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Category:CORRESPONDENCE-LETTERS
MONTHYEARML20217F2121999-10-12012 October 1999 Forwards Proposed Rev to Reed Reactor Facility Emergency Plan,In Response to Internal Audits of Procedure.Changes Are Listed ML20212L0991999-10-0404 October 1999 Advises That Written Exam Scheduled for Wk of 991018. Forwards Administration of Written Exam,Procedures for Administration of Written Exam & Facility Review of Written Exam ML20216H8321999-09-23023 September 1999 Submits Report of TS Violation That Occurred in Sept.Weekly Checklist,Which Contains Several TS Surveillance Items,Was Not Completed within Required Period.Checklist Verifies Two Listed TS Requirements ML20212D4561999-09-20020 September 1999 Informs That NRC Completed Review of Reed College Ltr, ,as Supplemented on 990827 Re Use of Financial Tests & self-guarantee for Providing Reasonable Assurance of Funds for Decommissioning by non-profit Colleges,Univs & Hosps ML20211H0561999-03-10010 March 1999 Expresses Appreciation for Researching Matter Re Ability of Colleges to self-guarantee Decommissioning Costs.Documents in Support of Request That Reed College Be Approved as College Providing self-guarantee of Decommissioning Encl ML20211J0911999-03-10010 March 1999 Provides NRC with Assurance That Reed College Will Fund & Carry Out Required Decommissioning Activities for Triga Mark I Research Reactor If & When Reactor Decommissioned ML20203C8761999-02-0909 February 1999 Forwards Insp Rept 50-288/99-201 on 990125-28.No Violations Noted.Insp Included Selective Exam of Procedures & Representative Records & Interviews with Personnel ML20203A4261999-02-0404 February 1999 Informs of Arrangements Made with Frantz Re Operator Licensing Exam.Written Exam Scheduled for Wk of 990503. Forwards Ref Matl for RO & SRO Licensing Exam,Administration of Written Exam & Procedures & Facility Review of Exam ML20154C6051998-09-29029 September 1998 Forwards Proprietary Revised Reed Reactor Facility Physical Security Plan, Marked Up Copy,Necessitated by Changes in Security Sys & Security Response Organization.Proprietary Encl Withheld ML20153B7701998-09-17017 September 1998 Forwards Amend 6 to License R-112 & Se.Amend Includes Addition of Definition of Allowable Surveillance Time Periods,Increase in Time Period Allowed to Complete Full Insp & Correction & Editorial Changes ML20236S4351998-07-20020 July 1998 Forwards Copy of Recently Approved Regulation in Fr Which Permits Colleges & Univs to self-guarantee Decommissioning Costs If Certain Criteria Are Met.Requests Provision of Criterion to Be Used If School Decides to self-guarantee ML20248M1181998-06-0505 June 1998 Transmits Reactor/Senior Reactor Operator License Certificates for Nine Listed Individuals at Reed College.W/O Encl ML20247K8091998-05-18018 May 1998 Forwards Results of Operator Initial Exam Conducted at Reed College on 980505-07.W/o Encl NUREG-1478, Forwards Initial Exam Rept 50-288/OL-98-01 During Wk of 980504.Exam Conducted IAW NUREG-1478, Non-Power Reactor Operator Licensing Examiner Stds, Rev 11998-05-18018 May 1998 Forwards Initial Exam Rept 50-288/OL-98-01 During Wk of 980504.Exam Conducted IAW NUREG-1478, Non-Power Reactor Operator Licensing Examiner Stds, Rev 1 IR 05000288/19972021998-03-11011 March 1998 Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-288/97-202 ML20216E8411998-03-0909 March 1998 Discusses Arrangements for Administration of Operator Licensing Exams at Reed College Reactor Scheduled for Wk of 980505.In Order to Meet Schedule,Furnish Matl Listed in Encl 1 at Least 60 Days Prior to Exam Date ML20203B9611998-02-18018 February 1998 Responds to NRC Re Violations Noted in Insp Rept 50-288/97-202 on 971215-18.Corrective Actions:Actions Which Would Have Been Taken at Missed Meeting Were Taken at First Meeting of Next Academic Year ML20199C0871998-01-23023 January 1998 Forwards Insp Rept 50-288/97-202 on 971215-18 & Nov.Insp Included Review of Activities Authorized for Facility. Conserns Expressed Re Lack of Attention to Detail ML20199B3221998-01-21021 January 1998 Submits Corrections to Gaseous Release Values in Most Recent Annual Repts,Which Were Inflated by Three Orders of Magnitude.Gaseous Release Data Between 950101 & 971231 Were Recalculated & Correct Values Listed ML20199A8851998-01-16016 January 1998 Forwards RO Certificate for Jm Blaine & SRO Certificates for Sp Cook,Cg Jouseau & GE Vanderbeek at Reed College Nuclear Reactor Facility.W/O Encl ML20199B8781997-11-10010 November 1997 Forwards Results of Operator Initial Licensing Exam Conducted on 971016-17.W/o Encl ML20211P0741997-10-13013 October 1997 Forwards Reed Reactor Facility Annual Rept from Sept 1996- Aug 1997 ML20217H3881997-10-0909 October 1997 Discusses Arrangements Made for Administration of Operator Licensing Exams at Facility During Wk of 971012.Listed Matl Requested in Order to Meet Exam Schedule ML20212C5031997-10-0909 October 1997 Forwards Insp Rept 50-288/97-201 on 970828-29.No Violations Noted.Various Aspects of Safety Program Were Inspected, Including Selective Exams of Procedures & Representative Records & Interview W/Personnel ML20140H7671997-06-11011 June 1997 Informs That Two Licensed Operators Had Performed Activities Without Current Physical.Rept Containing Corrective Actions, Encl ML20141D8741997-06-0303 June 1997 Establishes Irrevocable Standby Ltr of Credit NZS270983 Per Licensee Request.Ltr Effective 970603 & Will Expire 980601 ML20141K2861997-05-23023 May 1997 Forwards Certificates to Tf Boes,Jb Brown,Rm Gaffney, Bd Halbert,Es Olson & Zd Van Hoover,Newly Licensed Individuals.W/O Encls ML20141E4481997-05-19019 May 1997 Forwards Results of Operator Initial Exam on 970505-07. W/O Encl ML20137C1411997-03-20020 March 1997 Responds to Re Decommissioning Funding Assurance Review of Proposed Changes to Reed College Standby Trust Agreement.Proposed Standby Trust Agreement,Acceptable ML20136G0561997-03-10010 March 1997 Requests That Licensee Furnish Matl Listed in Encl 1 at Least 60 Days Prior to Exam Date to P Isaac,In Order to Meet Exam Scheduled for Wk of 970505 ML20136F4841997-03-10010 March 1997 Submits Changes to Standby Trust Agreement ML20135A0141997-02-17017 February 1997 Forwards Reed College Reactor Annual Rept for 950901- 960831 ML20134K4121997-02-11011 February 1997 Responds to Re Revised Reactor Operator Requalification Plan & Concludes That Proposed Changes Meet Applicable Requirements of 10CFR55 & Acceptable ML20149M3001996-12-10010 December 1996 Responds to 961028 Request Re Decommissioning Funding Assurance Review of Proposed Changes to Reed College Ltr of Credit & Standby Trust Agreement.Informs That Proposed Ltr of Credit Satisfies Requirements of 10CFR50.75 & Acceptable ML20134M2711996-11-14014 November 1996 Forwards Rev to Reed Reactor Security Plan Including Physical Changes to Facility,Adding Restroom & Stairs to Temporary Controlled Access & Changing Sequence of Calling in Response to Alarm.Encl Withheld ML20134K4321996-11-13013 November 1996 Forwards Rev to Reed Reactor Facility Requalification Plan Which Explains Change,Paragraph by Paragraph.Rev Changes Requalification Cycle from One Yr Cycle to Two Yr Cycle IAW 10CFR55.59 ML20134K9941996-11-12012 November 1996 Responds to NRC 960910 RAI Concerning Rev to Licensee Emergency Plan ML20129J0511996-10-28028 October 1996 Forwards Drafts of Ltr of Credit & Standby Trust Agreement Re Financial Assurance for Decommissioning of Caption Research Reactor ML20128N4061996-10-11011 October 1996 Forwards Results of Operator Initial Exam Conducted at Licensee Facility on 960924.W/o Encl ML20128Q2551996-10-11011 October 1996 Forwards Intial Exam Rept 50-288/OL-96-03 Administered During Wk of 960923 ML20101J8411996-03-22022 March 1996 Forwards Proposed Rev to Reed Reactor Facility Emergency Plan & Revised Emergency Implementing Procedure,In Response to Change in Telephone Sys ML20149K9801996-02-14014 February 1996 Notifies of Written & Operating Exams Scheduled for Wk of 960422.Forwards Four Encls Re Exam ML20133L0791996-01-15015 January 1996 Forwards RO License Certificates for Listed Individuals. Certificates Provided to All New Operator & Senior Operator Licensees in Recognition of Important Role Licensed Operator Fulfill in Protecting Health & Safety of Public ML20085F7021995-06-0606 June 1995 Forwards Rev to Reed Reactor Facility Emergency Plan & Eip,In Response to NRC Comments on Rev Licensee Submitted Last Yr ML20080H9271995-02-16016 February 1995 Responds to Violations Noted in Insp Rept 50-288/94-01,dtd 950125.Corrective Actions:New Procedure & Planning Calender Should Ensure That Required Training Conducted & Documented Annually ML20078N3591994-11-22022 November 1994 Advises of Decision Not to Operate Reactor at High Temp to Search for Fuel Element Which Experienced Transient Leak in Jan 1994 ML20073J3641994-09-29029 September 1994 Forwards Rev to Reed Reactor Facility Emergency Plan & Emergency Implementation Procedures ML20073E3041994-09-16016 September 1994 Forwards Draft Revised Administrative Procedures.Several Minor Spelling or Grammatical Errors Corrected ML20073E2901994-09-16016 September 1994 Forwards Draft Revised Emergency Plan.Name of Reactor Bay Made Consistent.Refs to Containment Area Changed to Reactor Bay ML20073E2511994-09-16016 September 1994 Forwards Draft Revised Emergency Implementation Procedures, Updating Phone Numbers 1999-09-23
[Table view] Category:INCOMING CORRESPONDENCE
MONTHYEARML20217F2121999-10-12012 October 1999 Forwards Proposed Rev to Reed Reactor Facility Emergency Plan,In Response to Internal Audits of Procedure.Changes Are Listed ML20216H8321999-09-23023 September 1999 Submits Report of TS Violation That Occurred in Sept.Weekly Checklist,Which Contains Several TS Surveillance Items,Was Not Completed within Required Period.Checklist Verifies Two Listed TS Requirements ML20211H0561999-03-10010 March 1999 Expresses Appreciation for Researching Matter Re Ability of Colleges to self-guarantee Decommissioning Costs.Documents in Support of Request That Reed College Be Approved as College Providing self-guarantee of Decommissioning Encl ML20211J0911999-03-10010 March 1999 Provides NRC with Assurance That Reed College Will Fund & Carry Out Required Decommissioning Activities for Triga Mark I Research Reactor If & When Reactor Decommissioned ML20154C6051998-09-29029 September 1998 Forwards Proprietary Revised Reed Reactor Facility Physical Security Plan, Marked Up Copy,Necessitated by Changes in Security Sys & Security Response Organization.Proprietary Encl Withheld ML20203B9611998-02-18018 February 1998 Responds to NRC Re Violations Noted in Insp Rept 50-288/97-202 on 971215-18.Corrective Actions:Actions Which Would Have Been Taken at Missed Meeting Were Taken at First Meeting of Next Academic Year ML20199B3221998-01-21021 January 1998 Submits Corrections to Gaseous Release Values in Most Recent Annual Repts,Which Were Inflated by Three Orders of Magnitude.Gaseous Release Data Between 950101 & 971231 Were Recalculated & Correct Values Listed ML20211P0741997-10-13013 October 1997 Forwards Reed Reactor Facility Annual Rept from Sept 1996- Aug 1997 ML20140H7671997-06-11011 June 1997 Informs That Two Licensed Operators Had Performed Activities Without Current Physical.Rept Containing Corrective Actions, Encl ML20136F4841997-03-10010 March 1997 Submits Changes to Standby Trust Agreement ML20135A0141997-02-17017 February 1997 Forwards Reed College Reactor Annual Rept for 950901- 960831 ML20134M2711996-11-14014 November 1996 Forwards Rev to Reed Reactor Security Plan Including Physical Changes to Facility,Adding Restroom & Stairs to Temporary Controlled Access & Changing Sequence of Calling in Response to Alarm.Encl Withheld ML20134K4321996-11-13013 November 1996 Forwards Rev to Reed Reactor Facility Requalification Plan Which Explains Change,Paragraph by Paragraph.Rev Changes Requalification Cycle from One Yr Cycle to Two Yr Cycle IAW 10CFR55.59 ML20134K9941996-11-12012 November 1996 Responds to NRC 960910 RAI Concerning Rev to Licensee Emergency Plan ML20129J0511996-10-28028 October 1996 Forwards Drafts of Ltr of Credit & Standby Trust Agreement Re Financial Assurance for Decommissioning of Caption Research Reactor ML20101J8411996-03-22022 March 1996 Forwards Proposed Rev to Reed Reactor Facility Emergency Plan & Revised Emergency Implementing Procedure,In Response to Change in Telephone Sys ML20085F7021995-06-0606 June 1995 Forwards Rev to Reed Reactor Facility Emergency Plan & Eip,In Response to NRC Comments on Rev Licensee Submitted Last Yr ML20080H9271995-02-16016 February 1995 Responds to Violations Noted in Insp Rept 50-288/94-01,dtd 950125.Corrective Actions:New Procedure & Planning Calender Should Ensure That Required Training Conducted & Documented Annually ML20078N3591994-11-22022 November 1994 Advises of Decision Not to Operate Reactor at High Temp to Search for Fuel Element Which Experienced Transient Leak in Jan 1994 ML20073J3641994-09-29029 September 1994 Forwards Rev to Reed Reactor Facility Emergency Plan & Emergency Implementation Procedures ML20073E3041994-09-16016 September 1994 Forwards Draft Revised Administrative Procedures.Several Minor Spelling or Grammatical Errors Corrected ML20073E2511994-09-16016 September 1994 Forwards Draft Revised Emergency Implementation Procedures, Updating Phone Numbers ML20073E2901994-09-16016 September 1994 Forwards Draft Revised Emergency Plan.Name of Reactor Bay Made Consistent.Refs to Containment Area Changed to Reactor Bay ML20029C9681994-04-11011 April 1994 Informs That M Pollack,Acting Director of Reed Reactor Facility Resigned Effective 940331.SG Frantz Named Interim Director Effective 940418 ML20115A3411992-10-0909 October 1992 Advises That SS Koblik Now President of Reed College, Replacing Acting President WR Haden on 920824 ML20128D4961992-03-31031 March 1992 Forwards Amend to Recovery Plan Changing Section on Setting Alarm & Failsafe Setpoints for CAM ML20128D5101992-03-30030 March 1992 Forwards Set of Amends to Original Recovery Plan Submitted by Reed College to NRC on 920317,per P Qualls Request ML20128D4771992-03-17017 March 1992 Forwards Rept Constituting Reed College Plan to Evaluate Fuel Cladding Leak at Facility on 911123 ML20115J2651992-01-16016 January 1992 FOIA Request for Documents Re Experimental Nuclear Facility at Reed College Portland,Oregon ML20087A5321991-12-0505 December 1991 Requests Relief from Listed Tech Spec Requirements,Per Confirmatory Action Ltr Re Leak Detected from Fuel Element in Reactor.Recovery Plan Will Be Developed & Submitted to NRC by 920201 ML20079P4381991-11-0505 November 1991 Updates Status of Reactor Operators Licenses at Facility. Lists Operators,Mostly Students,That Have Left Facility & Not Expected to Return to Active Operator Status in Future ML20065S9351990-11-0505 November 1990 Forwards Followup Rept Re Anomalous Behavior of Linear Power Channels on 901008.Caused by Dirt/Corrosion on Mode Switch & Circuit Board Contacts or Incorrect Adjustment of Amplifier. Installation of wide-range Channels Under Consideration ML20056A2621990-07-31031 July 1990 Provides Info Required by 10CFR50.75 Re Assurances That Funds Will Be Available to Decommission Research Reactor. Licensee Will Make Available Senior Reactor Operator to Supervise Decommissioning Over Period of 1 to 2 Yrs ML20043B7211990-05-10010 May 1990 Provides Response to Concerns Raised Re Safety of Facility & Author Serving as Acting Director.Restates Invitation for NRC to Evaluate Concerns ML20043B5591990-05-0101 May 1990 Discusses L Ruby Ltr to NRC Requesting Investigation of Facility,Per Employee Dismissal on 900416.Affirms Confidence in M Pollock,Serving as Acting Director ML20043B5651990-04-17017 April 1990 Advises That Jm Pollock Appointed Acting Director of Facility,Replacing L Ruby,Effective 900417 ML20042F1061990-04-16016 April 1990 Responds to Inquiry Re Gaseous Stack Monitor Calibr.Overhaul of Exhaust Air Sampling Sys Undertaken During 1988 & 1989 & Draft of New Std Operating Procedures for Calibr Gaseous Stack Monitors Worked on W/More Detail ML20043B6091990-04-0707 April 1990 Discusses Concern Re Procedure Used by Director for Latest Calibr of Gaseous Stack Monitor.Monitor Recalibr Last Wk Using Proposed SOPs Rather than Currently Approved Sops.Ltr to Radiation Safety Committee Encl ML20042E5531990-03-30030 March 1990 Advises That Response to NRC Inquiry Re Gaseous Stack Monitor Calibr in Process of Being Written ML20106E3691990-03-0808 March 1990 Forwards Proposed Tech Specs for License R-112,to Change Single Oversight Committee,W/Expertise Which Includes That on Both Present Committees ML20006C3211990-01-17017 January 1990 Responds to 890814 Ltr Re on-the-job Training & Evaluation Concerning Proposed Requalification Plan.Notice to Operators Issued Detailing Policy on Subj Areas,As Alternative to Providing Details as Part of Plan ML20247A4721989-07-0505 July 1989 Forwards Revised Requalification Plan,Approved by Licensee Reactor Operations Committee on 890518 ML20235S8521989-02-17017 February 1989 Forwards Matl & Cover Ltr Mailed to 24 Triga Facilities in Us & Foreign Facilities Re Maint of Control of CRD Switches, Per Recent Telcon ML20116E7901988-06-0606 June 1988 Ack Receipt of NRC Re Recent Insp of Reactor Facilities & Procedures ML20116E8041988-05-24024 May 1988 Lists Requests in Response to Reactor Operator Licensing Exam Conducted on 880516-20 ML20116E8021988-05-24024 May 1988 Requests Listed Actions in Response to Senior Reactor Operator Licensing Exam Conducted on 880516-20 ML20148F6341988-03-25025 March 1988 Forwards Table 1 to Physical Security Plan Omitted from 880311 Submittal.Table Withheld ML20235U1141987-10-0505 October 1987 Notifies That L Ruby Appointed as Director of Reed Reactor Facility,Effective on 870901.JM Pollock Will Continue in Associate Director Position ML20237G9851987-08-18018 August 1987 Advises That L Ruby Appointed Director of Facility Effective 870901.M Pollock Will Continue as Associate Director. Previous Experience of Both Appointees Discussed ML20210F3421987-02-0505 February 1987 Forwards,For Preliminary Informal Review,Ga Technologies,Inc Re Fuel Element Temps in Triga Reactors During Operation & Loca.Proposed Words for Inclusion in Final Draft Tech Specs Sections 2 & 3 Also Encl.Comments Requested 1999-09-23
[Table view] Category:VENDOR/MANUFACTURER TO NRC
MONTHYEARML20235S8521989-02-17017 February 1989 Forwards Matl & Cover Ltr Mailed to 24 Triga Facilities in Us & Foreign Facilities Re Maint of Control of CRD Switches, Per Recent Telcon 1989-02-17
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l February 17, 1989 Mr. T. S. Michaels Standardization and Non-Power Reactor ProjectDirector U.S. Nuclear Regulatory Comnission Washington,'D.C. 20555
Subject:
Notice to- All 'IRIGA Facilities Regarding Maintenance of Control Rod Drive Switches'.
Dear Mr. Michaels,
As per our recent telecon, I have iravigorated all the suggestions you made in our proposed information letter. Enclosed herewith is a copy of the material and cover letter we have mailed to 24 TRIGA facilities in the U.S. and to all foreign and overseas 'IRIGA facilities..
We trust-that the above actions will close the present matter con-cerning stuck control rod switches. We appreciate your'yt- vi and gener-ous help in this matter.
Sincerely, h,30 k , I,M N
Director, Irradiation Services
'IRIGA Group wtw/bb Enclosures 8
AI C O+ ,[
P PO. BOX 85608, SAN DfEGO. CA 92f 38 5608 (619)455 3000 10955 JOHN JAY HOPKINS DRIVE. SAN DIEGO, CA 921211194
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SENE N 'AF M ES.- 1 ,,,: E M yo Tu .
Fax: GJ19) 455-4169 lb February 15, 1989 I
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Subject:
Maintenance of Control Rod Drive Switches
Dear In December 1988,
the Reed College Reactor Facility experienced an incident where a TRIGA reactor control rod switch malfunctioned by sticking in the-UP mode. Although this incident did not present a safety issue, it did involve a safety-related system and, as such, should receive operator attention. For your. information we have prepared the attached memorandum which describes maintenance procedures for control rod drive switches. It is recommended that . these procedures be followed every four or five years to reduce the likelihood that a sticking switch will occur.
~ If you have any questions on these procedures or their implementation, please i contact Bill Hyde at (619) 455-3593.
Sincerely yours,,
h William L. Whittemore, Ph.D.
Director, Irradiation Services i TRIGA Group JTG/lvg Enclosure P0. DOX 85608, SAN DIEGO. CA 92138-5608 (619) 455-3000 10955 JOHN JAY HOPKINS DRIVE, SAN DIEGO. CA 921211194
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j February 7, 1989 MEMORANDUM Frm:: General . Atmics' 'IRIGA Reactor Division >
'Ib:: . All 'IRIGA Research Reactor Far 111 ties
Subject:
Maintenance of Control Rod Drive Switches The unual operation of the 'IRIGA reactor control rods is acccuplished through use of the UP, DCW, and SCRAM switches on the console. The switches are heavy duty, single action units with t apability for internal
,: illumination manufactured by MASTER SPECIALTIES CCEPANY. Fr m the perfor-mance history of these switches in nore than 70 'IRIGA consoles it can be expected that sticking (failure to respond correctly to manual manipula-tion) of one or nore of the switches can be expected during the lifetime'of the. console (10-20 years of use). In the event that sluggish or sticking-behavior is experienced by an operator, a switch should ur& y the mainte-:
nance givcMures set forth below. Preventive maintenance .using' the same ;
givcMares can successfully be performed every four or five years to re-duce the likalih~wi that-s*4 eking switches will occur.
Ihe s*4 eking of the console control switches in no way, affects : the safety circuitry of the console. Power and fuel _ temperature scrams are un- 1 affected by the switch and will perform the safety functions intended.
While a sticking control rod switch (UP, DCW ) does affect a reactor con-trol element and is important for givyer operation of the reactor, it does not dimin4=h the safety of the system.
In the experience of the many 'IRIGA facilities, a. sticking switch can be caused- by two irtr Ent effects. . By far the most usual is caused by the plastic lens which may stick in its frame. The sinple, effective cor-'
rective measure in this case is to remove the lens,- file its edges to re-nove any excess, polish the filed edges, and replace. - Usually this eliminates the sticking problem. .A far less frequent cause of sticking is the am=1ation of foreign material in the switch linkage. We have re-cently received a 1 yvit. fra a TRIGA owner of such a sticking switch; - The
_UP_ switch stuck during the manual withdrawal of a control rod at a power of about 100 watts. The upward movement of this control rod could- only be stopped when the DOR 4 switch was pressed, as designed, but when released, the upward rod movement continued. The power increased from 100 watts to 150 watts at which tine the operator scranned the reactor manually.
The purpose of this information memorandum is to (i) alert all 'IRIGA reactor owners to the possibility of malfunction of a control rod UP or DCM switch due either to an enlarged lens or to the result of arm = lated ,
debris, di.rt, or other foreign material in the switch and (ii) roccamend !
simple, periodic preventive maintenance to keep the switches in proper working order.
.1-._ . . . _ .. . . . . . . . .. .
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Figure 1 is a cutaway drawing of a typical cvukel rod switch shown
" exploded" for clarification. As designed, access to the linkage ==-haniam in these switches requires that the rod control panel on the reactor con-trol console be removed by removing the screws on the console top that hold the panel in place. Removal of the lens portion of the switch, Sections (3) and (4) in Figure 1, frtun the console top does not allow access to the linkage for the recemnended maintenance but does make it possible to file away excessive growth of the plastic lens (surfaces (a) and (b) on Item 4 in Figure 1) should this be necessary. 'Ib reach the linkage, it will be necessary to lift this control rod panel.
Use extreme care when renoving the rod control panel and associated wiring. Do not disassemble the switch assembly (See Note 2 in caption to Figure 1). Each switch assembly should be visually inspected for dirt or other foreign material, espe 4 ally around the switch linkage (Section (1) in Figure 1). Also note any unusual wear of the switch, and visually in-spect the switch wiring. Use u viassed air to gently blow away dust and .
debris between sections (1) and (2), i.e., linkage, and other areas as nec-essary. If cwyrossed air does not cenpletely remove the debris, contact the 'IRIGA Reactor Division at General Atomics for further instructions.
An additional note of caution is offered. Be esp eially careful not to interfere with the wiring to the switches. Many of the interlock circuits have wiring that are attached to these switches. If any soldering is needed, be sure this is performed by an expert tehnir-ian since many wires enter a close region and loose or cold solder joints nust be avoided in this wiring which is essential to the license reqaired interlocks.
Replace the rod control panel after the above inspection and mainte-nance. Inspect the top lens of each switch assembly (sections (3) and (4) in Figure 1) for dirt, debris, unusual wear, misaliemant or binding.
Clean as necessary. Contact the TRIGA Reactor Division at General Atcrnics for further instructions if needed.
After reassembly is emplete carefully check all rod control functions and interlocks as after empletion of any maintenance operation.
Artachment
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Figure 1. EXPIDDED VIEW OF A TYPICAL RCD CCN1ROL SWI'ICH.
Note 1: The surfaces (a) and (b) of the lens (4) scmetines stick in the switch opening.
Note 2 The switch section (1) nust not be removed during the cleaning process. That is, section (1) nnst not be pulled away frczn section 2.
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9 6 January 1989 Af c. e Ross A. Scarano, Director Division of. Radiation Safety and Safeguards U. S. Nuclear Regulatory Commission 1450 Maria Lane, Suite 210 Walnut Creek,- California 94596 5368 Re: Docket 50 286, R ll2 ..
REPORT ON ERRAN1 CONTROL-ROD INCIDENT OF 12/16/88 INIT]AL PROBLEM On the afternoon of December 16, 1988, the reactor was being operated as part of .the requalification- requirements of an RO and for an intended irradiation. -
The reactor checklist was completed at about 13:35 with no indication of any -
problems. The first operation, measuring of the core excess at 5 watts, was '
completed at 13:54 under the observation of the SRO. An inadvertent period scram occurred during this start up but was attributed to the relative inexperience of the operator. At that point, the SRO went into the adjacent radiochemistry lab to finish preparing a sample for irradiation leaving the RO of record and another licensed RO in the control room to practice reactivity manipulations.
The RO had raised the reactor power to 150 W and was manipulating rod up and down buttons to stabilize the reactor at that level. At approximately 14:17, the operator experienced an uninterided power increase, taking the reactor from 150 watts to about 250 watts. This increase was halted and reversed, without the occurrence of a reactor scram, by the operator inserting rods into the core using all three rod down buttons. Then, as the operator began to stabilize the reactor power again, the RO noticed that the Safety Rod was at it's upper extreme despite the fact that the RO believed that all rods had been driven down to correct for the original power increase. At this point, the SRO was notified and the reactor was manually scrammed, pending a review of the operation. When initial evaluation suggested a possible equipment problem, the Director was notified.
Following a review involving the Director (SRO), Associate Director (SRO of record), the RO of record, and the additional RO who had been present at the original incident, the Director concluded that the unexplained power rise was probably operator instigated, but to allow for the possibility of equipment malfunction, he requested the operation to be repeated exactly as originally performed under the careful observation of all present. Beginning at 15:16, the RO took the reactor to 5 watts, measured the core excess, and then proceeded to 150 watts as before. The power was stabilized at that level at 15:40 ',
with no repeat of the power rise. It was noted that this resulted in the Safety Rod position being approxi nately 1/2 to 2/3 of it's fully withdrawn position, far below the level it had achieved during the earlier operation.
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In order to test the hypothesis that the problem was a sticking switch, it was decided to maintain a reactor power of 150 watte, (50% on the 300 watt linear power range) but to raise and lower rods (especially the Safety) alternately by small increments, essentially to continue the operation which had been in progress. After about 15 minutes of uneventful operation of this type, the Director left the Control Room, requesting that the Associate Director directly observe additional testing and that the reactor be immediately scrammed if any additional problems occurred. At 15:52, following a short activation of the Safety Rod "UP" button, the Safety rod continued to rise even though there was no finger on the button. The reactor was thereupon scrammed by the operator. The Director was immediately notified and returned to the control room. I e ordered that no further criticalities would be undertaken until the problem was resolved. From 15:54 until 16:13, the safety rod only was tested by the Associate Director with the other two rods fully inserted in the core to insure that the reactor remained subcritical. Once during this time, the rod continued to rise after a short activation of the up switch. This rise was halted by a quick tap on the "UP" button. The mechanical portions of the switch were removed disassembled, and inspected, as were the mechanical portions of seseral other rod drise switches. All were noted to be dirty; however, due to the lateness of the ' day, it was decided to suspend further testing.
At this point, the Director initiated a discussion on whether an immediately reportable incident had occurred. He concluded in the affirmative, and the NRC, the Provost, the Chairperson of the Reactor Review Committee, and the Oregon Department of Energy were thereupon notified.
ADDITIONAL INVESTIGATIONS 12/17/88 Prior to additional testing, the Associate Director and the Reactor Supervisor completed a review of all past problems with control rod drives by examination of the Mechanical Maintenance Log. Main Log entries for several of these were also examined. One previous occurrence of a similar nature was identified as having occurred on 1/4/74. Mechanical Maintenance Log and Main log entries of that occurrence were located and copied . Phone discussions were held between the Associate Director, who by coincidence had been the operator of record on that date, and the person who had been the Director at the time and who was the individual who recorded the log entry on the final resolution of the problem on 1/8/74. In that case, the problem was traced to mechanical binding in the upper portion of the Shim Rod "UP" {
switch. It was resolved by exchanging this portion of the switch with i identical parts from the unused " Transient Rod" "UP" switch. The log describes testing of the switch successfully approximately 30 times following the exchange, and no further problems with that switch were recorded in the logs reviewed. J A discussion was also held with the chief TRIGA scientist at General Atomic, who advised that similar problems had occurred at G.A. in which mechanical binding of the plastic portion of the switch was found to have been j responsible. The GA official added that such problems have always been easily ;
solved by cleaning the mechanism, sanding off the plastic "UP" label, or )
exchanging the mechanical portion of the switch. GA reported that no problem had eser been documented with the actual switch itself.
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? NOTE:. . GA warned. us that removal and replacement of. the switch itself, should we decide that such is necessary,' must be done- with extreme care since the soldering is very fine, and many of the required reactor: safety systems including SCRAMS : and interlocks are wired through this switch.
TESTING 12/22/88 On :this date, additional testing of the Safety Rod was conducted by the. Associate Director (SRO) and the Reactor Supervisor (SRO). The primary goal was to ascertain, if possible, whether the. problem was mechanical, in the ' upper portion. of the switch, or electrical,' in. the lower portion of the switch. The Safety Rod was tested by repeatedly activating the "UP" and "DOWN" switches.
Tests of the : Safety Rod "UP" switch were tallied. The rod ~ was tested throughout
- the~ range of it's travel. It was tested by both- SRO's. Tests were conducted by' holding the botton' down for long . periods of time, by quickly tapping the ,
button, and everything in- between. The botton was . tested repeatedly by .
pushing it'in the middle as well as on.cach of it's ; edges. After a total of at least 660 activations; of the -button, .the previously demonstrated unintentional rod -
raising had .not been observed. One unusual thing,- however, was observed. At approximately Test #170 with the Safety Rod at a Position of approximately 1260 (2/3 of it's maximum withdrawal distance), the rod faiM to rise when the switch was - depressed.- ' Both SRO's observed. this. occurrence and verified that the source interlock was not activated at the time. This aberration also never repeated.
CONCLUSION AND RESOLUTION 1/6/89
' By this 'date, a letter was on hand from NRC Region ;V reiterating our obligation to notify NRC before attempting any further criticalities. On the basis of the tests reported above, and in consideration of the advice from GA, we concluded that the sticking of. the switch is a rare phenomenon, whose cause is most
. probably in the mechanical portion of the switch. Hence, we removed the UP and DOWN buttons from all 3 rods, and the mechanical linkages. which they-activate. The linkages were cleaned in a pressurized gas stream, which had the effect of removing some solid material which had deposited on their surfaces. Next, in each linkage, lubricant was sprayed between the actuating rod and the bushing through which'it passes. Finally, pieces of dirt and other debris were removed from the housings into which the linkages are inserted.
The switches were then reassembled, and each UP and DOWN button was tested 20 times, with no unusual behavior observed. At this juncture, the Director informed the NRC .by phone of our proposal to resume criticalities. As soon as possible, the incident will be reviewed with all operators, who will. be alerted to watch carefully for any aberrant control-rod behavior, and to scram the reactor promptly and notify the Director if such occurred. The Director will also put the cleaning and lubrication of the control-rod linkages on a regularly scheduled basis.
Sincerely, l
l Y L Lawrence Rubk Professor '
Reactor Director
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