ML20206P318

Submits Responses to NRC 970828,0927 & 1023 Requests for Addl Info on Cushing Site Decommissioning Plan.Revised Portion of Section 3 of Subj Plan Encl

ML20206P318
Person / Time
Site:	07003073
Issue date:	11/26/1997
From:	Lux J KERR-MCGEE CORP.
To:	Brown S NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
References
NUDOCS 9901110174
Download: ML20206P318 (16)

Text

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sem wmouema wnes November 26,1997 Mr. Stewart Brown Iow-level Waste & Decommissioning Projects Branch Division of Waste Management Office of NuclearMaterials Safety & Safeguards S. Nuclear Regulatory Commission Washington,D. C. 20555 Re:

DocketNo.70 3073 Ilcense No. SNM-1999

Dear Mr. Brown:

Kerr-McGee Corporation (KMC) submits the attached portion of Section 3 of the Cushing Site Decommissioning Plan (SDP) as a license amendment request. KMC received NRC's comments on revised Sections 3.2 (Criteria) submitted August 28,19)/, and 3.3.1 (Pit 4), submitted September 27,1997. NRC requested that KMC submit the criteria and the decommissioning process proposed for Pit 4 together because of concems about approving criteria not needed for the Pit 4 effort. This revised portion of Section 3 of the SDP combines the criteria for decomrmssioning Pit 4 along with the proposed process. This revision therefore replaces the submittals referenced above. The following are KMC's responses to NRC's comments, dated October 23,1997.

General C-ts GeneralCommenti Review ofSection 3.2 will be performed in the context ofthe complete DPlan review and not as part of a specific Pit 4 review. Therefore, ifKerr-McGee believes that approval ofthese criteria are needed in order to remediate Pit 4, Kerr-McGee should submit the specific criteria aspart of a Section 3.3.1 revisedsubmittal.

KMCResponse

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The criteria needed to decommission Pit 4 now appear within the revised Section 3.3.1 submittal.

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The August 28,1997 submbal is hereby withdrawn. A revised Site Decommissioning Plan, contaming within Section 3.2 all the criteria required fc,r decommissioning the site, will be submitted presently.

g General Comment 2

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Requestsfor approval ofportion}s ofthe DPlan, such as Section 3.3.1, license amendment request. Kerr-McGee should submit a request to amend its license.

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KNfd Resnonse This revised Section 3.3.1 is submitted in the form of a license amendment request.

General Comment 3 Provide or reference programs under which Pit 4 will be remediated that ensure public health and safety, such as a Radiation Protection and Quality Assurance Programs.

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l KMC Response l

Section 3.3.1.4 of the attached submittal states that all decommissioning activities will be l

performed in accordance with the site specific Radiation Safety Plan developed by qualified Health l

Physics personnel to ensure compliance with 10 CFR Part 20. Section 3.3.1.5 commits to the l

perforrnanem of all work in accordance with the Quality Assurance requuements of ASME's NQA-l 1, as well as the ANSI /ASQC ISO 9001 standard. F JREG/CR-5849, which provides guidance for final survey activities, references NQA-1. The commitment to comply with the above-referenced standards fulfills the quality assurance requi'ements of NUREG/CR-5849.

General Comment 4 Additionalinformatior. is needed before the review ofSection 3.3.1 can be completed. The staf's comments are enclosed.

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Spec $c Comment 1 Describe the procedures and QAfQCprogram that will ensure the Pit 4 remediation plan is implemented as written, and that reported data is ofsuficient quality and validated.

l KMC Response l

h Oklahoma Department of Environmental Quality appmved a Phase III Remedial Design that l

govems the non-radiological aspects of remediating the acid hydrocarbon sludges contained in Pits 1 through 5. Special Work Permits and/or Radiation Safety Procedures will be developed to direct radiological work, such as surveys performed to sort neutralized waste, retroval, transportation, and placement of contaminated waste in the Radioactive Materials Storage Area, exit surveys for personnel and equipment from RMA-3 (which contains Pit 4), etc. The site-specific QA/QC program will comply with the NQA-1 and ISO 9001 standards for quality assurance h existing quality system is currently being revised to address the projected scope of decommissioning activities prior to NRC approval to perform those activitics. As stated above, radiation protection and quality assurance are specifically addressed in Sections 3.3.1.4 and 3.3.1.5 of the enclosed submittal.

Snecific Comment 2 l

Zones 1 and 2 Decommissioning Activities, Item 8-Expand the discussion of this section to address thefollowing: (1) uranium contamination. (2) e2pasure rate measurements, (3) samples to be taken at elevated xan points, and (4) action levelsfor samplingfrom elevated scan points.

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Item 8 addressed the final survey of stabilized waste after placement in the disposal cell. KMC split

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Zone 1 and 2 decommissioning and final survey activities (which were addressed in one section in Pit 4 Subadual Page 2 i

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thei Sa'p*W 27 submittal) into two separate sections of this submittal, for purposes of j

clarification. The discussion requested is now contained in Items 2 - 5 of 7ones I and 2 Final j

Survey Activities.

1) Samples will be analyzed for Th-232, U-238, U-235, and Ra-226. 2) Exposure rate measurements will be collected at each five-meter grid point. 3) Areas for which scan values indicate Option 1 limits may be exceeded will be sampled to delineate the area of elevated activity.

4) Action levels will be set based on the instrument used. If the same instrument configuration used to sort neutralized waste is used for final survey, the action level will be the same as for Pit 4 h-= =issicaing If a different instrument configuration is used, the action level will be adjusted accordingly.

Soecdc Comment 3 Zones 1 and 2 Decommissioning Activities, Jtem 10 - Will there be scan swveys ofPit 4 excavated swfaces once the radioactive material has been (removed)?

KMC Response Items 6 - 9 of Zone 1 and 2 Final Survey Activities describe the final survey that will be performed in the Pit 4 area after all excavation is fmished. 100% of the esea will be scanned, and samples will be collected and exposure rate readmgs recorded on a five meter grid. As in the landfill, locations yielding scan readings indicating the possible presence of material exceeding the Option 1 limit will be sampled to delineate the area of clevated activity.

Soecific Comment 4 Zones 1 and 2 Decommissioning Activities - Describe the statistical treaonent that will be applied to the data obtainedfrom these areas.

KMC Response Application of radioactivity limits to measurement areas is discussed in Section 3.3.1.2. 'Ibe description of final survey activities, now presented in Zones 1 and 2 Final Survey Activities, has also been expanded. The maximum value and average activity for each survey unit and the arra weighted average activity for areas of elevated activity will be calculated. For each survey unit and area of elevated activity, en=pli=* with the criteria for volumetric activity will be demonstrated at the 95% confidence level via a t-test. Since, u criteria for exposure rate is applied to each measurement, statistical treaunent on'lis data is tmnecessary.

Soecific Comment S Zone 3 Decommissioning Activities - Describe the statistical treatment that will be applied to the da:.2 obtainedfrom this area.

E M G annensa During a confemace call with NRC this comment was clarified to request statisticaljustification for the reduced sampling frequency proposed. The maximum thorium activity in 155 samples is several standard deviations below the limit, so there is greater than a 95% probability that the limit will not be exceeded. On this basis, KMC couldjustify proposing not to sample Zone 3. However, scanning will continue to be 1.erformed in the pit after neutralintion, and final survey at a reduced Pit 4 Submittal Page 3

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frequency will still be performed to further reduce the potential to inadvertently place material l

exceedmg the decommissioning criteria in the disposal cell. The discussion of Zone 3 decommissioning activities has been expanded to describe the rationale for reducing the sampling

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frequencyin Zone 3.

i Soecific Conenent 6

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" Field Action Levels " - Include an action levelfor uranium.

i KMC Response The field action level for the **nning instrument is based on the analysis of samples from Zone 2, which includes analysis for uranium, thorium, and radium. The field action level is not nuclide specific. Because the activity of uranium has been shown to be consistently far below Option 1

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limits in Pit 4, there is no reason to develop a uranium-based field action level.

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Specific Comment 7 l

Provide thefaal compliance criteriafor the on-site cell.

pr KMC Response The criteria stipulated in Section 3.3.1.2 apply both to the excavated area after removal of Pit 4 waste, and to the on site disposal cell into which treated waste will be placed. Material exceedmg these criteria will be placed in the radioactive materials storage area for subsequent shipment to a licensed disposal site.

NondadiolomicalImnacts In telephone conversations subsequent to NRC's October,1997 comments, NRC requested information about non-radiological impacts for inclusion in t eir environmental assessment. It is h

imps.it to note that non-radiological hazards gg being add'.essed by the Oklahoma Department of Environmental Quality's (DEQ's) through their oversight of site remediation. The following information summary is provided for NRC's environmental ~ assessment.

The acid sludge rernediation process is capable of generating wee types of emissions:

1. Dust,

2. SO, and 2

3. Petroleum hydrocarbon compounds.

Dust can be generated when reagent is applied to the surface of t'1e waste pits for use in in-situ neutralintion and when reagent dust is pneumatically loaded into silos located at the treatment plant. SO is released when the neutralization reagent is mixed into the waste. DEQ has stipulated 2

limits for dust (PM 10) and SO emissions that are lower than National Ambient Air Quality 2

. Standards (NAAQS) to ensure that NAAQS will not 'oe exceeded. In the process of neutrahzing over 180,000 cubic yards of waste in Pit 5, the NAAQS have not been exceeded even once.

Petroleum hy&wJwe vapors are also released during the neutralization process. The primary hazard is offensive odor. No idaar&d hazardous volatile organic compounds are present in detecable concentrations. KMC has not yet identified individual constituents present in sufficient concentrations to measure the impact. DEQ is Inonitoring KMC's efforts to control the emission of Pit 4 Submittal Page 4

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petroleurn hydrocarbons. Should individual constituents be fournd in concenuations justifying

. additional controls, KMC will hnplernent whatever controls are necessary to protect public health.

j If you have any questions or comments, please call me at (405) 270-2694.

l Sincerely, l

l JeffLux Prop

• Manager l

C. L Cain,NRC Region IV i

Rick Reiley,OMWg Citizens' Oversight Committee Gene Smith, ODEQ Darrell Shults,ODEQ l

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3.3 CLEANUP CANDIDATES AND TASKS Uranium and thorium contaminated materials requiring decommissioning remain

. in certain areas of the Cushing site. The status and planned decommissioning activities for these areas are summarized hereafter.-

3,3.1 RMA-3 3.3.1.1 Acid Sludos Pit 4 Pit 4 contains acidic hydrocatt>on sludge from a lubricating oil manufacturing operation. The waste is primarily heavy hydrocarbon containing sulfuric acid (typically 15 to 25 percent). The northwest comer of the pit contains thorium contaminated material.

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In 1990, the pit was cored, and sampled to delineate the extent of radioactive i

contamination.

Subsurface samples were collected from ten random and ten j

systematic borings. Systematic borings were drilled in the northwest portion of the pit where previous data had indicated elevated concentrations of radionuclides.

i Uranium is present in low coricentrations throughout the pit. The average concentration was 1.2 pCi/g, with a maximum of 7.4 pCi/g (less than 25% of the Option l

1 limit). Thorium was found to be present in concentrations above the Option 1 limit i

only in the northwest portion of the pit. The concentration of thorium in the various j

zones is discussed below.

KMC has divided Pit 4 into the three zones (Figure 3.1) based on thorium content.

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. Zone 1 - Samples of acidic hydrocarbon sludge from Zone 1 contain the highest concentrations of thorium detected in Pit 4.

The average and maximum thorium concentrations detected in Zone 1 were 9.0 and 34 pCi/g, respectively. Most i

of the waste in Zone i may exceed the Option 1 limit for thorium after neutralization and be shipped off site for disposal.

. Zone 2 - Samples of acidic hydrocarbon sludge from Zone 2 contain thorium in lower concentrations than found in Zone 1. The average and maximum thorium j

concentrations detected in Zone 2 were 2.6 and 12.2 pCl/g, respectively. The waste h Zone 2 may or may not exceed the Option i limit after neutralization.

. Zone 3 - Samples of acidic hydrocarbon sludge in Zone 3 contain thorium in concentrations well below the Option 1 limit. The average and maximum thorium concentrations detected in Zone 3 were 0.7 and 2.8 pC1/g, respectively. Most of the j '

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waste in Zone 3 will be below the Option 1 limit after neutratzation and will be disposed of in the onsite disposal cell.

l An estimated 9,000 cubic yards of acidic hydrocarbon sludge in Pit 4 exceeds the decommissioning criteria.

3.3.1.2 PaWical Criteria for Pit 4 Decommissionina KMC proposes to judge completion of Pit 4 decommissioning on the criteria presented below. The proposed criteria are based on existing NRC guidance.

Exposure Rate Umit I

The gamma exposure rate cannot exceed 10 pR/hr above background at 1 meter above the ground.

Volumetnc Limit Option 1 limits from the BTP provides for unrestricted release of land that contains uranium and/or thorium in concentrations less than the limits shown in Table 3.1.

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Thorium (Th***)

5 Depleted Uranium 35 Enriched Uranium 30 a) anoa me<*emund Laboratory analytical methods are incapable of distinguisNng depleted U23e from 1

enriched U2se. At concentrations near background, such as in Pit 4, it is only practical i 34 'l l

to analyze soil for the concentrations of Um and U2se._ As a conservative rneasure to satisfy NRC's concem that some U23e may have come from enriched uranium, KMC will

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consider 30 pCi/g the Option 1 limit for all uranium isotopes. Material therefore meets Option 1 limhs when the combined radionuclide concentration meets the following j

equation:

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30 10 where [ ] is not concentraticn in pCi/g.

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' Concentration limits for thorium and natural uranium wastes containing fewer daughters than at secular equilibrium may be calculated on a case-by-case basis using isotopic data that are applicable.

Surface Contamination Limit The maximum radioactive contamination on surfaces which may be released without restriction is stated in Table 3.2. Uranium and thorium were received in refined form without significant decay products. While thorium progeny will have grown near to radioactive equilibrium, neither uranium nor thorium progeny will exceed its parent's concentration. Thus, the limits tabulated are appropriate for uranium, thorium, and their associated decay products. In.he event mixed uranium and thorium are present, the sum-of fractions s 1 formula may be used to derive an appropriate limit based on these values.

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~ ' ACCEPTABLE SURFACE CONTAMIN' TION LEVEL 8.. [

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[Nuclides * ~ 1, PAverage h* '

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(dpm/100 cm2)

(dpm/100 cm y1 a

Uranium 5,000 15,000 1,000 asa Thorium 1000 3000 200 a) Where surface contaminsbon by botti alpha and beta-gm.ma-omitbng nuendes exists, the Amrts estab!shed for alpFa-and bete-gamma-emitting nuclides sNndd apply independertty.

D) As used in fils tatne, dpm (11sintegrations per minute) meane the rate of emission oy red oectW material as determeed by j

ccrreding the counts per mnute observed by an appropriate detector for background, efRciency, and geometne factos assometed with the instrumentation.

2 c) Measuretrants of everage contarrinant should not be awreged over more than 1 m. For objects of less surfem area the everage should be demed for each olyct.

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d) The mammum contaminsbon levelfpplies to an area of not rnore than 100 cm,

2 The amourt of removabia radioedtve material per 100 an of surface area shouta be determined by wiping that area with e) dry finer or so't absorbent paper, appfying moderste prosaure, and essessing tne amount of radioactive material on the wpe with an appropriate insnnent of known efRciency. When removabW contaminetson on ot@ cts ofless sJrface ela is determined, the po'1hent levels shoidd be reduced proportenaRy sM the entre surface should be wiped.

Aeolication of Radioactivity Limits to Measurement Area Average Radioactivity Stalc) radioactivity limits are for average values, above background, applicable a

to affected areas:

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@ 010 11/24/97 100 m2 area for soil radioactivity, i

100 m2 area for exposure rate on open land, and 100 m2 area for paved surface radioactivity.

Area-weightedRadioactivRy The average radioactivity concentration in soil must be < (100/A)1/2 times the stated limit, where A is the area of elevated radioactivity in m2 The maximum area forwhich this applies is 100 m2, Surface radioactivity on a paved surface out-of-doors that is between one and three' times the stated limit is acceptable provided the area-weighted average radioactivity within a 100 m2 area containing the elevated activity is less than the stateo limit.

Maximum Radoactivity The maximum radioactivity in soil at any location may not exceed three times the stated limit above background.

The maximum exposure rate at any location indoors or out-of doors may not

- exceed two times the stated limit above background.

For the purposes of this plan the Option 1 limit refers to the sum of the fraction result for an individual sample. The term criteria refers to the area weighted result of a group of samples.

3 3.1.3 Pit 4 Decommisa%ina Activities Experience treating acidic hydrocarbon sludge in similar pits has shown that excavation without prior neutralization, generates sulfur dioxide emissions that exceed National Ambient Air Quality Standards at the property line. In addition, the sludge is very corrosive to equipment and dangerous to workers if reot first neutralized.

Therefore, the sulfuric acid contained in the addic hydrocarbon sludge requires j

neutralization prior to excavation.

Neutralized material that contains radionuclides in excess of Option 1 limits will be identified while still in Pit 4, excavated, and transported to a specially constructed radioactive meterials storage area (section 3.4.4) for temporary storage prior to offstte disposal. Neutralized material that contains radionuclides in concentrations below the Option 1 limit will be excavated, treated and dispeaed of in accordance with a remedustion plan approved by the Oklahoma Department of Environmental Quality cuermo sne o comaswanine pien 4

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(DEQ). Details of the planned decommissioning c, Pit 4 are provided in the following j

sections.

j Zones 1 and 2 Decommissionina Activities i

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1. A 50x50 foot grid referenced to the site-wide grid will be established on the i

surface of the pit.

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2. A layer of reagent (agricultural lime) will be placed over each grid block.

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3. The acidic sludge in each block will be neutralized to a pH of approximately 5 or 6 by adding and mixing in reagent to depth. The mixing process produces a relatively homogeneous material with depth.

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4. in-situ neutralized material will be surface scanned in 18-inch lifts with a Nel j

detector to locate material that exceeds Option 1 limits. Scans will be performed on grid lines spaced at 8-foot intervals, generating at least 50 i

data points in each 50x50 grid (Figure 3.2). KMC will determine the bias 1

and 95% confidence interval of the scanning instrument ano set field action I

levels (discussed below) prior to initiating excavation of neutralized material.

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5. Neutralized maledal which exceeds Option 1 limits will be excavated in 18-inch lifts and transported to the radioactive materials storage area (RMSA) i (section 3.4.4). Once approved for disposal, the material will be packaged and transported to a permitted off-site dispxmal facility.

6. Neutralized material which meets Option 1 limits will be excavated in 18-inch lifts, stabilized by blending in cement kiln dust or similar reagent, and transported to the onsite Other Industrial Waste (OlW) disposal cell.

Field Action Levels Experience at other KMC, sites has shown that scanning can be used to sort materials prior to excavation and disposal. KMC plans to scan in-situ neutralized material to determine whether the material meets the Option i limit. Prior to sorting and excavating, KMC will evaluate the correlation of the scan reading with the average radionuclide concentration of an 18-inch lift of neutralized material. The evaluation will be conducted on neutralized material in a 50-foot by 50-foot block located in Zone 2 where ti.e thorium concentration in tested materials will be near the Option 1 limit.

KMC will select a minimum of twenty locations on the surface of the test block to survey and cellect samples. Twenty 18-inch cores will be obtained from the random locations in the scanned block. Three samples (0-6",6-12", and 12-18") from each core will be analyzed in the on-site gamma spectrum analyzer.

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'The three analytical results will be averaged to represent the thorium concentration at each core location. KMC will calculate the difference between the l

average thorium concentration and the scan result. KMC will calculate the mean and

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standard deviation of the differences to describe the bias of the scanning instrument.

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The bias and the standard deviation of the scanning instrument will be used to i

set field acbon levels for sorting neutralized material. KMC will set the action levels j

such that, at a g5% level of confidence, neutralized material transported to the on-site disposal cell will contain thorium in concentrations below the Option 1 limit. The j

effectiveness of the scanning instrument in identifying materials contaminated in excess l

of Option 1 iimits will also be verified in the disposal cell by scanning and sampling.

l Zones 1 and 2 Final Survev Activities Stabilized Pit 4 material that is transported to the OlW disposal cell will be final

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surveyed as detailed below.

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1. In the disposal cell the stabilized material will be placed in 8-inch lifts and compacted to approximately 6-inches.

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2. Each 6-inch layer of stabilized material from Zones 1 and 2 placed in the l

disposal cell will be surveyed by scanning 100% of the area, collecting samples on a five meter grid (Figure 3.2), and recording exposure rate j

measurements at each 5-meter grid location. Samples will be analyzed by l

the on-site 'Jamma spectrometer for U-238, U-235, Th-232, and Ra-226. U-i 234 activ;ty will be calculated based on U-238 and U-235 values.

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3. Additional sampling will be conducted to delineate the area of elevated j

actnnty if scanning and/or sampling results indicate that material exceeding i

the Optior.1 limits is present.

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4. Analytical results from the sampling specified above will be used to i

calculate the average and maximum activity of the survey unit, and the l

area-weighted average activity of areas of elevated activity. A stabstical i

test such as a t-test will be used to demonstrate that criteria have been achieved at the 95% confidence level.

5. If survey and/or sampling results indicate that material exceeding the criteria specified Section 3.3.1.2 has been placed in the disposal cell, the material will be excavated and transported to the RMSA pending offsite disposal.

6. KMC will final survey Pit 4 after excavation of the neutralized sludge to verify that residual soils do not exceed the criteria. The area will be surveyed by scanning 100% of the area, collecting samples on a five meter C.iersig site Dommmiseloning Pan 6

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g' rid (Figure 3.2), and recording exposure rate measurements at each 5-meter grid location. Samples will be analyzed by the on site gamma I

spectrometer for U-238, U-235. Th-232, and Ra-226. U-234 activity will be calculated based on U-238 and U-235 values, i

7. Additional sampling will be conducted to delineate the area of elevated activity if scanning and/or sampling results indicate that material exceeding the Option 1 limits is present.

8. Analytical results from the sampling specified above will be used to calculate the average and maximum activity of the survey unit, and the area-weighted average activity of areas of elevated activity. A statistical l

test such as a t-test will be used to demonstrate that criteria have been achieved at the 95% confidence level.

9. If survey and/or sampling results indicate that material exceeding the criteria specified Section 3.3.1.2 remains, the material will be excavated and transported to the RMSA pending offsite de,posal.

10. KMC will provide NRC an opportunity to perform a confirmatory survey prior to placing clean soil in the excavated area.

11. KMC will partially backfill Pit 4 with matenal obtained from Unaffected Area l

3, or other "cisan" material. All material used for backfill will comply with the decommissioning criteria.

Zone 3 Decommissionina Activities During the 1990 characterization of Pit 4, KMC drilled thirteen boreholes and collected 155 indrvidual samples from Zone 3. The highest thorium concentration observed in these 155 samples was 2.8 pCl/g. The average thorium concentration of j

these samples was 0.73 pCilg with a standard deviation of 0.8 pCilg. Since no sample exceeded the proposed limit and the average thorium concentration is more than 5 standard deviations below the proposed limit, it is highly unlikely that there is materfsl in Zone 3 that exceeds Option 1 criteria.

Decommisaloning activities will therefore be similar to those described for Zones 1 and 2, with a reduced frequency of scanning and sample collection. The same field action le /el will be used for Zone 3 as for Zones 1 and 2. However, scanning of the in-l situ neutralized materials in Zone 3 will be conducted on lines spaced 16 feet apart 1

instead of along lines 8 feet spart as was specified for Zones 1 and 2.

Figure 3.2 l

shows the scanning lines for IM 4 in all three zones, as well as sample location and I

scanning lines for the dispensi cell. Sample locations and scanning lines for the excavated Pit 4 area will be the same as shown for Zones 1 and 2 in the disposal cell.

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11/24/97 Zone 3 Final' Survey Activities Stabilized Pit 4 material that is transported to the OlW disposal cell will be final surveyed as detailed below.

1. In the disposal cell the stabilized material will be placed in 8-inch lifts and compacted to approx' ately 6-inches.

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2. Each 6-inch layer of stabilized material from Zones 1 and 2 placed in the disposal cell wil be surveyed by scanning the area as shown in Figure 3.2, colecting samples on a ten meter grid, and recording exposure rate measurements at each 10-meter grid location. Samples will be analyzed by the on-site gamma spectrometer for U-238, U-235, Th-232, and Ra-226..

U-234 activity will be calculated based on U-238 and U-235 values.

3. Additional sampling will be conducted to delineate the area of elevated activity if scanning and/or sampling results indicate that material exceeding the Option i limits is present.

4. Analytical results from the sampling specified above will be used to calculate the average and maximum activity of the survey unit, and the area-weighted avarage activity of areas of elevated activitf. A statistical test such as a t-test will be used to demonstrate that criteria have been achieved at the 95% confidence level.

6. If survey and/or sampling results indicate that material exceeding the criteria specified Section 3.3.1.2 has been placed in the disposal cell, the material will be excavated and transported to the RMSA pending offsite disposal.

6. KMC will afford the NRC an opportunity to perform a confirmatory survey of treated material placed in the OlW cell before the final cap is installed.

3.3.1.4 Radiation Protection All decommissioning activities will be monitored by the site health physics department and will comply with the site Radiatior Safety Plan (RSP). The RSP addresses both personnel and environmentai monitoring to be implemented during decommissioilng activities. The RSP has beer established to ensure compliance with NRC's radiation exposure limits specified in 10 CFR 20.

3.3.1.5 Quality Assuranm Considerations in 1989, the American Society of Mechanical Engineers published " Quality Assurance Requirements for Nuclear Facility Applications"(NQA-1). This document, cusNng site Decommissioning Plan 8

Fioname: Pt 4 Decommissionang Plan

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j revi' sed in'19'94, sets forth quality assurance requirements for the decommissioning of j

nuclear facilities. NUREG/CR-5849, " Manual for Conducting Radiological Surveys in

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Support of License Termination" references NQA-1 as an appropriate quality assurance standard. KMC established a site-specific quality system in accordance with NOA-1.

1 This quality system is now being modified to comply with the ANSI /ASQC ISO 9001 j

standard, 'Model for Quality Assurance in Design / Development, Production, installation, and Servicing", which includes all aspects of NQA-1.

Decommissioning and final survey activities will be performed under the Cushing quality system. Table 3.3 lists by category the quality assurance requirements of NQA-1 and the ISO 9001 standard. All are addressed within the Cushing quality system.

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Irmtructions, Procedures, and Drawings Secdon 4.2 & 4.3 5

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Process Control Section 4.9 9

r+=791 end Testing Seebon 4.10 10 & it Control of tre Testing, and Measuring Egt Sedion 4.11 12 t.= =<-w and Test Status Sechon 4.12 14 Control of ha.,,-26 Product Sec6cn 4.13 15 Corrective end Preventative Acton Sechon 4.14 16

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Sea 6on 4.19 Servicing Slotsbes!TMnr Sechon 4.20 13 Cushing See DecommissorWng Plan Flienemo PR 4 Decor'imesonirig Plan

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