ML20235H168
| ML20235H168 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 12/24/1986 |
| From: | NIAGARA MOHAWK POWER CORP. |
| To: | Linville J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20235G041 | List: |
| References | |
| FOIA-87-438 NUDOCS 8709300398 | |
| Download: ML20235H168 (4) | |
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December 24, 1986 1
To:
Jim Linville, Chief, Section 2C, DRP From: NMP Resident Office / Project Engineer WEEKLY STATUS REPORT //7 - NINE MILE POINT 2 1.
Plant Status:
NMP-2 experienced two major problems concerning their efforts to complete MSIV work and move on to initial criticality. First, the MSIV preop testing was completed, but MSIV 6B failed the leak testing and later evaluation found a repeat of the scratching and flaking of the ball coating. Second, a major disagreement over the acceptability of the MSIV trip circuit exists between NRR and NMP-2.
The resolution of the MSIV problems remains the critical path for initial criticality. Until these problems are resolved, little other work can be pursued.
The inspection coverage was provided by the resident inspectors, including backshift inspection of MSIV leak testing.
2.
MSIV Status:
MSIV Preoperational Testing was completed on 12/20, and all results were acceptable. However, Type C leak rate testing of all MSIVs was completed on 12/21, and MSIV 6B failed.
The leak rates of acceptable valves ranged from.3 to 2.9 SCFH, while MSIV 6B had a leak rate of 8.9 SCFH (acceptance criteria = 6 SCFH).
Following disassembly of MSIV 6B, NMP-2 found scratching and flaking of the ball coating in the areas above and below the hole.
This repeat of the earlier coating problems represents a major setback to NMP-2's efforts to resolve the problem with adjusted spring force distribution.
Further, a major disagreement between NMP-2 and NRR exists over the acceptability of the MSIV trip logic circuits. The specific design concern relates to the trip circuits for the two solenoid valves on each MSIV actuator and the provision for each of the trip circuits to be powered from either of the two divisions of q RPS power.
Both solenoid valves must be deenergized for the MSIVs to close. During a 12/3 event both divisions of RPS power were inadvertently paralleled out of phase via this MSIV trip circuit, and a reactor scram occurred when all power to RPS was lost. To prevent this paralleling NMP-2 modified the MSIV trip logic circuits to replace two relays, one of which had closed onto the circuit before the other had disengaged, with a single relay with two contacts. NMP-2 believes that this will mechanically pretlude closure of both contacts simultaneously.
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B'709300398 970924 PDR FOIA O//(p WETTERH87-438 PDR
J NRR believes that this design does not meet the electrical 7
independence requirements of RGS 1 6 and 1 75. NMP-2 disagrees.
During a 12/18 Bethesda meeting and a 12/23 conference call, NRR and NMP-2 were unable to reach agreement. Presently, NRR is documenting their position in writing, while NMP-2 reviews alternatives.
3.
Violation of Technical Specifications:
On 12/23 NMP-2 concluded that an unplanned reactor scram had occurred on 12/15 and had not been reported to the NRC, in violation of 10 CFR 50.72.
Specifically, as part of a planned evolution a reactor operator had moved the Reactor Mode Switch from REFUEL to SHUTDOWN and received a scram signal, as expected.
This scram signal was reset, and approximately one minute later an automatic Scram Discharge Volume (SDV) High Level Scram was received. The SDV High Level Scram signal was not in at the time the Mode Switch Scram was reset.
The SDV vent and drain valves open slowly in response to 'he scram reset signal, and the High Level Scram setpoint was reached prior to the SDV drain valver opening. This automatic RPS actuation was not initially determined to be reportable, but a subsequent NMP-2 management review determined otherwise. The Region I Duty Officer and resident inspectors were notified on 12/23.
A similar event had occurred on 11/5, but the corrective actions, a procedure change and instructions to the operators, were not effective in removing the operators' confusion on this topic.
On 12/23 the Fire Protection Supervisor identified that the Reactor Building 2625W Fire Zone Detection System was out of service. The detection system had been out of service since early morning 12/20, and no compensatory action (hourly fire patrol) had been taken, in violation of Technical Specification LCO 3.3.7.8.b.
The licensee irrediately established a fire patrol for the effected area and notified the NRC of the violation. NMP-2 is investigating why the detection system was removed from service without notification of the shift operators.
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Reportable Events:
On 12/18.approximately 4,500 gallons of water were injected into the reactor vessel-by LPCS and RHR A (ECCs Division I) when a common ground lead was lifted for the A and E High Drywell Pressure relays. The common ground had not been identified during the prior electrical isolation checks for the removal of a relay base in an adjacent RCIC circuit.
On 12/22 all three Emergency Diesel Generators (EDGs) were concurrently disabled due to the draining of their respective fuel oil day tanks. Each tank was drained to its storage tank during running of the fuel oil transfer. pump for drawing of a representative monthly sample. When the day tank low level alarm.
was received on each tank, the EDG start circuit logic, by design, automatically locked out any diesel start signal. The EDGs were not required to be operable in the Cold Shutdown Mode, but this event was reported by the licensee to the HQ Duty Officer via the ENS.
5.
Planned Activities:
NMF-2 must resolve the dual problems of MSIV trip circuit acceptability and leakage of MSIV ball valves. On the MSIV trip circuit NRR has the responsibility to describe their concerns in writing to NMP-2. while NMP-2. reviews alternatives.
On the ball valves NMP-2 must establish the cause of failure regarding leakage. Until the scopes of these problems are established, no meaningful schedule for initial criticality can be projected.
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Cumulative Summarv of Significant Events 10/31 - License issued 11/2 - Fuel loading begun 11/5 - IRM reactor trip followed by SDV level reactor trip (ENS) 11/6 - Vital area breached without compensatory measures (ENS) 11/7 - Fuel loading with bypassed SRM (LCO violation) 11/8 - Inoperable RB exhaust rad monitor (LCO violation) 11/9
-.Two APRM reactor trips due to faulty circuit card (ENJJ 11/10 - Inoperable RB exhaust rad monitor (ENS) l_
11/15 - Fuel loading completed i
11/17.- Imbedded conduits without fire seals (LCO violation)
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l 11/20 - Half scram / ESF actuation due to loss of UPS (ENS) l 11/23 - Group 2 scram due to loss of power and APRM testing (ENS) 11/24 - Fire patrol errors found from 11/12 (LCO violation) 11/24 - CRD functional, friction, and scram testing completed 11/25 - SBGTS auto start due to detached jumper (ENS) 11/27 - SBGTS auto start due to rad monitor spike (ENS) 11/28 - SBGTS auto starts (2) due to RB ventilation trips (ENS) 11/30 - Completed installation of MSIV balls and leak tests 12/3 - Scram due to loss of UPS power on MSIV logic flaw (ENS) 12/3 - Group 2 scram due to improper electrical isolation (ENS) 12/8 - SBGTS auto start due to rad monitor spike (ENS) 12/10 - SBGTS design deficiency on heater flow switch (ENS) 12/10 - HPCS starts (3) due to instrument line bumping (ENS) 12/16 - Group 8 PCIS isolation due to wiring check error (ENS) 12/18 - 4,500 F21. injection of RHR and LPCS (ENS) 12/21 - MSIV 6B failed Type C leak test 12/22 - 3 EDGs disabled due to fuel oil draining (ENS)
-12/23 - Unplanned 12/15 reactor scram reported (50.72 violation) 12/23 - Lack of fire patrol discovered (LCO violation) cc: Murley Kane Collins Ebneter Martin Eselgroth Bettenhausen Cook Meyer Starostecki, IE Bernero, NRR Haughey, NRR
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