ML18064A437
| ML18064A437 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 10/27/1994 |
| From: | Haas K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9411020205 | |
| Download: ML18064A437 (5) | |
Text
consumers Power POW ERi Nii MICHlliAN"S PIUlliRESS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway, Covert, Ml 49043 October 27, 1994 Nuclear Regulatory Commission ATTN:
Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT KurtM. Haas Plant Safety and Licensing Director EMERGENCY DIESEL GENERATORS - COMPLETION OF FUEL OIL SUPPLY SYSTEM MODIFICATIONS-SUPPLEMENTARY INFORMATION On June 6, 1994, Consumers Power Company provided a submittal to the NRC which included our plans to upgrade the fuel oil supply system for the Emergency Diesel Generators {EDG).
In the submittal we committed to permanently install a seven day fuel supply that complies with GDC-2, and to inform the NRC when the modifications will be completed.
On June 7, 1994, the NRC approved continued operation of Palisades, with interim compensatory measures and commitments, until the permanent modifications are implemented.
This letter provides the results of preliminary engineering for the planned upgrade.
The intent is still to complete the actions as soon as possible, but no later than the end of the refueling outage following the 1995 Refueling Outage.
Presently, the on-site EDG fuel oil supply system has the design deficiencies identified in the following paragraphs.
These deficiencies were also identified in a May 23, 1994, submittal that provided a Justification For Continued Operation. These deficiencies prevent the system, and associated components, from meeting the full qualification requirements regarding the
- ability to withstand the effects of postulated natural phenomena.
The planned actions to eliminate the deficiencies are also identified.
As stated in the June 6th submittal, the design of the electrical power and control circuits for the fuel oil transfer pumps will not be upgraded.
The presently approved electrical design will be maintained to provide reliable power and control functions.
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9411020205 941027
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I P.DR ADOCK 05000255 p
o' DEFICIENCY 1 - TANK T-10 The design of fuel oil supply tank T-10 does not ensure that the tank can withstand the effects of a tornado missile. Also, analysis can not be found that determines that the tank T-10 design can with~tand the effects of design basis flooding.
CORRECTIVE ACTION 2
The planned action is to replace tank T-10 with a new tank design that includes tornado missile protection and flooding qualification. The proposed change is shown on Figure 1.
The new tank is targeted for installation during the refueling outage following the 1995 refueling outage.
DEFICIENCY 2 - PIPING QUALIFICATION There are portions of the fuel oil piping from tank T-10 to the EOG day tanks that have not been verified to be capable of withstanding the effects of a tornado missile or a seismic-event.
The following piping design deficiencies exist:
2.1 The design of tank T-10 outlet piping, located outside and prior to entry into the intake structure, has not been verified to be capable of withstanding the effects of tornado missiles.
2.2 The design of the fuel oil piping within the intake structure has not been verified to be capable of withstanding the effects of a seismic event.
2.3 The design of the underground piping that runs from the intake structure to the EOG 1-2 room has not been verified to be capable of withstanding the effects of tornado missiles.
2.4 The design of the fuel oil piping in the EOG rooms that supplies the EOG day tanks has not been verified to be capable of withstanding the effects of a seismic event using detailed analytical techniques.
CORRECTIVE ACTIONS For deficiency 2.1, the outside p1p1ng from tank T-10 to the intake structure is presently being evaluated and the underground portions appear to have sufficient depth to not be vulnerable to tornado missile effects.
The analysis will be completed during conceptual engineering for the tank T-10 modification.
The above ground portions of the outside piping will be protected from tornado missiles, or modified to run totally underground into the qualified intake structure. This piping modification is also part of the facility change for the tank replacement and will be compl-eted by the end of the refueling outage after the 1995 Refueling Outage.
3 For deficiency 2.2, the design of the above ground fuel oil p1p1ng in the intake structure is presently being evaluated for seismic adequacy.
Several minor piping support upgrades appear to be required to meet Palisades FSAR seismic requirements.
The piping analysis will be completed by 12/15/95. The associated modifications will be completed by the end of the refueling outage following the 1995 refueling outage.
For deficiency 2.3, the underground piping that runs from the intake structure to EOG 1-2 room appears to have sufficient depth to not be vulnerable to a tornado missile.
The analysis will be completed by 12/15/95.
For deficiency 2.4, the as-built configuration of the piping was previously verified to meet the criteria of a support span chart methodology.
The method was developed for small bore piping as a follow-up to IEB 79-14.
A review of this piping system will be conducted to ensure applicability of the support span chart methodology, and if needed a more detailed analysis will be performed.
If required, the detailed analysis will be completed by 12/15/95.
DEFICIENCY 3 - ISOLATION OF NON-ESSENTIAL LOADS The design of the fuel oil supply system ~oes not provide automatic isolatibn of non-essential fuel oil loads upon the initiation of a design basis event.
CORRECTIVE ACTION The present design appears to maintain the proper-balance between two competing design alternatives: 1. A fuel oil supply system solely dedicated to the EDGs, that is vulnerable to fuel oil degradation due to ~low turnover of the fuel oil, and
- 2.
An EOG fuel oil supply system also connected to non-essential and non-qualified fuel oil loads, that is vulnerable to fuel oil flow diversion to the non-essential loads or piping failures.
The proposed new system will maximize the benefits of both alternatives as described below.
The identified actions will be completed by the end of the refueling outage following the 1995 refueling outage.
The actions are:
A.) Maintain the present fuel oil pump electrical design that ensures that manual operator action is required to start fuel oil pumps after the completion of electrical load shed.
As discussed in the Justification for Continued Operation, May 23,1994, this present design significantly reduces the chance of pumping oil to potentially failed piping in the non-essential header; B.) Revise operating procedures to provide actions to conserve fuel oil inventory and eliminate diversion of fuel oil to non-essential fuel oil loads during a design basis event;
i*
C.) Replace the present 30,000 gallon tank T-10 with an approximate 45,000 gallon tank to provide fuel oil inventory margin. The margin will ensure any flow diversion to non-essential loads will not impact the minimum inventory required for the EDGs.
SUMMARY
OF COMMITMENTS 4
This letter contains no new commitments.
The original commitment to provide a qualified 7-day diesel fuel oil supply by the end of the refueling outage following the 1995 Refueling Outage remains unchanged.
I Kurt M Haas Plant Safety and Licensing Director CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades*
Attachment
CONCRETE ENCASEMENT FILL T-q2s FUEL OIL STORAGE TANI<
.'-~~~~~.~
ournqoRs INTAKE
, STRUCTURE P-IBA/B FUEL OIL TRANSFER*
PUMPS TO FIRE PUMP DAY TANl<S BURIED AUXILIARY BUILDING 2' /3 ODO D 0 2500 KW DIESEL SET K-6A 1-1 0 0 0 0 0 2500 KW OIESEL SET K-66 1-2 Tl 1---t C1 c
- 0 nl