ML20236S254

Special Rept 98-01:on 980629,diesel-driven Fire Pump Was Inoperable for Greater than Seven Days.Caused by Sheared Off Tie Rods on Accessory Drive End of Engine.Evaluated Condition,Procured Parts & Replaced Tie Rods

ML20236S254
Person / Time
Site:	Duane Arnold
Issue date:	07/14/1998
From:	Van Middleswort IES UTILITIES INC., (FORMERLY IOWA ELECTRIC LIGHT
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NG-98-208, NUDOCS 9807240225
Download: ML20236S254 (2)

Text

--

3 +."

ALLI ANT g UTILlTIES as usine Inc.

IES Utilities [2Elu^I8O""'""'"

Palo, IA $2324-9785 OfGce: 319.85L7611 Fax: 319.851.7986 www.alliant energy.com NG-98-1208

'l' U. S. Nuclear Regulatory Commission

. Attn: Document Control Desk .

Mail Station 0-PI-17 Washington, D.C. 20555-0001

Subject:

Duane Arnold Energy Center DocketNo: 50-331 Op. License No: DPR-49 Special Report #98-01 For inoperable Diesel-Driven Fire Pump File: A-105, A-Il8

Dear Sir:

The Duane Arnold Energy Center Fire Plan section 12.1.B.2 (referenced in UFSAR section 13.7.1), states that, "When only one pump is OPERABLE restore the second fire pump to OPERABLE status within seven' days or prepare and submit a Special Report to the NRC within the next 30 days outlining the plans and procedures to be used to provide for the loss of redundancy in this system". This Special Report is being submitted regarding the diesel-driven fire pump being out of service for greater than seven days.

^

During the out of service period for the diesel-driven fire pump, the electric fire pump was operable, and backup water sources were available from General Service Water and the Well Water system. 7 On June 29,1998, planned maintenance on the diesel-driven lire pump,1P049, was commenced Avi- ]

under a seven day LCO to replace the head shaft sleeve, install new pump packing, and perform

. scheduled preventive maintenance. Due to an emergent equipment issue described below, the l' l work effort expanded.

During post-maintenance inspection and conduct of overspeed testing (Surveillar.ce Test i

Procedure NS13B001) on July 2,1996, a mechanic noticed that the tie rods between the engine L mounting castings were vibrating excessively. Further examination revealed that both tie rods I- had sheared off en the accessory drive end of the engine. The point of shear, at the nut, was hard to see without taking special effon. Evaluation of the condition, pans procurement, and installation ~of the replacement tie rods was not completed before the seventh out of service day, f g

-[Y EEo ,

w,2 July 14,1998 NG-98-1208 i

. Page 2 of 2 I

Work was completed on July 6,1998, and the fire pump declared operable. During the period {

between the discovery of the degraded tie rods and their subsequent replacement (July 2 to July 6), the diesel-driven fire pump was available for emergency use, but not declared operable.

A review of maintenance history found that Special Report #93-01 was written on 3/26/93 due to a failure of the diesel fire pump right angle drive studs during pump testing. This is not a repeat faihire, but similar in requiring more than seven days for resolution and thus exceeding seven .

days in inoperable status.-

If you liave any questions regarding this matter, please contact my office.

Sincerely,- i f

m G Van Middlesworth Plant Manager- Nuclear i

cc: C. Paperiello (Region III) .

l NRC Resident Inspector-DAEC 1 R. Laufer (NRC-NRR)

DOCU l

i 1

f i

l l

l t___ _ _ . _ _ . . _ _ _ _ _ . _ _ . _

j