ML20197G689

Compliance Evaluation Rept Supporting Application Re Product & Tails Withdrawal Facilities Criticality Accident Alarm Sys

ML20197G689
Person / Time
Site:	07007001
Issue date:	12/07/1998
From:	NRC
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Shared Package
ML20197G687	List: ML20197G681 ML20197G689 ML20197G694
References
NUDOCS 9812100106
Download: ML20197G689 (10)

Text

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. y- J*, UNITED STATES

< e NUCLEAR REGULATORY COMMISSION f WASHINGTON. D.C. 20555-0001

% ***** [' December 7, 1998 .

DOCKET: 70-7001 CERTIFICATE HOLDER: United States Enrichment Corporation ,

Paducah Gaseous Diffusion Plant j Paducah, KY

SUBJECT:

COMPLIANCE EVALUATION REPORT: APPLICATION DATED SEPTEMBER 15,1997, PRODUCT AND TAILS WITHDRAWAL FACILITIES CRITICALITY ACCIDENT ALARM SYSTEM BACKGROUND >

By letter dated September 15,1997, the United States Enrichment Corporation (USEC) requested an amendment to the Certificate of Compliance for the Paducah Gaseous Diffusion Plant (PGDP). The request is to revise the Technical Safety Requirement (TSR) 2.3.4.7, Criticality Accident Alarm System, Required Action A.1.5, to provide additional time to operate

! the withdrawal station in normal steady state operation should the system be declared inoperable and the required actions entered. This would allow the plant to continue withdrawing l product by filling the accumulators. By letter dated February 12,1998, the staff requested additionalinformation. By letter dated March 13,1998, USEC provided a response to the staff's l questions. By letter dated July 9,1998, the staff requested further information, which was  !

l provided by USEC letter dated August 18,1998.

l TSRs in Section 2.3 cover operations in both the product and tails withdrawal facilities, however, since the tails facility does not handle uranium enriched to greater than 1 wt % 2"U,a criticality accident alarm system (CAAS) is not required. Therefore, TSR 2.3.4.7 only applies to  :

the product withdrawal area. The TSR consists of two parts. Part a applies to the detection capability of the CAAS, and part b applies to the audibility function of the CAAS. The proposed change is to both parts; Required Action A.1.5 is identical for both parts. ,

l The CAAS is used to warn plant personnel of a criticality incident or radiation accident. The CAAS does not prevent criticality. The CAAS is designed to detect radiation in the event of a criticality accident and provide an alarm which consists of local horns and lights that serves to alert personnel to move from the work areas potentially affected. The CAAS also alarms at the C-300 Central Control Room. During periods of CAAS inoperability, activities involving uranium enriched to greater than 1 wt % 2"U are limited. Access to the area (s) not covered by criticality accident detection is restricted. Any personnel allowed in the area must be provided with an i alternate means of criticality alarm notification, such as a device that will alarm on sensing a 10 l mr/hr dose rate. In the event that only the audible portion of the alarm is inoperable, USEC i may provide personnel with a radio in constant communication with the Central Control Facility, i USEC has 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> to restore criticality accident detection, which can be accomplished by l installing a portable CAAS.

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9812100106 981207 l PDR ADOCK 07007001 C PDR ,,,

2 DISCUSSION The product withdrawal systems for PGDP are housed in buildings C-310 and C-310A. The facilities in these two buildings provide two complete withdrawal systems that permit simultaneous withdrawal of two product streams with different SU enrichments. One system is l identified as the top product withdrawal system, while the other system is designated the side product withdrawal system. Either system can be used to withdraw material of any assay up to 2

the plant limit of 2.75 wt% 3sU.

UF gas from the diffusion cascade is compressed using Normetex pumps and then cooled to  :

condense the gas to a liquid. Condensing of the gas is through the use of three condensers.

The liquefied UF, flows by gravity into 2.5- or 10-ton product cylinders. Once the cylinder is full, the liquefied UF is routed to one of two accumulators until another empty cylinder is connected to the system or until the withdrawal equipment is shut down. The top withdrawal accumulator .

is of 21,000-lb capacity and the side withdrawal accumulator is of 4,300-lb capacity.

Miscellaneous other equipment supporting the operation includes the R-114 Coolant loop and the supporting Recirculating Cooling Water (RCW) system.

Currently, in the event of CAAS inoperability, TSR 2.3.4.7a and b, Required Action A.1.5 allows completion of the current withdrawal cycle and then discontinuing withdrawal of UF enriched to greater than 1 wt % 5U. Discontinuing withdrawalinvolves isolation of the withdrawal equipment requiring the cascade to be placed in recycle. Although operating parameters can be maintained during recycle, the necessary actions are complex and place the plant in a -

seldom used configuration that poses significant control challenges and increases the likelihood of exceeding assay limits. Therefore, to minimize the impact associated with CAAS inoperability in product withdrawal, USEC proposes to change the TSR to allow additional time for operation of the plant in its normal, steady-state configuration. This would allow the plant to continue withdrawing product after the current cylinder fill cyclo is complete by filling the ,

accumulators as is normally done during a cylinder changeout.

Dependent on the state of operation at the time of CAAS inoperability, the facility could have nc [

cylinder, a full cylinder, or a partially filled cylinder connected to the withdrawal station. The  !

accumulator could be empty, partially filled, or completely full. Therefore, it is possible that even with the proposed TSR change, the plant could be forced into a recycle mode. During normal operations, the accumulators are primarily used during cylinder changeout. The j accumulator inventory resulting from cylinder changeout (usually less than 2000 lbs) is quickly  ;

emptied once liquid flow is reestablished to the new cylinder. The proposed TSR changes would allow the Normetex pumps, condensors, and accumulators to continue operation until the  !

accumulators were full, at which time the cascade would have to be placed in recycle. Filling of the accumulators will typically provide 12 to 13 additional hours before the plant has to be placed in a recycle mode.

Analysis of adequate safety for this amendment request must be based upon the relative magnitude of increased risk associated with extended process operation under known deficient CAAS conditions, along with any compensatory measures taken by the facility to provide some level of radiation detection. According to TSR 2.3.4.7, Action Step B.1.1, restcration of CAAS operability or installation of equivalent CAAS detection must occur within 48 hcurs of the initial i failure. Therefore, this action step provides the upper limit on time available for Roerations l

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during which no accident detection is afforded. Consideration for allowing the plant to continue filling the accumulators once cylinder filling is complete is bounded, then, by 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> (i.e.,

filling of the accumulators buys the full allotted TSR time without the requirement for placing the cascade in recycle). Finally, a determination of comparative risk to plant personnel between the accumulator filling operation under inoperable CAAS conditions versus placing the cascade in recycle should be made.

l Determination of Risk Criticality control for the product withdrawal process is based upon moderation control by 3 maintaining the system within prescribed process parameter limits and by maintaining system integrity. The Safety Analysis Report (SAR) identifies several potential criticality accident  :

scenarios associated with failures in: (1) Normetex pump discharge bellows overpressurization; I (2) corrosion-induced fatigue failures involving the accumulators, Normetex pumps, instrument ,

lines, and UF, cylinder ruptures; and (3) seismic-induced equipment failures resulting in system i integrity breach. In addition, the staff also considers the criticality potential from tornado / extreme wind conditions. Each of these postulated scenarios is discussed below.

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1. Normetex Pump Overpressurization Leading to Criticality The criticality accident scenario of concerre involves a release of uranium within the pump which ,

I could lead to an accumulation of uranium in the pump oil reservoir. The most likely scenario is associated with a potential rupture of the barrier between the process gas and oil / wet air regions of the pump during operatior'.. This condition could occur from an increase in pressure once the accumulators become filled and the pump deadheads against the liquid UF . A rupture on the high pressure side of the pump would allow material to escape from the process J

gas regions of the pump and enter the oil system where UF, would chemically react with the oil to produce UF, and other constituents.

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The theoretical maximum uranium loading is determined to be 75.8 wt% (i.e., the complete conversion of the oilinto UF4 and byproducts). Obviously, it is important to first determine if any uranium loading up to the predicted maximum is capable of reaching a critical state before evaluating the potential risk to plant personnel safety following such a failure. Therefore, the staff performed computer calculations of low enriched uranium concentration in oil as related to the predicted neutron multiplication for uranium loadings approaching the theoretical maximum. Since the oil which is pumped through sealed passages in the spacer column and vanes of the pump is returned to an 80-gallon, self-contained oil reservoir, it is conceivable that I the entire 80-gallon capacity is available to react with a UF, breach. With this assumption, the results are given in Figure 1.

As can be seen, it is possible to reach a critical state if the uranium reaches a loading of approximately 47 wt%, which equates to approximately 1000 lbs of UFe. Although such a {

uranium loading is unlikely due to the drastic change in oil viscosity and increased density which would likely seize the pump well before a critical concentration is reached, a determination of the reliability of controls to preclude a UF, breach will be evaluated for the time of CAAS inoperability to fully undarstand the consequences of this scenario.

. . 4 FIG 1: SENstTIVITY oF URANIUM CONCENTRATION oN REACTIVITY (2 75% Ennched. 60 gallon Otl Capacity. Mmtmal M20 Reflechon) f  !

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r l l 06 i . 4 i-30 35 40 45 60 55 60 65 70 URANIUM LOADING IN OIL (wt%)

The Normetex pumps are equipped with an automatic shutdown system to prevent excessive pump pressures which would result in UF. availability to the lube oil system. This pressure controlis designed as a buffered expansion joint installed between the pump and the block valve on the outlet line. Dual pressure transmitters read the discharge pressure End actuate the pump shutdown circuit prior to system component failure. There is also a UF, release detection system associated with the Normetex pumps. Upon detection of UF., this system trips the pump and shuts the discharge valve, limiting the release to 250 lbs of UFs. Operation of the system is controlled by a TSR. There are no level probes installed on the accumulators and the filling of the accumulators by the Normetex pumps can be completed within the prescribed time allotment of 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, so this system becomes the primary barrier to prevent the UF, breach scenario ,as described above from occurring.

The use of Normetex pumps as primary withdrawal compressors have been in place since  :

about 1987 in C-310, and plant wide, Normetex pumps have operated a total of 274,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />. -

During this time, there have been a number of pump failures and a number of High Discharge Pressure circuitry activations, but none have resulted in a breach of the UF, envelope. From this data, the staff has conservatively estimated the mean time between occurrence for these pumps to be approximately 4089 hours0.0473 days <br />1.136 hours <br />0.00676 weeks <br />0.00156 months <br /> from all causes and 5830 hours0.0675 days <br />1.619 hours <br />0.00964 weeks <br />0.00222 months <br /> between high pressure activations, in other words, the number of automatic pressure sensing circuitry activations is calculated to be 2.04 x 10" occurrences per hour of pump operation. Thus, during the time of CAAS inoperability, the number of upset conditions requiring the activation of the pressure circuitry can be estimated as 9.8 x 10' If the probability of nonfailure of the pressure detection system when called upon is considered for the period of CAAS inoperability, then the probability of a high pressure upset condition resulting in UF, contacting the pump oil is approximately 8.07 x 10~5 The staff considers probabilities on the order of once every 100,000 years to be highly unlikely. Thus, the staff finds that this scenario does not pose undue risk during the time of CAAS inoperability.

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2. Corrosion-induced Fatigue Failures Leadi,g to Criticality The criticality accident scenarios of concern for corrosion-induced fatigue failures allinvolve a i large release of uranium to the atmosphere that hygroscopically absorbs enough moisture and deposits in a location such that a critical configuration is reached. Although the SAR lists i potential criticality scenarios involving fatigue failures for many different components of the withdrawal process, the staff has determined that fatigue failures in the accumulators and UF, fill cylinders are the most severe and bound the other postulated failures. Although filling the accumulators is the new activity that is proposed, the staff has also included an evaluation on the UF, cylinders for completeness.

Accumulators - The top withdrawal accumulator is of 21,000-lb capacity and the side withdrawal accumulator is of 4,300-Ib capacity. Thickness measurements are taken on these components at least every five years in order to establish corrosion rates, determine estimated remaining life, and verify the vessel wall has not been reduced below minimum-required metal thicknesses per the current version of the National Boiler inspection Code. Reference 2 indicates that thicknesses have not decreased significantly and demonstrate that the thicknesses are well above the minimum requirements. Nevertheless,if a corrosion-induced fatigue failure were to occur, the system integrity breach would cause the UF, present to be released to the atmosphere due to the operating pressures of the withdrawal process and thus, the most severe release would be an entire draining of the 21,000-lb capacity accumulator.

The accumulators are housed on the ground floor of the C-310A building. This building is attached to and located immediately north of C-310. Although no dimensions are given in the SAR as to the volumetric capacity of building C-310A, the staff made a conservative estimate based upon a similar facility at the Portsmouth Gaseous Diffusion Plant to determino the volume of moist air available to react with the released UF, liquid. Although the relative humidity in this region of the country averages above 80%, building-specific conditions are not expected to get above about 60% And, building ternperatures are considered to range from 60 to 100 degrees Fahrenheit. Thus, with these assumptions, it is only possible for the UO2F, to reach a hydration level equivalent to about an H:U ratio of 4. However, NRC staff calculations conservatively indicate that, at most,300 lbs of water is available to react with the UF, and can only produce a relatively small quantity of UO2F, (2564.8 lbs) if all the availabic moisture were used in the conversion reaction producing essr;ntially anhydrous UO2 F,. Anhydrous UO2 F2 is subcritical at all quantities and even at an H:V ratio of 2 more than 4400 lbs of UO2 F 2 in a spherical form would be required to reach a critical state. Thus, a critical configuration would not be possible no matter what geometric shape the material assumed in reality, the material ,

would form a thin deposit more or less unibrmly distributed over a wide area. Such a ,

geometric distribution would be extremely subcritical.

UF, Fill Cylinders - A cylinder release failure could occur by three mechanisms: (1) a cylinder valve failure; (2) a passive structural failure; or (3) a passive pigtail failure in which the pigtail isolation system is unable to close the cylinder safety valve. Because operating methods and quality controllimits exist governing the inspection and certification of cylinders and cylinder valves, the probability of a cylinder or valve failing from corrosion-induced fatigue is low.  ;

Nevertheless, the maximum release potential for all three cases involves the release of the

, contents of a full 10-ton cylinder (20,000 lbs of UF ).

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6 However, as was previously demonstrated, the volume of moist air available for reaction is not sufficient to react all of the 20,000 lbs of UFe that would be present. The remainder of the unreacted UF, would initially settle out and could potentially settle in a scale pit. However, a characteristic of low-enriched uranium is that enrichments less than about 5.6% 23sU can not be made criticalin the absence of moderator. Therefore, such a condition would remain subcritical for an extended period of time. Although it can be postulated that over time additional moist air could seep into building C-310 to further react the remaining UF, and eventually reach a critical state, the time for this to occur would be considerable and the hazardous properties of the HF gas byproduct would be self-protecting in keeping personnel safely away from the accident site.

Therefore, the staff concludes that a passive UF cylinder breach would not pose a hazardous i nuclear criticality safety (NCS) condition during the time of CAAS inoperability.

3. Seismic-induced Equipment Failures Leading to Criticality l

According to the Application SAR, an Evaluation Base Earthquake (EBE) would result in no major damage to the process structures or to associated equipment or facilities that will impact safety for on-site or off-site personnel. Specifically, for the C-310 facility, the estimated UF, release would be at most 720 lbs. However, recent information reported to the NRC by letter dated February 20,1998 indicates that USEC determined that conservative assumptions may not have been utilized in the SAR Upgrade accident analysis and, as a result, the potential consequences of postulated seismically-induced failures in the liquid withdrawal facilities could be increased over those previously reported. USEC also concluded that the consequences of postulated seismic failures could be more severe than currently reported in Chapter 4 of the Application SAR. In doing the SAR Upgrade, USEC determined that the process piping, condensers, and accumulators could fail at a 0.05 g earthquake. On September 30,1998, USEC completed modifications to the equipment such that it will withstand a 0.165 g earthquake.

Although one could postulate that such an event would be bounded by corrosion-induced failures in this equipment as described above, the staff notes that such conclusions may be inaccurate, in that, an unlimited source of moist air is likely to be available following such an event. ' Water systems are not designed for seismic loads and could present a ready moderator if they failed. The size of the process buildings, the leakage area between floors, and the barriers between the UF, and the fire suppression systems make criticality a remote possibility unless building collapse occurs. In the event of a complete building collapse, significant quantities of water from the RCW and fire suppression systems would be available for mixing with the UF into a fissile solution and accumulating in unfavorable geometries.

The effects associated with a seismically-induced criticality would pertain to individuals in the immediate area. Until the equipment modifications are complete, building access is limited to necessary personnel. In addition individuals would be required to have an alternate means of l

criticality alarm notification. The event itself also acts as an alarm to personnel. The see and flee policy requires personnel to immediately evacuate the area of a toxic material release.

Only rescue or emergency response personnel would be expected to enter an area after a significant UF, release. Emergency procedures require that appropriate conditions be established for reentry to an evacuated facility. A consideration for criticality potential would be more appropriately analyzed at that time by emergency and plant NCS staff as actual conditions and release amounts would be better quantified. Entering personnel would be made t

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aware of a criticality due to hand held instrumentation. Thus, although e seismic event potentially represents a possibility of criticality, the staff finds that this condition would not pose an unreasonable NCS condition during the time of CAAS inoperability and immediately l following a seismic event.

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4. Tornado / Extreme Wind Effects Leading to Criticality According to the SAR, the probability of accident scenarios involving hazards to on- and off-site l personnel resulting from tornadoes and/or extreme winds is predicted to be extremely low. This

, conclusion is based upon the low probabilities of occurrence of the type of windspeeds l necessary to cause sufficient damage to rupture the UF withdrawal process with subsequent UF, release.

For UF, to be released during a tornado or extreme wind event, the wind force must have a  ;

velocity strong enough to cause structural steel framing failure. This failure would  !

produce / generate missiles that could cause a loss of containment of the liquid UF . However,  !

the windspeed associated with such structural failure and the probability of exceeding this i speed in any given year is 170 mph and less than 1 in 50,000 years, respectively. Even if such

' l a condition were to occur, the staff concludes that such failures would be clearly bounded by the accident scenarios associated with a seismic event as described above. Therefore, the staff finds that this condition would not pose a hazardous NCS condition during the time of CAAS inoperability.

Qualitative Comoarative Risk Determination Since criticality alarm systems do not protect against the health hazards of an initial NCS event but rather mitigate the consequences to the larger plant population following an unexpected critical excursion, it is worthwhile to discuss the comparative risks of operating the withdrawal system under deficient CAAS conditions versus placing the cascade in recycle. As was previously discussed, operation of the withdrawal system is a highly automated process with several defense-in-depth safety systems and alarms. It requires little hurnan intervention even I during postulated process upset conditions. On the other hand, operation of the cascade in recycle requires much more human interaction, and although such a system would have 1 operable CAAS coverage, such human operations increase the likelihood of maloperation for l such a rarely used configuration.

For instance, operation in recycle will cause the assay in the top cells to increase. In order to l control the assay in these cells, several options are available and include diverting product from the top of the cascade to surge drums, diversion of the product stream to a lower point in the cascade to mix assays, or diverting a lower assay stream such as the Bottom Overlap or feed material to the top of the cascade to downblend the assay. As these actions are taken to control the assay in the top cascade, the assay in other portions of the cascade will tend to increase. Due to this being an infrequently performed process, the probability of operator errors in valving operations is likely to increase over normal operating conditions. Additionally, l

the recycle operation involves complications in controlling assay and light and intermediate gas accumulations. Putting the plant in recycle is an abnormal operation that could cause l unanticipated transients and pressure surges in the cascade that may actually increase the probability of other plant events, e.g., UF bot-metal reactions and/or compressor deblading.

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l Thus, the staff qualitatively concludes that operation of the withdrawal process in a steady-state mode under deficient CAAS conditions poses less risk to plant personnel safety than does operatipn in an unfamiliar mode and one that requires heightened awareness and careful attention for successful operation. The qualitative conclusion of lower risk assumes that other  :

i activities involving uranium enriched to greater than 1 wt % *U are discontinued in accordance with the TSRs, the UFerelease detection and isolation systems are operable as required by the TSRs, and the operation is stopped upon loss of the NCS parameter controls for the operation.

ENVIRONMENTAL REVIEW lssuance of an amendment to Certificate of Compliance GDP-1 to revise the TSR to provide additional time to operate the withdrawal station in normal steady state operation upon CAAS inoperability is subject to the categorical exclusion provided in 10 CFR 51.22(cV19). Therefore, neither an environmental assessment nor an environmental impact statemen required for the proposed action.

CONCLUSION The staff concludes that the proposed revision to TSR 2.3.4.7 to allow the accumulators to be filled when the CAAS is inoperable poses less risk to plant personnel safety than does operation in the recycle mode. The postulated events discussed above are considered unlikely to occur during the limited period of CAAS inoperability. The staff recommends that the revised TSR be approved.

The Operations Branch and the Region ill Inspection staffs have no objection to this proposed action.

Principal Contributors Jack Davis Merri Horn DISTRIBUTION:(Control No. 320S)

Docket 70-7001 NRC File Center PUBLIC Rill KO'Brien, Rill NMSSr# NMSS dir. ofc. rM FCSSrM FCOB SPBrn PHiland.

Rlli

• See previous concurrence OFC *SPB *SPB *SPB *SPB 'SPB I

NAME MHorn:ij JDavis DHoadley MGalloway RPierson DATE 10/8/98 10/19/98 10/08/98 11/25/98 11/25 /98 I C = COVER . E = COVER & ENCLOSURE N = NO COPY  !

OFFICIAL RECORD COPY l l

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%hus, the staff qualitatively concludes that operation of the withdrawal process in a steady-state made under deficient CAAS conditions poses less risk to plant personnel safety than does ,

ope ion in an unfamiliar mode and one that requires heightened awareness and careful  !

attenti for successful operation. The qualitative conclusion of lower risk assumes that other activities olving uranium enriched to greater than 1 wt % "U are discontinued in accordance

with the TS the UF' release detection and isolation systems are operable as required by the l TSRS, and the eration is stopped upon loss of the NCS parameter controls for the operation.

! ENVIRONMENTAL VIEW l

j y

issuance of an amendment o Certificate of Compliance GDP-1 to revise the TSR to provide

additional time to operate the ithdrawal station in normal steady state operation upon CAAS

1. inoperability is subject to the ca orical exclusion provided in 10 CFR 51.22(c)(19). Therefore, neither an environmental assessm t nor an environmental impact staternent is required for the proposed action.

CONCLUSION l l

The staff concludes that the proposed revision e TSR 2.3.4.7 to allow the accumulators to be filled when the CAAS is inoperable poses less ris plant personnel safety than does operation in the recycle mode. The postulated even discussed above are considered unlikely to occur during the limited period of CAAS inoperability. he staff recommends that the revised TSR be approved.

The Operations Branch and the Region lli inspection staffs hav o objection to this proposed action.

Princioal Contributors Jack Davis Merri Horn DISTRIBUTION:(Control No. 320S) l Docket 70 7001 NRC File Center PUBLIC Rlli KO'Brien, Rill  !

NMSSrM NMSS dir. ofc. rM FCSSrM FCOB SPBrM PHiland, i Rile )

• See previous concurrence  !

C FC 'SPB 'SPB 'SPB SPB i h SPB C NAME MHorn:ij JDavis DHoadley

/

ay n'

DATE 10/8/98 10/19/98 10/08/98 fl /@98 il /JdB I C = COVER E = COVER & ENCLOSURE N a NO COPY OFFICIAL RECORD COPY l

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a ention for successful operation. It is also noted that the Department of Energy allowed  ;

op ation of the accumulators during periods of CAAS inoperability.

ENVIR NMENTAL REVIEW lssuance o n amendment to Certificate of Compliance GDP-1 to revise the TSR to provide additional tim to operate the withdrawal station in normal steady state operation upon CAAS inoperability is s ject to the categorical exclusion provided in 10 CFR 51.22(c)(19). Therefore, neither an environ ental assessment nor an environmental impact statement is required for the proposed action. .

CONCLUSION The staff concludes that the pro sed revision to TSR 2.3.4.7 to allow the accumulators to be filled when the CAAS is inoperable oses less risk to plant personnel safety than does operation l in the recycle mode. The postulated nts discussed above are considered unlikely to occur  !

during the limited period of CAAS inoper ility. The staff recommends that the revised TSR be I approved. l The Operations Branch and the Region ill Inspect, staffs have no objection to this proposed action.

l Erincioal Contributors Jack Davis Merri Horn DISTRIBUTION: (Control No. 320S)

Docket 70-7001 NRC File Center PUBLIC Rlli KO'Brien. Rill NMSS r# NMSS dir. ofc. r# FCSS r# FCOB SPB r# ~ nd, Rill OFC SPB FCOB b VPB h SPB SPB NAME MNo ij JDavis Headley MGalloway RPierson DATE /0 / f/98 d th/98 k/98 / /98 //98 C = COVER E = COVER & ENCLOSURE N = NO COPY j OFFICIAL RECORD COPY '

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