ML19253A298

Supplements 790806 Ltr Re Secction 3.3 of Draft Ser.Submits Addl Info on Fire Protection Program Re Instrument Air & Rerouting Hydrogen Piping

ML19253A298
Person / Time
Site:	Calvert Cliffs
Issue date:	08/17/1979
From:	Gore J BALTIMORE GAS & ELECTRIC CO.
To:	Reid R Office of Nuclear Reactor Regulation
References
013-216-0, 13-216, NUDOCS 7908210280
Download: ML19253A298 (3)

Text

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BALTIMORE GAS AN D ELECTRIC COMPANY GAS AND ELECTRIC BUILDING B ALTI M O R E, M A RYLA N D 212 03 AmTw u m E. LUN OVALL,dR-August 17, 1979 ViC E P.E 5i0( 8* f s -u Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Attention: Mr. Robert W. Reid, Chief Oper,'.ing Reactors Branch #4 Divi .on of Operating Reactors

Subject:

Calvert Cliffs Nuclear Power Plant Unit No. 1 & 2, Docket No. 50-317 & 50-318 Fire Protection Program, NRC Review File: 013-261-0, L-037-F

Reference:

(1) Draft Safety Evaluation Report by the Office of Nuclear Reactor Regulation (2) Staff / Licensee Discussions held July 11,

~

24 & 31, 1979 (3) BG&E letter dated August 6, 1979 from Lundvall to Reid Gentlemen:

The enclosures attached supplement information anc data previously furnished with reference (3) above. The referenced letter was in response to a request for information and data relative to staff positions identified in Section 3.3 of the Draft Safety Eval:ation Report (DSER).

Very truly yours,

~

1. Ih

(! Ml U.C/L-J

(

(J4 W. Core, Jr. for A. E. Lundvall,.!r.

cc: J. A. Biddison, Esquire G. F. Trowbridge, Esquire Messrs. E. L. Conner, Jr. - NRC J. W. Brothers, Bechtel 7 90 8210MO g 800 16$

J 3.3.34 ITISTDU'F'IT AIF (b .15 )

We vill recuire the licensee to:

(1) Provide a detailed inforration which surrorts the statement that the oneration of the charging syster valves are required only following a LOCA, and (2) Provide the results of an analysis which demonstrate that the transient caused by the loss of control air to the salt water valves vould not have a detrinental effect on the salt water nunts, or any adverse effect on the nlant safety. The analysis should take into account a possible delay in the enerator's action.

FESPO?!SE (1) The charging system loon isolation valves , CVC518 and CVC519, are normally onen. Both valves fail open uten loss of control air. Additionally, CVC519 is caralleled with a flow actuated bynass check valve sized to pass full charging flovrate, thereby assuring the availability of a charring flow nath even if CVC519 and CVC519 vere to be shut. This charging flow nath would also be available following a LOCA, although no credit is taken for this canability in the safety analysis.

(2) Loss of control air to the saltvater systen valves causes the service vater heat exchanger and connonent cooling heat exchanger inlet and o':tlet valves to fail onen, thereby insurine the continued availability of these heat exchangers. The salt vater systen is divided into two subsystems, each subsysten consistinc of one con-nonent cooling and one service water heat exchancer sunnlied by one salt water nunp. Uron loss o# control air, the throttling valves fail oren allowinc the punts to operate at full flow. This is analarous to the flow rate exnerienced durinc actuation of SIAS. A test and analysis found the maxinun salt vater flow fron one tu-n (i.e. one subsystet) to be 27,000 gon. S e tunn manufacturer's certified purn "erfor ance curre shows a axinun punp ficv of 28,000 gnn. The createst flov anticinated would be less than the ~axinun linit for the 'n: p, thus allowin- extended eneration of the pur" , the event of delay of operatien action.

In addition, a fu- ! nal test of the Encineered Safety Features Actuation Sys'-1 : 7 - iding SIAS is perforned each refleling as required by ' '

cal 7peci'ications with no detri ental e"fects on t aniw r nunrs or nlant safety.

C uB00 16()

3.3.39 REROUTING HYDR 0 GEN PIPING (5.4, 5.8, 5.9)

We will require the hydrogen piping in the referenced olant areas out of the areas and other safety-related plant areas, or provide other additional protection.

RESPONSE

It is our intent to provide additional protection to the safety-related areas in the aux. building containing hydrogen piping by installing an excess flow stop valve in line to the hydrogen supply to the aux. building. This valve would serve to automatically secure hydrogen to the building in the event of a piping system rupture. We would like to point out that the chance of a pipe rupture occurring is highly unlikely for the following reasons:

1. The system has been built to the following codes:

a. NFPA No. 50A-1969, Gaseous Hydrogen Systems at Consumer Sites,

b. NFPA No. 54-1969, National Fuel Gas Code.

2. With the exception of pipefittings associated with the volume control tank pressure regulator, all system oiping contained in the aux. building is welded.

3. Nomal system operating pressure is well below oice schedule design pressure, e.g., HB-21 pipe, 375 psig design /200 psig operating, HC-46 pipe, 175 psig design /

40 psig operatii.g.

(O 800 10