ML20135D134

Annual Rept of Facility Changes for 1984

ML20135D134
Person / Time
Site:	Humboldt Bay
Issue date:	12/31/1984
From:	PACIFIC GAS & ELECTRIC CO.
To:
Shared Package
ML20135D132	List: HBL-85-041, Forwards Annual Rept of Facility Changes for 1984, Per 10CFR50.59.Complete Records for Each Mod,Including Written Safety Evaluations,Maintained at Plant ML20135D134
References
NUDOCS 8509130358
Download: ML20135D134 (3)

Text

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PGandE Letter No.: HBL-85-041 ENCLOSURE HUMBOLDT BAY POWER PLANT UNIT NO. 3 DOCKET NO. 50-133 ANNUAL REPORT OF FACILITY CHANGES FOR 1984 Pacific Gas and Electric Capany

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8509130358 850904 PDR R ADOCK 05000133 PDR 0457S/0036K~

DESCRIPTION OF FACILITY CHANGES WHICH AFFECT THE PLANT AS DESCRIBED IN THE SAFETY ANALYSIS REPORT

1. DCR HB3-0-SE-097, Circuit Breaker Control Transformer Secondary Fuse Inspections of circuit breakers at HBPP determined that approximately 95 percent of the circuit breaker control transformers had secondary side fuses that were sized too large for the transformer rating. These fuses were replaced with properly sized fuses.

Safety Evaluation Summary Reduction of the transformer secondary fuse rating will protect the transformer from overloading which could result in a fire and damage the breaker. System designs provide redundant equipment to protect against breaker failure. Reducing the size of the fuses will not result in an unreviewed safety question.

2. DCR HB3-0-SI-106, Liquid Radioactive Waste Discharge Process Ibnitor The liquid radioactive waste discharge process monitor was originally installed during plant construction in 1962. Due to its design and age, the monitor had become very difficult to calibrate and maintain. A new nonitor was installed that does not have these problems. The nei monitor has a shielded monitor cavity, which enhances the accuracy of the instrument.

Safety Evaluation Summary Since the new monitor performs the same function as the original monitor, an unreviewed safety question does not exist. Replacement of the original monitor does not increase the potential for an unintentional release of radioactive material.

, 3. DCR HB3-0-SM-lll, Resin Storage Tank Conversion To Laundry Waste Hold Tank This modification converted the resin storage tank from the condensate demineralizer system to a laundry waste hold tank and permits draining of the existing laundry waste tank into the new laundry waste hold tank. As a result, the contents of the waste hold tank can be analyzed prior to release. This allows operation of the laundry to continue while waiting for analyses results.

Safety Evaluation Summary This modification does not increase the potential for an unmonitored release of radioactive waste since the tanks and piping are all contained within plant structures and are adequately drained to the plant radioactive waste collection system.

0457S/0036K  !

1 1 4. DCP. HB3-0-SI-116, Gas Treatment System The gas treatment system sample valve was replaced with a carbon steel valve. The fonner valve i.as constructed of brass. Caking of sodium hydroxide on the valve seat had caused the valve to leak. The carbon steel valve is more resistant to corrosion from the caustic solution in the system.

Safety Evaluation Summary An unreviewed safety question does not exist since the carbon steel valve is less susceptible to corrosion from sodium hydroxide and, therefore, is an improvement over the former valve.

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