ML18139A066
| ML18139A066 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 03/21/1980 |
| From: | Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8003260416 | |
| Download: ML18139A066 (5) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY RICBMOND,VIBGIN.J:A 23261 March 21, 1980 Mr. Harold R. Denton, Direct~r Office of Nuclear Reactor Regulation Attn: Mr. A. Schwencer, Chief Operating Reactors Branch 1 Serial No. 149/020880 PO/FHT:cv Docket Nos.
50-280 Division of Operating Reactors 50-281 - - ----- -
U.S. Nuclear Regulatory Commission Washington, D.* c.
20555 License Nos. DPR-32
Dear Mr. Denton:
Auxiliary Feedwater Systems Additional Information Request Surry Power Station Units 1 and 2 DPR-37 We have - reviewed your letter of February 8, 1980, Docket Nos. 50-280 and 50-281, requesting information on the S_urry Auxiliary Feedwatet (AFW) Systems.
=--=-c--=--~Q__J!_Jl_l)p_le~~nt our earlier* response, Serial No. 811/092579, dated November 9,
- =-.
- ~",:;_~*
- 0':-i~-=-~*~-/19cf9';':~;:~~=:1t::;~;~'-'-c_~------- ______ :*_~_c ----_ _.:_ ---- --- -: -
=-'-.~~-
Subsequent to. our November 9, 1979, letter, we received your letter of Decem-ber 12, 1979, requesting information on Surry AFW System automatic initiations and flow indications (TMI Lessons Learned Recommendations 2.1. 7. a and b).
Our letter Serial No. 1167/121279, dated February 1, 1980, provided the infor-mation requested in your December 12, 1979, letter.
Several of the items requested in your most recent letter of February 8 were addressed in our February* 1 response to your letter_ of December 12, 1979.
In light of this, the following response to your February 8 letter will reference our February 1 letter where appropriate~
NRC Request:
A.
Short Term Recommendations
- 5.
Recommendation ( GS-7)
Although you have verified that the auxiliary feedwater (AFW) system automatic initiation signals and circuitry are safety grade, we required additional information in order to perform an independent review and verification.
You should provide sufficient detailed
~t\\\\')
p 8003260 'T\\..b.
. ~
- --*~ -
~ -----..-..... --. --~.. --. '. -* -*-. *-- - --
e e
VIRGINIA ELECTRIC AND POWER COMPANY TO Mr. Harold R. Denton Page No. 2 information including electrical diagrams or provide a reference to the sections of the FSAR where the detailed information can be found that will allow an independent verification.
We need the detailed information before we can verify that the Surry AFW automatic initiation system meets safety grade requirements.
Response
Information sufficient to perform an independent review and verification of the AFW system automatic initiation signals and circuitry was provided in our February 1, 1980, letter, Serial No. 1167/121279.
NRC Request:
B.
Additional Short Term Recommendation
- 1.
In addition to the redundant level indication you have pro-posed, a redundant low level alarm should also be included in the design. We request that you commit to the following re-quirements regarding the indication and alarm.
- a.
The level indications should be redundant all the way from the detectors to the readouts and alarms inside the control room.-----,-_.-c-=c--c,=cc.---_-,-*,:_ ~==---- -- ____ ---------------.. -,----_----_:* :*:~ -- ---- ---~
- ** a
--- - -----~- - -
-~~--~--=---
Response
- b.
Power supplies for the indication and alarm should also be redundant.
Use of non-Class lE circuitry is accept-able for the short term provided one power train has a back-up battery source.
- c.
In the long term (1/1/81) the entire water level indica-tion and alarm systems should be designed to safety grade requirements including the use of Class 1E cir-cuitry and power supplies since the emergency condensate storage tank is designed to seismic Category I require-ments.
A design change is being prepared and will provide for redundant safety-grade level indication and alarm systems.
The new design will be imple-mented ny 1-1-81.
NRC Request:
B.
Additional Short Term Recommendation
- 2.
Your response to this recommendation is acceptable.
- However, the recommendation has since been revised reducing the endurance test from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
The attached revised Addition-al Short Term Recommendation No. 2 should be used instead of
- ._.J,-*
I VIRGINIA ELEcrRic AND PowER CoMPANY To Mr. Earold R. Denton Page No. 3
Response
the original. It is requested that you follow the provisions of the revised AFW pump endurance test provisions and submit the requested test information.
The* AFW pump endurance tests have been completed for Surry.1 (two motor driven pumps,_ one steam_:-turbine driven pump) and partially completed for Surry 2 (two motor driven pumps).
The Surry 2 steam-turbine driven pump will be tested when steam is available after Unit Startup.
Test reports are being prepared and will be forwarded as soon as they are available.
NRC Request:
B.
Additional Short Term Recommendation
- 3.
Your response to this recommendation is generally acceptable.
However, we need detailed information to demonstrate confor-mance with NUREG-0578 (2.1.7.b) criteria and clarifications in the October 30, 1979 NRC (H. Denton) letter to all operating plants; namely, single failure, testability, power supply and indication accuracy.
Response~ ':=-c:---""-*.
- -:._*- *_-_ --~--.:*:*_*_-:.. :*--, _--* ~--~:-~-~-----~:-~*,~.:- __ -:-:"" _________ ------.-~.-
- ---- -*--- --:- ~ --
- Detailed information demonstrating conformance with NUREG-0578 criteria was included in our February 1, 1980 letter, Serial No. 1167/121279.
NRC Request:
C.
Long Term Recommendations
- 1.
Recommendation (GL-3)
Your response to this recommendation is not clear.
From the
.response to GS-5 above it appears that operator action outside the control room is required following a loss of all AC power.
It also appears that the turbine driven pump may have to be operated in an on-off mode for AFW control.
In the long term we require* that, following a complete loss of AC power, no operator action should be necessary outside the control room for at least two hours.
You should also verify that on-off control of the turbine can be accomplished from the control room without AC power.
It is requested that you commit to meeting these requirements in addition to the instrumentation modifications discussed in your response in the long term.
I
~'
e VrnonnA ELECTRIC.\\ND PowER COMPANY To Mr. Harold R. Denton Page No. 4
Response
As stated in our November 9, 1979, response, our present design has at least one AFW system pump and flow path which is automatically initiated upon a loss of all AC power.
However, in order to control the amount of flow delivered, the pump must be manually operated in an on-off mode.
In order to provide automatic, or in this case, remote on-off operation from
____________ the control room, a design modification must be made.
Hence, an analysis is in progress to determine the best method for providing this capability.
The analysis and subsequent modifications will be completed and/or imple-mented by 1/1/81.
NRC Request:
C.
Long Term Recommendation
- 2.
Recommendation (GL-5)
See GS-7 for staff position.
Response
See our response to GS-7, Short Term Recommendation A.5.
_-:----------::--:-:::_.~--~-=-------==-=--=--~--=-------~-------
- -- =- - ~--------
C.
Long Term Recommendation
Response
- 3.
Recommendation (Plant Specific)
You have committed to performing the design re-evaluation requested in this recommendation.
Your commitment is accept-able.
We request that you submit the results of the re-evalua-tion for our review.
The results of our re-evaluation of the AFW system will be forwarded as soon as they are available.
NRC Request:
D.
Basis for AFW System Flow Requirements We request that you provide a commitment date for responding to the information requested in Enclosure 2 of the NRC letter dated Septem-ber 25, 1979.
('
~
f f"
e VrRorNIA Eu:crR1c AND PowER CoMPANY To Mr. Harold R. Denton Page No. 5
Response
We have requested our NSSS Vendor to develop the required basis for AFW system flow requirements and, due to the large number of utilities doing likewise, it appears that the requested information will not be available until June, 1980. We will make every effort to obtain and review this information in time to submit it for your review by July 15, 1980.
If you have further questions or require additional information, please contact this office.
Very truly yours, C. M. Stallings Vice President-Power Supply and Production Operations_
cc:
Mr. James P. O'Reilly