ML20030C988
| ML20030C988 | |
| Person / Time | |
|---|---|
| Site: | Humboldt Bay |
| Issue date: | 04/03/1981 |
| From: | Brownrigg D, Cayot R, Szalinski P PACIFIC GAS & ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML20030C985 | List: |
| References | |
| 420-81.50, NUDOCS 8108310233 | |
| Download: ML20030C988 (19) | |
Text
.
I'#R 3 "33I Report 420-81.50 Report Issued:
PACIFIC GAS AND ELECTRIC COMPANY 4
DEPARTNENT OF ENGINEERING RESEARCH REPORT NO. 79 ENVIRONMENTAL RADIATION STUDY IN THE VICINITY OF HUMBOLDT BAY POWER PLANT EUREKA, CALIFORNIA QUARTER ENDING DECEMBER 31, 1980 (FALL) l 1
R. F. CAY 0T, Chief Report Prepared By:
D. L. Brownrigg i
P. A. Szalinski 8108310233 810821 PDR ADOCK 05000133 R
Report 420-81.50 TABLE OF CONTENTS Page i
.. LIST OF TABLES..........................
ii LIST OF FIGURES 11
SUMMARY
-i................
1 INTRODUCTION...........................
1 SAMPLE COLLECTIONS AND ANALYSES 1
DISCUSSION OF ANALYTICAL RESULTS.................
2 RELEASES OF GASEOUS RADI0 ACTIVE WASTE 2
REFERENCES............................
3 APPENDIX.............................
4 i
Report 420-81.50 LIST OF TABLES Table Page 1.
Samples Collected......................
7 2.
Radioanalysis of Marine Samples...............
8 3.
Radioan-lysis of Terrestrial-Samples 9
4.
Dosimeter Measurements 10 5.
Film Pack Measurements 11 6.
Air Particulate, Station No. 3, Gross Beta Activity.....
12 7.
Air Particulate, Station No. 45, Gross Beta Activity 13 LIST OF FIGURES Figure Page 1.
Station Locations of Environmental Samples 14 2.
Station Locations of Dosimeters ar,d Film Packs 15 3.
Chronological Display of Selected Environmental Measurements 16 I
11
,. -, ~,,
Report 420-81.50
SUMMARY
Measurements of radioactivity in marine and terrestrial samples from the environment near the Humboldt Bay Power Plant during this quarter generally remained within the range of preoperational background measurements. The maximum integrated dose measured was well below the permissible contribution of 500 mrem / year in unrestricted areas.
Gross beta measurements in air particulate samples increased starting in the latter part of October. This increase is due to atmospheric nuclear weapons testing conducted by the Peoples Republic of China on October 16, 1980.
INTRODUCTION This is the 70th quarterly report on radiation in the environment near Humboldt Bay Power Plant (HBPP) covering the period September thrcugh l
December 1980. This report contains information on the samples collected, methods and results of radiochemical analyses, a discussion of the results, and also information about the " Releases of Gaseous Radioactive Waste" supplied by the Department of Steam Generation.
Information on the release of liquid radioactive waste from HBPP is reported elsewhere.l*
1 SAMPLE COLLECTIONS AND ANALYSES Air particulate filters, dosimeters, film packs, and 15 marine and l
terrestrial samples were collected for this report in accordance with the requirements of the North Coast Regional Water Quality Control Board,3 2
and the Department of Health.4 A table of the samples collected and maps showing the sampling locations (Figures 1 and 2) are presented in the Appendix.
i
- 5ee reference page.
l
2 Report 420-81.50 Forty-one gross beta analyses, two iodine-131 analyses, and 15 gamma isotopic analyses were performed for this report. The results are tabulated in the Appendix. All samples except the dosimeters and film packs were analyzed at the Department of Engineering Research (DER).
Dosimeters were read by HBPP personnel.
Film packs were read by outside contractors.
DISCUSSION OF ANALYTICAL RESULTS The environmental samples analyzed for this report contained, in general, radioactivity concentration levels comparable to preoperational activity levels of similar samples.5 During the preceding 52-week period, the maximum integrated radiation exposure was measured at Station 27. The total annual exposure at Station 27 was approximately 17.0 mR above background measured at Stations 2 and 5.
Figure 3 is a chronological display of dosimeter and film pack radiation exposures per month at Station 14 and the air particulate activity at Station 3 from January 1976 through this quarter. Reports 37, 55, and 75 contain graphs from previous years.
RELEASES OF GASE0US RADI0 ACTIVE WASTE The routine releases of gaseous radioactive wastes have been monitored by the air e!,ector off-gas and stack-gas monitoring systems.
The calibration of these monitors for noble and activated gases has been checked by periodic analyses of " grab" samples on a multichannel gamma scintillation spectrometer. The refueling, maintenance, and station modification outage which started in July 1976, continued through this quarter; therefore, airborne releases were insignificant.
p l
3 Report 420-81.50 REFERENCES 1.
Quarterly report to Regional Water Quality Control Board on Liquid Waste Discharge from Humboldt Bay Power Plant.
2.
Letter from North Coastal Regional Water Quality Control Board to PGandE, Attn:
F. F. Mautz, concerning modifications to waste discharge and environmental radiation monitoring requirements, dated May 7, 1965.
3.
Letter from North Coastal Regional Water Quality Control Board to PGandE, Attn: Mr. P. Matthew, concerning modifications to waste discharge requirements, dated April 8, 1966.
4.
Department of Public Health letter to PGandE, Attn: Mr. P. Metthew, concerning modifications to environmental radiation monitoring requirements, dated June 17, 1966.
5.
Environmental Radiation in the Vicinity of Humboldt Bay Power Plant, Reports 1-8.
6.
Code of Federal Regulations, Title 10, Para. 20.105.
4 Report 420-81.50 APPENDIX Page
. Methods of, Sample Collection and Analysis 5
Table 1 Samples Collected 7
Table 2 Radioanalysis of Marine-Samples 8
Table 3 Radioanalysis of Terrestrial Samples 9
Table 4 Dosimeter Measurements 10 Table 5 Film Pack Measurements 11 Table 6 Air Particulate, Station No. 3, Gross Beta Activity 12 Table 7 Air Particulate, Station No. 45, Gross Beta Activity 13 Figure 1 Station Locations of Environmental Samples 14 Figure 2 Station Locations of Dosimeters and Film Packs 15 i
Figure 3 Chronological Display of Selected Environmental Measurements 16 l
i
5 Report 420-81.50 METHODS OF SAMPLE COLLECTION AND ANALYSIS Marine samples are collected by Humboldt State College Foundation
, personnel under the direction of Dr. J. A. Gast. PGandE Humboldt Division personnel collect the remainder of the samples.
Marine and terrestrial samp1,es are processed quarterly at DER.
Samples are freeze-dried prior to determining gross beta activity. The gross beta analysis is performed on low background, thin window, gas flow proportional counters; the limit of detectability is about 0.5 pCi/gm of a standard containing K-40. Activities are reported both per gram of the dry and per gram of the original sample.
The freeze-dried samples and domestic water are gamma scanned, using a Ge(Li) detector or an Intrinsic Germanium detector and a multichannel pulse height analyzer. The limit of detectability attained in the gamma scan is typically 5 pCi/1 of water solution containing a single radionuclide.
Padioiodine analyses are performed on milk samples within eight days of collection. Following addition of stable iodine to the raw milk to determine chemical recovery, iodine is separated from the milk by using anion ion exchange resin.
Iodine is stri,pped from the resin and after purification is precipitated as cuprous iodide for measurements by beta-gama coincidence counting. The detection limit attained by this method is typically 0.2 pCi/ liter for I-131.
The potassium content of most of the freeze-dried samples is measured by flame photometry in order to estimate the K-40 contribution to the gross activities. The range of concentrations used is one to ten ppm; the 1 r -..
6 Report 420-81.50 standard deviation in the concentration units (Gaussian) is about 12 percent at the 5 ppm level. Using the factor of 830 pC1/g K, the activity of K-40 in a sample is calculated.
The tritium (H-3) activity in domestic water is determined by analyzing a distilled aliquot of'the sample with a liquid scintillation w.
spectrometer. The limit of detection for this analysis is typically 0.2 pCi/ml of water.
The airborne particulate samplers are located at Stations 3 and 45 (Figure 1).
The constant flow samplers have flow rate in the range of 30 to 40 1pm; an HV-70 filter is used. The filters are collected on a weekly basis and wailed to DER. The filters are counted to determine gross beta activity at least 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after collection to allow for naturally occurring short-lived radionuclides to decay.
Gamma dosimetry is performed with two ion chambers (Victoreen, Model 239) and a film pack located at each of the 30 stations shown in Figure 2.
The ion chambers are read in the field by HBPP personnel on a biweekly basis.
The lower of the two readings is normally reported since the dosimeters normally read high on failure. The Radiation Detection Company (RDC). Sunnyvale, California, supplies and reads the film packs. RDC reports film pack doses relative to " background" at the RDC laboratory, which consistently is 8 mR/ month.
The + term in the following tables is the two-sigma error; i.e., the 95 percent confidence level.
TABLE 1 SAMPLES COLLECTED Marine Verte-Clams & Other Bottom Terres-Air Dosi ' Film Station Flora brates Oysters Invert. Sedim.
trial Partic. meter _s Packs s
1 K. Salmon Picnic Area 2
6 3
2 1742 Wood, Fortuna 6
3 3 Humboldt Hill (HH) Rd 13 6
3 4 Wood & K. Eureka 6
3 5 Redwood Ave, Arcata 1
6 3
6 Table Bluff & Clough 6
3 7 Col, of the Redwds 6
3 8 Hnbit H1 Rd 6
3 9 Harbor View 4
3 10 B St., Field Lndg 6
3 11 Whittier Ct 6
3 12 Bell Hill Rd, HH 6
3 13 Crab St. Buhne Pt 6
3 14 South Bay School 6
3 15 Eich Rd 6
3 16 Bennett Dairy 1
6 3
17 Bassford Rd, Ridgewd 6
3 18 6418 Elk River Rd 6
3 19 Noe St 6
3 20 3537 Union St 6
3 21 PG&E Well 2, HH Rd 6
3 22 Sta B - 14th St 6
3 23 Harris St. Substa.
6 3
~
N PG&E Office, Eureka 6
3 25 Irving Dr 6
3 26 Worthington Dr 6
3 27 Berta Road, 6700 6
3 28 Berta Road, 7200 6
3 29 Vista Rd 6
3 E
30 Burns Dr 6
3 3
45 Humboldt Substation 13 48 Holgerson Dairy 1
3 55 PG&E Outfall 1
1 4,
56 1000 ft. N Outfall 2
1 57 1000 ft 5 Outfall 2
1 8
59 Hookton Channel 1
65 Coast Oyster Co.
I
TABLE 2 RADI0 ANALYSIS OF MARINE SAMPLES K40 Activity Gross Beta Potassium Gross Activity in Potassium i
Content Activity i
Collec-Beta tion Counting
(,g gfg (pC1/gDrff (pC1/g Orig.
(pCi/g Dry Sample)
Sta Sample Description Date Date Beta Gamma-],
Dry Sample)
Sample)-
Sample) 55 80803 Sediment 3/
11/20/80 1/12/81 6.1210.51 137Cs=0.01610.003 2.35 1.95 5.15+0.43 55 RedAlgaeil (Gigartinaagardhii)
I 55 80802 Red Algae 3/
11/20/80 1/28/81 9.9610.73 137Cs=0.032+0.026 12.2 10.1 1.5610.12 l
(Iridaea sp.)
55 Fish 3/,i/
56 80794 Sediment 11/20/80 1/12/81 7.3410.59 137Cs=0.02010.004 6.40 5.31 6.5010.52 56 807 %
Red Algae 11/20/80 2/18/81 10.810.70 59Fe=0.6510.34 14.2 11.8 2.5410.16 l
(Gigartina agardhii)
=
56 80795 Red Algae 11/20/80 1/31/81 9.2510.49 137Cs=0.01710.006 11.4 9.49 1.5610.08 (Iridaea sp.)
57 80799 Sediment 11/20/80 1/12/81 5.8110.49 137Cs=0.01710.003 4.40 3.66 5.1510.43 13.4 11.2 3.4610.22 57 80801 Red Algae 11/20/80 2/ 9/81 11.810.75 (Gigartina agardhii) 80800 Red Al 11/20/80 1/28/81 9.3910.70 10.9 9.04 1.1910.09 57 (Iridaea sp.) gae m
65 80805 Pacific Oyster / 11/19/80 1/28/81 5.5610.46 137Cs=0.01110.006 6.78 5.62 1.0110.08 3
(Crassostrea gigas) 3 59 80804 GaperClam3/
11/20/80 2/ 9/81 6.2410.45 137Cs=0.02310.007 5.80 4.81 1.4810.11 h
(Tresus capex) g; 1/ Activity at time of sampling. Naturally occurring radioisotopes are not reported.
g.
~
2/For K40 activity of 830 pCi/gm natural potassium.
J/ Samples analyzed at DER then sent to State Department of Health.
{/Specimensunavailableforsamplingatthistime.
i 8
TABLE 3 RADI0 ANALYSIS OF TERRESTRIAL SAMPLES Potassium K40 Activity Gross Seta Gross Activity in Potassium L
Collec-Beta Content Activity (pCi/g Dry Sample) tion Counting
(,9gfg (nC1/gDr{j (pCi/gOrig.
Sta Sample Description Date Date Beta __
Gamma-],
Dry Sample)
Sample)-
Sample) 1 80776 DomesticWater/ 11/19/80 1/12/81 11.211.6 3
0.7110.10_/
5 l
1 80797 Soil 11/20/80 1/12/81 7.6110.61 137Cs=0.09410.006 3.71 0.08 7.5110.60
- h i
5 80798 Soil 11/20/80 1/12/81 5.9010.50 137Cs=0.25710.011 5.32 4.42 4.2110.36 16 80681 Milk /
10/21/80 12/ 3/80 7.98+0.62 9.58 7.95 1082+84 /
6 5
j 1/
10/25/80
<0.20 48 80680 Milk /
10/21/80 12/ 3/80 6.32+0.52 8.46 7.02
'052+87/
6 5
l i/
10/26/80
<0.20
=
l 1/ Activity at time of sampling.
Naturally occurring radioisotopes are not repor6ed.
I 2_/For K40 activity of 830 pCi/gm natural potassium.
3/ Sample is evaporated for beta analysis and distilled for H-3 analysis.
H-3 activity less than 0.20 pCi/ml.
- l i/ Iodine-131 activity, pCi/1., at time of sampling.
5/pC1/1.
l 6/Sanpled jointly with the State Department of Health.
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.....s TABLE 4 Report 420-81.50 DOSIMETER MEASUREMENTS Pariod Start:
9/30/80 10/14/80 10/28/80 11/10/80 11/25/80 12/ 9/80 12/26/79 Period End:
10/14/80 iO/28/80 11/10/80 11/25/80 12/ 9/80 12/23/80 12/23/80 Elapsed Time, Days:
14 14 13 15 14 14 363 2/
Station Total d Total d Total d Total mR Total d Total d Total mR 1
3.6 3.4 3.2 3.5 3.1 3.5 87.1 2
3.1 3.5 2.9 3.4 3.8 3.3 80.8 3
2.9 3.5 2.8 3.3 3.2 3.9 75.1 4
2.9 3.0 3.3 3.4 3.3 3.2 67.6 5
2.8 3.2 2.7 3.8 3.3 2.9 65.3 (48) 1 6
3.0 2.2 2.8 1.7 2.8 3.7 78.6 1
7 3.1 3.0 2.7 3.4 3.4 3.4 72.4 8
2.7 2.9 3.1 3.6 3.0 3.6 82.4 9
2.9 3.2 1.7 3/
3/
3.0 68.3 (46) 10 2.7 3.8 3.0 3 70 3 71 3.0 73.7 (50) 11 2.7 3.6 2.7 3.5 3.2 3.6 79.8 12 2.8 3.2 3.0 3.1 2.9 3.9 76.7 13 3.3 3.6 2.2 3.3 3.1 3.8 77.5 (50)
C' 14 2.8 3.4 2.8 3.6 2.8 3.1 87.8 15 3.6 7.4 3.3 3.1 3.0 2.5 79.7 (50) 16 2.4 4.0 3.2 3.7 3.8 3.5 86.9 (50) 17 3.5 2.9 2.6 3.2 2.8 2.1 74.8 18 2.1 3.4 3.3 3.8 3.0 3.2 79.5 19 3.2 2.7 3.2 3.4 3.2 3.7 71.3 (50) 20 3.8 3.5 3.0 4.1 3.3 3.9 78.2 (50) 21 3.4 3.2 2.4 3.8 3.5 3.2 83.0 22 3.9 3.4 2.8 3.6 3.0 3.8 75.0 (50) 23 3.9 2.0 2.4 4.6 3.1 4.3 82.5 (50) 24 3.2 2.8 2.2 3.6
- .2 3.8 73.1
- o 25 2.3 5.0 2.9 2.3 3,0 3.4 76.4 4
26 2.1 1.9 3.3 3.9 2.9 3.1 74.5 8"
27 2.6 2.8 3.4 4.8 3.6 3.6 89.2 (50) 28 3.4 3.2 2.9 3.5 3.3 3.8 74.3 0
29 2.7 3.9 2.8 3.5 2.9 1/
74.3 (50)
?
30 3.3 2.0 3.1 3.6 3.4 175 73.0 5
1]Both dosimeters read 0 and/or full scale.
2/ Weeks of data, if less than 52.
3/ Dosimeters stolen.
11 Report 420-81.50 see oo T
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9 Report 420-81.50 TABLE 6 AIR PARTICULATE STATION NO. 3 GROSS BETA ACTIVITY Sample Volume Collection Counting Number (m**3)
Date Date pC1/m**3 80653 275 10/ 7/80 3/25/81 0.035+0.002 80670 288 10/14/80 10/27/80 0.031Tb.002 80678 284 10/21/80 3/25/81 0.04970.003 80703 295 10/28/80 11/ 4/80 0.073TD.005
!.079T0.005 80721 282 11/ 4/80 11/10/80 0
80738 241 11/10/80 11/19/80 0.214T0.014 80755 323 11/18/80 12/ 1/80 0.112TO.008 80810 267 11/25/80 12/12/80 0.123TD.012 80829 285 12/ 2/80 12/13/80 0.14076.010 80841 281 12/ 9/80 12/16/80 0.152ib.010 80849 284 12/16/80 1/23/81 0.243Tb.011 80879 294 12/23/80 1/ 5/81 0.19076.013 0.223;0.015 80894 286 12/30/80 1/ 7/81 1
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Report 420-81.50 1
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STATION NO. 45 GROSS 8 ETA ACTIVITY Sample Volume Collection Counting Number (m**3)
Date Date_
pC1/m**3 80654 419 10/ 7/80 1/23/81 0.031+0.002 80671 440 10/14/80 10/22/80 0.02870.002 80679 414 10/21/80 1/23/81 0.044T0.002 80704 442 10/28/80 11/ 4/80 0.05770.004 80722 427 11/ 4/80 11/12/80 0.07670.005 80737 370 11/10/80 11/19/80 0.134T0.009 80756 479 11/18/80 12/ 1/80 0.09070.006 80811 395 11/25/80 12/12/80 01095T0.006 80830 432 12/ 2/80 12/15/80 0.'135T0.009 80842 424 12/ 9/80 12/16/80 0.127T0.008 4
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80850 416 12/16/80 1/23/81 0.21070.010 w
80880 431 12/23/80 1/ 5/81 0.16670.011 80895 433 12/30/80 1/ 6/81 0.190T0.012 i
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