IR 05000344/1998202

Insp Rept 50-344/98-202 on 980831-0903.No Violations Noted. Major Areas Inspected:Safety Review Program Re Modular Sf Cooling Sys & Maint Program

ML20155G750
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	10/30/1998
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20155G741	List: IR 05000344/1998202 ML20155G737
References
50-344-98-202, NUDOCS 9811090176
Download: ML20155G750 (6)

Text

. _ . . _ _ . _ - . _ _ _ _ . _ . _ . . . _. . _ . . _ _ . . _.

l_-.*.'

, ...

L

,

.

U. S. NUCLEAR REGULATORY COMMISSION

,

OFFICE OF NUCLEAR REACTOR REGULATION Docket No: 50-344 License No: NPF-1

. Report No: 50-344/1998-202-L.

l Licensee: Portland General Electric Company l Facility: . Trojan Nuclear Plant Loct. tion: 121 S. W. Salmon Street, TB-17 Portland, Oregon

! ' Dates: August 31 - Sep'tember 3,1998 i-Inspectors: Lee H. Thonus, Project Manager

Approved by

Seymour H. Weiss, Director i

Non-Power Reactors and Decommissioning l Project Directorate i-

.

!

t i

.

!

9911090176 981030 PDR ce

"

ADOCK 05000344 G pm . . . . - . . ... - . . . .- ....- - - -...~ _~ ..-.- - . . . _ - _ _ - -

-

N

. .

i

.

EXECUTIVE SUMMARY This routine, announced inspection consisted of evaluation of the licensee's safety review program related to the modular spent fuel cooling system and review of the licensee's maintenance program and related discussions with licensee personnel. The inspection was conducted following the guidance of NRC Inspection Manua .

The licensee's maintenance program was well designed and implemented, including

procedural controls, work item prioritization, work backlog, and the resultant rnaterial condition during decommissioning of the plan .

The licensee's modular spent fuel cooling system design and safety evaluation were i acceptable. Some of the documentation was not clear as % the basis and intent, but the engineering staff was able to provide supplemental thformation which clarified the safety basis and limiting design parameter * The inspector closed two inspector follow-up items related to the modular spent fuel cooling system as additional information on temperature distribution and licensee evaluations of prior NRC correspondence had become available for review. The items closed are 50-344/9803-01 and 50-344/9803-0 ,

t

. . ,

-

'

,

i

. l

.

Report Details Summary of Plant Status

/

Decontamination and dismantlement of the facility with removal of components and debris I continued. The licensee completed acceptance testing of the modular spent fuel cooling system (MSFCS). During the course of the inspection the licensee began cutting and ,

capping piping from the spent fuel pool to the former spent fuel cooling syste . Safety Review Program (37801) and Inspection Follow-up (92701)

a. Inspection Scope The inspector reviewed Portland General Electric's (PGE) safety evaluation and supporting analyses and documentation related to the modular spent fuel cooling syste b. Observations and Findings PGE's safety review, performed to meet the requirements of 10 CFR 50.59, concluded that the replacement of the spent fuel cooling system with a new l modular spent fuel cooling system would not create new types of accidents, increase the probability of an accident, nor increase the severity of an acciden PGE's analysis and evaluation appeared soun The MSFCS provides redundancy for all active components, there is no reduction in safety from the original system in this regard. PGE had performed an additional, ,

more extensive, heat up test since the previous NRC inspection (50-344/98-03), i The results of this test indicated a heat up rate of 0.33 F/hr. PGE would have several days to restore power or system components prior to exceeding the plant technical specification linn of 140 F if the system were totally unavailable. Both PGE engineers and the inspector observed that the data demonstrated that as the pool temperature increased the heat up rate decreased due to the increased temperature differential between the pool and the ambient air. It appeared that the temperature would asymptotically approach a value near 140 F with time. One could easily conclude that the spent fuel pool would not reach boiling without a cooling system; it was probable but not conclusive that it would not exceed 140* A backup power system is described and available for use by towing a portable diesel generator to a pre-installed power connection point on the east side of the Fuel Building. Although it was not clear in PGE's safety evaluation, no credit was taken for this potential backup power source in the analysis. The original system had no backup power source. The inspector also found that the description of actions to be taken during cold weather with no liquid flow through the cooling coils lacked specificity. The assumed starting conditions and controls to keep within those conditions for the evaluation of a hypothetical cooling coil failure were not clear in the evaluation. ,PGE's technical staff was able to locate and provide additional clarifying information regarding the diesel, cold weather actions and

- m .m . .__._._ _. -._ _ _ . _ - -- _ _ ___ _

,

,

.

e i .  ;

.

starting conditions assumptions. They agreed that the information should be available in the safety evaluation and will revise the safety evaluation. This will be tracked as inspector follow item 50-344/98202-01, i The inspector reviewed the revised section of the MSFCS safety evaluation in which the licensee evaluated the system against relevant recent NRC Bulletins and Information Notices. The licensee's evaluation included Bulletin 94-01, Potential l Fuel Pool Draindown Caused by inadequate Maintenance Practices at Dresden Unit 1; Information Notice 97-14, Assessment of Spent Fuel Cooling; Information Notice l 98-03, Nuclear Power Plant Cold Weather Problems and Protective Measures; and information Notice 98-25, Loss of Inventory from Safety Related, Closed-Loop Cooling Water Systems. The licensee's evaluation did notidentify any MSFCS vulnerabilities with respect to the information contained in the bulletin and information notices. Inspector Follow-up item 59-344/9803-02 is close l The inspector reviewed the results of the licensee's test data which measured the variance in spent fuel temperatures with spent fuel poollocation. PGE tested a 21 point grid of locations, with three depths (6",18", and 36") at each location. The ( test was performed with the MSFCS operating and again with the system of.f. The l

test results indicated that the temperature variance for all of the locations was less than 0.5'f from the indication of the temperature sensor installed in the system.

'

j Inspection follow-up item 50-344/9803-01 is closed.

I Conclusions t

l The MSFCS is adequate to provide cooling of the spent fuel pool. The replacement of the spent fuel cooling system with the MSFCS does not decrease plant safet The licensee's safety evaluation regarding the MSFCS is adequate..

! Maintenance (62801) Inspection Scope The licensee's maintenance program was reviewed. This includes identification of systems included in the maintenance program, classification of those systems and periodic evaluation of the performance of those systems. The inspector reviewed i PGE's maintenance prioritization and work backlog. The inspector also toured the l facility and observed work in progress, fire safety precautions, and adequacy of l ingress and egis b, Observations and Findings l Trojan Plant Procedure TPP 14-23, Maintenance Rule implementation describes

,

PGE's maintenance program applicable to the spent feel pool related systems. TPP

! 14-23 included identification of those systems important to safe wet storage of fuel

(lWSF). Trojan is licensing a facility for dry storage of fuel separately under 10 CFR

!

I I

.- -- , _ _ _ _ _ _ . _ _ . _ _._ _ _ . . _ _ _ . . . ~ _ _ . _

~

.

.

.

l 3

, part 72. TPP 14-23 also included categorization of those systems and monthly and l annual review processes. The inspector found that TPP 14-23 and the supporting l MAXIMO database provided an acceptable framework for the conduct and l performance of IWSF maintenance and periodic review.

l Trojan Plant Procedure TPP 14-3, Work Control Process was used to identify, approve, prioritize and schedule maintenance and surveillance activities. The inspector found that the licensee's maintenance backlog was well controlled and that work activities were appropriately evaluated and prioritized. Only two items on the maintenance backlog had an effect on systems important to wet storage of fuel; ;

one was completed during the inspection and the other was scheduled to be worke '

PGE performs their maintenance program reviews annually in July for the previous 12 months. The inspector examined PGE's annual maintenance review, dated August 24,1998, for the period July 1,1997 through June 30,1998. The review i I

included maintenance experience at Trojan, industry wide experience, internal audits, and NRC correspondence. The inspector found PGE's annual maintenance review to be thorough and encompassin The inspector found hose reels and local fire extinguishers available and marked on each elevation of the auxiliary and fuel buildings. Irgress and egress on all observed corridors remained passable. One fire door on the 45 ft. elevation of the auxiliary

,

building was blocked open to improve ventilation flow; a compensatory fire watch l had been established. Maintenance in progress and surveillance activities observed were conducte'd in a controlled and orderly fashion with pre-job worker briefings on more complex tasks. The work observed followed the schedules of the plan of the day and plan of the wee Conclusions PGE had designed and implemented a program for maintenance activities associated with the spent fuel pool systems. Maintenance prioritization and control of work backlog were excellent. Maintenance and decommissioning activities were being conducted safel . Exit Meeting The inspector presented the inspection results to members of licensee management at the conclusion of the inspection on September 3,1998. The licensee acknowledged the findings presented. No material examined during the inspection ,

was identified as proprietary, i

,

i

!

h

.. _ .. _ -._ _ . . . . _ . - . _ _ __ - - ~

.--

,4

..

e PARTIAL LIST OF PERSONS CONTACTED

!

Licensee  !

J. Fischer, Engineering S. Ford, Maintenance D.- Gildow, ISFSI Project S. Hoag, Maintenance -

M. Lackey, Engineering / Decommissioning T. Meek, Radiation Protection

,

'J. - Minalich Engineering

, )

D. Nordstrom, Nuclear Oversight - i K. Oberloh, Operations R. Pate, Licensing J. Westvold, Licensing G. Zimmerman,' Licensing NRG L. Thonus, Project Manager Oreaon Office of Enerav A. Bless, Resident inspector INSPECTION PROCEDURES USED IP 37801 Safety Reviews, Design Changes, and Modifications at Permanently Defueled Reactors

- IP 62801 Maintenance and Surveillance at Permanently Shutdown Reactors IP 92701: Follow-up ITEMS OPENED, CLOSED, AND DISCUSSED Opened 50-344/98202-01 IFl revise MSFCS safety evaluation Gl91td 50-344/98003-01 IFl verification of adequacy of location of spent fuel pool temperature monitor 50-344/98003-02 IFl review of MSFCS against information notices and bulletins Discutand none LIST OF ACRONYMS CFR Code of Federal Regulations IFl Inspection follow-up item