IR 05000245/1987007

Insp Rept 50-245/87-07 on 870223-27.No Violations Noted. Major Areas Inspected:Licensee Water Chemistry Control Program,Including Mgt Controls,Plant Water Chemistry Sys, Sampling/Measurement & Implementation of Program

ML20207T261
Person / Time
Site:	Millstone
Issue date:	03/17/1987
From:	Bicehouse H, Pasciak W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20207T249	List: IR 05000245/1987007 ML20207T248
References
50-245-87-07, 50-245-87-7, NUDOCS 8703230364
Download: ML20207T261 (10)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Report N /87-07 Docket No. 50-245 License No. DPR-21 Category C

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Licensee: Northeast Nuclear Energy Company P.O. Box 270 Hartford, Connecticut 06141-0270 Facility Name: Millstone Unit 1 Inspection At: Waterford, Connecticut Inspection Conducted: February 23-27, 1987 Inspectors: h b. b H. Bidehouse, Radiation Special'.st 3!/4!S7 date Approved by: soac W. Pasciak, Chief, Effluents Radiation 3 7k7

/ dAe Protection Section Inspection Summary: Inspection on February 23-27, 1987 (Report No. 245/87-07)

Areas Inspected: Routine, unannounced review of the licensee's water chemistry control program including management controls, plant water chemistry systems, sampling / measurement and implementation of the progra Results: Within the Areas reviewed, no violations were noted. Control of general corrosion, protection of fuel integrity and pressure boundaries and control of general radiation field buildup appeared to be adequat PDR ADOCK 05000245 G pop

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DETAILS 1.0 Persons Contacted 1.1 Licensee Personnel

• J. P. Stetz, Unit 1 Superintendent M. J. Bigiarelli, Unit 1 Engineering G. J.~ Closius, Quality Assurance (QA)/ Quality Control (QC) Supervisor R. Doherty, Unit 1 ALARA Coordinator

• J. P. Kangley, Rad. Services Supervisor R. Langer, Engineering Specialist, Nuclear Materials and Chemistr J. G. Law, Maintenance Engineer J. Leason, ISI Coordinator, Unit-1 Engineering

• F. C. Libby, Supervisor, Operations QA C. P. Wargo, Maintenance Engineer

• J. J. Waters, Chemistry Supervisor

• D. Wilkins, Unit 1 Chemistry Supervisor Other licensee personnel were also contacted or interviewe .2 NRC Personnel J. Grant, Resident Inspector

• T. Rebelowski, Senior Resident Inspector

• Attended the exit interview on February 27, 198 .0 Scope The licensee's Unit-1 water chemistry control program was reviewed rela-tive to Technical Specifications, the Updated Final Safety Analysis Report (UFSAR), NRC Regulatory Guidance and industry-consensus standards. The purpose of the review was to assess the licensee's program to control corrosion and out-of-core radiation field buildup, ensure long-term inte-grity of the reactor coolant pressure boundary and minimize fuel leakage

! caused by corrosion-induced failure .0 Previously Identified Item (Closed) 25-00-13 TI - Trial Use Of Water Chemistry Inspector Modules This inspection completed a series of inspections reviewing the Unit 1 water chemistry control program which involved the trial use of two ins-pection procedure This item is close . .

4.0 Management Controls The licensee's Unit _1 water chemistry control program was reviewed to determine if an effective, documented program for controlling the quality of the primary coolant water had been developed. Unit 1 Technical Specifi-cations gcVerning organization, procedures and limiting conditions for operation were used in the revie In addition, commitments in the UFSAR and the licensee's Quality Assurance Plan (QAP) and guidance provided by the Electric Power Research Institute (EPRI) Boiling Water Reactor Owner's Group (BWROG) Water Chemistry Guidelines Committee, (EPRI Report NP 3589-SR-LD) were also use .1 Management Policies The licensee's management policies regarding the Unit I water chemis-try control program were reviewed to determine if a management commit-ment to, and support for, an effective water chemistry control pro-gram had been provided. The BWROG Water Chemistry Guidelines Committee recommends that corporate management establish policies and '

procedures and provide the resources necessary to support and enforce those policie A Nuclear Engineering and Operations (NED) Policy Statement (i.e. NE0 Policy No. 7, " Plant Water Chemistry Program," Revision.1, March 10, 1982) provided a clear corporate commitment to an effective water chemistry control program. The policy statement called for chemistry control ranges, routine surveillance / trending, standardized analy-tical test methods, in plant instrumentation and data analysis and management programs to identify potential material / service conditions incompatibilities and to develop / implement controls to minimize corrosion / erosion phenomen .2 Corporate Chemistry The roles of the corporate chemistry organization in providing tech-nical support for the Unit I chemistry control program was briefly reviewed. Although past attention to Unit I wasn't evident, a grow-ing corporate chemistry involvement was noted as evidenced by the cobalt reduction program, revie~w of Unit 1 trending reports and planning for the upcoming hydrogen water chemistry test, pipe decon-tamination and passivation with the General Electric Zinc Injection Process (GE ZIP). Two persons on the Nuclear Material and Chemistry corporate staff were heavily involved in the planning and preparation for the noted activitie .3 Chemistry Department The organization of the station's Chemistry Department relative to Unit I chemistry operations appeared to be clearly defined. Within the Chemistry Department, the Unit 1 Chemistry Supervisor reported to the Chemistry Supervisor and had responsibility for the Unit 1

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water chemistry control program. Technicians (reporting to the Unit 1 Chemistry Supervisor) had responsibilities as analysts, instrument technicians and system operators and implemented the Unit I sampling and analysis program. The inspector noted that Unit 1 and Unit 2 shared a common. laboratory while a separate laboratory was provided for Unit Unit 1 chemistry staffing was reviewed relative to chemistry tech-nician routine duties (including operational analytical / sampling responsibilities). No backlogs of samples or analyses were note However, routine utilization of contracted chemistry technicians and overtime appeared to be responsible, inpart, for this lack of backlo Laboratory analytical capabilities were reviewed relative to the BWROG Water Chemistry Committee's guidelines and typical Region I utility capabilities. State-of-the-art analytical capabilities were noted allowing part per billion (ppb) measurem-nts to be routinely mad Chemistry technicians were interviewed to deternrine their understand-ing of the sampling and analytical methods used in Unit 1. The tech-nicians appeared fully knowledgeable of the licensee's method Technicians were also interviewed concerning routine operation of plant water chemistry systems and appeared to' be fully aware of the system's operations. The inspector noted that the licensee's chemis-try technician training program was being reviewed for Institute for Nuclear Power Operations (INPO) accreditation but had not received it at the time of the inspectio .4 Procedures Unit 1 procedures were reviewed to determine if instructions were provided prescribing the nature and frequency of sampling and analy-sis, administrative control limits for common contaminants, in-line instrumentation calibration and maintenance, operation of Unit I water chemistry control systems and reporting / trending various chemi-cal parameters. Nine Chemistry Procedures (CP), Four Surveillance Procedures (SP), three operating Procedures (0P) and a Maintenance Procedure (MP) were reviewed and discussed with the licensee's re-presentatives. Although basic instructions for meeting Technical Specification surveillance requirements and providing sampling fre-quencies and contaminant limits were found, the procedures failed to provide actions to be taken should contaminant limits be exceede At the exit interview on February 27, 1987, the licensee indicated that specific actions to be taken when contaminant levels exceeding administrative limits were found would be included in subsequent revisions to appropriate procedure Routine intercomparisons of in-line conductivity cells and laboratory reference cells were required by the licensee's procedures with an agreement acceptance criterion of 10%.

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Maintenance procedures governing lapping and grinding activities on hard-faced valve seats were reviewed to determine if the licensee had initiated control / cleanup procedures.to minimize the ingress of cobalt-alloy debri.s. Although routine cleanliness instructions were provided, specific instructions for retaining debris with dams and removal by vacuuming were not provided. The licensee indicated that revisions to valve maintenance procedures would be made to upgrade-debris retention / removal instruction The licensee's procedures for monitoring the growth of out-of-core radiation fields were reviewed. Following the decontamination in 1984, the licensee's ALARA group instituted a systematic radiation survey procedure for monitoring radiation field butidup on recircula-tion piping to monitor recontamination of that pip Following an INPO Audit finding, the licensee initiated an extensive upgrade program for procedures and administrative controls governing

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the onsite solvent control program (under Millstone Administrative Policy 5.08). The actions undertaken were ongoing at the time of the inspectio .5 Self-Identification / Correction of Deficiencies The licensee's program to identify and correct chemical control deficiencies was reviewed to determine if a program to identify, in-vestigate, document, report, track, close and trend discrepancies in the water chemistry control program had been developed. Data from the Unit I sampling and analysis program were routinely entered in a computer program which provided graphical presentations of trend Those trends were reviewed by Unit 1 management and distributed to corporate chemistry specialists when requested. The inspector noted that the data was not entered into a central computer program. As a result, Nuclear Materials and Chemistry staff specialists (i.e. cor-porate) were unable to directly access the data to produce their own trending plots. The licensee indicated that a centralized computer program allowing data access by both Unit 1 and corporate specialists was being develope Review of the application of the QAP to the Unit I water chemistry control program indicated that the licensee's various QA organiza-tions did not routinely review the program (except in the area of Technical Specification surveillance implementation).

5.0 Unit 1 Water Chemistry Systems 5.1 Plant Description Millstone unit 1 is a 2011 MWt, (690 W,), General Electric BWR-3 which began commercial operation in December 1970. The unit has 580

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fuel bundles, 145 control rods, moto'r-driven feed pumps and an isola-

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-tion condenser. . Seawater drawn-from Long Island Sound is used as circulating water in.the condensers. Condensate treatment is'accomp-

.11shed with 6 (160 cubic feet each) deep-bed domineralizers.(contain-ing 95 cubic: feet anion and 65 cubic feet cation resins). The Reactor Water Clean-up (RWCU) system utilizes 3 (160 cubic feet each).

deep-bed domineralizers rated at Sh. %_ full steam flow but normally

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operated at 3%. Fuel failures and chemical transients resulting.fro sea water intrusions were noted in the 1970's. The condenser tubes are copper-nickel alloy tubes. At the January 1986 startup, approxi -

mately 7.3% of "A" hotwell tubes, 10 % of "B" hotwell tubes, 6.5 % of

"C" hotwell tubes.and 9.5 % of "D".hotwell tubes were plugge Equalizer lines are employed between the "A". and "C" and "B" and "D" hotwells. Condenser leaks are common place event '

During operation, control rod drive (CRD) cooling water is taken from polished condensate and during shutdown, one deep-bed domineralizer is used to provide " polished" water for the CR0 cooling water. A line to recirculate feedwater (FW) prior to startup is provided and-normal startup procedures use that method to reduce corrosion pro-ducts in the FW prior to introduction into reactor vesse Feedwater drains are returned to the hotwell Radiation field buildup patterns for the plant were_ considered

" generic" in _th'e EPRI study. Fuel failures noted in the 1970's were believed.to be the result of pellet-cladding interactions and possibly hydriding. No fuel failures have been recorded since 197 The licensee has replaced 2/3 of the fuel elements with barrier fuel and will complete the replacement during the next' refueling outag .2 Water Systems Primary and auxiliary waterisystems ("as built") were reviewed rela-tive to descriptions and drawings provided or referenced in the UFSAR. The Condensate System was reviewed for familiarization with major components and to identify flow paths for the ingress of con-taminants into the reactor F In-line instrumentation, (e.g. conductivity cells) and sampling points were reviewed for represer.titiveness and early detection of condenser in leakage, escape of resin fines and air intrusions / seal failures. The site-wide reverse osmosis unit (" demineralized water")

was reviewed and noted to be a potential source of organic contamin-ants which required monitoring. The RWCU system was also reviewe Within the scope of this review, no problems or concerns were note The licensee had a generally conservative design for water treatment systems reflecting 1960's design standards for BWR-3 units with sea water as circulating condenser cooling wate r --

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5.3 Operation Operating schemes used for the Condensate Demineralizer and RWCU systems and for radioactive liquid waste water recycle were reviewe Calculations of remaining detonization capacity of resins were re-  !

viewed. The licensee calculates remaining capacity daily. Deep-bed '

resins are ultrasonically cleaned but are not regenerated. The lic-ensee transfers condensate demineralizer resins to the liquid rad-waste resin vessels and uses the resins there. The following table summarizes the licensee's criteria for demineralizer resin replace-ment:

System Criteria Condensate Demineralizer 30 lbs. minimum capacity based on daily calculation RWCU differential pressure or silica breakout Radwaste Treatment conductivity in effluent >0.06 microstemen per cm (uS/cm)

Fuel Pool Cleanup conductivity increase; silica breakout; chloride ion increase The licensee tests replacement resins inhouse to assure ton exchange capacity prior to the resins' introduction into the system Recycle of treated radioactive waste water to the Condensate Storage Tank is contingent on meeting the following criteria and chemistry approval:

• Conductivity < 1 pS/cm;

• Chloride < 60 ppb;

• Total Organic Carbon < 1 ppm; and

• acceptable total radioactivit However, the licensee hadn't provided criteria for purgable organic carbon, turbidity and silica. The licensee had developed an operat-ing scheme for radioactive waste water recycle generally responsive to concerns raised in NRC Information Notices Nos. 82-32 and 83-49 and INPO guidanc .4 Radiation Field Buildup The primary long-term source of radiation fields in BWRs is cobalt-60. The presence of high cobalt-containing alloys (e.g. stellite) in the primary system in the hard-facing alloys used in applications requiring resistance to mechanical wear have been associated with

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general radiation field buildup in BWRs, EPRI studies have shown that valve wear is the dominant out-of-core source of cobalt and in-core cobalt sources, (e.g. cobalt alloys in pins and rollers of control blades), contribut_e up to 75% of the total cobalt-60 inventor The licensee has initiated a cobalt reduction program. Although cobalt alloys were still used in the pins and rollers of Unit l's control blades, the licensee had replaced cage and plug assemblies of FW regulating valves with 420 series stainless steel during 198 The replacement of the Number 6 stellite cage and plug assemblers with 420 series stainless steel should reduce the cobalt content 1-the Unit 1 F EPRI recommends that FW quality be maintained as high as possible during operation with particular attention to minimizing corrosion product ingress which forms hot spots in crud traps. EPRI also re-commends that reactor water conductivity should be kept below pS/c From 1984-86, the licensee consistently kept reactor water conductivities during operation below 0.2 uS/cm. The licensee's deep bed demineralizers are less efficient at removing insoluble corrosion products than filter-demineralizers (e.g. "Powdex" systems).

However, FW recirculatiin during startup, careful resin ultrasonic cleaning and close surveillance of FW insoluble corrosion products allowed the licensee to average about 2 ppb insoluble corrosion pro-ducts in the FW during the same period. This average is below EPRI and Fuel Warranty action levels and exceeds the recommended "achiev-able valves" by a factor of The operating practice of weekly power reductions (for surveillance activities) is believed to be the reason that average values were above " achievable values".

6.0 Sampling / Measurement The licensee's sampling and inline measurement program for determining possible chemical contaminants in high purity reactor water and systems supplying makeup and cooling water was reviewed relative to commitments in the UFSAR and industry-consensus standards and recommendations. The licensee's Turbine and Reactor Building sample hoods were reviewed. The inspector noted that the sampling design'was consistent with designs for 1960's vintage plants although additional sampling capabilities (including

" corrosion product" samplers) and upgraded inline instrumentation (includ-ing lower range conductivity cells) had been added. All conductivity cells were temperature compensate Within the scope of this review, no problems or concerns were note . Implementation The licensee's implementation of the Unit I water chemistry control pro-gram was reviewed relative to Technical Specifications, commitments in the UFSAR, recommendations and guidance in NRC Regulatory Guides and Informa-tion Notices and industry - consensus standard .

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7.1 Surveillance The licensee is required to determine the conductivity and chloride ion concentration in the reactor coolant water and maintain those parameters within limits dependent upon operating conditions. In addition, remaining ion exchange capacity of the anion resins in the condensate demineralizers must be calculated and logged. Routine surveillance records and logs of those measurements during 1985-87 were reviewed and no violations were note The licensee's implementation of general chemistry sampling and analyses activities for dissolved oxygen, silica, total FW 1ron and total FW copper was reviewed for the same time period. No problems were noted. Routine surveillance activities were completed as des-cribed in licensee procedures and concentrations consistent with Fuel Warranty and EPRI guidance were usually demonstrated. Average valves for conductivity, chloride, silica, pH, dissolved oxygen and total copper consistently met EPRI achievable values for reactor coolant water, FW and CRD cooling water. As previously noted,_ total FW iron exceeded the FW EPRI achievable value of 1 pp .2 Hydrogen Water Chemistry (HWC) Test The licensee is planning a HWC Test for September - October 198 The licensee plans to determine the " mitigation point," (-0.230 volt corrosion potential for 304 stainless steel), for hydrogen gas FW feedrates to control Intergranular Stress Corrosion Cracking (IGSCC).

The mitigation point, site wide radiation levels and offgas release rates will be determined during that tes .3 Turbine Examinations Low pressure turbine examinations conducted by the licensee showed no evidence of problems from carry-over of corrosive materials in the steam. No deposits of corrosion products were noted at the " Wilson Line," (i.e. transition from dry to wet steam). No evidence of corrosion cracking was noted on the turbine buckets and wheel .4 Chemical Decontamination In 1984, the licensee conducted a partial reactor coolant system, (i.e. recirculation pipe), decontamination using the London Nuclear CanDecon Process. Discussions with the licensee indicated that a decontamination is planned for the 1987 Unit 1 outage. As noted earlier, the licensee has a radiation field buildup survey program in place to monitor the success of the decontaminations and the rate and extent of recontamination. Possible post-decontamination passiva-tion of the pipe surfaces with the General Electric Zine Injection Process was also being considere .

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7.5 Condenser Problem Although titanium tubes are used in the Unit 2 and Unit 3 condensers, Unit l's condenser tubes remain copper-nickel alloy. Condenser in-leakage rates were estimated to be approximately 130 standard cubic feet per minute and seawater intrusions are common. The resulting contamination of the FW upstream of the condensate demineralizers results in higher than average BWR FW conductivities and other chemi- l cal parameters. Although the deep-bed condensate demineralizers l provide good quality FW to the reactor vessel, failure of one or '

more demineralizers could result in chemical intrusions to the re- l actor vessel similar to those experierced in the 1970's. The lic-ensee is considering replacement of the Unit I condenser tubes with titanium. The schedule for replacement had not been determine .6 Licensee Event Report (LER) 85-009-01)

On August 13, 1985 at 1207, a Unit i reactor scram occurred which was initiated by Main Steam Line "Hi-Hi" radiation level. The scram was attributed to a corrosion product release in the FW system when the

"C" demineralizer was returned to service following a routine ultra-sonic cleaning process. The licensee surmised that the corrosion products, after passing through the reactor core, were detected as an increasing radiation level by the Main Steam Line radiation monitor The radiation monitors' normal function is to detect gross fuel failur On February 21, 1987 at 1025, a high steam tunnel radiation condition occurred which initiated Stand-By Gas Treatment (SBGT) system actua-tion. The radiation condition occurred when the "B" demineralizer was placed in service following a visual check of resin level in the Regeneration Room and return to the "B" demineralize The licensee attributed this problem to the introduction of air into the reactor resulting from incomplete air removal following the transfer and venting operations. The licensee reasoned that the introduction of oxygen caused a sudden increase in the Nitrogen-16 levels in the steam line. Although the events in LER 85-009-01 were somewhat similar to those on February 21, 1987, the licensee was convinced that the causes of the radiation spikes were differen . Exit Interview The inspector met with the licensee's representatives (denoted in Detail 1) at the conclusion of the inspection on February 27, 1987. During the meeting, the inspector summarized the purpose and scope of the inspection and identified findings as described in this repor At no time during this inspection was written material provided to the licensee by the inspector. No information exempt from disclosure under 10 CFR 2.790 is discussed in this report.