ML20153A460
| ML20153A460 | |
| Person / Time | |
|---|---|
| Site: | University of Missouri-Columbia |
| Issue date: | 06/01/2020 |
| From: | Meffert B, Robertson J Univ of Missouri |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML20153A460 (7) | |
Text
(ii university of Missouri Research Reactor Center 1513 Research Park Drive Columbia, MO 65211 PHONE 573-882-4211 WEB murr.missouri.edu June 1, 2020 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001
REFERENCE:
Docket No. 50-186 University of Missouri-Columbia Research Reactor Renewed Facility Operating License No. R-103
SUBJECT:
Written communication as specified by 10 CFR § 50.4(b)(l) regarding revisions to the bases for Technical Specifications 3.4.a, 3.4.b, and 4.4.a Enclosed are revisions to the Bases of University of Missouri Research Reactor (MURR) Technical Specification (TS) 3.4, "Reactor Containment Building," and TS 4.4, "Reactor Containment Building," specifically TS 3.4.a, TS 3.4.b, and TS 4.4.a.
Enclosure I provides the basis for revising the Bases of TS 3 .4.a, TS 3.4.b, and TS 4.4.a. Enclosure 2 contains the revised TS pages with track changes. Enclosure 3 contains the revised TS pages with changes accepted and revision bars.
If there are any questions regarding this license amendment request, please contact me at MeffertB@missouri.edu or by calling (573) 882-5118. I declare under penalty of perjury that the foregoing is true and correct.
ENDORSEMENT:
Sincerely, Reviewed and Approved Reactor Manager Reactor Facility Director JACClUEUNE L MATYAS MyComlllissloft Eiqies Maltll26,2023 HowerdCouftty Conmssbl #15634308
cc: Reactor Advisory Committee Reactor Safety Subcommittee Isotope Use Subcommittee Dr. Mark McIntosh, Vice Chancellor for Research, Graduate Studies and Economic Development Mr. Geoffrey Wertz, U.S. Nuclear Regulatory Commission Mr. Craig Bassett, U.S. Nuclear Regulatory Commission
Enclosures:
- 1. Revisions to the Bases of Technical Specifications 3.4.a, 3.4.b, and 4.4.a
- 2. Revised Technical Specification Pages A-25 and A-47 (with track changes)
- 3. Revised Technical Specification Pages A-25 and A-47 (with accepted changes, revision bars)
Page 2 of 2
Enclosure l - Revisions to the Bases of Technical Specifications 3.4.a, 3.4.b, and 4.4.a Technical Specifications 3.4.a and 3.4.b The bases ofTeclmical Specifications 3.4.a and 3.4.b currently state:
"a. - b. Specifications 3.4.a and 3.4.b assure that the reactor containment building can be isolated at all times except when plant conditions are such that the probability of a release of radioactivity is negligible."
The bases of Technical Specifications 3.4.a and 3.4.b will be revised as follows:
"a. Specification 3.4.a assures that the reactor containment building can be isolated at all times to prevent or mitigate an uncontrolled release of radioactivity to the environment.
Actuation of the reactor isolation system satisfies the conditions of reactor containment integrity.
- b. Specification 3.4.b assures that reactor containment integrity shall be maintained at all times except when plant conditions are such that the probability of a release of radioactivity is negligible."
This revision provides each Specification better context from the Safety Analysis Report (SAR) while also providing clarity that when a reactor isolation is initiated that reactor containment integrity exists as discussed in Chapter 6 of the SAR.
Technical Specification 4.4.a The basis for Technical Specification 4.4.a currently states:
"a. Annual measurement of the containment building leakage rate has proven adequate to ensure that the leakage rate of the structure will remain within the design limits outlined in Specification 5.5.c. No repairs or modifications will be performed prior to the test so that the results demonstrate the historic integrity of the containment structure."
The basis for Technical Specification 4.4.a will be revised as follows:
"a. Historic containment building leakage rate data indicates that biennial measurement has proven adequate to ensure that the leakage rate of the structure will remain within the design limits outlined in Specification 5.5.c. No repairs or modifications will be perfonned prior to the test so that the results demonstrate the historic integrity of the containment structure."
This revision is required because issuance of Amendment No. 39 to Renewed Facility Operating License No. R-103 increased the surveillance requirement of measuring the containment building leakage rate from annually to biennially.
Page 1 of 1
- Revised Technical Specification Pages A-25 and A-47 (with track drnnges) UNIVERSITY OF MISSOURI RESEARCH REACTOR TECHNICAL SPECIFICATIONS Docket No. 50- 186, License No. R-103 3 .4 Reactor Containment Building - Continued
- c. When reactor containment integrity is required, the reactor containment building shall be automatically isolated if the activity in the ventilation exhaust plenum or at the reactor bridge indicates an increase of 10 times above previously established levels at the same operating condition. Exception: The containment isolation set point may temporarily be increased to avoid an inadvertent scram and isolation during controlled evolutions such as experiment transfers or minor maintenance in the reactor pool area. The pool area shall be continuously monitored, and, if necessary, a manual containment isolation actuated, until the automatic set point is reset to its normal value.
Bases:
a.-&.- Specifications 3 .4.a and 3 .4 .b assures that the reactor containment building can be isolated at all times to prevent or mitigate an uncontrolled release of radioactivity to the environment. Actuation of the reactor isolation system satisfies the conditions of reactor containment integrity.
- b. Specification 3 .4. b assures that reactor containment integrity shall be maintained at all times except when plant conditions are such that the probability of a release of radioactivity is negligible.
- c. Radiation monitors located at the reactor bridge and in the reactor contaimnent building ventilation exhaust plenum supply input signals to meters located in the reactor control room. A containment isolation will occur when radiation levels in these areas exceed a predetermined value. During operations such as the removal of experiments or equipment from the pool, the radiation level at the level of the reactor bridge or in the exhaust plenum can increase significantly for short periods.
To prevent inadvertent containment isolations, it may be necessary to raise the set point on the reactor bridge or exhaust plenum monitor. During periods in which the set point is raised to more than one decade above the normal reading, the radiation level in the area of the monitor will be continuously monitored. Thus, should the radiation level increase from unknown causes or from material which could be released to the unrestricted environment, the reactor containment building can be quickly isolated by manually actuating the isolation system.
A-25
- Revised Technical Specification Pages A-25 and A-47
(" ith track changes) UNIVERSITY OF MISSOURI RESEARCH REACTOR TECHNICAL SPECIFICATIONS Docket No. 50-186, License No. R-103 4.4 Reactor Containment Building Applicability:
This specification applies to the surveillance requirements on the containment system.
Objective:
The objective of this specification 1s to reasonably assure proper operation of the containment system.
Specification:
- a. The reactor containment building leakage rate shall be measured biennially, plus or minus four (4) months. The test shall be performed by the make-up flow, pressure decay, or reference volume techniques. No repairs or modifications shall be perfonned just prior to the test.
- b. The reactor containment building leakage rate shall be measured following any modification or repair that could affect the leak-tightness of the building.
- c. The containment actuation (reactor isolation) system, including each of its radiation monitors, shall be tested for operability at monthly intervals.
- d. When required by Specification 3.4.b, containment integrity shall be verified to exist within a shift.
Bases:
- a. HistoricAnnual measurement of the contaimnent building leakage rate data indicates that biennial measurement has proven adequate to ensure that the leakage rate of the structure will remain within the design limits outlined in Specification 5.5.c. No repairs or modifications will be performed prior to the test so that the results demonstrate the historic integrity of the containment structure.
- b. Measurement of the containment building leakage rate following any modification or repair that could affect the leak-tightness of the building ensures that the leakage rate of the structure will remain within the design limits outlined in Specification 5.5.c.
- c. The reliability of the containment actuation (reactor isolation) system has proven that monthly verification of its proper operation is sufficient to assure operability.
- d. Specification 4.4.d assures that containment integrity is verified to exist to limit the leakage of contained potentially radioactive air in the event of any reactor accident to ensure exposures are maintained below the limits of 10 CFR 20.
A-47
- Revised Technical Specification Pages A-25 and A-47 (with accepted changes, revision bars) UNIVERSITY OF MISSOURI RESEARCH REACTOR TECHNICAL SPECIFICATIONS Docket No. 50- 186, License No. R-103 3.4 Reactor Containment Building - Continued
- c. When reactor containment integrity is required, the reactor containment building shall be automatically isolated if the activity in the ventilation exhaust plenum or at the reactor bridge indicates an increase of 10 times above previously established levels at the same operating condition. Exception: The containment isolation set point may temporarily be increased to avoid an inadve11ent scram and isolation during controlled evolutions such as experiment transfers or minor maintenance in the reactor pool area. The pool area shall be continuously monitored, and, if necessary, a manual containment isolation actuated, until the automatic set point is reset to its normal value.
Bases:
- a. Specification 3.4.a assures that the reactor containment building can be isolated at all times to prevent or mitigate an uncontrolled release of radioactivity to the environment. Actuation of the reactor isolation system satisfies the conditions of reactor containment integrity.
- b. Specification 3.4.b assures that reactor containment integrity shall be maintained at all times except when plant conditions are such that the probability of a release of radioactivity is negligible.
- c. Radiation monitors located at the reactor bridge and in the reactor containment building ventilation exhaust plenum supply input signals to meters located in the reactor control room. A containment isolation will occur when radiation levels in these areas exceed a predetermined value. During operations such as the removal of experiments or equipment from the pool, the radiation level at the level of the reactor bridge or in the exhaust plenum can increase significantly for short periods.
To prevent inadvertent containment isolations, it may be necessary to raise the set point on the reactor bridge or exhaust plenum monitor. During periods in which the set point is raised to more than one decade above the nonnal reading, the radiation level in the area of the monitor will be continuously monitored. Thus, should the radiation level increase from unknown causes or from material which could be released to the unrestricted environment, the reactor containment building can be quickly isolated by manually actuating the isolation system.
A-25
- Revised Technical Specification Pages A-25 and A-47 (with accepted changes, revision bars) UNIVERSITY OF MISSOURI RESEARCH REACTOR TECHNICAL SPECIFJCATIONS Docket No. 50-186, License No. R-103 4.4 Reactor Containment Building Applicability:
This specification applies to the surveillance requirements on the containment system.
Objective:
The objective of this specification 1s to reasonably assure proper operation of the containment system.
Speci fi cation:
- a. The reactor containment building leakage rate shall be measured biennially, plus or minus four (4) months. The test shall be perfonned by the make-up flow, pressure decay, or reference volume techniques. No repairs or modifications shall be performed just prior to the test.
- b. The reactor containment building leakage rate shall be measured following any modification or repair that could affect the leak-tightness of the building.
- c. The containment actuation (reactor isolation) system, including each of its radiation monitors, shall be tested for operability at monthly intervals.
- d. When required by Specification 3.4.b, containment integrity shall be verified to exist within a shift.
Bases:
- a. Historic containment building leakage rate data indicates that biennial measurement has proven adequate to ensure that the leakage rate of the structure will remain within the design limits outlined in Specification 5.5.c. No repairs or modifications will be performed prior to the test so that the results demonstrate the historic integrity of the containment structure.
- b. Measurement of the containment building leakage rate following any modification or repair that could affect the leak-tightness of the building ensures that the leakage rate of the structure will remain within the design limits outlined in Specification 5.5.c.
- c. The reliability of the containment actuation (reactor isolation) system has proven that monthly verification of its proper operation is sufficient to assure operability.
- d. Specification 4.4.d assures that containment integrity is verified to exist to limit the leakage of contained potentially radioactive air in the event of any reactor accident to ensure exposures are maintained below the limits of 10 CFR 20.
A-47