from the air temperature of 12°C given in thetext summary section of the report. An air temperature of 295°K is equal to 22°C, whichis typical of summer temperatures hi New Jersey. An ah* temperature of 12°C is similarto the annual average temperature for the state of New Jersey. A 3-year averagegenerated from annual average temperatures for the years 1994-1996 for state of NewJersey is 11.3°C (data obtained from National Weather Service world wide web site:

www.nws.noaa.gov).

Mercury Emission Rate

In the event of a fire, the emission rate for mercury from the building depends on manyparameters, including the characteristics of the fire and the amount and distribution ofmercury hi the building. Specific issues include the temperatures reached at locationswhere mercury is present, the duration that temperatures high enough to volatilize

1000011** t:\nptjM-l.doc

mercury are maintained, and the state of the mercury at that location. For example, inretort operations designed to volatilize and recover mercury, it takes 12 hours attemperatures ranging from 650°C to 800°C to process bricks. Weston (1996) assumes afire duration of 1 hour, during which 1,000 Ib. of mercury would volatilize, but it doesnot discuss at all how these assumptions relate to the fire scenarios described in theAction Memorandum and discusses in only an extremely cursory manner how the1,000-lb release assumption was derived. Issues regarding the fire scenario and mercuryemission rate were also discussed in the previous sections.

Modeling Theory and Selection

In any model there is a certain amount of error or uncertainty. Of course, the morecomplete and accurate the data input into the model, the more reliable the results will be.This is true even when the physical situation is modeled by a tool developed specifically

"for that purpose and with the appropriate physics, algorithms, and equations. Specificconcerns regarding reliance on the model results presented in Weston (1996) for decisionmaking are based on the following key issues:

• Significant uncertainty and error exists in the input of knownconditions

• The models used in Weston (1996) contain inadequate physics formodeling an uncontrolled urban area fire scenario.

All of the models used hi Weston (1996), which are further discussed below, are based onGaussian dispersion theory. Weston (1996) provides a cursory review of Gaussiandispersion theory, although not nearly enough to critically analyze the modeling effortsthat were conducted. However, the brief summary clearly identifies one of the inherentflaws in attempting to take Gaussian models, developed for other purposes, and apply

1000012

them to situations such as the Hoboken fire scenario. Weston (1996) says "actualdispersion is insoluble because there are more variables than data. ' Therefore, fieldstudies were conducted to produce data to fill in some of the variables." That is, whenthe model algorithm was developed, someone physically observed the "real world"situation and attempted to develop algorithms that represented that phenomenon.

For example, one of the variables is Effective Stack Height (H), which is actually theheight of the stack and the plume rise. In developing these types of models, field studies

" »

were conducted to develop formulas for calculating plume rise from a variety of sources(e.g., smokestacks or gas flares). However, it is unlikely that model developers useduncontrolled building fires in developing plume rise algorithms. Therefore, anyapplication of these basic air quality models will not be able to accurately predict theplume rise from an uncontrolled burning of the Grand Street building. Only casualobservation is needed to show that plume rise from a building on fire is significantlydifferent than that from a smokestack or gas flare. Correctly estimating plume rise iscritical to predicting downwind ambient air concentrations.. Given the uncertainty presenton this basic issue, a more rigorous analysis of plume rise equations, Gaussian dispersiontheory, and other model variables is warranted prior to basing decisions on this modeling

exercise.

The extent to which an air quality model applied by competent modelers is acceptable forthe evaluation of a contamination source depends on many factors, including:

• Meteorological and topographic complexities of a site

• Level of accuracy and detail needed for analysis

• Accuracy and understanding of model input data needed.

The meteorology and topography of the Site are complex. The Site is in a highlyindustrialized and urban area. Section 2.5 of Weston (1996) begins with the statement

1000013• •

"Modeling air dispersion in urban environments is difficult" The three models used inWeston (1996) may not be capable of adequately representing the complex nature of theHoboken environment. Similarly, these models do not provide refined analyses. Theyare best characterized as screening models. Given the importance of accurately assessingpotential risk from the Site, the use of screening models may not be adequate. Finally,the accuracy of data input into the model is critical. Data input parameters formeteorology and mercury emissions have been previously discussed, but are noted here

to stress importance.

Weston (1996) uses three air quality dispersion models to calculate the ambient airquality concentration of mercury at and near the Site in the event of an uncontrolled fire.The three models are the Integrated PUFF Model (INPUFF), the SCREEN model, and the

Areal Location of Hazardous Atmospheres (ALOHA) model. None of the above modelswere designed to predict ambient air quality concentrations from an uncontrolled buildingfire in an urban environment such as Hoboken, New Jersey.

The INPUFF model was developed to model emissions from ocean-going incinerationships and has been applied to a variety of other sources. The INPUFF model is aGaussian model used for modeling the accidental release of substances and is used tocalculate effects from semi-instantaneous and continuous point sources. The INPUFFmodel was used as the primary tool in assessing the dispersion of mercury from the Site.

The secondary model used in Weston (1996) was the SCREEN model. This computermodel is based on EPA's "Screening Procedures for Estimating the Air Quality Impactsof Stationary Sources." This model contains screening techniques for chemically stablegases and fine particulate matter. In addition to the SCREEN model's ability to calculatemaximum downwind concentrations, it can also predict the effect of building downwashfrom a source. Downwash is the creation of turbulent eddies immediately downwind ofan obstacle such as a building. It appears that Weston (1996) used the SCREEN model to

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calculate the concentrations of mercury adjacent to the building. Concern regarding this

use of SCREEN is discussed below.

Finally, Weston (1996) uses the ALOHA model as a check on the other modeling efforts.As with the other models used in Weston (1996), the ALOHA model was not designed tocalculate ambient air concentrations from a source such as an uncontrolled fire. TheALOHA model is more generally used by fire departments and other first responders toconservatively calculate maximum likely exposures.

EPA Guidelines on Air Quality Models (July 1986) states that "Air quality models havebeen applied with the most accuracy or the least amount of uncertainly to situations oflong-term averages in areas with relatively simple topography." This statement is almostcompletely opposite to the simulation provided in Weston (1996) that attempts to applyvery simplistic models to predict short-term impacts of a catastrophic release in an area ofcomplex topography and meteorology. Given the reasons noted above, a more rigorousanalysis of modeling tools is required prior to developing an effective source controlstrategy. Individual components of the modeling exercise that are of particular concernare discussed below.

One of the primary reasons that the SCREEN model was used in Weston (1996) was tocalculate the effect of building downwash and provide predictions in the near wake, farwake, and cavity recirculation zones. Figure 1 in Weston (1996) graphically presents theconcept of building downwash. SCREEN was developed to evaluate industrial stackemissions. The physics of an uncontrolled fire, however, are significantly different thanan industrial stack emission. In Weston (1996), a virtual stack with a diameter of 7 m anda height of 0 above the roof line has been created. Results from this disappearing stack(height of zero) cannot be considered reliable.

Another example of problems in attempting to model downwash effects with theSCREEN model at the Site is easily pointed out in Figure 1 of Weston (1996). The

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cavity recirculation area is shown to be a 43-m apron around the building. However, onlyin one direction, the direction the wind does not often blow, is there a 43-m-long areaadjacent to the building that could support a cavity recirculation area at the Site. In short,the downwash-related effects need considerably more attention and there is reasonableconcern over the use of the downwash predictions developed by Weston (1996).

Based on the documentation provided in Weston (1996), it is unclear how several key airquality modeling parameters were handled. For example, the INPUFF model allows forbuoyancy-induced dispersion (BID) to be calculated. This feature is offered becauseemitted plumes will undergo a certain amount of growth during the plume rise phase dueto turbulence of the plume and turbulence of entrained ambient air. It is anticipated thatBID would be much greater in an uncontrolled fire scenario than from a tall smokestack.The BID feature is offered as an option in the INPUFF model, rather than as a requiredelement, because many times it is not needed. BID will generally not have a large effecton predicted concentrations unless the stack height is small compared to plume rise,which is exactly the case presented by Weston (1996), where the stack height is zero. Itis not clear from the information provided how BID affects were represented.

Also, it is unclear how deposition of mercury was handled. In the situation of anuncontrolled fire, there would be a significant generation of large participate matter (e.g.,soot or ash). As the mercury vapor cools within the plume, a certain amount of themercury will seek particulate matter or water to which to bind, resulting in deposition ofmercury. It is unclear from Weston (1996) how rigorously depositional effects wereconsidered. The influence of this association of mercury with particulate matter isdiscussed below.

Also unclear in Weston (1996) is the issue of mercury chemistry and transformationswithin the plume. As alluded to previously, mercury vapor and mercury bound toparticulate matter or water have very different depositional velocities. Also, mercuryspecies that may be found in the plume of an uncontrolled fire have different scavenging

1000016

efficiencies by droplets and different dry deposition rates. Also, mercury vapors andparticulate-bound mercury have very different human health related consequences. Thus,a complete risk analysis of mercury speciation and transformation is needed to accuratelypredict the transport and fate of mercury from the fire scenario.

Mercury Health Effects Evaluation

Industrial exposure standards were used to evaluate health effects related to the plume ofmercury estimated to be released from a fire at the Grand Street building. However, noevaluation was presented demonstrating that the assumptions behind development ofthese values for industrial exposures are appropriate for the fire scenario exposure.

Health effects of mercury depend on a variety of issues, such as speciation andassociation with other media. For example, experimental evidence suggests thatapproximately 74-80 percent of inhaled metallic mercury (Hg°) is absorbed, whereasonly approximately 40 percent of inhaled divalent mercury (Kg**) is absorbed. There arealso differences in bioavailability depending on the physical form of the mercury. Forexample, aerosol droplets of Hg are more likely to be ingested than inhaled, resulting inmarkedly lower bioavailability. Similarly, inorganic mercury adsorbed to largerparticipate matter from the fire (ash), is more likely to be ingested than inhaled deeplyinto the lung, in contrast to mercury in the vapor phase. Ingested mercury would begenerally less bioavailable than inhaled mercury. A more comprehensive review ofexpected conditions under the fire scenario is needed to adequately predict health effects.

PUBLIC HEALTH ADVISORY

The EPA Site Action Memorandum, dated March 21, 1996, used mercury levels in theurine of residents and workers as an indicator for individual mercury exposure and statedthat "Adverse health effects are associated with mercury levels greater than 20 ;/g/L."

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This urinary mercury concentration, however, may not be an appropriate measure ofmercury exposure or an appropriate indicator of an imminent health hazard. TheHoboken Health Department (HHD) and the Hudson Regional Health Commission(HRHC) reported urinary mercury concentrations for 31 Grand Street residents andworkers that ranged from 3 to 102 //g/L. Corrected for urinary output (i.e., normalizedper gram creatinine excretion), these urinary concentrations ranged from 3 to 134 //g/gcreatinine. The PHA indicates that more than 69 percent of these individuals exceededthe urine mercury level of 20 //g/L. HHD and HRHC data were not available for PTI toreview prior to preparation of these comments. Nevertheless, based on our review of thePHA and other materials, the use of a 20 //g/L mercury level in urine to indicate animminent health hazard warrants comment. The following sections briefly discussseveral problems apparent in the assessment of urine mercury concentrations and theevidence for the suggestion that urine mercury concentrations exceeding 20 //g/L indicatepresence of an imminent health hazard.

Limitations in Assessment of Mercury Exposures

The EPA Site Action Memorandum, dated March 21, 1996, suggests that urine samples,taken from individuals during a single urination event (i.e., a spot sample), were used asan estimate of mercury exposure to Grand Street building residents and workers. Severalstudies in the peer reviewed literature caution against the use of a single spot urinesample to estimate mercury exposure in humans. This is because several factors canaffect mercury concentrations in urine, resulting in large day-to-day variability (Buckellet al. 1946; Goldwater 1964; Stewart et al. 1977; Tucker et al. 1979, Levine et al. 1982).

Large day-to-day variability in mercury urine levels may be due to mercury exposurefrom other sources. For example, urinary mercury levels increase following ingestion of

fish tissues containing mercury (ATSDR 1994; EPA 1996) and from smoking (Roels etal. 1982). Roels et al. (1982) reported a median urinary mercury level of 45 //g/g

1000018•« K\npl_co-t.doc

creatinine for non-smoking workers at two facilities, a chlor-alkali facility and a batterymanufacturing facility. Smoking workers at these same facilities had urine mercurylevels that were more than double that of non-smokers (111 //g/g creatinine). As notedabove, Grand Street residents and workers were reported to have urinary mercuryconcentrations of similar magnitude, ranging from 3 to 134 //g/g creatinine. The PHAdid not, however, report either fish ingestion or smoking habits of Grand Street buildingresidents and workers or whether urinary mercury levels were higher hi smokers.

•

The relative contribution of different sources of mercury to the mercury measured inurine of former Grand Street residents can not be determined from the data PTI hadavailable to review. The EPA's Mercury Report to Congress (U.S. EPA 1996) indicatesthat exposure to elemental mercury via inhalation may result in urinary excretion of smallamounts of dissolved mercury vapor and sulfhydryl conjugates of mercury (cysteine orN-acetylcysteine). In contrast, exposure to methylmercury hi fish tissue can result inurinary excretion of methylmercury and inorganic mercury. Consequently, the form of

mercury hi urine may be important for identifying the relative contribution of varioussources of mercury to urinary mercury excretion. The PHA did not identify the type ofmercury excreted hi urine.

In conclusion, the data regarding mercury levels hi urine of Grand Street buildingresidents and workers is insufficient from which to base estimates of individual exposureto mercury in ah*. The available data are likely to show high day-to-day variability anddo not consider or identify additional sources of mercury to urine. They should not,therefore, be considered to reliably reflect long-term exposure to mercury in air.

Urine Mercury Concentration as an Indicator of Health Concern

The purpose of the recommended action hi the PHA, the removal of residents from theGrand Street building based on imminent hazard, is to reduce or eliminate exposure to

1000019•' . t:\apl_eo-t.doe

mercury that may result in the occurrence of neurological effects. The PHA reports thatunexposed persons have mean mercury levels in urine of 4 to 5 //g/L with an upper limitof 20 //g/L (ATSDR 1996). The PHA also reports that "urine mercury concentrations of20 to 100 //g/L are associated with subtle neurological changes, even before overtsymptoms occur" and that at higher urinary mercury concentrations (100 to 500 //g/L)these neurological effects become more pronounced (ATSDR 1996).

In the PHA, ATSDR (1996) justifies the use of the 20 //g/L mercury concentration inurine as an action level using the following reasoning:

"Urine concentrations of mercury in unexposed adults are less than 20 //g/L. Thislevel was exceeded by 69% of the residents of the building, which Indicates thatthey are being exposed to mercury at levels of health concern."

However, to the best of our knowledge no regulatory authority has established a mercury

urine concentration of 20 //g/L as a health-based trigger for regulatory action.

ATSDR briefly reports that some occupational studies have indicated neurological effectsat urine mercury concentrations of 50 to 100 //g/g creatinine and that renal effects havebeen demonstrated at urine mercury concentrations greater than 25 //g/L. However,

ATSDR has not supported its assertion that exceedance of a urine mercury concentrationof 20 //g/L indicates exposure to mercury at levels which create an imminent healthhazard. In fact, several studies indicate urine mercury levels need to be much higher(>500 //g/L) before they can be statistically correlated with neurological effects (Langolfet al. 1977; Henderson et al. 1978; Levine et al. 1982; and Fawer et al. 1983). In anotherstudy of occupationally exposed workers, Roels et al. (1989) was unable to show astatistically significant dose-effect relationship between mercury levels in urine (rangingfrom 15 to 231 //g/g creatinine) and hand tremors, a neurological effect which is,according to Fawer et al (1982) of questionable clinical significance. These studies do

1000020•" K\apl_co-l.<loc

not support the use of a urine mercury concentration of 20 //g/L to determine theexistence of and imminent health hazard.

In conclusion, there is insufficient data regarding the urine mercury concentrations inGrand Street residents and workers from which to assess exposure to mercury in air.Further, ATSDR has not supported its use of a urine mercury concentration of 20 //g/L todetermine existence of an imminent health hazard. Finally, to the best of our knowledgeno regulatory authority has established this urine mercury value as a level upon which tobase actions relating to imminent health hazard.

COST ANALYSIS FOR POTENTIAL RESPONSE ACTIONS

Attachment 4 to the NPL Nomination memorandum presents five remedial elements andassociated cost estimates. Clearly labeled supporting information on cost estimate

development is presented only for the building reconstruction element, but thatsupporting information does not provide sufficient information for independentevaluation of the cost estimate. Some detailed cost breakdowns are also provided, but theremedial elements to which that supporting detail applies is not clear. Nor is the rationalefor including both permanent relocation and building reconstruction, given that the

building reconstruction is estimated to cost nearly three times as much as permanentrelocation. Further, no rationale is presented for either the individual remedial elementsor howthey would be combined into remedial options.

NPL listing under the provisions of Section 300.425 (c) (3) require demonstration that itwould be more cost-effective to use remedial authority than removal authority to respondto the release. The NPL Nomination memorandum addresses time and money limitationsof the removal program, the greater flexibility of the remedial program, and the

availability of other funds, such as state contributions, under the remedial program, but

1^)000211Q19 ' K\npl_co-1.aoc

does not directly demonstrate that remedial response actions will be more cost-effective

than removal response actions.

CLOSING

The supporting documentation for the Grand Street Mercury Site NPL nomination hasseveral major weaknesses, discussed in these comments, that substantially undermineEPA assertions regarding the criteria which must be met for listing under NCP Section300.425 ( c ) (3). The ATSDR use of 20 ftgfL mercury in urine has not been shown to bean indication of an imminent health hazard, the Grand Street building has not been shownto pose greater risk to public health than any typical industrial building, and the greatercost-effectiveness of response actions under remedial rather than removal authority hasnot been substantiated.

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REFERENCES

ATSDR. 1994. lexicological Profile for Mercury (Update). TP-93/10. Agency forToxic Substances and Disease Registry, Public Health Service, U.S. Department ofHealth and Human Services. May 1994.

ATSDR. 1996. Public Health Advisory for 722 Grand Street (A288), Hobbken, HudsonCounty, New Jersey. Agency for Toxic Substances and Disease Registry, Division ofHealth Assessment and Consultation, Public Health Service, U.S. Department of Healthand Human Services. January 22.

EPA. 1996. Mercury Report to Congress. EPA-452/R-96-001d. PB96-184650. VolumeIV: Health Effects of Mercury and Mercury Compounds. SAB Review Draft.Environmental Protection Agency, Office of Ah* Quality Planning & Standards andOffice of Research and Development Washington, DC.

Buckell, M., D. Hunter, R. Milton, and K.M.A. Perry. 1946. Chronic mercury poisoning.Brit. J. Ind. Med. 3:55-63.(Cited in Stewart et al. 1977).

Fawer R., Y. De Ribaupierre, M.P. Guillemin, M. Berode and M. Lob. 1983.Measurement of hand tremor induced by industrial exposure to metallic mercury. Brit J.Ind. Ned. 40:204-208.

Goldwater, L.J. 1964. Occupational exposure to mercury in the Harben Lectures. J of theRoyal Institute of Public Health and Hygiene. 27:279-301. (Cited in Stewart et al. 1977).

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Henderson R., H.P. Shotwell, and L.A. Krauss. 1978. Analysis for total ionic, andelemental mercury in urine as a basis for a biological standard. Am. Ind. Hyg. Assoc. J.35:576-80. (Cited in Levine et al. 1982).

lyer, K. J. Goodgold, A. Eberstein, and P. Berg. 1976. Mercury poisoning in a dentist.Arch. Neurol. 33:788-90. (Cited in Levine et al. 1982).

Jacobs, M.B., A.C. Ladd and, LJ. Goldwater. 1964 Absorption and excretion of mercuryin man. Arch. Environ. Health. 9:454-63. (Cited in Levine et al. 1982).

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Langolf G.D., D.B. Chaffin, R. Henderson, and H.P. Whittle. 1977. Effects of elementalmercury exposure on urinary mercury, EMG, and psychomotor functions. In: Clinicalchemistry and chemical toxicology of metals. Sunderman W. ed. Amsterdam: Elsevier.(Cited in Levine et al. 1982).

Levine S.P., G.D. Cavender, G.D. Langolf and J.W. Albers. 1982. Elemental mercury

exposure: peripheral neurotoxicity. Brit. J. Ind. Med. 39:136-139.

Piikivi L. and U. Tolonen. 1989. EEG findings in chlor-alkali workers subjected to lowlong term exposure to mercury vapour. Brit J. Ind. Med. 46:370-375.

Roels H., R. Lauwerys, J.P. Buchet, A. Bernard, A. Barthels, M. Oversteyns and JGaussin. 1982. Comparison of renal function and psychomotor performance in workersexposed to elemental mercury. Int Arch. Occup. Environ. Health 50:77-93.

Roels H., S. Abdeladim, M. Braun, J. Malchaire and R. Lauwerys. 1989. Detection ofhand tremor in workers exposed to mercury vapor: A comparative study of threemethods. Environ. Res. 49:152-165.

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ShaperA.G., SJ.Pocock, D.Ashby.M. Walker and T.P. Whitehead. 1985. Biochemicaland haematological response to alcohol intake. Am. Clin. Biochem. 22:50-61.

Stewart W.K., H.A. Guirgis, J. Sanderson and W. Taylor. 1977. Urinary mercuryexcretion and proteinuria in pathology laboratory staff. Brit J. Ind. Med. 34:26-31.

Tucker WJ. 1979. A proposed sampling schedule for urinary mercury in occupationallyexposed workers. Ann Arbor: Department of Industrial and Operations Engineering,

•

University of Michigan. (Cited in Levine et al. 1982).

Weston, R. F. IncJKEAC, 1996. Final Report: Grand Street Mercury Site Air QualityModeling, Hoboken, New Jersey., Attachment F to the March 12, 1996 EPA ActionMemorandum for the Grand Street Mercury Site.

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