IR 05000348/1986001

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Insp Repts 50-348/86-01 & 50-364/86-01 on 860121-24.No Violations or Deviations Noted.Major Areas Inspected:Plant Chemistry
ML20214D432
Person / Time
Site: Farley  Southern Nuclear icon.png
Issue date: 02/11/1986
From: Cline W, Ross W
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20214D422 List:
References
50-348-86-01, 50-348-86-1, 50-364-86-01, 50-364-86-1, GL-85-02, GL-85-2, NUDOCS 8603050173
Download: ML20214D432 (10)


Text

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FEB 121986 Report Nos.: 50-348/86-01 and 50-364/86-01 Licensee: Alabama Power Company 600 North 18th Street Birmingham, AL 35291 Docket Nos.: 50-348 and 50-364 License Nos.: NPF-2 and NPF-8 Facility Name: Farley Units 1 and 2 Inspection Conduc d: January 21-24, 1986 Inspector: ff'! e s' E d A /d Dat Si ned

Approved by: < 4 / 446 W. I. Cline, Section Chief

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Emergency Preparedness and Radiological Protection Branch SUMMARY Scope: This routine, unannounced inspection involved 31 inspector-hours onsite in the area of plant chemistr Results: No violations or deviations were identifie DR 86021D ADOCK 05000348 PDR l

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REPORT DETAILS Persons Contacted Licensee Employees

*J. D. Woodard, Plant Manager D. N. Morey, Assistant Plant Manager
*C. D. Nesbitt, Technical Manager
*W. R. Bayne, Chemistry and Environmental Supervisor

. *R. T. Wood, Plant Chemist

"T. K. Osterholtz, Specialist, Safety, Audit, and Engineering Review T. Livingston, Chemistry Foreman R. Robinson, Chemistry Foreman Other licensee employees contacted included chemistry technician NRC Resident Inspectors W. H. Bradford
*B. R. Bonser
* Attended exit interview Exit Interview The inspection scope and findings were summarized on January 24, 1986, with those persons indicated in Paragraph 1 above. The inspector described the areas inspected and discussed in detail the inspection finding No dissenting comments were received from the license The licensee did not identify as proprietary any of the materials provided to or reviewed by the inspector during this inspectio . Licensee Action on Previous Enforcement Matters This subject was not addressed in the inspectio . Unresolved Items Unresolved items were not identified during this inspectio . Plant Chemistry (79701 and 79502)

As a result of its continuing concern for steam generator tube integrity, the NRC staff has recently issued recommended actions and review guidelines that are directed toward the resolution of unresolved safety issues regarding this subject (see Generic Letter 85-02 dated April 17, 1985). One recommended action is as follows:

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" Licensees and applicants should have a secondary water chemistry program (SWCP) to minimize steam generator tube degradation. The specific plant program should incorporate the secondary water chemistry guidelines in the Steam Generator Owners Group (SGOG) and Electric Power Research Institute (EPRI) Special Report EPRI-NP-2704, "PWR Secondary Water Chemistry Guidelines," October 1982, and should address measures taken to minimize steam generator corrosion, including materials selection, chemistry limits, and control method In addition, the specific plant procedures should include progressively more stringent corrective actions for out-of-specification water chemistry condition These corrective actions should include power reductions and shutdowns, as appropriate, when excessively corrosive conditions exist. Specific functional individuals should be identified as having the responsibility / authority to interpret plant water chemistry information and initiate appropriate plant actions to adjust chemistry, as necessar The reference guidelines were prepared by the Steam Generator Owners Group Water Chemistry Guidelines Committee and represented a consensus opinion of a significant portions of the industry for state-of-the-art secondary water chemistry control ."   l Reference Section 2.5 of NUREG-0844 In parallel action, the NRC Office of Inspection and Enforcement has developed two new Inspection Procedures to verify that the design of a plant provides conditions that ensure long term integrity of the reactor coolant pressure boundary and to determine a licensee's capability to control the chemical quality of plant process water in order to minimize corrosion and I occupational radiation exposur l The objectives of these new procedures were partially fulfilled during previous inspections (See Inspection Reports 50-348,364/84-09 and 50-348,364/85-19 dated April 18, 1984, and April 25,1985). During this inspection, Unit I was operating at full power in its l seventh fuel cycle that begun in May 1985 and is scheduled to end in September 1986. Unit 2 is in its fourth fuel cycle that will end in April 1986. To date, both units have operated at, or close to, full I power except for three or four trips caused primarily by electrical transients. As will be discussed later, the licensee reduced the power of Unit 1, as the result of an abnormal secondary chemistry event, for ,

two days early in January 1986. This chemistry related transient, and ' a less severe contamination of the secondary coolant in Unit 2 later in January 1986, were the only two periods when the licensee did not have good control over the chemistry of both the primary and secondary chemistry systems - once the units became stable after startup in their current cycle . .- -. - - . - .-. . -- .. .- - ---

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A brief resume of the operational experience with the major components l of the secondary system during the current fuel cycles is presented i below
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(1) Integrity of the Main Condenser j  ;
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An audit of data obtained by the licensee since the last inspection showed that no inleakage of condenser cooling water had ! , occurred and the ingress of air had been maintained at <1 standard j cubic foot per minute. Although the licensee believes there must j be as very small inleakage of air under the water in the

condenser, contamination of the secondary coolant by this most l

prevalent pathway is being kept lower than any other nuclear plant > ] in Region II. As a consequence, the purity of the water in the . hotwell was very high and improved with time throughout the fuel l ]

cycles; i.e. , cation conductivity decreased from ~0.3 umho/cm to
 ~0.15 umho/cm.

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! (2) Contamination From Condensate Makeup

' Since both units require water to replace that lost through blowdown (Unit I continually wastes blowdown and Unit 2 wasted j blowdown from March through Ju1e 1985) as well as from other ! causes, this makeup water is considered the second most likely I pathway for contaminants to enter the secondary system. A spot j audit of the operation of the water treatment plant showed that i 1.6x10' gallons of water had been required during September 1985

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when both plants were operating at ~100". power. This purified I water is initially stored in two condensate storage tanks (CST) that are designed to minimize further contamination by air i inleakage. Again, an audit of September 1985 data showed that the l purity of the product water (as shown by pH, conductivity, j dissolved oxygen, silica, and sodium) had been maintained at a

;  high level, i  During this inspection, the inspector was informed of two recent events that resulted in contamination of the product of the water #

treatment plant with sodium ions. Both events occurred while the demineralizers in the water treatment plant were being regenerated l with dilute sodium hydroxide solutions. As a result of the first

;  incident in Unit 1, the sodium concentration in the CST increased

, to >400 pp The sodium concentration of the steam generator , blowdown exceeded 100 ppb, the Action 2 level specified in procedure FNP-0-AP-76 (Conduct of Operations Chemistry and , Environmental Group), and forced the licensee to reduce power to . 40*4 for approximately two days until the sodium concentration could be reduced below this action level limit by means of steam

,  generator blowdown. Although the water in the CST for Unit 2 was
;  also contaminated, no action level was exceeded for this Uni I
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While the licensee was reducing the level of contamination in both , CSTs, by bleed and feed methods, makeup water to Unit 2 was being provided directly from the discharge of the water treatment plan During this period and while the demineralizers were again being regenerated, the sodium concentration of the makeup water and the steam generator blowdown increased to ~150 ppb and 15 ppb respectively. No action level was exceeded howeve The licensee informed the inspector that both of these transients were suspected as being caused by leakage of the regenerated sodium hydroxide solution into the product stream when the water treatment process is being restarted after the regeneration phase has been terminated. The licensee is concerned that this leakage has been occurring in the past but has not been identified as long as the product water was pumped into, and diluted by, the water in

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the CST. It was only when the CST was being bypassed that this

 ' slug' of sodium hydroxide caused a detectable increase in sodium concentratio On the basis of this theory, the licensee is trying to determine how the design of the water treatment plant discharge can be modified to eliminate the leakage of sodium hydroxide after each regeneration phas (3) Purity of Feedwater The inspector reasessed the licensee's capability to ensure that the quality of the feedwater could be maintained in a manner that would prevent damage to the steam generator tube These two Farley units remain unique among the PWRs in Region II inasmuch as the elimination of soluble or insoluble impurities in the secondary coolant can be achieved only through blowdown of the steam generators;   i.e., there is no condensate polishing capability. Consequently, any impurity in the condensate will be transported to the steam generator. The solid oxides of iron and copper that may be dislodged from the high pressure steam and condensate drain lines, especially after an extended outage when these large carbon steel pipes are exposed to air, will also be transported, via the high pressure feedwater drain to the steam generator As discussed in the report of the last inspection, all copper alloy heat exchanger tubes had been replaced with stainless steel

! when Unit 1 began its current fuel cycl The licensee plans to replace all remaining copper alloy tubes in the secondary side of Unit 2 during the upcoming refueling outage in April 198 Consequently, the transport of copper oxide will be significantly reduced or eliminated in the future. In the meantime, the l licensee monitors the feedwater of both units for copper, but ' normally cannot detect its presenc , The licensee continues to apply a ' chemistry hold' on reactor power to ensure that the quality of the feedwater meets specified l __ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ - _ - _ -

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limits before the power is raised above 5% after a shutdown, and above 30% when the drains of the feedwater heaters are pumped forward. Action levels are based on excessive levels of oxygen, hydrazine and specific conductivity in the feedwate During the audit, the inspector observed that approximately two to three weeks were needed to attain stable operational and chemistry control of both units during the startups of the current fuel cycles. The licensee informed the inspector that attempts will be made to reduce future refueling outages to 30 days or less. As this outage time decreases, less time will be available for cleaning the secondary system before reactor heatup; therefore, increased effort should be made to minimize the admission of air r into the secondary side and thus, minimize the deterioration of

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the passivating layer of magnetic on the inner surfaces of the pipe A comparison of the purity of the condensate and feedwater for i Unit 1, since the beginning of the current fuel cycle, showed that very little contamination of the feedwater was being incurred due to the heater drains; i.e., the cation conductivities in the condensate and feedwater were essentially the same and continually decreased with operational tim (4) Condition of the Steam Generators ' During the sixth refueling outaga for Unit 1 in April 1985, the licensee investigated the amount of potentially corrosive materials in each of the three steam generators and performed eddy current tests on the steam generator tubes to establish their integrit The inspector established that relatively large amounts of solid material was removed from all three steam generators, i.e., 1000 lbs. of metal (iron and copper) oxides. As r this Unit cooled down for the outage, hideout return studies indicated that significant quantities of such potential corrodants as sulfate, chloride, and fluoride, as well as silica and cations such as sodium, magnesium, and calcium, were captured within the oxide sludge. Most of these ' hideout' species were removed with the sludge and through subsequent flushes of the steam generator; however, the licensee observed that significant amounts of sulfate (~100 ppb) remained in the steam generators af ter the cold water flushes. It is evident that the most efficient manner to remove

' hideout' is when the steam generator water is 200* to 400* The licensee continues to add boric acid to the feedwater of Unit 1 (~5 to 10 ppm boron in the blowdown), and the blowdown from this Unit is wasted. The blowdown from Unit 2 was also wasted until July 1985; subsequently, the blowdown has been filtered and cycled to the hotwel ,
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The inspector observed the cation conductivity of the steam that is generated in both units normally approximated that of the condensate /feedwater (i.e., 0.2 umho/cm). Also, only ~50 percent of the cation conductivity of the blowdown can be accounted for from the concentrations of sulfate, chloride, and fluoride (or any other anion that can be detected by means of ion chromatography).

The licensee is attempting to identify all organic or inorganic species that may be contributing to the cation conductivity of the blowdown and to determine what species are being volatilized with the stea (5) Integrity of the Low Pressure Turbines The licensee did not inspect the low pressure turbines in Unit 1 during the April 1985 refueling outage but plans further inspections during the September 1986 outag Both low pressure turbines in Unit 2 will be inspected after the current fuel cycl Inasnuch as the licensee has replaced the original disks with the

'heasy' disks now manufactured by Westinghouse, fewer, if any, indications of bore or key-way cracking are anticipated from either chemical or metallurgical causes, b. Implementation of the Secondary Water Chemistry Program By letter dated June 14, 1985, the licensee responded to the Office of Nuclear Reactor Regulation's Generic Letter 85-02. In its response, the licensee stated that the Farley secondary water program had incorporated the original SGOG guidelines, with exceptions, and the program was being reviewed and revised to incorporate more guidelines that had been recommended in the revised SGOG guidelines. In a reassessment of the licensee's program, the inspector reviewed recent revisions of the following key administrative and chemical procedures:
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FNP-0-AP-1 Development, Review, and Approval of Plant Procedures, Rev. 19, 11/13/85

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FNP-0-AP-3 Plant Organization and Responsibility, Rev. 6, 2/4/85

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FNP-0-AP-45 Farley Nuclear Plant Training Plan, Rev. 7, 5/15/85

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FNP-0-AP-76 Conduct of Operations Chemistry and Environmental Group, Rev. 1, 7/9/85

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FNP-0-CCP-201 Schedule, Chemistry, and Water Treatment Plant Activities, Rev. 3, 10/22/85

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FNP-0-CCP-202 Water Chemistry Specifications, Rev. 3, 8/12/85

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FNP-0-CCP-204 Calibration and Control of Chemical Analysis Instruments, Rev. 1, 10/4/85

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l Administrative Procedure FNP-0-AP-76 defines the organization, l responsibilities, and administrative duties that are required to l establish and maintain a water chemistry program. This procedure also , provides the technical guidelines and limits that are needed to l minimize impact on the power plant and on the steam generators in , particula This and other Administrative Procedures have been I approved by the Plant Manager as well as by a Senior Vice President of I the Utility and the Corporate Manager of Safety, Audit, and Engineering Review, and thus, represent plant and corporate policy. The Chemistry and Environmental Group has used these policies to develop a lower tier of control and diagnostic procedures that are applicable to all modes of plant operations. Through discussions with Chemistry supervisory personnel and technicians, the inspector established that these people are cognizant of the current understanding of corrosion mechanisms and the guidance provided by the SGOG and the NSSS vendor (Westinghouse).

The licensee's capability to implement its water chemistry program was reviewed and is summarized belo (1) Staffing

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The chemistry staff currently has four less technicians than l required to maintain the desired five crews of four peopl Consequently, plans are being made to reschedule chemistry activities on the basis of four crews. Each crew has at least two technicians who qualified to meet ANSI standard The principal responsibilities of each crew are related to the following: ' primary chemistry, steam generator blowdown chemistry, and auxiliary systems; water treatment plant; boric acid station; secondary chemistry; and sewage treatment plan Support is ! provided in such areas as quality control and development of instrumental analysis techniques by 'anomoly technicians' who I report to the Plant Chemist. The licensee informed the inspector l that each Chemistry Technician has an academic degree in a j scientific discipline, predominantly in chemistry, and has been on I the chemistry staff for two years or longer.

l (2) Training l l Procedure FNP-0-AP-45 establishes the criteria of training programs that must be completed by Assistant Chemistry Technicians and Chemistry Technicians wiftnin three years af ter assuming these position Formal training and retraining is provided at the i on-site Training Center where state-of the-art facilities and l analytical instrumentatien are available. As long as only four I crews are svailable, work schedules are being overlapped so that ' 16-hour periods of t. raining may be periodically give (3) Laboratories The licensee uses a single laboratory for surveillance and control of the secondary water chemistry of both unit Most of the

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primary water chemistry control, as well as the sampling and analysis of steam generator blowdown is performed in the primary water laboratory in each unit. During this inspection period, the Unit 1 primary water laboratory was not being used because of problems with sink drains. Most of the licensee's analytical instrumentation is located in the primary water laboratorie In addition to having the capability to take ' grab' samples, in the Secondary Water Laboratory, from key locations through the condensate /feedwater chain, the licensee also has a panel where i inline instrumentation monitors dissolved oxygen, cation conductivity, ard specific conductivit The inspector was informed that the instruments on these panels are to replaced with i digital recorders during the next refueling outage for each uni The inspector questioned the efficiency of monitoring the steam generator separate from the rest of the secondary water syste The licensee stated that sample taps for steam generator blowdown had been located only in the Primary Labora. tory as a precaution , against a primary to secondary leak through the steam generator ! that would result in the blowdown samples having increased , radiation level Extension of these sample lines to the l Secondary Water Laboratory was not considered to be practical l because the length of the sample lines would be excessive. As a , result of this decision, the licensee has located all sensitive l analytical instruments (i.e., atomic absorption spectrophotometer, ! flame photometer, and ion chromatographs) in the Primary Water Laboratory. At present, the only operable ion chromatograph that i is available to the Chemistry Group is located in the on-site l Training Center. The licensee, however, has purchased two ion chromatographs of a new design and plans to operate these instruments in the Primary Laborator j j (4) Maintenance of Instrumentation l l The inspector was informed by Chemistry personnel that timely l maintenance was being provided to chemistry equipment and to the ( inline monitors and the display panel. Both licensee and contract personnel are used for this purpose. The inspector observed that all inline monitors and their displays (recorders and meters) were operabl (5) Quality Control l l The inspector reviewed the licensee's procedures for calibrating analytical instrumentation and audited selected calibration data and control results. Emphasis is placed on achieving quality control through the use of ' standard samples' and standard calibration curves as well as through participation in an interlaboratory program with other Alabama Power Company facilitie Control limits are currently based on absolute _- -_-__

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values; i.e., fractions (5 or 10 percent) of the value of the control samples. The inspector established that these controls were routinely being met, Summary During this part of the inspection, the inspector did not identify any violation or deviation. Random audits of the licensee's logs verified I that Technical Specifications related to the reactor coolant had been implemented, and the limits on potential corrodants had been readily me The inspector considers the large amounts of sludge and potentially corrosive ions, sulfate and chloride, (as identified by hideout studies) to be the most significant chemistry problem faced by the ! licensee. The potentially detrimental effect of copper in this sludge should be reduced after all copper alloy heat exchanger tubes have been replaced; however, this action will not guarantee that all residual l copper will be removed during future sludge lancing The licensee recogn^ zes that the source of the corrosive anions must be identified and elt.minated and the extent of oxidation of the low- and ! high pressure carbon steel components (pipes, heater shells) must be reduced so that less sludge is generated. The licensee's capability to I detect very low concentration of anions will be significantly improved I when the new ion chromatographs are placed in use and should enhance i the capability to detect the source of sulfate and chloride as well as l to maintain these concentrations below SGOG limit Reduction of the

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mass of sludge may be more difficult since blowdown of the steam generators af fords the only means of eliminating solids from the secondary syste Consequently, the licensee must emphasize chemistry control during refueling outages or other periods of extended layup to minimize the loss of surface passivation and the subsequent formation , of non-adhensive iron oxides on carbon steel components.

I l The inspector considers the licensee to be meeting the intent of , t Generic Letter 85-02, relative to secondary water chemistry contro It was also evident that the licensee is actively attempting to remain abreast of the current understanding of corrosion mechanisms and to implement state-of-the-art techniques and procedures to maximize chemistry control.

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