ML19338F582
| ML19338F582 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 10/02/1980 |
| From: | Stello V NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | BOSTON EDISON CO. |
| Shared Package | |
| ML19338F583 | List: |
| References | |
| IEB-80-17, NUDOCS 8010200631 | |
| Download: ML19338F582 (7) | |
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UNITED STATES OF AMERICA
. NUCLEAR: REGULATORY COMMISSION.
In the 4atter of.
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Docket No.:
50-293
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Bostca Edison _ Company
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- (Pilgrim Nuclear Power Station)
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CONFIRMATORY ORDER I
Boston Edison Company (the " licensee") is the holder of Fac4lity Operating License No. OPR-35 (the "lic~ense") with an expiration date of August 26, 2008 which authorizes operation of the Pilgrim Nuclear Power Station (the " facility").
II On June 28, 1980, during a routine shutdown of the Browns Ferry Nuclear Power Station Unit-3 reactor, a manual scram from approximately 35% power failed.to insert all-of the control rods.
Three scrams were initiated over a period of about 14 minutes to achieve full insertion of all of the control rods.
The control rods which' failed to insert were all located on the east' side-of the reactor core.
Investigation indicated that this was caused by_ water unknowingly accumulating in-the' east side scram discharge volume (SDV).
This accumulation
. reduced the available free' volume for scram water' discharge and. inhibited control
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i 2-rod insertion.~
It is believed that an obstructed vent and/or drain caused the~
accumulation of water. lThis accumulation of water was not detected by the reactor-protection system because it stayed within the SDV headers and did not drain to the scram discharge instrumented volume (SDIV).
On July 2, 1980, a team of NRC Headquarters representatives went to the Browns Ferry site' to gather detailed information on the event and its related considera-tions.
IE Bulletin No. 80-17, "Faiiarc of 76 of 185 Control Rods to Fully Insert During a Scram at a BWR" was issued an July 3, 1980 and requested actions to be taken by allolicensees of operating 3rneral Electric designed Boiling Water Reactors.
Among the actions requestel were the following:
- "1.
Within 3 days from the date sf this Bulletin, perform surveillence tests
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to verify that there is 's significant amount of water in the Scram Dis-
-charge Volume (SDV) a".d-associated piping and that the SDV vent' valves are operable and vent system is free of obstruction."
"3.
At the conclusion of the scram tests and all othe. scrams, verify that all vent' lines in the'SDV are functional.
Verify that there is no significant amount of water in the SDV and associated piping."
"5. -Review and develop surveillance procedures such that scram discharge
-volume'_is monitored daily'for residue water for 6 days and, if results
'are acceptable,Lthe interval may'be extended to 7 days."
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Additional' actions. applicable;to these BWR' facilities'were requested in Supple-tment Nos. 1, 2 and'3 toLIE Bulletin 80-17;.these. supplements were issued on-July 18, July-22 an'd August ~ 22, 1980, respectively.
Specific actions were requested with-~ regard.to the unobstructed-venting and draining of the SDV.
In particular,_ Item B.1 of Supplement I requestsd the following:
"B.
Actions to be Taken by BWR Licensees and Completed by September'1, 1980:
1)
Install a' system to continuously monitor water levels in all scram
' discharge volumes.
Continuous recording and alarm features m'ust be included in the design.
Consideration should be given to use of diverse' level sensors in this (these) system (s).
The design installed ~
should represent the design with the highest level' of reliability compatible with completion of installation by September 1, 1980.
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Provide a written description of the system design to the NRC-Regional
' Office.
If installation by September 1, 1980 is not possible, by August 15, 1980, submit'to the~NRC" Regional Office:
11)
-Documentation in detail why 'the installation cannot be completed -
- by~ September 1, 1980.
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A commitment to a firm sche'dule-for installation.
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A commitment to equipment. changes and/or surveillance requirements in addition to those now-in effect that will provide adequate assurance of SDV operability in the interim until installation is completed."
The licensee responded to this request in Supplement 1 to the Bulletin by letter dated August 14,:1980. -This. response was unacceptable on the basis that it did not-provide adequate assurance that the licensee could maintain scram capability at all times during current operation.
The Bulletin and its Supplements were
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issued to provide such assurance during an interim period of operation until an ultimate resolution is achieved by changes in system design and operating i
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procedures.
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In view of the foregoing considerations the NRC staff has concluded that partic-ular criteria must be satisfied in order to provide adequate justification 'for continued operation.
Criteria applicable to the licensee's facilities are set L
.forth in Section III.
These criteria reflect NRC judgement that continuous mon-itoring of the SDV with appropriate indication and alarm in the control room 1.
to be completed no later.than specified.
Untilithe installation'is complete and operable, surveillance checks of'the SDV shall be made at least once-per shift l
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.whenever the reactor is critical.
LThese matters were the. subject of-the discussions between NRC and licensee-
- representative lMr. LC. : Mathis on ' September 11,.1980. --The discussions provided
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the 'information on which-the. licensee made further commitments to_ satisfy the
- requests.o* the Bulletin and its supplements.
These commitments were' documented
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by letters da'.ed September 16, 1980.and_ September 25, 1980 from the licensee.
In view of the importance of these commitments to safe operation of the facility, dit is appropriate to confirm the licensee's commitments by order.
III Accordingly, pursuant to the Atomic Energy Act of 1954, as amended, and the Commission's regulations in 10 CFR Parts 2 and 50, IT IS HEREBY ORDERED, EFFECTIVE IMMEDIATELY, THAT:
1.
By December 1, 1980, the licensee shall:
a)
Install and make operable a system to continuously monitor water levels all scram discharge volumes (SDV).
b)
The installed system shall provide for level-indication, with an associated alarm, in the contral room, for each.SDV.
This equipment shall provide sufficient information to the reactor operator such that if water accumulates in either SDV the decision about actions
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to.be_taken can be made'in'a. timely fashion from the control room..
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Until~the system described in'III.1 is installed.and operating satis-factorily the licensee shall' increase surveillance of the SDV water level The c.nce per shift 1 surveillance checks shall to at least once per shift.
be.at least 6. hours apart.
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3.
The licensee shall ~ submit a report to the Director, React'or Operations
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' Inspection, Washington,-D.C. 20555 and to the Director of the appropriate NRC Regional Office, confirming installation of the continuous water level-monitoring system, with provisions for indication and alarm in the control room, at the time the installation is completed.
d IV 4
Any person who has an interest affected by this Order may request a hearing ithin twenty-five (25) days of the date of the Order.
Any request for a w
i hearing'will not stay the effectiveness of this Order.
Any request for a q
hearin~g shall be submitted to the Secretary, U.S. Nuclear Regulatory Commission, Washington,-D.C. 20555 with a copy to.the Executive Legal Director at the same address.
A-request'for a~ hearing should describe specifically the minner in which the petitioner's interest is affected by this Order and should address the criteria set forth'in 10 CFR 2.714(d).' If a hearing is requested by a
. person who has-an: interest affected by this Order, the Commission will issue.
an: order designating theLtime and' place of any such' hearing.
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If~a hearing'is held,'the issue to be considered at such a hearing shall be whether the. licensee'should perform the actions required in Part'III of this Order in accordance with the schedule state'd therein.
~0peratien of the facility'on terms' consistent with this Order is'not stayed I'y
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.the pendency-of any proceeding on.the Order.
FOR THE NUCLEAR REGULt. TORY COMMISSION
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VictorStetto,Jy Director Office of. Inspection and Enforcement-Effective Date: 0CT 2 : 1980 Bethesda, Maryland l
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