ML20148P811
| ML20148P811 | |
| Person / Time | |
|---|---|
| Site: | 05000514, 05000515 |
| Issue date: | 11/03/1978 |
| From: | Weller R Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20148P803 | List: |
| References | |
| NUDOCS 7811290046 | |
| Download: ML20148P811 (7) | |
Text
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. 'O UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING ECARD
~
In the latter of )
) Docket Nos. 50-514 f Portlant General Electric ) 50-515 '
)
(Pebble Springs Nuclear Plant, )
Unit Nos. 1 & 2) )
REVISIONS TO NRC STAFF EVALUATION OF LIQUID RADWASTE SYSTEM WITH RESPECT TO APPENDIX 1 0F 10 CFR PART 50 ,'
AND EFFECT ON OVERALL COST-BENEFIT BALANCE by Richard A. Weller [
INTRODUC TION The purt ose of this testimony is to update the previous Staff testimony (July 29, 1976, following transcript page 2864) concerning the evaluation of the liquid radwaste system with respect to Appendix I of 10 CFR Part 50, and determine the effect of this update on the overall cost-benefit balance. This revised testimony reflects a change in the manner of opera-tion of the liquid Dirty Radwaste System (DRS) as described in Section 11.2 of the Febble Spritigs Safety Analysis Report. This change in the manner of operation of the DRS does not affect the NRC Staff evaluation of the gaseous radwaste system with respect to Appendix 1 of 10 CFR Part 50.be-cause the change in manner of operation does not alter the gaseous source ,
d term presented in the previous Appendix I testimony.
s y/
- However, due to the change in the description of the manner of operation of the DRS, the Staff has reassessed the amounts of radioactive material ,
7 811 u 9 0oy6
\ .
expected to be released in liquid effluents to determine if the proposed Pebble Springs luclear Plant, Units 1 and 2, meets the numerical design objectives specified in Sections II.A and D of Appendix I of 10 CFR Part 50.
EVALUATION In ismendment 12 (June 1978) to the PSAR (Section 11.2), the Applicant modified the descriptions of the manner in which the DRS will be operated.
The modification consists of deleting the commitment to fix the setpoint
-6 The monitor's func-of the DRS process radiation monitor at 10 uCi/cc.
tion is to automatically transfer regenerent and ultrasonic resin cleaner waste to the DR3 for processing when the gross radioactivity exceeds the monitor setpoint. As modified, the process monitor setpoint will be allowed to vary within a range which will ensure conformance with the design objectives of Appendix 1 of 10 CFR Part 50, but which will also permit more flexible operation of the plant.
As shown in the Staff testimony concerning the impact of zero liquid release operation on the NEPA cost-benefit balance (June 6, 1978, following transcript page 5189), the plant has the capability of processing all or any desired percentage of secondary system wastes. However, in order to reflect operation of the Pebble Springs Nuclear Plant at limits close to, but below,the design objectives of Appendix I for radioactive material in liquid effluents, the Staff assumed that 50% of the regenerent solutions will be discharged to the coolant reservoir without treatment. This assump-tion is reasonable since the Applicant's only commitment concerning radioactive
'y l
3 material in liquid ef fluents is to meet the design objectives of Appendix I to 10 CFR Part 50. The Applicant has no commitment to recycle waste to the maximum extent practicable. Based on comparisons with similarly designed pressurized water reactors (planned and operating) and the ,
descriptions of the planned mode of operation of the liquid waste treat-l ment systems as described in Section 11.2 of the PSAR, the assumed release of 50% of the regenerent solutions is at the upper limit of the -
range of values which are reasonable or expected. The assumed release of 50% of the regenerent solutions results in a source term (3.8 Ci/yr/ reactor) which is close to the curie limitation (5 Ci/yr/ reactor) %
of the design objective in the Annex to Appendix I, but which allows for flexible operation of the plant.
As shown in Table I, the expected quantity of radioactive materials in ,
liquid effluents from Units 1 and 2 will be less than 5 Ci/yr/ reactor (3.8 Ci/yr/ reactor), excluding tritium and dissolved gases, in conformance with Section A.2 of the Annex to Appendix I of 10 CFR Part 50. Based on .
the total liquid effluents released from Units 1 and 2, the Staff calculated the annual dose or dose commitment to the total body or to any organ of an individual in an unrestricted area from all pathways of (
exposure to be less than 5 mrem, in conformance with Section A.1 of the Annex to Appendix I of 10 CFR Part 50. The calculated doses are shown in Table 2.
x.
The Staff evaluated the potential radiological impact to the estimated population living within a 5?-mile radius of the plant using the revised liquid source term in Table I. As shown in Table 2, the corresponding revised population dose due to operation of Units 1 and 2 is 0.19 man-rem /
y r. This dose is shown to be a small fraction of the estimated population dose (9.5 man-rem /yr) in Table 10.1 of the Final Environmental Statement for the Pebble Springs Nuclear Plant, dated April 1975.
CONCLUSION -
The NRC Staff's reassessment demonstrates that the doses associated with the normal operation of the Pebble Springs Nuclear Plant, Units 1 and 2, meet the design objectives o'Section II. A of Appendix I of 10 CFR Part 50 Further, the expected quantity of radioactive materials released
- in liquid effluents and the cygregate doses meet the design objectives set forth in the Annex to Appendix I. It should be noted that if the ,
aggregate doses meet the per site design objectives of the Annex to Appendix I, then the per reactor design objectives of Section II.A of Appendix I are satisfied.
i Thus, the Applicant's proposed design of Units 1 and 2 satisfies the criteria specified in the Annex to Appendix I and, therefore, meets the requirements of Section II.D of Appendix I of 10 CFR Part 50.
In addition, the Staff's evaluation shows that the revised liquid source term does not result in a dose to the population within 50 miles of the plant which is likely to alter the benefit-cost analysis presented in i Chapter 10 of the FES.
TABLE 1 (Revi sed November 1978)
CALCULATED RELEASES OF RADI0 ACTIVE MATERIALS IN LIQUID EFFLUENTS FROM PEBBLE SPRINGS NUCLEAR PLANT, UNITS 1 & 2 Nuclide Ci/yr/ reactor Nuclide Ci/yr/ reactor Corrosion & Activation Products Fission Products Cr-51 1.6(-2)a Te-125m 2.3(-4)
Mn-54 5.6(-3) Te-127m 2.6(-3) '
Fe-55 2.3(-2) Te-127 2.6(-3)
Fe-59 1.l(-2) Te-129m 1.3(-2)
Co-58 1.9(-1) Te-129 8.7(-3)
Co-60 2.6(-2) 1-130 1.5(-4)
Np-239 1.0(-3) Te-131m 3.8(-4)
Fission Products Te-131 7.0(-5)
Br-83 2.0(-5) I-131 9.4(-1)
Te-132 2.6(-2) 5 l
Rb-86 5.2(-4) 1-132 2.7(-2)
Rb-88 7.0(-5) I-133 7.l(-2)
Sr-89 4.4(-3) 1-134 6.0(-5)
Sr-90 1.5(-4) Cs-134 3.0(-1) ~
Y-90 1.5(-4) 1-135 3.8(-3)
SR-91 3.0(-5) Cs-136 5.7(-2)
Y-91m 2.0(-5) Cs-137 2.3(-1)
Y-91 7.3(-4) Ba-137m 2.2(-1)
Ba-140 1.l(-3)
Zr-95 7.0(04) La-140 1.2(-3)
Nb-95m 1.0(-5)
Nb-95 6.4(-4) Ce-141 5.7(-4)
Mo-99 8.3(-1) Ce-143 2.0(-5) ,
Tc-99m 7.9(-1) Pr-143 2.5(-4) -
Ru-103 4.l(-4) Ce-144 5.6(-4)
Rh-103m 4.l(-4) Pr-144 5.6(-4)
Ru-106 1.4(-4)
Rh-106 1.4(-4) Total (except 3.8 tritium) ,
Tritium 200 a = Exponential notation; 1.5(-2) = 1.5 x 10-2
o -
TABLE 2 (Revised November 1978) -
COMPARISON OF PEBBLE SPRINGS NUCLEAR PLANT, UNIT NOS. 1 AND 2 WITH APPENDIX I TO 10 CFR PART 50, SECTION II.A, (MAY 5, 1975)d AfiD SECTION II.D, ANNEX (SEPTEMBER 4,1975)
Appendix I a Annexb . Calculated Criterion Design Objectives Design Objectives c Doses Liquid Effluents i Dose to total body from all pathways (Adult) 3 mrem /yr/ unit 5 mrem /yr/ site 0.033 mrem /yr/ unit Dose to any organ from all pathways (infant thyroid) 10 mrem /yr/ unit 5 mrem /yr/ site 1.6 mrem /yr/ unit Doses to Population within 50 mileeradius Liquid Effluents Dose to Total Body from all Pathways, Units 1 and 2 0.19 man-rem /yr a
Federal Register V.40, p. 19442, May 5, 1975.
Federal Register V.40, p. 40816, September 4, 1975.
c Design Objectives given on a site basis. Therefore, these design objectives apply to 2 units at the site.
Uf1ITED STATES OF N1 ERICA
- l1UCLEAR REGULATORY C0!1MISS10fl AFFIDAVIT OF R. A. WELLER Richard A. Weller, having been previously sworn in this proceeding, states as follows: ,
- 1. I am a Senior fluclear Engineer in the Effluent Treatment Systems Branch, Office of Nuclear Reactor Regulation. A statement of my pecfessional qualifications has already been filed in this proceeding.
- 2. I have prepared testimony entitled " Revisions to NRC Staff .
Evaluation of Liquid Radwaste System With Respect to Appendix I of Part 50 and Effect on Overall Cost-Benefit Palance", dated November 3; 1978. The statements contained therein are true and correct to the best of my knawledge and belief.
& G< WW ._
Richard A. Well er 4
Subscribed before me this 3rd day of November,1978.
dYLhtC -
Notary Public '
My Commission Expires: O., f,2 /, /98 2.
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