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Revision as of 21:56, 2 April 2018

U.S. Geological Survey - Response to RAI Dated September 21, 2015, Regarding R-113 License Amendment Request
ML15323A316
Person / Time
Site: U.S. Geological Survey
Issue date: 11/17/2015
From: DeBey T
US Dept of Interior, Geological Survey (USGS)
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME9424
Download: ML15323A316 (18)


Text

Ie .USGSsinefor a changing worldDepartment of the InteriorUS Geological SurveyBox 25046 MS-974Denver CO, 80225November 17, 2015U.S. Nuclear Regulatory CommissionATTIN: Document Control DeskWashington DC 20555SubI: Response to RAI dated September 21, 2015, regarding R-113 license amendment request (TACNo. M E9424)Gentlemen:The attached pages are additional information submitted in response to your Request for AdditionalInformation dated September 21, 2015. Please contact me if you need additional information.Sincerely,Tim DeBeyUSGS Reactor SupervisorI declare under penalty of perjury that the foregoing is true and correct.Executed on 11/17/2015Copy to:Vito Nuccio, Reactor Administrator, MS 911USGS Reactor Operations Committee Response to RAI dated September 21, 2015 concerning a license amendment to the USGS R-113 research reactor license (TAO No. ME9424)Request:2. Your response to RAI No. 2, by letter dated August 28, 2015, provided a proposed TSdefinition of License Area: Rooms 149-152, 154, 157, 158, B10, Bl0B, B11 of Building 15,and Room 2 of Building 10. NUREG-1537, Part 1, Section 9.5, "Possession and Use ofByproduct, Source, and Special Nuclear Material," provides guidance that licensees should"clearly state the materials and areas of the facility requested to be authorized by the reactorlicense. The reactor license and technical specifications also will include regulatoryconditions that apply to the management of such materials." Provide a justification for theproposed TS definition that you provided in your response to RAI No. 2, a markup of theproposed change in the current USGS TSs, and copy of the proposed TS, or justify why thisinformation is not needed.Response: The markup of the proposed change to current USGS TS, and copy of the proposed TS, wasabsent from the initial RAI response, so that is provided in this response.The proposed TS change is the reformatting of page 2 and the addition of Item 7a to the Specifications,as follows:7a. Licensed AreaThe licensed area shall be the following areas on theDenver Federal Center:Building 15, rooms 149 through 152 and room 154Building 15, rooms 157 and 158Building 15, rooms BI0, BlOB, and BIlBuilding 10, room 2 2/06APPENDIX ATECHNICAL SPECIFICATIONS FOR THEU.S. GEOLOGICAL SURVEY TRIGA REACTORDOCKET NO. 50-274The dimensions, measurements, and other numerical values given in thesespecifications may differ from measured values owing to normal construction andmanufacturing tolerances, or normal accuracy of instrumentation.A. Definitions1. ShutdownThe reactor, with fixed experiments in place, shall be considered tobe shutdown (not in operation) whenever all of the followingconditions have been met: a) the console key switch is in the "off"position and the key is removed from the console and under thecontrol of a licensed operator (or stored in a locked storage area);b) sufficient control rods are inserted so as to assure the reactoris subcritical by a margin greater than 0.7% delta k/k cold, withoutxenon; c) no work is in progress involving fuel handling or refuelingoperations or maintenance of the control mechanisms.2. Steady State Mode (SS)Steady state mode shall mean operation of the reactor at power levelsnot to exceed 1 megawatt utilizing the scrams in Table I and theinterlocks in Table II.

-2-3. Pulse ModePulse mode shall mean operation requiring the use of the scrams inTable I and the interlocks in Table II to assure that no more thanone rod is pneumatically withdrawn to produce power pulses.4. Square Wave Mode (SW)Square wave mode shall mean operation of the reactor with the modeselector switch in the square-wave position requiring use of thescrams in Table I and the interlocks in Table II.5. OperableA system or component shall be considered operable *when it is capableof performing its intended functions.6. ExperimentExperiment shall mean: (a) any apparatus, device, or materialinstalled in the core or experimental facilities (except forunderwater lights, fuel element storage racks and the like) which isnot a normal part of these facilities or (b) any operation to measurereactor parameters or characteristics.7. Experimental FacilitiesExperimental facilities shall mean the rotary specimen rack, verticaltubes, pneumatic transfer system, central thimble, and in-poolirradiation facilities.7a. Licensed AreaThe licensed area shall be the following areas on theDenver Federal Center:Building 15, rooms 149 through 152 and room 154Building 15, rooms 157 and 158Building 15, rooms BI0, BlOB, and BIIBuilding 10, room 2

-3-8. Reactor Safety SystemsReactor safety systems shall mean those systems, including theirassociated input circuits, which are designed to initiate a reactorscram.9. Standard Thermocouple Fuel ElementA standard thermocouple fuel element shall contain thermocouplesimbedded in the fuel halfway to the vertical centerline at themidplane of the fuel section and one inch above and below themidplane.B. Reactor Building1. The reactor shall be housed in a closed room designed torestrict leakage. The minimum free volume in the reactor roomshall be 3.1 x 108 cubic centimeters.2. All air or other gas exhausted from the reactor room and fromassociated experimental facilities during reactor operationshall be released to the environment at a minimum of 21 feetabove ground level.3. The concentration of argon 41 in the reactor building stackeffluent air shall be limited to a maximum of 4.8 x 10-6uCi/ml averaged over a year.4. The stack effluent air shall be analyzed quarterly to determinethe isotopic composition of the radionuclides emitted. Thelimit of B.3 above shall apply only to argon 41; limits onconcentrations for other radionuclides shall be as specified in10 CF'R Part 20.C. Reactor Pool and BridgeThe reactor shall not be operated if the pool water level is lessthan 16 feet above the top grid plate. The bulk pool temperatureshall be monitored while the reactor is in operation and the reactorshall be shut down if the temperature exceeds 60°C. The reactor coreshall be cooled by natural convective water flow.

-4-2. The pooi water shall be sampled for conductivity at least weekly.Conductivity averaged over a month shall not exceed 5 micromhos per cm2.This item is not applicable if the reactor is completely defueled andthe pool level is below the W4ater treatment system intake.3. The control console shall have an audible and visual water level alarmthat will actuate when the reactor tank water level is between 12 and 24inches below the top lip of the tank. This water level alarm shall befunctionally tested monthly, not to exceed 45 days between tests. Thisitem is not applicable if the reactor is completely defueled and thepool level is below the water treatment system intake.4. The pool water shall be sampled for pH at quarterly intervals, not toexceed 4 months. The pH level shall be within the range of 4.5 to 7.5for continued operation. This item is not applicable if the reactor iscompletely defueled and the pool level is below the water treatmentsystem intake.D. Reactor Core1. The core shall be an assembly of TRIGA aluminum or stainless steel cladfuel-moderator elements, nominally 8.0 to 12 wt% uranium, arranged in aclose-packed array except for (i) replacement of single individualelements with inoore irradiation facilities or control rods; (2) twoseparated experiment positions in the D through E rings, each occupyinga maximum of three fuel element positions. *The reflector (excludingexperiments and experimental facilities) shall be water or a combinationof graphite and water. The reactor shall not be operated in any mannerthat would cause any stainless-steel clad fuel element to produce acalculated steady state power level in excess of 22 kW. Aluminum cladfuel-moderator elements will only be allowed in the F and G rings of thecore assembly.2. The excess reactivity above cold critical, without xenon, shall notexceed 4.9% delta k/k with experiments in place.3. Fuel temperatures near the core midplane in either the B or C ring ofelements shall be continuously recorded during the pulse mode ofoperation using a standard thermocouple fuel element. The thermocoupleelement shall be of 12 wt% uranium loading if any 12 wt% loaded elementsexist in the core. The reactor shall not be operated in a manner whichwould cause the measured fuel temperature to exceed 735°C in a stainlesssteel clad element in the B ring or 652°C in a stainless steel cladelement in the C ring.4. Power levels during pulse mode operation that exceed 2500 megawattsshall be cause for the reactor to the shut down pending an

-5-investigation by the reactor supervisor to determine the reason for thepulse magnitude. His evaluation and conclusions as to the reason forthe pulse magnitude shall be submitted to the Reactor OperationsCommittee for review. Pulse mode operation will not be resumed untilapproved by the Committee.5. If the reactor is operated in the pulse mode during intervals of lessthan six months, the reactor shall be pulsed semiannually with areactivity insertion of at least 1.5% delta k/k to compare fueltemperature measurements and peak power levels with those of previouspulses of the same reactivity value. If the reactor is not pulsedduring intervals of six months, then for the first pulse after the timeof the last comparative pulse, the reactor shall be pulsed with areactivity insertion of at least 1.5% delta k/k to compare fueltemperature measurements and peak power levels with those of previouspulses of the same reactivity value.6. Each standard fuel element shall be checked for transverse bend andlongitudinal elongation after the first 100 pulses of any magnitude andafter every 500 pulses or every 60 months, whichever comes first. Duringthe first 5 years of aluminum-clad fuel usage, annual fuel transversebend and longitudinal elongation measurements will be made on 20% ofthe aluminum-clad fuel elements that have been in the core at any timeduring that year. The measurement schedule will be controlled suchthat different fuel elements are measured each year for this initial 5-year period. After this initial 5 years of aluminum-clad fuel usage,if no generic problems have been detected, the inspection schedule willrevert back to the standard fuel 60-month schedule.The limit of transverse bend shall be 1/16-inch over the total lengthof the clad portion of the element (excluding end fittings) .The limiton longitudinal elongation shall be 1/10 inch for stainless steel cladelements and a-inch for aluminum clad elements. The reactor shall notbe operated in the pulse mode with elements installed which have beenfound to exceed these limits.

-5 aAny element which exhibits a clad break as indicated by a measurablerelease of fission products shall be located and removed from servicebefore continuation of routine operation. Fuel elements that have beenremoved from service do not need to be checked for transverse bend orlongitudinal elongation.7. Observance of the license and technical specification limits for theGSTR will limit the thermal power produced by any single fuel elementto less than 22 kW if the reactor has at least 100 fuel elements in thecore. Therefore the reactor must have at least 100 fuel elements in thecore if it is to be operated above 100 kW. Operations with less than100 fuel elements in the core will be restricted to a maximum thermalpower of 100 kW.E. Control and Safety Systems1. The standard control rods shall have scram capability and the poisonsection shall contain borated graphite, or boron and its compounds insolid form as a poison in an aluminum or stainless steel clad.

-6-2. The control rods shall be visually inspected at least once every twoyears. If indication of significant distortion or deterioration isfound, the rod(s) will be replaced.3. Only one pulsing control rod may be used in the core. The poisonsection of *this rod shall contain berated graphite or boron and itscompounds in a solid form as a poison in an aluminum or stainlesssteel clad. The pulse rod shall be designed to release and fall uponinitiation of a scram signal. The maximum reactivity worth of therod fully inserted by the drive in relation to fully withdrawn shallbe equal to or less than 2.9% delta k/k.4. A pulse may be initiated only when the reactor is at power less than1 kW. Pulsed reactivi~ty insertion shall not exceed 2.1% delta k/k.5. The minimum shutdown margin (with fixed experiments in place)provided by operable control rods (including the pulse rod) in thecold clean condition, with the most reactivity of the operablecontrol rods fully withdrawn, shall be 0.4% delta k/k.6. The maximum rate of reactivity insertion associated with movement ofa standard rod shall be no greater than 0.2% delta k/k/sec.7. The type and minimum number of safety systems which shall be operablefor reactor operation are shown in Table I.8. The type and minimum number of interlocks which shall be operable forreactor operation are shown in Table II.

-7-9. The reactor instrumentation channels and safety systems for theintended modes of operation as listed in Table I shall be verified tobe operable at least once each day the reactor is operated unless theoperation extends continuously beyond one day, in which case theoperability need only be verified prior to beginning the extendedoperation.10. A licensed reactor operator shall be present during maintenance ofthe reactor control and safety systems.ii. Following maintenance or modification of the control or safetysystems, the associated system shall be verified to be operablebefore the reactor is placed in operation.12. The conditions listed below shall be verified at least once semi-annually, with the exceptioni that if the reactor is operatingcontinuously, the conditions shall be verified after the firstshutdown that occurs more than six months after the previous tests.Those items marked with an

  • are not applicable if the reactor iscompletely defueled, but they must be verified upon startup if morethan six months havepassed after the previous tests.a. *All reactor interlocks are operable.b. *Control element drop times are less than one second (twoseconds for pulse rod) .If drop time is found to be greater thanthis, the rod shall not be considered operable.c. *Power level safety circuits are operable. The circuits willbe tested by the introduction of an electrical signal into thecircuit at a point between the detector and the control system.

-8-d. Ventilation system interlocks are operable.e. *The safety channels indicate the actual power level asdetermined by a thermal power measurement.13. On each day that pulse mode operation of the reactor is planned,. afunctional performance check of the transient (pulse) rod systemshall be performed. Semi-annually, at intervals not to exceed eightmonths, the transient (pulse) rod drive cylinder and the associatedair supply system shall be inspected, cleaned and lubricated asnecessary.F. Radiation Monitoringi. The radiation levels within the reactor laboratory shall be monitoredby at least one area radiation monitor during reactor operation orwhen work is done on or around the reactor core or experimentalfacilities. The monitor shall have a readout and provide a signalwhich actuates an audible alarm. During short periods of repair tothis monitor, reactor operations may continue while a portablegamma-sensitive ion chamber is utilized as a temporary substitute.2. A continuous air monitor with readout and audible alarm shall beoperable in the reactor room when the reactor is operating.3. The alarm set points for the above radiation monitoringinstrumentation shall be verified at least once a week. Thisinstrumentation shall be calibrated at least once a year.G. Fuel Storage1. All fuel elements or fueled devices shall be rigidly supported duringstorage in a safe geometry (keff less than 0.8 under all conditions ofmoderation).2. Irradiated fuel elements and fueled devices shall be stored in anarray which will permit sufficient natural convection cooling suchthat the fuel element or fueled device temperature will not exceeddesign values.

-9-H. Administrative Requirements1. The facility shall be under the direct control of the ReactorSupervisor. He shall be responsible to the Reactor Administrator forsafe operation and maintenance of the reactor and its associatedequipment. He or his appointee shall review and approve allexperiments and experimental procedures prior to their use in thereactor. He shall enforce rules for the protection of personnelagainst radiation.2. A Reactor Operations Committee shall review and approve safetystandards associated with the operation and use of the facility. Itsjurisdiction shall include all nuclear operations in the facility.The Committee shall meet to monitor reactor operations at leastsemi-annually.The Reactor Operations Committee shall be composed of at least fourmembers, appointed by the Director, U.S. Geological Survey, and whoshall be knowledgeable in field relating to nuclear safety. TheReactor Supervisor and a qualified health physicist shall be membersof the Committee. The Committee shall be responsible for determiningwhether a proposed change, test, or experiment would constitute achange in technical specifications or an unreviewed safety questionas defined in 10 CFR Part 50. The Committee shall establish writtenprocedures concerning its activities, quorums, review of experimentsand procedures, and other aspects as appropriate.

3. Written instructions shall be in effect and followed for:a. Testing and calibration of reactor operating instrumentationand control systems, control rod drives, area radiationmonitors and air particulate monitors.b. Reactor startup, routine, operation and reactor shutdown.c. Emergency and abnormal conditions, including evacuation,reentry and recovery.d. Fuel loading or unloading.e. Control rod removal and replacement.f. Maintenance operations which may affect reactor safety.4. Any additions, modifications, or maintenance to the core and itsassociated support structure, the pool structure, and rod drivemechanisms, or the reactor safety system, shall be made and tested inaccordance with the specifications to which the systems or componentswere originally designed and fabricated, or to specificationsapproved by the Reactor Operations Committee as suitable and notinvolving an unreviewed safety question. The reactor shall not beplaced in operation until the affected system has been verified to beoperable.5. The reactor facility emergency plan, emergency procedures andphysical security plan shall be audited by the Reactor OperationsCommittee biennially, with the interval not to exceed 30 months.I. Experiments1. Prior to performing any new reactor experiment, the proposedexperiment shall be evaluated by a person or persons appointed by theReactor Administrator to be responsible for reactor safety. He shallconsider the experiment in terms of its effect on reactor operation

-11-and the possibility and consequences of its failure, including, wheresignificant, consideration of chemical reactions, physical integrity,design life, proper cooling, interaction with core components, andreactivity effects. He shall determine whether, in his judgement, theexperiment by virtue of its nature or design does not constitute asignificant threat to the integrity of the core or to the safety ofpersonnel. Following a favorable evaluation and prior to conductingan experiment, he shall sign an authorization form containing thebasis for the favorable evaluation.2. A favorable evaluation of an experiment shall conclude that failureof the experiment will not lead to a direct failure of a fuel elementor of other experiments.3. No new experiment shall be performed until the proposed experimentalprocedures for that experiment or type of experiment have beenreviewed and approved by the Operations Committee.4. The following limitations on reactivity shall apply to allexperiments:a. The reactivity worth of any individual in-core experiment shallnot exceed $3.00.b. The total, absolute, reactivity worth of in-core experimentsshall not exceed $5.00. This includes the potential reactivitywhich might result from experimental malfunction, experimentflooding or voiding, and removal or insertion of experiments.

-12-c. Experiments having reactivity worths greater than $1.00 shallbe securely located or fastened to prevent inadvertent movementduring reactor operation.5. Experiments containing materials corrosive to reactor components,compounds highly reactive with water, potentially explosivematerials, or liquid fissionable materials shall be doublyencapsulated.6. Explosive materials such as (but not limited to) gun powder,dynamite, TNT, nitro-glycerine, or PETN in quantities greater than 25milligrams shall not be irradiated in the reactor or experimentalfacilities without out-of--core tests which shall indicate that withthe containment provided no damage to the reactor or its componentsshall occur upon detonation of the explosive. Explosive materials inquantities less than 25 milligrams may be irradiated withoutout-of-core tests provided that the pressure produced in theexperiment container upon detonation of the explosive shall be shownto be less than the design pressure of the container.7. Experiment materials, except fuel materials, which could off-gas,sublime, volatize or produce aerosols under (a) normal operatingconditions of the experiment or reactor, (b) credible accidentconditions in the reactor or (c) possible accident conditions in theexperiment shall be limited in activity such that if 100%

-13-of the gaseous activity or radioactive aerosols produced escaped tothe reactor room or the atmosphere, the airborne concentration ofradioactivity averaged over a year would not exceed the limits ofAppendix B of 10 CFR Part 20.8. In evaluating experiments, the following assumptions shall be used:a. If the effluent from an. experiment facility exhaust hrough afilter installation designed for greater than 99% efficiencyfor 0.3 micron particles, the assumption shall be used that atleast 10% of the aerosols produced can escape.b. For materials whose boiling point is above l30oF and wherevapors formed by boiling this material could escape onlythrough an undisturbed column of water above the core, theassumption shall be used that at least 10% of these vapors canescape.9. Each fueled experiment shall be controlled such that the totalinventory of iodine isotopes 131 through 135 in the experiment is nogreater than 1.5 curies and the maximum strontium-90 inventory is nogreater than 5 millicuries.10. If a container fails and releases material which could damage thereactor fuel or structure by corrosion or other means, physicalinspection shall be performed to determine the consequences and needfor corrective action. The results of the inspection and any corrective action taken shall be reviewed by the ReactorOperations Committee and determined to be satisfactory beforeoperation of the reactor is resumed.

-1~5-TABLE IMINIMUM REACTOR SAFETYSYSTEMSOriginatingChannel SetoointMode in which effectiveSS Pulse SW1.2.3.4.5.6.Safety Channel 1Safety Channel 2Scram buttonPreset timerCSC watchdog timerDAC watchdog timer110% of full power110% of full powerManual pushLess than or equalto 15 secondsLoss of refresh signalLoss of refresh signalXXXXXXXXXXXXXXTABLE IIMINIMUM INTERLOCKSMode in which effectiveSS I Pulse ISWAction Prevented1. Control rod withdrawal with neutronlevel less than 10-7% power on thedicital Dower channel.x2.3.4.5.Simultaneous manual withdrawal ofXtwo control rods, including thepulse rod.Simultaneous manual withdrawal of Xtwo control rods excluding thepulse rod.Initiation of pulse above 1 kW. XApplication of air pressure to pulseXrod drive mechanism unless cylinderis fully inserted.6. Withdrawal of any control rod exceptpulse rod.X