ML20005B987

Preoperational Environ Radiological Monitoring Program at Fermi-2,Annual Rept 1978.

ML20005B987
Person / Time
Site:	Fermi
Issue date:	02/28/1979
From:	Englehart R, Harr E, Smyth R NUS CORP.
To:
Shared Package
ML20005B986	List: ML20005B985 ML20005B987 ML20005B988 ML20005B989
References
NUS-3346, NUDOCS 8109160255
Download: ML20005B987 (37)

Text

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i NUS-3346 i

PREOPERATIONAL ENVIRONMENTAL RADIOLOGICAL l MONITORING PROGRAM at

$ FERMI-2

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Annual Report

1978 .

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Prepared for The Detroit Edison Company by Ernest C. Harr, Jr.

Randall C. Smyth

February 1979 4

, Northern Environmental Services Division NUS Corporation 4 Research Place Rockville, Maryland 20850 I

k. .w Richard W. Englehart, Ph.D. Roy S. Denham, Manager g

t Project Manager Rockville Office Managar, I 'diological Programs Department Northern Environmental Services j

Q Division l

8109160255 810914 PDR ADOCK 05000341 R PDR

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1 i O rABtE oP CONTENTS Pace I. INTRODUCTION 1 A. Site and Station Description

! B. Objectives and Overview of Fermi-2 Monitoring Program II. PROGRAM DESCRIPTION 4 III. SAMPLING METHODS AND PROCEDURES 12 I

A. Direct Radiation B. Fish C. Shoreline Sediments IV.

SUMMARY

AND DISCUSSION OF 1978 ANALYTICAL RESULTS 14 A. Direct Radiation B. Fish

. C. Shoreline Sediments V. REFERENCES 23 APPENDIX A Deviations in the Sampling and Analytical Regime 24 APPENDIX B Iaboratory Quality Assurance 26 APPENDIX C Analytical Procedures 30 APPENDIX D Reporting of Analytical Results 31

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LIST OF TABLES 1 1 i

Table No. Pace t.

1 Environmental Radiological Monitoring Program 8

Fkst Year - 1978 5 i I ,

, i 2 Environmental Radiological Monitoring Program l Second Year - 1979 6 i

. 6 3 Sample Locations and Associated Media 8

! 4 Direct Radiation - Analytical Results 16 j i

!f', 5 Fish (Perca flavescens) - Analytical Results 18 6 Shoreline Sediments - Analytical Results 20 7 Indicator Location Statistical Evaluation 22

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'/ c 1 1 Sampling Locations - By Station Number '

) (Immediate Vicinity of Fermi-2) 10 )

4 i 2 Sampling Locations - By Station Number

{y (Greater Than 5 Miles) 11 i i t i

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( I. INTRODUCTION l

O g The preoperational radiological environmental monitoring program for Fermi-2 was initiated on March 15, 1978 and will continue until fuel loading, presently f scheduled for June 1980. This program is being conducted by NUS Corporation under contract with The Detroit Edison Company. This is the first Annual I Report for the radiological environmental monitoring program being conducted j under the contract. This report covers the period March 15, 1978 through December 31, 1978 and summarizes the results of measurements and analyses of data obtained from samples collected during this interval.

A. Site and Station Description i

Fermi-2 is a BWR designed to operate at a powei level of about 1150 mega-watts of electrical output with the main condense'r circulating water cooled by two natural draft, wet type, hyperbolic cooling towers. The plant is located on approximately 1120 acres about eight miles east-northeast of Monroe, Michigan; thirty miles southwest of downtown Detroit, Michigan; I

and, twenty-five miles northeast of downtown Toledo, Ohio. Fermi-2, bounded on the east by Lake Erie, is situated in Frenchtown Township

n Monroe County, Michigan.

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B. Objectives and Overview of Fermi-2 Monitoring Program i

United States Nuclear Regulatory Commission (USNRC) regulations require that nuclear power plants be designed, constructed, and operated to keep levels of radioactive material in effluents to unrestricted areas as low as

, reasonably achievable (AIARA) (10 CFR 50.34). To assure that these criteria are met, each license authorizing reactor operation includes technical speci-f fications (10 CFR 50.36a) governing the release of radioactive effluents.

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! In-plant monitoring is utilized to assure that these predetermined release

, limits are not exceeded. However, as a precaution against unexpected

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! and undefined processes which might allow undue accumulatien of radio-activity in any sector of man's environment, a program for monitoring the

, .' plant environs is also included.

The ragulations governing the quantities'of radioactivity in reactor effluents

, allow nuclear power plants to contribute, at most, only a few percent increase above normal background radioactivity. Background levels at any one location are not constant but vary with time as they are influenced by external events such as cosmic ray bombardment, weapons test fallout, and seasonal variations. These levels also can vary spatially within relatively short distances reflecting variation in the geological composition.

Because of these spatial and temporal variations, the radiological surveys of the plant environs are divided into preoperational and operational phases.

The preoperational phase of the program of sampling and measuring radio-Q activity in various media permits a general characterization of the radiation levels and concentrations prevailing prior to plant operation along with an indication of the degree of natural vanation to be expected. The operational phase of the program obtains data which, when considered altng with the data obtained in the preoperational phase, assist in the evaluation of the radiological impact of plant operation.

Implementation of the preoperational monitoring program fulfills the following objectives:

1. Evaluation of procedures, e-quipment and techniques

2. Identification of potentially imp 2rtant pathways to be monitored after the plant is in operarX i

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3. Measurement of background levels and their variations along O 90tentially important pathwere in the area surroundins the plant.

4. Frovides baseline data for statistical comparison with future j operational analytical results.

Sampling locations were selected on the basis of local ecology, meteoro-logy, physical characteristics of the region, and demographic and land use l

features of the site vicinity. The frequency of sampling and duration of the preoperational program follow the guidance outlined in the USNRC Branch I, Technical Position on radiological environmental monitoring as issued by the Radiological Assessment Branch (March,1978).

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During 1978, the period covered by this report, the scope of the program was limited to the measurement of ambient gamme radiation by thermo-luminescent dosimetry and to the determination of gamma emitters in shore-

'O line sediments and fish (Perca flavescens).

i In 1979, the radiological monitor *ng program will be expanded. Additional r analyses included in the regime will consist of the determination of gross I beta and gamma emitters in air particulates; the collection and measurement of gaseous I-131 cn charce 1 cartridges; the measurement of gross beta in l]

drinking water as well as the determination of gamma emitters and tritium

'; in drinking and surface water; and, the determination of I-131 and other gamma emitters in milk.

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i j II . PROGRAM DESCRIPTION O l l Twelve (12) locations within a radius of about 15 miles from the Fermi-2 site were monitored. At seven (7) TLD locations, two therTnoluminescent L

dosimeters were deployed quarterly to obtain ambient background radiation levels . Additionally, six (6) shoreline sediment samples from three (3) locations I

j. and four (4) fish samples from two (2) locations were collected. The number and location of monitoring points were determined by considering the loca-i tions where the highest offsite environmental concentrations have been predicted from plant effluent source terms, site hydrology, and site meteoro-

! logical conditions . Other factors considered were population distribution, ease of access to sampling stations, security and future program integrity.

The Preoperational Environmental Radiological Monitoring Program for Fermi-2 is summarized in Table 1 for the first year (1978) and in Table 2 ,

lg for the second year (1979). Table 3 describes sample locations, associated media, and approximate distance and direction from the site Figures 1 and  ;

2 designate sampling locations by station number.

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Erivtronmental Radioloolcal Monitorino Prooram, Ptrst Year (1978) i Analysis l S mple Medle Station Number & incation Samplinq Prequency lytm Frequency 4

1 Dirsct Radiation 1 Telephone pole # DE6935 II-6 Continuous sampling Quarterly Gamma dose

^

2 Tree at the termination of TLD s changed Brancho Street quarterly (2 TLD s/

3 Tree adjacent to Swan Boat station Club j 4 Site Doundary and Toll Road, Telephone Pole #DE 762 356 C 5 Site Boundary and Toll Road, Telephone Pole #DE56R 776 35 G5 6 Site Boundary and Toll Road, Telephone Pole g 7 Doty Farm,N.Custer Rd.(Control) j Flah 36 Penni-2 discharge Semi-annually Gamma isotopic Semi-annually Yellow Perch (edible portion)

(Perca flavescens) 11 Control in viclntty of Celeron j island -

Shor:ltne 8 Pt. Aux Peaux,110' offshore Sediments (2) siting directly to land-based

)

wa'er tower

9 Fermt-2 dischargo Semi-annually Gamma isotopic Semi-annually ,

t 10- Estral Beach, 300' offshore siting directly to land-based windmill l Simples analyzed in duplicate.

( } Current patterns vary with seasons approximately 50% upstream and 50 % downstream, consequently no " control" is established.

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TABLE 2 Environmental Radioloolcal Monitorino Program, Second Year (1979)

Analysts

, Srmole Media Station Number & Incation Sa_mylino Frequency Type Freopency s

Pith

! Dirtet Radiation Same as first year' Same as first year Same as first year Shoreline Sediments I. Airborne 1 Telephone Pole #DE693511-6 Continuous sampling, Gross beta Weekly -

a) Particulates 4 Site Boundary and Toll Road, change filters weekly following each Tolophono Pole #DE 762' 35 GC filter change 5 Sito Boundary and Toll Road, Telephone Pole #DE 56R 776 3565 7 Doty Farm, Routo #50 (Control) l b) Radiolodine (Same as Particulates) Continuous sampling, Gamma isotopic Weekly g,y j change canisters weekly Iodine-131 following each h canister changs l

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Surface Water 12 Ifnit 1 Raw Lake Water Monthly Gamma Isotopic Monthly Intake Stnicturd 14 Trenton Power ?lant Intake , Trittum Quarterly -

) Structure (Screenhouse #2) composite by i (Control) location Drinking Water 13 Monroe WaterStation Station (3)

Monthly Gross beta Monthly I

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15 Detroit Water Gamma Isotopic Monthly (righting Island) gy Trttlum Quarterly -

] (Control) . composite by location e

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TABLE 2 (continued)  ;

I Analysis Srmolo Media Station Number & Tocation Samplino Frequency

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Type frequency i

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Milk Indicator locations (3) 1. Monthly Gamma isotopic 1. Monthly

2. Semi-monthly when lodine -131 '2. (Semi-monthly animals on pasture when animals on 1

pasture) j 7 Doty Farm (Control) i 1

(1) . Samples analyzed in duplicate

(2) If gross beta in air or water is greater than 10 times the mean

y of control samples for any medium, gamma isotopic analysis performed

on individual samples.

. (3) To be finalized aftcr milch animal census is conducted in Spring 1979.

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TABLE 3 Preoperational Environmental Radiological Monitoring Program, Fermi-2 Sample Locations and Associated Media t

Station Distance from

, Numb er Direction Reactor (Approx.) Description Media

- 1 NE 1. 3 mi. Telephone Pole #DE 6935 H-6 Di ect Radiation Radjoiodine Particulates 2 NNE 1.1 mi. Tree at the termination of Direct Radiation Brancho Street (private residence) 3 N 1.1 mi. Tree adjacent to Swan Direct Radiation Boat Club 4 NNW 0. 6 mi. Site Boundary and Toll Direct Radiation Road, Telephone Pole Radiciodine

1. DE 762 35 GC Particulates 5 NW 0. 6 mi. Site Boundary and Toll Direct Radiation Road, Telephone Pole Radiciodine

1. DE 56R 776 356 G Particulates 6 WNW 0. 6 mi. Site Boundary and Toll Direct Radiation Road, Telephone Pole 7 W 15 mi. Doty Farm, N. Custer Rd. Direct Radiation (Control) Radiciodine Particulates Milk 8 S 0.9 mi. Pt. Aux Peaux,110 ft. off- Sediment shore sighting directly to land based water tower ,

j 9 E 0.2 mi. Fermi-2 discharge Sediment O 10 NE 1.1 mi. tstret Beech, 300 off- Sediment

• shore sighting directly to land based windmill e

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Preoperational Environmental Radiological Monitoring Program, Fermi-2 O samote tc" ti == ead ^==ociated "edia l

! Station Distance from Number D_irection Reactor (Approx.) Direction Media i

I 11 NNE 9.5 mi. Control in vicinity of Perca flavescens Celeron Island 1*

I 12 SSE 0.4 mi. Unit 1 Raw Lake Water Surface Water Intake Structure 13 S 1. 2 mi. Monroe Water Station Drinking Water i 14 NE 13 mi. Trenton Power Plant Intake Surface Water i

Structure (Screenhouse #2)

[ 15 NNE 20 mi. Detroit Water Station ( }

Drinking Water (Fighting Is1and) 0.4 mi. Perca flavescens

'O16 E Fermi-2 discharge (1200 ft. offshore) l Indicator milk sampling locations will be finalized after milch animal census

/' is conducted in Spring,1979.

(2) Access to this location not finalized.

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, III. SAMPLING METHODS AND PROCEDURES To derive meaningful and useful data from the Environmental Radiological Monitoring Program, sampling methods and procedures are required which Will provide samples representative of potential pathways of the area.

During the preoperational phase of the program, ramples are collected and analyzed not only to obtain background radiological levels, but at the same time to acquire experience with the sampling methodology and pro-cedural format dictated by site specific requir(ments.

A. Direc ~'adiation Thermoluminescent dosimeters (TLDs) were used to determine the direct (ambient) radiation levels at seven (7) monitoring points. The locations were selected by ranking the mixed-mode X/Q values. Stations 1 through 6 O ere situeted in the six h19 hest sectors eround the plent site. amon 7, the control, is located approximately 15 miles west of Fermi-2 in the least prevalent wind direction. The selection of the TLD locations follows the guidelines outlined in the USNRC Branch Tecnnical Positic: on Radiolog teal Environmental Monitoring (March,1978). Duplicate dosimeters of CaSO4 :Dy in teflon, obtained from Teledyne Isotopes, were deployed at each location and exchanged on a quarterly basis by an NUS environmental scientist.

To minimize the in-transit dose contribution, the dosimeters were annealed close to the site within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to field placement. Freshly annealed control dosimeters were sent along with the exposed field dosimeters to

, determine the exposura received 1. the dosimeters in transit from the site to readout in Rockville, Maryland, alibrations of the dosimeters were

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performed in April of 1977 and August of 1978 by obtaining accurately known Cs-137 radiation exposures at the National Bureau of Standards. An exposure history of each dosimeter was maintained to determine any significant change in sensitivity as a result of repeated use and annealing, i

B. Fish Because of its importance to both commercial and recreational fishermen, and the predominance of the species in local r aters, yellow perch (Perca flavescens) were collected semiaar.ually for the monitoring program. As described in Table 1, perch were collected from Lake Erie in the vicinity 1

of the Fermi-2 discharge (Station 16) and a control location in the vicinity of Celeron Isw nd (Station 11) approximately nine (9) miles NNE of the plant.

Using a passive collection technique, an experimer -1 gill r.et (mesh O renains from e99toximetelv 0.s to 3.s inches tc 4ecreese size setectivitv) was set at each sampling location by biologists frcm The Detroit Edison Company . The net was retrieved after approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Entrapped, surviving species other than yellow perch were released.

C. Shoreline Sediment s Sediments were collected semiannually from three (3) locations by biologists from The Detroit Edison Company. Samples were taken with a Ponar dredge from the vicinities of Point Au Peaux (Station 8), Fermi-2 discharge (Station 9),

and Estral Beach (Station 10). The locations are shown in Figure 1.

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.._ .. . ~ . . - . . . . _ , . _ . - _-

IV.

SUMMARY

AND DISCUSSION OF 1978 ANALYTICAL RESULTS Summary data of radiological analyses of environmental media from Fermi-2 collected during 1978 are tabulated and discussed below. The procedures and specificatior s followed in the laboratory for these analyses are as required in Section 5.0 of the Environmental Systems Group Quality Assur-ance Manual vf NUS Corporation and are detailed in the NUS Radiological Laboratory Manual " Environmental Mo.titoring and Radiological S vices Procedures / Work Instructions. "

Radiological analyses of environmental media characteristically approach and freqmtly fall below the detection limits of state-of-the-art measure-(

ment methods. '3) The use of "LT" in the data tehles is the equivalent of the less than symbol (<) and is consistent with the !!US Radiological Laboratory practice of data repcrting. The number following the "LT" is a r * ""2' '' " * ' ' = ' ' ' d ** *= " (" ) "

O "2 " " " * * '2" *

• 2 " ^ a a *"-

dix D. NUS analytical methods meet the LLD requirements addressed in Table 2 of the U3NRC Branch Technical Position.

Tables 4 through 6 specify the radioanalytical results for individual samW 3.

A statistical summary of th e 1972 results appears in Table 7 The reported averages are based only on concentrations above the limit of detection.

In Table 7, the fraction (f) of the total number of analyses which were detectable follows in parentheses. Also given in parentheses are the minimum and maximum values of detectable activity during the report period.

l l

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A. Direct Radiation Environmental radiation dose rates determined by thermoluminescent dosi-meters (TLDs) are given in Table 4. Duplicate TLD badges of four read-out areas each were deployed at each location quarterly. The mean values of four readings (corrected individually for response to a known dose and for in-transit exposure) are reported as "a" and "b". The mean of the two dosimeters is estimated to be correct to i two times the standard deviation of eight readings (95"' confidence level).

A statistical summary of the data is included in Table 7. External radiation

, levels in the environs of the Fermi-2 site ranged from 0.12 to 0.23 mR/ day, which extrapolates to 44 to 84 mR/ year. Cakley calculates an ionizing radiation dose equivaient of 88.8 mR/ year for Michigan, including a terrestrial component of 45.6 mR/ year and an ionizing cosmic ray component O of 43.2 mR/yeer. since oekiey s ve1ues represent evereges covering v :de geographical areas, the measured ambient radiation average of 62 mR/ yea; 'or the immediate locale of Fermi-2 may not be inconsistent with Oakley's observations . Significant variations occur between geographical areas as a result of geologic composition and altitude differences. Temporal varia-tions result from changes in cosmic ray intensity, local human activities and factors such as ground cover and soil moisture. Additiona1 data need to be accumulated to insure that the observed values are indeed typical of the local environment.

. 15 i

O O . . O~..- .-

J TABLE 4 .

l

{ ENVIRONMENTAL RADIbLOGICAL MONITORING PROGRAM, FERMI-2 PREOPERATIONAL,1978 4

i DIRECT RADIATION-ANAIXTICAL RESULTS i

i i Sampling ema amma se Rate, mRhay j Quarter Sampling Period Location a b mean 2 x Relative Standard 1 No Data " "" " '

2 3/15/78 to 6/19/78 0.14 0.14 l 1 0.14 9%

] 2' O.15 0.14 0.14 7%

l 3 0.19 0.17 0.18 6%.

4(3) jg 5 0.21 0.21 0.21 4%

i 6 0.15 0.16 0.16 9%

7 0.18 0.17 0.18 4%

3 6/19/78 to 9/26/78 1 0.13 0.12 0.12 7%  !

2 0.16 0.15 0.16 5%

0.16 3 0.15 0.16 6% '

i 4 0.17 0.18 0.18 6%  :

5 0.19 0.19 0.19 4%

6 0.15 0.16 0.16 8%

2 7 0.17 0.18 0.18 4%

1 i 4 9/26/77 to 12/29/78 1 0.13 0.16 0.14 9%

2 0.17 0.18 0.18 9%

3 0.18 0.18 , 6.18 11%

4 0.20 0.18 0.19 7%

1 5 0.23 0.19 0.21 8%

6 0.18 0.18 0.18 10%

\l (1) Calculated from 8 readir.gs 7 0.20 0.19 0.20 10%

j (2) Program started 3/15/78 (3) TLD's vandalized.

.- - _=. .

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O 8. rish The results of gamma analysis performed on yellow perch (Perca flavescens) collected during 1978 are presented in Table 5. A statistical evaluation is given in Table 7 Naturally occuning K-40 constituted the only detectable nuclide acuvity in the flesh portion of the fish. No fission-produced l

radionuclides were identified.

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TABLE 5 ENVIRONMENTAL RADIOLOGICAL MONITORING PROGRAM, PERMI-2 -

PREOPERATIONAL,1978 i

FISli - YELLOW PERCII (Ferca flavescens), EDIBLE PORTION ANALYTICAL RESIILTS j NUS Gamma-Emitting Nuclides, pC1/kg, wet,1 20 Collection Sampling Sample Ouarter Date Location Number K-40 Mn-54 Fe-59 Co-58 Co-60 Zn-65 Cs-134 Cs-137 2 6/21/78 16 9760a 28001400 LT 60 LT100 LT 60 LT 40 LT 80 'LT 70 ' LT 90 i 9760b 34001500 LT 60 LT 90 LT 60 LT 40 LT 90 LT 30 LT 80 mean 31001500 LT 60 LT 90 LT 60 LT 40 LT 90 LT 50 's LT 90

! .3 7/19/78 11 9791a ,35001900 LT 90 LT150 LT 90 LT 60 LT160 LT 50 LT 70 g 9791b t36001800 LT 80 LT120 LT 90 LT 50 LT140 LT 90 LT110 mean 3600+900 LT 90 LT140 LT 90 LT 60 LT150 LT 70 LT 90 l

i i 4 10/16/78 16 9860a 200011200 LT 80 LT220 LT 90 LT 80 LT210 LT 60 LT 80 1

9860b 360011500 LT100 LT210 LT 90 LT 90 LT190 LT100 LT100

] mean 2800+ 1300 LT 90 LT220 LT 90 LT 80 LT200 LT 80 LT 90 t

i j 10/16/78 11 9861a 390011000 LT120 LT220 LT 80 LT 80 LT200 LT 90 LT 80

. 9861b(3) 370011000 LT110 LT230 LT 70 LT 80 LT180 LT 60 LT 60

mean 380011000 LT110 LT230 LT 80 LT 80 LT190 LT 80 LT 70 l

i.

(1) LT = less than (2) No fish obtained on first sampling attempt - See Appendix A j (3) Replicate count

./ .

O i

8 Shoreline Sediments The processes by which radionuclides and stable elements are concentrated in bottom sediments are complex, involving physicochemical interaction in the environment between the various organic and inorganic materials from the watershed. These interactions can proceed by a myriad of steps in which the elements are adsorbed on or displaced from the surfaces of colloidal particles enriched with chelating organic materials. Biological action of bacteria and other benthic organisms also contribute to the con-centration of certain elements and in the acceleration of the sedimentation

, proc es s .

Results of the gamma isotopic analysis of the sediments sampled from the Fermi-2 environment in 1978 are given in Table.,6. The average, fraction of detectables, and range of radionuclide concentrations are summarized O in Table 7 Naturally occurring K-40 is the predominant radionuclide detected in the samples.

Another radionuclide of natural origin, Ra-226, was identified in NUS Sample Number 9858 collected from Station 9 in October. Due to the non-homogeneity typical of sediment samples, the occasional detection of this isotope is not unusual.

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ENVIRONMENTAL RADIOLOGICAL MONITORING PROGRAM, FERMI-2 .

PREOPERATIONAL,1978 i SIIORELINE SEDIMENTS-ANALYTICAL RESULTS NUS Gamma-Emitting Nuclides, pC1/kg, dry, I2a Collection Sampling Sample Ouarter Date Location Number U dauahters Th dauahters K-40 Cs-134 Cs-137 Others 2 6/20/78 8 9757a 150 20 1101 20 11000'15 00 LT 20 III 40110 N . D. (

l 9757b 1701 40 100I 50 1000011100 LT 40 60130 N. D.

mean 1601 30 100 40 110001800 LT 30 50120 N. D.

6/20/78 9 9758a 6201 90 580Il00 1200011600 LT 80 LT 90 N.D.

9758b 5901100 580 I 90 1000011500 LT 90 LT110 N.D.

mean 600Il00 5801100 11000 1600 LT 80 LT100 N.D.

c$

6/20/78 10 9759a 210I 40 1701 30 120001800 LT 30 LT 50 N.D.

9759b 2401 40 170I 50 1200011100 LT 40 LT 80 N.D.

l mean 220I 40 170,I 40 12000t900 LT 40 LT 60 N.D.

I f 4 10/10/78 8 9857a 280I 70 2201 70 980011200 LT 60 LT100 N.D.

9857b 290 70 280 I 60 12000i1400 LT 70 LT120 N.D.

mean 250I 70 250I 60 1100011300 LT 60 LT110 N.D.

j 10/10/78 9 9858a 11001140 840I220 1400011900 LT110 LT150 20001606(3) 9858b 1090I140 890 Il40 LT130 I3) 1700012200 LT110 21001700 mean 1100 160 860 180 1600012000 LT110 LT140 20001600

~

(1) LT = less than j (2) N.D. = Not detected j (3) Ra-226 1

o O o -

TABLE 6 (Continued)

, ENVIRONMENTAL RADIOLOGICAL MONITORING PROGRAM, PERMI-2

, PREOPERATIONAL,1978 SilORELINE SEDIMENTS-ANALYTICAL RESULTS NUS "~" "U **' "'p 1/ g, dm ? 20

Collection Sampling Sample i

Quarter Date Location Number U daughters Th dauahters K-40 Cs-134 Cs-13 7 Others 4 10/10/78 10 9859a 240I 70 330 I 90 1300011400 LT 60 LT 90 N.D.

I 9859b 3201 70 1701 60 1300011400 LT 60 LT140 N.D.

mean 280 70 2501 80 1300011400 LT 60 LT110 N.D.

U I

(1) LT = less than (2) N.D. = Not detected .~

(3) Ra-226 1

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O ~O TABLE 7 Jnilgalpr l location gtatipliqpj Eygluallgo ,

[.n. ytronmental Rad!olmisgLM9aitorino Program Ann _gaifepers Name of racility: [nt!q. oletml (1011,3 Dordet No.10_-J4L tocation of racility: }Lmjes Southwgs_1,o( DettojWhghtgarL(ffeUEht9wGMEg h Reporting Period: Margtt j W978ltgtnyt_IJecemlstr_]W h _ 913.

Iower I.imit All Indicator location with Control Number of Medium or Pathway of (1) locations Ilht hqgt Annua [J4gan tacations Nonroutine Sampled Wpe and Total Number Detection FAcan (f)U) Name Mean (f)II) Mean (f/2) peported (Unit of Measurement) of Analyses Performed (I.I D) Range Distance & Dtruction Range Range Mea surement s

! TLD's , Direct RaJ!ation Garima Dose 40 0.17 (34/34) Tel. Pole 11D05684 776 35C5 0.20(6/6) 0.18 (6/6) 0 I hKAtay) (0.12-0.21) 0.6 mt. NW (Station 5) (0.19-0.23) (0.11-0.20)

Shoreline Sediments Comma Spec 12 pCa skg (dry weight) U daughters 440 (12/12) retmi-2 Discharge

• 850 (4/4) See note 3 0 (150-1100) 0.2 mt. E (Station S) (590-1100) l Th daughters 370(12/12) l'ermi-2 Discharge 720 (4/4) 0 (100-890) 0.2 mt. E (Station 9) (580-890) 40K 12000(12/12) IYrms-2 D6scharge 13000(4/4) 0 (9800-17000) 0,2 Ag. E (Station 9) (10000-17000)

U 134Cs 150 e ll D < TID 137Cs 150 50(2/12) Pt. Aux Peau 50(2/4) 0 (40-60) 0.9 ml. S (Station 8) (40-60) 226Ra 2000(2/I2) termi-2 Discharge 2000 (2/4) 0 (2000-2100) 0.2 ml. E (Station 9) (2000-2100) rash pCl/kg (wet weight) Gamma Spec 8 40K 3000(4/4) rermi-2 Discharge 3000(4/4) 3710(4/4) 0

(?000-3600) 0.4 ml. E (Station 16) (2000-3600) (3500-3900) 54 Mn 130 < Lt.D (LLD <LLD 0 590e 260 < LLD < LID < LLD 0 5800 130 < I.I.D < l.f.D < LLD 0 60Co 130 < LI.D < TID (ILD 0 657n 260 <ILD t I I.D < LLD 0 134Cs 130 < I 1.D < LLD < LLD 0 1170s 130 <ILD < LID < LLD 0 (h t!D = lower IJmit of Detection as defined in the USNRC Branch Techntcal Position on radiologtcal environmeritst nionttoring. Table 2.(March 1978).

(2) Mean and range bases upon detectatale measurementa only.IYection of detectable measurements at specified locations la indicated in per mtheses (O. p ..

a controla le estabiteheJ. v (3) Current patteme very with seasons approntmetely 501r. iiostroom and 507 downstrenm. conemoventiv no

V. REFERENCES l 1. U.S. Nuclear Regulatory Commission,"An Acceptable Radiological Environmental Monitoring Program", Radiological Assessment Branch Technical Position, Mar'.:h 1978 1

2. Oakley, D. C. , " Natural Radiation Exposure in the United States",

ORP/SID 72-1, Office of Radiation Programs, U. S. Environmental Protection Agency, Washington, D. C. , June 1972.

, 3. National Council on Radiation Protection and Measurements,

" Environmental Radiation Measurements",NCRP Report No.50, Washington, D.C. , December 27,1976 9

0 l

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i 23

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ~ -'- '

APPENDIX A Deviations in the Sampling and Analytical Regime i The following deviations in the Fermi-2 monitoring program have been docu-mented by NUS Corporation and transmitted to The Detroit Edison Company during 1978.

A. Direct Radiation The second quarter TLDs, deployed at Station 4 along Toll Road at the site boundary were missing at the end of the exposure period. There was evi-dence of target shooting in the area and, in all probability, the TLDs were -

destroyed in this manner. The third quarter TLDs were deployed as usual at this location and, to date, no further vandalism has occurred.

B. Fish Fish (Perca flavescens) were not collected by Detroit Edison biologists on the first sampling attempt in June at Station 11 (control), criginally located in the vicinity of Edison's Trenton Channel Plant. Due to the swift currents and abundance of detritus suspended in the ambient waters, the net became

" loaded" and was avoided by fish. As a result, the control location was changed to the vicinity of Celeron Island, approximately 9 miles NNE of the Fermi-2 plant sit. . 'erch were successfully collected from this location on July 19, J E. .ne cesults of the gamma isotopic analysis for fish

! collected uom this b .+ on are included in Table 5 under NUS Sample Number 9791.

l Contractual agreements between Detroit Edison and NUS Corporation require that duplicate gamma analyses be performed on fish samples.

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[ 24

.. , - -- . _ _,. --, - . - - - - - - - - - - - - - - - - - - ~ - - - - - - - - - - - - - - - - - - --- -------

W " Duplicate" is defined as separate aliquots of the sample media. Insuffi-cient sample (Perca flavescens) was collected at Station 11 (Celeron Island) by Detroit Edison biologists to yield two (2) individual sample aliquots.

,; Consequently, replicate gamma isotopic analyses were performed on the entire available sample media. This sample is designated as NUS Sample

! Number 9861; the analytical results appear in Tabic 5.

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APPENDIX B Iaboratory Quality Assurance T

i I. Introduction The quality assurance program of the Radiological Laboratoy of NUS is briefly described in this appendix.

Information on each incoming sample is entered in a permanent log book.

A sample number is assigned to each sample at the time of receipt. This sample number uniquely identifies each sample.

Separate laboratory notebooks are used for each major environmental moni-toring program.

s

{~J Laboraton counting instruments are calibrated, using radionuclide standards obtained from the National Bureau of Standards, the EPA, and reliable commercial suppliers, such as Amersham-Searle. Calibration of counting instruments is maintained by regular counting of radioactive reference sourc es . Background counting rates are measured regularly on all counting instruments. Additional performance checks for the gamma-ray scintillation spectrometer include regular checks and adjustment, when j necessary, of energy calibration.

l 1

! Blank samples are processed, with each group of samples analyzed for j specific radion.aclides, using radiochemical separation procedures. Blank ,

l spiked (known quantities of radioactivity added), and replicate samples l

are processed periodically to determine analytical precision and accuracy.

l t

f L.)

l 26

II. Laboratory Analyses for Quality Assurance The quality assurance procedures employed in the conduct of radiological

+

monitoring programs by the Northern Environmental Services Division Radio-logical Laboratory are as required in Section 5.0 of the Environmental Systems Group Quality Assurance Manual and detailed in the NUS Radio-logical Laboratory Manual. These procedures include the requirement for

1) laboratory analysis of samples distributed by appropriate government or other standards-maintaining agencies in a laboratory intercomparison program, 2) analysis of some of the client's environmental samples split with other independent laboratories, and 3) analysis in duplicate of a specified portion of the client's environmental samples.

The results of the QA analyses performed by the NESD Radiological Labora-tory of NUS Corporation in 1978 are given below.

O V

A. Samples Split with Independent Laboratory Aliquots of shoreline sediments collected in October from Stations 8 and 10 were sent to an independent laboratory for gamma analyses. The results of the intercomparison are listed in Table B-1. Considering the low levels of radionuclides present in the samples and the difficulty included in processine; sediment so that replicate, homogeneous portions may be obtained, the agreement between the results is considered good.

B. In-House Duplicate Analyse.c i

l All analytical work for the Fermi-2 program during 1978 was performed in duplicate and has been addressed in Tables 4 through 6.

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27 i

i

- - - - . . . - - = -

f, =

I O c. Environ =eatai Dosimeters i

NUS Corporation has participated .n the second and third International Inter-comparison of Environmental Dosimeters, sponsored by DOE-EML, ORNL, and the University of Texas School of Public Health. Results for both field and laboratory tests deviated lesis than an average of five percent from the 1'

known exposure (laboratory) or average of doses reported (field) for over one hundred sets of submitted dosimeters.

NUS is participating in the Fourth Intercomparison scheduled during the late winter and early spring of 1979.

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,-~ .

(M 's,

- (v) s /

TABLE B-1

• ENVIRONMENTAL RADIOIDGICAL MONITORING PROGRAM, FERMI-2 PREOPERATIONAL,19 78 SIIORET.INE SEDIMEN13 INDEPENDENT LARORATORY GAMMA REStiLTS Collection Sampling Sample amma Itting Nuciths, pMg, 4, I2a Quartry Date Raa_ tic 1 Number 17 timighters Th da atiters K-40 Cs-134 Cs-137 Others III 4 10/10/76 8 9963(9857) N.R.( I 155118 9360I 940 LT 20 II LT 24 N. D.

10/10/78 10 9864(9859) N.R.I I 267127 1180011200 LT 20 LT 2C N.D.

NtiS GAMMA RESULTS NUS Gamma-Emitting Nuclides, pCl/kg, dry,1 2a Collection Sampilng Sample (1)

Quarter Date Inchtlon _ Number tf daughters Th daughters K-40 _ Cs-134 Cs-137 tO Others

• 4 10/10/78 8 9857a 2801 70 220I 70 980011200 L'l 60 LT100 N. D.

9857b 290I 70 280I 60 1200011400 LT 70 LT120 N.D.

mean 2801 70 250I 60 , 1100011300 LT 6C LT110 N.D.

4 10/10/78 'd 9859a 240I 70 3301 90 1300011400 . LT 63 LT 90 N. D.

9859b 3201 70 170I 60 1300011400 LT 60 LT140 N.D.

mean 2801 70 2501 80 1300011400 LT 60 LT110 N. D.

(1) Number in parenthesis Is r orrespondino NUS sample Muplicate)

(2) LT = less than (3) N.R. = Not Reported (4) N. D. t Not Detected

(

I APPENDIX C 1

Analytical Procedures i

! Environmental samples for the Fermi-2 Environmental Radiological Monitoring

Program were collected and analyzed in accordance with procedures described

! in detail in the NUS Laboratory Manual " Environmental Monitoring and Radiological Services Procedures / Work Instructions". These analytical procedures have been adapted from the published analytical methods of the Environmental Measurements Laboratory (EML - formerly HASL), the labora-t tories of the Environmental Protection Agency, and pertinent ASTM pro-c edures .

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, . _ - - ~ _ . _ _ _ _ _ _ _ _ . . _ . . _ . . _ _ . . _ _ _ . _ . . . . _ _ _ . _ _ _ . . - - - - , . . . _ . _ . -

.s e I

(

g APPENDIX D I

I. Reporting of Analytical Results In the tables presenting analytical measurements, the calculated value is 4

1 reported with the two sigma counting error (2a) derived from a statistical analysis of both the sample and background count rates. The precision of the results is influenced by the size of the sample, the background count rate, and the method used to round off the value obtained to reflect the degree of significance of the results. For analytical results obtained from gamma spectral analysis, the precision is also influenced by the composi-tion and concentrations of the radionuclides in the sample, the size of the sample, and the assumptions used in selecting the radionuclides to be quantitatively determined. The two sigma error, for the net counting rate is O i R 2a = 2 fs t

's y I

where R, = sample counting rate Rb = background counting rate t = sample counting time t g= background counting time i

If the measurements on the samples are not statistically significant (i.e.,

the two sigma counting error is equal to or greater than the net measured value), then the radioactivity concentrations in the sample are considered not detected.

O l 31

Results reported as less than "LT" - are below the lower limit of detection

! (LLD) . The LLD is defined as the smallest concentration of radioactive material in a sample that will yield a net count (above system background)

I that will be detected with 95% probability with only 5% probability of falsely l'

concluding that a blank observation represents a "real" signal .

i For a particular measurement system (which may include radiochemical separation):

4.66 s b E x V x 2.22 x Y x exp(- AA t) where LLD is the lower limit. of detection as defined above (as pC1 per unit mass or volume) sbis the standard deviation of th background counting rate s or of the counting rate of a blank sample as nppropriate (as counts per minute)

E is the counting efficiency (as counts per disintegration)

V is the sample size (in units of mass or volume) 2.22 is the number of disintegrations per minute per picucurie Y is the fractional radiochemical yield (when applicable)

Ais the radioactive decay constant for the particular radionuclide at is the elapsed time between sample collection and counting t

l The following are definitions or descriptions of statistical terms used in the reporting and analysis of environmental monitoring results.

! i Precision relates to the reproducibility of measurements within a set, that is, to the scatter or dispersion of a set about its central value.

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!).

32

- . _ ~ . _ . . . . _ - . . _ _ , . _ , _ . . - . . _ . - . , , .- . . . . - r,,

l 6 Measures of the Central Value of a Set. M_e_an Mean) is the sum n

Xg of the values of individual results divided by a (or Average or Arithmetic the number, n, of results in the set. The mean is given by

{ n X = (X3 + X 2 + * *

• X n )/" " X /n i=1 i Measures of Precision with a Set. Standard Deviation _is the square root of the quantity (sum of squares of deviations of individual results from the j mean, divided by one less than the number of results in the set). The standard deviation, s or a, is given * '

n

, o=s= [

i=1 (Xi - X) /(n - 1)

Q Standard deviation has the same units as the measurement. It becomes a more reliable expression of precision as n becomes large. When the measurements are independent and normally distributed, the most useful statistics are the mean for the central value and the standard deviation for the dispersion.

Relative Standard Deviation is the standard deviation expressed as a fraction of the mean s /X. It is sometimes multiplied by 100 and expressed as a percentage.

l Rance is the difference in magnitude between the largest and smallest results in a set. Instead of a single value, the actual limits are sometimes expressed (minimum value - maximum value).

1 l i i

33

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