ML070380096

Notification of Intent to Remove a Containment Hydrogen Recombiner

ML070380096
Person / Time
Site:	San Onofre
Issue date:	02/05/2007
From:	Scherer A Southern California Edison Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML070380096 (2)

Text

SOUTHERN CALIFORNIA A. Edward Scherer P 1 EDlISON Manager of Nuclear Regulatory Affairs An EDISON INTERNATIONAL Company February 5, 2007 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

Subject:

San Onofre Nuclear Generating Station Units 2 and 3 Docket Nos. 50-361 and 50-362 Notification of Intent To Remove a Containment Hydrogen Recombiner

Reference:

Letter from L. Raghavan (U. S. NRC) to H. B. Ray (SCE) dated September 3, 1999,

Subject:

Issuance of Exemption from Certain Requirements of 10 CFR 50.44 - San Onofre Nuclear Generating Station (SONGS), Units 2 and 3 (TAC Nos. MA3543, MA3544, MA3545 and MA3546)

Dear Sir or Madam:

By the referenced letter, the U. S. Nuclear Regulatory Commission (NRC) exempted Units 2 and 3 of the San Onofre Nuclear Generating Station (SONGS 2 and 3) from certain requirements of the then-applicable regulation in 10 CFR 50.44. Among the exemptions granted was the elimination of containment hydrogen recombiners from the SONGS 2 and 3 design basis.

In a letter to the NRC dated July 19, 1999, Southern California Edison (SCE) clarified our intentions regarding the hydrogen recombiners and other hydrogen control systems, upon NRC approval of our exemption request, as follows: "...it is currently Southern California Edision's intention to continue to maintain these systems to the extent that it remains prudent and practical." "If at some future time equipment becomes inoperable and Southern California Edison decides to permanently cease repair efforts, Southern California Edison will then inform the NRC of that decision." NRC staff documented this commitment in the safety evaluation included in the referenced letter.

SCE is currently planning to replace the SONGS 2 and 3 steam generators during the cycle 16 refueling outages. One of the two hydrogen recombiners, identified by equipment number E146, in each containment building is an interference to the heavy rigging load path for the steam generators and will have to be removed. SCE and its contractors have determined that it would be more practical to remove E146 in advance during the cycle 15 refueling outage rather than during the cycle 16 outage. Hydrogen recombiner E146 will thus be out of service and removed from containment for the P.0, Box 128 San Clemente, CA 92672 949-368-7501 Fax 949-368-7575

Document Control Desk February 5, 2007 duration of cycle 15 operating cycle for both Unit 2 and Unit 3. We currently expect that the companion hydrogen recombiner, E145, in each Unit will remain operable.

For your information, the scheduled start dates for the affected refueling outages are listed in the following table. These dates are approximate and subject to change.

Unit 2 Unit 3 Cycle 15 11/26/07 10/16/08 Cycle 16 10/16/09 10/16/10 If the staff should have any questions or require any additional information, please contact Ms. Lynn Pressey at 949-368-6351.

Sincerely, cc: B. S. Mallett, NRC Region IV, Regional Administrator N. Kalyanam, NRC Project Manager, San Onofre Units 2 and 3 C. C. Osterholtz, NRC Senior Resident Inspector, San Onofre Units 2 and 3