ML20057A350
| ML20057A350 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 09/02/1993 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20057A346 | List: |
| References | |
| GL-90-06, GL-90-6, NUDOCS 9309140060 | |
| Download: ML20057A350 (7) | |
Text
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UNITED STATES E
~,t NUCLEAR REGULATORY COMMISSION 7,
E WASHINGTON. D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.164 TO FACILITY OPERATING LICENSE NO. OPR-61 1
1 CONNECTICUT YANKEE ATOMIC PCWER COMPANY j
HADDAM NECK PLANT i
DOCKET NO. 50-213
1.0 INTRODUCTION
By letter dated May 19, 1993, the Connecticut Yankee Atomic Power Company (CYAPCO, the licensee) submitted a request for changes to the Haddam Neck Plant Technical Specifications (TS). The requested changes will revise the
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Technical Specifications (TS) to reflect staff positions and improvements to i
the TS in response to Generic Letter (GL) 90-06, " Resolution of Generic Issue (GI) 70,
- Power-0perated Relief Valve and Block Valve Reliability,' and i
4 Generic Issue 94,
- Additional Low-Temperature Overpressure Protection for Light Water Reactors.'"
2.0 EVALUATION j
By letter dated June 25, 1990, the staff issued GL 90-06. The GL represented the technical resolution to GI 70 and GI 94. GI 70 involves the evaluation of the reliability of pressurizer power-operated relief valves (PORVs) and block valves and their safety significance in pressurized water _ reactor plants. The GL-discusses how PORVs are increasingly being relied on to perform safety-related functions, and the corresponding need to improve the reliability of both the PORVs and their associated block valves. The GI 94 addresses concerns with the implementation of the guidance set forth in the resolution of Unresolved Safety Issue A-26, " Reactor Vessel Transient Protection (Overpressure Protection)." The GL 90-06 discusses the continuing occurrence of overpressure events and the need to further restrict the allowed outage time for a low-temperature overpressure protection (LTOP) channel in operating Modes 4, 5, and 6.
By letters dated December 21, 1990, March 21, 1991, August 20, 1992, and October 1,1992, CYAPC0 submitted initial and revised responses to the staff.
The staff has reviewed those responses and has concluded that they are acceptable.
In these responses, the licensee stated that it would propose TS changes regarding PORY operability and LTOP reliability based on the TSs provided in the GL 90-06 attachments. By letter dated May 19, 1993, CYAPCO provided these TS changes completing their commitments for the resolution of i
In addition, the licensee noted that while the TS are based upon i
9309140060 930902 PDR ADOCK 05000213 P
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l the technical specifications provided in GL 90-06, it will have differences reflecting the plant specific design.
Generic Issue 70 The licensee currently has a TS Section 3.4.4, " Relief Valves," which addresses the PORVs.
The licensee has proposed to modify the current TS to meet the requirements proposed by the GL 90-06. The evaluation will address the differences or additions from the TSs proposed in the GL 90-06.
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l 2.1 Section 3/4.4.4. " Relief Valves" l
Limitina Condition For Operation (LCO) 7
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The proposed TS deviates from the proposed TSs in GL 90-06 because the i
licensee has included the PORV and block valves setpoints and the minimum emergency air supply pressure.
The licensee has added several conditions not required by the TSs proposed in the GL 90-06. The addition of the setpoints is of no safety significance since no safety analysis takes credit for the automatic actuation of the PORVs in Modes 1, 2, or 3 transients (applicability modes of LCO).
The addition of the emergency air supply pressure is a restriction to assure the emergency air supply system can support a minimum number of PORY operations after the normal air supply is lost. The PORVs are i
used during " feed and bleed" and this statement represents a plant specific design feature to support this operation. The staff has reviewed these changes and has concluded the proposed TS with additional restrictions comply with the TS as proposed by GL 90-06 and will provide additional assurance of PORV operability.
Based on the above the staff concludes that the proposed TS 1
amendment acceptable.
Action Statement a The licensee has replaced the phrase "because of excessive seat leakage" with "and capable of being manually cycled." PORV inoperability may be due to seat leakage, instrumentation problems, automatic control problems, or other causes that do not prevent manual use and do not create a possibility for a small break loss-of-coolant-accident (LOCA). Therefore, the PORVs may be declared inoperable and still be able to be manually opened and closed and to perform its safety function. This wording is consistent with the wording in the standardized TS (STS) relief valve and bases sections.
In addition, the Haddam Neck plant operates with the block valve normally closed. Manual 4
control is established at Haddam Neck when the PORVs or block valves are placed in the "close" position which defeats the automatic function. This is different from most plants because at Haddam Neck the block valves receive the same signal to open as the PORVs. Therefore, in most cases there would be no need to close the block valve only verify that the block valve is closed and place it in manual control.
The licensee has changed the wording to "be in i
hot shutdown within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />" from "be in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />." This is consistent with the TS as provided in GL 90-06 and is the first Mode for which the LCO does not apply. The staff has
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- l reviewed the changes from the TS as provided in GL 90-06 and has determined J
the proposed TS do not ' decrease the level of safety or change the intent of j
the GL and therefore, the staff concludes the proposed TS comply with staff positions as proposed in GL 90-06.
j Action Statements b and c The licensee has replaced the phrase "due to other causes other than excessive seat leakage" with "and not capable of being manually cycled." This wording 1
is consistent with the wording in the standardized.TS (STS) relief valve and bases sections. The licensee has changed the wording to "be in hot shutdown
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within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />" from "be in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />." This is consistent with the TS proposed in GL 90-06 and is the i
j first Mode for which the LCO does not apply. The staff has reviewed the changes from the TS proposed in GL 90-06 and has determined these changes do
- t not decrease the level of safety or change the intent of the GL and therefore, the staff concludes the proposed TS comply with the TS as proposed in GL. 90-06.
Action Statement d i
l This action statement is the associated action statement for the LC0 for the emergency control air supply system. The addition of the emergency air supply pressure is a restriction to assure the emergency air supply system can support a minimum number of PORV operations after the normal air supply is lost. The PORVs are used during " feed and bleed" and this statement represents a plant specific design feature to support this operation. This action statement provides additional assurance that systems supporting the PORVs are operable. This action statement enhances the operability and j
reliability of the PORVs and therefore, the staff concludes the proposed TS is acceptable.
Action Statement e This action statement provides the remedial actions for inoperable block i
valves and is consistent with the TS provided in GL 90-06 except for including the condition that the block valve (s) are not capable of being manually cycled. This change is acceptable because Action statement (f) addresses inoperable block valves and capable of being manually cycled.
In addition, manual control is established at Haddam Neck when the PORVs are placed in the "close" position which defeats the automatic function. As noted above Haddam Neck operates with the block valves closed and the block valves receive the same signal to open as the PORVs. The staff has concluded that the proposed TS comply with the TS provided in the GL 90-06.
Action Statement f This action statement complements Action statement (e) as it addresses inoperable block valve (s) and capable of being manually cycled. The prime importance of the block valve is the capability to close to isolate a stuck-a
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! l open PORV. Therefore, if the block valve (s) can be manually controlled, the remedial action is to place the PORY in manual control to preclude its automatic opening for an overpressure event and to avoid the potential of a i
stuck-open PORV at a time that the block valve is inoperable. The loss of automatic function is of no safety significance since no safety analysis takes credit for the automatic actuation of the PORVs in Modes 1, 2, or 3 transients (applicability modes of LCO). Therefore, the PORVs and block valves may be declared inoperable and sti;l be able to be manually opened and closed and to perform their safety function. The staff has reviewed the changes from the TS as provided in GL 90-06 and has determined these changes do not decrease the level of safety or change the intent of the GL and therefore, the staff concludes the proposed TS comply with the TS as provided in GL 90-06.
Surveillance Reauirements i
The surveillance requirements proposed are consistent with the TS as provided in GL 90-06 except the licensee has provided additional surveillances for the PORVs, block valves and the emergency control air supply. The licensee has added an 18 month analog channel operational test for the PORVs and block valves and a quarterly stroke test for the block valves. The emergency control air supply system will also have an 18 month operability test to demonstrate the integrity and operability of the system. These additional surveillance requirements enhance the operability and reliability of the PORVs j
j and therefore, the staff concludes these additional restrictions are acceptable.
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As noted earlier, the pressurizer relief valve system at the Haddam Neck Plant is different from most operating plants because it operates with both the PORV and block valves closed and manual control is established by placing the PORVs i
or block valves in the closed position. Therefore, most of the differences in the proposed TS are due to this plant specific configuration or wording-danges provided in the latest version of the STS. Based on the above the staff has concluded that the proposed TS meets the general guidance provided in GL 90-06 and will improve the reliability of both the PORVs and their associated block valves. With the issuance of this TS, we consider Generic 4
Issue 70 complete.
Generic Issue 94 4
q The licensee currently has a TS Section 3.4.9.3, " Low-Temperature Overpressure Protection Systems," which addresses those systems used in resolving Generic Issue 94. The licensee has proposed to modify this current TS to meet the requirements of the TS as provided in GL 90-06. At the Haddam Neck Plant the LTOP system consists of two relief trains, each with two motor-operated isolation valves and one spring-loaded relief valve (SRV) all in series. The LTOP system, in conjunction with a vent opening of at least 7 square inches, ensures that the RCS will be protected as required by 10 CFR Part 50, Appendix G.
As noted earlier, the licensee has stated that while the TS are based upon the technical specifications'provided in GL 90-06, it will have i
differences reflecting the plant specific design. The evaluation will address i
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. the changes made to the TS provided in GL 90-06 to reflect plant specific design.
2.3 TS Section 3.4.9.3. " Low-Temperature Overoressure Protection Systems" Limitina Condition for Operation and Aeolicability The Haddam Neck Plant uses spring-loaded relief valves rather than PORVs.
Therefore, any references to PORVs have been replaced with SRVs. The TS has two clarifying statements which are not included in the proposed TS in GL 90-
- 06. The licensee has made an exception to LTOP operation during Mode 4 for the performance of the hydrostatic or leak testing.
In addition, for Modes 5 and 6, the licensee has made a clarifying statement that the LTOP shall be placed in service prior to placing the RHR system in service.
The staff has reviewed these changes and concludes that the proposed TS follows the general guidance of the TS in GL 90-06. The changes provide exceptions or clarifications which represent plant specific design and the staff concludes that these changes are acceptable.
Action Statement a The differences in this statement from the proposed TS in GL 90-06 are clarifying statements that have been added to assist the plant operators in the actions to be taken. However, CYAPC0 has modified this Action statement to provide an additional 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to enter cold shutdown, in addition to the 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to vent and depressurize the system. CYAPC0 requested the additional 4
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hours from a personal safety standpoint. The staff has denied this 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> increase because the staff believes the 7 days provides sufficient time to restore the inoperable relief valve or determine that the plant will need to enter cold shutdown and establish a vent. The additional time margin requested for establishing the vent can be taken from the 7 day limit, and no deviations would be required from the proposed TS provided in GL 90-06. The proposed TS however does provide clarifications for the operators. The staff concludes that this Action statement with the denial of the additional 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to enter cold shutdown meets the general guidance of the TS provided in GL 90-06 and is acceptable.
Action Statement c The licensee uses slightly different wording but the intent of the TS provided in GL 90-06 is maintained. The staff concludes the wording change is of no safety consequence and the proposed TS is acceptable.
Surveillance Reouirements The licensee uses slightly different wording to represent plant specific design but the intent of the TS as provided in GL 90-06 is maintained. The staff concludes the wording changes are of no safety consequence and the proposed TS comply with staff positions in GL 90-06.
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The major difference regarding this TS from GL 90-06 TS is the use of SRVs instead of PORVs for the LTOP system. Therefore, most of the differences in the proposed TS from the GL 90-06 TS are due to this plant specific configuration or wording changes provided to assist the operators. Based on the above the staff has concluded that the proposed TS will restrict the allowed outage time for a LTOP channel in operating Modes 4, 5, and 6 as recommended in GL 90-06.
With the issuance of this TS, we consider Generic Issue 94 complete.
2.4 Ba.su a
The licensee has provided additional discussions on PORV and block valve operation. These revisions reflect changes made to the TS. The added I
discussions will provide the operators with additional information on acceptable plant configurations and actions to be taken when an inoperable PORV or block valve is discovered. The staff has reviewed the proposed changes to the Bases and we agree it will not affect the safety of the plant.
As the changes only provide clarifying information, we find these changes acceptable.
3.0 STATE CONSULTATION
i In accordance with the Commission's regulations, the Connecticut S m i
official was notified of the proposed issuance of the amendment. The State official had no comments.
4.0 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 I
Part 20 and changes surveillance requirements. 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 amendment involves no significant hazards consideration, and there has been no public comment on such finding (58 FR 32380). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
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5.0 CONCLUSION
The Commission has 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, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
A. Wang Date: September 2, 1993 1
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