ML11195A051
| ML11195A051 | |
| Person / Time | |
|---|---|
| Site: | Texas A&M University |
| Issue date: | 07/11/2011 |
| From: | Juzaitis R Texas A&M Univ |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 2008-001, AGN-201M | |
| Download: ML11195A051 (12) | |
Text
DWIGHT'LOOK COLLEGE OF ENGINEERING Department of Nuclear Engineering
-U TXS &
July 11, 2011 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Docket No.50-059
SUBJECT:
Supplemental Information for the Texas A&M University AGN-20 1 M reactor License Application To supplement the license application for the Texas A&M University AGN-201M reactor, modification authorization 2008-1 dated January 23, 2008 is being submitted. This document outlines the reactor console instrumentation and electronics upgrade performed by the facility.
Also included is the Statement of Intent for decommissioning costs.
If you have any questions, please do not hesitate to contact me at: (979) 845-4161, or e-mail at rjuzaitisgtamu.edu.
I declare under penalty of perjury that the foregoing is true and correct. Executed on July 11, 2011.
129 Zachry Engineering Center 3133 TAMU College Station, TX 77843-3133 Tel. 979.845.4161 Fax. 979.845.6443 http://nuclear.tamu.edu
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DWIGHT LOOK COLLEGE OF ENGINEERING Department of Nuclear Engineering
-U TXS &
June 16, 2011 U. S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
TAMU AGN-201M Teaching Reactor, (TAC. NO. ME1 588)
Texas A&M University Financial Assurance STATEMENT OF INTENT As Department Head of the Nuclear Engineering Department at Texas A&M University, I exercise authority and responsibility to request from the Dean of the College of Engineering funds for decommissioning activities associated with operations authorized by the U. S. Nuclear Regulatory Commission TAMU AGN-201 M (TAC NO.
ME1588). This authority is established by the President's Delegation of Authority for Contract Administration (see attached, Section 9.1 Permits, Licenses, Declaration, Applications Filed with Regulatory Agencies). Within this authority, I intend to request that funds be made available in the amount of $ 97,850 to decommission the AGN Reactor located in the Zachry Building (Bldg. 518) on the campus of Texas A&M University, College Station, Texas 77845 (estimated costs of decommissioning are $97,850).
I intend to request and obtain these funds sufficiently in advance of decommissioning to prevent delay of required activities.
Ray ond J. Ju ii 5P
.D Dp*tment He Sallie & Don Davis '61 Pkf ssor of Engineering Department of Nuclear Engineering G. KemllTe nnett, Ph.D.,7P.E.
Vice C cellor and Dean of Engineering Di Wor, Texas Engineering Experiment Station Harold J. Haynes Dean's Chair Professor Phillip Ray Associate Vice President for Finance Vice President for Finance & Cfo 129 Zachry Engineering Center 3133 TAMU College Station, TX 77843-3133 Tel. 979.845.4161 Fax. 979.845.6443 http://nuclear.tamu.edu Isa T
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Modification Authorization #2008-1 1-22-08 Page 1 of 10 Texas A&M University Department of Nuclear Engineering MODIFICATION AUTHORIZATION
Title:
- 1. AGN Staf
- 2.
Reactor S AGN Reactor Console Instrumentation and Electronics Upgrade Review:
I ] *Dtj fpeart ent Head Dat afety Board Review:
b The Reactor Safety Board has reviewed the hazards associated with this modification IAW 10 CFR 50.59 and has determined that it does not:
- 1. Result in more than a minimal increase in the frequency of occurrence of an accident previously evaluated in the final safety analysis report (as updated);
- 2.
Result in more than a minimal increase in the likelihood of occurrence of a malfunction of a structure, system, or component (SSC) important to safety previously evaluated in the final safety analysis report (as updated);
- 3.
Result in more than a minimal increase in the consequences of an accident previously evaluated in the final safety analysis report (as updated);
- 4.
Result in more than a minimal increase in the consequences of a malfunction of an SSC important to safety previously evaluated in the final safety analysis report (as updated);
- 5.
Create a possibility for an accident of a different type than any previously evaluated in the final safety analysis report (as updated);
- 6.
Create a possibility for a malfunction of an SSC important to safety with a different result than any previously evaluated in the final safety analysis report (as updated);
- 7.
Result in a design basis limit for a fission product barrier as described in the FSAR (as updated) being exceeded or altered; or
- 8. Result in a departure from a method of evaluation described in the FSAR (as updated) used in establishing the design bases or in the safety analyses.
Approval Confirmed:
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RSB Chairman 123 5 / E
- 3.
Restrictions:
- 4.
RSB Subcommittee Review (if necessary):
Name (Print): _____
Signature:
Date:
Name (Print):
Signature:
Date:
- 5.
Final Modification Authorization:
Head (Print):
Signature:
Date:
Modification Authorization #2008-1 1-22-08 Page 2 of 10 Safety Evaluation of the AGN Reactor Console Instrumentation and Electronics Upgrade Introduction The Texas A&M University AGN console instrumentation and electronics has been used since 1957. The analog console was very old and replacement parts were no longer available. The upgraded digital console will enhance the human-machine interface. The console enables the operator or students to view digital displays, store data, and retrieve this data in digital form. Considering the educational function of AGN reactor, digital data acquisition during operation or experiments is highly desirable. Since commercial nuclear plants, existing and forthcoming, have adopted advanced features such as digital I&C, we feel training reactors must also adopt these to avoid obsolescence.
This review is not theoretical but based on tests of the as-built console.
Description In accordance with Reg. Guide 1.70, 7.5.1 Safety-Related Display Instrumentation, the SAR should "include a description of the instrumentation systems (including control rod position indicating systems) that provides information to enable the operator to perform required safety functions."
The upgraded console is designed to have the same or better function compared to the original console. The instrumentations used have high functional reliability in harsh environments. Interlock and scram logics are same as described in FSAR Figure 7.2.1 -1 and 7.2.1-2. The upgraded equipment in the console is as follows. The detailed equipment specifications are listed in Appendix A.
- P.A.D.(Preamp/Amp/Disc)
- Log ratemeter GM Detector
" Encoder Picoammeter Alarm control
- Power supply
- Nim Bin As shown in the following figure, the logic is the same as in the old console except a computer used as digital recorder and monitor. The scram circuit is designed to trip the reactor immediately when the computer fails. The signals from some channels will bypass the computer and actuate the scram directly so that the safety redundancy is maintained.
Modification Authorization #2008-1 1-22-08 Page 3 of 10 FIGURE 7.2.1-2 A.G.N. LOGIC DIAGRAM Safety Evaluation In accordance with 10 CFR 50 Appendix A. General Design Criteria 13, Instrumentation and control, "Instrumentation shall be provided to monitor variables and systems over their anticipated ranges for normal operation, for anticipated operational occurrences, and for accident conditions." The following analysis and evaluation adequately demonstrate that the updated console instrumentation provides the same functions as described in FSAR and the same information necessary for the operator to perform required safety functions.
The scram circuitry and electronic controls are the same as used at the Nuclear Science Center where we have decades of operating experience. The function and operability of scram and interlocks will be confirmed through the daily channel testing and calibration.
The new instruments are an update and improvement over the replaced instruments.
These instruments are more reliable and sufficient means are available to indicate problems with the instruments so that this modification will not present a safety issue.
Modification Authorization #2008-1 1-22-08 Page 4 of 10 While certainly the components of the electronics themselves have changed, we have preserved the console functionality as described in the Technical Specifications. The relevant Technical Specifications that pertain to these console modifications are:
T/S 2.1.a. The reactor power level shall not exceed 100 watts.
Discussion: Neither the detectors nor their position relative to the core have changed. We replaced the counting train for Channel #1 and Channel #2 with off-the-shelf NIMbin modules. During initial critical testing we will calibrate the detectors against flux foil measurements (at a fraction of full power) to establish the power levels and LSSS for the reactor.
T/S 2.2.a. The safety channels shall initiate a reactor scram at the following limiting safety system settings:
Channel Nuclear Safety #2 Nuclear Safety #3 Condition High Power High Power LSSS
<10 Watts
<10 Watts Discussion: The detectors for Channel #2 and Channel #3 and their positions relative to the reactor are unchanged. The counting trains are off-the-shelf NIMbin modules and will be calibrated against flux foil measurements at low power.
T/S 3.2.b The average reactivity addition rate for each control or safety rod shall not exceed 0.065% Ak/k per second.
Discussion: Based on current rod worth data, this worth limits the control rods movement to 17.8 seconds or greater times for full insertion. We have lowered the operating voltage to the drive motors and the insertion times for all rods have increased from 22 to 29 seconds to 31 to 38 seconds, becoming more conservative. The out-of-core measurements for rod movement are:
Rod Safety Rod 1 Safety Rod 2 Coarse rod:
Fine rod:
Previous insertion time 23.37 seconds 22.56 seconds 27.97seconds 28.86 seconds After console modification 33 seconds 31 seconds 32 seconds 38 seconds T/S 3.2.c. The safety rods and coarse control rod shall be interlocked such that:
- 1. Reactor startup cannot commence unless both safety rods and coarse control rod are fully withdrawn from the core.
- 2. Only one safety rod can be inserted at a time.
- 3. The coarse control rod cannot be inserted unless both safety rods are fully inserted.
Modification Authorization #2008-1 1-22-08 Page 5 of 10 Discussion: The logic controlling the drive motors is such that requirements 1, 2, and 3 are satisfied T/S 3.2.d. Nuclear safety channel instrumentation shall be operable in accordance with Table 3.1 whenever the reactor control or safety rods are not at their fully withdrawn position.
Table 3.1 Safety Channel Set Point Function Nuclear Safety #1 Low count rate
>10 cps scram below 10 cps Nuclear Safety #2 High Power
<10 W scram at power > 10 W Low Power
> 1.0 x 10-12 amps scram at source levels < 1.0 x 10-12 amps Reactor Period
>5 seconds scram at period < 5 seconds Nuclear Safety #3 Linear Power High Power
<10 W scram at power > 10 W Low Power
> 5% full scale Scram at source levels < 5% of full scale Discussion: All of these scrams are part of the safety circuitry and have been fully tested with two exceptions:
First, calibrations, of course, will have to be done to assure that the power readings are correct.
Second, the power displays are autoscaling so there cannot be a low level ( <5% full scale) trip. We have not included this scram to avoid having a nonfunctional scram.
T/S 3.2.e. The shield water level interlock shall be set to prevent reactor startup and scram the reactor if the shield water level falls 9.5 inches below the highest point on the reactor shield tank manhole opening.
Discussion: The float switch position has not been changed and the electronics initiates a scram, as before.
T/S 3.2.f The shield water temperature interlock shall be set to prevent reactor startup and scram the reactor if the shield water temperature falls below 15' C.
Discussion: The temperature sensor is unchanged and the electronics initiates a scram as before.
T/S 3.2.g. The seismic displacement interlock shall be installed in such a manner to prevent reactor startup and scram the reactor during a seismic displacement.
Discussion: The seismic switch has not been altered. The safety circuitry initiates a scram on signal from the seismic indication.
Modification Authorization #2008-1 1-22-08 Page 6 of 10 T/S 3.2.h. A loss of electric power shall cause the reactor to scram.
Discussion: Loss of power de-energies the magnets and releases the rods, as before.
The failure of the computer controlling the scram circuit would cause the immediate actuation of scram (fail-safe function). If an equipment malfunction were to occur, such as failure of a nuclear instrument, the reactor would scram on the interlock relay or the scram system which is bounded as described in Chapter 13.1.9 Mishandling or Malfunction of Equipment. The failure of the proper scram operation would cause a power and temperature rise. The core thermal fuse would separate and insert a large amount of negative reactivity which is bounded by the maximum hypothetical accident (2% reactivity insertion) as described in Chapter 13.1.1.
No FSAR and Tech. Spec. modification has been made with the exception of two instrument displays (not functionality). Subsequent console appearance and model name have been replaced in FSAR Chapter 7 as attached in Appendix B. No safety evaluation for the FSAR changes is needed.
Conclusion The safety evaluation of console instrumentation and electronics upgrade has been reviewed in accordance with 10 CFR 50.59. The modification does not increase the likelihood, frequency or magnitude of the consequences of accidents or malfunctions currently analyzed by the SAR. The modification does not result in a reduction of any safety margins described in the SAR.
Modification Authorization #2008-1 1-22-08 Page 7 of 10 Appendix A. Upgraded equipment list Equipment Manufacture and model type P.A.D(Preamp/Amp/Disc)
CANBERRA Model 814A Log ratemeter ORTEC 449/449-2 Encoder NSB-10 Picoammeter KEITHLEY 486 Alarm control ORTEC 461 Power supply ORTEC 478 Nim Bin ORTEC 4001 Power supply Sola SDN Power supply Sola SFL
Modification Authorization #2008-1 1-22-08 Page 8 of 10 Appendix B FSAR changes A.G.N. LOGIC DIAGRAM Figure 7.2.1-2 NUCLEAR INSTRUMENTATION SYSTEM
Modification Authorization #2008-1 1-22-08 Page 9 of 10 U WAR POWEER Pan Alarm Test Neutron Source IN OUT 90 PanAlarm Reset O 0 Consoe Power Rod Magnets Safety Rod #1 Safety Rod #2 Coarse Rod Scram Rod Scram Rod Scram Rod Figure 7.6-2 CHANNEL DISPLAY AND ROD POSITION INDICATORS
Modification Authorization #2008-1 1-22-08 Page 10 of 10 Figure 7.6-3 INSTRUMENT PANEL