ML15160A023

Texas A&M University - Response to U.S. NRC Request for Additional Information Regarding the Renewal of Facility Operating License No. R-83

ML15160A023
Person / Time
Site:	05000128
Issue date:	06/05/2015
From:	McDeavitt S M Texas A&M Univ
To:	Geoffrey Wertz Document Control Desk, Office of Nuclear Reactor Regulation
References
2015-0036, TAC ME 1584
Download: ML15160A023 (83)

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3I TEXAS A&M ENGINEERING EXPERIMENT STATIONNUCLEAR SCIENCE CENTERJune 5, 2015 2015-0036 Document Control DeskATTN: Geoffrey WertzU.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Subject:

Response to U.S. NRC Request for Additional Information Regarding theRenewal of Facility Operating License No. R-83 for the Nuclear Science CenterTRIGA Reactor (TAC No. ME 1584), from the Texas A&M University System,Texas Engineering Experiment

Station, Nuclear Science Center Reactor (NSCR,License No. R-83, Docket 50-128)To Whom It May Concern:The Texas A&M University System, Texas Engineering Experiment Station (TEES), NuclearScience Center (NSC, License No. R-83) operates a LEU, 1MW, TRIGA reactor under timelyrenewal.

In December, 2003 the NSC submitted a Safety Analysis Report (SAR) as part of thelicense renewal process.

In December, 2005 a conversion SAR (Chapter

18) was submitted resulting in an order to convert from the U.S. NRC. In July 2009, the NSC submitted an updatedSAR, dated June 2009, to the U.S. NRC. This updated 2009 version of our SAR incorporated the information from the conversion SAR and the startup of the new LEU reactor core. On May6, 2015 the U.S. NRC submitted a Request for Additional Information as a part of the reviewprocess.

Attached is our reply to this request.If you have any questions, please contact Dr. Sean McDeavitt or Mr. Jerry Newhouse at 979-845-7551.

TEL. 979.845.7551 I FAX 979.862.2667 nsc.tamu.edu 1095 Nuclear Science Rd. I 3575 TAMU I College Station, TX 77843-3575 I declare under penalty of perjury that the foregoing is true and correct.

Executed on June 5,2015.Dr. Sean M. McDeavitt

Director, Nuclear Science CenterAssociate Professor of Nuclear Engineering Department of Nuclear Engineering Dwight Look College of Engineering Texas A&M University mcdeavitt@tamu.edu Xc: 2.1 l/Central FileDuane Hardesty, USNRC Project Manager Appendix ATOFACILITY LICENSE NO. R-83DOCKET NO. 50-128TECHNICAL SPECIFICATIONS ANDBASESTEXAS ENGINEERING EXPERIMENT STATIONNUCLEAR SCIENCE CENTER (NSC)JUNE 2015Page I 1Texas Engineering Experiment Station NSC TECHNICAL SPECIFICATIONS 1 Introduction 1.1 ScopeThis document constitutes the Technical Specifications for the Facility License No. R-83 asrequired by 10 CFR 50.36 and supersedes all prior Technical Specifications.

This documentincludes the "bases" to support the selection and significance of the specifications.

Each basis isincluded for information purposes only. They are not part of the Technical Specifications, andthey do not constitute limitations or requirements to which the licensee must adhere.1.2 FormatThese specifications are formatted to NUREG-1537 and ANSI/ANS 15.1-2007.

1.3 Definitions

ALARAThe ALARA program (As Low as Reasonably Achievable) is a program for maintaining occupational exposures to radiation and release of radioactive effluents to the environs as low asreasonably achievable.

AuditAn audit is a quantitative examination of records, procedures, or other documents afterimplementation from which appropriate recommendations are made.ChannelA channel is the combination of sensors, lines, amplifiers, and output devices that are connected for the purpose of measuring the value of a parameter.

Channel TestA channel test is the introduction of a signal into the channel to verify that it is operable.

Channel Calibration A'channel calibration is an adjustment of the channel such that its output corresponds, withacceptable

accuracy, to known values of the parameter that the channel measures.

Calibration shall encompass the entire channel, including equipment actuation, alarm, or trip and shall bedeemed to include a channel test.Page 12Texas Engineering Experiment Station NSC Channel CheckA channel check is a qualitative verification of acceptable performance by observation ofchannel behavior.

This verification, where possible, shall include comparison of the channel withother independent channels or systems measuring the same variable.

Confinement Confinement is an enclosure of the overall facility that is designed to limit the release ofeffluents between the enclosure and its external environment through controlled or definedpathways.

Control RodA control rod is a device fabricated from neutron-absorbing material or fuel, or both, that is usedto establish neutron flux changes and to compensate for routine reactivity losses. A control rodcan be coupled to its drive unit allowing it to perform a safety function when the coupling isdisengaged.

Regulating Control RodThe regulating rod is a low-worth control rod used primarily to maintain an intended power levelthat need not have scram capability.

Its axial position may be varied manually or by the servocontroller.

Shim Safety Control RodA shim safety rod is a control rod having an electric motor drive and scram capabilities.

It shallhave a fueled follower section.Transient Control RodThe transient rod is a pneumatically driven control rod with scram capabilities that is capable ofproviding rapid reactivity insertion to produce a pulse.Core Configuration The core configuration includes the number, type, or arrangement of fuel elements, reflector

elements, and regulating/shim-safety/transient rods occupying the core grid.Core Lattice PositionThe core lattice position is that region in the core (approximately 3" x 3") over a grid-plug hole.A fuel bundle, an experiment, or a reflector element may occupy the position.

Page 13Texas Engineering Experiment Station NSC Excess Reactivity Excess reactivity is that amount of reactivity that would exist if all control rods were moved tothe maximum reactive condition from the point where the reactor is exactly critical (keff= 1) atreference core conditions.

Experiment An operation,

hardware, or target (excluding devices such as detectors, foils, etc.) that isdesigned to investigate non-routine reactor characteristics, or that is intended for irradiation within the pool, or in a beam port or irradiation facility.

Hardware rigidly secured to a core orshield structure so as to be a part of its design to carry out experiments is not normallyconsidered an experiment.

Secured Experiment A secured experiment is any experiment, experiment

facility, or component of an experiment that is held in a stationary position relative to the reactor by mechanical means. The restraining forces must be substantially greater than those to which the experiment might be subjected byhydraulic, pneumatic,

buoyant, other forces that are normal to the operating environment of theexperiment, or by forces that can arise as a result of credible malfunctions.

Unsecured Experiment An unsecured experiment is any experiment or component of an experiment that does not meetthe definition of a secured experiment.

Movable Experiment A movable experiment is one where it is intended that all or part of the experiment may bemoved in or near the core or into and out of the reactor while the reactor is operating.

Experimental Facilities Experimental facilities shall mean beam ports, including extension tubes with shields, thermalcolumns with shields, vertical tubes, through tubes, in-core irradiation

baskets, irradiation cell,pneumatic transfer

systems, and in-pool irradiation facilities.

Experiment Safety SystemsExperiment safety systems are those systems, including their associated input circuits, which aredesigned to initiate a scram for the primary purpose of protecting an experiment or to provideinformation for operator intervention.

Page I4Texas Engineering Experiment Station NSC Fuel BundleA fuel bundle is a cluster of two, three, or four fuel elements and/or non-fueled elements securedin a square array by a top handle and a bottom grid plate adapter.

Non-fueled elements shall befabricated from stainless steel, aluminum, boron, or graphite materials.

Fuel ElementA fuel element is a single TRIGA fuel rod of LEU 30/20 type.Instrumented Fuel Element (IFE)An instrumented fuel element is a special fuel element in which one or more thermocouples areembedded for the purpose of measuring the fuel temperatures during operation.

LicenseThe written authorization, by the U.S. NRC, for an individual or organization to carry out theduties and responsibilities associated with a personnel

position, material, or facility requiring licensing.

LicenseeA licensee is an individual or organization holding a license.LEU CoreAn LEU core is an arrangement of TRIGA-LEU fuel in a reactor grid plate.Limiting Safety System Setting (LSSS)The limiting safety system setting is the fuel element temperature, which if exceeded, shall causea reactor scram to be initiated, preventing the safety limit from being exceeded.

Measured ValueA measured value is the value of a parameter as it appears on the output of a channel.OperableOperable means a or systi:fi is capable of performing its intended function.

Operating Operating means a component or system is performing its required function.

Page 15Texas Engineering Experiment Station NSC Operational Core -Steady StateA steady state operational core shall be an LEU core which meets the requirements of theTechnical Specifications.

Operational Core -PulseA pulse operational core is a steady state operational core for which the maximum allowable pulse reactivity insertion has been determined.

Pool Water Reference Operating LevelThe pool water reference operating level is 10 inches below the top of the pool wall. This levelis designed to prevent pool water from rising above the top of the liner.Protective ActionProtective action is the initiation of a signal or the operation of equipment within the reactorsafety system in response to a parameter or condition of the reactor facility having reached aspecified limit.Pulse ModePulse mode operation shall mean any operation of the reactor with the mode selector switch inthe pulse position.

Reactivity Worth of an Experiment The reactivity worth of an experiment is the value of the reactivity change that results from theexperiment being inserted into or removed from its intended position.

Reactor Console SecuredThe reactor console is secured whenever all control rods have been verified to be fully insertedand the console key has been removed from the console.Reactor Operating The reactor is operating whenever it is not secured or shutdown.

Reactor OperatorA Reactor Operator is an individual who is licensed to manipulate the controls of a reactor.Page 16Texas Engineering Experiment Station NSC Reactor Safety SystemsReactor safety systems are those systems, including their associated input channels, which aredesigned to initiate automatic reactor protection or to provide information for initiation ofmanual protective action.Reactor SecuredThe reactor is secured when:Either(1) There is insufficient moderator available in the reactor to attain criticality or there isinsufficient fissile material present in the reactor to attain criticality under optimumavailable conditions of moderation and reflection; Or(2) All of the following conditions exist:(a) All control rods are fully inserted; (b) The console key switch is in the "off' position and the key is removed from theconsole lock;(c) The reactor is shutdown; (d) No work is in progress involving core fuel, core structure, installed control rods,or control rod drives unless the control rod drives are physically decoupled fromthe control rods;(e) No experiments are moved or serviced that have, on movement, a reactivity worthexceeding

$1.00.Reactor ShutdownThe reactor is shut down if it is subcritical by at least $1.00 in the reference core condition withthe reactivity worth of all installed experiments included.

Reference Core Condition The condition of the core when it is at ambient temperature (cold) and the reactivity worth ofxenon is less than $0.01.Page 17Texas Engineering Experiment Station NSC Reportable Occurrence Any of the following events is a reportable occurrence:

(1) Operation with actual safety system settings for required systems less conservative thanthe LSSS specified in the Technical Specifications; (2) Operation in violation of a Limiting Condition of Operation listed in Section 3 unlessprompt remedial action is taken as permitted in Section 3;(3) Operation with a required reactor or experiment safety system component in aninoperative or failed condition which renders or could render the system incapable ofperforming its intended safety function.

If the malfunction or condition is caused duringmaintenance, then no report is required; (4) An unanticipated or uncontrolled change in reactivity greater than $1.00. Reactor tripsresulting from a known cause are excluded; (5) Abnormal and significant degradation in reactor fuel or cladding, or both, coolantboundary, or confinement boundary; and(6) An observed inadequacy in the implementation of either administrative or procedural

controls, such that the inadequacy causes or could have caused the existence ordevelopment of an unsafe condition with regard to reactor operations.

ReviewA review is a qualitative examination of records, procedures, or other documents prior toimplementation from which appropriate recommendations are made.Safety ChannelA safety channel is a channel in the reactor safety system.Safety LimitSafety limits for nuclear reactors are limits upon important process variables that are found to benecessary to reasonably protect the integrity of certain of the physical barriers that guard againstthe uncontrolled release of radioactivity.

For the Texas A&M NSC TRIGA reactor the safetylimit is the maximum fuel element temperature that can be permitted with confidence that nodamage to any fuel element cladding will result.Scram TimeScram time is the elapsed time between the initiation of a scram signal and the instant that theslowest scrammable control rod reaches its fully inserted position.

Page I8Texas Engineering Experiment Station NSC Senior Reactor OperatorA Senior Reactor Operator is an individual who is licensed to direct the activities of reactoroperators.

Such an individual is also a reactor operator.

Shall, Should and MayThe word "shall" is used to denote a requirement; the word "should" to denote arecommendation; and the word "may" to denote permission, neither a requirement nor arecommendation.

Shutdown MarginShutdown margin is the minimum shutdown reactivity necessary to provide confidence that thereactor can be made subcritical by means of the control and safety systems, starting from anypermissible operating condition.

This margin is determined assuming that the most reactivescrammable rod and any non-scrammable rods are fully withdrawn, and that the reactor willremain subcritical by this calculated margin without any further operator action.Steady State ModeSteady state mode of operation shall mean operation of the reactor with the mode selector switchin the steady state position.

Surveillance Intervals The maximum surveillance intervals are provided for operational flexibility and the averagesurveillance intervals should be maintained over the long term.Annually

-an interval not to exceed 15 months.Biennially

-an interval not to exceed 30 months.Monthly -an interval not to exceed 6 weeks.Quarterly

-an interval not to exceed 4 months.Semiannually

-an interval not to exceed 7.5 months.Weekly -an interval not to exceed 10 days.True ValueThe true value is the actual value of a parameter.

Unscheduled ShutdownAn unscheduled shutdown is any unplanned shutdown of the reactor caused by actuation of thereactor safety system, operator error, equipment malfunction, or a manual shutdown in responseto conditions that could adversely affect safe operation.

It does not include shutdowns that occurduring testing or check out operations.

Page 19Texas Engineering Experiment Station NSC 2 Safety Limit and Limiting Safety System Setting2.1 Safety Limit-Fuel Element Temperature Applicability This specification applies to the temperature of the reactor fuel.Objective The objective is to define the maximum fuel element temperature that can be permitted withconfidence that no damage to the fuel element cladding will result.Specification The temperature in a stainless steel-clad TRIGA LEU fuel element shall not exceed 2100 'F(1 150'C) under any conditions of operation.

BasisThe most important safety limit for a TRIGA reactor is fuel element temperature.

This parameter is well suited as a single specification because it can be measured directly with a thermocouple.

A loss in the integrity of the fuel element cladding could arise from a buildup of excessive pressure if the fuel element temperature exceeds the temperature safety limit. The fuel elementtemperature and the ratio of hydrogen to zirconium in the fuel-moderator material determine themagnitude of the pressure buildup.

The mechanism for the pressure buildup is the dissociation ofhydrogen from the zirconium hydride moderator that has been blended with uranium to form thefuel mixture encased within the fuel element cladding.

The temperature safety limit for the LEU fuel element is based on data which indicates that theinternal stresses within the fuel element, due to hydrogen pressure from the dissociation of thezirconium

hydride, will not result in compromise of the stainless steel cladding if the fueltemperature is not allowed to exceed 2100°F (1 150°C) and the fuel element cladding is watercooled.Page I 10Texas Engineering Experiment Station NSC 2.2 Limiting Safety System SettingApplicability This specification applies to the scram setting that prevents the safety limit from being reached.Objective The objective is to prevent the safety limit from being reached.Specification The limiting safety system setting shall be 975°F (525°C) as measured in an instrumented fuelelement (IFE). The IFE shall be located adjacent to the central bundle with the exception of thecomer positions.

BasisThe limiting safety system setting (LSSS) is a temperature that, if exceeded, will cause a reactorscram to be initiated preventing the safety limit from being exceeded.

The temperature safety limit for LEU fuel is 2100°F (1150°C).

Due to various errors inmeasuring temperature in the core, it is necessary to arrive at a LSSS for the fuel element safetylimit that takes into account these measurement errors. The results of analysis provided in SAR13.3 Evaluation of LSSS for NSC LEU 30/20 Fuel indicate that a LSSS temperature of 975°F(525°C) is appropriate.

In the pulse mode of operation, the above temperature limiting safety system setting will apply.However, the temperature channel will have no effect on limiting peak powers generated becauseof its relatively long time constant (seconds) as compared with the width of the pulse(milliseconds).

In this mode, however, a temperature trip will act to reduce the amount of energygenerated in the entire pulse transient by cutting the "tail" off the energy transient in the eventthe pulse rod remains stuck in the fully withdrawn position.

Page I 11Texas Engineering Experiment Station NSC 3 Limiting Conditions for Operation 3.1 Reactor Core Parameters 3.1.1 Steady State Operation Applicability This specification applies to the energy generated in the reactor during steady state operation.

Objective The objective is to ensure that the fuel temperature safety limit will not be exceeded duringsteady state operation.

Specification The reactor power level shall not exceed 1.0 megawatt (MW) during steady state operation.

BasisCalculations show that reactor operations with a pool temperature of 60'C will not risk reachinga fuel temperature greater than the LSSS, or a DNBR of unity for 1MW steady state. (Response to U.S. NRC Request for Additional Information, Review of The Fuel Pool Temperature on FuelTemperature, submitted November 13, 2014).3.1.2 Pulse Mode Operation Applicability This specification applies to the peak temperature generated in the fuel as the result of a pulseinsertion of reactivity.

Objective The objective is to ensure that respective pulsing will not induce damage to the reactor fuel.Specification The reactivity to be inserted for pulse operation shall not exceed that amount which will producea peak fuel temperature of 1526°F (830'C).

In the pulse mode the pulse rod shall be limited bymechanical means or the rod extension physically shortened so that the reactivity insertion willnot inadvertently exceed the maximum value.Page 1 12Texas Engineering Experiment Station NSC BasisThe pulsing limit of 830'C will be translated to a reactivity insertion limit for each specific core.The peaking factors from the thermocouple element to the hottest spot in the core must becalculated for each core configuration that is to be used. Temperature would then be measuredfor small pulse insertions.

The initial core calibration in 2006 established the maximum allowable pulse insertion to be$1.91. Any subsequent pulse insertion change shall only be made after core recalibration andfollowing approval by the NSC staff.3.1.3 Shutdown MarginApplicabiliy This specification applies to the reactivity condition of the reactor and the reactivity worth ofcontrol rods and experiments.

They apply for all modes of operation.

Obiective The objective is to ensure that the reactor can be shutdown at all times and to ensure that the fueltemperature safety limit will not be exceeded.

Specification The reactor shall not be operated unless the shutdown margin provided by control rods is greaterthan $0.50 with:1. Irradiation facilities and experiments in place and the total worth of all non-secured experiments in their most reactive state,2. The highest worth control rod and the regulating rod fully withdrawn, and3. The reactor in reference core condition.

BasisThe value of the shutdown margin ensures that the reactor can be shut down from any operating condition even if the highest worth control rod should remain in the fully withdrawn position.

Since the regulating rod is not scrammable, its worth is not used in determining the shutdownreactivity.

Page I 13Texas Engineering Experiment Station NSC 3.1.4 Reactor Core Cotfiguration Applicability This specification applies to the configuration of the fuel and in-core experiments.

Objective The objective is to ensure that provisions are made to restrict the arrangement of fuel elementsand experiments so as to provide assurance that excessive power densities will not be produced.

Specification

1. Control rods shall not be manually removed from the core unless the core has beenshown to be subcritical, and shutdown margin requirements met, with those control rodsremoved.2. Core lattice positions shall not be vacant except for positions on the periphery of the coreassembly while the reactor is operating.

Water holes in the inner fuel region shall belimited to single rod positions.

Vacant core positions not on the periphery shall containexperiments or an experimental facility to prevent accidental fuel additions to the core.3. The instrumented fuel element, if serving as the Limiting Safety System sensor, shall belocated adjacent to the central bundle with the exception of the comer positions.

Basis1. Manipulation of core components will be allowed only when a single manipulation cannot result in inadvertent criticality.

2. Vacant core positions containing experiments-or an experimental facility will preventaccidental fuel additions to the reactor core. They will be permitted only on the periphery of the core or a single rod position to prevent power peaking in regions of high powerdensity.3. SAR 13.3.1 Steady State Mode provides an evaluation of the LSSS in steady state mode.It states in part, "The location of the fuel cluster containing the instrumented fuel elementshall be chosen to be as close as possible to the hottest fuel element in the core." Thelocation(s) as close as possible to the hottest fuel element in the core are those adjacent tothe central bundle with the exception of the comer positions.

These adjacent positions are: C5 east, D4 north, E5 west, D6 south.Page1 14Texas Engineering Experiment Station NSC 3.1.5 Reactor Fuel Parameters Applicability This specification applies to all fuel elements.

Obiective The objective is to maintain the integrity of the fuel elements' cladding.

Specification

1. The reactor shall not be operated knowingly with damaged fuel, except for the purpose oflocating damaged fuel elements.

2. A fuel element shall be considered damaged and must be removed from the core if:a. In measuring the transverse bend, the bend exceeds 0.125 inch over the length ofthe cladding, orb. In measuring the elongation, its length exceeds its original length by 0.125 inch,orc. A clad defect exists as indicated by release of fission products, ord. A visual inspection reveals bulges, gross pitting or corrosion.

3. The bumup of the uranium-235 in the UZrH fuel matrix shall not exceed 50 percent ofthe initial concentration.

BasisGross failure or obvious visual deterioration of the fuel is sufficient to warrant declaration of thefuel as damaged.

The elongation, bend, and bum-up limits are values that have been foundacceptable to the U.S. NRC (NUREG-1537).

3.1.6 Maximum Excess Reactivity Applicability This specification applies to the reactivity condition of the reactor and the reactivity worths ofcontrol rods and experiments and applies for all modes of operation.

Obiective The objective is to ensure that the reactor can be shutdown at all times.Page I 15Texas Engineering Experiment Station NSC Specification The maximum reactivity in excess of reference core condition shall not exceed 5.5% Ak/k($7.85).BasisThe nominal total rod worth is $16.00 (SAR 4.5.3.2 and historic data). Subtracting the shutdownmargin ($0.50),

the nominal rod worth of the most reactive rod ($4.00),

and adding the allowedtotal reactivity worth for all experiments

($5.00) gives a result of $16.50.The specification of $7.85, although over-constraining the reactor system, helps ensure that thelicensee's operational power densities, fuel temperatures, and temperature peaks are maintained within the evaluated safety limits. The specified excess reactivity allows for power coefficients of reactivity, xenon poisoning, most experiments, and operational flexibility.

3.2 Reactor Control and Safety Systems3.2.1 Reactor ChannelsApplicability This specification applies to the information that must be available to the reactor operator duringreactor operation.

Objective The objective is to require that sufficient information is available to the operator to ensure safeoperation of the reactor.Specification The reactor shall not be operated in the specific mode of operation unless the channels listed inTable 1 are operable.

Table 1: Channels Required for O erationMinimum Number Operating ModeChannel Operable S.S. PulseFuel Element Temperature

1. X XLinear Power Level I XLog Power Level I XIntegrated Pulse Power I XPool Water Temperature I X XPage I 16Texas Engineering Experiment Station NSC BasisFuel temperature displayed at the control console gives continuous information on thisparameter, which has a specified safety limit. The power level monitors ensure that the reactorpower level is adequately monitored for both steady state and pulsing modes of operation.

Thespecification on reactor power level indications are included in this section, since the power levelis related to fuel temperature.

The specification on pool water temperature indication is includedin this section to allow monitoring in support of TS 3.8.3 and 4.8.3.3.2.2 Reactor Safety Systems and Interlocks Applicability This specification applies to the reactor safety system channels and interlocks.

Objective The objective is to specify the minimum number of reactor safety system channels and interlocks that must be operable for safe operation.

Specification The reactor shall not be operated unless the safety circuits and interlocks described in Tables 2aand 2b are operable.

However, any single safety channel or interlock may be inoperable whenthe reactor is operating for the purpose of performing a channel check, channel test, or channelcalibration.

If any required safety channel or interlock becomes inoperable while the reactor isoperating, for reasons other than identified in this TS, then the channel shall be restored tooperation within 5 minutes or the reactor shall be immediately shutdown.

Table 2a: Safety Channels Required for Operation Safety Channel Number Function Operating ModeOperable S.S. PulseFuel Element Temperature I Scram _ 975°F X XHigh Power Level 2 Scram _< 1.25MW XConsole Scram Button I Manual Scram X XHigh Power Level Detector Power Scram on loss of supply voltage X -SupplyPreset Timer I Transient Rod Scram 15 seconds or -less after pulsePool Water Temperature 1 Manual scram if temperature reaches X X60 CPage I 17Texas Engineering Experiment Station NSC Table 2b: Interlocks Required for Operation Safety Channel Number Function Operating ModeOperable S.S. PulsePrevents withdrawal of the ShimLog Power I Safety Control Rods at an indicated X -log power of less than 4x103 W.Log Power I Prevents pulsing of the Transient Rod -when log power is above I kW.Prevents application of air to theTransient Rod Position I Transient Rod unless the Transient XRod is fully inserted.

Prevents Shim Safety and Regulating Shim Safety and Regulating Rod Position I Control Rod withdrawal during a Xpulse.Prevents application of air to thePulse Stop Electro-Mechanical Interlock I Transient Rod unless the mechanical Xpulse stop is installed.

BasisDuring period of maintenance, surveillance, calibration, and repair, true signals generated by thereactor may be required.

This operation is allowable provided all other TS conditions are met.Safety Channels Required for Operation

1. The fuel temperature and high power level scrams provide protection to ensure that thereactor can be shutdown before the safety limit on fuel element temperature will beexceeded.

2. The manual console scram allows the operator to shut down the system if an unsafe orabnormal condition occurs.3. In the event of failure of the power supply for a high power level safety detector, operation of the reactor without adequate instrumentation is prevented.

4. The preset timer ensures that the reactor power level will reduce to a low level afterpulsing.5. A manual scram is a sufficient response because pool water temperature is a slow-changing parameter.

It is surveyed frequently enough to give time for an operator torespond.Interlocks Required for Operation Page I 18Texas Engineering Experiment Station NSC

1. The interlock to prevent startup of the reactor at power levels less than 4 x 10-3 W, whichcorresponds to approximately 2 cps, ensures that sufficient neutrons are available forproper indication.

2. The interlock to prevent pulsing at powers above I kW ensures that the magnitude of thepulse will not cause the fuel element temperature safety limits to be exceeded.

3. The interlock to prevent application of air to the transient rod unless the cylinder is fullyinserted is to prevent pulsing of the reactor in steady state mode.4. The interlock to prevent the withdrawal of the shim safeties or regulating rod in the pulsemode is to prevent the reactor from being pulsed while on a positive period.5. The interlock to prevent application of air to the transient rod unless the mechanical pulsestop is installed prevents a reactor pulse of sufficient worth to exceed the temperature safety limit.3.2.3 Minimum Number of Operable Scrammable Control Rods and Scram TimeApplicability This specification applies to the minimum number of operable scrammable control rods in thecore, where operable is specified in terms of maximum scram time from the instant that anySCRAM signal is initiated.

Objective The objective is to achieve prompt shutdown of the reactor to prevent fuel damage.Specification During operation, all control rods shall be operable.

For scrammable control rods, the scram timemeasured from the instant a SCRAM signal is initiated to the instant that the slowest scrammable rod reaches its fully inserted position shall not exceed 1.2 seconds.

During core manipulations, i.e. core loading and unloading, all installed control rods shall be operable.

BasisThis specification ensures that the reactor will be promptly shutdown when a scram signal isinitiated.

Experience and analysis have indicated that for the range of transients anticipated for aTRIGA reactor, the specified scram time is adequate to ensure the safety of the reactor.3.3 Confinenient Page 1 19Texas Engineering Experiment Station NSC 3.3.1 Operations that Require Confinement Applicability This specification applies to the area housing the reactor and the ventilation system controlling that area.Objective To provide restrictions on radioactive airborne material releases into the environment.

Specificationi Confinement of the reactor building shall be required during the following operations:

1. Reactor operating;

2. Movement of irradiated fuel elements or fuel bundles;3. Core or control rod work that could cause a change in reactivity of more than one dollar;or4. Handling of radioactive materials with the potential for airborne release.1 For periods of maintenance to the central exhaust system, entry doors to the reactor building shall remain closed except formomentary opening for personnel entry or exit. The central exhaust system shall not remain inoperable during periods ofmaintenance for more than one hour.BasisThis specification describe when the central exhaust system shall operate to control any releaseof radioactive material in the confinement building.

3.3.2 Equipment to Achieve Confinement Applicability This specification applies to the equipment and controls needed to provide confinement of thereactor building.

Obiective The objective is to ensure that a minimum of equipment is in operation to achieve confinement as specified in Section 3.3.1 and that the control panel for this equipment is available for normaland emergency situations.

Specification 2Page 20Texas Engineering Experiment Station NSC

1. The minimum equipment required to be in operation to achieve confinement of thereactor building shall be the central exhaust system, which consists of the central exhaustfan, isolation

louvers, and associated duct work.2. The central exhaust system shall be considered operating when it creates a minimum of0.1 inch of water negative pressure at the sample point in the central exhaust system ductwork.3. Controls for establishing the operation of the central exhaust system during normal andemergency conditions shall be available in the Emergency Support Center.4. The central exhaust system shall be isolated automatically by alarm level signals from thestack particulate, or stack gas (xenon) facility air monitor.2 During periods of maintenance to the central exhaust system, entry doors to the reactor building shall remain closed exceptfor momentary opening for personnel entry or exit. The central exhaust fan system shall not remain inoperative duringperiods of maintenance for more than one hour.Basis1. Operation of the central exhaust fan will achieve confinement of the reactor buildingduring normal and emergency conditions when the controls for air input are set such thatthe central exhaust fan capacity remains greater than the amount of air being delivered tothe reactor building.

The exhaust fan has sufficient capacity to handle extra air intake tothe building during momentary opening of doors. Isolation of the central exhaust fan forperiods of less than one hour is for operability verification during weekly ventilation checks. This limit provides enough time to complete these checks.2. Negative pressure in the confinement building mitigates leakage of unmonitored airbornematerial to the environment.

3. The control panel for the central exhaust system provides for manual selection of airinput to the reactor building and the automatic or manual selection of air removal.

The airsupply and exhaust systems work together to maintain a small negative pressure in thereactor building.

These controls are available in the emergency support center foraccessibility during emergency conditions.

4. An automatic isolation of the central exhaust system will mitigate leakage ofunmonitored airborne material to the environment.

3.4 Ventilation SystemThe LCO for Ventilation System is covered by TS 3.3.2 Equipment to Achieve Confinement 3.5 Radiation Monitoring Systems and Effluents Page 121Texas Engineering Experiment Station NSC 3.5.1 Radiation Monitoring Applicability This specification applies to the radiation monitoring information that must be available to thereactor operator during reactor operation, movement of irradiated fuel elements or fuel bundles,conduct of core or control rod work that could cause a change in reactivity of more than onedollar, or handling of radioactive materials with the potential for airborne release.Obiective The objective is to ensure that sufficient radiation monitoring information is available to theoperator to ensure safe operation of the facility.

Specification Reactor operation, movement of irradiated fuel elements or fuel bundles, conduct of core orcontrol rod work that could cause a change in reactivity of more than one dollar, or handling ofradioactive materials with the potential for airborne release shall not be conducted unless theradiation monitoring channels listed in Table 3 are operable, displays and alarms are operable inthe control room, and displays are operable in the Emergency Support Center.Table 3: Radiation Monitoring Channels Required for Operation 3Radiation Monitoring Channels Function NumberReactor Bridge ARM Monitor radiation levels withinthe reactor bayStack Particulate Monitor Monitor radiation levels in the(FAM Ch. 1) exhaust air stackStack Gas Monitor Monitor radiation levels in the(FAM Ch. 3) exhaust air stackBuilding Particulate Monitor Monitor radiation levels within(FAMI Ch. 4) the reactor bayStack Xenon Monitor Monitor radiation levels in the(FAMI Ch. 5) exhaust air stack3 When a required channel becomes inoperable, operations may continue only if a portable gamma-sensitive ion chamber isutilized asa temporary substitute, provided that the substitute can be observed by the reactor operator, can be installed within 1hour of discovery, and is not used longer than one week. If two of the above monitors are not operating, operations shall cease.BasisThe radiation monitors provide information to operating personnel of any impending or existingdanger from radiation so that there will be sufficient time to evacuate the facility and take thenecessary steps to prevent the spread of radioactivity to the environment.

Page ]22Texas Engineering Experiment Station NSC 3.5.2 Argon-41 Discharge LimitApplicability This specification applies to the concentration of Argon-41 (41 Ar) that may be discharged fromthe TRIGA reactor facility.

Obiective The objective is to ensure that the health and safety of the public is not endangered by thedischarge of 41Ar from the TRIGA reactor facility.

Specification The total annual discharge of 41Ar into the environment shall not exceed 30 Ci per year.BasisIf the 30 Ci is assumed to be released continuously over one year, then the Ar-41 concentration at the point of discharge, which is the top of the stack, is 2.5 x 10-7 ýtCi/ml.

This concentration isdiluted br a factor of 200 to get the Ar-41 concentration at the site boundary 1.0 x 10-9 iiCi/ml.1.0 x 10 ýiCUml corresponds to a dose of 12.6 mrem.3.6 Limitations on Experiments 3.6.1 Reactivity LimitsApplicability This specification applies to the reactivity limits on experiments installed in the reactor and itsexperimental facilities.

Obiective The objective is to prevent damage to the reactor or excessive release of radioactive materials incase of failure of an experiment.

Page 123Texas Engineering Experiment Station NSC Specification The reactor shall not be operated unless the following conditions governing experiments exist:1. The absolute reactivity worth of any single, movable or unsecured experiment shall beless than $1,2. The reactivity worth of any secured experiment shall be less than $2, and3. The sum of the absolute reactivity of all experiments, shall be less than $5.Basis1. This specification is intended to ensure that the worth of a single unsecured experiment will be limited to a value such that the safety limit will not be exceeded if the positiveworth of the experiment were suddenly inserted.

This does not restrict the number ofunsecured experiments adjacent to or in the reactor core except by reactivity worth andthe requirements of these TS.2. The maximum worth of a single secured experiment is limited so that its removal fromthe reactor in reference core condition will not result in the reactor achieving a powerlevel high enough to exceed the fuel element temperature safety limit. Since experiments of such worth must be secured, its removal from the reactor operating at full power wouldresult in a relatively slow power increase such that the reactor protective systems wouldact to prevent high power levels from being attained.

3. This limit poses a restriction on the total absolute reactivity of experiments being run atany given time to prevent excessive positive and negative reactivity effects fromexperiments.

3.6.2 Material Limitations Applicability This specification applies to experiments installed in the reactor and its experimental facilities.

Objective The objective is to prevent damage to the reactor or excessive release of radioactivity by limitingmaterials quantity and radioactive material inventory of the experiment.

Page 124Texas Engineering Experiment Station NSC Specification I. Explosive materials in quantities inclusively between 25 milligrams and 5 pounds (TNT-equivalent) shall not be allowed within the reactor building except as noted below in TS.Explosive materials in quantities greater than 5 pounds (TNT-equivalent) shall not beallowed within the reactor building.

Irradiation of explosive materials shall be restricted as follows:a. Explosive materials in quantities greater than or equal to 25 milligrams (TNT-equivalent) shall not be irradiated in the reactor pool. Explosive materials inquantities up to 25 milligrams (TNT-equivalent) may be irradiated provided thepressure produced upon detonation of the explosive has been calculated and/orexperimentally demonstrated to be less than half the design pressure of thecontainer;

b. Explosive materials in quantities greater than or equal to 25 milligrams (TNT-equivalent) shall only be allowed in the lower research level and laboratory

building, excluding the heat exchanger room and demineralizer room;c. Irradiation of explosive materials in quantities greater than or equal to 25milligrams (TNT-equivalent) shall be permitted only in the neutron radiograph facility;

d. Explosive materials in quantities greater than or equal to 5 pounds (TNT-equivalent) shall not be irradiated in experimental facilities; ande. Cumulative exposures for explosive materials in quantities greater than or equal12to 25 milligrams (TNT-equivalent) shall not exceed 10 n/cM2 for neutron or 25Roentgen for gamma exposures.

2. Corrosive materials used in a reactor experiment shall be double encapsulated.

Exceptions may only be made if a detailed analysis and/or prototype testing with smallamounts of materials demonstrates that the experiment presents negligible risk.Basis1. This specification is intended to prevent damage to the reactor or reactor safety systemsresulting from failure of an experiment involving explosive materials.

a. This specification is intended to prevent damage to the reactor core and safetyrelated reactor components located within the reactor pool in the event of failureof an experiment involving the irradiation of explosive materials.

Limitedquantities of less than 25 milligrams (TNT-equivalent) and proper containment ofsuch experiment provide the required safety for in-pool irradiation provided thatthe pressure produced upon detonation of the explosive has been calculated and/orPage 125Texas Engineering Experiment Station NSC experimentally demonstrated to be less than half the design pressure of thecontainer.

(Regulatory Guide 2.2)b. This specification is intended to prevent damage to vital equipment by restricting the quantity and location of explosive materials within the reactor building.

Explosives in quantities exceeding 25 milligrams (TNT-equivalent) are restricted from areas containing the reactor bridge, reactor console, pool water coolant andpurification

systems, and reactor safety related equipment.

(Amendment No. 7 toFacility License No. R-83)c. This specification supports the same goal as the previous specification.

Theneutron radiograph facility was analyzed and shown to be able to withstand anexplosion of the described quantity.

(Amendment No. 7 to Facility License No. R-83)d. The failure of an experiment involving the irradiation of up to 5 pounds (TNT-equivalent) of explosive material in an experimental facility located external tothe reactor pool structure will not result in damage to the reactor or the reactorpool containment structure.

e. This specification is intended to prevent any increase in the sensitivity ofexplosive materials due to radiation damage during exposures.

See: Kaufman J.V.R. (Jul. 29, 1958). The Effect of Nuclear Radiation onExplosives.

Proceedings of the Royal Society of London. Series A., Mathematical and Physical

Science, Vol. 246 (No. 1245, A Discussion on the Initiation andGrowth of Explosion in Solids);Urizar M.J., Loughran E.D., Smith L.C. (Jan. 01, 1960). A Study of the Effects ofNuclear Radiation on Organic Explosives; andAmendment No. 7 to Facility License No. R-83.2. This specification is intended to prevent damage to the reactor or reactor safety systemsresulting from failure of an experiment involving corrosive materials.

3.6.3 Failures and Malfunctions Applicability This specification applies to experiments installed in the reactor and its experimental facilities.

Objective The objective is to prevent damage to the reactor or excessive release of radioactive materials inthe event of an experiment failure.Page 126Texas Engineering Experiment Station NSC Specification

1. Experiment materials, except fuel materials, which could off-gas,

sublime, volatilize, orproduce aerosols under (a) normal operating conditions of the experiment or reactor, (b)credible accident conditions in the reactor, or (c) possible accident conditions in theexperiment shall be limited in activity such that if 100% of the gaseous activity orradioactive aerosols produced escaped to the reactor building or the atmosphere, theairborne concentration of radioactivity averaged over a year would not exceed the limit ofAppendix B of 10CFR20.2. In calculations pursuant to 1) above, the following assumptions shall be used:a. If the effluent from an experimental facility exhausts through a holdup tank thatcloses automatically on high radiation level, at least 10% of the gaseous activityor aerosols produced will escape;b. If the effluent from an experimental facility exhausts through a filter installation designed for greater than 99% efficiency for 0.3 micron particles at least 10% ofthese vapors can escape; orc. For materials whose boiling point is above 130°F and where vapors formed byboiling this material can escape only through an undisturbed column of waterabove the core, at least 10% of these vapors can escape.3. If a capsule fails and releases material that could damage the reactor fuel or structure bycorrosion or other means, removal and physical inspection shall be performed todetermine the consequences and need for corrective action. The results of the inspection and any corrective action taken shall be reviewed by the NSC Director or his designated alternate and determined to be satisfactory before operation of the reactor is resumed.Basis1. This specification is intended to reduce the likelihood that airborne activities in excess ofthe limits of Appendix B of 10 CFR 20 will be released to the atmosphere outside thefacility boundary of the NSC.2. These assumptions are used to evaluate the potential airborne radioactivity release due toan experiment failure.3. Operation of the reactor with reactor fuel or structure damage is prohibited to avoidrelease of fission products.

Potential damage to reactor fuel or structure must be broughtto the attention of the NSC Director or his designated alternate for review to ensure safeoperation of the reactor.Page I 27Texas Engineering Experiment Station NSC 3.7 As Low As Reasonable Achievable (ALARA) Radioactive Effluents ReleasedApplicability This specification applies to the measures required to ensure that the radioactive effluents released from the facility are in accordance with ALARA criteria.

Objective The objective is to constrain the annual radiation exposure to the general public resulting fromoperation of the reactor to a level as low are reasonably achievable below the constraints listed in10 CFR 20.1101.Specification

1. In addition to the radiation monitoring specified in Section 5.5, an environmental radiation monitoring program shall be conducted to measure the integrated radiation exposure in and around the environs of the facility on a quarterly basis.2. The annual radiation exposure (dose) to the public due to reactor operation shall notexceed the limits defined in 10 CFR 20.1301.

The facility perimeter shall be monitored toensure this specification is being met.3. In the event of a fission product leak from a fuel rod or an airborne radioactive releasefrom a sample being irradiated, as detected by the facility air monitor (FAM), the reactorshall be shut down until the source of the leak is located and eliminated.

However, thereactor may continue to be operated on a short-term basis, as needed, to assist indetermining the source of the leakage.4. The facility liquid effluents collected in the holdup tanks shall be discharged inaccordance with 10 CFR 20.2003 "Disposal by release into sanitary sewerage."

Theliquid effluent shall also meet local sanitary sewer discharge requirements.

BasisThe simplest and most reliable method of ensuring that ALARA release limits are accomplishing their objective of minimal facility-caused radiation exposure to the general public is to actuallymeasure the integrated radiation exposure in the environment on and off the site.Page 128Texas Engineering Experiment Station NSC 3.8 Primary Coolant Conditions 3.8.1 Prinma. Coolant PurityApplicability This specification applies to the quality of the primary coolant in contact with the fuel cladding.

Objective The objectives are to minimize the possibility for corrosion of the cladding on the fuel elementsand to minimize neutron activation of dissolved materials.

Specification

1. The reactor shall not be operated for a period exceeding two weeks if the two weekaveraged conductivity of the bulk pool water is higher than 5 x 10-6 mhos/cm.2. The concentrations of radionuclides in the bulk pool water shall be no higher than thevalues presented for water in 10 CFR Appendix B to Part 20 Table 2.BasisA small rate of corrosion continuously occurs in a water-metal system. In order to limit this rate,and thereby extend the longevity and integrity of the fuel cladding, a water cleanup system isrequired.

Experience with water quality control at many reactor facilities has shown thatmaintenance within the specified limits provides acceptable control.By limiting the concentrations of dissolved materials in the water, the radioactivity of neutronactivation products is limited.

This is consistent with the ALARA principle, and tends todecrease the inventory of radionuclides in the entire coolant system, which will decreasepersonnel exposure during maintenance and operations.

3.8.2 Primary Coolant Level and Leak Detection Applicability This specification applies to the water level that must be in the pool and requirements for leakdetection for reactor operation.

Obiective The objective is to ensure proper shielding and cooling of the reactor and the ability to detectleaks.Page I 29Texas Engineering Experiment Station NSC Specification

1. The reactor shall not be operated if the pool level is below 3 feet from the reference operating level.2. The reactor shall not be operated if the pool level unexpectedly drops one foot from itsoperating level.3. The pool level alarm shall initiate an alarm signal in the control room and at acontinuously monitored off-site facility if the pool level is lower than 3 feet from itsreference operating level.Basis1. The intake to the diffuser system is approximately 18 feet above the core and 8.5 feetbelow the reference operating level. Setting this level as the specification will bothensure the availability of the diffuser system, and provide more than adequate shielding and cooling for the reactor.2. An unexpected one foot drop from the operating pool level, whatever level that may be,indicates leakage.3. An operable pool level alarm that provides an off-site alarm will ensure propernotification if a low pool level or significant unexpected change occurs.3.8.3 Primary Coolant Temperature Applicability This specification applies to the maximum allowable primary coolant temperature.

Objective The objective is to maintain fuel temperature less than the LSSS, and to maintain the departure of nucleate boiling ratio (DNBR) greater than unity, and to limit any degradation of the reactorsystems.Specification The reactor shall not be operated when pool temperature exceeds 600 C.BasisCalculations showthat reactor operations with a pool temperature of 60 C will not risk reachinga fuel temperature greater than the LSSS, or a DNBR of unity. In fact, a conservative calculation predicts a DNBR of 1.54. (Response to U.S. NRC Request for Additional Information, Reviewof The Fuel Pool Temperature on Fuel Temperature...

dated November 13, 2014). For reactorPage 130Texas Engineering Experiment Station NSC pulses, the NSC already accounts for pool temperature.

As described in the SAR (4.5.13 PulseOperation

-NSC -BOL, Measured),

the NSC calculates peak core temperature.

Thetemperature in this calculation is in 'C. Ambient fuel temperature is already included in pulsecalculations.

Page I 31Texas Engineering Experiment Station NSC 4 Surveillance Requirements Applicability This specification applies to the surveillance requirements of any system related to reactor safety.Objective The objective is to verify the proper operation of any system related to reactor safety.Specification Surveillance requirements may be deferred during reactor shutdown (except TS 4.1.5, 4.2.3, 4.5,4.8.1, and 4.8.2); however, they shall be completed prior to reactor startup unless reactoroperation is required for performance of the surveillance.

Such surveillance shall be performed as soon as practical after reactor startup.

Scheduled surveillance, which cannot be performed with the reactor operating, may be deferred until a planned reactor shutdown.

Possible to Defer Required prior toTS During Shutdowns?

operations?

1. 4.1.1 Steady State Operation Yes Yes2. 4.1.2 Pulse Mode Operation Yes Yes3. 4.1.3 Shutdown Margin Yes Yes4. 4.1.4 Core Configuration Limitation Yes Yes5. 4.1.5 Reactor Fuel Elements No N/A6. 4.1.6 Maximum Excess Reactivity Yes Yes7. 4.2.1 Reactor Channels Yes Yes8. 4.2.2 Reactor Safety Systems andInterlocks Yes Yes9. 4.2.3 Minimum Number of OperableScrammable Control Rods and ScramTime No N/A10. 4.3 Confinement Yes Yes11. 4.5 Radiation Monitoring Systemsand Effluents No N/A12. 4.6 Experiments Yes Yes13. 4.8.1 Primary Coolant Purity No N/A14. 4.8.2 Primary Coolant Level and LeakDetection No N/A15. 4.8.3 Primary Coolant Temperature Yes YesAny additions, modifications, or maintenance to the central exhaust system, the core and itsassociated support structure, the pool or its penetrations, the pool coolant system, the rod drivemechanism, or the reactor safety system shall be made and tested in accordance with thespecifications to which the systems were originally designed and fabricated or to specifications Page 132Texas Engineering Experiment Station NSC approved by the Reactor Safety Board. A system shall not be considered operable until it issuccessfully tested.BasisThis specification relates to changes in reactor systems, which could directly affect the safety ofthe reactor.

As long as changes or replacements to these systems continue to meet the originaldesign specifications, then it can be assumed that they meet the presently accepted operating criteria.

4.1 Reactor Core Parameters 4.1.1 Steady State Operation Applicability This specification applies to the surveillance requirement of the power level monitoring channels.

Objective The objective is to verify that the maximum power level of the reactor meets the licenserequirements.

Specification A channel.

calibration shall be made of the power level monitoring channels by the calorimetric method annually.

BasisThe power level channel calibration will ensure that the reactor will be operated at the properpower level.4.1.2 Pulse Mode Operation Applicability This specification applies to the surveillance requirements for operation of the reactor in thepulse mode.Objective The objective is to verify that operation of the reactor in the pulse mode is proper and safe and todetermine if any significant changes in fuel characteristics have occurred.

Page 1 33Texas Engineering Experiment Station NSC Specification The reactor shall be pulsed semiannually to compare fuel temperature measurements and corepulse energy with those of previous pulses of the same reactivity value. The reactor shall not bedeclared operational for pulsing until such pulse measurements are performed and aredetermined to be acceptable.

BasisThe reactor is pulsed at suitable intervals to make a comparison with previous similar pulses andto determine if changes in fuel or core characteristics are taking place.4.1.3 Sh utdown MarginApplicability This specification applies to the surveillance requirement of control rod calibrations andshutdown margin.Obiective The objective is to verify that the requirements for shutdown margins are met for operational cores.Specification The reactivity worth of each control rod and the shutdown margin shall be determined annuallyand following changes in the core, in-core experiments, or control rods.BasisThe reactivity worth of the control rods is measured to ensure that the required shutdown marginis available and to provide an accurate means for determining the reactivity worth of experiments inserted in the core. Experience with TRIGA reactors gives assurance that measurement of thereactivity worth on an annual basis is adequate to ensure no significant changes in the shutdownmargin.4.1.4 Core Configuration Limitation Applicability This specification applies to the surveillance requirements for core configuration.

Objective The objective is to verify the core is in a safe, reviewed, and approved configuration.

Page 134Texas Engineering Experiment Station NSC Specification Each core configuration change shall be determined to meet the requirements of TS 3.1.4 prior tothe core loading.BasisThe requirements of TS 3.1.4 ensure acceptable safety analysis is complete for a coreconfiguration, as well as prevent accidental fuel damage, fuel addition, or criticality events.4.1.5 Reactor Fuel ElementsApplicability This specification applies to the surveillance requirements for the fuel elements.

Objective The objective is to verify the continuing integrity of the fuel element cladding and to ensure thatno fuel damage has occurred.

Specification

1. The following fuel elements shall be inspected visually for damage or deterioration andmeasured for length and bend annually:

a. At least four elements which occupy the highest pulse temperature positions in thecore,b. At least one-fifth of the fuel elements used in operation of the reactor over theprevious inspection year,c. The four elements (a) above may be included in the inspection of the fuelelements of (b) above, andd. Over a 5 year period every fuel element used in operation of the reactor shall beinspected.

2. If any element is found to be damaged, the entire core will be inspected.

BasisThe frequency of inspection is based on the parameters most likely to affect the fuel cladding ofa pulsing reactor operated at moderate pulsing levels and utilizing fuel elements whosecharacteristics are well known. Experience has shown that temperature is the major contributor to fuel damage. Inspection of four fuel elements which occupy the highest pulse temperature positions in the core provides surveillance for detection of the most probable fuel elementPage 135Texas Engineering Experiment Station NSC damage should it occur. Inspection of one-fifth of the elements used in operation of the reactorprovides surveillance of the lower temperature elements and over a five year period provides forinspection of all elements.

4.1.6 Maximum Excess Reactivity Applicability This specification applies to the surveillance requirements of reactor excess reactivity.

Objective The objective is to verify that requirements on excess reactivity are met for operational cores.Specification The excess reactivity shall be determined annually and following changes in the core, in-coreexperiments, or control rods for which the predicted change in reactivity exceeds the absolutevalue of the specified shutdown margin.BasisThe excess reactivity of the core is measured to ensure that during all states of operation criticality can be maintained for licensed operational limits. With the accumulation of fissionproduct poison buildup and fissile material burnup, excess reactivity must be available for powertransients and maintaining criticality.

4.2 Reactor Control and Safety Systems4.2.1 Reactor ChannelsApplicability This specification applies to the surveillance requirements for reactor channels.

Objective The objective is to verify the condition and operability of system components directly related tochannels that measure key reactor parameters.

Specification A channel test of each of the reactor channels for the intended mode of operation, as identified inTable 1, shall be performed before each day's operation or before each operation extending morethan one day.Page 136Texas Engineering Experiment Station NSC BasisChannel tests will ensure that the safety system channels are operable on a daily basis or prior toan extended run.4.2.2 Reactor Safety Systems and Interlocks Applicability This specification applies to the surveillance requirements for measurements, tests, andcalibrations of the control and safety systems.Objective The objective is to verify the performance and operability of the systems and components thatare directly related to reactor safety.Specification

1. A channel test of each of the reactor safety system channels and interlocks for theintended mode of operation, as identified in Table 2, shall be performed before eachday's operation or before each operation extending more than one day.2. A channel calibration of the fuel element temperature channels shall be performed semiannually.

BasisChannel tests will ensure that the safety system channels are operable on a daily basis or prior toan extended run. If the period between operations extends beyond a year, then the annual channeltest requirement will ensure operability.

4.2.3 Minimum Number of Operable Scrammable Control Rods and Scram TimeApplicability This specification applies to the surveillance requirements for reactor control systems.Obiective The objective is to verify the condition and operability of system components affecting safe andproper control of the reactor.Page 137Texas Engineering Experiment Station NSC Specification

1. The control rods shall be visually inspected for deterioration biennially.

2. Operability tests of the control rod mechanism shall follow modification or repairs.3. The Transient Rod drive cylinder and associated air supply system shall be inspected, cleaned and lubricated semiannually.

4. The scram time shall be measured annually or whenever any work is done on the control rodsor the control rod drive system.Basis1. The visual inspection of the control rods is made to evaluate corrosion and wearcharacteristics caused by operation of the reactor.2. These tests provide verification that the control rod has full travel and that the rod drop timeis within specification.

3. Inspection and maintenance of the transient rod drive assembly reduces the probability offailure of the system due to moisture-induced corrosion of the pulse cylinder and piston rodassembly.

4. Measurement of the scram time on an annual basis is a check not only of the scram systemelectronics, but also is an indication of the capability of the control rods to perform properly.

4.3 Confinement

Applicability This specification applies to the central exhaust system.Objective The objective is to ensure the proper operation of the central exhaust system to preventuncontrolled releases of radioactive material to the environment.

Specification

1. The central exhaust system shall be channel checked prior to reactor operation orradioactive material handling.

Page I 38Texas Engineering Experiment Station NSC

2. During periods of operation, or radioactive material

handling, the central exhaust systemshall be verified operable weekly including automatic isolation on receipt of a highradiation signal. This specification is not required during periods of non-operation, e.g.,holidays, extended maintenance outages.BasisExperience accumulated over several years of operation has demonstrated that the tests of thecentral exhaust system on a weekly basis are sufficient to ensure the proper operation of thesystem and control of the release of radioactive material.

4.4 Ventilation SystemsThe Ventilation System surveillance requirements are specified in TS 4.3 above.4.5 Radiation Monitoring Systems and Effluents Applicability This specification applies to the surveillance requirements for the area radiation monitoring equipment and the Facility Air Monitoring (FAM) system and to effluents.

Objective The objective is to ensure that the radiation monitoring equipment is operating with appropriate alarm settings and to ensure that gaseous and liquid effluents are in accordance with 10 CFR 20.Specification

1. The area radiation monitoring system (ARM) and the FAM system shall be calibrated

annually, shall be channel tested weekly, and shall be channel checked prior to reactoroperation.

2. The level of 41Ar in the effluent gas shall be continuously monitored during operation ofthe reactor.3. The environmental monitoring program required by TS 3.7 shall measure the integrated radiation exposure on a quarterly basis.4. The annual discharge of 41Ar shall be calculated for each annual report.5. Before discharge, the facility liquid effluents shall be analyzed for radioactive content.Page 39Texas Engineering Experiment Station NSC BasisExperience has shown that weekly verification of area radiation and air monitoring systemoperations in conjunction with annual calibration is adequate to correct for any variation in thesystem due to a change of operating characteristics over a long time span.Monitoring and calculating the amount of gaseous and liquid effluents will allow assurance thatthey are in accordance with 10 CFR 20.4.6 Experiments Applicability This specification applies to the surveillance requirements for experiments installed in the reactorand its experimental facilities and for irradiations performed in the irradiation facilities.

Obiective The objective is to prevent the conduct of experiments or irradiations that may damage thereactor or release excessive amounts of radioactive materials as a result of failure.Specification

1. A new experiment shall not be installed in the reactor or its experimental facilities until ahazard analysis has been performed and reviewed for compliance with Section 3.6 andSection 6.5 of the Technical Specifications.

Minor modifications to a reviewed andapproved experiment may be made at the discretion of the Director, or his designee, withconcurrence from the Radiation Safety Officer, or his designee.

The Director, or hisdesignee, and the Radiation Safety Officer, or his designee, shall review the hazardsassociated with the modifications and determine that the modifications do not create asignificantly different, a new, or a greater safety risk than the original approvedexperiment, and does not require a review under 1OCFR50.59.

2. The performance of an experiment classified as an approved experiment shall not beperformed until a licensed senior operator and the Radiation Safety Officer, or hisdesignee has reviewed it for compliance with these TS.3. The reactivity worth of the experiment shall be estimated or measured, as appropriate, before reactor operation.

BasisIt has been demonstrated over a number of years of experience that experiments and irradiations reviewed by the Reactor Staff and the Reactor Safety Board as appropriate can be conducted without endangering the safety of the reactor or exceeding the limits in the technical specifications.

Page 140Texas Engineering Experiment Station NSC 4.7 ALARA Radioactive Effluents ReleasedSurveillance for the LCO 3.7 ALARA Radioactive Effluents Released is incorporated into TS4.5.4.8 Primary Coolant Conditions 4.8.1 Primary Coolant PurityApplicability This specification applies to the surveillance requirements for coolant purity.Objective The objective is ensure the water quality and radioactivity of the reactor coolant remains withindefined limits.Specification

1. A sample of the coolant shall be collected and analyzed for radioactive material contentat least weekly during periods of reactor operation and at least quarterly during extendedshutdowns.

2. Conductivity of the bulk pool water shall be measured and recorded weekly.Basis1. Weekly sampling during operation is sufficient to predict trends of radioactive materialcontent from fuel or other sources.2. A small rate of corrosion continuously occurs in any water-metal system. In order to limitthis rate, and thereby extend the longevity and integrity of the fuel cladding, a watercleanup system is required.

Experience with water quality control at many reactorfacilities has shown that maintenance within the specified limits provides acceptable control.Page 141Texas Engineering Experiment Station NSC 4.8.2 Primary Coolant Level and Leak Detection Applicability This specification applies to the surveillance requirements for primary coolant level and leakdetection.

Obiective The objective is to verify the operability of the pool level alarm and monitor for pool leakage.Specification

1. The reactor pool water level shall be recorded at least weekly.2. The pool water level alarm shall be channel tested weekly.3. The pool water level alarm shall be channel checked prior to reactor operation.

Basis1. A weekly record of pool level provides a large set of comparable data over time. Thisdata can be used to determine if changes in pool level are due to leakage.2. Experience has shown that a weekly verification of operability is sufficient to ensurereliability of the alarm.4.8.3 Primary Coolant Temperature Applicability This specification applies to the surveillance requirements for primary coolant temperature channel.Obiective The objective is to verify the operability of the primary coolant temperature channel.Specification

1. Primary coolant temperature shall be recorded every 30 minutes while the reactor isoperating, or immediately following reactor startup if the reactor is to be operated for lessthan 30 minutes.2. The primary coolant temperature channel shall be calibrated semiannually.

Page 142Texas Engineering Experiment Station NSC Basis1. Changes in primary coolant temperature occur slowly due to the large volume of thepool. 30 minute intervals are sufficient to track and predict trends in temperature.

2. Experience with semiannual calibration has shown very high reliability of thetemperature channels with need for adjustment being very rare.5 Design Features5.1 Site Description Applicability This specification applies to the NSC site location.

Objective The objective is to specify the bounds of the site.Specification The licensed area of the facility is the area inside the site boundary.

The boundary is defined bythe fence surrounding the site. This description coincides with that of the restricted area.BasisThe restricted area is described in SAR 2.2.1.1, and the site boundary is shown in Figure 2-2 inthe SAR.5.2 Reactor FuelApplicability This specification applies to the fuel elements used in the reactor core.Objective The objective is to ensure that the fuel elements are of such a design and fabricated in such amanner as to permit their use with a high degree of reliability with respect to their physical andnuclear characteristics.

Page 143Texas Engineering Experiment Station NSC Specification TRIGA LEU 3 0/20 Fuel: The individual unirradiated LEU fuel elements shall have the following characteristics:

1. Uranium content:

maximum of 30 wt% enriched to maximum 19.95% Uranium-235 withnominal enrichment of 19.75% Uranium-235,

2. Hydrogen-to-zirconium atom ratio (in the ZrHx): nominal 1.6 H atoms to 1.0 Zr atomswith a maximum H to Zr ratio of 1.65,3. Natural erbium content (homogeneously distributed):

nominal 0.90 wt%, and4. Cladding:

304 stainless steel.BasisThe fuel specification permits a maximum uranium enrichment of 19.95%. This is about 1%greater than the design value for 19.75% enrichment.

Such an increase in loading would result inan increase in power density of less than 1%. An increase in local power density of 1% reducesthe safety margin by less than 2%. (TAMU LEU Conversion SAR, December 2005)The fuel specification for a single fuel element permits a minimum erbium content of about 5.6%less than the design value of 0.90 wt%. (However, the quantity of erbium in the full core mustnot deviate from the design value by more than -3.3%). This variation for a single fuel elementwould result in an increase in fuel element power density of about 1-2%. Such a small increase inlocal power density would reduce the safety margin by less than 2%. (TAMU LEU Conversion SAR, December 2005)The maximum hydrogen-to-zirconium ratio of 1.65 could result in a maximum stress underaccident conditions in the fuel element clad about a factor of 2 greater than for a hydrogen-to-zirconium ratio of 1.60. This increase in the clad stress during an accident would not exceed therupture strength of the clad. (GA Report E-1 17-883, February 1980)Stainless steel clad has been shown through decades of operation to provide a sufficient barrieragainst fission product release.Page 144Texas Engineering Experiment Station NSC 5.3 Reactor CoreApplicability This specification applies to the configuration of fuel and in core experiments.

Objective The objective is to ensure that provisions are made to restrict the arrangement of fuel elementsand experiments to provide assurance that excessive power densities will not be produced.

Specification

1. The core shall be an arrangement of TRIGA LEU uranium-zirconium hydride fuel-moderator bundles positioned in the reactor grid plate.2. The reflector, excluding experiments and experimental facilities, shall be anycombination of graphite, water, and heavy water.3. Fuel shall not be inserted or removed from the core unless the reactor is subcritical by atleast 50 cents more than the calculated worth of the most reactive fuel assembly.

Basis1. Standard TRIGA cores have been in use for years and their characteristics are welldocumented.

LEU cores including 30/20 fuel have also been operated at General Atomicsand their successful operational characteristics are available.

General Atomics and TexasA&M have conducted a series of studies documenting the viability of using LEU fuel inTRIGA reactors.

2. The core will be assembled in the reactor grid plate that is located in a pool of light water.Lightwater in combination with graphite or heavy water reflectors can be used forneutron economy and the enhancement of experimental facility radiation requirements.

3. Manipulation of core components will be allowed only when a single manipulation cannot result in inadvertent criticality.

5.4 Control RodsApplicability This specification applies to the control rods used in the reactor core.Obiective The objective is to ensure that the control rods are of such a design as to penrnit their use with ahigh degree of reliability with respect to their physical and nuclear characteristics.

Page 145Texas Engineering Experiment Station NSC Specification

1. The shim safety control rods shall have scram capability and contain borated graphite, B4C powder, or boron and its compounds in solid form as a poison in aluminum orstainless steel cladding.

These rods shall incorporate fueled followers that have the samecharacteristics as the fuel region in which they are used.2. The regulating control rod may not have scram capability and shall be a stainless rod orcontain borated graphite, B4C powder or boron and its compounds in solid form aspoison in aluminum or stainless steel cladding.

This rod is water followed in that poolwater takes the place of the rod as it is withdrawn.

It has no physical followerattachment.

3. The transient control rod shall have scram capability and contain borated graphite orboron and its compounds in solid form as a poison in an aluminum or stainless steel clad.The transient rod shall have an adjustable upper limit to allow a variation of reactivity insertions.

This rod shall incorporate an air follower.

BasisUsing neutron absorbing borated graphite, B4C powder, or boron and its compounds, satisfies thepoison requirements for the control rods. Since the regulating rod normally is a low worth rod,using a solid stainless steel rod could satisfy its function.

These materials must be contained in asuitable clad material, such as aluminum or stainless steel, to ensure mechanical stability duringmovement and to isolate the poison from the pool water environment.

Control rods that are fuelfollowed provide additional reactivity to the core and increase the worth of the control rod. Theuse of fueled followers in the LEU fueled region has the additional advantage of reducing fluxpeaking in the water filled regions vacated by the withdrawal of the control rods. Scramcapabilities are provided for rapid insertion of the control rods, which is the primary safetyfeature of the reactor.

The transient control rod is designed for a reactor pulse. The nuclearbehavior of the air follower that is incorporated into the transient rod is similar to a void.5.5 Radiation Monitoring SystemApplicability This specification describes the functions and essential components of the area radiation monitoring (ARM) equipment and the facility air monitoring (FAM) system equipment formonitoring airborne radioactivity as described in TS 3.5.1 "Radiation Monitoring."

Obiective The objective is to describe the radiation monitoring equipment available to the operator toensure safe operation of the facility.

Page 146Texas Engineering Experiment Station NSC Specification The radiation monitoring equipment listed in Table 5 shall have the following characteristics:

Table 5: NSC Radiation Monitoring Equipment Radiation Monitoring Detector Type FunctionChannelArea Radiation Monitor Monitor radiation fields in key locations.

AlarmARaO Gamma sensitive detector and readout in the control room and readout in the(ARM) emergency support center.Fl Air Mon Monitors concentration of airborne radioactive acilty nitor (FAM) -Beta-Gamma sensitive detector particulates.

Alarm and readout in the controlParticulates (FAtvl Ch. 1, 4) room and readout in the emergency support center.Monitors concentration of radioactive gases.Facility Air Monitor (FAMC3 ) Gamma sensitive detector Alarm and readout in the control room and readoutGases (FAvIM Ch. 3, 5) in the emergency support center.An alarm signal from the stack particulate, fission product, or stack gas (xenon) facility airmonitor shall automatically isolate the central exhaust system.BasisThe radiation monitoring system is intended to provide information to operating personnel of anyimpending or existing danger from radiation so that there will be sufficient time to evacuate thefacility and take the necessary steps to prevent the spread of radioactivity to the environment.

Automatic isolation capability of the central exhaust system will mitigate the spread ofradioactivity to the environment.

The Facility Air Monitor (FAM) alarm set points are calculated during the annual calibration ofthe specific FAM channel.

Each channel has an individual calibration and alarm set point.5.6 Fuel StorageApplicability This specification applies to the storage of reactor fuel at times when it is not in the reactor core.Obiective Page I 47Texas Engineering Experiment Station NSC The objective is to ensure that fuel that is being stored will not become critical and will not reachan unsafe temperature.

Specification

1. All fuel elements and fueled devices shall be stored in a geometrical array for which thek-effective is less than 0.8 for all conditions of moderation and reflection.

2. Irradiated fuel elements and fueled devices shall be stored in an array, which will permitsufficient natural convection cooling by water or air such that the fuel element or fueleddevice temperature will not exceed design values.BasisThe limits imposed by Specifications 5.6.1 and 5.6.2 are conservative and ensure safe storage.5.7 Reactor Building and Central Exhaust SystemApplicability This specification applies to the building that houses the reactor.Objective The objective is to ensure, that provisions are made to restrict the amount of release ofradioactivity into the environment.

Specification

1. The reactor shall be housed in a facility designed to restrict leakage.

The minimum freevolume in the facility shall be 180,000 cubic feet.2. The reactor building shall be equipped with a central exhaust system designed to exhaustair or other gases from the reactor building and release them from a stack at minimum of85 feet from ground level.Emergency isolation controls for the central exhaust system shall be located in theemergency support center and the system shall be designed to shut down in the event ofan alarm on the stack particulate monitor (FAM Ch. 1) or stack gas xenon (FAM Ch.5)radiation monitoring channels.

BasisThe facility is designed such that the central exhaust system will normally maintain a negativepressure with respect to the atmosphere so that there will be no significant uncontrolled leakageto the environment.

The free air volume within the reactor building is confined when there is anemergency isolation of the central exhaust system. Controls for startup and operation of thecentral exhaust system are located in the emergency support center. Proper handling of airbornePage 148Texas Engineering Experiment Station NSC radioactive materials (in emergency situations) can be conducted from the emergency supportcenter minimizing exposure to operating personnel.

5.8 Reactor Pool Water SystemsApplicability This specification applies to the pool containing the reactor and to the cooling of the core by thepool water.Objective The objective is to ensure that coolant water shall be available to provide adequate cooling of thereactor core and adequate radiation shielding.

Specification

1. The reactor core shall be cooled by natural convective water flow.2. The pool water inlet and outlet pipe for the demineralizer,

diffuser, and skimmer systemsshall not e~xtend more than 15 feet below the top of the reactor pool when fuel is in thecore.3. Pool water inlet to the heat exchanger shall have an emergency cover within the reactorpool for manual shut off in case of pool water loss due to external pipe system failure.4. A pool level alarm with readouts in the control room and at a continuously monitored remote location shall indicate a pool level less than 3 feet below the reference operating level.Basis1. This specification is based on thermal and hydraulic calculations, which show that theTRIGA-LEU core can operate continuously in a safe manner at power levels up to 2,420kW, with natural convection flow and sufficient bulk pool cooling.2. In the event of accidental siphoning of pool water through inlet and outlet pipes of thedemineralizer,

skimmer, or diffuser

systems, the pool water level will drop to no morethan 15 feet from the top of the pool, providing 17 feet of water above the core.3. Inlet and outlet coolant lines to the pool heat exchanger terminate at the bottom of thepool. In the event of pipe failure, these lines must be manually sealed from within thereactor pool. The primary outlet pipes from the heat exchanger (inlet pipes to the pool)are equipped with flapper valves. During no-flow or reverse-flow conditions, theseflapper valves close and severely restrict the flow of water through the pipe. The primaryPage 149Texas Engineering Experiment Station NSC inlet pipe to the heat exchanger (outlet pipe from the pool) must have a cover manuallyinstalled.

The cover for this line will be stored in the reactor pool.4. This alarm is observed in the reactor control room, in the emergency support center, andat a continuously staffed remote location.

Page [50Texas Engineering Experiment Station NSC 6 Administrative Controls6.1 Organization The Nuclear Science Center is operated by the Texas A&M University System's TexasEngineering Experiment Station (TEES), with responsibility within TEES resting with theDirector or his designee.

The Director of the Nuclear Science Center is responsible to the TEESdirector, or his designee, for the administration and the proper and safe operation of the facility.

Figure 1 shows the administration chart for the Nuclear Science Center. The Reactor SafetyBoard advises the director of the NSC on all matters or policy pertaining to safety. The NSCRadiological Safety Officer provides onsite advice concerning personnel and radiological safetyand provides technical assistance and review in the area of radiation protection.

Reporting Lines-- --------------

-Communication LinesFigure 1: Organization Chart for Reactor Administration

6.1.1 Structure

1. A line management organizational structure provides for personnel who willadministrate and operate the reactor facility.

2. The Director of TEES and the Director of the NSC have line management responsibility for adhering to the terms and conditions of the Nuclear Science CenterReactor (NSC) license and technical specifications and for safeguarding the publicand facility personnel from undue radiation exposure.

The facility shall be under thedirect control of the NSC Director or a licensed senior reactor operator.

Page 151Texas Engineering Experiment Station NSC

3. Management Levels:a. Level 1: TEES Licensee (Director of TEES): Responsible for the NSC facilitylicense.b. Level 2: NSC Director:

Responsible for reactor facility operation and shall reportto Level 1.c. Level 3: Supervisory SRO (One of the following

-Associate

Director, ReactorManager, or Reactor Supervisor):

Responsible for the day-to-day operation of theNSC including shift operation and shall report to Level 2.d. Level 4: Reactor Operating Staff: Licensed reactor operators and senior reactoroperators and trainees.

These individuals shall report to Level 3.4. Reactor Safety Board (RSB):The RSB is responsible to the licensee for providing an independent review and audit ofthe safety aspects of the NSC.6.1.2 Responsibility Responsibility for the safe operation of the reactor facility shall be in accordance with the lineorganization established in Section 6.1.1. In all instances, responsibilities of one level may beassumed by designated alternates or by higher levels, conditional upon appropriate qualifications.

The reactor facility shall be under the direct control of the Supervisory SRO. The Supervisory SRO shall be responsible for ensuring that all operations are conducted in a safe manner andwithin the limits prescribed by the facility

license, procedures and requirements of the Radiation Safety Officer and the Reactor Safety Board.6.1.3 Staffing1. The minimum staffing when the reactor is not secured shall be as follows:a. At least two individuals shall be present at the facility complex and shall consistof at least a licensed senior reactor operator and either a licensed reactor operatoror operator trainee;b. During periods of reactor maintenance the two individuals who shall be present atthe facility complex may consist of a licensed senior reactor operator and amember of the maintenance staff who is able to carry out prescribed writteninstructions.

During'periods when the reactor is not secured, it shall be under thedirect control the of the senior reactor operator;

c. A licensed reactor operator or senior reactor operator shall be in the control room;Page 1 52Texas Engineering Experiment Station NSC

d. The NSC Director or his designated management alternate is readily available foremergencies or on call (the individual can be rapidly reached by phone or radioand is within 30 minutes or 15 miles of the reactor facility);

ande. At least one member of the Radiation Safety Staff shall be readily available at thefacility or on call (the individual can be rapidly reached by phone or radio and iswithin 30 minutes or 15 miles of the reactor facility),

to provide advice andtechnical assistance in the area of radiation protection.

2. A list of reactor facility personnel by name and telephone number shall be readilyavailable for use in the control room. The list shall include:a. Management personnel,

b. Radiation safety personnel, andc. Other operations personnel

3. The following designated individuals shall direct the events listed:a. The NSC Director or his designated alternate who shall be SROs shall direct anyloading or unloading of fuel or control rods within the reactor core region,b. The NSC Director or his designated alternate who shall be SROs shall direct anyloading or unloading of an in-core experiment with a reactivity worth greater than$1,c. The senior reactor operator on duty shall be present at the facility and shall directthe recovery from an unplanned or unscheduled

shutdown,

d. The senior reactor operator on duty shall be present at the facility and shall directeach reactor startup and approach to power, ande. The senior reactor operator on duty shall be present at the facility and shall directall significant reactor power changes after initial startup.

A significant reactorpower change is defined as one that would disable the automatic servo control, i.e.equal to or greater than 5% of reactor power.6.1.4 Selection and Training of Personnel The selection and training of operations personnel shall be in accordance with the following:

1. Responsibility:

The NSC Director or his designated alternate is responsible for theselection,

training, and requalification of the facility reactor operators and senior reactoroperators.

Page 153Texas Engineering Experiment Station NSC

2. Selection:

The selection of operations personnel shall be consistent with the standards related to selection in ANSI/ANS-15.4-2007

3. Training Program:

The Training Program shall be consistent with the standards related totraining in ANSI/ANS-15.4-2007.

4. Requalification Program:

The Requalification Program shall be consistent with thestandards related to requalification in ANSI/ANS-15.4-2007.

6.2 Review and Audit6.2.1 Reactor Safety Board (RSB)The Reactor Safety Board shall be comprised of at least 3 voting members knowledgeable infields which relate to Nuclear Safety. One of these members, the Director of TEES (Level 1Management),

will serve as the Chairman.

If the Chairman is unable to attend one or a numberof committee meetings he may designate a committee member as Chairman Pro-tern.

Themembers are appointed by the Director of TEES (Level 1 Management) to serve one year terms.It is expected that the members will be reappointed each year as long as they are willing to serveso that their experience and familiarity with the past history of the NSC will not be lost to thecommittee.

The Director of the NSC, TAMU Radiological Safety Officer, Head of theDepartment of Nuclear Engineering, and a senior member of the NSC Radiation Safety Staffshall be ex-officio members of the RSB.6.2.2 RSB Charter and RulesThe operations of the RSB shall be in accordance with a written charter, including provisions for:I. Meeting Frequency:

The RSB shall meet annually at intervals not to exceed 15months. (Note: The facility license requires a meeting at least once per year andas frequently as circumstances warrant consistent with effective monitoring offacility activities);

2. Quorum: A quorum is comprised of not less than one-half of the votingmembership where the operating staff does not constitute a majority;

3. Voting Rules: On matters requiring a vote, if only a quorum is present aunanimous vote of the quorum is required; otherwise a majority vote is required;

4. Subcommittees:

The Chairman may appoint subcommittees comprised ofmembers of the RSB including ex-officio members to perform certain tasks.Subcommittees or members of the RSB may be authorized to act for the board;and5. Meeting Minutes:

The Chairman will designate one individual to act as recording secretary.

It will be the responsibility of the secretary to prepare the minuteswhich will be distributed to the RSB, including the Director of TEES (Level 1Management),

within three months. The RSB will review and approve theminutes of the previous meetings.

A complete file of the meeting minutes will bemaintained by the Chairman of the RSB and by the Director of the NSC.Page 154Texas Engineering Experiment Station NSC 6.2.3 RSB Review FunctionThe review responsibilities of the Reactor Safety Board or a designated subcommittee shallinclude, but are not limited to the following:

1. Review and evaluation of determinations of whether proposed changes to equipment,

systems, tests, experiments, or procedures can be made under 10 CFR 50.59 or wouldrequire a change in technical specifications or license conditions;

2. Review of new procedures, major revisions of procedures, and proposed changes inreactor facility equipment or systems which have significant safety impact to reactoroperations;

3. Review of new experiments or classes of experiments that could affect reactivity or resultin the release of radioactivity;

4. Review of proposed changes to the technical specifications and U.S. NRC issued license;5. Review of the NSC radiation protection program;6. Review of violations of technical specifications, U.S. NRC issued license, and violations of internal procedures or instructions having safety significance;

7. Review of operating abnormalities having safety significance;

8. Review of reportable occurrences listed in Section 6.6.1 and 6.6.2 of these TS; and9. Review of audit reports.6.2.4 RSB Audit FunctionThe audit function shall include selective (but comprehensive) examination of operating records,logs, and other documents.

Discussions with cognizant personnel and observation of operations should be used also as appropriate.

In no case shall the individual immediately responsible foran area perform an audit in that area. Audits shall include but are not limited to the following:

1. Facility operations, including radiation protection, for conformance to the technical specifications, applicable license conditions, and standard operating procedures:

at leastonce per calendar year (interval between audits not to exceed 15 months);2. The results of action taken to correct those deficiencies that may occur in the reactorfacility equipment

systems, structures, or methods of operations that affect reactor safety:at least once per calendar year (interval between audits not to exceed 15 months);3. The retraining and requalification program for the operating staff: at least once everyother calendar year (interval between audits not to exceed 30 months);Page 155Texas Engineering Experiment Station NSC

4. The reactor facility emergency plan and implementing procedures:

at least once everyother calendar year (interval between audits not to exceed 30 months);

and5. The reactor facility security plan and implementing procedures:

at least once every othercalendar year (interval between audits not to exceed 30 months).Deficiencies uncovered that affect reactor safety shall immediately be reported to the Director ofTEES (Level 1 Management).

A written report of the findings of the audit shall be submitted tothe Director of TEES (Level 1 Management) and the review and audit group members within 3months after the audit has been completed.

6.2.5 Audit of ALARA ProgramThe Chairman of the RSB or his designated alternate (excluding anyone whose normal jobfunction is within the NSC) shall conduct an audit of the reactor facility ALARA programannually.

The auditor shall transmit the results of the audit to the RSB at the next scheduled meeting for its review and approval.

6.3 RadiationSafety

The Radiation Safety Officer shall be responsible for implementing the radiation safety programfor the TEES/TAMUS NSC TRIGA Research Reactor.

The requirements of the radiation safetyprogram are established in 10 CFR 20. The Program should use the guidelines of theANSI/ANS-15.11-1993; R2004, "Radiation Protection at Research Reactor Facilities."

6.4 Procedures

Written operating procedures shall be prepared,

reviewed, and approved before initiating any ofthe activities listed in this section.

The procedures shall be reviewed and approved by the NSCDirector or his designated alternate, the Reactor Safety Board, and shall be documented in atimely manner. Procedures shall be adequate to ensure the safe operation of the reactor but shallnot preclude the use of independent judgment and action should the situation require such.Operating procedures shall be used for the following items:1. Startup, operation, and shutdown of the reactor;2. Fuel loading, unloading, and movement within the reactor;3. Control rod removal or replacement;

4. Routine maintenance of the control rod, drives and reactor safety and interlock systems orother routine maintenance of major components of systems that could have an effect onreactor safety;5. Surveillance checks, calibrations, and inspections of reactor instrumentation and controls, control rod drives, area radiation

monitors, facility air monitors, the central exhaustsystem and other systems as required by the Technical Specifications; Page I 56Texas Engineering Experiment Station NSC

6. Administrative controls for operations, maintenance, and conduct of irradiations andexperiments, that could affect reactor safety or core reactivity;

7. implementation of required plans such as emergency or security plans;8. Radiation protection program to maintain exposures and releases as low as reasonably achievable (ALARA);9. Use, receipt, and transfer of by-product

material, if appropriate; and10. Surveillance procedures for shipping radioactive materials.

6.5 Experiment Review and ApprovalApproved experiments shall be carried out in accordance with established and approvedprocedures.

1. All new experiments or class of experiments shall be reviewed by the RSB as required byTS 6.2.3 and implementation approved in writing by the NSC Director or his designated alternate.

2. Substantive changes to previously approved experiments shall be made only after reviewby the RSB and implementation approved in writing by the NSC Director or hisdesignated alternate.

6.6 Required Actions6.6.1 Action to be Taken in the Event of a Safety Limit Violation In the event a safety limit is violated:

1. The reactor shall be shut down and reactor operation shall riot be resumed untilauthorized by the U.S. NRC;2. An immediate notification of the occurrence shall be made to the RSB Chairman and theNSC Director, and reports shall be-made to the U.S. NRC in accordance with Section6.7.2 of these specifications; and3. A report shall be prepared which shall include:a. Applicable circumstances leading to the violation including, when known, thecause and contributing factors,b. Effect of the violation upon reactor facility components,

systems, or structures and on the health and safety of personnel and the public,c. Corrective action to be taken to prevent recurrence.

Page I 57Texas Engineering Experiment Station NSC This report shall be submitted to the RSB for review and then submitted to the U.S. NRCwhen authorization is sought to resume operation of the reactor.6.6.2 Action to be Taken in the Event of a Reportable Occurrence Other Than A Safety LimitViolation Action to be taken in the event of a reportable occurrence other than a safety limit violation:

1. NSC staff shall return the reactor to normal operating via the approved NSC procedure orshut down conditions.

If it is necessary to shut down the reactor to correct the occurrence, operations shall not be resumed unless authorized by the NSC Director or his designated alternate;

2. The NSC Director or his designated alternate shall be notified and corrective action takenwith respect to the operations involved;

3. The NSC Director or his designated alternate shall notify the RSB Chairman who shallarrange for a review by the RSB;4. A report shall be made to the RSB which shall include an analysis of the cause of theoccurrence, efficacy of corrective action, and recommendations for measures to preventor reduce the probability of recurrence; and5. A report shall be made to the U.S. NRC in accordance with Section 6.7.2 of thesespecifications.

6.7 Reports6.7.1 Annual Operating ReportAn annual report covering the operation of the reactor facility during the previous calendar yearshall be submitted to the NRC before March 31 of each year providing the following information:

1. A narrative summary of (1) reactor operating experience (including experiments performed),

(2) changes in facility design, performance characteristics, and operating procedures related to reactor safety and occurring during the reporting period, and (3)results of surveillance tests and inspections;

2. Tabulation of the energy output (in megawatt days) of the reactor, hours reactor wascritical, and the cumulative total energy output since initial criticality;

3. The number of unscheduled shutdowns and inadvertent scrams, including, whereapplicable corrective action to preclude recurrence; Page 58Texas Engineering Experiment Station NSC

4. Discussion of the major maintenance operations performed during the period, including the effect, if any, on the safety of the operation of the reactor and the reasons for anycorrective maintenance required;

5. A brief description, including a summary of the safety evaluations of changes in thefacility or in procedures and of tests and experiments carried out pursuant to Section50.59 of 10 CFR Part 50;6. A summary of the nature and amount of radioactive effluents released or discharged tothe environs beyond the effective control of the licensee as measured at or before thepoint of such release or discharge.

The summary shall include to the extent practicable an estimate of individual radionuclides present in the effluent.

If the estimated averagerelease after dilution or diffusion is less than 25% of the concentration allowed orrecommended, a statement to this effect is sufficient:

a. Liquid Waste (summarized on a monthly basis)i. Radioactivity discharged during the reporting period.1. Total radioactivity released (in Curies),2. The effluent concentration used and the isotopic composition ifgreater than 1 x 10.7 tCi/cc for fission and activation

products,

3. Total radioactivity (in curies),

released by nuclide during thereporting period based on representative isotopic

analysis, and4. Average concentration at point of release (in ý.Ci/cc) during thereporting period.ii. Total volume (in gallons) of effluent water (including dilution) duringperiods of release.b. Airborne Waste (summarized on a monthly basis)i. Radioactivity discharged during the reporting period (in Curies) for:1. 41Ar, and2. Particulates with half-lives greater than eight days.c. Solid Wastei. The total amount of solid waste transferred (in cubic feet),ii. The total activity involved (in Curies),

andPage ] 59Texas Engineering Experiment Station NSC iii. The dates of shipment and disposition (if shipped off site).7. A summary of radiation exposures received by facility personnel and visitors, including dates and time where such exposures are greater than 25% of that allowed orrecommended; and8. A description and summary of any environmental surveys performed outside the facility.

6.7.2 Special ReportsIn addition to the requirements of applicable regulations, reports shall be made to the NRCDocument Control Desk and special telephone reports of events should be made to theOperations Center as follows:1. There shall be a report not later than the following working day by telephone andconfirmed in writing by fax or similar conveyance to the NRC Headquarters Operation Center, and followed by a written report that describes the circumstances of the event andsent within 14 days to the U.S. Nuclear Regulatory Commission, Attn: Document ControlDesk, Washington, DC 20555, of any of the following:

a. Violation of safety limit (see TS 6.6.1);b. Any release of radioactivity from the site above allowed limits; andc. Any reportable occurrences as defined in TS 1.3.2. A written report within 30 days in writing to the U.S. Nuclear Regulatory Commission, Attn: Document Control Desk, Washington, DC, 20555, of:a. Permanent changes in the facility organization involving Level 1 and Level 2; andb. Significant changes in the transient or accident analysis as described in the SafetyAnalysis Report.6.8 RecordsRecords of facility operations in the form of logs, data sheets, or other suitable forms shall beretained for the period indicated as follows:6.8.1 Records to be Retained for a Period of at Least Five Years or for the Life of the Component Involved1. Normal reactor facility operation (but not including supporting documents such aschecklists, log sheets, etc. which shall be maintained for a period of at least one year),2. Principal maintenance operations, Page 160Texas Engineering Experiment Station NSC

3. Reportable occurrences,

4. Surveillance activities required by the technical specifications,

5. Reactor facility radiation and contamination surveys where required by applicable regulations,

6. Experiments performed with the reactor,7. Fuel inventories,

receipts, and shipments,

8. Approved changes in operating procedures, and9. Records of meeting and audit reports of the RSB.6.8.2 Records to be Retained for at Least One Certification CycleRecords of retraining and requalification of certified operations personnel shall bemaintained at all times the individual is employed or until the certification is renewed.

Forthe purposes of this technical specification, a certification is an NRC issued operator license.6.8.3 Records to be Retained for the Lifetime of the Reactor Facility1. Gaseous and liquid radioactive effluents released to the environs,

2. Off-site environmental monitoring surveys required by the technical specifications,

3. Radiation exposure for all personnel monitored,

4. Drawings of the reactor facility, and5. Reviews and reports pertaining to a violation of the safety limit, the limiting safetysystem setting, or a limiting condition of operation.

Page 61Texas Engineering Experiment Station NSC Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-128Responses to the U.S. NuclearRequests for Information 1-Regulatory Commission's

-14 Dated May 6, 2015Submitted June 5, 20151 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1281. The TEES/TAMUS updated SAR, dated May 2011 (ADAMS Accession No. ML 119503 76),Section 7.2.3.4.,

"Servo Control System, 'provides general information about the servocontrol system, but does not describe specific details associated with the operation orreactivity control aspects of the servo system. NUREG-153 7, Part 1, "Guidelines forPreparing and Reviewing Applications for the Licensing of Non-Power Reactors:

Formatand Content,

" Chapter 7.3, "Reactor Control System, "provides guidance that the licenseshould analyze the operation and performance of the system, including the bases for anytechnical specifications and surveillance requirements, and provide a description of theevaluation of any accident scenarios that may be created by a malfunction of the system (e.g.,a malfunction of the servo bounded by another reactivity insertion event..)a. Provide details of the servo system operation including the normal reactivity control range, regulating rod position, interlocks, and any other significant design information, orjustify why no additional information is necessary.

b. Explain if additional technical specifications are needed for the servo system, orjustify why no changes are necessary.

NSC Response a: The servo system measures departure of indicated power on the wide rangelinear channel from a preset signal. When this departure occurs, the servo system provides ashim-in or shim-out signal to the regulating rod controller, which adjusts power. Each shim-in/shim-out signal moves the regulating rod approximately 0.03% of its range of travel. Thiscorresponds to a reactivity change of approximately

$0.0003 (three hundredths of one cent).The servo can operate within 5% power of the preset point. For example, if the servo were set tomaintain power at 90% on the 100kW range, then it would remain active as long as indicated power was within 86% -94%. Three events can create a servo fault (servo system inactive).

Itcan be manually faulted with a switch, power than change more than 5% from the preset signal,or the shim safety control rod gang can be moved using the gang control switch.NSC Response b: No additional technical specifications are needed for the servo system. Aworst case failure of the system would be an introduction of a consistent shim-out signal, whichwould withdraw the regulating rod at its normal rate of travel, with no operator response.

Theregulating rod runout was analyzed using the RELAP code in cases where the reactor's initialcondition was critical at 300W (below the point of increasing fuel temperature) and where thereactor's initial condition was critical at 1MW. Both cases were found to be bound by existingsystems and posed no risk to creating fuel damage. In the critical at 300W case, the negativepower coefficient of reactivity, driven by fuel temperature in our reactor, introduced enoughnegative reactivity to prevent the reactor from reaching even 1MW. In the critical at 1MW case,the power slowly increased until a high power level scram (< 1.25MW) actuated.

2 While the "no operator response" assumption in these cases is conservative, it is extremely unlikely.

It would require a violation of proposed TS 6.1.3 "Staffing,"

Specification 1.c. In anoverwhelmingly more likely scenario the licensed operator on duty in the control room wouldrealize a malfunction was occurring and shutdown the reactor.3 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1282. The TEES/TAMUS proposed Technical Specification (TS) 5.5, "Radiation Monitoring System, " Table 5, and TS 3.5.1, "Radiation Monitoring,

" Table 3 (ADAMS Accession No.ML 15065A 068), states, in part, information regarding the Facility Air Monitors (FAMs),Channels 1, 3, 4, and 5. However, the FAMs listed in Table 3 (channels 1, 3, and 4) do notmatch the FAMchannels listed in Table 5 (channels 1, 3, 4, and 5). NUREG-1537, Part 1,Chapter 14, Appendix 14.1, Section 3.7.], "Monitoring

Systems, "provides guidance that therequired radiation monitors should be listed in the TSs. Provide revised TSs addressing theinconsistencies in the list of FAMs in Tables 3 and 5, orjustify why no changes arenecessary.

NSC Response:

The TEES/TAMUS proposed TS 3.5.1, "Radiation Monitoring,"

Table 3 will berevised to include FAM Channel 5 and be consistent with the TEES/TAMUS proposed TS 5.5,"Radiation Monitoring System,"

Table 5.Revision:

Table 1: Radiation Monitoring Channels Required for Operation 3Radiation Monitoring Channels Function NumberReactor Bridge ARM IMonitor radiation levels withinthe reactor bayStack Particulate Monitor Monitor radiation levels in the(FAM Ch. 1) exhaust air stackStack Gas Monitor Monitor radiation levels in the(FAM Ch. 3) exhaust air stackBuilding Particulate Monitor Monitor radiation levels within(FAM Ch. 4) the reactor bayStack Xenon Monitor Monitor radiation levels in the(FAMA Ch. 5) exhaust air stack4 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1283. The TEES/TAMUS proposed Technical Specification (TS) 5.5, "Radiation Monitoring System,"

Table 5, footnote (ADAMS Accession No. ML 15065A068),

states, in part, 'fissionproduct monitor;

" but does not appear to be one of the FAM channels listed in Table 5, or TS3.5.], Table 3. Furthermore, the TEESiTAMUS updated SAR, Section 7. 7.2, "Facility AirMonitors,

" described the fission product monitor as FAM Channel 2. NUREG-153 7, Part 1,Chapter 14, Appendix 14.1, Section 3. 7.], "Monitoring

Systems,

" provides guidance that therequired radiation monitors should be listed in the TSs.a. Provide a description of the fission production

monitor, consistent with the SARdescription of the FAM channels, andb. Determine if the fission product monitor should be included in the TS 5.5, Table5, and/or TS 3.5.1, Table 3. If so, provide revised TSs, orjustify why no changesare necessary.

NSC Response a: FAM Ch. 2, also referred to as "fission product monitor,"

exists to act as aninstalled replacement that can be substituted for either FAM Ch. 1 or 4. The substitution isachieved by changing the status of valves near the FAM detectors.

Since it can replace eitherFAM Ch. 1 or 4, it will automatically shut down the air handling system just as FAM Ch. 1 will.It utilizes an identical detector and calibration procedure as FAM Ch. 1 and 4.Since it acts as an installed spare, and is procedurally required to be maintained in calibration, weoperate it as an additional, but not TS required, FAM Channel.

In this configuration its intake isapproximately 10 feet away from the intake for FAM Ch. 4 in the reactor bay. When the valvestatus is changed to substitute it for FAM Ch. 1 or 4, those channels'.

suction is rerouted throughthe FAM Ch. 2 equipment.

NSC Response b: FAM Ch. 2 should not be included in the TS 5.5, Table 5, and/or TS 3.5.1,Table 3. The Footnote to Table 3 allows for a substitute to be used under specified conditions ifone of the required channels becomes inoperable.

FAM Ch. 2 exists to act as an installed replacement that can be substituted for either FAM Ch. 1 or 4. The Footnote does not requirethat suitable substitutes be listed or specifically identified.

Rather, it specifies generalcharacteristics that a suitable substitute must have.1; Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1284. The TEES/TAMUS response to IRAI No. 33. c, by letter dated March 2, 2015 (ADAMSAccession No. ML 15065A4068),

provided information on the calculation of the setpoints forsome of the FAM channels listed in proposed TS 5.5, Table 5. However, the calculation of thesetpoint for FAM Channel No. 4 was no provided.

Additionally, a description of how thesetpoints ensure that personnel exposure and doses remain below the limits of 10 CFR Part20 was no provided.

NUREG-1537, Part 1, Chapter 14, Appendix 14.1, Section 3.7.1,"Monitoring

Systems, "provides guidance that the alarm and automatic setpoints should bespecified to ensure that personnel exposures and potential doses remain below the limits of10 CFR Part 20.a. Provide the setpoint calculation for FAM Channel 4, similar to those provided forFAM Channels 1, 3, and 5. Include a setpoint calculation for the fission productmonitor (FAM Channel 2), if added to the TSs based on the response to RAI 3above, orjustify why no additional information is necessary.

b. Provide a description of the FAM channel setpoints for channels 1, 3, 4, and 5,that indicates how the setpoints ensure that personnel exposures and dosesremain below the limits of 10 CFR Part 20. Include the fission product monitor,if the response to k4INo. 3 above adds the fission product monitor to the TSs, orjustify why no changes are necessary.

NSC Response a:Channel 4 set point calculation:

1 DAC (unknown Mixture)Convrsio Facor

• z = Set point in cpmConversion Factor1Converstion factor = = p.Ci/cc/net cpmYRTKQ-gross background activityR = flowrateT = Transit time of sample, derived from d/vd = detector diameter(inches)

(inches)v.= advance rate of the filter paper ( hr6 K- (dpm),

• ftk = J ( ft3)Q average particulate counting timemax particulate counting timez = System Efficiency NSC Response b: The FAM Channel set points are calculated using the Effluent Concentrations for Cs-137, Ar-41, and Xe-125 for channels 1, 3, & 5, respectively, and the Derived AirConcentration for an unknown mixture for channel 4, set forth by 10 CFR 20 appendix B table 2.The specified concentration limit is reduced to 33%, to conform to our system efficiency, andconverted to cpm. By using the concentration limits set forth by 1 OCFR20 appendix B table 2,we can assure that the set point in cpm will prevent personnel from exceeding the limits set forthin 10 CFR 20.7 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1285. The TEES/TAMUS proposed TS 3.5.1, "Radiation Monitoring, "Specification (ADAMSAccession No. ML 15065A 068), states, in part, "The above operations...

"which appear tobe described in the Applicability section of TS 3.5.1. NUREG-1537, Part 1, Chapter 14,Appendix 14.1, Section 1.2.2, "Format, "provides guidance that the Specification information should be provided in the specified format. Provide a revised TS 3.5.1,Specification that describes the operations intended by TS 3.5.1, orjustify why no change isnecessary.

NSC Response:

The TEES/TAMUS proposed TS 3.5.1, "Radiation Monitoring,"

Specification will be revised to meet the guidance found in NUREG-1537, Part 1, Chapter 14, Appendix 14.1,Section 1.2.2, "Format."

Revision:

Reactor operation, movement of irradiated fuel elements or fuel bundles,conduct of core or control rod work that could cause a change in reactivity of more thanone dollar, or handling of radioactive materials with the potential for airborne releaseshall not be conducted unless the radiation monitoring channels listed in Table 3 areoperable, displays and alarms are operable in the control room, and displays are operablein the Emergency Support Center.8 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1286. The TEES/TAMUS response to RAI No. 3, by letter dated November 14, 2012 (ADAMSAccession No. ML 12321A321),

provided the maximum exposure to an individual in anunrestricted area (at the fence line) that was based on the conservative assumption that theexposure was due to a total immersion in the plume generated from the immediate, groundlevel release of all fission products, from the reactor bay to the environment, that wereproduced by the maximum Hypothetical Accident (MHA). Since the actual facility responseto a significant radiological release would be to shutdown the exhaust system in order tolimit the release of the MHA airborne radioactive materialfrom the reactor bay, anadditional calculation is needed to demonstrate the conservative assumption provided by theplume model calculation.

NUREG-]53 7, Part 1, Chapter 13, Section 13.1.1, "MaximumHypothetical

Accident, "provides guidance that sensitivity analysis of the assumptions maybe useful to determine more realistic results.

Provide an estimate of the annual dose to amember of the public at the unrestricted area given that the MHA activity is confined in thereactor bay as a result of the isolation of the exhaust system (a simplified direct shinecalculation assuming no leakage could be provided as a conservative estimate),

orjustify why no additional information is necessary.

NSC Response:

By using the previously accepted immersion DDE of 6.2 mrem in 5 min, we get75 mnrem per hour in the reactor bay. The distance from the reactor bay to the closest unrestricted area is approximately 245 feet.6.2mremm *12 = 75 mrem per hourInverse square law states:I, D2Therefore, 75 mrem 2452ft12 12ft75 = 60025127560025 = 120.0013 mrem per hour = 12Annual Dose to the general public:0.0013 mrem

• 24 hr

• 365.25 days = 11 mrem per yearThe annual dose to a member of the general public at the unrestricted area give that the MHA isconfined in the reactor bay as a result of the isolation of the exhaust system can be estimated at9 11 mrem per year. It should be noted that the maximum dose rate found for the plume model was0.4 mrem per hour compared to 0.00 13 mrem per hour in this contained case.10 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1287. The TEES/TAMUS proposed TS 1.3, "Definition, "Pool Water Reference Operating Level(ADAMS Accession No. ML 15065A 068), sates, in part, "the fission product air monitor."

NUREG-153 7, Part 1, Chapter 14, Appendix 14.1, Section 1.3, "Definitions" providesguidance that the definitions applicable to a facility should be included verbatim.

Withregard to the response to RAI No. 3 above, determine if a revision of the definition of PoolWater Reference Operating Level is necessary, and provide a revision to the TS Definition ofPool Water Reference Operating Level, orjustify why no change is necessary.

NSC Response:

The TEES/TAMUS proposed TS 1.3, "Definition,"

Pool Water Reference Operating Level will be revised to meet the guidance found in NUREG-1537, Part 1, Chapter 14,Appendix 14.1, Section 1.3, "Definitions."

The reference to "the fission product air monitor"will be removed.Revision:

Pool Water Reference Operating LevelThe pool water reference operating level is 10 inches below the top of the pool wall. Thislevel is designed to prevent pool water from rising above the top of the liner.11 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1288. The TEES/TAMUS proposed TS 1.3, "Definition.,

"Reactor Console Secured (ADAMSAccession No. ML 15065A 068), states, in part, that -whenever all scrammable rods...However, the definition does no explain why it is limited to all scrammable rods and does notinclude all control rods. NUREG-1537, Part 1, Chapter 14, Appendix 14.]. Section 1.3,"Definitions" provides guidance that the definitions applicable to a facility should beincluded verbatim.

Determine if a revision to the TS definition of Reactor Console Secured isneeded to include all control rods, and provide a revised TS definition of Reactor ConsoleSecured, orjustify why no change is necessary.

NSC Response:

The TEES/TAMUS proposed TS 1.3, "Definition,"

Reactor Console Securedwill be revised to meet the guidance found in NUREG-1537, Part 1, Chapter 14, Appendix 14.1,Section 1.3, "Definitions."

The reference to "all scrammable rods" will be revised to "all controlrods."Revision:

Reactor Console SecuredThe reactor console is secured whenever all control rods have been verified to be fullyinserted and the console key has been removed from the console.12 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-1289. The TEES/TAMUS proposed TS 1.3, "Definition, "Reference Core Condition (4DAMSAccession No. ML 15065A068),

states, in part, "the reactivity worth of Xenon is negligible."

However.

negligible is not defined.

NUREG-1537, Part , Chapter 14, Appendix 14.1,Section 1.3, "Definitions

" provides guidance that the definitions applicable to a facilityshould be included verbatim.

Provide a description of how TAMUS/TEES plans toimplement the term "the reactivity worth of Xenon is negligible,

" in the definition ofReference Core Condition in operating procedures, or other guidance to the operators toensure compliance with the TSs, orjustify why no additional information is necessary.

NSC Response:

The TEES/TAMUS proposed TS 1.3, "Definition,"

Reference Core Condition will be revised to meet the guidance found in NUREG-1537, Part 1, Chapter 14, Appendix 14.1,Section 1.3, "Definitions."

The word "negligible" will be changed to "less than $0.01". Thisnumber is greater than zero in order to account for the small amounts of 135Xe always present inthe reactor fuel, and is smaller or equal to 1 cent primarily because the NSC currently has nomethod which allows for accurate determination of reactivity differences smaller than 1 cent.Revision:

Reference Core Condition The condition of the core when it is at ambient temperature (cold) and the reactivity worth of xenon is less than $0.01.13 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-12810. The TEES/TAMUS proposed TS 3.2.2, "Reactor Systems and Interlocks, "Specification (ADAMS Accession No. ML 15065A 068), states, in part, "any single safety channel orinterlock may be inoperable with the reactor is operating...

"may contain a typographical error. Consider if "with" should be changed to "when ", or if another revision is needed, orjustify why no change is necessary.

NSC Response:

The TEES/TAMUS proposed TS 3.2.2, "Reactor Systems and Interlocks,"

Specification indeed contains a typographical error. It will be revised to correct this error.Additionally, based on conversation with the U.S. NRC, "...for the purpose of maintenance, surveillance, calibration, or repair,"

will be revised to more clearly describe the intent.Revision:

However, any single safety channel or interlock may be inoperable when thereactor is operating for the purpose of performing a channel check, channel test, orchannel calibration.

14 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-12811. The TEES/TAMUS proposed TS 3.2.2, "Reactor Systems and Interlocks,

" Table 2b, SafetyChannel, Pulse Stop Electro-Mechanical Interlock (ADAMS Accession No. ML 15065A068),

states the finction is the prevent application of air to the Transient Rod unless themechanical stop is installed.

The corresponding Basis, Interlocks Required for Operation, item 5, states in part, that the interlock prevents application of air to the transient rod unlessthe cylinder isfidly inserted.

The TS 3.2.2, Pulse Stop Electro-Mechanical Interlock finctionand Basis description do not match. NUREG-153 7, Part ], Chapter 14, Appendix 14.1,Section 1.2.2, "Format, "provides guidance that the Basis information should be provided inthe specified format. Provide a revised TS 3.2.2 to correct the discrepancy between theInterlock finction as described in Table 2b and the Basis item 5, or justify why no change isnecessary.

NSC Response:

The corresponding Basis for the TEES/TAMUS proposed TS 3.2.2, "ReactorSystems and Interlocks,"

Table 2b, Safety Channel, Pulse Stop Electro-Mechanical Interlock willbe revised to meet the guidance of NUREG-1537, Part 1, Chapter 14, Appendix 14.1, Section1.2.2, "Format."

The Basis will accurately correspond to the Interlock function as described inTable 2b.Revision:

The interlock to prevent application of air to the transient rod unless themechanical pulse stop is installed prevents a reactor pulse of sufficient worth to exceedthe temperature safety limit.15 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-12812. The TEES/TAMUS proposed TS 3.3.2., "Equipment to Achieve Confinement, "Specification 4(ADAMS Accession No. ML 15065A068),

states, in part., "the fission product...facility airmonitor.

" With regard to the response to RAI No. 3 above, determine if a revision of the TS3.3.2, Specification 4 is necessary, and provide a revision to TS 3.3.2, Specification 4., orjustify why no change is necessary.

NSC Response:

The TEES/TAMUS proposed TS 3.3.2, "Equipment to Achieve Confinement,"

Specification 4 will be revised to remove the reference to "the fission product...facility airmonitor."

Revision:

The central exhaust system shall be isolated automatically by alarm levelsignals from the stack particulate, or stack gas (xenon) facility air monitor.16 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-12813. The TEES/TAMUS proposed TS 5. 7, "'Reactor Building and Central Exhaust System,Specification 3 (ADAMS Accession No. ML 15065A068),

states, in part, "the system shall bedesignated to shutdown in the event of an alarm on the stack particulate monitor (FAM Ch.1) radiation monitoring channel.

The TEES/TAMUS updated SAR, Section 7. 7.2, "Facility Air Monitors,

" indicates that FAM Channels 1, 2, and 5 automatically shutdown the facilityair handling system. NUREG-1537, Part 1, Chapter 14, Appendix 14.1, Section 3.7.1,"IMonitoring

Systems, "provides guidance that the required radiation monitors should belisted in the TSs. Provide a revised TS 5.7, Specification 3, which indicates which FAMchannels automatically shutdown the facility air handling system, orjustify why no change isnecessary.

NSC Response:

The TEES/TAMUS proposed TS 5.7, "Reactor Building and Central ExhaustSystem,"

Specification 3 will be revised to indicate which FAM channels required by TS 3.5.1,"Radiation Monitoring,"

and TS 5.5, "Radiation Monitoring System" automatically shutdownthe facility air handling system.Revision:

Emergency isolation controls for the central exhaust system shall be located inthe emergency support center and the system shall be designed to shut down in the eventof an alarm on the stack particulate monitor (FAM Ch. 1) or stack gas xenon (FAM Ch.5)radiation monitoring channels.

17 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-12814. The TEES/TAMUS proposed TS 6.1.3, Specification

3. e (ADAMS Accession No. ML15065A 068), states, in part, "equal to or great...

-which may contain a typographical error.Consider if "great" should be changed to "greater

", if another revision is needed, orjustifv, why no change is necessary.

NSC Response:

The TEES/TAMUS proposed TS 6.1.3, "Staffing,"

Specification 3.e indeedcontains a typographical error. It will be revised to correct this error.Revision:

The senior reactor operator on duty shall be present at the facility and shalldirect all significant reactor power changes after initial startup.

A significant reactorpower change is defined as one that would disable the automatic servo control, i.e. equalto or greater than 5% of reactor power.18 Texas A&M Engineering Experiment StationNuclear Science CenterLicense No. R-83Docket No. 50-128Telephone conversations subsequent to receiving these RAIs identified several desirable revisions to the TSs. These proposed revisions are described below.TS 3.1.6, "Maximum Excess Reactivity,"

Basis: It was identified that the Specification of $7.85needed a more exact Basis than currently exists, and the Oregon State University (OSU) TSidentified as an example of one done well. Following the OSU example, the following will beadded:The nominal total rod worth is $16.00 (SAR 4.5.3.2 and historic data). Subtracting the shutdownmargin ($0.50),

the nominal rod worth of the most reactive rod ($4.00),

and adding the allowedtotal reactivity worth for all experiments

($5.00) gives a result of $16.50.The specification of $7.85...TS 3.2.2, "Reactor Safety Systems and Interlocks,"

Basis: The statement, "If multiple channelshave failed simultaneously, then involvement of the U.S. NRC in recovery planning will benecessary,"

would be more appropriate for an equipment failure response procedure rather thanin the TS. It will be deleted.TS 3.2.2, "Reactor Safety Systems and Interlocks,"

Interlocks Required for Operation, Basis 1:The wording,

"...available for startup,"

is inaccurate.

It will be revised to read, "...available forproper indication."

TS 3.3.1, "Operations that Require Confinement,"

Specification 3: There is a typographical error. The word "cause" is missing between "could a." It will be revised to read, "Core orcontrol rod work that could cause a change in reactivity of more than one dollar; or"TS 3.6.1, "Reactivity Limits,"

Objective:

The objective will be revised to read, "The objective isto prevent damage to the reactor or excessive release of radioactive materials in case of failure ofan experiment."

TS 3.6.1, "Reactivity Limits,"

Basis 2: The basis will be revised to read, "The maximum worthof a single secured experiment..."

TS 3.6.1, "Reactivity Limits,"

Basis 3: The basis will be revised to read, "This limit poses arestriction on the total absolute reactivity of experiments..."

TS 5.5, "Radiation Monitoring System,"

Basis: The paragraph beginning with, "The reactorbridge Area Radiation Monitor..."

was identified as not needed and will be removed.19 TS 5.5, "Radiation Monitoring System,"

Basis: The sentence beginning with, "The following list..."

was included as a copy/paste error. It will be removed.20