ML20249C049

Safety Evaluation Supporting Amend 217 to License DPR-65

ML20249C049
Person / Time
Site:	Millstone
Issue date:	06/22/1998
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20249C044	List: ML20249C043 ML20249C049
References
NUDOCS 9806250227
Download: ML20249C049 (3)

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WAaHlNeToN, D.C. 78006 4001

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SAFETY EVALUATION BY THE OHlCE QE NUCLEAR REACTOR REGULATION RA ATED TO AMENDMENT NO: 217 a

TO FACILITY OPERATING LICENSE NO. DPR-65 NORTHEAST NUCLEAR ENERGY COMPANY g

THE CONNECT 8 i

THE WESTERN MASSACHUSETTS ELECTRIC COMPANY MLLSIONE NUCLEAR POWER STATION. UNIT NO. 2 DOCKET NO. 50-336

1.0 INTRODUCTION

By letter dated April 13,1998, the Northeast Nuclear Energy Company, et al. (the licensee),

submitted a request for changes to the Millstone Nuclear Power Station, Unit No. 2 Technical Specifications (TSs ). The requested changes would: (1) Increase the amount of trisodium phosphate dodecahydrate (TSP) stored in the baskets located in the containment sump and used to control the acidity /sikalinity (pH) of the sump solution after a loss-of-coolant accident (LOCA);

(2) Reduce the size of the TSP sample used for verifying its solubility and buffering capability (LOCA); (3) Add a new TS 3.5.5, " Emergency Core Cooling System - Trisodium Phosphate (TSP)," to the TS that contains a limiting condition for operation (LCO) specifying the action to be taken in restoring the TSP quantity if it becomes less than required for satisfactory pH control; (4)

Relocate surveillance requirement (SR) 4.5.2.c.3 to TS 3.5.5 as SR 4.5.5.1 and add the requirement for verification of the amount of TSP in the sump baskets; (5) Relocate SR 4.5.2.c.4 to TS 3.5.5 as SR 4.5.5.2 and specify verification frequency of the solubility and buffering capability of TSP; and (6) Relocate specific details of testing for solubility and buffering capability from SR 4.5.2.c.4 to the associated TS Bases Section 3/4.5.5.

2.0 EVALUATION While performing calculations necessary to evaluate an extended fuel c.fc!c, the licensee found that 110 cubic feet of TSP lspecified in SR 4.5.2.c.3, is not sufficient to meet the licensing basis requirement to maintain the post-LOCA sump water pH ee,ual to or higher than 7. The licensee performed a new anaiysis that included the experimental determination of pH for different concentrations of TSP and accounted for the presence of hydrochloric and nitric acids in the

post-accident environment. The analysis concluded that 282 cubic feet of TSP is required in order to maintain sump water pH at a value higher than 7. The staff verified the licensee's analysis and found it to be acceptable.

TS 4.5.2.c.4 in the current TSs requires verification solubility and buffering action of TSP by taking a 0.35

• 0.05 lbs sample from the containment baskets, immersing it for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> in m

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• 5 gallons of borated watet at 180.t 10T and measuring the resulting solution's pH. The licensee proposes to reduce the amount of TSP to 0.S662

• 0,0266 grams and dissolve it in 250

• 10 milliliters of borated water at 77

• 5V. The staff found the modification proposed by the licensee acceptable because in both cases the ratio of TSP to borate d water remains the'same and the lower solution temperature cause8 TSP to dissolve at a lower rate, wi Ah makes the test more conservative.

1 The licensee adood TS 3.5.5 to the plant's TSs to make inom more consistent with the guidance provided in NUREG - 1432,~ Rev.1, " Standard Technical Specifications for Combust;on Engineering Plants," dated April 1995 (STS-CE). This TS contains an LCD that ' specifies wnen the quantity of TSP in the sump baskets is less than required, it should be restored to its specified value in 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or the plant be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in MODE 4 within an additional 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. The staff found this proposed change acceptable because it is a new-requirement that controls the amount of TSP in the sump baskets.

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The licensee relocated SR 4.5.2.c.3, which requires verification of a minimum volume of TSP in sump baskets, to TS 3.5.5 as SR 4.5.5.1. The minimum volume of 282 cubic feet was specified and verification time of once per 18 months was added. This chang 6 makes the SR consistent with the STS-CE. The staff found this proposed change acceptable.

The licensee relocated SR 4.5.2.c.4, which requires verification of the TSP solubility and buffering capability, to TS 3.5.5 as SR 4.5.5.2 and moved the detailed description of the test to the associated TS Bases 3/4.5.5. The proposed changes are consistent with the STS-CE by adding verification time of once every 18 months to the SRs. The staff found these proposed.

changes acceptable.

3.0

SUMMARY

The stuff has evaluated the proposed TSs for post accident control of pH solution in the containment sump in Millstone Nuclear Power Station, Unit 2. These proposed changes consist of increasing the amount of TSP stored in the containment sump, reducing the size of the TSP sample used to determine solubility and bc7ering capability, and adding several editorial changes to make the plant's TSs consistent with the STS-CE. On the basis of the preceding evaluation, the staff finds that the proposed changes are acceptable because they upgrade the operability of the plant by improving the post-accident pH control of sump water and make the TSs more consistent with the STS-CE.

4.0 STATE CONSULTATION

in accordance with the Commission's regulations, the Connecticut State official was notified of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

. The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance

_ requhments. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the

amendmeriinvolves no significant hazards consideration, and there has been n., public d

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4 0 l comment on such finding ( 63 FR 25114 dated May 6,1998). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).' Pursuant to t

10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the is.uance of the amersdment.

6.0

, CONCLUSION The Commission has concluded, based on the considerations discussed above, that: (1) there is

, t' reasonable assurance that the health and saft*y of the public will not be endangered by

' operation in the proposed manner, (2) such acts: ? will be conducted in compliance with the

. Commission's regulations, and (3) the issuance of tne amendment will not be inimical to the common ce'ense and security or to the health and safety of the public.

. Principal Contributor: K. Parczewsid Date:

June 22, 1998 i

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