ML20030C990
| ML20030C990 | |
| Person / Time | |
|---|---|
| Site: | Humboldt Bay |
| Issue date: | 06/10/1981 |
| From: | Brownrigg D, Cayot R, Szalinski P PACIFIC GAS & ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML20030C985 | List: |
| References | |
| 420-81.93, NUDOCS 8108310237 | |
| Download: ML20030C990 (21) | |
Text
'.. -
Report Issued: JUN 10198)
Report 420-81.93 PACIFIC GAS AND ELECTRIC COMPANY DEPARTNENT OF ENGINEERING RESEARCH REPORT NO. 80 ENVIRONMENTAL RADIATION STUDY IN THE VICINITY OF l
HUMBOLDT BAY POWER PLANT l
EUREKA, CALIFORNIA QUARTER ENDING MARCH 31, 1981 (WINTER) l l
l
(' '
. '/
R'.F'.CAJ01,' Chief Report ' Prepared By:
D. L. Brownrigg P. A. Szalinski Nuclear related-DLBrownrigg Indexer 8108310237 810827 DR ADOCK 05000 3
Report 420-81.93
~
TABLE OF CONTENTS Page LIST OF TABLES..........................
ii LIST OF FIGURES ii
SUMMARY
~~................
1 INTRODUCTION...........................
1 SAMPLE COLLECTIONS AND ANALYSES I
DISCUSSION OF ANALYTICAL RESULTS.................
2 RELEASES OF GASEOUS RADI0 ACTIVE WASTE 2
l REFERENCES............................
3 APPENDIX.............................
4 l
I i
(
L
Report 420-81.93 LIST OF TABLES Table Page cl.
Samples Collected......................
7 2a. Radioanalysis of Marine Samples...............
8 2b. Radioanalysis of Marine Samples...............
9 3a. Radioanalysis of Terrestrial Samples 10 3b. Radioanalysis of Terrestrial Samples 11 4.
Dosimeter Measurements 12 5.
Film Pack Measureme.ts 13 6.
Air Particulate, Station No. 3, Gross Beta Activity.....
14 7.
Air Par'.culate, Station No. 45, Gross Beta Activity 15 LIST OF FIGURES Figure Page 1.
Station Locations of Environmental Samples 16 2.
Station Locations of Dosimeters and Film Packs 17 3.
Chronological Display of Selected Environmental Measurements 18 l
i ii
Report 420-81.93
SUMMARY
Measurements of radioactivity in marine and terrestrial samples from the environment near the Humboldt Bay Power Plant durirg this quarter generally mmained within the range of preoperational background The maximum integ. ated dose measured was well below the measurements.
r pennissible contribution of 500 mrem / year in unrestricted areas.
Gross beta measurements in air particulate samples which increased starting in the latter part of October continued at higher than nomal levels this quarter. This increase is due to atmospheric nuclear weapons testing conducted by the Peoples Republic of China on October 16, 1980.
INTRODUCTION This is the 80th quarterly report on radiation in the environment near Humboldt Bay Power Plant (HBPP) covering the period January through March 1981. This report contains infomation on the samples collected, methods and results of radiochemical analyses, a discussion of the results, and also infomation about the " Releases cf Gaseous Radioactive Waste" supplied by the Nuclear Plant Operations Department.
Infomation on the release of liquid radioactive waste from HBPP is reported elsewhere.I*
SAWLE COLLECTIONS AND ANALYSES Air particulate filters, 6simeters, film packs, and 14 marine and were c:,ilected for this report in accordance with the terrestrial sample:
2 requirements of the North Coast Regional Water Quality Control Board '
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 l
Appendix.
- 5ee reference page.
l
2 Report 420-81.93 Thirty-nine gross beta analyses, two iodine-131 analyses, and 14 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 persohnel. 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 L:tring the preceding 52-week period, the maximum integrated radiation exposure was measured at Station 16. The total annual exposure at Station 16 was approximately 14.4 mR above background measured at Stations 2 and 5.
Figure 3 is a chronological display of dosimeter and film pack radiation expo:ures rer month at Station 14 and the air particulate activity at Station 3 from January 1977 through this quarter. Reports 37, 55, and 75 contain graphs from previous years.
RELEASES OF GASEOUS RADI0 ACTIVE WASTE The routine releases of gaseous radioactive wastes have been monitored by the air ejector 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 l
modification outage which started in July 1976, continued through this quarter; therefore, airborne releases were insignificant.
~
3 Report 420-81.93 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 dischargs equirements, dated April 8, 1966.
4.
Department of Public Health letter to PGandE, Attn: Mr. P. Matthew, 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 420-81.93 APPENDIX Page Methods of Sample Collection and Analysis 5
Table 1 Samples Collected 7
Table 2a Radioanalysis of Marine-Samples 8
Table 2b Radioanalysis of Marine Samples 9
Table 3a Radioanalysis of Terrestrial Samples 10 Table 3b Radioanalysis of Terrestrial Samples 11 Table 4 Dosimeter Measurements 12 Table 5 Film Pack Measurements 13 Table 6 Air Particulate, Station No. 3, Gross Beta Activity 14 Table 7 Air Particulate, Station No. 45, Gross Beta Activity 15 Figure 1 Station Locations of Environmental Samples 16 Figure 2 Station Locations of Dosimeters and Film Packs 17 Figure 3 Chronological Display of Selected Environmental Measurements 18
5 Report 420-81.93 METHODS OF SAMPLE COLLECTION AND ANALYSIS Marine samples are collected by Humboldt State College Foundation p'crsonnel under the direction of Dr. J. A. Gast. PGandE Humboldt Division personnel collect the remainder of the samples.
Marine and terrestrial samples' 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/l of water solution containing a single radionuclide.
Radiciodine 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 stripped from the resin and after purification is precipitated as cuprous iodide for measurements by beta-gamma coincidence counting. The detection limit attained by this method is typically 0.2 pC1/ 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
l 6
Report 420-81.93 l
standard deviation in the concentration units (Gaussian) is about 12 percent at the 5 ppm level. Using the factor of 830 pCi/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 spectrometer. The limit of detection for this analysis is typically 0.2 pCi/ml of water.
The airborne particulate saglers 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 mailed 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 chanbers 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 Co@any (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-signa error; i.e., the 95 percent confidence level.
i
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TABLE 1 SAMPLES COLLECTED I
Marine Verte-Clams & Other Bottom Terres-
, Air' Dos P Film Station Flora brates Oysters Invert.
Sedim.
trial Partic. meters Packs 1 K. Salmon Picnic Area 2
7 3
2 1742 Wood, Fortuna 7
3 3 Humboldt Hill (HH) Rd 12 7
3 j
4 Wood & K. Eureka 7
3 i
5 Redwood Ave, Arcata 1
7 3
6 Table Bluff & Clough 7
3 7 Col. of the Redwds 7
3 8 Hmbit H1 Rd 7
3 9 Harbor View 6
3 10 B St., Field Lndg 7
3 11 Whittier Ct 7
3 12 Dell Hill Rd, HH 7
3 13 Crab St, Buhne Pt 7
3 7
3
^
14 South Bay School i
15 Eich Rd 7
3 i
16 Bennett Dairy 1
7 3
w 17 Bassford Rd, Ridgewd 7
3 4
18 6418 Elk River Rd 7
3 19 Noe St 7
3 20 3537 Union St 7
3 21 PG&E Well 2, HH Rd 7
3 7
3 22 Sta B - 14th St 23 Harris St. Substa.
7 3
24 PG&E Office, Eureka 7
3 7
3 j
25 Irving Dr 26 Worthington Dr 7
3 27 Berta Road, 6700 7
3 28 Berta Road, 7200 7
3
=
l 29 Vista Rd 7
3 0
30 Burns Dr 7
3 8"
45 Humboldt Substation 13 48 Holgerson Dairy 1
0 55 PG&E Outfall 1
?
56 1000 ft. N Outfall 2
1 3
l 57 1000 ft. S Outfall 2
1 e"
59 Hookton Channel 1
65 Coast Oyster Co.
I
TABLE 2a RADI0 ANALYSIS OF MARINE SAMPLES K40 Act'ivity
~
Gross Beta Potassium in Potassium Gr ss Activity Content Activity Collec-Beta (pC1/g Dry (pCi/g Dry Sample)
(,g gfg (pCi/g Orig.
tion Counting Sta Sample Description Date Date Beta Gamal Dry Sample)
Sample)2j 3,,p,)
j 55 81B19 Sediment 3/
2/16/81 3/27/81 6.97+0.55 5/
2.30 1.90 5.83+0.46 55 Red Algae /
4 (Gigartina agardhii) 55 Red Algae /
4 (Iridaea sp.)
55 Fish 4/
56 81822 Sediment 2/16/81 4/17/81 7.23+0.57 5/
6.14 5.10 6.03+0.48 13.5 2.21+0.16 56 81821 Red Algae 2/16/81 4/22/81 11.8+0.86
-5/
16.3 (Gigartina agardhii) 56 81320 Red Algae 2/16/81 4/22/81 9.93+0.74 5_/
12.9 10.7 1.90+0.14 (Iridaea sp.)
57 81825 Sediment 2/16/81 3/27/81 6.72+0.53 5/
6.56 5.44 5.57+0.44 57 81824 Red Algae 2/16/81 4/22/81 12.1+0.88 5/
14.9 12.4 2.44+0.18 (Gigartina a_gardhii) 57 81823 Red Algae 2/16/81 4/22/81 8.63+0.66 5/
11.8 9.76 1.49+0.11 (Iridaea sp.)
65 81827 Pacific Oyster /
2/16/81 4/17/81 6.08+0.51 5/
7.55 6.27 1.06+0.09 I 3
i (Crassostrea gigas) 59 81826 Gaper C1am /
2/14/81 4/17/81 7.71+0.61 5/
8.14 6.76 1.51+0.12 g 3
(Tresus capex) o a
1/ Activity at time of sampling. Naturally occurring radioisotopes are not reported.
w 7/For K40 activity of 830 pCi/gm natural potassium, 3/ Samples analyzed at DER then sent to State Department of Health.
T/ Samples not available for collection during this quarter.
3/See Table 2b.
f TABLE 2b RADI0 ANALYSIS OF MARINE SAMPLES Gaisna Activity Station Sample Description (pCi/g Dry Sam)1e) j 55 BlB19 Sediment 7Be=0.060+0.')25 137Cs=0.039TO.004 i
1 95Zr=0.017TO.006 95Nb=0.022TO.004 55 81B22 Sediment 137Cs=0.020 0.004 56 81B21 Red Algae 7Be=0.429+0.172 (Gigartina) 103Ru=0.296TO.039 T
l 95Zr=0.361_O.055 56 81B20 Red Algae 103Ru=0,170+0.042 l
(Iridaea) 95Zr=0.16770.059 95Nb=0.329_TO.040 m
i 57 81825 Sediment 137Cs=0.028+0.003 95Zr=0.042TO.009 i
l 95Nb=0.038TO.005 T
l, 54Mn=0.004_D.002 i
57 81024 Red Algae 103Ru=0.266+0.046 i
(Gigartina) 137Cs=0.0297D.016 95Zr=0.301TO.059 95Nb=0.678 0.039 57 81823 Red Algae 103Ru=0.111 +0.027 (Iridaea) 95Zr=0.146TD.029 y
95Nb=0.227TO.024 g
A 65 8iB27 Pacific Oyster 95Nb=0.048_+0.019 E
59 81B26 Gaper Clam 95Nb=0.123+0.028 a,
TABLE 3a RADI0 ANALYSIS OF TERRESTRIAL SAMPLES K40 Activity Potassium Gross W in Potassium Gross Activity Content Activity Collec-Beta (pCi/g Dry Sample)
{,g gjg (pC1/g Orig.
(pCi/g D tion Counting Sta Sample Description Date Date Beta
- Gammal, Dry Sample)
Sample) f Sample) 0.8810.115/
1 81875 Domstic Wated/
3/10/81 4/22/81 10.211.26 1 81817 Soil 2/16/81 4/17/81 7.8910.62 7/
7.72 6.41 6.4510.50 5 81818 Soil 2/17/81 3/27/81 5.6810.46 7/
4.84 4.02 3.8010.31 16 81A37 Milk 6/
1/19/81 2/19/81 8.76+0.65 10.8 8.96 1165+86 El Il 1/23/81 1311=<0.20 48 81A38 Milk 5/
1/19/81 2/18/81 7.01+0.56 7/
8.06 6.69 1141+91 El 5 7
4/
1/24/81 1311 <0.20 1/ Activity at time of sagling. Naturally occurring radioisotopes are not reported.
7/For K40 activity of 830 pCi/gn natural potassium.
3/Sagle is evaporated for beta analysis and distilled for H-3 analysis. H-3 activity less than 0.20 pCi/ml.
T/ Iodine-131 activity, pCi/1., at t1me GT sugling.
}/pCi/1.
g 6/Sagled jointly with the State Department of Health.
g 7/See Table 3b.
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s TABLE 3b RADIDANALYSIS OF TERRESTRIAL SAMPLES Gama Activity Station Sample Description (pci/g Dry Sample) 1 8'.51 7 Soil 7Be=0.727+0.056 103Ru=0.098TO.007 106Ru=0.051TD.029 137Cs=0.131TO.006 95Zr=0.181_TO.014 5
81B18 Soil 103Ru=0.057+0.011 137Cs=0.226TD.011 95Zr=0.15170.017 95Nb=0.218_TO.013 48 81A38 Milk 140La=0!001+0.0006 E'
E
?+
2
?5
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4 TABLE 4 DOSIMETER MEASUREMENTS Period Start:
12/23/80 1/ 6/81 1/21/81 2/ 3/81 2/17/81 3/ 3/81 3/17/81 4/ 1/80 Period End:
1/ 6/81 1/21/81 2/ 3/81 2/17/81 3/ 3/81 3/17/81 3/31/81 3/31/81 Elapsed Time, Days:
14 15 13 14 14 14 14 364 Station Total d Total d Total d Total d Total d Total d Total d Total d 1
3.7 3.8 3.6 3.2 3.5 3.3 3.2 86.4 2
2.0 3.8 2.7 2.2 3.6 3.1 3.4 80.8 3
2.8 3.1 2.7 3.9 2.8 2.8 3.1 78.3 4
2.8 3.3 2.7 3.4 2.7 2.5 2.3 72.0 5
3.5 3.3 2.7 2.7 3.1 2.8 3.5 75.6 6
3.2 4.3 2.4 3.0 3.1 3.2 2.9 75.2 7
2.7 3.7 3.2 3.1 3.6 2.7 2.6 75.2 8
3.0 1/
3.1 2.8 3.2 2.9 3.1 75.4 (50) 64.2 (44) 9 3.3 3.5 1/
3.2 3.2 2.6 3/
10 3.1 4.5 7.9 2.3 2.6 3.0 3.2 73.3 na 11 2.9 4.5 2.0 2.8 3.4 3.4 3.7 78.1 12 2.9 3.0 2.7 2.0 3.0 3.4 3.0 77.2 13 3.1 3.4 2.4 3.2 3.5 1/
2.4 73.7 (50) 14 3.7 3.8 3.3 2.8 3.2 E.5 3.1 87.0 15 3.6 4.5 3.0 3.3 4.7 2.3 3.5 85.4 16 3.6 4.4 3.2 3.6 1/
3.3 3.0 85.5 (48) 17 2.9 3.8 2.7 3.2 3.1 2.6 2.8 73.3 18 3.0 3.5 2.4 3.4 3.3 1/
3.0 76.7 (50) 19 3.6 3.2 2.7 3.0 2.7 3.0 2.7 76.6 20 3.6 4.4 3.2 3.4 3.3 3.1 2.7 83.4 21 3.2 4.0 2.7 2.8 3.0 3.1 3.1 77.2 22 3.2 3.4 3.4 3.0 2.9 3.1 3.0 75.9 (50) 23 3.1 4.2 2.8 3.4 3.1 3.0 2.7 81.4 g
o 24 2.2 4.3 2.5 3.1 2.9 2.5 2.7 72.9 25 1/
3.0 3.0 2.7 2.8 3.0 2.4 71.9 (50)
A 26 3.2 3.0 2.2 3.5 2.8 3.8 3.7 76.2 g
27 3.1 4.4 3.4 3.2 3.2 3.3 1/
85.1 (50) o 28 3.6 3.1 3.3 4.3 3.2 2.7 7.7 78.3 29 3.9 5.1 3.1 1/
3.2 3.2 2.7 75.1 (48)
.w 30 3.2 3.2 3.1 3.3 3.0 2.7 2.9 75.1 J,/Both dosimeters read 0 and/or full scale.
2_/ Weeks of data, if less than 52, 3/ Dosimeters stolen.
13 Report 420-81.93
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i TABLE 6 AIR PARTICULATE STATION NO. 3 GROSS BETA ACTIVITY Sample Volume Collection Counting Number (m**3)
Date Date pC1/m**3 4
81A08 279 1 / 6/81 1 /1 5/81 0.385+0.025 81A19 282 1 /1 3/81 1 /20/81 0.542T0.035 i
81A42 3 31 1/21/81 1/27/81 0.500TO.023 1 /27/81 T
81 A531/
81A74-2 81 2/ 3/81 2/ 9/81 0.152+0.009 i
81A89 2 91 2 /1 0/81 2/23/81 0.469T0.021 81800 282 2/17/81 2/24/81 0.25670.012 81837 289 2/24/81 3/ 3/81 0.348T0.016 l
81854 280 3/ 3/81 3/10/81 0.43270.020 1
81870 283 3/1 0/81 3 /1 7/81 d.429TO.020 81885 288 3/1 7/81 3/23/81 0.326T0.015 81899 284 3/24/81 4/ 2/81 0.46270.030
=
81c35 286 3/31 /81 4/1 5/81 0.22710.015 1/ Air particulate sample lost in transit from field.
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TABLE 7 AIR PARTICULATE STATION NO. 45 GROSS 8 ETA ACTIVITY l
5 ample Volume Collection Counting Number (m**3)
Date Date pCi/m**3 81A09 426 1/ 6/81 1/16/81 0.394+0.025 81A20 415 1/13/81 1/20/81 0.516TO.033 81A43 497 1/21/81 1/27/81 0.408T0.018 81A54 363 1/27/81 2/ 2/81 0.11F0.005 81A75 428 2/ 3/81 2/ 9/81 0.14270.008 81A90 428 2/10/81 2/23/81 l0.39170.018 81801 421 2/17/81 2/25/81
'0.220TO.010 81B38 430 2/24/81 3/ 3/81 0.29F0.014 1
81855 405 3/ 3/81 3/10/81 0.289T0.013 81871 278 3/10/81 3/17/81 0.4760.022 81886 292 3/17/81 3/23/81 0.374T0.017 81000 278 3/24/81 4/ 2/81 0.508T0.033 3
81C36 291 3/31/81 4/13/81 0.21170.013 E3 0
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