ML031120695

E-mail from W. Cullen to G. Demoss, Regarding Davis Besse

ML031120695
Person / Time
Site:	Davis Besse
Issue date:	10/08/2002
From:	Demoss G Office of Nuclear Regulatory Research
To:	Matthew Kirk Office of Nuclear Regulatory Research
References
FOIA/PA-2003-0018
Download: ML031120695 (14)

Text

v-Gary Demoss - Re: Davis-Be sse Paqe IN3I r:ruVr,: 1 From: Gary Demoss To: Mark Kirk Date: 10/8/02 10:38AM

Subject:

Re: Davis-Besse Mark, I'm not sure what your boss wants - but it would help me if I knew about what your comments will be on the current NRR package are. (i.e., no comment?, major comments? , can't do comment until November?, etc.)

Gary I

DAVIS-BESSE ASP ANALYSIS Ih "' RH@,>1 P"4 Manual reactor trip due to CCW 346/98-011 10/14/98 1.40e-5 Trip leak and de-energizing Buses 346/98-006 06/24/98 Tornado cause reactor trip and 5.6e-4 LOOP LOOP 346/88-007 03/04/88 CCW valves drift closed 1.6e-6 Trip 346/87-015 12/07/87 Trip due to loss of instrument air w/ 7.6e-7 Trp TBS valves open 1.0e-4* Ti 346/87-011 09/06/87 Trip with 13.8 kV bus unavailable 5.8e-6 Trip 6.1 e,4*

346/85-013 06/09/85 LOFW and AFW fails 1.1e-2 Trip 3.1 e-2* Ti 346/85-002 01/15/85 LOFW and AFW train 3.0e-4 _

8.3e-4* Ti 346/84-013 09/11/84 Trip and AVV fails 74 e-5 Trip 346/84-003 03/28/84 SFRCS transient 1.5e-4 Trip 4.1 e-4* Ti 346/83-038 07/25/83 Trip with AFW pump inoperable and 8.2e-5 Trip 346/83-040 failure of two SFRCS channels 158860 04/19/80 Loss of two essential buses 1.4e-3 UNIQ 171667 02/26/80 Loss of vital bus 1.7e-3 LOOP 146744 01/12/79 Loss of vital bus while at power <2.2e-4** LOFW 133706 12/11/77 AFW pumps inoperable during a 2.5e-2 LOFW 130121/7test <2.7e..4** LF 132927 11/29/77 LOOP 1.3e-3 LOOP 132278 LkoOnP <3.9e-4** LOO 1378 09/24/77 130788 Stuck open PORV ~<11.3e-3

.0e-2** LC LC

• Sum Probability (Includes Core Vulnerability Sequences)

• • ORNL Revised Value Slide 14 Based on Predecisic