IR 05000295/1988024
| ML20206J208 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 11/22/1988 |
| From: | Holtzman R, Schumacher M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML20206J195 | List: |
| References | |
| 50-295-88-24, 50-304-88-24, NUDOCS 8811280097 | |
| Download: ML20206J208 (12) | |
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U.S. NUCLEAR REGULATORY C0ffilSSION
REGION III
Reports No. 50-295/88024(DRSS); 50-304/88024(ORSS)
Docket Nos. 50-295; 50-304 Licenses No. DRP-39; ORP-48 Licensee:
Commonwealth Edison Company Post Office Box 767 Chicago, IL 60690 Facility Name:
Zion Nuclear Generating Station, Units 1 and 2 Inspection At:
Zion Site, Zion, IL 60099 Inspection Conducted:
October 24-28, 1988 (0nsite)
October 15, 1987 (Telephone conversation)
Inspector:
R B t
M'^
/ V22/ff Date Accompanied By:
R. Bocanegra
~7//.)cbuncbv g,g Approved By:
M. C. Schumacher, Chief Radiological Effluents and Date Chemistry Section Inspection Summary Inspection on October 24-28, 1988 (Reports No. 50-295/88024(DRSS);
50,304/88024(DRSS))
Areas Inspected:
Routine announced inspection of: (1) the chemistry program, including procedures, organization, and training (IP 84750); (2) primary and secondary systems water quality control programs (IP 84750); (3) quality assurance / quality control program in the laboratory (IP 84750); and (4) nonradiological confirmatory measurements (IP 79701).
Results:
The licensee has an extensive water quality control program that conforms to the EPRI Steam Generator Owners and Primary Systems Guidelines.
The nonradiological confirmatory measurements results were good, but demonstrated some weaknesses in the chemical measurements QA/QC program.
The licensee identified weaknesses in the measurements program and corrected them.
No violations or deviations were identified.
est1280097 esi122.
DR ADOCK 0500
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DETAILS 1.
Persons Contacted
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- G. Plim1, Station Manager, Zion Station
- T. Rieck, Services Superintendent
- R. J. Budowle, Assistant Superintendent Technical Services
- P. LeBlond, Rad-Chem Supervisor
- D. P. Hemmerle, Lead Chemist
- A. Bless, Regulatory Assurance D. Guran, Analytical Chemist K. Hiedlar, Counting Room Chemist C. Doll, Unit 2 Chemist J. Etten, Laboratory Foreman T. Nachbauer Rad / Chem Technician (RCT)
D. Mikosh, RCT 0. Fick, RCT T. Elsbury, RCT The inspectors also interviewed other licensee personnel in various departments in the course of the inspection.
- Denotes those present at the plant exit interview on October 28, 1988.
2.
Licensee Action on Previous Inspection Findings a.
(Closed) Open Item (50-295/87029-01; 50-304/87030-01):
Licensee to develop an improved procedure for systematically correcting for radiation background of the gamma-ray sp' Gamma Ray 5pectrometer ectrometers.
The procedure for this correction method, ZCP 230-3, Background Determination," Revision 0, April 19, 1988, describes the determination of the background radiation levels and when and how to correct sample counts for this backgrourd.
This procedure appears to be a suitable background correction method.
b.
(Closed) Open Item (50-295/87029-02; 50-304/87030-02):
Licensee to split with Brookhaven National Laboratory (BNL) samples of reactor coolant spiked with anions and feedwater spiked with metals, to analyze them, and to submit the results to Region III.
The licensee spiked a reactor coolant sample with fluoride, chloride and sulfate ions and a feedwater sample with iron, copper and chromium ions.
These were analyzed by the licensee and a split submitted to BNL.
The results are presented in Table 1 and the acceptance criteria in Attachment 1 (see Section 6 for discussion of the criteria).
Because the 1-2% relative standard deviations reported by the licensee appear to be low, these were increased to 5%, which appears to be reasonable for these analyses.
Sulfate was not reported by BNL.
The licensee achieved four agreements in seven comparisons.
While these results demonstrate some weakresses in the licensee's
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analytical program, most of the problems appear to have been resolved in the present interlaboratory measurements as discussed in Section 6 This item is considered closed.
c.
(Closed) Open Item (50-295/87029-03; 50-304/87030-03):
Licensee to improve the chloride and chromium analyses and to use independent control standards.
The laboratory improved the fluoride analyses as shown by improved comparisons in the present interlaboratory comparison and now uses commercial aqueous chromium standard materials (rather than those made from solid K,Cr0, which is of
uncertain composition).
The laboratory also uted control standards that are from different lots than the calibration standards.
3.
Management Controls and Organization (IP 84750)
The management structure of the Chemistry Group has been modified since the previous inspection in this areat to change the responsibilities of the the Systems Chemists (Primary and Secondary) to Unit Chemists.
A new Lead Chemist was recently appointed.
He is qualified as the "radiochemist" under the standard ANSI N18.1 and is well experienced, with a bachelor degree in biochemistry. Over a period of sever years he has held several positions in this group, most recently as the Secondary Systems Chemist.
The three experienced chemists have been shifted around to different positions.
The Analytical Chemist (laboratory chemist), a recent graduate, works with the chemist formerly in this position (now the Counting Room Chemist).
This shifting of positions gives more depth of experience, but it may weaken the expertise in a given position, and it appears to be slowing the development of the laboratory QA/QC program.
The Rad / Chem Department has 31 ANSI qualified RCTs, along with nine trainees.
The licensee appears to have resolved the long-standing problem of rotating the RCTs between chemistry and health physics; in January 1989, the technicians will be permanently assigned as either chemistry or radiation protection technicians, with 17 in chemistry.
This should result in improved technician proficiency, laboratory continuity and a reduction in the burden on the laboratory supervisors to continually track the proficiencies of a large number of technicians.
No violations or deviations were identified.
4.
Water Chemistry Control Program (IP 84750)
The inspectors reviewed the secondary water control system based on the corporate directive NO Directive N00-CY.1, "PWR Secondary Water Chemistry Control Program," Revision 0, March 22, 1988.
This is essentially a revision of the previous NSD Directive NSDD-501.
The requirements of the directive are implemented in the Procedures A0P-5.2, "Secondary System Chemistry Excursion," Revisioa 0, June 17, 1987 and in ZCP 311-1,
"Secondary System Analysis Requirements," Revision 22, April 19, 1988.
1 Region III Inspection Reports No. (50-295/87029; 50-304/87030)
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Th' requirements of the orogram are consistent with those.
the Steam e
Generator Owners' Group Secondary Water Chemistry Guidelines (EPRI SG0G),
Westinghouse Guidelines for Secondary. Side Water Chemistry, and other l
contaminant concerns. Action levels may be modified by system power
supply load conditions determined b/ the System Load Dispatcher
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(Table 3.5d in the Directive), but they may be waived only by the i
Vice Preside it-PWR Operations or the General Manager-PWR Operations.
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The primary system water control program based on Proc.edure ZCP 301-1,
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is derived from the Zion Technical Specifications and the Westinghouse
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"Cuemistry C-iteria and Specifications," Volume 5-1 (March 1977).
The
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plant is not yet committed to follow the EPRI Primary System Guidelines;
!b it does appear to be consistent with them, except the plant has no limits t
c on sulfate.
The auxiliary systems, some of which are T/S related, are
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covered in ZCP 321-1, "Auxiliary System Surveillance Requirements,"
Revision 10 February 8, 1988.
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The Makeup Demineralizer system (MUD) is being c.erhauled with the i
addition of in-line instrumentation mainly for conductivity and pH j
measurements.
A reverse osmosis system (RO) was recently added that i
removes from the lake water the non-ionic organic materials that in the
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i radiation fields of the RCS become acidic.
MUD water conductivity now runs at about 0.06 pmho/cm.
A licensee representative noted that this i
ouality water makes the secondary system water quality among the best j
in the country for plants without condensate polishers.
The secondary
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j system in-line process instrumentation monitors specific and cation t
conductivities, pH, dissolved oxygen, sodium and hydrazine in the various
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systems.
A computerized Datalogger system continuously collects, stores, l
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and plots data from the secondary system sampling panel instruments.
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Since the digitized data are retained only for a few days, and can not be
otherwise saved, the licensee is planning to interface the Dataloggers
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with the main computer to permanently store the data.
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I The licensee maintains trend charts on the various chemistry and
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radiochemistry parameters, including S/G ingress (cumulative cation l
conductivity),S/G blowdown cation conductivity vs. reactor power,
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gross beta, Xe-133, I-131, primary to secondary leakage, and average
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monthly cation conductivity.
Various levels of management review the chemistry parameters and their
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trends.
The Unit Chemists review the data and other chemists review
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miscellaneous data.
The Lead Chemist prepares a status sheet for the I
t plant morning meetii.g with a copy to Operations and the Plant Manager.
The Lead Chemist also attends the Operating Engineers meetings.
A monthly status report is submitted by the Unit Chemists which is sent.
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to the corporate Tech Center.
The Center also sends a staff member on
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an approximately weekly basis to assess the data.
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In general, the various parameters appear to be well controlled, with the trend charts showing few out-of-specification problems.
Contamination spikes appear to be associated mainly with changes in power levels.
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Th'e water quality control programs appear la be satisfactory and well run.
No violations or deviations were identified.
5.
Implementation of the Chemistry Program (IP 84750)
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The inspectors reviewed the chemistry programs, including physical facilities and laboratory operations.
Housekeeping was good and bench space was adequate for the analyses performed.
The laboratories were
well equipped.
The spectrophotometers have been mainly replaced by
Brin % ann PC 800 Colorimeters with optical fiber probe cells.
These instruments appear to be easier to handle than spectrophotometer cells
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and are more reliable.
They are used'for the silica, ammonia and hydrazine analyses.
The inspectors observed several RCTs analyze routine samples on the l
colorimeters, atomic absorption spectrophotometers, ion chromatographs, l
and the boron autotitrator.
They appeared to be generally knowledgeable about the work and followed the procedures.
They appeared to do well in the analyses.
Overall, the laboratory appeared to be adequate for the proper operation of the plant and to be operating satisfactorily.
No violations or deviations were identified.
6.
Nonradiological Confirmatory Measurements (IP 79701)
l The inspectors submitted chemistry samples to the licensta for analysis as part of a program to evaluate the laboratory's capabilities to monitor nonradiological chemistry parameters in various plant systems with respect to various Technical Specification and other regulatory and administrative requirements.
These samples had been prepared, standardized, and periodically reanalyzed (to check for stability) for the NRC by the Safety and Environmental Protection Division of Brookhaven National Laboratory (BNL).
The samples were analyzed by the licensee using routine methods and equipment.
The samples were diluted by licensee personnel es necessary to bring the concentrations within the ranges normally analyzed by the laboratory, and run in triplicate in a manner similar to that of routine samples.
The results are presented in Table 2 and the criteria for agreement in Attachment 1.
These criteria for agreement are based on comparisons of the mean values and estimates of the standard deviations (50) of the measurements.
Consideration was given to the fact that the uncertainties (SD) of the licensee's results were not necessarily representative of the laboratory's because they were obtained by one analyst over a short period of time.
Consequently, when tbt licensee 50 was less than that of BNL, and a disagreement resulted, the BNL value was substituted for that of the licensee in calculating the SD of the ratio Z (5 in
Attachment 1).
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Th' licensee also prepared two samples to be split with BNL.
To these e
were added analytes supplied by the inspectors.
Reactor _ water was spiked with the anions, chloride and sulfate, and samples of feedwater were
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spiked with copper, iron, and chromiem ions.
The licensee will determine
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the concentrations of the analytes in each and the results will be sent to Region III for comparison with the values determined by BNL.
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This will be followed under the Open Item Nos. (50-295/88024-01; 50-304/88024-01).
The licensee determined 12 analytes at thrse concentrations each.
Of the initial 36 analyses 26 were in agreement (72%).
Exclusion of the
two lower-level boroa disagreements results in a somewhat improved 76%
agreement (see below).
The two higher-level chloride, the sulfate,
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silica, iron, chromium and lithium analyses had substantial biases, which indicate possible problems with the calibration standards.
Reruns of the silica, chromium, lithium and iron (by AA/ flame, rather than AA/ furnace)
were in agreement or much improved, indicating that the calibration standards were correct.
l The boron analyses of the two lower-level samples showed low biases of about 4% and of the higher-level samples, 2%.
These biases are
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substantial when consideration is given the inherently high precision of the analytical method and the importance of the results to reactor
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operations, especially in a PWR.
In this case the licenses used a
dead-stop endpoint of pH 8.6.
Similar negativo biases were observed
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at other licensees in Region III.
The source of the bias has not yet been ascertained; the inspectors will try to resolve this problem prior
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to subsequent inspections.
Even when the laboratory achieved agreement, some of the analyses
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exhibited substantial biases, such as the chloride, (two of three results 10% high), sulfate, 12-19% high, iron by furnace greater than 20%, and i
j silica, about 8% low.
Some of the other analytical problems for chromium and lithium appear to have been resolved on reanalyses. The problems in
achieving agreements and the biases indicate weaknesses in the quality control system (Section 7).
Resolution of the problems with the sulfate, i
j iion and silica analyses will be followed in subsequent inspections under j
Open Item Nos. (50-295/88024-02; 50-304/88024-02).
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Overall, the results of the analysos were good.
Laboratory personnel
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demonstrated a willingness and good ability in determining the causes of the disagreements.
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j No violations or deviations were identified.
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7.
Im)1ementation of the QA/QC Program in the Chemistry Laboratory
(I) 847501
The inspectors reviewed the nonradiological QA/QC program in the laboratory.
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The program is required by the corporate directive, Nuclear Stations O.emistry Quality Control Program, NSDD-25, January 1987, and implementrd
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in'the procedures for the various analyses.
A licensee representative stated that laboratory personnel are writing a more comprehensive procedure to deal with the operation of the Q': program.
The QC program has progressed since the previous inspection in this area.3 The use of multiple standards has been implemented with performance check standards being from different lots than the calibration standards.
The control charts have calculated statistical parameters with two-SD control limits, and thej cover most of the analyses, including fluoride, chloride, sulfate, ammonia, hydrazine, boron, lithium, silica, copper, iron, chromate, and magnesium.
The inspectors had some concerns that the supervisors did not regularly evaluate the charts to maintain control of the analyses.
Some of the charts showed substantial drifts in the data, e.g., sequential data points weru either mostly substantially above or below the mean line, and in others the limits were not recal.dlated frequently so that the control parameters did not represent actual coeration of the respective analysis, i.e. the variabilities of the data were substantially lower than indicated by the control limits.
More p,'nts were plotted on the charts than previously noted, but the charts were removed from the laboratory after completion, so that a long-term picture was not available to the analyst.
Laboratory personnel noted the inspector's suggestion that one or more completed charts (original or photocopy) remain with the inctrument.
The laboratory maintains a nonradiological interlaboratory comparison program managed by the corporate Technical Support Center (TSC) which quarterly supplies unknowns to be analyzed by the laboratory.
A review of the data from the first quarter of 1987 through the the second quarter of 1988 showed a variable, but increasing fraction /,75-100%) of the results falling within 110% of the known value, the present acceptance criterion used in the program.
The licensee's technician (RCT) performance program is operated under Procedure ZCP 1021-3, "Radiation Chemistry Technician Proficiency Check Program," Revision 1, November 4, 1987, revised since the last inspection.
The acceptance criteria are not fixed, but determined by supervision, presently set at 110% for most analyses.
This requires the testing of the RCTs twice yearly.
The first set with five unknowns has been completed and the second with three is in progress, The RCTs have done well in this program.
This program appears to be satisfactory, but the data do not appear to be collected, tabulated, and evaluated in a timely manner.
The burden of testing should be lessened when the Rad-Chem Department is reorganized (Section 3).
The licensee's QA/QC program has progressed only slowly since the previout inspection.2 Part of the problem appears to be the lack of effort given this program, one chemist with many othe' duties.
Additionally, this problem may have been exacerbated by the turnover of the staff responsible for the program, i.e. two chemists have had this program in the last year.
Licensee representatives noted that they will consider increasing the effort in this area.
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Progress of the QC program will be followed under Open Item Nos. (50-295/83024-03; 50-304/88024-03).
No violations or deviations were identified.
8.
Audits and Appraisals (IP 84750)
The inspectors reviewed corporate audit reports relating to Chemistry for 1988 and 1986.
The veports reviewed includeo QAS-22-88-80, QAS-22-88-076, QAA-22-88-02, and Q.A 22-86-II.
The audits appeared to adequately probe for progracmatic weaknesses and to assess the quality of the chemistry program.
Several findings were identified and corrected in a timely and technically acceptable manner.
No violations or deviations were identified.
9.
Open Items Open items are matters which have been discussed with the licensee, which will be reviewed 'urther by the inspector, and which involve some acticn on the part of the NRC or licensee, or both. Open items disclosed during the inspective) are discussed in Sections 6 and 7.
10.
Exit Interview The scope and findings of the inspection were reviewed wit.'. licensee representatives (Section 1) at the conclusion of the inspection on October 28, 1988.
The inspectors discussed the Open items in Section 2 and observations on the quality control program and the confirmatory measurements.
Licensee representatives agreed to consider modifications of the program, as discussed in Section 7.
The inspectors noted that while the QA/QC program has improved since the previous inspection, progress appears to have been slow due to insufficient effort put into the program (Sections 3 and 7).
During the exit interv'ew, the inspectors discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspectors during the inspection.
Licensee representatives did not identify any such documents or processes as proprietary.
Attachments:
1.
Table 1, Nonradiological Interlaboratory Split Sample Results, October 9, 1987 2.
Table 2, Nonradiological Interlato story Test Results, October 24-28, 1938 3.
Attachment 1, Criteria for Comparing Analytical Measurements (Nonradiological)
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TABLE 1 Nonradiological Interlaboratory Split Sample Results Zion Nuclear Generating Station October 9, 1987 a
c Anal-Matrix Analysfs NRC Licensee Ratio Comparf-yte Method son Y 1 SD X 1 SD Z 1 SD 12 SD Concentration, ppb
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F RCS SIE 49 + 0.7 47 + 3 0.957 + 0.025 A IC 49 1 0.7 53 1 3 1.082}0.063A C1' RCS SIE 53 + 3 62 + 4 1.170 + 0.100 A IC 533 3 44 1 3 0.82310.060D Fe FW AAS/FL 488 + 24 440 + 22 0.902 1 0.060 A Cu FW AAS/FL 513 + 26 i12 1 30 0.803 + 0.059 0
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Cr FW AAS/FL 508 1 25 427 1 21 0.841 + 0.058 D a.
Hatrix:
RCS Reactor Coolant System FW Feedwater b.
Analytical method:
IC Ion chromatography AAS/FL Atomic abso'otion/ Flame c.
The relative standard deviation is assumed to be + 5% for each of
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the analyses.
d.
Comparison:
A Agree D Disagre '
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TABLE 2 Nonradiological Interlaboratory Test Results Zion Nuclear Generating Station, Units 1 and 2 October 24-28, 1988 Anal-Analysfs NRC Licensee Ratio Compagi-yte Method son Y + SD X + SD Z 1 SD 12 SD Concentration, ppb Fluoride SIC 45.0 + 4.0 41.9 + 3.8 0.931 + 0.118 A 84.C T 1.6 81.3 T 1.9 0.961 7 0.029 A 165
162 {4 0.97830.031 A Choride IC 9.25 + 0.05 9.20 + 0.30 0.995 + 0.033 A 18.6 I 0.3 20.7 7 3.3 1.110 T 0.178 A 38.2 1 0.6 41.5 1 0.3 1.08510.024 D*
Sulf-IC 9.75 + 0.70 10.90 +
0.60 1.118 + 0.101 A ate 19.2 T 1.4 21.9 7 2.3 1.144 T 0.145 A 39.0 11.2 46.3 1 0. 6 1.187I0.050 0*
Sil-Color 105.6 + 5.6 97.5 + 1. 2 0.923 + 0.050 A ica 208
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0.913 7 0.050 A*
314
266
0.911 7 0.016 D*
(rerun)
314
306
0.97530.031 A Fe AA/Fu 9.30 + 0.25 13.5 + 1. 7 1.452 + 0.187 0 19.9 7 0.25 25.9 71.7 1.302 7 0.087 0 29.2 7 0.8 35.0 I 8.8 1.197 7 0.302 A AA/FL 744 7 20 802 T 46 1.078 T 0.068 A (rerun)
1592 320 1580 114 0.99210.il5 A Cu AA/Fu 10.0 + 0.2 9.67 + 1.20 0.967 + 0.121 A 20.2 7 0.8 19.3 7 4.2 0.958 T 0.211 A 30.0 l0.8 29.3 33.1 0.97710.106 A Cr AA/F1 49.5 + 1.2 47.8 + 0.5 0.966 + 0.026 A 96.2 71.3 103
1.070 7 0.020 D*
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159 I3 1.097 7 0.028 0 (rerun)
96.2 7 1.3 101
1.049 7 0.023 D*
(rerun)
145
147 7,7 1.01410.050 A Na AA/F1 30.2 +
3. 5 33.7 + 1. 8 1.114 + 0.142 A 53.0 I 3.0 56.5 7 0.4 1.066 7 0.061 A
3 4.5 80.9 13.5 1.02410.073 A Li AA/F1 788
+ 16 742
+4 0.942 + 0.027 0*
1200 7 28 1141
0.951 i 0.031 A*
1652 T 40 1516 I 9 0.9'.8 7 0.031 0*
(rerun)
788 T 16 775 i1 0.983 7 0.020 A 1200 7 28 1199
0.999 7 0.023 A 1652 3 40 1588
0.96110.233 A
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Anal-Analysfs NRC Licensee Ratio Compapi-yte Method son Y + SD X + SD Z + SD
+2 SD NH Color 520
+ 25 517
+ 15 0.994 + 0.056 A
1500 i 15 1580 7 38 1.053 7 0.027 A 2460 1115 2590
}25 1.05310.050 A Hydra-Color 19.9 + 03 20.2 + 0.4 1.015 + 0.025 A zine 49.9 7 0.5 52.0 7 1.0 1.042 T 0.023 A 100
104
1.040}0.023 A Concentratiun, ppm Boron Titt 1040 + 10 999
+3 0.961 + 0.013 D*
3089 7 41 2971 T 15 0.962 7 0.018 D*
5000 } 90 4883
}17 0.977}0.018 A l
a.
Value + standard deviation (50); number of BNL analyses is 6 to 9.
The number of licensee analyses is 3.
b.
Analytical methods:
Titr - titration IC
- Ion chromatography j
Color-Colorimetric probe L
SIE - Specific ion electrode AA/Fu-Atomic absorption Spectroscopy
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(furnace)
l AA/FL-Atomic absorption Spectroscopy (flame)
c.
A = Agreement
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0 = Disagreement i
Substituted the BNL uncertainty for licensee's uncertainty.
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ATTACHMENT 1 l
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Criteria for Comparing Analytical Measurements i
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This attachment provides criteria for comparing results of the capability tests.
The acceptance limits are based on the uncertainty (standard deviation) of the
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ratio of the licensee's n.ean value (X) to the NRC mean value (Y), where j
(1) Z = X/Y is the ratio, and (2) S is the uncertainty of the ratio determined from the pfopagationoftheuncertaintiesoflicensee'smeanvalue, i
S, and of the NRC's mean value, S.1 Thus, l
x y
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S*
S*
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I Y~Y*h,sothat l
z x
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+1D (3*2 I
S=Z*1 (X2 Y2)
Z
l The results are considered to be in agreement when the Lias in the ratio (absolute vtlue of difference between unity and the ratio) is less than or j
T equal to twice the uncertainty in the ratio, i.e.
l 1-Z l 1 2*Sz*
l 1.
National Council on Radiation Protection and Measurements,
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A Handbook of Radioactivity Measurements Procedures, NCRP Report No. 58, Second Edition, 1985, Pages 322-325 (see
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i Page324).
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