ML20058F588
| ML20058F588 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 06/30/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20058F585 | List: |
| References | |
| NUDOCS 8207300585 | |
| Download: ML20058F588 (22) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSION E\\
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.i DESIC::ATzy gyzggy7AL d$ L.W EI ENVIRONMENTAL IMPACT APPRAISAL OF THE STEAM GENERATOR TUBE SLEEVING REPAIR PROGRAM BY THE OFFICE OF NUCLEAR REACTOR REGULATION FOR WISCONSIN ELECTRIC POWER COMPANY FACILITY OPERATING LICENSE NOS. DPR-24 AND DPR-27 FOR POINT BEACH NUCLEAR PLANT UNITS 1 AND 2 DOCKET NOS. 50-266 AND 50-301 8207300585 820630 PDR ADOCK 05000266 0
1.0 Introduction Wisconsin Electric Power Company (WE), by letter application dated July 2, 1981, requested amendments to Facility Operating Licenses DPR-24 and DPR-27 for Point Beach Nuclear Plant Units 1 and 2, respectively, which would authorize WE to operate with steam generator tubes sleeved, rather than plugged, which have degradation exceeding the plugging limit defined by Technical Specification (TS) 15.4.2.A.5(a). WE modified their applica-tion by letter dated October 12, 1981 to obtain a license amendment which would authorize WE to operate with six steam generator tubes sleeved, rather than plugged, which have degradation exceeding the plugging limit as part of a demonstration sleeving program. The NRC staff evaluated the steam generator tube demonstration sleeving program for Point Beach Nuclear Plant Unit 1 and published the results of that evaluation in an October 26, 1982 Safety Evaluation Report and Environmental Impact Appraisal.
l This Environmental Impact Appraisal documents the results of the staff review and evaluation of the environmental and radiological impacts of the full scale steam generator tube sleeving program for Point Beach Units 1 and 2.
Based on its review, the NRC staff finds that the proposed action will not significantly affect the quality of the human environment.
2.0 Background
In the past, Point Beach Nuc~ lear Plant Units 1 and 2 have experienced various corrosion problems in their steam generators. The problems include caustic intergranular attack of the tubes in the crevice region of the tubesheet and phosphate wastage thinning above and usually within 2 inches of the top of the tubesheet. These problems have been more
. severe for Unit 1 than Unit 2 and resulted in the Commission issuing Orders for Modification of License for Unit 1 dated November 30, 1979 as modified by Orders dated January 3, 1980 and April 4, 1980. These orders imposed, among other things, more frequent eddy current inspections, more restrictive steam generator tube leakage rates and operation at reduced primary pressure for Unit 1.
In an effort to find an acceptable fix to the steam generator tube corrosion problem, WE has submitted an application dated July 2, 1981 for a license amendment involving Technical Specification changes which would allow them to repair degraded steam generator tubes by sleeving rather than plugging, where degradation of steam generator tubes had exceeded the plugging limit of 40% nominal wall thickness.
In support of this requested change, the licensee has filed with the NRC staff for its review a Westinghouse Steam Generator Report and Revision 1 to this report containing technical information regarding tube sleeving of the Point Beach Unit Nos. I and 2 steam generators. WE modified its appli-cation of July 2, 1981 by letter dated October 12, 1981 to request interim operation of Unit I with 12 sleeved tubes (no more than six of which have indications of degradation beyond the plugging limit) as a demonstration program until final review of their overall tube sleeving program has been completed. The NRC staff evaluated this demon-stration program and published the results of that evaluation in an October 26, 1981 Safety Evaluation Report and Environmental Impact Appraisal. The NRC staff issued amendment number 56 to Facility Operating License DPR-24 for Point Beach Nuclear Plant Unit No. 1 on November 10,
. 1981 following the Atomic Safety and Licensing Board's decision on the above matter which approved the demonstration sleeving program.
This report contains the NRC staff's evaluation of the environmental and radiological impact of the full scale steam generator tube sleeving program for Point Beach Nuclear Plant Units 1 and 2.
3.0 Scope of Work to be Prepared During the Full Scale Sleeving Program WE has described the scope of work to be performed during the full scale steam generator tube sleeving program to be conducted at Point Beach Nuclear Plant for Units 1 and 2.
This work will include the following major steps:
(1) Sleeves of either one of two different designs will be inserted in steam generator tubes, some of which have indicaticns of varying degrees of degradation. These sleeves will span the degraded regions.
Approximately 2000-2100 tubes per steam generator will be sleeved in Unit 2.
Although WE plans to replace the Unit i steam generators during the Fall 1983 outage, they wish to retain the option to repair Unit 1 tubes by sleeving as necessary and have thus not withdrawn their application to sleeve Unit 1 steam generator tubes 24 The sleeve designs to be used are described in section 3.2 of the Westinghouse Report WCAP-9960 (Proprietary) dated September 1981 as revised February 1982 entitled
" Point Beach Steam Generator Sleeving Report for Wisconsin Electric Power Company" (Sleeving Report).
(2) Mechanical plugs will be removed from some tubes which have been previously plugged prior to sleeving. The mechanical plug removal equipment is described in section 4.1 of the Sleeving Report. Explosive I
l plugs will not be removed from tubes previously plugged, i
(3) Tubes will be prepared for sleeving in accordance with section 4 of the Sleeving Report.
(4) Field installation of sleeves will take place as described in section,
4 of the Sleeving Report.
(5) Steam generator channel head decontamination will,take place prior to sleeving as described in section 8 of the Sleeving Report.
(6) Non-destructive examination of sleeved tubes will be conducted in accordance with section 7 of the Sleeving Report.
4.0 Environmental Impacts of the Demonstration Program The NRC staff has reviewed the radiological and nonradiological environ-mental impacts of the Full Scale Sleeving Program. The NRC staff has identified the radiological environmental impacts of occupational exposure and public radiation exposure as the only measurable environmental impacts of the demonstration program. These impacts are discussed in the following sections.
. Radiological Assessment 4.1 Environmental Significance of Occupational Exposure Wisconsin Electric Power Company (WE) has estimated that the steam generator tube sleeving project for the Point Beach Nuclear Plant, Unit 1 or 2 or both units will require the expenditure of between approximately 1500 and 3000 person-rems.I These colle:tive occupational radiation exposure estimates for the steam generator tabe sleeving project (s) for Unit 1 or 2 of 1500 person-rems and for hath Units 1 and 2 of 3000 person-rems are obtained by l
multiplying the dose estimate of 750 person-rems per steam generator by 2, the number of steam generators per unit and by 4, the number of steam,
generators in both units, respectively.
To determine the relative environmental significance of the estimated maximum occupational dose of 3000 person-rems, comparisons were made with 1) the doses expected from normal operation of nuclear plants, and 2) other non-nuclear risks.
Most of the dose to nuclear plant workers results from external exposure to radiation coming from radioactive materials outside of the body rather th n from internal exposure from inhaled or ingested radioactive materials.
Experience shows that the dose to nuclear plant workers varies from reactor to reactor and from year to year. For environmental-impact purposes, it can be projected by using the experience to date with s
modern PWRs. Recently licensed 1000-MWe PWRs are operated in accordance with the post-1975 regulatory requirements and guidance that place increased emphasis on maintaining occupational exposure at nuclear power plants as low as reasonably achievable (ALARA). These requirements and this guidance are
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outlined primarily in 10 CFR Part 20. Standard Review plan Chapter 12 (NUREG-0800), and Regulatory Guide 8.8, "Information Relevant to Ensuring that Occupational Radiation Exposures at Nuclear Power Stations Will Be As Low As Is Reasonably Acidevable."
WE's proposed implenentation of these recuirenents and guidelines for the steam generator tube sleeving project for the Point Beach Nuclear Plant was reviewed by the NRC Staff, and the results of that review are reported in
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the Staff's Safety Evaluatian Report.
Table 4.1 shows the occupational dose history for Point Beach 1 and 2.
- When there are more than one reactor unit at a plant site (as at Point Beach) the combined occupational dose for all reactor units (e.g., Point Beach Units 1 and 2) can be reported,6 instead of the doses for each separate unit. With 5
the addition of 3000 person-rems for the sleeving project, the average annual dose for the 11. years of dose history at Units 1 and 2 (1970 through 1901) l will be approximately'730 person-rems or an average of 365 person-rems per reactor unit. Occupational exposure estimates were not specifically considered in the Point Beach 1 and 2 FES.7 Table 4.2 sumarizes the annual occupational radiation doses at U.S. commercial nuclear power reactors for the years 1969 through 1980.6 Average collective occupational dose in' formation for 239 PWR reactor years of operation is available for those plants operating between 1974 and 1980.
(The year 1974 was chosen as a starting date because the dose data for years prior to 1974 are primarly from^ reactors with average rated capacities below 500 MWe.) These data indica'te that the average reactor annual collective dose at PWRs has been
-7 about 440 person-rems, with some plants experiencing an average plant life-time annual collective dose to date as high as 1300 person-rems.6,8 These dose averages are based on widely varying yearly doses at PWRs. The wide range of annual collective doses experienced at PWRs in the United States results from a number of factors such as the amount of required maintenance and the amount of reactor operations and inplant surveillance. Although the dose (1300 person-rems) for these particular plants far exceeds the average of 440 person-rems for PWR's, these doses are included in the average and are considered normal deviations from the average, particularly since such maintenance contributes to effective and safe plant operation and since it is carried out with procedures that maintain exposures ALARA. As Table 4.2 shows, the 3000 person-rems estimate for the sleeving project is within the historical range of ooses above the average for a single unit in a year.
We calculate that 3000 person-rems, the occupational dose estimate for the sleeving project, corresponds to a risk of less than one premature fatal cancer in the exposed work force population. We also calculate that 3000 person-rems corresponds to a risk of less than one genetic effect to the ensuing five generations. These risks are based on risk estimators derived in the BEIR I 9
10 Report and WASH-1400 from data for the population as a whole. New infor-U I
mation in the BEIR III Report would lead to an even lower estimated risk for premature fatal cancers. These risks are incremental risks (risks in addition to the nonnal risks of fatal cancers and genetic effects we all face l
continuously). For a population of 1000 these normal risks that are unrelated l
to Point Beach Nuclear Station would be expected to result in about 190 cancer l
deaths and about 60 genetic effects in the existing population (genetic effects l
l are genetic diseases or malformations),
plus about 300 more genetic effects among their descendants.
To make the health risk associated with radiation dose more understandable, risk comparisons can be made with non-n'aclear activities commonly participated in by many individuals. One rem of radiation is numerically comparable to a lifetime mortality risk of about 10-4 Table 4.3 presents the equivalent risk of 10-4 for several common activities -
risks which many people take routinely and consider to be insignificant.
According to WE the average dose to a worker for the sleeving project will be administratively restricted to 2.5 rems.* As Table 4.3 shows, the' lifetime risk from radiation dose for'the average sleeving project worker is smaller than the lifetime risk associated with many common activities.
Another perspective of an occupational risk comes from comparison of occupational mortality risks in the U.S.
One such comparison is shown in Tabl e 4.4.
It indicates that radiation exposure in the work place, as experienced at an average radiation worker exposure rate, results in a relatively low occupational risk.
Some have criticized occupationally related cancer estimates as being overly conservative.I4 However, most experts feel the risk estimates in Table 4.4 relating to occupational exposure to low-LET radiation are also overestimates.
- Mr. Dave Porter, Manager, Nuclear Engineering Section, Wisconsin Electric Power Company, Point Beach Nuclear Plant, provided this information to Mr. Timothy Colburn, Project Manager, U.S. NRC by telephone conversation i
on May 5, 1982.
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9-In the staff's opinion, the comparisons just presented are reasonable ones. The risks of occupational exposures in the range of 0.5 rem per yeir to 5 rem per year do not significantly affect a typical worker's total risk of mortality.
In summary, the staff has drawn the following conclusions regarding occupational radiation dose. WE's estimata of 3000 person-rems for the sleeving project at Point Beach 1 and/or 2 is reasonable. This dose falls within the normal range of annual occupational doses which have been observed in recent years at operating reactors. Although the doses resulting from the steam generator tube sleeving will increase the annual occupational dose average of Point Beach Units 1 and/or 2 to approximately 355 person-rems per unit, this is still well below the 1300 person-rems per unit annual average which is an upper bound dose average of PWRs experiencing high levels of special maintenance work.
- WE has taken appropriate steps to ensure that occupational doses will b: maintained within the limits of 10 CFR Part 20 and ALARA. The additional health risks due to these doses over normal risks are quite small, less than one percent of normal risk to the project work force as a whole. The risk to an average individual in the work force will be lower than the risk incurred from participation in many commonplace activities. The individual risks associated with exposures involved in the sleeving program will be controlled and limited so as not to exceed the limits set forth in i
10 CFR Part 20 for occupational exposure. For the foregoing reasons, the staff concludes that the environmental impact due to occupational exposure will not significantly affect the quality of the human environment.
. 4.2 Public Radiation Exposure The staff has estimated the amount of radioactivity which will be released in liquid and gaseous effluents as a result of the sleeving project.
Those estimates are presented in Table 4.5. These estimates are based on information supplied by WE to the staff concerning the method of decontamination and subsequent treatment of the decontamination solutions. Table 4.5 presents IO I7 18 effluent releases for 1979,1980 and 1981 from Point Beach 1 or 2 and 7
the FES annual average effluent release estimates.
WE will take several steps to minimize releases.I To minimize airborne releases the channel head decontamination process and the surface preparation process will be wet processes, entraining removed material in water. The air from the channel her.d where the work is being performed will be exhausted through the opposite manway using a high efficiency particulate filter to control i
airborne concentrations during channel head wrk. The water from the decontamination process and the surface preparation process will be treated by filters, an evaporator and a demineralizer to minimize liquid releases.
'9 has reviewed WE's estimates of effluent releases for the sleeving The staff project. Those estimates are based on estimating methods acceptable to the staff and actual releases 'from similar cperations at San Onofre 1 and elsewhere.
Based on this review, the staff concludes that WE's estimates are reasonable.
I9 Table 4.5 shows the expected releases from the sleevino oroject are small compared to both the FES estimates and Point Beach's actual annual releases.
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Therefore, on the basis of this comparison alone, we conclude that the offsite environmental impact that may occur during the period of this procedure will be smaller than that which occurs during normal operation.
We have estimated the doses to individual members of the public as well N the population as a whole in the area surrounding Point Beach 1 and 2 based on the radioactive effluents which the staff estimated fcr the sleeving project (summarized in Table 4.5) and on the calculational methods presented 20 21 in Regulatory Guides 1.109
, and 1.113 Using a maximum liquid release source term due to both reactor units.of 8.4 x 10-7 Cf consisting primarily of Co-60 (Table 4.5) we calculated the maximum individual total body dose
- for an adult to be much less than.01 mrem for the operation. This is equivalent to a dose of very much less than a small fraction of 1 percent of the limits of 40 CFR Part 190. The annual limits of 40 CFR Part 190 are 25 millfrems to the total body or any organ except the thyroid and 75 millfrems to the thyroid.
7 The doses to the population of 819,000 within 50 miles was estimated to be less than 3.6 x 10-2 person-mrems to the total body from liquid effluents.
- 0ur calculations (using the LADTAP Computer Program 22) for the maximum individual total body dose for an adult considered the following pathways:
1.
consumption of fish (21 kilograms per year) caught in the discharge area, and 2.
drinking water (730 liters per year) from the discharge area.
A conservative dilution factor of 1 or no dilution was assumed for each of the above two pathways in our evaluation of radiological exposure due to the release of Co-60 from Point Beach I and 2 via liquid effluents which are expected to result from the sleeving project.
The LADTAP II program implements the radiological exposge models described in U.S. NRC Regulatory Guide 1.109 Rev.1 (Appendix A) for radioactivity i
l releases in liquid effluent.
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. The offsite population dose was calculated by multiplying the (offsite) maximum individual total body dose of 4.40 x 10-8 mrem (estimated for the 7 for the liquid release of Co-60) with the projected population of 819,000 year 1985 within 50 miles of Point Beach 1 and 2.
We feel that this is a conservative estimate as the maximum individual dose estimate is overly con-servative and it is very unlikely that an average individual offsite will receive such a dose.
Every year the same population of about 819,000 will receive a cumulative total body dose of more than 81,900 person-rems from the natural background radiation (about 0.1 rem per year)23 in the vicinity of
> Point Beach Units 1 and 2.
Thus, the population total body dose from the sleeving project is less than 4.40 x 10-8 percent of the annual dose due to natural background. On these bases, we conclude that the doses to individuals in unrestricted areas and to the population within 50 miles due to gaseous and liquid effluents from the sleeving demonstration project will not be environmentally significant.
Since we expect no larger radioactive effluents from Point Beach 1 and 2 after the sleeving (over presleeving operation), we conclude that the impact on biota other than man will also be no larger after the sleeving project.
In summary, the radioactive releases resulting from the sleeving project will be less than those due to normal plant operation. These releases are also much less than the estimates presented in the FES. The doses due to these releases are small compared to the limits of 40 CF.R Part 190 and to the annual doses from natural background radiation. Therefore, the radiological impact of the sleeving project will not significantly affect the quality of the human environment.
a r
Radiological Assessment
Conclusions:
Based on our review of the proposed steam generator sleeving project, we have reached the following conclusions which are discussed in greater detail above.
(1) The estimated range of 1500 to 3000 person-rems for the sleeving project is within the expected range of doses incurred at light water power reactors in a year.
(2) The risks to the workers involved in the sleeving project from radiation exposure are no larger than the risks incurred by:
(a) workers in other industrial businesses, and (b) most people, working or not, from canmonplace activities such as driving a car.
f (3) WE has taken appropriate steps to ensure that the occupational dose will be maintained as low as is reasonably achievable and within the ifmits of 10 CFR Part 20.
(4) Offsite doses resulting from the sleeving project will be:
(a) smaller than those incurred during normal operation of Point Beach I and 2, and (b) negligible in comparison to the dose members of the public in the vicinity of Point Beach 1 and 2 receive from natural background radiation.
. I On the basis of the foregoing statements, we conclude that the proposed sleeving project at the Point Beach Nuclear Plant, Unit No. I and/or 2 will not significantly affect the quality of the human environment.
We have reviewed this proposed sleeving project relative to the requirements set forth in 10 CFR Part 51 and the Council of Environmental Quality's Regulations 40 CFR Part 1500. We have determined that the proposed action will not significantly affect the quality of the human environment.
Date:
Principal Contributors:
Tin Mo Jack Nehemias Tim Colburn Tom Cain l
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j TABLE 4.1 l
ANNUAL COLLECTIVE,3 2
OCCUPATIONAL DOSE AT POINT BEACH UNITS
- 1, 2 l
COLLECTIVE OCCUPATIONAL DOSE YEAR (cerson-rems) 1971 164 1972 580 1973 588 1974 295 1975 459 1976 370 1977 429 1978 320 1979 644 1980 5983 1981 596**
- First commercial operation 12/70 (Unit 1),10/72 (Unit 2)
- Calculated by C. Hinson and R. Pedersen, U.S.NRC, RPSr RAB from data sucolied in February 22, l982, memorandum f rom C.W. Fay, Assistant Vice Presidents Wisconsin Electric (WE) to Director of Management and Program Analysis, U.S. NRC in compliance with 10 CFR Part 20, Section 20.407
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TABLE 4.2 ANNUAL OCCUPATIONAL RADIATION DOSES AT6 U.S. COMMERCIAL NUCLEAR POWER REACTORS (person-rems per reactor unit)
PWR BWR Year Average Average Low g
1969 165 195 42 298 1970 684 127 44 1639 1971 307 255 50 768 1972 464 286 61 1032 1973 783 380 85 5262 1974 331 507 71 1430 1975 318 701 21 2022 1976 460 549 58 2648 1977 396 828 87 3142 1978 429 604 48 1621 1979 510 733 31 2140 1980 578 1,136 22 3626 l
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TABLE 4.3 LIFETIME MORTALITY RISKS j3 NUMERICALLY EQUIVALENT TO ONE REM Type of Activity Eouivalent Risk to One Rem Smoking cigarettes 1 carton Drinking wine 66 bottles Automobile driving 6,600 miles Cancercial flying 33,000 miles Canoeing 1.6 days
- Reing a man aged 60 1.8 days f
- Eight hours per day i
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4 TABLE 4.4 I
I OCCUPAT!0.';AL RISKS (Events peTyear per 100.000 workers) j Mining &
All U.S.
Radia tion Quarrying Industries Trade Excosure (1 )
Fatal Accidents 63 14 6
<1 i
Delayed Ef fects J
Actual readily Occasionally not not Observa bl e Observa ble Observa bl e Observable Estimated
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Includes 115-219
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4-6 lethal cancers (2) lethal cancers U)1976 data, from " Accident Facts,1977 Edition,".';ational Safety Council.
( } Estimates from " Toxic Chemicals and Public Protection, A Report to the President by the Toxic Substances Strategy Committee," Council on Environmental Quality, i
Government Printing Of fice, May 1980.
Assuines 20-38", of all cancers are associated with occupation.
l (3) Estimates from BEIR-III,1980, assuming an average radiation worker exposure rate of 0.5 rem /hr; exposure at the limit, 5 rems /yr, would yield an estimate of from 37 to 63 lethal cancers per year per 100,000 workers.
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T ABLE 4.5 R ADI0 ACTIVE EFFLUEt415 IROM Poltei DEAOt UralT 1 OR 2 ERital0 e M f?l_2t_2_.R e ted sLLR1).
s Type of Radioactive WEEstimatesforgeteases FES Est imates of Effluent During Steeving Annual Releases 979 1YSO 1931 (Cil/Re ntor (A.it ggg3
_G a s e ou s tiohle Gases tiegLigibte 4.8(*2)C 3.2(*2) 3.5 ( * /3 5.0 (* 3) lodine F. Part icutat es*
flegligible 1.4(-2) 2.7(-3) 5.5(-3) 1.0(-1) b b
,tJegl ig ibl e 4.0(+2) 3.3(*2) 2.4(*2) d Liquid Hised iission and 4.2 (-7) 1.88-1) 6.38-1) 5.5(-1) 1.0 (
- 1 )
ac t iva t ion pr oduc t s iritlum toegligibte 4.5(*2) 1.8(+2) 3.3(*2) 1.0(*3)
- Radioactive hatf L ives 8 days or more, buelow tower t imit s of d'tectabilit y f or plant instrumentation.
'4.8(+2) means 4.8 m 10'I.
dtio estimate was given in TES, but f ES stated that there vould be low concentrat ions of trit ium in the gaseous eeteeses.
REFERENCES 1.
Point Beach Steam Generator Sleeving Report for Wisconsin Electric Power Company prepared by the Westinghouse Electric Corporation. September 28, 1981 (revised February 1982) and updated information provided by Mr. Dave Porter of WE via phone conversations with NRC project manager, T. Colburn on May 4 and 5,1982.
2.
U.S. Nuclear Regulatory Commission, Code of Federal Regulations,10 CFR Part 20, " Standards For Protection Against Radiation," as of January 1, 1981.
U.S. Government Printing Office, Washington, D.C.
3.
NUREG-0800, " Radiation Protection," in:
" Standard Review Plan," Chapter 12, July 1981 (formerly issued as NUREG-75/087).
4.
U.S. Nuclear Regulatory Commission, Reculatory Guide 8.8, Revision 3, "Information Relevant to Ensuring that Occupational Radiation Exnosures at Nuclear Power Stations Will Be as Low as Is Reasonably Achievable,"
June 1978.
5.
NUREG-0713, Vol.1, Occupational Radiation Exposure at Commercial Nuclear Power Reactors,1979, U.S.N.R.C., March 1981.
6.
NUREG-0713, Vol. 2, Occupational. Radiation Exposure at Commercial Nuclear Power Reactors,1980, U.S.N.R.C., December 1981.
7.
Final Environmental Statement related to ooeration of Point Beach Nuclear Plant Units 1 and 2, United States Atomic Eneray Commission, May 1972.
8.
NUREG-0692, Final Environmental Statement Related to Steam Generator Repair at Surry Power Station, Unit 1, July 1980.
9.
The Effects on Populations of Exposure to Low Levels of Ionizing Radia-tion, "BEIR Report," recort of the Advisory Committee on the Biological Effects of Ionizing Radiations, National Academy of Sciences - National Research Council, November 1972.
10.
WASH-1400, " Reactor Safety Study - An Assessment of Accident Risks in U.S.
Commercial Nuclear Power Plants," U.S.N.R.C., October 1975.
11.
The Effects on Population of Exposures to Low Levels of Ionizing Radiation "BEIR III Report," report of the committee on the Biological Effects of Ionizing Radiations, National Academy of Sciences - National Research Council, 1980.
12.
1979 Cancer Facts and Figures, American Cancer Society.
13.
E. Pochin, "The Acceptance of Risk," British Medical Bulletin 31(3), 1975.
14.
R. Peto, " Distorting the Epidemiology of Cancer, the Need for a More Balanced Overview," Nature 284, 297-300 (March 27, 1980).
15.
C. Miller, Effluent Treatment Systems Branch, U.S.N.R.C., December 8, 1981 Memorandum to Point Beach File, Radiological Assessment Branch, U.S.N.R.C., regarding source term calculations for steam generator tube sleeving operation as described in Reference 1.
16.
Wisconsin Electric Company, Point Beach Nuclear Plant, Unit Nos.1 and 2, Semiannual Monitoring Reports, January 1,1979 through Jur:e 30,1979 and July 1, 1979 through December 31, 1973.
17.
Wisconsin Electric Power Company, Point Beach Nuclear Plant Unit Nos. I and 2, Semiannual Monitoring Reports, January 1980 through June 30, 1980 and July 1, 1980 through December 31, 1980.
18.
Wisconsin Electric Power Company, Point Beach Nuclear Plant Unit Nos.1 and 2, Semiannual Monitoring Reports, January 1981 through June 30, 1981 and July 1,1981 through December 31, 1981.
19.
R.L. Bancart, Effluent Treatment Systems Branch, U.S.N.R.C., April 21, 1982 Memorandum to Point Beach File, Radiological Assessment Branch, U.S.N.R.C., regarding the 1981 effluent release data.
20.
Regulatory Guide 1.109, " Calculation of Annual Doses to Man from Routine Releases of Reactor Effluents for the Purpose of Evaluating Comoliance with 10 CFR Part 50, Appendix I" (Revision 1), U.S.N.R.C., October 1977.
21.
Regulatory Guide 1.113, " Estimating Aquatic Disprsion of Effluents from Accidental and Routine Reactor Releases for the Purpose of Implementing Appendix I," U.S.N.R.C.
22.
User's Manual for LADTAP II " A Computer Program for Calculating Radiation Exposure to Man from Routine Releases of Nuclear Reactor Liquid Effluents."
NUREG/CR-1276, U.S.N.R.C. (May 1980).
23.
NCRP No. 45, " Natural Background Radiation in the United States," National Council on Radiation Protection and Measurements,1975.
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24.
Letter, C. W. Fay, Wisconsin Electric Power Company, to H. R. Denton, j
Director, Office of Nuclear Reactor Regulation dated May 27, 1982.
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