IR 05000454/1985051

Insp Repts 50-454/85-51 & 50-455/85-37 on 851125-27.No Violations or Deviations Noted.Major Areas Inspected:Gaseous & Liquid Radioactive Programs,Including Effluent Releases & Effluent Control Instrumentation

ML20136H987
Person / Time
Site:	Byron
Issue date:	01/07/1986
From:	Hueter L, Schumacher M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20136H985	List: IR 05000454/1985051 ML20136H978
References
50-454-85-51, 50-455-85-37, NUDOCS 8601130129
Download: ML20136H987 (5)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION III

Reports No. 50-454/85051(DRSS); 50-455/85037(ORSS)

Docket Nos. 50-454; 50-455 Licenses No. NPF-37; CPPR-131 Licensee: Commonwealth Edison Company Post-Office Box 767 Chicago, IL' 60690

~ Facility Name: Byron Station, Units 1 and'2 Inspection At: Byron Station, Byron, IL Inspection Conducted: ' November 25-27, 1985 5 . llAd Inspector: L. J. Huete I'7-Eb Date Approved By:

9 M. C. Schumacher, Chief

Radiological Effluents Date and Chemistry Section

. Inspection Summary

. Inspection on November 25-27, 1985 (Reports No. 50-454/85051(DRSS);

50-455/85037(DRSS))

Areas Inspected: Routine unannounced inspection of gaseous and liquid-radioactive programs including:. effluent releases, records and reports of effluents; procedures for controlling releases; and effluent control instrumentation. The inspection involved 27 inspector-hours on site by one NRC inspecto Results: No violations or deviations were identifie .$ oS $ 54 PDR

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,, . ' Gaseous Effluents The inspect!or reviewed selected records of radioactive gaseous effluent

-_ sampling and analysis for-1985,~ to date, and the semiannual effluent report for the first_ half of 198 The pathways sampled and analyses performed appear to comply with the requirements of Technical Specification Table 4.1 Unit 11and Unit 2 have separate vent stacks which are continuously monitored / sample Some gaseous effluents, such as gas decay tank effluent,' release to a common plenum and may exhaust through either stack or.be divided between the two stacks. Other sources of gaseous radwaste Lsuch as the effluent from the radwaste volume reduction facility are directed to Unit 2 vent stac Unit 1 achieved initial criticality on February 2,1985 and full power during the summer of 1985. Noble gas releases are quantified daily based on gas decay tank releases, containment venting or-purges and any activity identified on the vent monitor not attributable to the other

. sources stated above. Gas grab samples'are also collected daily from the vent stacks and a gamma analysis performed for noble gas identificatio :Usually the concentrations are below the detection limit. Xenon-133 is the'only nuclide identified in these samples and the highest concentration has been about 1E-7 pCi/m Noble gas releases were somewhat elevated in September and October 191:5, (approaching.300 Ci'each month) due to valve packing leaks in containn en Tightening the packing had helped.some during operation. Repairs of the leaks were initiated during the outage which began on October 25th. hable

, gas releases remained less than one percent of applicable 10 CFR 50 Appendix I limit The background subtraction feature of the vent stack noble gas monitort are not being used due to a problem when negative numbers are generatec

.from low net count rates. Rectification of this software problem is being pursued with the instrument vendor. In the interim, noble gas releases-quantified from the vent stack monitors are somewhat conservativ Vent stack iodine and particulate samples are collected daily (due to dust loading from continued construction work on Unit 2), but quantifiec weekly. Tritium releases in gaseous effluents are quantified daily from samples collected from the vent stack using silica gel. Reluases of the sum of iodine, particulate (greater than eight day, half life), and tritium in gaseous effluents have remained less than one percent of applicable 10 CFR Appendix I limit Potential problems were identified by the inspector in review of Byron Chemistry procedure BCP 400-T47, Revision 3, " Gaseous Radioactive Waste Release Form" relating to over conservatism in certain calculations and possible nonconservatism in others. The simplified method of calculating

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DETAILS

' Persons Contacted

• A. Britton,-QA. inspector

• J. Langan, Compliance Staff

• R. Querio,. Byron Station Manager

• D. St. Clair, Operations Engineer, Radwaste J.' Van. Laere, Rad-Chem Supervisor J. Ventimiglia, Technical Staff

.* Walters, QA Engineer

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. R.' Ward, Services Superintendent, Byron

• K. Weaver,-Station Health Physicist

. J. Hinds, Jr.', NRC Senior Resident Inspector

, *J.' Malloy, NRC Resident Inspector The inspector also~ contacted other licensee personne * Denotes those present at the exit meetin . Action on Previous Inspection Findings f

(Closed) Violation (454/85038-01(DRSS)): Failure to follow liquid radwaste release procedures. The inspector reviewed the licensee's response and verified that Byron Chemistry Procedure BCP 400-T50, " Liquid Radwaste' Release Form", has been revised to require independent

' verification of circulating water blowdown flow by the Shift Control Room Engineer and Radwaste Foreman prior to a release occurrin Also, a-placard is now posted in the control room indicating when a release is in

' progres Also, annunciator response procedure BAR 1-17-A13 for the circulating water pump trip alarm has been temporarily revised (permanent revision pending) to consider its effect on liquid radwaste releases that

'may be in progress. As an additional precaution, a modification has been initiated (scheduled to.be implemented prior to the end of the first refueling outage) to: provide automatic isolation of a liquid release when circulating water blowdown flow falls below the minimum required flow rate. The corrective actions taken appear appropriat (0 pen) Violation (454/85038-02(DRSS)): Failure to take timely action when a Technical Specification LCO release limit was exceeded. The inspector reviewed the licensee's initial response which asserted that the violation was predicated on a misunderstanding by the NRC and, furthermore, that an analysis not previously available for NRC review, demonstrated that the release was adequately diluted before release to

-.the river. .On these bases, the licensee requested reconsideration by NRC of the validity of this violatio In consideration of this request the NRC responded by clarifying the basis for the violation and requesting submission of the referenced analysis in order to continue its revie _

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a release.from a Waste Gas Decay Tank (WGDT) based on noble gas instantaneous release rate limit .is very conservativ The activity concentrations in the WGDT, the Unit.1 vent stack, and the Unit 2 vent stack are summed and considered to be present in.the total release. The method can produce a-safety factor exceeding 10,000 when both vent stacks are operating and there is little activity concentration except the WGDT. This calculation has, on occasion, approached the limit for release of a WGDT even with relatively low activity concentration in a WGDT. The procedure could unnecessarily prohibit releases on the basis of radioactivity limits at

times when release to' control hydrogen and oxygen concentrations may be indicate By. contrast, the method of calculating maximum allowable WGDT-release flow rate assumes the WGDT is the only source of noble gas released from the-plant during the release period; the result is divided by a factor of two for an apparent safety facto The same method is used for calculating the maximum noble gas release rates for containment purges and vent This method may not be conservative if the sole source assumption is incorrect._ The inspector's review of release records, identified no occasions when the plant release rate had been exceeded to date. The potential procedural problems were discussed at the exit. (0 pen Item 454/85051-01; 455/85037-01).

Dur.ing inspector review of WGDT release forms and records, it was-noted that the continuously operating noble gas monitor (on the WGDT release line down stream of the flow controller / isolation valve) indicates concentrations on the order of 1 to 2 E-2 pCi/cc during occasional non release periods. The reasons for the anomaly is unknown, nor is enough

. recorded data available to currently evaluate the cause. Potential causes could be (1) residual activity from the previous release irculating in the line downstream of the isolation valve (there are no ;.rovisions for flushing the line in the current procedure); (2) activity from the vent line (vent for liquid tanks) into which the. release line eventually connects; or-(3) possible leak from WGDT(s) and through the isolation valve. This anomaly was discussed at the exit. (0 pen Iten 454/85051-02; 455/85037-02).

No violations were identifie . Liquid Effluents The inspector reviewed selected records and procedures associated with controlled liquid releases for 1985 to date and the semi annual effluent

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report for the first half of 1985._ The pathways sampled and analysis performed appear to comply with the requirements of Technical Specification Table 4.11- The activity (excluding tritium) in liquid batch releases in July and August reached 3.8Ci and 4.8Ci, respectively, before problems in the liquid radwaste treatment' systems were remedied in early September and both

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_ evaporators.and dimineralizers were made available to treat liquids prior to release. During the peak release period, whole body and organ doses were well below the levels requiring operability and use of the liquid radwaste treatment system by Technical Specification 3.11. Liquid releases were again somewhat elevated for a short period following the outage which began on October 25th, due to a reactor coolant crud burst (principally Co-58) in the primary syste flo violations were identifie . Instrument Calibrations The inspector reviewed calibration records for the vent stack normal range noble gas effluent monitors, the low and high range WGDT monitors, the liquid radwaste effluent monitor and the station blowdown effluent monito No violations'or deviations were identifie . Open Items Open items are matters which have been discussed with the licensee, which will be reviewed further by the inspector, and which involve some action on the part of the NRC or licensee or both. Open items disclosed during the inspection are discussed in Paragraph . Exit Interview The inspector summarized the scope and findings of the inspection with licensee representatives (Section 1) at the conclusion of the inspection on November 27, 1985. The inspector discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspector during the inspection. The licensee did not identify such documents or processes as proprietary. In response to certain items discussed by the inspector, the licensee: Committed to review and revise as necessary Byron Chemistry Procedure BCP 400-T47 Revision 3, to preclude potential problems associated with over conservation in certain conservation and possible non conservation in other calculations regarding gaseous effluent release dose limits and release flow rates from special planned releases such as WGDT and containment purges and vent (Section 3) Committed to evaluate cause of occasional readings significantly above background observed on the WGDT effluent line monitor between tank releases and evaluate feasibility of eliminating the proble (Section 3)

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