View source for B13926, Provides Response to Investigation Concerning RI-91-A-0137 Issues Concerning Plant Activities

{{Adams
| number = ML20091E151
| issue date = 09/16/1991
| title = Provides Response to Investigation Concerning RI-91-A-0137 Issues Concerning Plant Activities
| author name = Mroczka E
| author affiliation = NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES SERVICE CO.
| addressee name = Hehl C
| addressee affiliation = NRC OFFICE OF INSPECTION &amp; ENFORCEMENT (IE REGION I)
| docket = 05000336
| license number = 
| contact person = 
| document report number = B13926, NUDOCS 9110310097
| package number = ML20091E089
| document type = CORRESPONDENCE-LETTERS, INCOMING CORRESPONDENCE
| page count = 3
}}

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                    .      e. .%. u ~,                                  (?03)(464000 Septem'oer 16, 1991 Docket No. 50-336 B13926 RE: Employee Concerns Mr. Charles V. Behl, Director Division of Reactor Projects U. S. Nuclear Regulatory Commission Region I-475 Allendale Road King of Prussia, Pennsylvania 19406

==Dear Mr. Hehl:==

H111 stone Nuclear Pover Station, Unit No. 2 RI-91-A-0137 In earlier correspondence on this issue ve requested additional time to complete our investigation relating to 1ssue 4.             Our investigation is nov complete and ve provide the following respons1.               Ve have completed our review of identified issues concerning activities at Hillstone Station. As requested in your transmittal letter, our response does not contain any personal privacy, proprietary, or safeguards information. The material contained in this tesponse may be released to the public and placed in the NRC Public Document Room at your discretion. The NRC transmittal letter and our response have received controlled and limited distribution on a "need to know" basis during the preparation of this response.
ISSUEt On June      7,  1991, inadequate tagging vas identified during Vork Order M2-91-05879.       The specific work for which the tagging was incomplete involved adjusting the limit switch for the closed valve position on the o'D"- Condensate Demineralizer inlet          isolation motor operated                 valve (2-CND-170 or H0V23D). The only electrical tag in place vas on the breaker for 2-CND-23D.. Operations records and the P&ID shov that additional electrical tag are required at the outlet valve breaker (2-CND-192 or HOV-37D) as it is interlocked with the inlet valve, at the demineralizer
       = inlet   isolation solenoid bypass valve (2-CND-171 or SOV 221D), and at the limit switch fuses in cubicle 1.
Request:
l l        Please discuss the validity of the above assertions. If any deficiencies in l         tagging, including procedures or implementation are ident.ified,                    please l        provide us with the corrective actions you have taken or vill be taking with regard to these deficiencies.
!   9110310097 911011                          .
t PDR       ADDCK 05000336 P.                      PDR

  .      Mr. n:rics V.11:bl Director U. S. Nuclear Regulatory Commission B13926/Page 2 September 16, 1991' Response                                                                                                                          L The assertion is valid as stated. The P&ID indicates that there is an interlock between the influent and effluent valves. During the performance                                                        -
of the work for Automated Vork order (AVO) M b91-05870 the need for an additional tag on MOV-37D was identified by Operations Department personnel and- a tag was hung. Additional investigation into the electrical circuits has revealed that one contact from the 42 rotor is used for remote interlocking purposes. From the vendor diagrams of panel CUB 1 (Cubicle 1) it was determined that power for the limit switch contact is provided from Fuse F-25 in the panel. Inadvertently, this fuse was not pulled as part of the tagging for AVO M2-91-05870. However, by using normal precautions associated with vorking on energized 120 volt circuits the job was completed safely.
Because the existing drawings were,                                            in some cases, hard to read, draving changes have been initi' 2ed by the Engineering Department to clearly indicate the multiple power sources for the contacts at issue and power feeds from the fuses in CUB 1.                                         The fuses in CUB 1 have been labeled to make them easier to identify.
Having identified this interlock, and the power feed from Fuse F-25, the necessary additional tagging can nov be employed for future maintenance activities. Information concerning the power feeds from the fuses in panel CUB 1 which was sent to the Operations Department vill also be sent to the Maintenance Depart.nent by the Engineering Department so that the need for e.dditfor.a1 tagging can be specified in future maintenance activities.
After our review and evaluation of this issue, ve find that this issue did not present any indication of a compromise of nuclear safety.                                                             Ve      -
appreciate.the opportunity to respond and explain the basis of our actions.
Please contact my staff if~there are further questions on any of these matters.
Very truly yours, NORTHEAST NUCLEAR ENERGY COMPANY E. J.)[r6cika Seni6r Vice President f
cc    V. J. Raymond, Senior Resident Inspector, Millstone Unit Nos.                                                  1, 2, and 3 E. C. Venzinger, Chief,                                     Projects Branch No. 4, Division of Reactor Projects E. M. Kelly, Chief, Reactor Projects Section 4A J. T. Shedlosky, NRC, Millstone Nuclear Power Station
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