ML20002D152
| ML20002D152 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point File:Consumers Energy icon.png |
| Issue date: | 09/13/1966 |
| From: | Haeuter R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Boyd R, Morris P US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 8101190548 | |
| Download: ML20002D152 (16) | |
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2Qg.-g '.cn'.gan Avenue. Jacuson, M%nagan 49201 e Area Code S17 788-055 Cn 1 wear u Generai off.c September 13, 1966 Re: Docket 50-155 HileCopy{sugl)
Dr. Pctcr A. Merris, Director Division of Reactor Licensing United States Atomic EnerCy Commission Ucshington, D. C. 20545
Dear Dr. Morris:
Attention:
Mr. Roger S. Boyd In your letter of July 15, 1966, you requested infor-nation on the progran now in effect for monitoring radioactivity in the environnent around our Big Rock Point nuclear Plant. Following is an up-to-date description of the program, arranged in the sa=c order as your specific questions.
You first asked for information on the objectives of the program along with procedures for carrying them out. The objec-tives of the radiological environmental nonitoring progrc= at the Big Rock Point Eucleal Plant are:
(a) To help demonstrate compliance with covernmental regulations which specify radioactive vaste release limits.
(b) To cooperate with the Michi an Departner.t of C
Health and the Michigan Water Resources Commission in maintaining a radiological monitoring network within the State of Michigan.
(c) To provide feedback information from the environ-nent which serves as a check on plant operations.
(d) To provide radiological environ =cntal background information within the framework of a highly variable fallout background
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Dr. Pet:r A. Morris 2
Re: Docket 50-155 September 13, 1966
~
so that in the unlikely event of a significant release of. radioactivity, the environmental effects could be estimated.
The above objectives are extremely difficult to fulfill unless one also includes the monitorinE of the process waste streams in the plant. All radioactive effluents are measured at the plant discharEe point where concentrations are hi hest and hence where E
measurements are most sensitive. Because of the nature and low 1cyc1 of radioactivity of the waste effluents, e.g. noble radiocases, acti-vated corrosion products, etc., it is extremely difficult to detect them in the human food chain or in the environment at any distance from the plant boundaries. The environmental monitoring program for the Big Rock Point Huelcar Plant then, depends primarily on in-plant measurements of radioactivity discharEcs. The field measurements of the environmental monitoring program serve basically as relerence points.
Question:
1.
The number and locations of points where samples of air, water, soils, vegetation, milk, aquatic life, etc., are collected for subsequent laboratory analyses. Describe the procedures followed for obtain-ing these samples, the frequencies of collection, the types and sensitivities of radioactivity measurements made, and designate the laboratories where the measure-ments are performed.
Answer:
Currently, seven environmental monitoring stations are maintained in the area around the plant. At each station, air is continuously drawn through a high efficiency filter which is then counted for gross beta-gamma radioactivity. A separate analysis is also made for iodine - 131. The filters are collected weekly then sent to Cambridge Nuclear Corp.
(Iso-Serve) Cambridge, Massachusetts,
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-- Dr. Pctor A Eorris 3
Re: -Docket 50-155 September-13, 1966.
0 where both of the above analyses are perfor=ed. Approximately 2 x 10 ml-of air constitutes the air sample. Tne sensitivity limit for this measurementis1x'10-13pe/ml.
Initially, in the Big Rock Point environmental monitor-ing progrs=, milk, precipitation, well water, crops in season, grass, fish and henthos were collected at or near the various environmental monitoring stations. 'Cc=posite surface water samples of the circulating
~ vater inlet and discharge were also collected. Tnis sampling was started in late 1960, approximately two years before plant operation. A study of the results of the analyses performed on the grab cre:ples led to their
- discontinuance in December, 1964, en the grounds that they were not sensitive'enough indicators for the environ =catal monitoring program.
' Tne only environmental samples retained were of the integrating type.
7dese were the composite well water samples from the plant site and'nir samples from the 7 stations. Additionally, the composite surface water samples from the circulating water inlet and the discharge canal were retained. Each day a cc=posite sample of the circulating water inlet and discharEc is collected and counted for gross gamma. These samples are evaporated and concentrated and counted on a proporational counter with 2 Ii geometry. Tne sensitivity of the measurement is 2 x 10-9 pe/ml.
Question:
2.
Tne number and locations of points where direct Comma radiation measurements are made. Describe the equip-ment used including the calibration, sensitivity, frequency of measurements, and procedures followed in obtaining these measurcments.
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Dr. Peter A. Morris 15
- Re: Docket 50-155 September 13, 1966
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.Ansucr:
In addition to the' air particulate samples,taken at' 4
1
~ each of the seven environmental monitoring stations, a film packet i'
of East =an Type 3 fib is exposed to measure external gama dose in the environment. Fib packets are also exposed at.10 locations on the plant cite. -Tne fib packets are collected monthly and sent to the Radiation Detection Co=pany, Mountain View, California, who both sup-plies and reads the fi h. Each batch of fih is accompanied by a number of control fiks which are used in the determination of the background external gc=a doce. Tne Eastman Type 3 film has a minimum censitivity of 3 mr with an accurancy of i 3 mr.
The encrcy dependence of the fi'a. is not greater than -10% above 35 Key and not creater than
-25% betvacn 20 and 35 Kev. The calibration of environmental films j
5: perfomed by both Radiation Detection Ccapany and Consumers Power j
Company. Both expose the films from the ecmc batch to a known quantity of radiation. Tne films croosed by Consuncrc Power Co=pany are developed and read by Radiation Detcetion Company who do not know to what 1cycls the fi hs were exposed. Tnis provides a non-biased check on the calibration.
Question:
3 Provide an up-to-date map chowing locations of the monitoring stations enumerated in 1 and 2.
Answer:
Ficurce A and B are maps showing the locations of the i
environmental monitoring stations under the present program. Figure A shows the stations where air samples are tchen along with the environ-mental film. Ficure B shows the locations of the additional environmental films on the plant cito.
1
. Oucation:
1,. Correlation of the results of the environmental.
i monitoring procrc.m with radioactivity emissions.
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~4 Dr. Fcter A. Morris 5
Re: Docket 50-155-
- cptc=ber 13, 1966.
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Results. of enviro =cntal sanpling and condenser circulat-ing water sampling are shown in Figures C.through G.
Ficure C shows results of the film readings at four of i
the stations.
As seen from the Fi ure, the;only station which shows E
any correlation with stack releases is Station No. 1 which is located 1
adjacent to the turbine building in the substation. This film reading l
1s due to cc:. a'shinc from the turbine and stack during operation.
Ho other stations show any correlation with plant operation.
An increasc in the Station No.1 film reading is -noted during the latter part of 1965 which corresponds v3,th operation with known defective fuel in the reactor. Tnis, again, is associated with the ca a shine from the stack. Readingsinthe40-50mr/monthrange were also e:gerienced in early 1966.
f Figure D shows the gross beta-gn=na activity of the-ke inlet and outlet condenser circulating vater.
Figures E, F, and G show the results.of the. environmental air sc.~ples at three locations. Ho correlation of these samples with stack release rates is evident.
Question:
5 Describe any aspect of the monitoring procrs=
l and any special studies being carried out through contractual or cooperative arrancements, j
Answer:
No contractual arrangements exist at this tinc concerning j
environmental studies.
l In Septc=ber 1962, a field test of a new envirc= ental monitoring concept was started. Tnis test consisted of using specially 1.
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packaced. sensitive photocraphic film to nonitor the dose from radioactive nobic cases emitted fro:r. the plant. Tnis test was conducted in coopera-tion.with Dr. G. H. Ehipple, School of Pu'olic Health, University of l.
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'Dr. ?cter A. Mor'ris 6
Re: Docket 50-155 September 13, 1966 Michican, who developed the technique, and Radiation Detection Cc=pany who supplied the specially packaced badccs and a final com=creial packaging concept. This development has become the ca=a monitoring
=cthod in the environmental procram.
At the present time we are testing new dosincters under field conditions in cooperation with Radiation Detection Co=pany.
These dosimeters employ the thermal-luminescent principle and are supplied by Radiation Protection Co=pany. Tnese tests are being con-ducted en an experimental basis.
Cuestion:
6.
Describe any procrcns that have.bcon or are beinc conducted by local, State or Federal acencies (other than AEC) and the vorhing relationships with these croups.
Ansver:
Both the Michican Department of Health and the Michican Unter Resourecs Cc=ission conduct environmental monitorinc procrcr.s.
Tnc Department of Health naintains an air particulate nonitoring station at the plant boundary and various other sites around the State. Tne filters are analyzed for cross beta-ca.ma and iodine-131 activity.
In addition, the Depart =cnt of Ecalth conducts a milh sampling procran which is described in Appendix A.
Tne Water Resources Con =ission conducts an aquatic biota and surface water str.pling procram. Plankton, Alcac, periphyton and crayfish sc=ples are collected semi-annually and analysed for cross beta activity.
Tnere is no direct workinc relationship between Consumers. Pouer Company and the two State aCencies in the environ-ncntal monitorinc procra:a. Tne State acencies prefer it this way.
L l
I Dr.1-4ter A. Moiric 7
Re: Docket 50-155 Septer.ber 13,19M Information is freely exchanced, recults are discucced, accistance in collecting sc=ple or maintaining equipment is civen Vcon asked for, but the Stato agencies feel they must conduct independent procrans.
Yours very truly, g
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.-G =f am u.O R. L. Hauctor Assictan-Electric Production
?2/pch Superintendent - Euclear l
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Table.* Radionuclide eencentaliens in Indi:na milk, Ap june IMS
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('de.wm P.c esium 43 Et rantium-99 St rontium-00
!~i ne 838 Cea.um-13,7 barium-140 -
Famphag (y h teel (pCa/het,3 (pCa/htir)
(go/httr)
(60/but)
(PCe/hter (gG/htsrl locateen j-Apr blay Jun Are blay Jan Ape blay Jun Apr blay Jun Apr 11ay Jun Apr hiny Jun Apr hiny Jun Nor t he ast........
l.01 I.0E f. D I.2101.4101.3 40 0
0-10 14, 13 31 0
20 R.
40 4 '.
0 26 0
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11 Ng N81,2m I.3, Nol e
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0 0
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4s m,
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to 1.io cent al...........
1.33 I.n 1.0s, 1. 8 3, l.W I.340.1.3 v$
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40 80 5%
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- 4. Michigan Milk Network analytical procedure for strontium-90 is based j
January-June 19G3 upon ion exchange methods. Cations are cluted from the ion exchange resin with a sodium l
Division of Occupational Health chloride solution. Subsequently, calcium and t
Michigan Department of #calth strontium are separated using a nitric acid i
method. The strontium is scavenged from i
The Michigan Department of Health began the rare earths and set aside for a 2. week samph.ng pasteurized milk for radionuclide yttrium-90 Ingrowth. The yttrium-90 is then analyses in h.ovember 1962. Under this pro-separated and counted in a low.backgrounu, gram, weekly pasteurized milk sampics are col-beta counter after whien the strontium-90 is 4
lected in the seven major milk producing areas i
calculated' 1
in the State: Charlevoix, Detroit, Grand Rap.
Iodine-131, cesium-137, potassium-40, and ids, Lans.ing, Marquette, Monroe, and Saginaw barium-lanthanum-140 concentrations are (figure 7). Daily samples within each area are i
composited in proportion to sales volume.
Table s. Radionucliden in seven Michican milk I
producing areas, January-June 1965
- j Analytical proccdures The resultant samples are analyzed weekly a f,%,"ih
.u l, 70 8l3"iG $"*
Ct"r**
I for strontium-90, iodine-131, cesium-137, t.
potassium-40, and barium. lanthanum-140. The cha,i,voi :
Ja.ary.................
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<!4 71 4
Febru a ry................
1,3E0 21
<14 72 3
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1.330 21
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<14 144
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5 Febru a ry................
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4 Arnt....................
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January.................
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<te 4s Figure 7. Michigan milk sampling stations
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3 CH Radiological Health Data
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emamaeason0arma=4. a60=04tuava4 somoerwa.daa60= oar =amaaa60=047wam.a 1962 8963 1964 1963 l'e2 l'43 1964 1943 Figure 8. Monthly average concentrations of strontium-90 and cesium-137 in Michigan milk,1962-June 1963 determined by gampia-scintillation spectro-milk for the period January to Jur.c 1965. The metry. The counting system consists of a 4-x results are given for the seven major intilk 4-inch sodium fodide (thallium activated) crys-producing areas in the State.
t'ai detector and a 400-channel pulse-height During this period, iodine-131 and barium-analyzer. The minimum levels of detectability lanthanum-140 concentrations in general re-are as follows: strontium-00,5 pCi/ liter; ces-mained below detectable levels.
fum-137,5 pCi/ liter; iodine-131,14 pCi/ liter; To visualize genercl trends in strontium-00 potassium-40, 80 pCi/ liter; and barium lan-and cesium-137 levels, monthly average con-thanum-140, 4 pCi/ liter, centrations are presented graphically in figure C. Strontium-00 concentrations have remained Results and discussion fairly constant since the beginning of the pro.
gram. Ces.ium-137 concentrations have fol-l Table 8 presents the monthly average radio-lowed a general decreasing trend since the peak nuclide concentrations in Michigan past<.e:azed observed in the summer of 1963.
j November 1903 615 e
6