I &,o I ý* V9t

LIT!O SlAMfM="~rR REGULATORY CO~kRUOt4

WAONOaTW. D. C. 2M

February 16, 1979

MEMORANDUM FOR:

FROM:

SUBJECT:

Ross A. Scarano, Section LeaderUranium Mill Licensing Section

John J. LinehanUranium Mill Licensing Section

SAFETY EVALUATION REPORT (SER) FOR MINERALSEXPLORATION COMPANY (MEC) SWEETWATER UP.ANIUM MILL

Attached for your review and approval is the SER for the MEC

Sweetwater Mill.

Urnhn J. LinehanUranium Mill Licersing Section

. "'43 Enclosure:As stated

7 908170 c~

S I.

SAFETY EVALUATION REPORT

SOURCE MIATERIAL LICENISE

.IERALS EXPLORATION COMPANY

SWEETWATER MILL

DOC-E T . 0 ,-5Q4

LICE:,SE NO. SUA-1350

FEBRUARY 16, 1979

, FIA; if

9510060096 790216PDR ADOCK 04008584C PDR

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TABLE OF CONTENTS

1.0 DESCRIPTION OF PROPOSED ACTION

2.0 REVIEW SCOPE

3.0 AUTHORIZED ACTIVITIES3.1 Facility Description3.2 Mill Process

4.0 FACILITY ORGANIZATION AND ADMINISTRATIVE PROCEDURES4.1 Organization4.2 Radiation Safety Staff4.3 Minimum Technical Qualifications for Radiation

Safety Staff4.4 Admininstrative Procedures4.5 Audits and Inspections4.6 ALARA Program4.7 Personnel Training

5.0 RADIATION SAFETY CONTROLS AND MONITORING5.1 Effluent Control Techniques5.2 In-Plant External Radiation Monitoring Program5.3 Personnel External Monitoring5.4 Contamination Surveys5.5 In-Plant Airborne Monitoring Program5.6 Protective Equipment for Personnel5.7 Bioassay Program

6.0 ENVIRONMENTAL AND EFFLUENT rONITORING PROGRAMS

7.0 RESTRICTED AREA MARKINGS AND ACCESS CONTROL

8:0 EMERGENCY PROCEDURES

9.0 DECOMMISSIONING AND RECLAMATION

10.0 BONDING

11.0 CONCLUSION

1.0 DESCRIPTION OF PROPOSED ACTION

By application, dated November 16, 1976, and numeroussupplements, Minerals Exploration Company (MEC) submitted arequest for a source material license to operate a new uraniummill in Sweetwater County, Wyoming, in an area known as theRed Desert.

A Final Environmental Statement, FES (NUREG-0505), issued inDecember, 1978, a geotechnical and hydrological safety analysisof the tailings impoundment and this Safety Evaluation Report-provide the bases for conditioning a five-year term license.

2.0 REVIEW SCOPE

The in-plant, safety review of the NEC Sweetwater Uranium.ill included an evaluation of the initial application datedNovember 16, 1976, a June 14, 1977 meeting with NEC to discussdeficiencies in their application, review of a completelyrevised application, dated July iI, 1977, a July 27, 1977meeting with NEC to discuss remaining unresolved issues, reviewof a completely revised application, dated August 10, 1978,with supplements, dated October 31, 1973 and January 8 and 24, andFebruary 5, 1979, and a final January 11, 1979 meeting with MECto resolve all outstanding issues.

In addition, an inspection will be conducted by I&E, Region IVstaff to review NEC's development and implementation ofadministrative and operating procedures and monitoring programsprior to mill startup. Any problem areas identified by I&E will becorrected prior to startup of mi.ling operations.

3.0 AUTHORIZED ACTIVITIES

3.1 Facility Description

The mill facilities will consist of several buildings ofassorted sizes and an array of various sized tanks designedand arranged to present a well-integrated compact appearance.The mill site. will occupy about 400 acres with a surfacearea of about 300 acres for the tailings impoundment.

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3.2 Mill Process

A schematic flow chart for the proposed mill process isshown in Figure I. Ore from the open pit mines will behauled by truck to a probe tower where its uranium oxidecontent will be determined and will then be trucked to themill stockpile. A front end loader will feed the oregrade material through a hopper into the grinding circuit.

The proposed uranium mill will *operate 24 hours per dayand process an average of 3,000 tons of ore per day, 365days per year, over its expected life of 15 years. Basedon a 0.048 percent average grade of ore and an estimated91.7 percent recovery rate, the mill will produce approximately2,650 pounds of concentrate per day, or about 900,000pounds per year o,,er its expected life. Ho~iever, sincethe daily and annual ore grade and the percent recoveryimay vary and result in a fluctuation in production ratethe mill will be authorized to produce a maximum of 3,200pounds of uranium concentrate per day, averaged over ayear. This fluctuation could result in a maximum increasein ore pad, grinding, and yellowcake stack effluents andresulting doses of 20% in any one year over those presentedin the FES. Based on this 20%, the maximum organ dose toan individual at the site boundary would only increasefrom 3.3 to 4.0 mrem/yr to the lung, as compared to thefuture 40 CFR 190 dose limit of 25 mrem/yr. Since theaverage grade of ore over the 15 years will remain at0.0043, and since the radiological source term for tailingswas based on the tailings area existing at the last yearof operation, the source term and resulting doses fromtailings will not vary from that presented in the FES.

The ore will first be processed through a semiautogenous AA

mill circuit to reduce its size. The product from thiscircuit will then be pumped to a set of hydrocycloneswhere the pulp ore is separated by size. The fine orepulp will then be discharged into rubber-lined leach tanksand mixed by mechanical agitation with acid solution todissolve the uranium minerals. The discharge from theleaching circuit will be pumped to a countercurrentdecantation system where the uranium-rich solutionwill be separated from the tailings in multiple stagesof thickeners and filters. The tailings will be pumped toan imnoundment and the uranium-rich solution will beclarified and then pumped to a solvent extraction system.

Waler from M•ine

SICAm

0le Blendtd by

Froril- gd LOodtrCo•la, ji•

Fuel OilAnda A,,

Arnmoaii Gas O qy''c

Uranium Oxide

Figure I . Generalized Block Flow Diagram of Mill Operations.

.v - 4

In the solvent extraction process the uranium is removedfrom the pregnant aqueous solution by solvent ion-exchangeand concentrated into an organic liquid. Most impuritiesremain in the water and the uranium is substantiallyconcentrated. In the Sweetwater mill this extractionprocess will take place in four sets of mixing and settlingtanks with organic liquid and water moving in oppositedirections (countercurrent) through the sets of tanks.The barren aqueous solution will be recirculated to thecountercurrent decantation wash circuit or discharged astailings. The pregnant organic solvent will be cycledto another set of tanks for reextraction of uranium intoammonium sulfate solution. The final uranium concentrationwill be about 25 g/L. The barren liquid will berecirculated to the extraction system.

The ammonium sulfate-uranium solution will be heated andtreated with anhydrous ammonia, precipitating crudeammonium diuranate. The precipitate will be washed,dewatered, and calcined, yielding a product containingabout 90t' U3 09. The material then will be crushed tominus 1/4-inch sieve size and packaged in steel drums forshipment. The entire drying, crushing, and packagingoperation will be conducted in an isolated area undernegative pressure to contain and collect by wet scrubbingairborne uranium particulates.

4.0 FACILITY ORGANIZATION AND ADMINISTRATIVE PROCEDURES

4.1 Oroanization

The General Manager for the Sweetwater project reportsdirectly to the Corporate Manager of Operations for MineralsExploration Company and is responsible for coordinating anddirecting the activities of all project personnel and allphases of the mining and milling project.

The Mill Superintendent reports to the General Manager andis responsible for: mill operations (production, costs, andquality control of operations and product), mill safety andmetallurgy.

The Safety and Environmental Administrator reports directlyto the General Manager and is responsible for environmentalprotection, radiation, and industrial safety programs forthe mining and mill project and all records necessary to comply

_

with regulations and requirements of the NRC, EPA, MSHA,and other government agencies. He will serve as managementsurveillance and an advisor to the Maintenance, Mill andMine Superintendents and direct project security programs.Reporting to the Safety and Environmental Administrator arethe Environmental Assistant and Safety Technician.

4.2 Radiation Safety Staff

The Safety and Environmental Administrator who reportsdirectly to the General Manager is the individual responsiblefor the radiation safety program. He is responsiblefor ensuring that monitoring conducted by the Safetyand Environmental staff and/or laboratory is conducted ina proper and an accurate manner and has the authority tocancel, postpone or modify any process, or operation whichproves an immediate radiological hazard to employees.This decision is subject to revocation only by the GeneralManager or his designate after consultation. This positioncarries full authority for the operations and requirementsof the radiation safety program and the Safety and EnvironmentalAdministrator has the proper authority necessary todischarge his duties.

The Environmental Assistant reports directly to theSafety and Environmental Administrator and is responsiblefor supervising the environmental protection and radiationsafety programs.

4.3 Minimum Technical Oualifications for Radiation SafetyStaff

The following are the minimum technical qualificationsrequired of individuals responsible for the radiationsafety program.

1. Safety and Environmental Administrator

a. DS degree in the physical sciences, mathematics Orengineering from an accredited college or university,equivalent experience, or a combination of educationand experience. Equivalent experience will be at leastfour years of relevant radiation safety experience.

b. Specialized training in radiation protection, with atleast bi-annual refresher course.

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c. Training and experience in management.

d. A working knowledge of radiation detection instruments,biolocical effects of radiation and mathematics of radia-tion.

2. Environmental Assistant

a. An associate degree in science or a high school diplomaand 2 ,ears equivalent work experience.

b. One year of specific training or- work experience insam.pling and analytical procedures.

These minimum. technical qualifications assure that the idividualsfilling these radiation safety positions have an adequateformal educational background and/or the necessary specifictraining and experience to carry out the duties of thesepositi ons.

4.4 Administrati4ve rccedures

MEC has com.itted to maintaining an operating manual coveringeach phase c- o.erations which will be written by appropriateDepartment staff and will be made available to each mill andmaintenance emoloyee. The Safety and Environmental Administratorwill approve the health and safety aspects of the operatingprocedures. The manual will be on file in appropriatew,'ork areas and updated as necessary to reflect any processor operationai changes.

~XAA

The mill licensin4 section staff have further required that thelicensee also maintain operating procedures for the radiation

e program the environmental monitoring and controlprocram and th~at written procedures pertaining to all activitiescarried on in an area shall be available in each area whereradioactive material is processed, handled,.or stored and shallbe reviev,ied at least annually. In addition, the staff hasalso required that for any worl or maintenance for whichthere is no effective operating procedure, and for any non-routinemaintenance or re work, -that a radiation work permit signedby the radiation safety staff be prepared and used for performingthese activities.

The staff has determined that these administrative procedures areadequate to assure that all operations are revi ewed for healthand safety problems prior to performance.

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4.5 Audits and Insnections

.EC has committed to a monthly inspection of work andstorage areas and practices with respect to radiationsafety. All monitoring and exposure data will be reviewedmonthly to ensure compliance. Any trends or deviationsfrom the "as low as reasonably achievable" (ALARA) philosophywill be addressed. A formal report will be prepared andreviewed by the General Manager and all department heads.The report will address any upward trends, unusual dis-charges, problem areas, monitoring data, items of regulatorynon-compliance, and recommendations for necessary correctiveactions. The report will also include an evaluation ofthe adequacy of the implementation of license conditions.

In addition, NEC has committed to the following auditsand inspections by Corporate Staff:

a. A semi-annual audit including review of operatingprocedures, exposure records, monthly inspection reports,training proarams, safety meeting reports, and theALARA philosophy. All phases will be evaluated todetermine the total programs' effectiveness.

b. Corporate management will inspect and review theproject, its programs and records on at least anannual basis.

c. The Corporate Medical Department will inspect,review aid approve the project health physics safetyprograms and records on at least an annual basis.

In addition to the ab'ove, the mill licensing staff have conditionedNEC's license to reouire a daily documented visual surveillanceof all mill areas by the operating mill foreman to insure properimplementation of good radiation safety practices and a weeklyinspection by the Environmental Assistant of all work andstorage areas and a report to the Safety and EnvironmentalAdministrator on any items of non-compliance with operatingpr-ocedures, license reouirements, or safety practices affectingradiological safety.

The mill licensing staff have also required that all suchinspections and any required reports and corrective actions willbe documented and documentation retained for at least fiveyears. 4

MEC's audit and inspection program, as supplemented by the specificlicense conditions developed by the staff and discussed above., iscomparable to programs that have been proven to he effective atother mills and at other types of facilities handling radioactivematerials.

4.6 ALARA Prooram

MEC has committed to keep occupational radiation exposuresas lcw as reasonably achievable. Any trends or deviationsfrom ALARA will be addressed by the Safety and EnvironmentalAdministrator in his monthly inspection report. To ensurethat the philosophy is being pursued, MEC Corporate staffwill conduct an audit on a semi-annual basis. The CorporateMedical Department staff will conduct the audit. Itemsto be reviewed are:

1. Operating procedUres2. Exposure records3. Monthl'.y inspections reports4. Training Program5. Safety meeting reports

The mill licensing staff have further required that a formalreport of a semi-annual review of all audits and inspectionsas well as e-mployee exposures (including bioassay data), effluentrelease data and environmental monitoring data shall be preparedby the Sa-fet and Environmental Administrator and along with hisconclusions and recommendations submitted to the General Managerand Corporate M-1edical or Environmental Sciences Department todetermine (1) if there are any upward trends developing in.personnel exposures for identifiable categories of workers ortypes of oerations or effluent releases, (2) if exposures andeffluents micht be lowered under the concept of as low asreasonably achievable, and (3) if equipment for effluent andexposure control is being properly used, maintained and inspected.This reCuirement for a formal report was developed by the staffto provide a document which would clearly indicate MEC's compliancewith the ",LA,," concept.

_ 0 _

MEC's acceptance of this license requirement for a formalreport' along with MEC's audits, inspections, employeetraining, and administrative procedures, demonstratesboth a commitment and a mechanism to ensure compliancewith the "ALARA" concept.

4.7 Personnel Training

All new employees will receive a minimum initial trainingin radiation safety, industrial safety and process operations.The Safety and Environmental Administrator will administerthe safety and radiological training programs.

Basic indoctrination in radiation protection will be givento all employees prior to being assigned to work in the millarea. Detailed training will then be given during the firstmonth of employment. Safety meetings will be conducted monthlywith at least 30 minutes devoted to radiation safety. Indoctrinationtraining will include a written examination. Employees and theirrespective supervisors will sign a statement that the employeereceived radiation protection training, successfully completedtesting of that training, and the date the training was received.The signed statement and the examination will be retained.Retraining will be given at least every 2 years and will also bedocumented.

Additional training will be given to supervisors sothey will be able to provide specific job-related trainingand evaluate their subordinates' performance. Supervisortraining will be documented in the same manner as indoctrina-tion training, with retraining required every 2 years.

Mill employees will receive on-the-job training fromsupervisors. For maintenance personnel, a continuoustraining program will be administered to ascertain thatsafe practices and proper procedures are followed

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during'both the operation and maintenance of equipment.Mai ntenance employees' job performance with respect toradiation protection will be appraised annually by theirsupervisors to determine if retraining is necessary.

Technicians performing radiation protection dutieswill receive additional training consisting of lecturesand/or on-the-job training. Oral and demonstration testswill be given to evaluate the technician's job performance.Documentation will include written examinations kept inthe employee's personnel folder.

The overall training program proposed by MfEC is consistentwith training programs within the nuclear industry thathave proven to be effective.

5.0 RADIATION SAFETY CONTROLS AND M',ONITORING

5.1 Effluent Control Technicues

The mill was designed to combine efficient operationswith minimized environmental impacts and safety hazards.To this end the mill circuit is essentially enclosedand wet, thereby eliminating the hazards associated withdry operations. The design of the mill is suc.h thatany leaks or spills will be collected and recycled tothe appropriate part of the process. Emission controlequipment is listed in Table 1.

The dust collecting, venting and fume control systems inthe plant are designed to control emissions when the plantis operating at a design rate of 3300 TPD.

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.Table 1

-. "- SION CONTROL EOUIPMFNT SUMMARY

Location

Ore 11i11 Feed Area

Leach. Tanks

Yellowcak-e Precipitators,Thicieners and Centrifuge

Yel lo',..ca!,e Dryer

Yellowcake ProductDru minc Area

Emeroenc'.' Power Generator

Labora-crv Hoods

Emission Control Equipment

Wet Scrubber

Wet Scrubber

Wet Scrubber

Wet Scrubber

Wet Scrubber

None

!,!et Scrubber

The failure c; all dust collector, ventilator and scr-ubberfans 2ill be alarmed in the appropriate control rooms asfoll ows:

a. Ore recei,,inn area.

b. Leach tank scrubber exhaust fan. Failure of the watersupply to the scrubber .ill also be alarmed.

c. Solvent extraction building ventilator fans.

d. Yellow:cak':e thickener and precipitation tank .scrubberexhaus: fan. Failure of the water supply to thescrubber will also be alarmed.

e. Yello.'ca-e dryer scrubber exhaust fan. Failure of thew.ater s.:Diy to the scrubber will also be alarmed.

f. Yel lo,;ca-..e packaging wet collector fan.

:-.-.;<.•-•.,:- .•...

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Failure indication time in all cases is less than five seconds.Scrubber circuits from the concentrate drying and packagingareas will be checked every hour and documented. Manometerreadincs will be recorded once per shift and such readings willbe documented to ensure proper operation.

The stiff has further required by license condition that operationsshall be immediately suspended in the affected areas of the millif. anm of the emission control equipment, for the ore feed orthe yelle",,cake drying or drumming areas specified in Table 1 isinoperative.

Spillace of solids, slurry and solutions will be minimizedby level controllers and high level alarms on all major tanksand sumsJs. If spillage occurs material will be contained bydikes or curbs and will drain or be directed to floor sump pumpsthat will discharge back to the mill circuit. Spills from someuncurbed outside tank,-s will flow via a specially excavatedchannel to a catchment basin where they will be contained andsubsee.n!tely cleaned up.

The fo-io',.-'inc is a description of the specific effluent control

techniqu•.es to be utilized at various staoes in the mill circuit:

a. Ore storace pads..-I ,,- b recuired to minimize dispersal of dust from the

ore si-s by water sprinkling or other dust suppressiontechnirues, unless a documented w,,eekly inspection indicatesthat e moisture content of the ore and/or weather conditionsare csn:roiling dusting. Runoff from the ore stock pile asa result of rain or snow will be collected in the generalmirll drainagýce system and used as mill process water.

b. Ore P.eceiving and Grinding

The ore is normally fed to the plant at a moisture contentof I0-14% which should not cause any dust problems. Toass'ure , .rctec.rion of the env'ironment, the dust collectingsystem for this plant is designed to collect dust from thedr"' ore which may be introduced into the system infrequently.All en-rained air from these operations, together with any,dust which may be present, are vented through a wet scrubber.

c. Le2chi;h4

TheC leach tank effluents vwill be vented through a wetscr'ubber and the acid removed by the scrubber will bere--urne2d to the mill circuit.

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d. Washing and Clarification

At this wet stage of the operation, the uranium chargedleach solution is separated out and the tailings andleaching solution discharged to the tailing impoundmentarej. No emission control system is utilized at thisstage of the process.

e. Solvent Extraction

Kerosene vapors from the solvent extraction system willresult from evaporation and will escape to the atmospherethrough building ventilator fans.

f. Precipitation

At this stage of the process, the uranium bearing solutionis neutralized with ammonia to precipitate out ammoniadiuranate, yellowcake, which is thickened by dewatering.Effluents from this process are vented through a wetscrubber.

g. Concentrate Drying and Packing

The thickened yellowcake slurry is further dewatered bya centrifuge and pumped to a multiple hearth furnacefor drying. The dried yellowcake is then passed througha crusher and then packaged in steel drums. The entiredrying and packaging operation will be conducted inan isolated area with a negative ventilation pressureequipped with self-closing access doors. Both thedrying and product packaging stages of the processwill be equipped with wet scrubbers to collect greaterthdn 95 percent of the uranium particles contained inthe process effluent. The emissions from the yellowcakeprecipitator-thickener-centrifuge scrubber, the dryerscrubber, and product drumming scrubber all dischargeto a single common stack.

h. Tailings impoundment

MEC will be required to prevent release of airborne particulatesfrom the tailings pile by maintaining a water cover over thetailings. If any tailings are not covered by standing waterREC will be required to take measures to minimize dispersalof blowing tailings. The effectiveness of these measures usedshall be evaluated weekly by means of a documented tailings areainspection.

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The equipment and techniques to be used by MEC forprocess effluent control are considered to be stateof thelart for the uranium milling industry.

5.2 In-Plant External Radiation Monitoring Program

Some measureable external radiation exposure may beanticipated in areas associated with incoming ore and in theproduct storage areas, where the radiation level willincrease with time of storage of the product because of thebuildup of daughter products. Under unusual conditions,intermediate or final products may accumulate in pipes andtanks and create local radiation areas. ,EC has committedto a survey of the restricted area quarterly for the firstyear and semi-annually thereafter, to determine the levelsof external radiation present at representative locations.Twenty-two (22) locations have been identified within therestricted area for survey. The staff have reviewedthese points and found both the number and locations to beadequate. In addition, the staff have determined that thesurvey meters available at the mill will be adequate forthese surveys.

Instruments will be calibrated after repair and asrecommended by the manufacturer or at least semi-annually, whichever is sooner. To assure that theinstruments operate properly before each use, a checksource will be used to assure operating order.

MEC's in-plant external radiation monitoring program alongwith its personnel external monitoring program is adequatefor the hazards anticipated and meets standard healthphysics practices.

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5.3 Personnel External rionitoring

All mill and maintenance employees will wear TLD badgesduring working hours. The badges will be exchanged ona monthly basis, and the exposed badges will be returnedto the supplier for processing and reading. In addition,stationary badges or dosimeters will be placed in selectedlocations, determined under actual operating conditionsand read quarterly.

MEC has committed that any badge exposure exceeding 25percent of the maximum permissible exposure in any calendarquarter will be evaluated and the situation causing theexposure will be investigated and corrective actioninitiated promptly.

This program meets the guidelines described in "IAEASafety Series Rlo. 43," pages 19 and 20.

5.4 Contamination Surveys

The staff has recuired that surface contamination surveys(both smear and total contamination) be conducted at leastweeklv in eating areas, change rooms, control rooms andofTices. In addition, the staff has also required that theoperating -ill Foreman conduct and document a daily visualsurveillance of all mill areas to insure proper implementationof good radiation safety practices, including good clean uppractices to minimize unnecessary surface buildup of radioactiveparticulates.

The above is an acceptable surface contamination control programthat meets current standard health physics practices.

In addition, if surface contamination levels in theeating areas, change rooms,control rooms and officesexceed the applicable values in Annex C, the area will bedecontaminated and a study performed to determine thecause of buildup and corrective measures taken to preventrecurrence.

.. . C

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MEC has proposed that decontamination of facilitiesand equipment to be released from the restrictedarea meel the limits in Annex C, Guidelines forDecontamination of Facilities and Equipment Priorto Release for Unrestricted Use or Terminationof Licenses for Byproduct, Source, or SpecialNuclear M.aterial, which is an informal guidedeveloped by NMISS staff.

In addition, all contaminated clothing will be laundered

on site.

5.5 In-Plant Airborne Monitoring Program

Most airborne contaminants in the mill are expectedto result from localized sources. Because con-centration gradients in the vicinity of points of releaseare expected to exist and produce large variations,frequent measurements are required for exposure evaluationand control measures.

The rationale for conducting an airborne monitoringprogram is based upon the following facts. During theinitial stages of processing the ore, U, Ra-226, andTh-230 are expected to be in equilibrium; but duringsubsequent operations, this equilibrium will be disturbed,and the concentration of individual radionuclides must bemeasured for the assessment of hazards. In the precipita-tion and product recovery sections, airborne materialexpected would normally be uranium. Radon concentrationsmay occur near ore storage bins and crushing and grindingcircuits. Exposuresdue to airborne concentrations mayalso occur in sample preparation and assay rooms. Inmany cases, because of the physical layout of the process,airborne effluents in one area may tend to influenceexposures in other adjacent areas.

Routine Sampling

Airborne radioactivity will be sampled at at least seventeen loca-tions. These locations are based on expected employee occupancyand sources of airborne radioactivity. Thirteen of the 17

IC C

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locations will be sampled a minimum of once per monththe other four at least quarterly. All sampilei will beanalyzed for uranium and Rn-222 daughters. In addition,_ýfilter samples collected in representative areas will beanalyzed for Ra-226 and Th-230 semi -annuallI.

In addition, the staff has required that in-plant airbornemonitoring be performed under conditions typical of employeeexposures and that along with results of airborne activity,a record cf the state of operation of both process andeffluent control equipment and ventilation conditions bekept.

Personnel breathing zone samples (2-8 hours) will beworn quarterly by operators at five representative processlocations ana analyzed for uranium. In addition, portableair sampling will be conducted on representative employeesof the yellowcake area, employees involved in maintenanceof yeliowcake equipment, and additional representativeemployees in locations where airborne uranium dust issuspected.

The staff have reviewed this sampling program and havefound the number, type, and location, as well as thefrequency of sampling, to be sufficient.

ExRosure Calculations

A time study/ of all mill and maintenance employeeswill be conducted to determine the amount of time spent ineach area. This information, along with the area airborneconcentration, will be used to calculate exposures.A computer program or equivalent method will be usedto determine weekly and quarterly exposure. Any abnormalexposures will be included in the exposure calculation andrecords.

On a periodic basis, portable sampling pumps will beattached to employees during the shift in order todeterm•ne time-weighted averages. In addition, timerecords will be kept during a non-routine maintenanceof spill to maintain a close accounting of individuals'exposures.

g

If an employee reaches an action level of 25 percent of.iPC based on TE (time weight exposure) over a periodof one quarter, the Safety and Environmental Administratorwill inftitute an investigation of their work recordand exposure history to identify any problem areas.If any problem areas are noted, they will be studiedand necessary corrective measures taken to ensure that theexposure is as low as reasonably achievable.

NEC's program for monitoring in-plant airborne activityand determination of employee exposures is adequate andcomparable to the programs carried out successfully atexisting mills.

5.6 Protectile Equipment for Personnel

1. Showers, Change Rooms, and Protective Clothing

Persons required to work in refined product areasor perform maintenance on equipment from these areaswill be issued coveralls. These coveralls will belaundered in facilities maintained at the mill forthis purpose.

All mill personnel will be provided with changefacilities including shower facilities so that theymay leave their work clothes at the mill. A washer anddryer will be provided and all coveralls will bewashed on the property. Employees receiving direct bodycontamination wil-l be surveyed for contaminants aftershowering. They will not be allowed to leave therestricted area without authorization of the Safetyand Environmental Department.

The staff have required that prior to leaving therestricted area, all mill employees either shower

-or monitor themselves after changing clothes. Ifclothing is not changed then clothing shall also bemonitored. A radiation survey meter shall be availableat the exit to the change room. In addition, thelicensee shall perform spot surveys for alpha contamina-tion at least quarterly on workers leaving the plant. Alphacontamination on skin or clothes greater than 1,000 dpm/l00 cm-shall be cause for additional showering or decontaminationand an investigation by radiation safety staff.

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The above program is adequate to minimize as much asis reasonably possible the spread of contaminationfrom the plant process areas to unrestricted areas.

2. Respirators

MEC's respiratory protection program is based onRegulatory Guide 8.15, "Acceptable Programs forRespiratory Protection" and rUREG-0041, "Manualof Respiratory Protection Against Airborne RadioactiveMaterialas. Tihe program will be directed by theSafety and Environmental Administrator.

Respirators w.ill be required on routine operationsat the discretion of the Safety and EnvironmentalAdministrator or Nill Superintendent, and on anyemploy,'ee who enters the yellowcake areas (drying andpackaging).

The staff has added a condition stating that "Notwith-standing any of the protection factors for respiratoryprotective devices specified in Appendix D of Section 5of the licensee's application, the licensee shall notapply :rotection factors in excess of those specifiedin Table 1 of QRC Regulatory Guide 8.15 in estimatingemployee exposures.'

5.7 Bioassa' Procram

NEC's bioassay program will consist of the following:

a. Urine specimens shall be routinely collected from all regularmill workers and all personnel involved in maintenance tasksin which yellowcake dust may be produced. Specimens shall becollected monthly, as close as is reasonably possible, after43 hours and not more than 96 hours of last exposure. Thereasurec2ent sensitivity shall be 2 wg/l or less. A specialurinalysis shall also be performed if there is any reason tosuscec-tLai inhalation exposure to yellowcake exceeding40 x 10 uCi-h/ml in a period of one work week.

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A baseline urine sample shall be obtained from any new worker,who will be subject to urinalysis, prior to start of work.

b. In vivo ,7easurements shall be performed on all mill workers,all yellowcake maintenance workers, and all other maintenanceworkers routinely assigned to work in the mill at least onceevery two years with equipment capable of measuring 9 nCi orless of uranium in the lung. In vivo counting shall be per-formed each year on approximately half of the above workersand any worker whose intake of radioactive material for anycalendar quarter since his last in vivo count exceeds 25% of theintake that would result from exposure to the concentration ofradioactive material listed in 10 CFR 20, Appendix B, Table 1for a period of one quarter.

Baseline in vivo measurements shall be performed on all newworkers who will be subject to in vivo counting the firsttime the in vivo counter is available.

c. Action levels based on bioassay measurements shall be inaccordance with Tables 1 and 2 of NRC Regulatory Guide 0.22,"bioassay at Uranium '-ills" (July 1978). In addition, allbioassay results shall be evaluated by the Safety andEnv.'ironu.,ental Administrator and Corporate INMedical Department.

d. In addition to any evaluations of employee exposures and anynCtifications required pursuant to Sections 20.103 and 20.405of 10 CFR Part 20, the licensee shall make a formal documentedevaluation if bioassay measurements exceed any of the followingcriteria:

(1) The urinary uranium concentration exceeds 30 iig/l for anytwo consecutive sampling periods.

(2) The urinary uranium concentration for any measurement

exceeds 30 ug/l.

() Any in vivo thorax measurement exceeds 16 nCi.

e. Urinalysis results exceeding 15 lig/l shall be reported to theSafety and Environmental Administrator within ten days ofspecimen collection.

Urinalysis results exceeding 30 ug/l and in vivo results exceed-inn 16 nCi shall be reported to the Safety and EnvironmentalAdministrator by telephone.

S 4 I

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f. Prevention of specimen contamination shall be inaccordance ',;ith Section C.6 of NRC Regulatory Guide2.22 (July 1973).

g. ThQ licensee shall implement a documented qualitycontrol program for urine specimens that includesbackground samoles, blanks, and spikes and alsocriteria for requiring repeat collection andanalysis. This quality control program must be approvedby the NRC prior to implementation.

h. If an individual wearing a respirator is subjected to

a concentration of' vellowca!-e in air within a period of 1week such that the exposure if he or she had not beenwearing the device would have ex>ceeded 40 x C nCi-h/nl(v,where C is the concentration value given in 10 CFR Part20, Appendix E, Table i, Column 1, for soluble naturaluranium), urinalysis should be performed to test theactual effectiveness of the respirator.

The above bioassay program was developed by the staffusino elements of i-E`s proposal and elements of theprogram outlined i" Requl-tory Guide 8.22, Bioassayat Uranium Mills.

The procram is ccmparable to that outlined in RegulatoryGuide 8.22 and should be adequate to indicate any uptakeand/or retention of radioactive material by mill personnel.

6.0 [NV.IR.:.EN.TAL AND EFFLUENT ONITORING PROGRAMS

.EC will conduct an effluent and environmental monitoringprogram as specified in Tazbles C-3 and C-4 of their applicationand modified by Condition No. 43 of their license. The environmentalmonitoring program was designed around the source terms,radionuclides present, meteorological considerations, identifiablepathways, and receptors.

This monitoring program is the same as that presented inTable 6.2 of the FES, except for changes in yellow,,cake areastack and air particulate perimeter monitoring. The frequencyof isokinetic sam.ing of the yel lowvcake area stack was changedfrom monthly to quarterly and one of the three 24-hour/everysix days air particulate perimeter samples has been changed toa continuous sample, resulting in two continuous air particulateperimeter samples and twio 24-hour/every six days air particulateperimeter samples. The staff has determined that these changesdo not affect the quality of .:_EC's monitoring program and thatthe revised program is equivalent to that described i-n theFES.

7.0 RESTRICTED AREA [.1ARKINGS AND ACCESS CONTROL

The mill and tailings impoundment will be fenced and postedwith signs in accordance with 10 CFR 20.203. Parking facilitiesfor employee and visitor vehicles will be outside this fencedarea. A gate adjacent to the office will provide access forpersonnel reporting on and off shifts.

By license condition the licensee has been exempted from therequirements of Section 20.203(e)(2) of 10 CFR 20 for areaswithin the mill, provided that all entrances to the mill areconspicuously posted in accordance with Section 20.203(e)(2)and with words, "Any area within this mill may contain radioactivematerial."

All visitors will be required to regi~ster and will be escortedwhile within the secured area.

Contractors having work assignments ,ill be given security,safety and radiation protection orientation prior to performingtheir duties without escort.

8.0 EMERGENCY PROCEDURES

The Safety and Environmental Administrator will establishemerenc-' procedures for the project. A detailed Spill Prevention

Countermeasure and Control plan will also be prepared. Accidentswhich are possible for this type of activity have been identifiedin Section 5 of the FES (NUREG-050-). Precautions and measureswhich the applicant will take to reduce the possibility ofoccurrence of these accidents include the follow.-ing:

1. Tailings Impoundment

MEC w.ill make and document at least daily an inspectionof the entire tailings retenticn system including theembankments of the tailings retention area and the exposedprotective soil cover over the liner and make repairs ifany erosion occurs.

KEC will also maintain a minimum of 5 feet of freeboard betw eenthe top of the tailings dam and the pond level throughout theproject life.

2. Fire Protection

Heat sensors will be strategically located in the mill todetect fires and approved fire extinguishers will beavailable throughout the site. Selected emplEyees will

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be trained in fire control techniques. A light watersystem will be installed in the solvent extraction building.This syttem consists of necessary tank?, proportioners,piping, mixing valve, distribution valves, and individualsprinklers strategically placed. Foam activation will bevia heat sensors.

3. Spill Prevention and Containment

Tanks will be'equipped with high level alarms to reducethe possibility of spillage due to tank overflow. Dikesand/or curbs will be constructed around process andstorage tanks (excluding the water, ammonia, and sulfuricacid tanks) to confine the material in the event of tankspill. In the event of an ammonia tank spill, the materialwould be expected to quickly evaporate. A sulfuric acidtank spill would flow via a specially excavated channel tothe catchment basin where it would be fully contained andsubsequently cleaned up.

9.0 DECOMMISSIONING

By letter dated January 19, 1979, MEC submitted to the Commissiona decommissioning and stabilization plan for the SweetwaterProject that outlines a generalized program to return the landsdisturbed by the project to their former use and productivity.The plan addresses facility decommissioning, tailings stabiliza-tion, and land reclamation by planned revegetation.

MEC has further committed to submission of a detailed decommissioningplan for approval by the Commission prior to terminating themilling operation and Ub naintenance of a bond with the Stateof Wyoming until successful reclamation has been accomplished.In addition, M,1EC has committed to decommissioning of facilitiesor equipment in accordance with Annex C, "Guidelines. forDecontamination of Facilities and Equipment Prior to Releasefor Unrestricted Use or Termination of Licenses for Byproduct,lource or SNM," which is an informal guide prepared by NMSSstaff.

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10.0 BONDING

A surety bondi in the amount of $10,075,000 has been postedwith the Wyoming Department of Environmental Quality (DEQ)for the disturbance caused by first year site activities,to cover reclamation of the mill and mine sites and tailingsimpoundment area in the event of a forfeiture. During thisfirst year (11/78-11/79) there will be no milling activities.The mill is not scheduled to start up until mid-1980. Prior tothe initiation of milling activities and the associated generationof tailings, MEC will be required by license condition to revisethe bond held with the Wyoming DEQ to include tailings and millsite reclamation costs reviewed and approved by the NRC staff.

11.0 CONCLUSION

Upon completion of the safety review of the licensee's applicationand a review of this SER and the proposed license conditions byI&E, Region IV and Headquater staff, the staff has concludedthat issuance of a license to MEC, subject to the additionalconditions developed by the staff, will not constitute an unduerisk to the health and safety of the public, and has determinedthat the application and supplements fulfill the requirementsof 10 CFR 40. The staff has further determined that conformanceby MEC to their proposed conditions, as well as those developedby the staff, should ensure a safe operation.

The staff, therefore recommends that MEC be issued a licensesubjected to the following conditions:

9. The licensee is hereby authorized to possess byproduct material in theform of uranium waste tailings generated by the licensee's millingoperations authorized under SUA-1350.

10. Authorized place of use: The licensee's uranium milling facilitieslocated in Sweetwater County, Wyomiing.

11. For use in accordance with statements, representations, andconditions contained in Section 5 (including appendices), andsubsections 3.3.2, 3.3.4, 3.3.6, 3.3.7, 3.3.8, 4.3, 6.4, 7.3, 7.4and 7.5 and Table 4.1 of the licensee's revised application datedAugust 10, 1978,.and supplements dated October 31, 1973, andJanuary 24 and February 5, 1979. Whenever the word "will" is used inthe above mentioned sections, it shall denote a requirement.

12. The maximum mill throughput shall not exceed 3,200 lbs of barreled U308per day, averaged over a year.