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ACCESSION NBR:9205040232 DOC.DATE: 91/12/31 NOTARIZED: NOFACIL:50-275 Diablo Canyon Nuclear Power Plant, Unit 1, Pacific Ga

50-323 Diablo Canyon Nuclear Power Plant, Unit 2, Pacific GaAUTH.NAME AUTHOR AFFILIATION

RUEGER,G.M. Pacific Gas & Electric Co.RECIP.NAME RECIPIENT AFFILIATION

DOCKET0500027505000323

R

SUBJECT: "Diablo Canyon Units 1 6 2 Annual Nonradiological EnvironOperating Rept,1991." W/920429 ltr.

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II

Pacific Gas and Electric Company 77 Beate Street

San Francisco, CA 94106415/973-4684

Gregory M. Rueger

Senior Vice President and

General ManagerNuctear Power Generation

April29, 1992

PG&E Letter No. DCL-92-109

U.S. Nuclear Regulatory CommissionATTN: Document Control DeskWashington, D.C. 20555

Re: Docket No. 50-275, OL-DPR-80Docket No. 50-323, OL-DPR-82Diablo Canyon Units 1 and 2Annual Nonradiological Environmental Operating Report

Gentlemen:

Enclosed is the 1991 Annual Nonradiological Environmental Operating Report forDiablo Canyon Units 1 and 2, submitted in accordance with Subsection 5.4.1 of the

Environmental Protection Plan, Appendix B to Facility Operating Licenses DPR-80and DPR-82.

Sincerely,

V

Gregory M. Rueger

CC: Ann P. Hodgdon (w/o enc.)William R. Leonard, CRWQCBJohn B. MartinTim Mazzacano, SLO County Environmental HealthPhilip J. MorrillCPUC (w/o enc.)Diablo Distribution (w/o enc.)

Enclosure

5727S/85K/ERE/1007

OL)OO~<,"9205040232 912231PDR ADOCK 05000275R PDR

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4

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PG Letter No. DCL-92-109

ENCLOSURE

1991 ANNUALNONRADIOLOGICALENVIRONMENTAL

OPERATING REPORT FOR DIABLO CANYON UNITS 1 AND 2

Pacific Gas and Electric CompanyApril 1992

5727S/85K

PG Letter No. DCL-92-109

PACIFIC GAS AND ELECTRIC COMPANYDIABLOCANYONPOWER PLANT

1991 ANNUALNONRADIOLOGICALENVIRONMENTALOPERATING REPORT

TABLE F NTENT PAGE

1 TI N ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 1

2 ENVIR NMENTALM RIN ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 8 1

2.1 AQUATICISSUES2.1. I2.1.2 Thermal Effec M nitorin Pr ram2.1.2 ~i* l 8 Al

2.1.4 te Mu el W tch Pro ram2.1.5 Oceano ra hic tudies

2.2 TERRESTRIAL ISSUES ............2.2. I2.2.2 Herbicide A lica ions2.2.3 Preservati n f Archaeolo ical Re rce

1

1

1

.. 222

.. 2

.. 234

3 NU AL R IMPORTANTENVIRONMENTALEVENTS.... ~........ 5

3.1 PEREGRINE FALCON3.2 SOUTHERN SEA OTTER....3.3 CALIFORNIAGREY WHALE .

3.4 BROWN PELICAN3.5 ELEPHANT SEAL

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 5

~ ~ ~ 5... 6

4 PLANT N ISTEN Y RE IREMENT ........................ 6

4.1 DESIGN CHANGES ....,..................,........... 6

5 PLANT REPORTIN RE IREMENT ......................... 7

5.1 EPP NONCOMPLIANCE.5.2 CHANGES IN STATION DESIGN5.3 NONROUTINE REPORTS

.. 777

~A............................................ 86

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PG Letter No. DCL-92-109

The 1991 Annual Nonradiological Environmental Operating Report is submitted inaccordance with the requirements of the Environmental Protection Plan (EPP), Appendix Bof Facility Operating Licenses DPR-80 and DPR-82, to describe implementation of the EPPand to demonstrate that the plant is operating in an environmentally acceptable manner.PG&E remains committed to the minimization of impact of Diablo Canyon Power Plant(DCPP) operation on the environment.

2 ENVIR NMENTALM NIT Rl

2.1 AQUATIC ISSUES

Aquatic issues are addressed by the effluent limitations, and monitoring and reportingrequirements contained in the DCPP National Pollutant Discharge Elimination System(NPDES) permit. The NPDES permit includes applicable requirements of the StateWater Resources Control Board's Ocean Plan and Thermal Plan.

2.1.1 Routine Monitorin

Quarterly NPDES reports containing routine influent, effluent, and receiving watermonitoring data and permit compliance summaries were submitted to the RegionalWater Quality Control Board, Central Coast (CCRWQCB) by the 20th day of themonth following the end of the respective quarter. An annual NPDES report wasalso submitted to the CCRWQCB on February 26, 1992. This report containedboth tabular and graphical summaries of the monitoring data obtained during1991. A summary of permit compliance for 1991, including corrective actions fordeviations from requirements, was also contained in this report. Both NPDESquarterly and annual reports were submitted concurrently to the NRC.

No enforcement actions were taken by the CCRWQCB under the NPDES permitduring 1991.

2.1.2 Thermal Effec M ni orin Pro ram

During 1991, the NPDES ecological studies program, as required by theCCRWQCB, continued as the Thermal Effects Monitoring Program (TEMP).Sampling was conducted four times annually for most subtasks. The programmonitored intertidal and subtidal communities of invertebrates, algae, and fish inthe discharge cove and at stations north and south of DCPP. The 1991 TEMPReport was submitted to the CCRWQCB and the NRC on March 26, 1992. Thisreport described the biological studies of the near-shore marine environment as

related to the DCPP thermal discharge during the seventh year of commercialoperation. No notable changes were observed in the biological communities at thedischarge cove stations when compared to previous years of plant operation.

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2.1.3 n ieT xici t ie

Acute Bioassay Toxicity studies were conducted quarterly on DCPP effluent at theonsite Biological Laboratory. Quarterly chronic toxicity bioassays wereperformed using three test species to determine the most desirable test species forlong-term testing and to determine compliance with the toxicity objective in the1990 California Ocean Plan. Red abalone was selected as the test species and noconsistent chronic toxicity was measured. A report of these results from the one-

year screening period is being prepared for submittal to the CCRWQCB.

2.1.4 tate Mussel W ch Pr m

The California Department of Fish and Game (CDF&G) maintains an in-situmussel assay program at several stations in the vicinity of DCPP. Results arereported directly to the CCRWQCB by CDF&G.

n hic udie

Physical and chemical oceanographic studies were conducted by PG&E in thevicinity of DCPP during March, June, and October 1991. Studies normallyconducted in February were repeatedly postponed due to consistent, adverse stormconditions. Temperature, dissolved oxygen, and pH were monitored at 6 stationsin the vicinity of the discharge plume. The values of these parameters werereported in the quarterly NPDES reports. Allvalues were within expected levels.

Nearshore wave conditions were monitored offshore of DCPP. Significant waveheights and peak periods for each six-hour period and joint frequency distributionof wave height and period were calculated. This information was recorded in thedaily onsite weather records. Wave activity was normal compared to previousyears.

Temperatures were continuously monitored at 14 intertidal stations and 14 subtidalstations in the vicinity of DCPP and were reported in the TEMP Report. Alltemperatures were within expected ranges.

2.2 TERRESTRIAL ISSUES (EPP 2.2)

2.2.1 Er i n ntrol PP 2 2 1

Approximately 31 acres south of the Diablo-Midway 500 kV line (Port San LuisQuad - 7.5 min.) and 10 acres one mile east of DCPP near the 500 kV switchyardwere seeded with an erosion control grass seed mixture. This seeding was part ofan ongoing fire fuels management program that includes prescription burns ofvegetation and hand removal.

Erosion control measures implemented at DCPP for the outlying yard and buildingareas included:

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1. The installation of curbs along roadways and drainage ditches to intercept and

direct stormwater run-off away from cut and fillslopes.

2. The placement of rip rap on localized areas of slopes.

3. The installation of a synthetic liner on creek banks to minimize natural erosion.

4. The installation of temporary drainage measures, until permanent repairs arecompleted, where slopes or drainage ditches have been damaged by rain.

5. The application of jute and hydroseeding or the application of gunite to localizedareas of cut and fillslopes.

2.2.2 Her ici e A li i n PP421

During 1991, 4.5 gallons of Monsanto Expedite Grass and Weed (RegistrationNumber 524-432-AA) and 80 pounds Elanco Spike 5G(Registration Number 1471-103-AA) were applied along 6.5 acres of transmission line corridors. Herbicideapplications were performed by Arbor Tree Surgery.

Weed Works Pest Control performed the following herbicide applications within theplant site boundary during 1991.

oA L~AN P~~)f ~ AC Z ~HISept. Hillside by

500 kV yardsRoundup 524-308 5 2.0 qt/acre

Sept.

Oct.

Ranch

Hillsidebehind fueltanks

Roundup

Roundup

524-308

524-308

3 2.0 qt/acre

6 2.0 qt/acre

Oct.

Nov.

Allplant

Road sides,parking lots,230 & 500 kvyards

Oust*

Karmex*

352-401

352-247

48 3.5 oz/acre

57 2.5 lb/acre

Dec. Hillside by Oust500 kV yard 2,4-D*

352-40134704-5

14 3.5 oz/acre6 2.0 qt/acre

* Roundup is manufactured by Monsanto.Oust and Karmex are manufactured by DuPont.2,4-D (Amine 4) is manufactured by Platte Chemical.

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~ s

2.2.3 Pr rv i n f Arch l i 1Re rce~PP 4 2 2

A. CA-SLO-2 Site Management

Activities within the CA-SLO-2 site during 1991 included washing an insulatorstring on a 230 kV tower within the SLO-2 area. Work involved driving a truckoffan established roadway to the base of the tower and washing the insulators.This work was performed on September 29, 1991.

On October 10, 1991, annual photo-monitoring of CA-SLO-2 was conducted by aPG&E archeologist. The photo-monitoring of the 23 stations was performed inaccordance with the Cultural Resources Management Procedures. No significanterosion or site alterations were noted,

B. Chumash Indian Visits and Correspondence

PG&E received the following correspondence during 1991:

1. The signed MEMORANDUMOF AGREEMENT FOR ACCESS TOARCHAEOLOGICALSITE CA-SLO-2 from the Northern Chumash Councilon June 25, 1991. (This was in addition to the "Chumash SLO-2 AccessAgreement" concluded on September 18, 1982, between the Santa Ynez Bandof Mission Indians and PG&E.)

2. The Northern Chumash Speaker's site access request for the fourth annualWinter Solstice Ceremony. (Dated December 11, 1991)

3. The list of attendees for the 1991 Winter Solstice Ceremony from theNorthern Chumash Council: (Received on December 17 and 19, 1991)

The following visits to the SLO-2 site were made by the Northern ChumashIndians during 1991:

1. The speaker for the Northern Chumash Council visited SLO-2 onDecember 13, 1991, to prepare for the Winter Solstice Ceremony.

2. The Chumash Indians visited SLO-2 on December 21 and 22, when theWinter Solstice Ceremony was held.

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S AL OR IMPORTANTENVIR NMENTALEVENTS PP 4.1

No occurrence of an unusual or important event that would indicate or could result in asignificant environmental impact causally related to station operations occurred in 1991.

Environmental studies have been performed at DCPP since 1966. Results of these studiesare tracked to identify unusual or important environmental events. Results of many of these

monitoring studies were published by PG&E's Technical and Ecological Services (TES) inreports entitled, "Environmental Investigations at Diablo Canyon," Copies of these reportsare available upon request.

Monitoring of endangered species conducted in 1991 is summarized in the following sections.

3.1 PEREGRINE FALCON

The two peregrine falcons nesting on Diablo Rock produced one clutch of eggs thatwere removed for incubation at the Predatory Bird Research Group facility inSanta Cruz. Two dummy eggs were placed in the nest until the end of the incubationperiod when a foster chick was temporarily placed in the nest to hold the adults inbreeding condition. The foster chick was replaced with two incubated Peregrine falconchicks on April26, which were immediately accepted by the parents. Both youngbirds were successfully fledged on May 27.

3.2 SOUTHERN SEA OTTER

Sea otters were observed and recorded two times per month from January throughDecember. The core population has remained stable at about 62 individuals. Femalesand pups continue to dominate, representing about 90 percent of the residentpopulation. There are now 20 sea otter haulout sites under observation in the studyarea. Two of these are in the Intake Cove. Within the otter study area, purple sea

urchin densities increased slightly to 1 per 10 square meters. Red sea urchins remainbelow detectable levels. Red abalone abundance decreased to 1 per 300 square meters.

3.3 CALIFORNIAGRAY WHALE

The California Gray Whale was monitored three times per week during the migrationperiod. Whale observations began on January 14, 1991, and the last north boundwhales were observed on May 2, 1991. While the migration began late again thisyear, general abundance and migration patterns were comparable to previous years.

3.4 BROWN PELICAN

Brown pelicans were monitored three times a week from February 13 to December 31,1991. During this period, 26, 172 pelicans were observed. Of these, 5,154 werejuveniles, 4,846 were adults, and 16, 172 were of unidentified maturity. During themonitoring period, there was no detectable difference in the numbers of pelicans flying

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north or south. During this first year of monitoring, there were no indications of anydecrease in population.

3.5 ELEPHANT SEAL

Elephant seals were monitored from January 2 to December 31, 1991. During thespring haulout period, seals arrived on March 26 and departed on June 19. During thisperiod, a maximum of 24 seals were counted and the mean was 6.5. During the fallhaulout period, the arrival date was August 6 and the departure date was January 3,1992. During this period, a maximum of 51 seals were counted and the mean was20.6. Allobserved animals were two years old or younger. Elephant seal abundancehas increased compared to 1990 levels.

4 PLANT ONSISTEN Y RE UIREMENT PP

4.1 DESIGN CHANGES [EPP 3.1, 5.4.1(b)]

No 1991 design changes, tests, or procedures were considered to have involved anunreviewed environmental question as determined by the Plant Staff ReviewCommittee. Thirteen design changes were considered to have the potential to affect theenvironment. A summary of the environmental evaluations for each of the DesignChange Packages (DCPs) is presented below:

DCP-C-41484 This DCP provided for repair of a drainage ditch below parking lot ¹l.The ditch had some associated erosion. The ditch was enlarged and realigned. Thishad a positive effect on the environment by alleviating some slope failure resultingfrom ditch overflow.

DCP-M-43207 This DCP provided modification to controls at the Wastewater Holdingand Treatment facility. These modifications improved control over discharges andminimized potential component failure. The modifications could have a positive effecton the environment.

DCP-A-43263 This DCP provided for the building of a materials testing facility.Since solvents would be used in the facility, the resulting impact on the environmentwas evaluated. It was determined that the small amount of solvents to be used at thefacility would not pose a significant impact to the environment. The AirPollutionControl District was contacted and an exemption from a permit for construction andoperation of this facility was granted on October 23, 1989.

DCP-M-43429 This DCP provided a fresh water connection to the Auxiliary SaltWater (ASW) system so that the ASW could be laid up with fresh water to removemussels from the system, The 40,000 gallons of fresh water would then be dischargedto Diablo Cove. This discharge would be infrequent and insignificant when comparedto storm water runoff into the Cove. This action was reviewed by the CCRWQCB andincorporated into DCPP's NPDES permit (Order 90-09).

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DCP-N-45103DCP-N-46103 These DCPs eliminated potentially unmonitored floor drains from theRadiological Controlled Area and rerouted any liquids to other existing floor drains thatare monitored. The environmental impact is positive as it eliminates potential forunmonitored leak paths.

DCP-M-45274DCP-M-45275DCP-M-45469DCP-M-46275DCP-M-46278 These DCPs provided for replacement of the potassium chromate-basedcorrosion inhibitor with molybdate-based inhibitor in the Intake Cooling Water, ServiceCooling Water, and the Component Cooling Water systems for Units 1 and 2. Thisreplacement of corrosion inhibitor will reduce the severity of any future accidentalrelease to the environment. Thus, the action has a positive effect on the environment.The CCRWQCB concurred with this change and the use of a molybdate-based inhibitorwas included in the NPDES permit (Order 90-09).

DCP-N-45839 This DCP provided for installation of a hypochlorite treatment systemat the plant cooling water intake. Low levels of residual chlorine willbe intermittentlydischarged, but the NPDES permit allows such discharge, and the controls and limitspreviously in effect remain unchanged.

DCP-M-45826 This DCP provided an alternate main steam line drain which wouldchange the discharge pathway from that described in the NPDES permit. PG&E sent aletter to the CCRWQCB on February 13, 1991, requesting approval for the reroutingand received approval via a CCRWQCB letter dated April2, 1991.

5 PLANT REP RTIN RE IREME pp5

5.1 EPP NONCOMPLIANCE

There were no EPP noncompliances during 1991.

5.2 CHANGES IN STATION DESIGN

None of the changes in plant design or operation, or performance of tests orexperiments involved an unreviewed environmental issue or a change to the EPP asdetermined by the Plant Staff Review Committee.

5.3 NONROUTINE REPORTS

There were no nonroutine reports during 1991.

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P*

6 'PPA DIT PP 1

The PG&E Quality Assurance Department performs an audit of the implementation of theEPP each year. The audit of EPP implementation during 1991 was performed duringFebruary 1992 (Audit 92004$ . This audit was performed in accordance with Section 5.1 ofthe EPP. The results of the audit indicated that the plant is meeting the requirements of theEPP and its associated documents. Results of the audit are available for inspection.

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