0CAN099901, Application for Amends to Licenses DPR-51 & NF-6,changing TS by Revising Curie Limits for Radioactive Gas Storage Tanks

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Application for Amends to Licenses DPR-51 & NF-6,changing TS by Revising Curie Limits for Radioactive Gas Storage Tanks
ML20212F578
Person / Time
Site: Arkansas Nuclear  Entergy icon.png
Issue date: 09/17/1999
From: Titus F
ENTERGY OPERATIONS, INC.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20212F583 List:
References
0CAN099901, NUDOCS 9909280282
Download: ML20212F578 (8)
v • d • e


Text

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t 4.,-- Entergy operitions, Inc.

"h P.O Box 31995 Jackson, MS 39286-1995 Tel 601368 5390 Fred W.Titus Vice President Engineenna September 17,1999 OCAN099901 U. S. Nuclear Regulatory Commission Document Control Desk Mail StaJon OPI-17 Washingtcn, DC 20555

Subject:

Arkansas Nuclear One - Unit I and Unit 2 Docket No. 50-313 and 50-368 License Nos. DPR-51 and NPF-6 Proposed Technical Specification Change Revising The Curie Limits for Radioactive Gas Storage Tanks Gentlemen:

Attached for your review and approval are proposed changes to the Arkansas Nuclear One --

Unit 1 (ANO-1) and Unit 2 (ANO-2) Technical Specifications (TS). The proposed change affects ANO-1 and ANO-2 Limiting Conditions for Operation and associated bases applicable to the maximum allowable curie content contained within radioactive gas storage tanks. The revised limits are currently being administratively controlled a'. ANO and are conservative with respect to the ANO-1 and ANO-2 TS limits. The proposed TS change is necessary to ensure the ANO-1 and ANO-2 TSs adequately bound the safety analysis.

ANO-1 and ANO 2 TSs currently require the maximum quantity of radioactivity contained within the gas storage tanks of the ANO-1 and ANO-2 Gaseous Radwaste (GRW) System to be limited to 300,000 curies (Ci) based on a Xe-133 equivalency. In accordance with >

NUREG-0800, this limit would ensure that, upon an uncontrolled release of the tank's contents over a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> period, the resulting totd whole body exposure to a member of the public at the nearest exclusion area boundary will not exceed 0.5 rem. Given the aforementioned scenario, ANO has determined that the 300,000 Ci limit will result in an l exposure equal to a small fraction of 10 CFR 100 limits, but will be in excess of 0.5 rem.

Therefore, calculations have been performed to determine the Xe-133 equivalent curie content that would result in an exposur.: of 0.5 rem or less, consistent with the limits of NUREG-0800, Branch Technical Position ETSB 11-5, Postulated Radioactive Releases Due to a Waste Gas System Leak or Failure. As a result, new limits have been established and 0\

approved for the ANO-1 ar3d ANO-2 GRW storage tanks. The new limits are 78,782 Ci and 82,400 Ci for ANO-1 and ANO-2 respectively. Therefore, Entergy Oper .tions, Inc. is proposing to revise the ANO-1 and ANO-2 TSs to reflect these new limits.

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U. S. NRC September 17,1999 OCAN099901 Page 2 This proposed change has been evaluated in accordance with 10 CFR 50.91(a)(1) using criteria in 10 CFR 50.92(c) and it has been determined that this change involves no significant hazards considerations. The bases for these determinations are included in the attached submittal.

The proposed changes are necessary to maintain the required level of control et eming the quantity of radioactivity stored within the GRW tanks. The current limits established for ANO-1 and ANO-2 are more restrictive relative to existing TS requirements and are presently under administrative control.

Entergy Operations requests prompt NRC review and approval of the proposed changes.

Since the proposed setpoint is currently being administratively controlled in the plant operating procedures, no implementation period is required.

Very truly yours, FWT/dbb Attachment To the best of my knowledge and belief, the statements contained in this submittal are true.

1 SUBSCRIBED AND SWORN TO before me, a Notary Public in and for 14 nd5 l County and the State of Mississippi, this l ~lDday of Se.ekm b<< ,1999.

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U. S. NRC September 17,1999 '

OCAN099901 Page 3 cc: Mr. Ellis W. Merschoff Regional Administrator U. S. Nuclear Regulatory Commission

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Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 NRC Senior Resident Inspector Arkansas Nuclear One P.O. Box 310 London, AR 72847 Mr. Nick Hilton NRR Project Manager Region IV/ANO-1 U. S. Nuclear R.egulatory Commission ,

NRR Mail Stop 04-D-3 One White Flint North 11555 Rockville Pike l Rockville, MD 20852 Mr. Crais Nolan NRR Project Manager Region IV/ANO-2 U. S. Nuclear Regulatory Commission NRR Mail Stop 04-D-3 One White Flint North 11555 Rockville Pike Rockville, MD 20852 Mr. David D. Snellings Director, Division of Radiation Centrol and Emergency Management Arkansas Department of Health 4815 West Markham Street Little Rock, AR 72205

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, , ATTACHMENT 1 10

, OCAN099901 PROPOSED TECHNICAL SPECIFICATION AND BESPECTIVE SAFETY ANALYSES IN THE MATTER OF AMENDIN_Q 1,1 CENSE NO. DPR-51 AND NPF-6 ENTERGY OPERATIONS. INC.

ARKANSAS NUCLEAR ONE. UNIT ONE AND UNIT TWO DOCKET NO. 50-313 AND 50-368 l

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' Attachment I to 0CAN099901 v Page1of4 DESCRIPTION OF PROPOSED CHANGES 4 l

The proposed changes to the' Arkansas Nuclear One, Unit 1 (ANO-1) and Unit 2 (ANO-2)

Technical SpecificationsL(TS) decrease the maximum allowable quantity of radioactivity in a Gaseous Radwaste (GRW) System gas storage tank. The following changes are proposed:

  • For ANO-1, the limit established for the maximum quantity of radioactivity in a GRW storage tank in Specification 3.25.2 and its associated bases is revised from 300,000 Ci to -

s a new value of 78,782 Ci.

  • For ANO-2, the limit established for the maximum quantity of radioactivity in a GRW.

storage tank in Specification 3/4.11.2 is revised from 300,000 Ci to a value of 82,400 Ci.

The following sections will provide the bases for the aforementioned changes. Because the proposed changes affect both units at Arkansas Nuclear One (ANO), any future reference to "ANO" will imply both ANO-1 and ANO-2, unless specifically stated otherwise.

BACKGROUND The ANO-1 GRW System consists, in part, of 4 gas storage tanks, each designed to receive, ,

and hold for decay, radioactive gaseous effluents from various plant systems, including the  ;

reactor coolant system (RCS). The ANO-2 GRW System is similarly designed, but contains I just 3 gas storage tanks. Exhausted effluents from these tanks could, if of sufficient radiological content, have an adverse effect on the health and safety of the public. Therefore, )

in order to limit any such adverse effect on the public, restrictions are placed on the quantity j of radioactivity that a tank is permitted to contain at any given time. This philosophy was adopted through the issuance of NUREG-0800, Branch Technical Position Il-5, " Postulated Radioactive Releases Due to a Waste Gas System Leak or Failure." Although the original design basis for ANO-1 or' ANO-2 do not require conformance with NUREG-0800, the respective TSs have acted to provide the assurance oflimiting adverse effects that may result during a loss of gas storage tank contents.

During a study of component classifications within the GRW System, ANO determined that the existing 300,000 Ci limit for the gas storage tanks for ANO-1 and ANO-2 may not adequately ensure that exposure to a member of the public at the nearest exclusion area boundary during an inadvertent gas storage tank release over a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> time period would be limited to 0.5 rem. Using the guidance provided in Branch Technical Position ETSB 11-5 of NUREG-0800, new ca'culations were subsequently performed. As a result of these calculations, new limits were established for ANO-1 and ANO-2 gas storage tanks and

. administrative controls were established to ensure compliance with the new limits. A discussion of the new limits is included in the following section.

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l Attachment I to l ,

OCAN099901 l . Pag 3 2 0f 4 l

l DISCUSSION OF CHANGE A total exposure for a person at the exclusion area boundary was calculated assuming a failure of a single gas storage tank containing the maximum calculated activity per NUREG 0800 guidelines. The result indicated that the subsequent exposure (0.853 rem) would be limited to a small fraction of the 25 rem required by 10 CFR 100. Branch Technical Position ETSB 11-5, however, requires such subsequent exposures to be limited to 0.5 rem. In order to target the lower value of 0.5 rem, new limits were calculated and established for the gas storage tanks at ANO-1 and ANO-2. Regulatory Guide 1.109 dose conversion factors were used in the calculations to determine the Xe-133 equivalent curie content that w uld limit offsite exposure to 0.5 rem. For ANO-1, the new limit was determined to be 78,762 Ci in any single gas storage tank, and for ANO-2, the limit was determined to be 82,400 Ci in any single gas storage tank. The new limits may require the use of more than one, but less than two gas storage tanks to contain the gaseous activities associated with an accident involving 1% failed fuel. Therefore the new limits allow the GRW System of both units to maintain the capability to perform their intended storage function with volume to spare. If the quantity of radioactivity is maintained within these new limits, the resultant exposure at the exclusion area boundary, as described previously, would be limited to 0.5 rem.

A search of available historical activity data associated with the gas storage tanks indicated that previous tank contents remained well below the proposed new limits. Procedures and processes were enhanced to alert Chemistry and Operations personnel to initiate corrective actions should a gas storage tank approach the aforementioned limits. In addition, the

, programs and methods used to evaluate the "ctivity content of a gas storage tank were verified to be accurate and assured to include a conversion to Xe-133 equivalency, for which the new limits are based upon.

In summary, the new gas storage tank activity limits presently established at ANO-1 and ANO-2 adequately ensure that a member of the public at the exclusion area boundary will not receive more than 0.5 rem of exposure should the entire contents of a gas storage tank be inadvertently released over a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> period of time. Based on the above background and discussions, ANO requests the aforementioned changes to ensure the ANO-1 and ANO-2 TSs adequately bound the safety analyses.

DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION Entergy Operations, Inc. is proposing that tl e Arkansas Nuclear One, Unit 1 (ANO-1) and Unit 2 (ANO-2) Operating Licenses be amended to revbe the maximum activity limit allowed to be contained within a Gaseous Radwaste (GRW) System gas storage tank. The new limits act to ensure the exposure to a member of the public is limited to 0.5 rem as recommended in NUREG-0800 Branch Technical Position 11-5, " Postulated Radioactive Releases Due to a Waste Gas System Leak or Failure", in the event that a gas storage tank's content is inadvertently released. The proposed changes are necessary to ensure the ANO-1 and ANO-2 Technical Specifications (TS) adequately bound the safety analyses.

Attachment 1 to 0CAN099901

. Page 3 of 4.

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- An evaluation of the proposed change has been performed in accordance with I

'10CFR50.91(a)(1) regarding no significant hazards considerations using the standards in I 10CFR50.92(c); A dhcussion of these standards as they relate to this amendment request

- follows:

Criterion 1 - - Does Not Involve a Significant Increase in the Probability or Consequences of an Accident Previously Evaluated.

l The proposed change to. lower the current technical specification (TS) gas storage tank activity limits does not require new hardware or physical equipment modifications to the plant design. By lowering the setpoint, the resultant exposure at the exclusion area boundary upon an inadvertent release of a gas storage tank's content will be- l timited to 0.5 rem. Therefore the consequences of such an uncontrolled release of activity are effectively reduced. Additionally, no new accident is introduced by the proposed reduction in activity limits associated with the gas storage tanks.

l Therefore, reducing the gas storage tank limits from 300,000 Curies (Ci) to 78,782 Ci and 82,400 Ci (ANO-1 and ANO-2, respectively) does not involve a significant increase in the probability or consequences of any accident previously evaluated.

Criterion 2 - Does Not Create the Possibility of a New or Different Kind of Accident from any Previously Evaluated.

4 The proposed change affects the consequences of an event associated with the loss of gas storage tank radioactive contents on either ANO-1 or ANO-2. Since this event has been previously evaluated, no new or different accident can be associated with the proposed change. Decreasing the present TS activity limits results in an cxposure at the exclusion area boundary to be limited to 0.5 rem in the event of an inadvertent release of a gas storage tank's content.

Therefore, this change does aqi create the possibility.of a new or different kind of  :

accident from any previously evaluated.

Criterion 3 - Does Not Involve a Significant Reduction in the Margin of Safety.

The proposed change conservatively lowers the existing TS GRW System gas storage tank activity limits from 300,000 Ci to 78.782 Ci and 82,400 Ci (ANO-1 and ANO-2 respectively). In doing so, the resultant exposure to a member of the public at the I exclusion area boundary during an inadvertent release of gas storage tank contents i

, over a two-hour period is reduced to 0.5 rem or less. The proposed change, therefore, retains the margin of safety for both ANO-1 and ANO-2.

Therefore, this change does nat involve a significant reduction in the margin of safety.

Attachment I to .

OCAN099901

, Page 4 of 4 1

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Iherefore, based on the' reasoning presented above end the previous discussion of the i amendment request, Entergy Operations, Inc. has deternuned that the requested change does not involve a significant hazards consideration.

ENVIRONMENTAL IMPACT EVALUATION 10 CFR 51.22(c) provides criteria for and identification of licensing and regulatory actions eligible for categorical exclusion from performing an environmental assessment. A proposed amendment to an operating license for a facility requires no environmental assessment if operation of the facility in accordance with the proposed amendment would not: (1) involve a significant hazards consideration, (2) result in a significant change in the types or significant increate in the amounts of any effluents that may be released off-site, or (3) result in a significant increase in individual or cumulative occupational radiation exposure. Entergy Operations, Inc. has reviewed this license amendment and has determined that it meets the  ;

eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to I 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be

_ prepared in connection with the issuance of the proposed license amendment. The bases for I this determination is as follows:

1 The proposed license amendment does not involve a significant hazards consideration as described previously in the evaluation.

2. As discussed in the significant hazards evaluation, this change does not result in a significant change or significant increase in the radiological doses for any Design ,

Based Accident. The proposed license amendment does not result in a significant j change in the types or a significant increase in the amounts of any effluents that may be j released off-site.

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3. The proposed license amendment does not result in a significant increase to the individual or cumulative occupational radiation exposure because this does not modify the method of operation of systems and components necessary to prevent a radioactive release.

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