ML20150A955

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Safety Evaluation Supporting Amend 105 to License DPR-61
ML20150A955
Person / Time
Site: Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date: 07/01/1988
From:
Office of Nuclear Reactor Regulation
To:
Shared Package
ML20150A949 List:
References
NUDOCS 8807110179
Download: ML20150A955 (5)


Text

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! o NUCLEAR REGULATORY COMMISSION

$ . ,E WASMGTON, D. C. 20665

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION E

R_ ELATED TO AMENDMENT NO.105 TO FACILITY OPERATING L,I_C_EN_SE_N0. DPR _61 CONNECTICUT YANKEE ATOMIC POWER COMPANY HADDAM NE_C_K_ _P,LANT DOCKET NO. 50-213 l

INTRODUCTION Pursuant to 10 CFR 50.90, Connecticut Yankee Atomic Power Company (CYAPC0/ licensee) proposes to amend the Operating License No. DPR-61 for the Haddam Neck Plant.

By letter dated February 19, 1988, CYAPC0 proposed to revise Technical Specification Table 3.11-1, "Containment Isolation Valves" and change the page number for Table 3.11-2.

During the 1987 refueling outage, plant modifications were implemented to containment penetrations P-7, P-10, P-23B, P-23C, P-23D, P-30, P-31, P-35, P-26, P-37, P-38, P-41, P-59, P-60, P-70, and P-728. As a result of these modifications, l

Table 3.11-1, "Containment Isolation Valves," was revised by the addition of j five containment isolation valves (CIVs) and the deletion of two CIVs.

DISCUSSION Haddam Neck Technical Specification Table 3.11-1, "Containment Isolation Valves " list CIVs that are designed to automatically close upon a high containment pressure or safety injection signal. During the 1987 refueling outage, plant modifications were implemented to various penetrations. Table 3.11-1 was revised to reflect these modifications.

EVALUATION CYAPCO will delete CIVs LM-TV-1812 and CH-MOV-331 from Table 3.11-1 and add CIVs LD-TV-230 HS-TV-380, HS-TV-381 CC-TV-917 and CC-TV-920 to Table 3.11-1.

These changes reflect plant modifications during the 1987 refueling outage.

CIV CH-MOV-331 was deleted because two new CIVs (CH-TV-240 and CH-TV-241) were installed in the Reactor Coolant Pump (RCP) seal water return line header outside of containment. Although these valves are not automatic, leakage through this line is monitored as this penetration (seal water return) is a system included in the 3 liters per hour maximur combined leakage outside i

l 8807110179 880701 PDR ADOCK 05000213 PDC f_ .__._ _ _ _

containnent allowed by Technical Specifications. In an accident mode these valves are not automatically closed because the preferred rethod for RCP cooling is maintained by keeping these valves open. These valves will be closed in accordance with plant procedures when conditions warrant their closure f.e., when seal water return is not needed and containment pressure is greater than five (5) psig. In addition, CH-MOV-331 could not isolate seal water return flow in the previous configuration.

Penetration No. P-23B was pemanently capped and seal welded. Therefore, CIV LM-TV-1812 can be eliminated from Table 3.11-1., as it no longer serves as a CIV.

Five automatic CIVs were installed during the 1987 refueling outage. These valves are incorporated into the Technical Specifications to ensure that operability requirements are applied to the valves and that the valves will be tested in accordance with 10 CFR 50, Appendix J requirements. The five valves to be added to Table 3.11-1 are:

LD-TV-230 Letdown Isolation HS-TV-380 House Heating Steam to Containnent Humidifier HS-TV-381 House Feating Steam to Cor.tainn.ent Humidifier CC TV-917 Closed Cooling Water to Neutron Shield Tank Cooler CC-TV-920 Closed Coolir,9 Water to Neutron Shield Tank Cooler LO-TV-230 is a newly installed air operated CIV which is located inside contafament in the letdown system. The letdown systen; has three CIVs (LD-A0V-202,203,?04) in parallel outside contaircent which close upcn receiving a containment isolation signal (CIS). The new valve has the sare response to a CIS as the existing three CIVs - auterratic closure. The control logic and cperator resper.ses with respect to reactor coolant systerr. (FCS) l 1etdcwn have not beer. altert;d.

This valve was added to Table 3.11-1 to ensure that Penetratfor. Ec. P-10 confoms with 10 CFR Part 50, Appendix A and that Appendix J 1 eat tests can be performed. The addition of this new A0V substantially reduces the probahility of a LOCA outside containment via a letdown line rupture that cannot be isolated.

! Overall, plant safety is enhanced by this modification.

l Penetration No. P-30 is the containment house heating steam supply header.

Modifications during the 1987 refueling outage resulted in installation of a removable spool piece in the heating main supply to containment heaters. Two CIVs (HS-TV-380 and HS-TV-381) are installed outside containment in a 1-1/2 inch bypass line around the blank flange / spool piece and serve as CIVs. During normal operation, the spool piece is removed and the blank flange is installed.

The blank flange nearest containment is also leak tested.

This house heating steam supply system does not serve any safety-related function. The system changes are not detrinental to plant safety from a systems perspective. From a containment integrity perspective, this modification enhances containment isolation capabilities by conforming to i

10 CFR Part 50, Appendix A. GDC No. 56 as compared to reliance en the original I

check valves. Both HS-TV-380 and HS-TV-381 will close on a CIS or fail closed upon a loss of power or loss of control air to the CIVs.

Penetration No. P-60 is the Component Cooling Water (CCW) supply to the neutron shield tank cooler. The CCV header to the neutron shield tank cooler previously relied on a single check valve for an isolation boundary. With the 1 modifications installed during the 1987 refueling outage, two new CIVs (CC-TV-917 l and CC-TV-920) were added outside containment.

These new CIVs close automatically upon a CIS. This is consistent with the original design in which CCW from the neutron shield tank cooler was isolated

upon a CIS by closing CC-TV-1831.

i Figures 1 and 2 provide schematics of the penetrations where modifications were made. In addition, the penetration modifications are being reviewed for compliance with the GDCs and Appendix J as part of the integrated safety assessmentprogram(ISAP). 1he NRC staff concludes that this Technical Specifi-l cation change should improve plant safety as it provides additional l containment isolation capability that can be tested to current Appendix J l

requirements.

ENVIRONMENTAL CONSIDERATION l

This anendment chinges a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The 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 radiaticn exposure. The Comission has previously published a proposed finding that the amendment involves no significant hazards consideration and there has been no public comment on such finding. Accordingly, the amendment meets j

the 10 CFRelioibility) 651.22(c criteria for categorical (9). Pursuant to 10 CFRexclusion 951.22(b), set forth in no environmental impact l

statement or environmental assessment need be prepared in connection with

! the issuance of the amendment, j CONCLUSION We have concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Comission's regulations, and the issuance of the amendment will not be inimical to the comon defense and security or to the health and safety o' the public.

Dated: July 1. 1988 Principal Contributor: Alan Wang

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FIGURE 1 p-7

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SEAL WATER QUTSIDE , ^ ,INSIDE RETURN CTMT CTMT g CH-RV-408 (

j i o o .  : :CH-V-238

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'l DG" CH-TV-241 D0 CH- TV-240 '??

X <

CH-V-237 l 7 l 'CH-V-239 l u l

' EAST PIPE TRENCH

  • CONTAINMENT ISOLATION VALVE P-10 a LETDOWN
  • LD-FCV-204

^

O OL'TSIDE * ' INSIDE CTMT CTMT

  • LD-FCV-203

)(

LD-V-217 O O )

  • LD-V-221 *

.n ,

  • 3 N

37 N """*0 LD-FCV-202 b

37 '!?'

- D LD-TV-230 A W LD-V-229 d

' L D-V-219 LD-V-384Ad '  %

D D l

EAST PIPE TRENCH P-30 OUTSIDE _ ^

~

_ INSIDE l SPACE HEATING CTMT ~ CTMT l STEAM SUPPLY

! g- h,

', ll ll  !>' > ,

'?? HS-CV-295A II  %

o .

n 4 ' ,> ^ >^  %-

HS-TV-380 ][

HS-TV-301 g WEST PIPE TRENCH

. FIGLTE 2 P-38 CCW TO RCP OUTSIDE _ ^ INSIDE

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THERMAL BARRIER CTMT CTMT I I n l

I l

l l

O

  • 3-O c.

] [ CC-V-915 i Xi l )( )( X M i

CC-V-728 lI CC-y-719] [l l l l I LJ l BL OWDOWN BL WDOWN N ROOM ' '

ROOM

  • CDNTAINMENT ISOLATION VALVE P-80 CCW TO NEUTRON

^ _ INSIDE

, OUTSIDE ~

I SHIELD COOLER CTMT ' CTMT n i n I

CC-V-882A v l g g 3 rCC-V-919 i . L i

I hh CC-TV- 917

)( li" C CC-TV-920

% ) 1)" XM CC-V-882  ; CC- V- 918 y

l CC-V-921 BL WN I WEST PIPE TRENCH N P- 41 OUTSIDE_^ INSIDE P-31 -35,-36,-37,- 59,-728 MT LOOP DRAIN HEADER OUTSIDE / INSIDE SEAL CTMT WELD

' ( CTMT

, . D h k

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THREADED n j PLUG TO CTMT a o  ;[

P-23B,C,D P-70 NN( s l" TUBIN RELIEF VALVE ' ' '

W41 REMOVED AND  % WELDED WELDED REINSTALLED INSIDE CONTAINMENT. CAP CAP