ML20065R895
| ML20065R895 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 12/13/1990 |
| From: | Stolz J Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20065R899 | List: |
| References | |
| NUDOCS 9012190217 | |
| Download: ML20065R895 (4) | |
Text
{{#Wiki_filter:._ 7590-01 UNITED STATES NUCLEAR REGULATORY COMMISSION NORTHEAST NUCLEAR ENERGY COMPANY MI_LLSTONE NUCLEAR POWER STATION UNIT NO 3 DOCKET NO. S0-423 ENVIRONMENTAL ASSESSMENT AND FINDING OF NO SIGNIFICANT IMPACT The U. S. Nuclear Regulatory Commission (the Commission) is considering issuance of a license amendment to Northeast Nucloar Energy Company, et al. (the licensee) for the Millstone Nuclear Power Station, Unit No 3, located at the licensee's site in New London County, Connecticut. ENVIRONMENTAL ASSESSMENT Identification of Proposed Actien: The proposed amendment would modify the Technical Specifications (TS) to allow an increase in the normal containment pressure range; the proposed range is 10.6 psia to 14.0 psia. The current containment pressure range has a lower value of 8.9 psia with a variable upper value, dcpending upon service water temperature, up to approximately 10.6 psia. The Need for the Proposed Action: The license amendment is needed to eliminate the need for supplemental oxygen for workers, to reduce the potential for personnel injury when entering containment due to pressure changes and to permit more expedient entry into the containment for inspection and problem resolution. Assessment: The licensee addressed the environmental impacts of the proposed action in the application dated r bruary 26, 1990 and a supplement dated April 30, e 1990. 9012190217 901213 PDR ADOCK 05000423 C PDR
4 2-The NRC staff has evaluated the effect of the proposed increase in normal containment pressure on post-Loss of Coolant Accident (LOCA), offsite doses. Using the proposed containment leak rates with a full credit allowed for iodine removal by tne containment spray and the assumptions and parameters in Table 15.2 of Millstone Unit 3 Safety Evaluation Report (NUREG-1031 dated July 1984), the staff compted the offsite doses for the Millstone Unit 3 Exclusion Area (EAB) and Low Population Zone (LPZ) boundaries. Tfie computed ofn ite doses are w1tnio the acceptance criteria given in Section 15.7.5 of the \\ Standard Review Plan (SRP) and the exposure guidelines of 10 CFR Part 100, t With regard to normal station effluents, the Hillstone Unit No. 3 containment would still be maintained at a negative pressure of approximately' h 1 psig. Hence, there will be no leakage of airborne radioactivity from the containment during normal power operations. The only potential effect of the changes will be a reduction in the amount of radioactivity released during containment drawdowns (containment pressure redu lon). This results from the reduced time required to draw a 1 psig negative pressure compared to the time required for the current, more negative containment pressure, and the reduced probability of requiring additional drawdowns. This benefit is expected to be-negligible as containment drawdowns currently represent a small percent of normal station effluents. Based upon the above, the licensee concluded, and the NRC staff concurs, that the proposed changes result in a decrease in normal station effluents and computed offsite doses within the acceptance criteria of SRP 15,7.5 and the exposure guidelines of 10 CFR 100. The proposed changes would not affect
.1 any other evaluations as presented in the Final e .vnmental Statement (NUREG-1064 dated December 1984). Therefore, the proposed changes have no negative environmental ir[ pact'. Alternative to the Proposed Action: l It has been concluded that there is no measurable impact associated with j the proposed exemption; any alternatives to the exemption would have either essentially the same or greater environmental impact. ~ Alternative Use of Resources: e This action does not involve the use of any resources different from or beyond the scope of resources used during normal plant operation, which were assessed in the Final Environmental Statement relating to plant operation. Agencies and Persons Consulted: The Comission's staff reviewed the licensee's request that supports the proposed exemption. The staff did not consult other agencies or persons. FINDING OF NO SIGNIFICANT IMPACT Based upon the foregoing environmental assessment, the Comission concludes that the propcsed action will not have a significant effect on the quality of the human environment. Accordingly, the Comission has determined not to prepare an environmental impact statement for the proposed. amendment. For further details with respect to this action, see the request for license amendment dated February 26, 1990 and the supplement dated April 30, 1990. A copy is available for public inspection at the Comission' Public Document Room, the Gelman Building, 2120 L Street, NW, Washington, D.C. 20555,
.m.~ b , -. c 4 and at the. local public document room located at the Learning Resources Center, Thames Valley State Technical College, 574 New London Turnpike, Norwich, - Connecticut 06360. Dated at Rockville, Maryland this 13th day of December 1990. FOR THE NUCLEAR REGULATORY COMMISSION L J n . Stolz, Director ro et Directorate I-i sion of Reactor Projects - I/II Office of Nuclear Reactor Regulation-2- -rvm- -w w a---- ww w w ,,-~w -wv ~ .e- = - -,}}