ML19319A955
| ML19319A955 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 12/22/1976 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19319A954 | List: |
| References | |
| NUDOCS 7912300238 | |
| Download: ML19319A955 (1) | |
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%J, SAFETY EVALUATION REPORT ON RADWASTE SYSTEM MODIFICATIONS OCONEE NUCLEAR STATION, UNIT NOS. 1, 2 AND 3 Docket Nos. 50-269/270/287 r
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SUMMARY
DESCRIPTION During startup of Oconee, Unit No. 2, in early 1973, the licensee determined that the capacity of the radwaste systems, as des-cribed in the FSAR was not adequate to process all radwaste inputs from the combined operation of Unit Nos. 1, 2 and 3 during normal operation including anticipated operational occurrences.
To alleviate the inadequate capacity, the licensee designed and installed additional. interim radwaste system equipment which was
'to be later replaced with a permanent radwaste system. The design and installation of the interim radwaste system equip-ment was completed prior to fuel loading of Unit No. 3.
In the " Waste Management Facility Safety Analysis Report", dated June 23, 1975, which was submitted for our review in accordance with 10 CFR 50.59, the licensee describes the interim radwaste facility and proposes that the radwaste facility installed for interim use be approved for permanent use.
'2.0 SYSTEM DESCRIPTION AND EVALUATION
' The interim radwaste equipment and controls for the liquid and
. aseous waste _ management systems are located in the newly erected-g Waste Management Facility Building which is located between the U
Unit 3 Reactor Building and the Component Cooling Water Intake
-Structure.
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. The liquid radwaste system modification consists of the installation of (1) a 15 gpm radwaste evaporator package complete with an integral control panel, (2) an evaporator condensate mixed-bed demineralizer, and (3) two additional liquid radwaste holdup tanks having a total capacity of 34,000 gallons.
The liquid radwaste system was also modified to segregate laundry waste from other miscellaneous liquid radwaste drains. The original liquid radwaste system had a 5 gpm radwaste evaporator and six (6) liquid radwaste collection and holdup tanks with a total capacity of 48,000 gallons.
In addition, Oconee has a 5 gpm boric acid evaporator in the boron recycle system. 'Ihe distillate from the boric acid evaporator is routed to the condensate tanks in the liquid radwaste system and the evaporator bottoms are routed to the solid radwaste system 'or solidification. At a meeting at the Oconee Station, on May 18, 1976, the licensee stated that an attempt will be made to cleanup the boric acid evaporator and recycle concentrated boric acid for reuse within the plants. At the preant time, the boric acid evaporator is used interchangeably with liquid radwaste evaporator.
The modified liquid radwaste system will provide a combined storage capacity of 82,000 gallons. Based on the parameters for liquid rad-waste input volume given in NUREG-0017, we have calculated the-average expected liquid radwaste input from Units 1, 2, and 3 to be
.11,800 gallons per day including 1.5 gpm/ reactor shim bleed but excluding the Turbine Building floor drains. The licensee estimated i
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, a. total liquid radwaste input of 10,200 gpd from Unit Nos.1, 2 and 3: based on the. actual operating data. The two radwaste evaporators (one 5 gpm and one:15 gpm) and one 5 gpm boric acid evaporator provide a combined effective process capacity of 12 gpm
. or 17,280 gpd compared to the nominal capacity of 25 gpm or 36,000 gpd.
Evaporator throughput has been approximately 64% of the rated capacity and evaporator availability has been 75%,
leading to the lower effective capacity.
Based on t'.'is e'perience, the capacity of the modified liquid radwaste system is adequate to 1
the anticipated demands of the plant during normal operation of meet
' Unit Nos. 1, 2 and-3' including anticipated operational occurrences.
The gaseous ;radwaste system modification includes three (3) 1070 cubic feet carbon steel tanks to provide additional waste gas storage capacity (two tanks to the Units 1 and 2, and one tank to Unit 3). The original gaseous radwaste system had two 1070 cubic foot carbon steel tanks for each gaseous radwaste system (Oconee
-Unit Nos. I and 2 share a common gaseous radwaste system and a
-single system is provided for Unit 3). The modification -increases the holdup capacity of each gaseous radwaste system to approximately 53 days from 30 days, based on a design pressure of 100 psig with a nominal operating pressure of 85 psig.
The solid radwaste system modification consists of installation of-a skid mounted liquid waste solidification package, 'which employs i;=
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, urea formaldehyde as a solidifying agent. 'D1is package is installed in the existing Auxiliary Building.
We have reviewed the licensee's quality assurance provisions for the modified radwaste systems and the quality group classifications used for system components, and find a portion of the piping and valves in the liquid waste solidification package and liquid waste evaporator do not meet the criteria set forth in Branch Technical Position, ETSB 11-1.
The licensees, in a letter dated December 16, 1975 in response to our request for additional inf;rmation, has identified and proposed to replace the piping and valves which do not meet Branch Technical Position ETSB 11-1.
We find the. proposed replacement of these items in the modified radwaste system to be acceptable.
We have reviewed the provisions incorporated in the modified radwaste system design to control and monitor the release of radioactive materials in effluents. The modified liquid radwaste system design does.not' add any new release points since discharges are made through the existing discharge line. All additional liquid and gaseous radwaste tanks are contained within the Waste Management Facility Building, and the equipment drains and liquid radwaste tank over-flows are collected in the building _ sump and pumped to the radwaste receiving - tanks. Each additional gaseous waste decay tank is provided with a relief valve which discharges to the existing Unit 3 y
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5 vent stack. The liquid radwaste tanks are vented-to the building.
.The building exhaust is discharged to the: atmosphere without treatment through the building roof vent and monitored for only noble gases. The n'necadensable gases from the waste evaporator are vented to the Unit Nc. I vent stack.
We will require that the Waste Management Facility Building vent exhaust be continuously sampled and monitored for iodine and parti-culates'in addition to the noble gas monitoring system installed i
at the present time. The building vent exhaust is a potentially significant path for release of radioactive materials due to equipment and system leakages during normal reactor operations, including anticipated operational occurrences, and therefore, should have these provisions as recommended in Regulatory Guide 1.21, in order to meet the requirements of General Design Criterion 64.
The licensee has stated, in a letter dated June 30,1976, in response to our request for additional information that they will install radiation monitoring equipment which will be capable of detecting iodines and particulates in the building ventilation exhaust.
We have reviewed the modified solid radwaste system design and find that the system does not have provisions to verify the absence of free liquidoin drummed solid waste, in accordance with Branch Technical Position, ETSB 11-3, Complete solidification of. wastes should.be. assured by the implementation of a process control program 4
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... or by methods to detect free liquids within container contents
. prior.to shipment as described in fa) or (b) below.
l (a) Process Control Program Solidification agents and potential waste constituents 1.
should be tested and a set of process parameters estab-lished which provide boundary conditions within which reasonable assurance can be given that solidification l
will be complete.
The plant operator should provide assurance that the 2.
process is run within the parameters established under 1 above. Appropriate records should be maintained for individual batches showing conformance with the estab-lished parameters.
(b)
Free Liquid Detection Each container filled with solidified wet wastes should be checked by suitable methods to verify the absence of free liquids. Visual inspection of the upper surface of the waste in the container is not alone sufficient to ensure that free water is not present in the container. Provisions to be used to verify the absence of free liquids should consider actual solidification procedures which may create a thin layer of solidification agent on top without affecting the lower; portion of the container. -
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.a EVALUATION FINDINGS 3.0 l
s The scope of our review included an evaluation of effluent re eas itd based on -the. modified radwaste processes, review of the asso of the descriptive informa-i
. piping and instrument diagrams, rev ew Safety Analysis
' tion in the licensee's Waste Management Facility The Report, and review of the licensee's plant operational data.
has been conformance of the
. bases for acceptance in our review bases.
licensee's design modifications, design criteria, and design for the modified radwaste systems to the Commission's Regu ff technical and to applicable Regulatory Guides, as well as the sta positions and industry standards.
design modi-Based on the foregoing evaluation, we conclude that the fications of the Oconee radwaste systems are acceptable a d in the system provided that the design deficiencies identifie The capability of the modified radwaste foregoing evaluation are n..
Part 50 systens to meet the requirements of-Appendix I to 10 CFR l tion Report.
will be evaluated in a supplement to the Safety Eva ua l
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