ML20211B864

License Change Application 143 to License NPF-1,changing Containment Spray Sys Spray Additive Tank Flow Rate Surveillance Test Requirements in Tech Spec 4.6.2.2.d

ML20211B864
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	06/09/1986
From:	Withers B PORTLAND GENERAL ELECTRIC CO.
To:
Shared Package
ML20211B852	List: ML20211B846 ML20211B864 ML20211B870
References
TAC-61645, NUDOCS 8606120101
Download: ML20211B864 (4)

Text

. .

I l

l PORTLAND GENERAL ELECTRIC COMPANY EUGENE WATER & ELECTRIC BOARD AND PACIFIC POWER & LIGHT COMPANY Operating License NPF-1 Docket 50-344 License Change Application 143 This License Change Application requests modifications to Operating License NPF-1 for the Trojan Nuclear Plant to change the Containment Spray System spray additive tank flow rate surveillance test requirements in Technical Specification 4.6.2.2.d.

PORTLAND GENERAL ELECTRIC COMPANY By ^rM Bart D. Withers Vice President Nuclear Subscribed and sworn to before me this 9th day of June 1986.

A /

' ' Notary Public of C.'egon My Commission Expires: Dd Ib h 8606120101 860609 PDR ADOCK 05000344 P PDR m

O LCA 143 Page 1 of 3 DESCRIPTION OF CHAN E This change returns the Containment spray additive tank flow rate surveillance requirement in Technical Specification 4.6.2.2.d to its original format prior to the issuance of Amendment 87. The current Technical Specification is in the format described in Revision 4 to NUREG-0452, Standard Technical Specifications for Westinghouse Pressurized Water Reactors, to allow measurement of flow through drain valves CS-026 cod CS-027. This testing method will not work at Trojan, however, due to a system configuration limitation which was not recognized during testing done to support the Technical Specification change to the new format.

The proposed Technical Specification will require the NaOH tank to be drained and refilled with water. The flow rate of the water from the spray additive tank to the eductor will then be measured with the Con- '

tainment spray pump on recirculation to the Refueling Water Storage Tank (RWST). The proposed change is shown in Attachment 1.

REASON FOR CHANGE In 1981, the spray additive tank flow rate was measured by draining the NaOH from the tank, refilling the tank with water and then educting the water into the Containment Spray System with the pump on recirculation to the RWST. This testing verified the flow rate from the spray additive tank to be 37 3 spm. Subsequently, a data acquisition test was run to support a Technical Specification change to allow verification of spray additive flow rate by gravity drainage from system drain valves with NaOH in the tank in accordance with Revision 4 of NUREG-0452, Standard Technical Specifications for Westinghouse Pressurized Water Reactors.  !

The data acquisition test measured a flow rate of approximately 28 spm ,

of NaOH for each train of Containment spray. These values were used to i change the Technical Specifications.

This year, while performing the test for the first time under the new Technical Specification, a flow of only approximately 16 spm of NaOH was achieved through each drain valve. While performing the test by gravity drainage of water from the RWST, a flow of approximately 28 gpm was measured. After several attempts to achieve the required flow rates with NaOH, a line-loss calculation was performed to determine the expected flow rate from the drain valves. The calculation showed the flow rate should be 14.35 spm with the limiting line-loss component being the i 3/4-in. drain valves. This result corresponded well with the measured NaOH flow rate. In order to verify a flow rate of 34-40 spm from the spray additive tank, the throttle valves (CS-003 and CS-004) must be the limiting line-loss components. Therefore, it was determined this test methodology could not be utilized at Trojan as it would not demonstrate the system could achieve the design flow rate. It is suspected that a valve lineup error was made when the data acquisition test was run in 1981 and that gravity flow from the RWST was what was measured at that time.

l LCA 143 Page 2 of 3 Since the inadequacy of the test could not have been identified until the test was run, the need for the emergency Technical Specification change could not have been averted. It should be noted, however, inat the test has a 5-year periodicity and the test will not be overdue until after September 1, 1987. Therefore, the Technical Specification chenge is actually required in time to allow the test to be completed by then.

The inability to perform the test in accordance with the Technical Speci-fications does not render the system inoperable, but demonstrates the Technical Specification is not adequate for determining operability. The system is still considered to be in an operable condition since this was demonstrated in 1981 by successful performance of the surveillance test previously described in the Technical Specifications. Since the previous test was adequate for demonstrating system operability, it is proposed that the Technical Specification surveillance requirement be changed back to the original surveillance requirement. As long as this change is made in time for the test to be performed within the surveillance test inter-val, the Technical Specifications will be satisfied. In the interim, gravity flow tests have been performed to demonstrate the spray additive tank outlet line is not blocked. Two tests were performed, one with MO-2056A and both drain valves (CS-026 and CS-027) open and one with MO-2056B and both drain valvos open. Flow rates through the spray additive tank outlet line of approximately 30 gpm were achieved. Cal-culations to support this flow test predicted flow rates of approximately 26.5 spm. Therefore, it has been concluded the spray additive tank out-let line is not blocked and the system would achieve 34-40 spm of spray additive flow.

SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION This change does not involve a significant increase in the probability or consequences of an accident since this change only proposes an alternate method for verifying operability of the spray additive system. There-fore, the proposed change does not alter the likelihood of supplying NaOH to the Containment spray water nor the amount of NaOH supplied.

This change does not create the possibility of a new or different kind of accident. Neither the design of the Containment Spray System nor the manner in which it would be operated in an accident are being altered.

The design basis of 34-40 gpm of spray additive flow is not being changed, only the method for verifying that flow is being changed. The proposed change to Surveillance Requirement 4.6.2.2.d is not related to accident creation.

This change does not involve a significant reduction in a margin of safety. Since no change is proposed to the Limiting Condition for Operation, the spray additive system will continue to ensure that:

(1) the iodine removal efficiency of the spray water is meintained, and (2) corrosion effects on components within containment are minimized, to the same extent as assumed in the accident analysis.

LCA 143 Page 3 of 3 In the April 6, 1983 Federal Register, the NRC published a list of examples of amendments that are not likely to involve a Significant Hazards Consideratior.. Example No. 2 of that list applies to this change and states:

"A change that constitutes an additional limitation, restriction, or control not presently included in the Technical Specifications, eg, a more stringent surveillance requirement."

This example is judged to apply because the proposed change requires an operational test using the Containment spray pumps as opposed to the less restrictive gravity flow test through drain valves.

Based on the above evaluation, the proposed change does not pose a significant hazard.

S_AFETY/ ENVIRONMENTAL EVALUATION Safety and environmental evaluations were performed as required by 10 CFR 50 and the Technical Specifications and are summarized below.

Since the change only proposes a different method for verifying operabil-ity of the spray additive system, the probability or consequences of an accident are not increased, nor is there a possibility of creating a different kind of accident. For the same reason, the probability or consequences of a malfunction of equipment important to safety are not increased, nor is there a possibility of creating a different kind of malfunction.

This change does not affect the Bases of the Technical Specifications or any FSAR analyses because no change is proposed which affects the assumptions or results of the accident analyses.

This change does not have any environmental effect because this change does not involve an unreviewed environmental question and no affect to the public health and safety will occur.

SAB/kal 5770k.686 l

i

._ . _ .