ML20138D010
| ML20138D010 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 10/16/1985 |
| From: | Fiedler P GENERAL PUBLIC UTILITIES CORP. |
| To: | Zwolinski J Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8510230136 | |
| Download: ML20138D010 (2) | |
Text
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GPU Nuclear NggIg[
100 Interpace Parkway Parsippany. New Jersey 07054 201 263-6500 TELEX 136-482 Wnter's Direct Dial Number October 16, 1985 John A. Zwolinski, Chief Operating Reactors Branch No. 5 Division of Licensing U.S. Nuclear Regulatory Comission Washington, D.C. 20555
Dear Mr. Zwolinski:
Subject:
Oyster Creek Nuclear Generating Station (OCNGS)
Docket No. 50-219 Hydrogen Water Chemistry Test GPUN met with members of your staff on May 14, 1985 to discuss our intentions of conducting a Hydrogen Water Chemistry Test. The purpose of the test is to evaluate the feasibility of utilizing hydrogen water chemistry as a mitigator of intergranular stress corrosion cracking of stainless steel piping at the OCNGS. As discussed, GPUN intends to perform the test under 10 CFR 50.59 because, unlike other BWR's, the test can be performed without requesting a Technical Specification Change Request. Tha test is currently scheduled to be performed in December, 1985 on three consecutive back shifts. The attached is provided for your information. Should you have any questions, please contact Mr. M. Laggart at (201) 299-2341.
Very truly yours, 8510230136 851016 PDR ADOCK 05000219 P
pyg PF:gpa ler 2257f/001 Vice President and Attachment Director Oyster Creek cc: Administrator Region I U.S. Nuclear Regulatory Comission 631 Park Avenue King of Prussia, PA 19406 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, NJ 08731 J. Donohew U.S. Nuclear Regulatory Comission
(
7920 Norfolk Avenue g
Bethesda, Maryland 20014 (F
GPU Nuclear is a part of the General Pubrc Unities System I
Q 1
i ATTACHMENT Oyster Creek Nuclear Generating Station i
Hydrogen Water Chemistry Test Intergranular Stress Corrosion Cracking (IGSCC) has been identified as a i
failure mechanism of stainless steel components in domestic'and foreign Boiling Water Reactor (BWR). Laboratory and field tests have shown that
. Hydrogen Water Chemistry (HWC) can mitigate the initiation and propagation of IGSCC.
In order to determine the feasibility of utilizing a HWC program at the Oyster Creek Nuclear Generating Station (0GNGS), a HWC test will be conducted. The purpose of the test is to; 1) establish the optimum hydrogen j
feedrate to achieve maximum IGSCC mitigation and 2) perform dose rate
}
measurements both on and off site to assess the radiological impact of a HWC program.
In order to facilitate the performance of the test a HWC Test System will be installed. Upon completion of the test all installed items will be 1
removed and the system returned to its original configuration. Hydrogen will be supplied by a tube trailer located outside the turbine building. A flexible high pressure hose suitable for hydrogen service will carry hydrogen from a valve station located near the truck to the feedpump room in the turbine building basement.
Inside the feedpump room the hose will be connected to a flow control and distribution valve manifold where the hydrogen flow will be manually controlled into the suction of each of the reactor feedwater pumps. The sampling systems consist of measuring electrochemical potential (ECP) and hydrogen / oxygen concentrations in the reactor coolant as 1
j w' ell as hydrogen / oxygen concentrations in the final feedwater. A connection will be made to the existing recirculation loop sample line to facilitate the 1
reactor coolant ECP and hydrogen / oxygen analysis while an existing sample location in the feedpump room will be utilized for the final feedwater j
Hydrogen feed will be increased in small incremental steps with equal l
i hydrogen flow to all three feedwater pumps. After each incremental change plant ~ data will be taken and evaluated prior to increasing hydrogen feed.
Normal radiation protection /ALARA practices and procedures for the OCNGS will be continued through the test.
In addition, complete radiation surveys will
.be taken at hydrogen feedwater concentrations of 0.5, 1.0, 1.5 and 2.0 PPM or i
as determined necessary by our radiological controls group. Based on these surveys, protective actions will be taken, as appropriate, to control all onsite personnel exposure. A final survey will be taken at the hydrogen l
feedwater concentration necessary for IGSCC mitigation.
As a result of hydrogen being injected into the feedwater, nitrogen (N-16) i carry-over into mainsteam increases with the resultant increase in radiation levels in areas where mainsteam is routed. At i.he maximum planned hydrogen injection rate, initially to be approximately 28 SCFM, we expect to experience
,I an increase of approximately 5 times the normal mainsteam line background i
radiation levels. Currently, Table 3.1.1 of the OGNGS Technical
-Specifications establishes a trip setting of less than or equal to 10 times normal background for'the high radiation in the mainsteam line tunnel trip.
Because the test objectives should be satisfied without exceeding the current setpoint limit a Technical Specification Change is not necessary to support the test.-
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