ML19338C578
| ML19338C578 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 08/07/1980 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-80-17, NUDOCS 8008180169 | |
| Download: ML19338C578 (4) | |
Text
'e TENNESSEE VALLEY AUTHORITY CH ATTANOOG A. T&$NNSE 37401
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Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Region II - Suite 3100 101 Marietta Street Atlanta, Georgia 30303
Dear Mr. O'Reilly:
OFFICE OF INSPECTION AND ENFORCEMENT BULLETIN, SUPPLEMENT 1 - RII:JPO 50-259, -260, -296 - BROWNS FERRY NUCLEAR PLANT IE Bulletin 80-17 Suplement No.1, dated July 18, 1980, was transmitted to us by your letter to H. G. Parris dated July 18, 1980. Enclosed is our response to Action Item A of the bulletin supplement.
If you have any questions, please call Jim Domer at FTS 857-2014.
Very truly yours, TENNESSEE VALLEY AUTHORITY a
. M. Mills, Kanager Nuclear Regulation and Safety Subscribed p'nd sworn to before me this 9 ' day of //h/;/6b 1980.
- Wn,.$k. hMLW Notar Public
() My Commission Expires /k4JfM $ /[IL / Enclosure ec: Office of Inspection and Enforcement (Enclosure) U.S. Nuclear Regulatory Commission Division of Reactor Operations Inspection Washington, DC 20555 An Equal Opportunity Employer $%ICI
1 ENCLOSURE IE BULLETIN 80-17, SUPPLEMENT NO. 1 BROWNS FERRY NUCLEAR PLANT (DOCKET NOS. 50-259, -260, -296) ITEM A.1 Provide to the NRC regional office an analysis of the adequacy of the "as built" SDV system and associated vent and drain systems,' including any identified design deficiencies. Include copies of verified "as built" isometric drawings of the SDV and detailed descriptions of the remainder of the systems, verified to be correct, as part of this analysis. i
RESPONSE
Attached are "as built" isometric drawings of the SDV system and associated drainage systems (clean radwaste). These drawings have been recently generated by field personnel at the site using actual measurements. TVA has reviewed the present eystem and ussociated vent and SDV d-ain system. We fl.nd that, in principle, the design is adequate, particularly considering the additional ultrasonic moni.oring being currently performed. Details of the system design and operating bases were presented to the NRC Staff on July 29, 1980, in the IE Region II offices. Also, system performance data collected during the IE Bulletin 80-17 tests have been submitted to your office. We have identified areas which warrant improvement to increase the overall reliability of the system and to eliminate the possibility of undetected failures. TVA is evaluating a number of internally proposed design changes, as well as General Electric Company proposals. The current effort is appropriately directed toward an integrated system evaluation and modification with the underlying principle of ensuring that sufficient volume is available in the scram discharge headers to acco=modate a scram. ITEM A.2 Revise and implement operating procedures as necessary to provide clear guidance to the licensed operator in the control room regarding when he should initiate the SLCS without obtaining prior supervisory approval. Provide a description of the implemented procedural requirements.
RESPONSE
Operating instructions have been revised to require mandatory initiation of the SLCS whenever the following conditions exist: 1. Five (5) or more adjacent rods not inserted below position 06 and either reactor water level cannot be maintained or suppression pool water temperature limit of 110 F is reached. -_.m-.,,. -,-
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i T 1 '* 2. Thirty (30) or more rods not inserted belc; position 06 and either reactor water level gannot be maintained or suppression pool water temperature limit of 110 F is reached. ITEM A.3 Ensure that procedures exist and are implemented for specifying remedial i action to be taken if water is found in the SDV system at times when it should be free of water. Provide a description of the implemented procedural requirements.
RESPONSE
Procedures have 'been confirmed for specifying remedial action to be taken if a water level is detected in the scram header. The prescribed actions are summarizedd as follows for three separate conditions: 1. Water level 4 1 5". A. Verify scram discharge drain and vent valves open by direct observation. B. Check for inleakage sources; normally expected to be leaking scram discharge valve. 2. Water level > 1.5" but 4 2". A. Decrease load to minimum by reducing recirculation pump speed. B. Scram reactor. 3 Water level > ?". Initiate promptly a controlled shutdown to cold conditions. ITEM A.4 Revise and implement administrative procedures as necessary to ensure that the SLCS key shall be readily available to the licensed operator in the control room. Provide a description of the implemented procedural requirements. REPONSE The SLCS key has been attached to the control panel near the SLCS for prompt use by the operator if necessary. d 0 ,,.--,,---,y,_ ---,mm-- -wy,.. - -,,.. .w,e----c..- ,,m, ,,,ww.- g e.
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j - + s 3-i ITEM A.5 Continue daily monitoring of water levels in all scram discharge volumes until continuous monitoring system (s) (discussed in B.1 below) is (are) installed and operational (this requirement supersedes the requirements of Item 5 of IE Bulletin 80-17 which required daily surveillance for only 6 days).
RESPONSE
Ultrasonic sensors are presently attached to the scram discharge header low points on all three Browns Ferry Nuclear Plant units. These instruments are connected to alarming recorders which are checked approximately every 30 minutes. 1 4 I e O o w. -.5 w------ ,,w,-m-.ry 9,,my, -p-yyn9m, y y%, yep,,,,,--m,.,y-y, ~*.--,7=e9-eg4 --pp-w,- -p w.e yge .T-WY*9f -T " *}}