IR 05000416/1985037

Insp Rept 50-416/85-37 on 851007-11.No Violation or Deviation Noted.Major Areas Inspected:Plant Chemistry & Inservice Testing of Pumps & Valves

ML20136B621
Person / Time
Site:	Grand Gulf
Issue date:	11/04/1985
From:	Cline W, Ross W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20136B615	List: IR 05000416/1985037 ML20136B611
References
50-416-85-37, NUDOCS 8511200247
Download: ML20136B621 (9)

Text

1. .pn at gD UNIT E3 STATES f NUCLEAR REGULATORY COMMISSION

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, REGION 11 l h 101 MARIETTA STREET.N.W.

t ** t ATLANTA. GEORGI A 30323

'+,.....,o l NOV 0 71985 Report No.: 50-416/85-37 Licensee: Mississippi Power and Light Company Jackson, MS 39205 Docket No.: 50-416 License No.: NPF-29 Facility Name: Grand Gulf f

Inspection ondu te - Octoberr 7-Ji[4985 Ins actor- _

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ar WY J. Ros V j /g Da W ign i /

Approved by: '/l1$ / -c '-/1. (

W. E. Cline, 'Section Chief ll7 tf

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,Date Signed Emergency Preparedness and Radiological Protection Branch Division of Radiation Safety and Safeguards SUMMARY Scope: This routine, unannounced inspection entailed 40 inspector-hours onsite in the areas of plant chemistry and inservice testing of pumps and valve Results: No violations or deviations were identified.

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REPORT DETAILS Persons Contacted Licensee Employees

• J. E. Cross, General Manager M. J. Wright, Manager - Plant Operations

• J. V. Parrish, Chemical - Radiation Control Superintendent

• A. Holbrook, Chemistry Supervisor J. C. Bryan, Chemistry Training Supervisor

• B. Wedgeworth, Chemistry Specialist M. Michalski, Radwaste Supervisor J. Malone, Inservice Testing Coordinator L. Eichenberger, performance Engineering C. Cresap, Operations Supervisor Other licensee employees contacted included chemistry technician NRC Resident Inspectors R. Butcher

• Attended exit interview Exit Interview The inspection scope and findings were summarized on October 11, 1985, with those persons indicated in paragraph 1 above. The inspector described the areas inspected and discussed in detail the inspection fir. dings listed belo 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 inspectors during this inspection. Licensee Action on Previous Enforcement Matters This subject was not addressed in the inspection. Unresolved Items Unresolved items were not identified during the inspection. Plant Chemistry (79501 and 79502)

In a recent action the NRC Office of Inspection and Enforcement has developed two new Inspection Procedures to verify that the design of a nuclear power plant provides conditions that ensure long-term integrity of the reactor coolant pressure boundary and to establish the extent to which a licensee is able to control plant chemistry so that corrosion and occupational radiation exposure are minimi:e I

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l The objectives of these new procedures were partially fulfilled during a previous inspection of Grand Gulf Unit 1 (see Inspection Report 50-416/84-44 dated December 11,1984). At the time of the previous inspection this unit

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had not commenced commercial operation. Consequently, this follow-up inspection consisted of review of plant design and the protection afforded against ingress of corrossive species into the reactor coolant. Also, the inspector evaluated both the operating experience since the unit went commercial on July 1, 1985, and the capability of the licensee to effectively control the chemistry of the reactor coolant and associated water system Plant Design (1) Integrity of the condenser The quality of water used to extract heat from the main condenser

, as well as from several closed cycle cooling systems (e.g., Closed Cycle Cooling Water, Dry Well Chill Water, Turbine Building Cooling Water, Plant Chill Water) and from the Steam Jet Air Ejector remains a concern because all of these systems use water taken from deep radial wells close to the Mississippi River. This water must be treated continuously to prevent microbiological species in the well water from inducing corrosion of the metallic (stainless steel, carbon steel, copper alloy) components and pipe in these heat transfer systems. The inspector observed that two types of chemicals were being added to the Plant Service Water to

, control s;1me, bacteria, and fungi, as well as to prevent l oxidation and coagulation of soluble iron salts in the well wate Additional biocides are added to control micro organisms in the cooling tower basin The reactor coolant boundaries of the Component Cooling Water System are protected against oxidation and corrosion by adding sodium nitrate to the Intermediate Closed Cycle Coolant. Inasmuch as glycol is used as the intermediate for the Plant Chiller systems the addition of anti-corrosion agents is not neede As the result of this chemical treatment there has not been any

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indication of degradation of the heat exchange surfaces that would result in inleakage of corrosive species from either the Condenser Cooling Water or Plant Service Water. The licensee advised the inspector that a condenser tube leak had been experienced prior to the unit becoming operational; however, the failure of the tube had been attributed to mechanical (vibration) problems rather than to corrosion. Another leaking tube was indicated by a gradual, but continuous, increase in the conductivity of the condensate during the period of this inspection. The licensee has acquired a helium leak detector and plans to search for this small leak l during a two-month maintenance outage that was to begin on l October 12, 1985. At the same time, an effort will be made to decrease air inleakage from the current rate of - 15 SCFM

, (Standard Cubic Feet per Minute).

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( In addition, the licensee is attempting to increase the electrical

, output of the unit by improving condenser vacuum. The inspector was informed that condenser vacuum was being detrimentally l

I affected by a loss in heat transfer through the condenser tubes as i

the result of slime formation on the inner surfaces of the tubes.

l The condenser was designed for the use of an Amertap cleaning system to prevent such fouling, but this cleaning system has not

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been installed. Instead the licensee is investigating the use of l additional water treatment chemicals in the Closed Cycle Cooling l

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Water to eliminate this type of foulin (2) Condensate Makeup An audit of analyses of water in the Demineralized Water Storage Tank (DWST) and in the Condensate Storage Tank (CST) indicated that water of relatively high purity was being produced in the water treatment plant for condensate makeup (i.e., conductivity of

~ 0.7 umho/cm, silica <20 ppb, chloride <20 ppb). Because of the high purity of this water and the absence of inleakage through the condenser (except since September 29, 1985) the quality of water in the condenser hotwells and in the condensate system has been only slightly less than that of demineralized water (i.e.,

conductivity of only 0.06 1 0.003 umhos) since commercial j operation began.

l l Although the CST is vented to air the concentration of dissolved i oxygen in the condensate (and subsequently in the feedwater and in l the water used for control rod drive) is maintained less than l 100 ppb by the air ejectors and condenser vacuum. This parameter i is monitored daily to ensure that the concentration of dissolved l oxygen in the reactor water is kept at a minimum level.

l l (3) Condensate Cleanup System l An audit of analyses of feedwater samples showed that the dual l

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condensate cleanup system (powder /demineralizers and deep-bed i

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resin beds) has been very effective in ensuring that only very high quality water is pumped into the reacto The conductivity of the feedwater has normally been that of demineralized water

even when the condensate became contaminated from condenser l inleakage.

During startup the licensee has been effecting cleanup with two or three powder /demineralizers in series with two to four deep bed demineralizers. The powder /demineralizers are bypassed when the i

unft reaches >25% power. As the differentf al pressure across a deep bed demineralizer increases, as the result of the resin beads

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l being coated with iron oxide, the bed is bypassed and the coatings are removed by ultrasonic cleaning. The licensee defines a deep j bed demineralizer as being operable until it is loaded with I

chloride ions to the extant of 75% of theoretical (~ 400 pounds of l

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chloride per bed). It is estimated that very little (<5 pounds)

of chloride has been adsorbed on the resins to date; consequently, !

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the beds may not have to be replaced for a significant time period. (The licensee plans to replace rather than regenerate spent deep beds; however, the powder demineralizers are recoated frequently.)

(4) Feedwater Heaters and Heater Drains i

By pumping the condensate from the high pressure feedwater heater drains back to the hotwell during plant startups the licensee was able to prevent the bulk of oxidation products from the extraction i steam lines and moisture separator reheater from contaminating the l feedwater before the plant became commercially operational. Since July 1,1985, there have not been any outages; consequently the heater drains have been pumped forward continually to provide the additional feedwater needed for full power operatio The licensee recognizes that the heater drains should not contaminate the feedwater, especially with insoluble irons oxides. Therefore, plans are being made to install a sample tap on the heater drain tank so that grab samples of the tank water can be analyzed before '

l the water is pumped to the suction of the feedwater pumps. The l plant's operating procedures provide for a hold in power ascension l until the drain water is shown to be of acceptable quality to be l used for feedwate The inspector considers that the licensee is taking appropriate actions to prevent contaminatic, of the feedwater from corrosion

! products that are formed in the high pressure steam and water regions of the reactor coolant cycle during plant shutdown (5) Reactor and Reactor Water Cleanup System

, Through effective use of the condensate polishing system to remove

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all potential soluble and insoluble corrodants from the condensate l and heater drain water, the licensee has achieved essentially pure l feedwater. Consequently, except for one day since commercial l operation began, the conductivity of the reactor water has been l maintained less than 0.20 umho/cm.

l This level of purity is well within the limit (0.30 umho/cm)

l recommended by the BWR Owners Group (BWROG) to provide immunity

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from intergranular stress corrosion cracking (IGSCC) of sensitized austenitic stainless steel, such has been observed in many Type 304 and Type 316 stainless steel piping systems in Boiling Water L Reactors (BWR).

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The inspector was informed that no problems had been encountered with the Reactor Water Cleanup System (RWCU). This system

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provides continual cleanup to ~ 1% of the inventory of reactor

water. An audit of analyses of RWCU effluent revealed that water

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of very high purity (conductivity <0.10 umho/cm) was routinely

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being produced by the RWCU demineralizer !  ;

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The effectiveness of this system in removing silica from the reactor water decreases significantly as the demineralizers age;

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, i.e. the silica in the RWCU effluent varied from >100 ppb to j

>71000 ppb. The BWROG guidelines consider a silica concentration of 200 ppb as representing a level that warrants an improvement of operating practice Other than its use as an indicator of the efficiency of the water

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treatment plant and the condensate cleanup system, the con-centration of silica in the reactor water should also be

! controlled because silica readily volati:es tith steam and l

j subsequently precipitates on the surfaces of the low pressure i

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turbine. There is insufficient operational data relative to Allis Chalmers turbines in nuclear power plants to predict the corrosive [

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effect of silica on the turbine blades or disk t i  ;

(6) Summary l

) i During the first three months of commercial operation the licensee [

has been able to keep the purity of the reactor water at a level !

j that should prevent IGSCC of the Recirculation Water Syste :

{ There has already been inleakage of air and water through the i condenser; however, the condensate cleanup system has been very a

efficien Although soluble silica is poorly adsorbed on ion .

j exchange resins of the deep bed demineralizers the licensee should !

i be able to maintain the level of silica in the reactor water i <100 pp i Reassessment of the licensee's Water Chemistry Program l

l Since the inspector's previous inspection at Grand Gulf the licensee !

j had made several changes in the Chemistry staff and the Chemistry i

Control progra The most significant of these are summarized below, i l (1) Chemistry staff

In Inspection Report 50-416/84-44 the inspector expressed concern i that the licensee was entering into the pre-operational phase of

Unit I without a Plant Chemist and with a chemistry staff that had [

i no experience with an operating nuclear plant. A Plant Chemist ,

was hired in the spring of 1985 but was soon given the additional

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duties of Acting Superintendent of Chemistry and Radiation

. Control; 1.e., responsibility for health physics activities as (

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i well as for chemistr Near to the beginning of commercial operation of the plant a new Chemistry Supervisor was appointe .

l and 'the licensee began hiring nine additional Chemistry

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Technicians. Although some of these Chemistry Technicians are e specialists who are qualified in the utilization of f

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> state-of-the-art analytical chemistry instrumentation, all of the l new people and some of the older Technicians must still be qualified in control and di3 gnostic responsibilitie Consequently, the inspector observed that a significant amount of orientation, training, and reorganization activities were in progress while the Chemistry Staff was fulfilling its surwillance responsibilities. Although there was a relatively large wmber (~ 8 to 12) of Chemistry Technicians working on the day shif t in the limited area of the Hot Laboratory, their activities were being performed in a professional manner and without confusio (The back shif ts are manned by fewer Chemistry Technicians). The inspector interviewed several Chemistry Technicians to assess

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their level of experience and understanding of the procedures they I

were performing. Some of these personnel were working as l teacher-student pairs. All indications were that the procedures were being performed correctly, and that the results were being

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reviewed by the Lead Chemistry Technician on each shift.

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The licensee has initiated a formal 17 week training course in all phases of plant chemistry, as well as for indoctrination into i other areas such as plant systems, with the goal of qualifying all Chemistry Technicians to meet the criteria developed by both ANSI

' (American National Standards Institute) and INP0 (Institute for Nuclear Power Operations). Also, another reorganization of the Chemistry Staff is under consideration whereby five Shift Supervisors would be selected to assist the Laboratory Superviso In addition, the licensee is trying to obtain another Plant Chemist to relieve the Superintendent of Chemistry and Radiation Control of his dual responsibilitie (2) Chemistry Control Program The inspector based his assessment of the adequacy of the licensee's chemistry program primarily on Procedure 08-S-03-10 Chemistry Sampling Progra This procedure was developed to

" integrate diverse portions of the chemistry program into a single document to provide guidance for the Chemist performing the sampling and analyses." At the time of this inspection this procedure was undergoing major revision. Contrary to the inspector's understanding during the previous inspection, the licensee was not aware of the guidelines for a BWR water chemistry program that had been developed by the BWR Owners' Group (BWROG)

in 1984. Consequently, the licensee's program does not reflect either management commitments or the technical basis and control requirements that have been recommended by the BWRO Although the BWROG guidelines have not been formally endorsed by the NRC (although, similar guidelines prepared for Pressurized Water Reactors have been endorsed) they are considered to

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represent a consensus of philosophy and technical understanding by the BWR segment of the electrical utility industry. As such, they are thought to provide the control needed to prevent degradation of the reactor coolant system from chemical attac The inspector verified that the chemistry control program now in use by the licensee effectively ensures that Technical Specifi-cation requirements are met. Also the corrective actions required by Operating Procedure 05-1-02-V-12 Off-Normal Event Procedure-Condensate High Conductivity provides levels of protection similar to those recommended by the BWROG. However, l the limits for key chemical parameters are not consistent between the Technical Specifications, Procedure 05-1-02-V-12 and Procedure i

08-S-03-1 Actually, the licensee has been controlling the i chemistry of the reactor water cycle better than the limits specified in these requirements or even in the BWROG guideline The licensee (both plant management and Chemistry staff) agreed to l review the BWROG guidelines and take whatever action appeared to l be appropriate to factor this guidance into the water chemistry l control program and plant procedures, l

l The inspector verified that acceptable quality control measures have been included in individual chemistry procedures. In addition, a more structured quality assurance program using inter-and intra-laboratory standards has been initiate The inspector emphasized the need for cleanliness and contamination control to ensure the validity of analyses of samples that are essentially demineralized wate The licensee is making commendable use of a new ton chromatograph for the determination of trace amounts of anions and cations and has included this instrument in the formal training course for Chemistry Technician The inspector established that analytical results have been stored

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in a computer data base and are available for short and long-term l trending. Key control and diagnostic parameters that are determined on both a daily and weekly schedule are provided daily to selected members of plant management, to the NRC Resident Inspector, and to Chemistry staff supervision.

Summary

[ The inspector expressed his concern to both Chemistry Supervision i

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and Plant Management that the full development of both the admini-strative and technical aspects of an acceptable water chemistry program had been delayed until after the plant is commercially

, operational. The perceived advantages to be gained from the BWROG

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guidelines were also stressed. However, the inspector found the licensee's control of plant chemistry to be acceptable and

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4 observed that progress was being made in many areas of supervision, training, quality control, and laboratory technique The inspector emphasized again the need for both corporate and plant management to expedite the filling of the Plant Chemist positio During this part of the inspection no violations or deviations were identifie (6) Inservice Testing of Pumps and Valves (561726)

The licensee's proposed program for testing safety related pumps and valves, to meet the requirements of Section XI of the ASME Code, and associated requests for relief from specified requirements of the code are under review by the NRC Office of Nuclear Reactor Regulation. Per a letter from NRR to the licensee dated August 14, 1985 the licensee's program and relief requests have been approved until the review has been completed or until March 31, 1986, whichever comes firs The inspector discussed with cognizant licensee personnel the scope of the ISI program and the NRC's interpretation of certain Code requirements. The licensee described the manner in which the program was being implemented and how test data were being managed per the Code requirement for summary listings for all pump and valve test result No violations or deviations were identified as the result of these discussions.