Environmental Protection
Agency
Radiation
Office of
Radiation Programs
Washington DC 20460
EPA 520/4-80-011
December 1980
Draft
Environmental
Impact Statement
for Remedial Action
Standards for Inactive
Uranium Processing Sites
(40 CFR 192)

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                               EPA 520/4-80-011
               Draft
 Environmental Impact Statement
                for
    Remedial Action Standards
                for
Inactive Uranium Processing Sites
           (40 CFR 192)
            December 1980
        Office of Radiation Programs
       Environmental Protection Agency
          Washington, D.C. 20460

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                                  FOREWORD
(X)  Draft Environmental Statement
( )  Final Environmental Statement
                      Environmental Protection Agency
                        Office of Radiation Programs


1.  This Environmental Impact Statement was prepared by the Criteria and
Standards Division (CSD),  Office of Radiation Programs  (ORP),  U.S.
Environmental Protection Agency (EPA).

     Questions regarding this statement should be directed to  Stanley
Lichtman, Project Leader,  in care of the Director, Criteria &  Standards
Division, or at (703) 557-8927.

2.  EPA is proposing standards for the  disposal of uranium mill  tailings
from inactive processing sites, and for cleanup of land and buildings
contaminated by tailings.   EPA developed these standards pursuant to the
Uranium Mill Tailings Radiation Control Act of 1978 (PL 95-604).  The Act
requires EPA to set generally applicable standards to protect  the public
health, safety, and the environment from hazards posed by uranium mill
tailings at specific inactive processing sites.  The 25 sites  initially
designated are in Arizona, Colorado, Idaho, New Mexico, North  Dakota,
Oregon, Pennsylvania, Texas, Utah, and Wyoming.

3.  In developing a standard, EPA staff members meet with individuals and
organizations to seek both information and a thorough understanding of the
issues.  The staff then independently assesses the considerations specified
in EPA's Regulation EIS Procedures (39 F.R. 37419, October 21, 1974).

4.  This evaluation leads to the publication of a Draft Environmental
Impact Statement (DEIS), which is circulated to appropriate governmental
agencies for comment.  For this DEIS, EPA gained considerable  information
from the Draft Generic Environmental Impact Statement on Uranium Milling
(NUREG-0511) prepared by the U.S. Nuclear Regulatory Commission (NRC).
EPA has notified the public through the Federal Register that  the DEIS is
available, and has invited interested persons to comment on the draft
statement and the proposed standards.

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     Single  copies  of  this  statement may be  obtained  from:

         Director,  Criteria and Standards  Division
         Office  of  Radiation Programs  (ANR-460)
         U.S.  Environmental Protection Agency
         401 M Street,  S.W.
         Washington,  D.C.   20460


5.  After considering comments  on the  Draft  EIS,  EPA  will  prepare  a Final
EIS (FEIS) which will include a discussion of the concerns raised and the
conclusions  EPA reached.   EPA then will release  the Final  Environmental
Impact Statement.

6.  EPA has  asked the following Federal agencies to  comment on this
statement:

     Advisory Council on Historic Preservation
     Department of Agriculture
     Department of the Army, Corp of Engineers
     Department of Commerce
     Department of Energy
     Department of Health, Education & Welfare
     Department of Housing and'Urban Development
     Department of the Interior
     Department of Justice
     Department of Transportation
     Federal Energy Regulatory Commission
     Nuclear Regulatory Commission

     EPA also has sent copies  to all State Clearinghouses, to the American
Mining Congress  and to other individuals  and  organizations who have
notified EPA of their interest.

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                                  CONTENTS

                                                                       ~?aee
Foreword	•	      i

Contents	    iii

Tables	     vi

Figures	   viii

Summary	 .  .    S-l

1:  Introduction	    1-1

2:  Uranium Milling Operations  	    2-1
   .  2.1  History of Uranium Milling Operations  	    2-1
     2.2  Status of Milling Sites	    2-4
     2.3  The Inactive Sites	    2-6
         2.3.1  The Phase I Studies	    2-6
         2.3.2  The Phase II Studies	   2-18
     References for Chapter 2	   2-19

3:  Source Terms	    3-1
     3.1  Introduction	    3-1
     3.2  Radioactivity Source Terms  	    3-1
     3.3  Nonradioactive Contaminants   ..........  	    3-6
     3.4  Off-Site Contamination  	    3-9
     References for Chapter 3	   3-17

4:  Health Effects	    4-1
     4.1  Introduction	    4-1
     4.2  Radon and Its Immediate Decay Products ..........    4-4
     4.3  Estimates of the Lung Cancer  Risks  from  Inhaling  Radon
            Decay Products	    4-6
     4.4  Impact on Local and Regional  Population  from Radon
            Decay Products	   4-11
     4.5  Risks to the Continental  U.S. Population from Radon
            Emitted from Inactive Piles	   4-20
     4.6  Regional and National Effect  from Long Half-Life
            Radioactive Materials   	   4-23
     4.7  Impact from Gamma-Ray Exposure	   4-26
     4.8  Hazard from Water Contamination  .  .  ./	   4-30
         4.8.1  Introduction	   *-30
         4.8.2  Movement of Toxic Chemicals from Tailings	   4-33
         4.8.3  Toxicity of Major Toxic Substances
                  Found in Tailings	   4-36
     4.9  Conclusions	   ^-37
     References for Chapter 4	   4-40
                                     111

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5:  Alternative Tailings Disposal Control Levels ..........    5-1
     5.1  Introduction .......................    5_1
     5.2  Control of Radon-222 Releases  ......... '.*.'.'.*.    5-2
         5.2.1  Radon Control  ...................    5_3
         5.2.2  Effects of Radon Control on Release of
                  Airborne Particulates  ..............    5-6
         5.2.3  Effects of Radon Control on Direct
                  Gamma Radiation  .................    5_y
         5.2.4  Effects of Radon Control on Potential
                  Water Contamination  ...............    5_7
     5.3  Control of Surface and Ground Water Contamination  ....    5-9
     5.4  Longevity of Control ...................   5-,12
         5.4.1  Effects of Natural Forces  .......... ...   5-12
              5.4.1.1  Earthquakes .................   5-13
              5.4.1.2  Floods  ...................   5-14
              5.4.1.3  Windstorms and Tornadoes  ..........   5-14
              5.4.1.4  Glaciation  .................   5-14
         5.4.2  Effects of Human Activity  .............   5-15
     References for Chapter 5  ...................   5_17

6:  Monetary Costs and the Effects of Tailings Disposal  ......    6-1
     6.1  Estimated Costs   ....... ..............    6-1
     6.2  Estimated Health Benefits  ........ . .......    g_4
     6.3  Longevity of Controls   ........... . ......    g_g
     6.4  Environmental Impacts of Control Actions .........    6-9
     6.5  Occupational Hazards ................. t     6-10
     6.6  Local Economic Considerations at the Local Level .....   6-10
     References for Chapter 6  ...................   6-11

7:  Considerations for Cleanup of Contaminated
      Land and Buildings                                                 _1
     7.1  Introduction ................ t>              71
     7.2  Off-Site Contamination ............   ' * " '      y_i
     7.3  Potential Hazards of Off-Site Contamination  ..'!.'.'! .'    7-2
     7.4  Remedial Actions and Costs ........... * \ \ \      7.5
     7.5  Previous Standards for Indoor Radon
            Decay Product Concentration   ..............    7_7
     7.6  Normal Indoor Radon Decay Product Concentrations .....    7-8
     7.7  Practicality of Alternative Remedial
            Action Standards for Buildings .............   7-11
     References for Chapter 7  ............ 1111111   7-14

8:  Selecting the Proposed Standards ....... . ........    g_l
     8.1  Disposal Standards ........ ......  .1111!    8-1
         8.1.1  Radon Standard .............. !!!!."    8-2
         8.1.2  Ground Water Standard  ........ .111111    8-8
         8.1.3  Surface Water Protection  ........  .'.".'.*.".*   8-16
         8.1.4  Remedial Action for Existing Ground
                  Water Contamination  ...............   g_13
         8.1.5  Period of Application of  Disposal Standards  1 1 1 1   8-20
                                      v

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     8.2  Cleanup Standards  	   8-22
         8.2.1  Open Lands	   8-22
         8.2.2  Buildings	   8-25
              8.2.2.1  Indoor Radon Decay Product
                          Concentration Standards  	   8-25
              8.2.2.1  Standards for Indoor Gamma Radiation  ....   8-28
              8.2.2.3  Radiation Hazards not Associated
                         with Radium-226	   8-29
     References for Chapter 8	   8-31

9:  Implementation	    9-1
     9.1  Administrative Process	    9-1
         9.1.1  Disposal Standards  	    9-1
         9.1.2  Cleanup Standards   	    9-2
              9.1.2.1  Purpose of Cleanup Standards  	    9-2
     9.2  Exceptions	    9-3
     9.3  Effects of Implementing the Standards	• •    9-6
         9.3.1  Health	    9-6
         9.3.2  Environmental	    9-7
         9.3.3  Economic	    9-7
     9.4  The Proposed Standards	    9-9
     References for Chapter 9	   9-10


Appendix A - Comments and Responses to Comments (Reserved) 	    A-l

Appendix B - Development of Cost Estimates	    B-l

Appendix C - Toxicologies of Toxic Substances in Tailings  	    C-l

Appendix D - The Proposed Standards	    D-l

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                                   TABLES
                                                                      Page

2-1  Number of Active and Inactive Uranium Mill Sites  	      2-5

2-2  Inactive Mill Sites	    2-7,8

2-3  Summary of Conditions Noted at Time of Phase I
       Site Visits .	2-11,12

2-4  Summary of Phase I Findings and Principal Action
       to be Studied in Phase II	2-16,17

3-1  Radioactivity in Inactive Uranium Mill Tailings
       Piles	    3-2,3

3-2  Elements and Compounds Measured in an Inactive
       Tailings Pile	      3-7

3-3  Additional Elements and Compounds Found in
       Uranium Mill Tailings	      3-8

3-4  Elements/Compounds Reported in Elevated Concentrations
       in Ground Water in the Vicinity of Tailings Piles  	     3-10

3-5  Gamma Radiation Anomalies  and Causes   	  3-12,13,14

3-6  Contaminated Areas Around  Inactive Uranium Mill
       Tailings Piles   	   3-15,16

4-1  Estimated Effect on Local  and .Regional Populations
        from Exposure  to Radon Decay Products  from
       Tailings Piles   	  	  4-14,15,16

4-2   Individual Risk from Lifetime Exposure to Radon
       Decay Products  from Tailings Piles   	     4-18

4-3   Estimated Risk to Nearest  Residents  from Inhaling
       Radon Decay Products from Tailings  Piles	     4-19

 4-4   Risk from Background Radon in Residential Structures  ....      4-21

 4-5   Approximate  Contribution of Tailing  Piles at
        Inactive Sites to the National Health Risk from
        Radon Decay Products	      4-24

  -6  Summary Table — Tailings  Piles at Inactive Sites;
        Estimated National Risk  of Fatal Lung Cancer from
        Radon Emissions	»....     4-25
                                      VI

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4-7  Regional Impact from Uranium Mill Tailings  . .	   4-27

4-8  Increased Gamma Ray Dose Rates from Tailings
       Piles at Inactive Sites	   4-29

4-9  Estimated Lifetime Risk of Fatal Cancer from Total
       Body Gamma-ray Exposure at 100 mR/yr	   4-31

4-10 Estimated Risk of Serious Genetic Abnormalities ........   4-32

4-11 Summary — Risks from Radon Emitted from Tailings Piles
       at Inactive Sites	   4-39

5-1  Nominal Half-Value-Layers of Typical Natural Materials
       for Reducing Radon Releases 	    5-4

6-1  Ranges of Estimated Costs by Disposal Option and
       Radon Control Level	    6-3

6-2  General Post-Disposal Benefits of Disposal Options  ......    6-7

7-1  Average Annual Radon Decay Product Concentrations in
       Normal Buildings   	  .....   7-10

7-2  Experience with Grand Junction Remedial Action Program  ....   7-12
                                     VII

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                                  FIGURES

                                                                       Page

4-1  Uranium-238 Decay Series  	  ........     4-2

4-2  Lung Cancers as  a Function of Cumulative WL  Months	     4-7

5-1  Percentage of Radon Penetrating a Cover 	     5-5

5-2  Percentage of Gamma Radiation Penetrating  a
       Cover	     5-8
                                     viii

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                                  SUMMARY








     The Environmental Protection Agency (EPA) is proposing standards for




disposing of uranium mill tailings from inactive processing sites and for



cleaning up contaminated open land and buildings.  These standards were




developed pursuant to the Uranium Mill Tailings Radiation Control Act of




1978 (Public Law 95-604).  This Act requires EPA to promulgate standards




that can be generally applied to protect the environment and the public




health and safety from radioactive and nonradioactive hazards posed by




uranium mill tailings at designated inactive processing sites.  The 25




presently designated sites are inactive uranium mill tailings piles in the




States of Arizona, Colorado, Idaho, New Mexico, North Dakota, Oregon,




Texas, Utah, and Wyoming and at the location of a former rare-metals plant




in Pennsylvania.








1.  The Proposed Standards Cover Two Situations



     a.  Disposal of Tailings:



     The standards limit release of radon gas  to the air from disposed



tailings to 2 picocuries per square meter per  second (pCi/m2-sec), about




twice the average of normal soils.  When the radon  from a  cover  of normal



soil is added to that allowed from tailings, the resulting release will



still be within a normal range of variation.   The standards  restrict con-



tamination of drinkable ground water to preserve its potability.  Lower



quality but potentially useful ground water and  all surface  waters are




protected against degradation.  The standards  also  require a reasonable



expectation that  the  disposal methods will be  effective  for  at  least one



thousand years.

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     b.  Cleanup of Contaminated Open Land and Buildings:



     The standards require cleanup of open land contaminated by tailings




when the average radium concentration attributable to tailings exceeds 5




picocuries per gram (pCi/gm).  Five pCi/gm is three to five times the




average radium concentration in normal U.S. soil.  Soil contaminated by



tailings, however, usually lies in a thin layer on the surface, while the




radium in normal soil occurs throughout its full thickness.  Radiation



from land that satisfies the standard will be within the normal variations



among undisturbed land areas.








2.  Summary of Environmental Impacts




     EPA estimates that implementing the disposal standards at all



designated sites would prevent  about 200 premature deaths  per century  from



radiation-induced  lung cancer for as long  as  the  standards apply.  We




further  require  a  reasonable expectation  that the standards will be




satisfied for at least one  thousand years.  About 140  of the  200 deaths



would  be expected  in the  populations within 50 miles  of  the  inactive




 tailings piles  and the rest  in  the remaining  continental U.S. population.




Health effects  from contaminated ground water are not included  in  the



 above  estimate.








      Estimates  of  health  improvements  from implementing  the  cleanup




 standards have not been made.   Such benefits would  include not only pre-




 venting adverse health effects, but  also  reclaiming contaminated lands



 currently unfit for unrestricted use.
                                      S-2

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     We have estimated the costs of implementing the standards.  For an




average inactive uranium mill tailings pile, meeting the disposal standard




will cost from 1 million (1978) dollars to over 13 million (1978) dollars,




depending on the methods used.  In a previous cleanup program for buildings




authorized by Congress in 1972 under PL 92-314, cleanup cost about 13,500




(1978) dollars for a residential structure and about 38,500 (1978) dollars




for a commercial building.  The probable total cost of the cleanup and




disposal programs under PL 95-604 will be 200 million (1978) dollars to




300 million (1978) dollars.  These expenditures could benefit the local




economies, and should have no perceptible effect on the national economy.









3«  Alternat iyes Considered




     With regard to the form and content of the standards, we considered




the following major alternatives:









     a.  Disposal Standards:




     Uncontrolled uranium mill tailings endanger people and the




environment —









     o   By releasing radon-222, a radioactive gas, into the atmosphere,




         where it and its radioactive decay products can be breathed;








     o   By supplying a source of windblown radioactive particles;








     o   By exposing people who live or work near the tailings to direct




         gamma radiation;  and






                                    S-3

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     o   By releasing radioactive and nonradioactive contaminants to



         surface or ground water through erosion or leaching.








     Generally applicable standards to protect the environment and the




public's health and safety must be based on the reasonableness and feasi-



bility of controlling these potential hazards.  Because of the long




lifetimes of the radioactive contaminants and the presence of  such perma-



nently toxic nonradioactive contaminants as arsenic and lead in tailings




material, the longevity or permanence of control methods must  be



considered.








     The principal health hazard is release of radon-222 into the




atmosphere.  We conclude  that  techniques which control radon releases




reasonably well and have  lasting effectiveness will essentially control




airborne particles and direct  gamma radiation  completely.  The standards,




therefore, do not specifically address  these letter two hazards,  and  the



following  discussion of control  alternatives  is  restricted to radon-222




releases and water.   This  section  also  discusses alternative  longevity



requirements  for controls.








 (1)   Radon Control




      We  considered alternatives  for  limiting  radon that ranged from no




 control  (the  existing condition) to  essentially complete  control  (pre-




venting  almost  all radon  release). We  also explored   middle  alternatives



 to control radon release  to various  degrees down to about the normal
                                     S-4

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background level.  We compared all three alternatives for costs, benefits,




feasibility,  longevity,  and other factors.








     We rejected the concept of no control, because people living near




uncontrolled  piles would clearly have a higher risk of radiation exposure.



Radon emissions, moreover, would convey a health hazard over long



distances and for long periods.








     We rejected the concept of essentially complete radon control, because




it may be impractical and would provide a small added reduction in overall




risk at relatively high cost.








     The proposed disposal standards, therefore, limit radon releases from



tailings piles to be within the range of variation found in normal soils.








(2)  Water Contamination




     Alternatives for limiting water contamination range from no



additional control (the existing condition) to complete prevention.  We




examined these and a middle ground: limiting contamination to a degree




comparable to other water quality programs.








     We concluded that some control is warranted.  The potential effects



of uranium mill tailings on surface and ground water quality vary




considerably  from site to site, and under some conditions ground water



could become  unusable over an area much larger than the pile.  The




likelihood that this will happen has not been thoroughly examined.






                                     S-5

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     Available information suggests that special measures to protect



ground water often will be unnecessary.  Where the standards might be



exceeded only immediately near a pile, moreover, we believe that the



substantial disruptions and cost needed to avoid the violation would be



unwarranted.








     We therefore propose to apply ground water standards only within one



kilometer from the pile when an existing site is used for disposal, and



within 0.1 kilometer at new disposal sites.








     The standards provide that tailings disposal will not cause ground



water contaminants to exceed specified levels.  If the ground water



already exceeds these levels for reasons other than tailings, no further



degradation is allowed.  Where ground water contamination has already



occurred, it may sometimes be possible to reduce it, but requiring remedial



actions to satisfy pre-set standards in every case is not practical.  The



proposed ground water standards therefore do not apply to materials



already released from the tailings.  Using their authorities under



PL 95-604, however, we expect other Federal agencies to  take practical



actions at sites where they are needed to avoid harm from such materials.








     The radon release and ground water protection standards should protect




surface water adequately.  As assurance, however, we propose to require



that surface water not be degraded by  tailings after disposal of the piles.
                                     S-6

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(3)  Length and effectiveness of controls




     The health protection the disposal system ultimately affords depends




on the degree of control and the time over which control is maintained.




Requirements could range from a few years to as long as the tailings



remain potentially hazardous.  We considered the technical and economic



aspects of various control periods.








     Congress recognized that uranium mill tailings represent long-term



hazards, and directed EPA to set reasonable standards for their long-term



disposal.  We propose to require a reasonable expectation that the radon




emission and water protection standards for tailings disposal will be




satisfied for at least one thousand years.  Institutional controls, such




as record keeping, maintenance, and land-use restrictions, can provide



greater protection than the standards require, but they are unreliable as



the primary control over one thousand years.  Though institutional




controls can be helpful, physical disposal methods are necessary.








     Pragmatism suggests the choice of a thousand-year period, though




technically and economically reasonable disposal methods may, for some



tailings piles, afford even longer protection.  A thousand-year standard




reflects our judgment that the disposal standards must be practical for



all the inactive sites.  It does not mean that we care little for the



future beyond one thousand years.
                                    S-7

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     b.   Cleanup Standards:



     Uranium mill tailings  from inactive sites have been spread near and




far by wind, water, and people.  Therefore, standards for cleanup must




address  the following situations:








     o   Tailings have spread different distances from different piles,



are found at various depths in the soil, and are mixed with various




materials.  The standards must therefore specify the quantity or



concentration of tailings which  requires cleanup.








     o   Radioactive elements leach out of tailings piles into the subsoil




beneath.   The standards must  therefore  specify the  permissible  level  of




radioactivity in the subsoil, should the pile covering  it be removed.








      o    Tailings  used a landfill  or made  into building materials  or  which




accumulate around  a  structure are  particularly hazardous.  The  exchange  of




air between a building's interior  and  the  outdoors  is limited,  so  indoor




concentrations  of  radon decay products  may be many  times the outdoor




 levels.   The standard must  therefore  specify the maximum allowable concen-




 tration of radon decay products  inside  buildings.   The cleanup standard




 for open land must consider the possibility of future construction.








      The level  of radon decay products in a building is related, among




 other things, to the concentration of radium, present naturally or as a




 contaminant, in the underlying or adjacent soil.  So many other factors



 arise, however ~ the rate at which air is exchanged between indoors  and






                                      S-8

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outdoors, for example — that strictly correlating the interior level with




the radium in the soil is difficult.  Radium concentrations from 1 to



5 pCi/gm in soil, a range whose lower end is common among natural soils,




can produce indoor levels of radon decay products greater than 0.01 WL.








     Natural or contaminated soils with radium concentrations of 5 pCi/gm




through a depth of several feet can also produce gamma radiation exposure



rates of about 80 mR/yr.  Exposure rates are proportionately higher or




lower for other radium concentrations, decreasing as the layer of radium-



containing material becomes thinner or is covered over by other materials.








     The proposed standard requires that for any open land contaminated




with tailings, the average radium concentration in any five-centimeters-




thick layer within one foot of the surface, or any 15 cm layer below one




foot, shall not be more than 5 pCi/gm after cleanup.  The proposed standard




is EPA1s judgment of the most stringent cleanup condition that may reason-



ably be required for all the inactive mill sites.  After the required




cleanup, radon emission and gamma radiation from the site will be within



the normal variations that occur among nearby undisturbed land areas.








     Exposure even to normal concentrations of indoor radon decay products



carries some health risk, but we believe Congress intended that tailings



should not unreasonably increase this risk.  Concentrations of indoor radon



decay products in normal buildings, however, vary widely, and depend on




many factors.  Of the alternative forms for a remedial action standard for



indoor radon decay products, we decided that limiting the total






                                     S-9

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concentration is the only workable form.  We believe that the proposed




remedial action level of 0.015 WL (including background)  for occupied or




occupiable buildings is the most protective level that can be justified.




Experience in a cleanup program in Grand Junction,  Colorado, and studies




performed by EPA for homes in Florida indicate that remedying concentra-




tions greater than 0.015 WL usually is practical.  We have concluded from




studies of radon decay product concentrations in normal houses that efforts




to reduce levels significantly below 0.015 WL by removing tailings would




often be unfruitful and would waste the money spent.









     The proposed limit is based on the hazard from breathing indoor air




containing radon decay products.  Gamma radiation, however, can penetrate




the body from the outside.  We expect that the indoor radon decay product




standards generally will be met by removing  tailings from under and around




the building; this will eliminate any indoor gamma radiation problem.  For




some buildings, however, removing the tailings may be impractical, more




for engineering reasons than because of cost.  Cleaning the air, improving




ventilation, and sealing the walls and  floors are alternatives, but if




these methods are used, standards will be needed to limit the occupants'



exposure  to  gamma radiation.









     If the  gamma radiation standard is too  lenient, methods other than




removal of tailings  could  be  used more  often.  Because removal  is defini-




tive and  its effectiveness long  lasting, however, it is the remedial




method  we wish  most  to encourage.  To  this  end,  our  proposed  action  level




for  gamma radiation,  0.02 mR/hr  above background, allows some limited






                                     S-10

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flexibility in the methods chosen to reduce indoor radon decay product




concentrations.  Reducing the standard much below 0.02 mR/hr would




virtually eliminate this flexibility and provide only a small additional




health benefit to a few individuals.








     The proposed standards will be implemented by the Department of




Energy, with the concurrence of the Nuclear Regulatory Commission and in




cooperation with other Federal agencies, affected States, and Indian




tribes.  Because the proposed standards probably will not fit exceptional




circumstances, we have provided criteria for determining when exceptions




to the standards are justified.  In such cases, DOE, with the concurrence




of NRC, may select and perform remedial actions which come as close to




meeting the standards as is reasonable.
                                    S-ll

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                              1:  INTRODUCTION









     In Public Law 95-604, the Uranium Mill Tailings Radiation Control Act




of 1978 (42 USC 7901),  the Congress found that uranium mill tailings at




active and inactive mill operations may pose a potential and significant




radiation health hazard to the public,  and that every reasonable effort




should therefore be made to stabilize, control, and dispose of such




tailings in a safe and  environmentally sound manner to prevent or minimize




radon diffusion into the environment and other environmental hazards from




tailings.








     The Act specifically calls for EPA to set generally applicable




standards for both radiological and nonradiological hazards posed by




"residual radioactive materials" at certain inactive uranium mill tailings




sites and at other sites where such materials are deposited.  "Residual




radioactive material" is (1) tailings waste remaining after uranium and




other products are extracted from ore and judged radioactive by the




Secretary of Energy, and (2) other waste connected with the extraction



process, including unprocessed ore and low-grade material, judged




radioactive by the Secretary of Energy.








     The Act also requires EPA to set generally applicable standards for




active uranium mill and disp'osal sites.  The standard discussed in this




Environmental Impact Statement does not address active sites.  We will




propose such a standard later.  Our current proposal sets standards for




cleaning up open lands and structures contaminated with residual

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radioactive material — mainly tailings or similarly hazardous wastes —

control; and for controlling uranium mill tailings from inactive

processing sites for a long time.



     The Uranium Mill Tailings Radiation Control Act of 1978 (PL 95-604)

names 22 inactive processing sites.  Twenty-one are inactive uranium mill

sites in the western United States, and the other is the location of a

former  rare-metals  processing plant in Canonsburg, Pa.  This Environmental

Impact  Statement primarily applies to the mill sites but also addresses

the Canonsburg  site,  for  its potential hazards and many of  the methods  to

correct and control them  parallel those of the other sites.1



      In developing  the proposed  standards, we  first evaluated  the potential

effects on public health  and the environment of tailings at the designated

sites.  We then reviewed  general approaches  to controlling  these  effects

and developed cost  estimates for specific  control methods.  Our proposed

control standards were based on  such  factors  as  improved health;  longevity

of control methods; limitations  of  institutional  cost;  feasibility,  and

 the potential  impact of the control methods  themselves.  Under PL 95-604,
 1 The Department of Energy formally designated the 22 sites in accord
 with Sec. 102 of PL 95-604.  It also has identified and designated three
 other processing sites that require remedial action.  These are located
 near Bowman and Belfield, North Dakota, and Baggs, Wyoming.  These three
 sites have only recently been studied, and they appear to be among the
 least hazardous in the entire group (see "Uranium Mill Tailings Site Visit
 and Preliminary Health Impact Evaluation," a report prepared by Ford,
 Bacon and Davis Utah, Inc., October 17, 1979).  Data on them is much less
 complete than for the other designated sites, so we have omitted them from
 our analysis.  We believe that their omission has little effect on our
 conclusions.
                                      1-2

-------
the Department of Energy, the affected States, and the Nuclear Regulatory




Commission are responsible for implementing the standards.








     In this Draft EIS, Chapter 2 summarizes the history of the uranium




milling industry and briefly surveys the designated sites.   Chapter 3



reviews their radiological and nonradiological characteristics and




discusses off-site contamination of nearby land and buildings.   Chapter 4




outlines the potential health hazards posed by uranium mill tailings with




estimates of the risks to people living nearby, in the region,  and in the




continental United States.  Chapter 5 examines alternative degrees of




control.  Chapter 6 presents monetary cost estimates for various




engineering approaches and discusses such other significant control




factors as duration, effectiveness, and occupational hazards.  Chapter 7




addresses off-site contamination and factors weighed in cleaning up




contaminated land and structures.  Chapter 8 explains how we chose the




proposed standards.  Chapter 9 discusses the process of implementing the




standards, and the anticipated effects.
                                     1-3

-------
                       2:   URANIUM MILLING OPERATIONS




2.1  History of Uranium Milling Operations




     A brief history of uranium milling appeared in the Nuclear Regulatory




Commission's Draft Generic Environmental Impact Statement (NR 79).  The




history summarized two papers by Merritt (ME 71) and Facer (FA 76) and,




for its relevance to this report, is repeated here.








         In the past 35 years the uranium industry has undergone a series




         of transformations, the element changing almost overnight from a




         commodity of only minor commercial interest to one vital for




         nuclear weapons and, now, to its important peaceful use as a  fuel




         for generation of electrical energy.  With each change there has




         been a surge of interest in ore exploration and development,  and




         in new and expanded production facilities.









         The military demand for uranium beginning  in  the early 1940s  had




         to be met from known sources of supply.  The  rich pitchblende




         ores of the Shinkolobwe deposit in the Belgian Congo and the



         Great Bear Lake deposit in Canada supplied uranium during the war




         years and were supplemented by production  from treatment of old




         tailings dumps and a few small mines in the Colorado Plateau



         area*  These high-grade ores and  concentrates were refined by an




         ether extraction technique adapted from analytical procedures.




         Crude ore milling  processes for  low-grade  ores used during this




         period reflected little change from methods used 40 years earlier




          (at  the  turn of  the last  century) with uranium recovery  from  the

-------
leach solutions  based on several  stages  of  selective




precipitation.  Milling costs were high and overall recovery was




low, as judged by current standards.








With passage of the Atomic Energy Act of 1946, a strong emphasis




was placed on the discovery and development of new worldwide




sources of uranium.  At the same time, the research efforts begun




earlier were expanded in scope and magnitude to advance the




process technology.  These efforts led to greater use of lower




grade ores than previously had been considered feasible, such as




the uranium-bearing gold ores in South Africa, as a source of




uranium, and to the discovery and developemnt of large, low-grade




deposit in the Beaverlodge, Elliot Lake, and Bancroft regions of




Canada.









In  the United States, prospecting and mining for uranium were




encouraged by the Atomic Energy Commission  (AEC) through




guaranteed fixed prices for ore, bonuses, haulage allowances,




establishment of ore-buying stations  and access roads,  and other




forms  of assistance.  These incentives led directly to  an




increase  in  the  known mineable reserves of  ore  in  the western




United States from about  9 x  105 metric tons  (MT)  (1 x  106




short  tons (ST)> in  1946  to 8.1 x  10? MT (8.9 x 107 ST) in




 1959.   Programs  also were initiated  to  examine  other possible




sources of uranium and  to develop methods  for processing  these




materials.   AEC purchases from 1948  through 1970  totalled






                            2-2

-------
approximately 3 x 105 MT (3.3 x 105 ST) of U30g  of wh£ch




nearly 1.6 x 105 MT (1.8 x 105 ST) with a value of about




$3 billion were supplied from domestic sources.









During the peak production years in the United States, from 1960



through 1962, the number of operating mills (excluding plants




producing by-product uranium from phosphates) varied from 24 to




26, with total annual production exceeding 1.5 x 104 MT




(1.7 x 104 ST) of U30g from the treatment of about



7 x 106 MT (8 x 106 ST) of ore.








In 1957, it was apparent that very large ore reserves had been




developed, and that additional contracts, which were the main




incentive for exploration by potential producers, would lead to




commitments exceeding government requirements through 1966.  In




1958, the AEC withdrew its offer to purchase uranium  from any ore




reserves developed in the future.  This led to shutdowns of mills




after expiration of contracts and to stretching out of deliveries




under long-term contracts in the United States, Canada, and South




Africa.









Total production of U30g through 1977 from U.S. sources is



estimated at about 2.7 x 105 MT (3 x 105 ST).  The amounts of




ore used in the production of this U30gj flnd the approximate




amount of tailings produced, were expected to reach 1.3 x 108




MT (1.4 x 108 ST) by the end of 1977.  Of this total, about






                            2-3

-------
         20%,  or  2.3 x  107 MT  (2.5 x  107  ST),  is  located  at  inactive




         mill sites and the  balance  (80%) is located at currently active




         mill sites.









     Nuclear power's growth  in the 1970's and  projections of the  future




need for nuclear fuel  spurred increased exploration for ore and




construction of mills  in the last part of the  decade.








2.2  Status of Milling Sites




     Table 2-1 shows the number of active and inactive uranium milling




sites in the United States at five-year  intervals.  This listing omits




several pilot facilities that produced uranium before 1950.









     The hazards posed by mill tailings  were  incompletely recognized in the




uranium industry's early years,  and, while  the Atomic Energy Act of 1954




instituted  licensing of mill  operators,  tailings  remained free of controls.




Numerous studies have assessed tailings  hazards,  and several State and




Federal agencies — Colorado's,  for  example — have acknowledged a need for




controls.   But no  comprehensive  program  to  control tailings began until




 after the  Subcommittee on Raw Materials  of  the  Joint Committee on Atomic




Energy conducted Congressional hearings  in  1974.   Studies supported by the




Energy Research and Development  Administration  (later  merged into  the




Department  of Energy)  then  followed. The first  set of studies (the Phase




 I studies)  determined  the current status and  general  scope  of the hazards




 at inactive mill tailings sites. The second  set (the  Phase II studies)
                                     2-4

-------
                               TABLE 2-1
           Number of Active and Inactive Uranium Mill Sites
                                                           (a)
Year No.
Up thru 1940
1945
1950
1955
1960
1965
1970
1975
1980 (Jan)
of Active Sites
4
5
9
12
30
21
15
15
2Kb)
No. of Inactive Sites
0
1
1
2
4
13
20
24
25
Total
4
6
10
14
34
34
35
39
46(b)
     References JO 77, AU 70, and TH 79.

    included are 8 solution mining operations,  4 phosphoric acid
by-product plants, and 4 heap leaching operations.
                                 2-5

-------
assessed them in greater detail and discussed various alternatives for




controlling them.








2.3  The Inactive Sites




     The Congressional hearings noted above took place on March 12,



1974.  The bills discussed, S.2566 and H.R. 11378, were identical.  They




proposed that the U.S. Atomic Energy Commission (later the Energy Research




and Development Administration and now the Department of Energy) and the




State of Utah jointly assess and act appropriately to limit people's



exposure to radiation originating from the Vitro uranium mill  tailings




site at Salt Lake City, Utah.








         EPA endorsed  the bills' objectives but, with AEC, recommended




instead that the  two agencies,  in cooperation with  the  states, assemble




comprehensive studies  of all  inactive mill sites.   The  studies would be




divided into two  phases.   The Phase  I  studies would establish the sites'




condition,  ownership,  surroundings,  and  the need, if any, for  more



detailed studies.   The Phase II studies  would, as needed, evaluate the




hazards and analyze alternative  solutions  and their costs.  Congress




 accepted the  proposal, and in May  1974 the Phase I  studies  began.








 2'3-1   The Phase  I  Studies




          The Phase  I studies conducted during 1974  summarized conditions




 at 21  inactive uranium milling sites (See Table 2-2) and outlined the




 detailed engineering assessments to  be performed in Phase II.
                                      2-6

-------
                                 TABLE 2-2

                            Inactive Mill Sites


1.
2.

3.
4.
5.
6.
7.
8.
9.
10.
11.

12.

13.
14.

15.
16.

17.

18.

Site
ARIZONA
Monument Valley
Tuba City
COLORADO
Durango
Grand Junction
Gunnison
Maybe 11
Naturita
New Rifle
Old Rifle
Slick Rock (NC Site)
Slick Rock (UC Site)
IDAHO
Lowman
NEW MEXICO
Ambrosia Lake
Shiprock
NORTH DAKOTA
Belfield
Bowman
OREGON
Lakeview
PENNSYLVANIA
Canonsburg (a)
SOUTH DAKOTA
Phase I

X
X

X
X
X
X
X
X
X
X
X

X

X
X




X



Phase II

X
X

X
X
X
X
X
X
X
X
X

X

X
X




X

x(b)

Designated under
PL 95-604

X
X

X
X
X
X
X
X
X
X
X

X

X
X

X
X

X

X

    TEXAS
20. Falls City                      x
21. Ray Point                       x
                                                               (continued)
                                     2-7

-------
                                TABLE 2-2 (continued)

                            Inactive Mill Sites
                                                       Designated under
        Site                      Phase I    Phase II     PL 95-604

22.
23.
24.
25.
26.

27.
28.
29.
UTAH
Green River
Hite(e)
Mexican Hat
Monticello (f)
Salt Lake City
WYOMING
Baggs
Converse County
Riverton

X
X
X
X
X


X
X

X
X
X
X
X


X
X

X
X
X
X
X

X
X
X
                     Totals        21           23              25


    (a)  Former rare-metals plant;   not  an inactive  uranium mill  site
    (b)  Study done as part of Formerly  Utilized MED/AEC Sites Remedial
Action Program
    (c)  Owned by TVA
    (d)  Uranium not sold to U.S. Government
    
-------
         The Phase I studies excluded several sites:   Monticello,  Utah




(owned by the Department of Energy);  Edgemont, South Dakota (owned by




the Tennessee Valley Authority);  Kite,  Utah (covered  by Lake Powell,  a




lake created by the 1963 construction of the Glen Canyon Dam after




high-grade tailings were removed from the site);  Riverton,  Wyoming




(licensed by the AEC to a private owner at the time of the Phase I




studies but later added to the Phase II studies);  and Bowman and




Belfield, North  Dakota, Baggs, Wyoming, and Canonsburg, Pennsylvania.








     As a sample of the Phase I studies, the following excerpts from the




Phase I Summary discuss the Vitro site at Salt lake City, and




stabilization, off-site radiation,  and the use made of inactive mill




sites.








         The Vitro Sitej, Salt Lake  City




         The existing conditions at the Vitro site in Salt Lake City are




         completely unsastisfactory.  The tailings pile, located at the




         center of population of Salt Lake valley, is largely uncovered




         and subject to continuing  wind and water erosion.   While the




         extent of exposure of the  population to radiation from this




         source may be difficult to quantify, the spread of radioactivity




         is readily detectable for  considerable distances offsite.




         Because of the continued industrial growth in the  area, the




         population exposure can be expected to increase.  The site is




         only partially fenced and  is readily accessible to the public.




         If the tailings pile were  to be stabilized by covering and






                                     2-9

-------
vegetation at the present site, their integrity would be




difficult to maintain.  While contamination of surroundings from




blowing dust could be reasonably well controlled, the emanation




of radon gas and leaching of radium into ground waters would be




expected to continue.  The representative of AEC, EPA and  the




State of Utah concur that the present site is unsuited to




long-term  radioactive  tailings  storage,  and  the  Phase II study of




the  Vitro  site should be directed principally toward a plan for




removal  to a more  suitable  location.









 Stabilization




 The  conditions  found at  the 21 mill sites  are summarized  in




 (Table 2-3).   Tailings stabilization at six sites had not been




 attempted at all.   However, following the  site visit,  the State




 of Oregon notified the owner that stabilization should be under-




 taken as soon as possible at Lakeview.  The chemical surface




 coating used at Tuba City, Arizona, has broken up after only a




 few years weathering and is considered unsuccessful.  The




 conditions at Shiprock, New Mexico, on  the Navajo Reservation




 have been considerably aggravated as a result of the operation of




 a heavy earth-moving-equipment school  on  the  site.  The State of




 Colorado  adopted  regulations  in  1966  for stabilization and control




  of  uranium mill tailings  by the mill  owners.   The  substantial




  efforts made in that  state  have  been  fairly successful.   In  no




  case,  however,  was it found that the results could be  considered




  entirely satisfactory.   Some erosion and  loss of cover was noted






                             2-10

-------
              TABLE 2-3




SUMMARY OF CONDITIONS NOTED AT TIME OF
Condition
of
Tailings
ARIZONA
Monument Valley
Tuba City
COLORADO
Durango
Grand Junction
Cunnison
Maybell
Katurita (a)
Nev Rifle
Old Rifle
Slick Rock (NC)
Slick Rock (DC)
IDAHO
Lowman
NEW MEXICO
Ambrosia Lake
Shiprock
OREGON
Lakeview
PENNSYLVANIA
Canonsburglb )
TEXAS
Falls City
Ray Point
UTAH
Green River
Mexican Hat
Salt Lake City
WYOMING
Converse City


U
H

P
S
S
S
S
P
S
S
S

U

0
P

V

U

P
P

S
U
U

U

Condition of
Buildings
& Structures
on Millsite

R
PR-UO

PR-UO
PR-0
B-0
R
PR-0
M-0
PR-OU
R
R

R

PR-0
PR-0

M-OU

B-O

M-OU
M-OU

B-O
B-O
R

R

Mill
Housing

N
E-0

N
N
N
N
E-P
N
N
N
E-P

N

N
E-0

N

N

N
N

N
E-0
N

N


PHASE I
Adequate Property
Fencing, Bounded by
Posting, & River or
Surveillance Stream

No
No

Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes

No

Yes
Yes

Yes



Yes
Yes

Yes
No
No

No


No
No

Yes
Yes
No
No
Yes
Yes
Yes
Yes
Yes

Yes

No
Yes

Ho

Yes

No
No

No
No
Yes

No

SITE VISITS
Dwellings &/or
Industry
Within 1/2
Mile

Yes
Yes

Yes
Yes
Yes
No
No
Yes
Yes
Yes
Yes

Yes

No
Yes

Yes

Yes

No
No

Yes
Yes
Yes

No

Possible Tailings
Visual Evidence Ground &/or Removed From Other
Wind &/or Water Surface Water Site for Hazards
Erosion Contamination Private Use On-Site

No
Yes

Yes
No
No
No
Yes
Yes
No
Yes
No

No

Yes
No

Yes

Yes

No
No

Yes
Yes
Yes

No


No
No

No
No
Yes
No
Yes
Yes
Yes
No
No

No

No
No

No


No
No

Yes
Yes
No
No
No
No
Yes
No
No

Yes

No
Yes

No


No
Yes

Yes
No
No
No
No
No
No
No
No

No

No
Yes

No

Unknown No

Yes
No

Yes
Yes
Yes

No


No
No

No
No
Yes

No


No
No

No
No
Yes

No
(Continued)

-------
                                                                                TABLE 2-3 (continued)

            Column  1.  S - Stabilized, but  requires  improvement     Column  2.  M - Mill  intact                               Column  .    -  one
                       P - Partially stabilized                                B - Building(s) intact                                   E - "astiag
                       U - UnstabilUed                                        * - «"!  ^d/or buildingB removed                        O - Occupxed
                                                                              PR - Hill  and/or buildings partially removed              P - Part occupied
                                                                                0 - Occupied or used
                                                                               00 - Unoccupied or unused


             (*)  Pile moved  to new location after this study.
            (b)  Sot in Phase I, but information included for completeness
ro
i—1
ro

-------
in all cases,  and the vegetation was generally not self-sustaining




without continued maintenance, usually including watering and




fertilization.  Thus, the stabilization work done to date




represents a holding action, sufficient for the present, but not




a satisfactory answer for long-term storage.









Offsite Radiation




The mechanisms known to cause spread of radioactivity from the




sites are:




1.   Windblown solids.




2.   Radon gas and its decay products.




3.   Deliberate removal of tailings and other materials for




     offsite use.




4.   Water erosion and dissolution.




5.   Ground water and soil contamination.









In addition, low grade ores and mine wastes have occasionally




been spilled or dumped offsite.








Evidence exists of all these mechanisms causing some degree of




increase in radioactivity above natural background.  In no other




location was there evidence of the widespread use of tailings in




building construction such as occurred in Grand Junction,




Colorado,  Nevertheless, there are some habitable structures in




several other  locations where tailings use  is suspected.
                           2-13

-------
Measurements of dust concentrations in air made near tailings




piles in the past have not indicated significant hazard from




inhalation.  However, the significance of blowing dusts settling




out in the general vicinity over a period of many years has not




been thoroughly evaluated.








The EPA has held the position for some time that radon gas




emanating  from a tailings pile may cause a detectable  increase  in




airborne radiation levels in the vicinity of a tailings pile,



roughly within half  a mile.  The gas will diffuse readily  into




existing structures, but its particulate decay products would



tend  to .remain inside,  possibly causing  a buildup in radioactivity




within the structure.   There is little data available  to support




this  hypothesis, but it needs  to be  checked carefully, as  it could




have  significant bearing on decisions regarding  removal of




tailings  piles from populous areas.  High radon  decay product




levels were found  in structures close to the Vitro  pile, but the




possibility of their having been built  over  tailings has not been



excluded.









Water erosion does not  appear  to have been a  significant factor



 in the off site  migration of  tailings.   However, the movement of




 radium and soluble salts into  the  sub-soil  in areas with high




 water table needs further evaluation.   In a few locations  tailings




 piles are located near water  courses where  flooding can be a



 problem.






                            2-14

-------
         Use of Mill Sites




         Where housing and other structures remain from the milling opera-




         tions they have been frequently put to use.  Housing at Tuba City,




         Naturita, Slick Rock, Shiprock and Mexican Hat is occupied.



         Buildings on the mill sites at Gunnison, Naturita, Shiprock, Green




         River and Mexican Hat are being used for warehousing, schools and



         other purposes.  At several sites, buildings are still used for




         company activities.  At Salt Lake City a sewage disposal plant is



         operating on the site.  Construction of an automobile race track




         was begun in the middle of the tailings pile.  It was subsequently




         stopped by the State upon recommendations of AEC and EPA.  The




         pressure for use of sites in urban areas is likely to increase



         with time consistent with projected population growth.  None of




         the areas formerly occupied by milling facilities, ore stockpiles,



         etc., have been examined to determine the depth of soil contamin-




         ation, or suitability for future unrestricted use.








    Table 2-3 summarizes the widely varying conditions at the time of the



Phase I site visits (AE 74, Table I).  Table 2-4 summarizes the Phase I




studies and presents the recommendations made for Phase II studies of




potential remedies for each site (AE 74, Table II).








    Since the Phase I studies, the Naturita pile has been moved and the




Shiprock site has been cleaned up and the pile stability improved.



Tailings from the Monument Valley, Falls City, and Ray Point sites have




been removed and used as construction material.   At  some sites buildings






                                    2-15

-------
                                                                                      TABLE ?-4

                                                      SUMMARY OF PHASE I FINDINGS AND PRINCIPAL ACTION TO  BE STUDIED IN PHASE II
ro
 Arizona
   Monument Valley
   Tuba City

  Colorado
   Durango
   Grand Junction
   Gunnison
   Maybell
   Naturita
   New  Rifle
   Old  Rifle
   Slick Rock  (NC)
   Slick Rock  (DC)

Idaho
   Lawman

Hew Mexico
   Ambrosia Lake
   SMprock

Oregon
   Lakeview

Texas
   Falls City
   Ray Point
                                    Years Operated
                                     1955-67
                                     1956-66
1943-63
1951-70
1958-62
1957-6A
1939-63
1958-72
1924-58
1931-43
1957-61
                                    1955-60
                                    1958-63
                                    1954-68
                                    1958-60
                                    1961-73
                                    1970-73

Tons of Tai lines
(in thousands)
1,200
800
1,555
1,900
540
2,600
704
2,700
350
37
350
90
2,600
1,500
130
2,500
490
AS DETERMINED BY AEC
Ra in Ci I

50
670
1 , 200 X
1,350 X
200 X
640
490
2,130 X
320 X
30
70
10
1,520
950 X
50
1,020
230
(NOW DOE)
IX


X
X
X
X
X
X

X
X
X
X
K
X
X
X
X

III IV V

X
XXX
X X
X X
X
X
X
X
X X

X
X
X X
X X
X X



VI

X



X


X
X








                                                                                                                                         VII
                                                                                                    X
                                                                                                    X
                                                                                                                                    (Continued)

-------
                                                           TABLE 2-4 (continued)

                                 SUMMARY OF PHASE I FINDINGS AND PRINCIPAL ACTION TO BE STUDIED IN PHASE II
AS DETERMINED BY AEC (NOW DOE)
Utah
Green River
Mexican Hat
Salt take City
Wyoming
Converse County
Totals
Years Operated
1958-61
1957-65
1951-68
1962-65
Tons of Tailings Ra in Ci I II III
123
2,200
1,700
187
25,256
20 XX
1,560 X X
1,380 XXX
60
13,950
IV

X
X
Notes:

  I - The removal of tailings and other radioactive materials from the site to a more suitable location.

 II - Stabilize tailings or complete or improve stabilization to prevent vind and water erosion.

Ill - Decontamination of millsite or immediate  area around  tailings pile.

 IV - Complete or improve fencing and posting of millsites  and tailings areas.

  V - Determine levels of radioactivity in structures where tailings may have been used in construction and
      determine costs and measures needed for remedial action vhere warranted.

 VI - Conduct ground water surveys in immediate area  of millsite and tailings.

VII - No phase II study proposed at this time.
                                                                                                                      VI      VII

-------
and other architectural features,  such as fences, have changed; all




buildings have been removed at the Shiprock site, for example.  And wind




and water have eroded tailings at all of the sites.









2.3.2    The Phase II studies




    The Phase II studies (FB 76-78) of 23 sites  (Table 2-2) began in  1975.




The studies  fixed site  ownership  and  determined  hydrologic, meteorologic,




topographic, demographic, and  socioeconomic characteristics of the inactive




mill  sites and  alternative  sites  to which  tailings might  be moved.  Radio-




logical  surveys  of air,  land,  and water  near  the tailings  sites  included




estimates  of exposures to  individuals and  nearby populations  and identifi~




cation of  offsite use  of tailings.  Finally,  the studies  developed




 alternative  remedial action plans for each site  and  analyzed  each plan's




 cost.









     The scope of the Phase II studies at each site was guided by the  recom-




 mendations of the Phase I  studies (Table 2-4).  This Environmental Impact




 Statement incorporates many of the results of these  studies,  but the




 Phase II reports themselves offer more  detailed, site-specific information.
                                      2-18

-------
                          References for Chapter 2

(AE 74)  U.S.  Atomic Energy Commission,  1974,  "Phase I Studies  of Inactive
         Uranium Mill Sites and Tailings Piles" (Summary and individual
         site  reports).

(AU 70)  Augustine,  R.J.,  August 1970, "Inventory of Active  Uranium Mills
         and Tailings Piles at Former Uranium Mills," ISDHEW.

(FA 76)  Facer,  J.F., Jr.,  "Production Statistics" (of the Uranium
         Industry),  presented at Grand Junction Office Uranium  Industry
         Seminar,  Department of Energy,  October 1976.

(FB 76-78)  Ford,  Bacon,  and Davis,  Utah,  Inc., "Phase II—Title  1,
            Engineering Assessment of Inactive Uranium Mill  Tailings,"  20
            contract reports for Department of Energy Contract  No.
            E(05-l)-1658,  1976-78.

(JO 77)  Jones,  J.Q-, October 1977,  "Uranium Processing Developments,"
         Grand Junction Office, Department of Energy.

(ME 71)  Merritt,  R.C., 1971, "The Extraction Metalurgy of Uranium,"
         Colorado  School  of Mines Research Institute, Golden, Colorado.

(NR 79)  U.S.  Nuclear Regulatory Commission,  "Generic Environmental Impact
         Statement on Uranium Milling,"  April 1979, NUREG-0.511.

(TH 79)  Personal  conversation with  John Themelis, October 1979,  Grand
         Junction Office,  Department of  Energy.
                                    2-19

-------
                               3:   SOURCE TERMS








3.1  Introduction



     In assessing the potential health and environmental impact of the




tailings, the "source terms" 	 that is,  the amounts and concentrations of




radioactivity and toxic chemicals in the tailings piles and in off-site




contamination — are particularly important.  This section discusses these




sources.








3.2  Radioactivity Source Terms



     From 1948 through 1978, nearly 157 million tons of ore were processed




at all uranium mills (DO 79), yielding some 328,000 tons of UjOg, a




uranium-rich compound called "yellowcake."  Chemicals added in processing




become part of the tailings, so the tailings solids and the ore weigh about




the same.  The 22 inactive sites designated under PL 95-604 contribute




about one-sixth of all tailings, or about 26 millions tons, deposited in




piles covering about 1,000 acres (Table 3-1).  The remaining tailings are




at active sites licensed by  the NRC or Agreement States, and will be




subject to forthcoming EPA standards.








     Most of the mills at the  now-inactive  sites used acid solvents to




dissolve uranium out of the  ore.  All mills discharged a mixture of solid



tailings and liquids to an impoundment area, unusually referred  to as a




tailings pond or tailings pile.  Part of the liquid was recycled to the




mill but most of it evaporated or  seeped into the ground.  Seepage of

-------
                      TABLE 3-1



RADIOACTIVITY IH TRACTIVE URAHIUM MILL TAILORS PILES

1.
2.
3.
4.
5.
6.
(0
I
ro
7.
8.
9.
10.
11.
12.
13.
14.
15.
SITE
Arizona
Tuba City,
Arizona
Darango,
Colorado
Grand Janction,
Colorado
Gtmnicon,
Colorado
Maybell,
Colorado
Baenrita,
Colorado
Hew Si fie,
Colorado
Old Rifle,
Colorado
Slick Rock {HC),
Colorado
Slick Rock (DC),
Colorado
Lovaun,
Idaho
Aabrosia Lake,
Dew Mexico
Shiproek,
New Mexico
Lakeviev,
Oregon
TtMS OF
TAUIMGS
(MIU.IORS)
1.2
0.8
1.6
1.9
0.5
2.6
0.7
2.7
0.4
0.04
0.35
0.09
2.6
1.5
0.13
AREA OP
TAILINGS
(ACRES)
30
22
21
59
39
80
23
32
13
19
6
5
105
72
30
AVERAGE
ORE GRADE*1*
0.04
0.33
0.25
0.28
0.15
0.098
0.30
0.31
0.36
0.28
0.245
0.19
0.23
0.25
0.15
AVERAGE
RADIUM-226(2)
(pCi/8)
50
924
700
' 784
420
274
800
868
1,008
784
686
532
644
700
420
AHHOAL RADOH
RELEASE
(Ci/yr)
200
2,600
1,900
5,900
2,100
2,800
2,300
3,600
1,700
1,900
500
300
8,600
6,400
1,600
TOTAL
SADIBM-226***
(Ci)
50
670
1,200
1,350
200
640
490
2,130
320
30
70
10
1,520
950
50
MAX. MEASURED
RADIOM-226<5)
(pCi/g>
1,300
1,880
1,800
1,800
1,100
600
1,2OO
1,900
5,400
350
120
244
900
4,000
420
RADOR-222: MEASURED
RELEASE RATE
(pCi/m2-«ec)
14-29
11-406
35-312
25-656
476
75-99
763-2,540
70-1,400
210-1,300
4-246
6-24
50-150
40-300
53-157 f7l
(440-1200-2200)'' "
187-710ra)

-------
                                                                          TABLE 3-1 — Continued

                                                     RADIOACTIVITY IN INACTIVE URANIUM MILL TAILINGS PILES

                                                                                                    TOTAL
          SITE
                     TONS OF     AREA OF      AVERAGE       AVERAGE       ANNUAL RADON

                     TAILINGS    TAILINGS    ORE GRADE(1)  RADIUM-226(2)   RELEASE(3)
                                                                                                               MAX. MEASURED
                                                                                                 RADIUM-226W  RADIUM-226<5)
                            (MILLIONS)    (ACRES)
                                                            (pCi/g)
(Ci/yr)
               (Ci)
                                             (pCi/g)
                                                                           RADON-222:   MEASURED

                                                                              RELEASE RATE

                                                                              (pCi/m -sec)
to
 I
co
16. Canonsburg,
        Pennsylvania    0.4

17. Falls City,
        Texas           2.5

18. Ray Point,
        Texas           0.49

19. Green River,
        Utah            0.12

20. Mexican Hat,
        Utah            2.2

21. Salt Lake City,
        Utah            1.7

22. Converse County,
        Wyoming        0.19

23. Riverton,
        Wyoming        0.9
 18


146


 47


  9


 68


100


  5


 72
0.16


0.185


0.29


0.28


0.32


0.12


0.20
448


518


812


784


896


336


560
 8,400


 3,100


   900


 6,800


11,500


   200


 5,100
              1,020


                230


                 20


              1,560


              1,380


                 60


                544
                                                                                                            4,200


                                                                                                              160


                                                                                                              264


                                                                                                              220


                                                                                                             1,900


                                                                                                             2,000


                                                                                                              650


                                                                                                             1,100
    185-296


     3-78


     427


    32-128


    16-1,600


     1-20(9)
(130-300-650)

   190-2,860


    51-81
                                                                                                                                                   (10)
(6)
(7)

W
(')
(10>

(11)
            Phase  II Reports  (TB 76-78).
            Calculated  from average ore grade, assuming 700 pCi/g per 0.25%.
            Calculated  from average radium-226, assuming 1 pCi/m^-sec of radon-222 is released  (annual average) for each pCi of radium-226
                per gram of tailings.
            Phase  I summary Report (AE 74).
            Phase  II Reports  (FB 76-78).  Value shown is for highest reported soil, sediment, or tailings sample.  Tailings were not sampled
                in all  cases.
            phase  II Reports  (FB 76-78), unless indicated otherwise.
            Bernhardt,  et  al.  (BE 75), reported values ranging from 590 to 1,320 pCi/m2-sec for uncovered and 440 to 2,200 pCi/mz-sec for
                stabilized tailings.
            Bernhardt,  et  al.  (BE 75), reported values for stabilized tailings ranging from 3 to 31 pCi/m2-sec.
            Measurements by FBDD are based on a sample of tailings in a barrel, with varying moisture contents.
            Bernhardt,  et  al.  (BE 75), reported values for 11 sites ranging from 130 to 650 pCi/mZ-sec , with a median of about 300 pCi/m^-see.
                Measurements  by Bernhardt indicated overlapping ranges of radon release rates for uncovered and covered (up to several feet) tailings.
            EPA-520/1/76-001.

-------
contaminants occured at many sites, the extent depending on the location
and design of the impoundment area.  Some of the now-inactive mills
discharged liquid directly into surface streams.


    Uranium is the first member of a radioactive "decay series"; in other
words, uranium decays to thorium, which in turn decays to radium, with the
chain ultimately terminating with lead (see Fig. 4-1).  Because of a
condition called "secular equilibrium," the radioactivity of each member
of the decay series is the same as that of the parent, uranium-238.

%
     The  amount  of  radioactive  thorium  in  the  tailings  pond  liquid  at
acid-process mills is much higher  than at alkaline-process  mills,  because
it dissolves  readily  in  acid  solvents  but not  in  alkaline  solvents.   About
5% or less  of  the  radium in  the  ore  is dissolved  by either  method.
Essentially all of the  dissolved thorium, radium  and radionuclides  other
than uranium are discharged  to the tailings  pond  (SE 75).


     The  solid  portion of the  tailings  can be divided into  coarse sands and
finer slimes.   In  the acid process,  residual uranium and radium content in
the slimes  is  about  twice that in  the  sands,  while  thorium  content  appears
to be about the same  in  both  sands and slimes.


     Since uranium  is  removed  in  milling,  the uranium radioactivity  levels
in the tailings are  substantially  less than  the radium radioactivity
levels.  Thorium-230  levels  in tailings are  probably close  to those of
                                      3-4

-------
radium-226, though the dominance of either may change within the pile

because of variations in the mill process and any efforts to precipitate

radium in the tailings pond.



    The activity of such radium decay products as radon in tailings is

somewhat lower than that of the parent radium, since radon is a gas which

can escape from the pile.  Only about 20% or less of the radon produced

from the radium, however, leaves the tailings particles, so 80% or more of

the decay products of radon are formed within the particles (CU 73).  The

depth of tailings and cover as well as porosity and moisture content

largely determine how much of the radon leaving the tailings particles is

ultimately released to the atmosphere.



    Table 3-1 shows the  estimated quantity of tailings, area of tailings,

average ore grade, estimated average radium-226 concentration  (based  on

average ore grade), annual radon release  estimate,  total curies(l)  of

radium, maximum measured radium concentrations, and limited  information  on

measured radon-222 release rates.  For "upgrader"  sites where  slimes  have

been removed, the  average  concentration  is  probably lower  than that

estimated  from  the average  ore  grade.  Green River, Monument Valley,  Slick

Rock  (UC),  and  Converse  County  were  upgrader sites.   The Naturita mill

operated as  an  upgrader  only for a short  period before  it  was  shut  down.
        curie (Ci)  is  the basic unit of radioactivity,  equal  to 37  billion
 nuclear disintegrations per second.
                                      3r5

-------
As shown in Table 3-1, the maximum radium concentration found in samples




ranged from about 1/5 to 25 times the average value estimated from the




average ore grade.








3.3  Nonradioactive Contaminants




    A number of nonradioactive toxic substances from ore or from chemicals




used in processing have been found in the liquid and solid portions of




uranium mill effluents (SE 75).  Information on their concentrations in




tailings and ground water at the inactive sites is part of the Phase II




reports (FB 76-78).  The contaminants present in a mill waste stream




depend on the source and type of processing; Table 3-2 gives examples of




the elements and compounds found in a tailings pile at one inactive




alkaline-leach uranium mill.  The ratio of the concentration in slimes  to




that in a "background" soil sample is included.  Uranium and thorium are




radioactive, but are also included in this table.  Table 3-3 indicates




additional elements and compounds which have been reported in other



tailings piles.









    Ground water has been contaminated at some inactive uranium mill




sites.  The primary source of such contamination within the first  few




decades after mill operation is the tailings pond water discharged while




the pile is active.  Kaufmann, e£ al. (KA 75), estimated that 30%  of the




water  from two active tailings pond seeped into the ground.  Purtyman,  et_




al., estimated seepage loss from an inactive  pile in New Mexico during its




active life as 44% (PU 77).  The NRC DGEIS on Uranium Milling uses a model




which  assumes a 38% water loss by seepage (NU 79), and estimates movement




of seepage through unsaturated soil, formation of the seepage bulb in the

-------
                                TABLE 3-2
     Elements and Compounds Measured  in an  Inactive Tailings
Concentration in
Element Tailings Sands
or Compound (parts per million)
Uranium 211
Molybdenum — (b)
Selenium 31.3
Vanadium
Arsenic
Chlorine
Antimony
Calcium
Cerium
Bromine
Sodium
Iron
Terbium
Cobalt
Aluminum
Barium
Europium
Gallium
Lanthanum
Manganese
Scandium
Zinc
Chromium
Potassium
Thorium
Titanium
Ytterbium
Cesium
Hafnium
Magnesium
Rubidium
Tantalum
Neodymium
Strontium
Tungsten
204
27
ND^C'
0.69
2830
90
2.5
1080
1060
0.37
2.9
4280
663
0.95
5.5
24
335
2.5
15
10
2350
4.6
1330
1.6
2.4
3.6
4190
82
0.42
41
183
0.49
Concentration in
Tailings Slimes
(parts per million)
380
300
133
2050
79
580
2.2
2670
163
7.6
1970
3550
0.63
9.3
6660
572
1.48

44
388
7/\
.0
68
25
2110
8.8
2140
2.9
2.4
4.8
2180
63
0.62
95
ND
ND
Ratio of
Concentration in
Slimes to Background
160
160
100
70
1 O
18
V 1
13
5




2F
.5





2

2
1
1
1
1
*"*""
1
1
i
i




<«>  (DR 78)
(b)  — indicates no data
     ND indicates not detected
                                     3-7

-------
                                TABLE 3-3



Additional Elements and Compounds Found in Uranium Mill Tailings(a)





                  Boron                        Nickel




                  Cadmium                      Silver



                  Copper                       Zirconium



                  Gold                         Cyanide



                  Lead                         Silicate



                  Mercury
(a) (FB 76-78)
                                     3-8

-------
saturated soil zone, and movement of pollutants with the ground water.




For its model mill, in an arid region, the NRC concluded that about 95% of




the possible contamination was associated with the active phase of the




pile and only 5% with the long-term losses from the inactive pile




(NR 79).  However, studies by Klute and Heermann (KL 78) indicate that




even in dry climates precipitation can produce a downward flow of water




through the tailings.








     Tailings piles at inactive mill sites already have lost much of the




water present when they were formed.  The water has evaporated, gone




underground, or run off on the surface.  Any future contamination of water




by the pile mainly would result  from erosion, rain, flooding, or the




flushing action of seasonal changes in the water table where it intersects




a pile.  The quality of streams  and lakes could be degraded by seepage




from a pile, or by  tailings which run off or are blown into them.




Table 3-4 indicates inactive and active  sites where elevated concentra-




tions of nonradioactive contaminants have been found in ground water near




tailings piles.








3.4  Off-Site Contamination



     In  1972, EPA and AEC, using a mobile detector in the vicinity of




tailings sites,  located areas with higher than normal gamma radiation.  To




determine the source, teams  from EPA  and the State health departments




conducted further gamma surveys. At  hundreds  of  locations, uranium mill




tailings were found under  or within 10  feet of structures (FB  76-78) and,




at  additional hundreds  of  locations,  more than 10 feet  from a  structure.
                                     3r9

-------
                                 TABLE 3-M

           Elements/Compounds Reported in Elevated Concentrations
              In Ground Water in the Vioinity of Tailings Piles
        Site

Ambrosia Lake, NM(a)

Ray Point, TX(b)

Green River, UT(c)

Gunnison, C0(d)


Falls City, TX(e)
Grants Mineral Belt,  NM(f)
     (Active Mills)
Contaminants

Barium, Lead, Vanadium

Arsenic

Arsenic, Chromium, Lead, Selenium

Arsenic, Barium, Chromium, Iron,
Lead, Selenium, Vanadium

Arsenic, Barium, Chromium, Iron,
Lead, Selenium, Radium, Vanadium

Polonium, Selenium, Radium,
Vanadium, Uranium, Ammonia,
Chloride, Nitrate, Sulfate
(a)  (FB 76-78) (GJT-13)
(b)  (FB 76-78) (GJT-20)
(c)  (FB 76-78) (GJT-HO
(d)  (FB 76-78) (GJT-12)
(e)  (FB 76-78) (GJT-16)
     (KA 75)
                                     3-10

-------
(These figures exclude Grand Junction, where there is a separate remedial

action program.)  Following the 1972 surveys, tailings from Cane Valley,

Arizona, and Edgemont, S. Dakota, have been used off-site, and in at least

one case—Salt Lake City—the gamma surveys were not completed.  Table 3-5

shows the number of locations near each designated site where the use of

uranium mill tailings has been detected.




    EPA began a complementary gamma radiation survey in the spring of 1974

to determine the extent of contamination by wind- and water-eroded

tailings at the inactive uranium mill sites (DO 75).  Gamma radiation from

the ground was measured by adjusting detector readings for contributions

from other sources, including direct and scattered radiation from the

tailings pile.  Gamma radiation from the ground at levels above the normal

background indicated contamination by tailings.  Contour  lines

corresponding to gamma radiation levels above background  of 40 uR/hr,(D

lOuR/hr, and zero  (i.e., background), were plotted on maps of each site to

show the locations of contamination (FB 76-78).  Table 3-6 provides

estimates of the areas contaminated at a given gamma radiation level for

the 20 inactive sites surveyed.  The Oregon Department of Human Resources

requested that the Lakeview  site not be surveyed because  the pile was

stabilized during  the summer of 1974.  The Canonsburg, Pennsylvania, site

also was not included.
       roentgen  (R) is a unit measuring the electrical charge gamma rays
release in air.  A microroentgen  (uR) is one millionth of a roentgen.

-------
              TABLE 3-5




Gamma Radiation Anomalies  and Causes^8)
Location
Arizona
Cane Valley(b)
Cameron
Cutter
Tuba City
State Total
Colorado
Cameo
Canon City
Clifton
Collbran
Craig
Debeque
Delta
Dove Creek
Durango
Fruita
Gateway
Glade Park
Grand Junction^)
Grand Valley
Gunnison
Leadville
Lotna
Mack
Mesa
Mesa Lakes
Molina
Naturita
Nucla
Palisade
Plateau City
Rifle
Salida
Slick Rock
Uravan
Whitewater 	

Idaho
Idaho City
Lowman
Salmon
State Total ' 	
Number of
Anomalies
Detected

19
3
5
17
44

3
187
1083
145
86
109
43
83
354
1276
17
1
14542
110
47
91
199
90
123
3
43
33
13
939
28
810
64
9
209
55
0,795

3
12
77
	 52 	
Cause of Anomaly
Tailings

15


7
22

1
36
159
4
8
2

59
118
58
mfV
12

5178
10
3
•J
18
10
6
1


10
3
107
1
168
6
3
208

6191




	 -T75 	
Radioactive Source
or Ore

4
i
J. .
5

10 ~~* '


24
34



1 O
iy
67
/ A
48

(d)










39
*> T
2.1


4
7560^




_. 	 2 	
Natural
Radioactivity




3
3


99
14

46
1
29
2
67
26


-(d)

28
65
4




1
2
14

1
52

2

453^


2
3
65
Unknown



2
7
/
9


2
28
876
139
25
106
10
3
102
1144
3

2135
98
7
6
181
82
120
3
43
2
2
779
27
614
4

1
t. Q
49
6591


1

9
                                                          10
                     3-12

-------
         TABLE 3-5 (Continued)
Gamma Radiation Anomalies and Causes(a)

Location
New Mexico
Bluewater
Gamer co
Grants
Milan
Shiorock
State Total
Oregon
Lake view
New Pine Creek
state Total
South Dakota
Edgemont
Edgemont
and Dudley(e)
Hot Springs
_ Provo
state Total
Texas
Campbell ton
Coughran
Falls City
Fashing
Floresville
George West
Karnes City
Kenedy
Panna Maria
Pawnee
Pleasanton
Poth
Three Rivers
Tilden
_ Whitsett
state Total
Number of
Anomalies
Detected

2
5
101
41
9
158

18
4
22

55

84
45
4
165

7
1
5
1
16
10
10
22
3
1
21
15
5
11
1
129

Cause of
Anomaly

Radioactive Source Natural
Tailings

1

7
5
8
21





43

17

3
63



2



2
1




1


6
or Ore

1

50
27
1
79

2
1
3

3

16
3
1
23

1


1



1

i
3




7
Radioactivity


5
25
1

31

10

10

1

51
17

69

6
1
3

14
10
6
13
3

17
14
2
11
1
101




19
8

27

6
3
9

8


25

33





2

2
7


1
1
2


15
        3-13

-------
                                TABLE 3-5 (Continued)
                       Gamma Radiation Anomalies and Causes ^


Location
Utah
Bland ing
Bluff
Cisco
Crescent Junction
Green River
Magna
Mexican Hat
Mexican Hat
(Old Mill)
Moab
Monticello
Salt Lake City
Ly/j « C&UG VfllXcv \
SWltll tPl 1 TTIOO VM
— • **•*• ^ n uaxL^iiKo n<
Radioactivity

3



1
21


1
6

76

108

3
1
10
2
16

5
3
•J
53
33
94
955(d)
»s not included in

»s oeen m progress
Unknown

4
1

1
7
3



21
9
64
1
111







1
2
20
23
4T
6851
initial

since 1972
                                               °ot
                                          .
(e)  Survey of  additional  anomalies  conducted in  1978.
{fi  Salt Lake  City was  not  completely  surveyed.
                                         3-14

-------
                           TABLE 3-6




Contaminated Areas Around Inactive  Uranium Mill  Tailinea  Piles
Colorado
Rifle (New),
Colorado
Rifle (Old),
Colorado
Slick Rock(NC),
Colorado
47

30

81

15

21

20

7
— — __

12 26

322 452

—

114 169

17 44

12
314

68

745

—

312

243

33
Slick Rock (UCC),
Colorado
Lowman,
Idaho
Ambrosia Lake,
New Mexico
Shiprock,
New Mexico
19

y(f)

104

118
3 41

11

210 390

126
81

16

617

229
                           3-15

-------
                                       TABLE 3-6  (Continued)

                 Contaminated Areas Around  Inactive Uranium Mill Tailings Pi
                                               APPROXIMATE AREA (Excl. Pile) (Acres)
Site
               Tailings
               Pile
40 uR/hr above
Background	
                                                         10-40 uR/hr above
                                                            Background	
 0-10 uR/hr
above Background
15.
Oregon
                        30
16.  Canonsburg,'1*)
      Pennsylvania      19

17.  Falls City,
      Texas            142
18.  Ray Point,
      Texas             48

19.  Green River,
      Utah               9

20.  Mexican Hat,
      Utah              77

21.  Salt Lake City,
      Utah              94

22. Converse County,
      Wyoming           42

23.  River ton,
      Wyoming           72
                                      139
                                       19
                                       114
                                                          256


                                                           39


                                                           44


                                                          127


                                                          198


                                                           88


                                                           99
                                                    411


                                                     94


                                                    153


                                                    457


                                                    510


                                                    187


                                                    460
(a)  Reference DO 75
(b)  Rock outcroppings and scattered ore made measurements difficult.
(c)  Ponds covered with topsoil.  Contaminated area could not be determined.
(d)  Due to extensive development around site, contaminated area could not be determined.
(e)  Contamination from plume extends several miles down valley
(f)  Mill residue stockpile areas
(g)  Gamma survey not done, at request of State.
(h)  Gamma survey not done.
(i)  Not included under UMTRCA
(j)  — indicates data not available
(k)  Includes tailings, overburden piles, and waste dumps.  Tailings only constitute  about  2.5
     acres.
                                        3-16

-------
                            References for Chapter 3


  (AE 74)     U.S. Atomic Energy Commission, 1974, "Phase I Studies of
              Inactive Uranium Mill Sites and Tailings Piles" (summary and
              individual site reports).

  (BE 75)      Bernhardt,  D.E.,  Johns,  F.B.,  and  Kaufmann,  R.F.,  1975,  "Radon
              Exhalation  from Uranium  Mill Tailings Piles, Description and
              Verification of the Measurement Method," U.S. Environmental
              Protection Agency, Officer of Radiation Programs, Technical
             Note ORP/LV-75-7(A).

 (CU 73)     Culot,  M.V.S.,  Olson,  H.G.,  Schiager, K.J.,  1973, "Radon
             Progeny Control in Buildings,"  Colorado State University.

 (DO 75)     Douglas,  R.L. and  Hans, J.M., Jr.,  August  1975,  "Gamma
             Radiation Surveys  at Inactive Uranium Mill Sites,"  Technical
             Note  ORP/LV-75-5.

 (DO 79)     U.S.  Department  of Energy, January  1, 1979, "Statistical  Data
             of  the  Uranium  Industry," DOE Grand Junction  Office, Colorado,
             GTO-100 (79).                                                -

 (DR 78)      Dreesen,  D.R., Marple, M.L., and Kelley, N.E., 1978,
             "Contaminant Transport, Revegetation, and Trace  Element
             Studies at Inactive Uranium Mill Tailings Piles," in
             Proceedings  of the Symposium on Uranium Mill  Tailings
             Management, Colorado State University, Fort Collins, 111-139.

 (FB  76-78)   Ford, Bacon, and Davis, Utah, Inc.,  "Phase II-Title 1,
             Engineering Assessment of Inactive Uranium Mill Tailings," 20
             contract  reports for Department of Energy Contract No.
             E(05-l)-1658, 1976-1978.

 (KA  75)     Kaufmann, R.F.,  Eadie,  G.G.,  and Russell, C.R., 1975, "Summary
             of Ground Water Quality Impacts of Uranium Mining and Milling
             in the Grants Mineral Belt, New Mexico,"  U.S. Environmental
            Protection Agency, Office of Radiation Programs,  Technical
            Note ORP/LV-75-4.

(KL 78)     Klute, A., and Heermann,  D.F.,  September 1978, "Water
            Movememnt in Uranium Mill  Tailings Profiles," Environmental
            Protection Agency,  Office  of  Radiation Programs,  Technical
            Note ORP/LV-78-8.

(OR 73)     Office of Radiation Programs, March  1973,  "Summary Report of
            the  Radiation Surveys Performed  in Selected Communities," U.S.
            Environmental Protection Agency.
                                    3-17

-------
                   References for Chapter 3  (continued)
(PU 77)     Purtyman,  W.D.,  Wienke,  C.L.,  and  Dreesen,  D.R.,  "Geology and
           Hydrology  in the Vicinity of the Inactive Uranium Mill Tailings
           Pile,  Ambrosia Lake.  New Mexico."  T.A-fifl-*o_Me   T	»i	
                      TK   t6'  NW Mexico'"  LA-6839-MS,  Los  Alamos
                      Laboratory,  New Mexico, 1977.
(SE 75)     Sears,  M.B.,  et  al.,  1975,  "Correlation of  Radioactive  Waste
           ine?hrSuC?pf V"?  'helEn*ir°nmental  Impact  of Waste Effluents
           in the  Nuclear Fuel  Cycle for Use  in Establishing  'as Low as
           OakCRid:e Nat-UidrT\Millin8 °f Uranium °-s,"lwo Volume"
           Oak Ridge National Laboratory report ORNL-TM-4903.
                                   3-18

-------
                              4:  HEALTH EFFECTS

 4.1   Introduction
      As  metallic ore  waste,  uranium mill  tailings are unique because of the
 amount of  radioactivity they contain.   It  is  radioactivity that constitutes
 their principal  health hazard,  though  nonradioactive toxic chemicals such
 as arsenic,  lead, selenium,  mercury, sulphates,  and  nitrates may also be
 present.   Milling uranium-bearing ore  removes about  90*  of the  uranium.
 The remainder, along  with  other radioactive material and toxic  chemicals in
 the processed  ore,  is discarded in  the liquid waste  and  solid tailings.

      Most  of the uranium in  uranium ore is uranium-238,  a radioactive
 isotope  that decays over billions of years to become lead-206,  a stable,
 nonradioaotive element.  The lengthy decay process passes through a  series
 of intermediate  elements called decay  products,  such as  thorium-230  and
 radon-222; these,  too,  are radioactive.  Fig.  4-1  traces the steps in the
 decay series.  Uranium  decays since  the ore was  formed millions of years
 ago have built up an  inventory  of the  decay products identified in Fig.
 4-1.   In various concentrations,  all are present  in  uranium  mill  tailings.

      Uranium mill tailings emit three  kinds of radiation:  alpha  rays, beta
 rays, and gamma  rays.  All are  forms of ionizing radiation,  which breaks up
molecules into electrically  charged fragments, or ions.   In  tissue,
 ionization can produce harmful cellular changes.  At  the  low radiation
 levels naturally encountered in the environment we expect the effects of
such  changes to  be detectable only with difficulty.  Studies show, however,

-------
FIGURE 4-1. URANIUM-238 DECAY SERIES
Uranium-238
4.5 billion
years
I
alpha
I
Thorium-234
24 days


Protactinium
234
1.2 minutes
s
f beta,
gamma

Uranium- 234
250,000
years
1?
beta,
^ gamma
I
alpha,
gamma
Thorium-230
80,000
years
t
alpha,
gamma
Radium-226
1,600 years
I
! alpha,
gamma
Radon-222
3.8 days
(alpha.
gamma
Polonium-
218
3 minutes
alp
ha
Lead-214
27 minutes

(ELEMENT)
(HALF-LIFE)
I
(PARTICLE OR
RAY EMITTED)
\
Ionium- Polonium-
214 210
1/6300 sec 138 days
| 	 	 , jf. *
'gamma J*'3
Bismuth-214 D. .
19.7 minutes alpha, B.smuth-210
gamma 5davs alpha,
	 -j ,.J v
	 . X 1
beta, >"_ f
/gamma LearOm /beta,
r Lead-210 X gamma Lead- 206
22'3 V«rs ' $table
                     4-2

-------
 that people exposed to high doses of radiation have a greater chance of

 developing cancer.  If the ovaries or testes are exposed, moreover, the

 health or development of future children may be damaged.




      No one can predict with precision the increased chance of cancer after

 exposure to radiation.  EPA and other Federal agencies base risk estimates

 on studies of persons exposed  at high doses,  and assume that at lower doses

 the effects will be proportionately less.   Sometimes this assumption may

 overestimate or underestimate  the actual risk,  but it is the best that can

 be done at present (EP 76).




      Alpha,  beta,  and  gamma radiation all  can cause harm.   But the major


 threat  to health comes from breathing air  containing radon decay products

 with short  half-lives(1)—polonium-218,  for example—and exposing the

 lungs and other internal  organs  to the alpha  radiation these decay products

 emit.   In addition,  radioactive  material in the  tailings pile may expose

 people  directly to  gamma  rays, or tailings  particles may be  breathed  or

 ingested.  Except within  a  few miles  of  the pile,  however, the potential

 harm from breathing  radon decay  products is much greater.




     The  body's  internal  organs  would  still be exposed  to  alpha  radiation


even if uranium  tailings  piles suddenly  disappeared.   Radium, uranium,

thorium,  and other radioactive elements  naturally present  in  ordinary rock

and soil emit alpha  radiation; 1  picocurie  of radium per gram of  soil is  a
(1)A half-life is the time it takes for a given quantity of a radioactive
isotope to decay to half of that quantity.

-------
typical concentration.   Outdoor air contains a few tenths of a pCi of radon
per liter (UN 77).  Normal eating and breathing introduces these and other
radioactive materials into the body, increasing the potential for cancer
and genetic changes.  This discussion, therefore, compares the health risks
from tailings to those from normal exposure—not to justify the tailings
risk, but to provide a realistic context.

4.2  Radon and Its  Immediate Decay Products
     The most important decay product in the  uranium-238 decay series,  for
the  purpose of defining the longevity of tailings' radioactivity,  is
thorium-230, which  decays  to become  radium-226.   Because the  half-life  of
thorium-230  is 80,000 years, uranium tailings represent an  essentially
permanent  source  of radium contamination.   Radium in  its usual  chemical
form is relatively  insoluble  in water,  so  it can be controlled  much as
 other  solid toxic materials with similar chemical characteristics.   But
 radon-222,  the  radium-226 decay product, is a nonreactive  radioactive gas
 that diffuses from  the  pile and becomes airborne.  The half-life of radon
 is 3.8 days, so some radon atoms can travel thousands of miles before they
 decay.

      As shown in Figure 4-1,  the radon decay series leads through seven
 principal members before ending with nonradioactive lead-206.  The
 potential health effects of breathing the short half-life radioactive  decay
 products immediately following radon are most important.  Members of the
 decay  chain with relatively long half-lives  (beginning with  lead-210,  with
 a 22-year half-life) are more  likely to be ingested than breathed  and
 represent  less of  a risk.

-------
      The principal short half-life products of radon-222 are polonium-218,



 lead-214, bismuth-214, and polonium-214—decaying, for the most part, in



 less than an hour.  Polonium-218, the first decay product, has a half-life



 of just over three minutes.  This is long enough for most of the



 electrically charged polonium atoms to attach themselves to microscopic



 dust particles,  less than a millionth of a meter across, in the air.   When



 breathed, such small particles have a good chance of sticking to the  moist



 epithelium lining of the bronchial tubes in the lung.   Most of the inhaled



 material is eventually cleared from the bronchi by mucus,  but not quickly



 enough  to keep the bronchial epithelium from being exposed to alpha rays



 from polonium-218 and polonium-214.  These highly ionizing rays pass



 through  several  types of lung cells,  but the doses they deliver to cells




 that  eventually  become cancerous  cannot adequately be  determined.   To do so



 would require  more detailed knowledge than we have of  the  deposition



 pattern  of  the radioactive  particles  in the lung  and the distances from



 them  to  the  cells.   Further,  there  is even some disagreement  about which of



 the several  types  of bronchial  cells  the  cancers  originate  in.   Therefore,



 we base  estimates  of lung cancer  risk from inhaled  radon decay  products  on



 People's exposure  to  radon  decay  products  rather  than on the  dose absorbed



 in lung  tissues.








     Exposure  to radon decay products  is measured by a specialized unit



called the working level (WL).  A WL  is any combination of short half-life



Padon decay products which emits  130,000 million electron volts of



alpha-ray energy in one liter of air.
                                     4-5

-------
     The WL was developed to measure radiation exposure to workers in
uranium mines.  The common unit of cumulative exposure is the working level
month (WLM), or occupational exposure to air containing one WL of radon
decay products for a working month, defined as 170 hours.  Continuous
exposure of a member of the general population to one WL for one year can
be shown to be about 27 WLM (EP 78).

l|'3 E3timates of the Lung Cancer Risk from Inhaling Radon Decay Products
     The very high incidence of lung cancer mortality among underground
miners is well documented (EP 78, AR 79).  Uranium miners are particularly
affected, but lead, iron, and zinc miners exposed to relatively low levels
of radon decay products also show an increased lung cancer mortality that
correlates with exposure.  The type of lung cancer most frequently observed
moreover, is rather uncommon in the general population.

     Risk estimates for the general public based on these studies of miners
are far from precise.   First and most important, the small number of miners
injects considerable statistical uncertainty (see Figure 4-2) into tne
number of "excess" lung cancer cases (that is, the number of cases beyond
those that would occur in any event).  Second, the miners were exposed to
much higher levels of radon decay products than occur in the general
environment.  Third, the exposure levels are uncertain.  Fourth,
significant demographic differences between the miners and the public-the
miners were healthy males over 1. years old, many of whom smoked-imperil
an extension of the results of the studies to the general public.
                                     4-6

-------
                               FIGURE 4-2
   80
   70
§
o
 - 60
cc
iu
o
<
o
o
2

Ul
CD
o
o
I
   50
   30
  20
  10
                            All
               JO
                                            '3
                                            O CZECH-URANIUM
                                            O SWEDEN-LEAD, ZINC (A). IRON (R.J)
                                            A UNITED STATES--URANIUM
                                            • CANADA-URANIUM
                                            I 95% CONFIDENCE LIMITS
                     RD


                                                        I
100       200        300       400       500

          CUMULATIVE WORKING LEVEL MONTHS
                                                                 600
                                                                            700
                  Excess lung cancer in various miner groups as a function of their
              cumulative exposure. Note the degree of statistical uncertainty in the
              number of lung cancer attributable to radon daughters. After Archer
              (AR 79).
                                     4-7

-------
     Information from the studies of miners can yield estimates, if not


predictions,  of the risks from radon decay products to the general


population.CD  Since the miners being studied have not all died,


however, their eventual excess lung cancers must be projected from current


data by using mathematical models.




     There are two ways to use the observed frequency of  lung cancer deaths


among the exposed miners in order to estimate the  lifetime risk from


inhaling radon decay products:  (1) relative risk,  based on the  percentage


increase in  excess lung  cancer  deaths  for each  WLM,  and (2)  absolute risk,


based  on  the number  of excess lung cancer deaths per WLM  and the time, in


person-years, that the exposed population has been at risk at the time of


 the study.




      For relative risk, we conclude that a 3% increase in the number  of


 lung cancer  deaths per WLM is consistent with data from the studies of the


 underground  miners.   However, because there are important demographic


 differences  between  adult male miners and the general population  (EP  78),


 the risk to  the general population may be as low  as  1% or as high as  $%•

 For absolute risk,  we use the estimate of  10 lung cancer deaths per WLM for


 one million person-years at  risk reported  by the  National Academy of


 Sciences  (HA 76).   Both of these "risk  coefficients" are used  in this


  statement  to examine the potential consequences of lifetime exposure to


  radon decay products.  Unless we state  otherwise, we are estimating  "excess"
   (DSee "Indoor Radiation Exposure due to Radium-226 in Florida Phosphate
   Lands" (EP 78) for such an analysis.
                                       4-8

-------
cancer fatalities, i.e., those caused by elevated radiation levels and in
addition to those from other causes.

     To estimate the number of lung cancer deaths from increased levels of
radon in the environment, we have used a "life table" analysis of the
additional risk due to radiation exposure (CO 78).  This analysis takes
account of the length of time a person is exposed and the number of years a
person lives, based on the 1970 U.S. population death rate statistics, to
calculate the number of premature lung cancer deaths that would occur after
lifetime radiation exposure of 100,000 persons.  As a basis for reference,
a life table analysis for the same population indicates a 2.9% chance of
lung cancer death from causes other than excess radiation.  Using the
relative risk model, we estimate that a person exposed to 0.01 WL over a
lifetime incurs a 1.2* (1 in 80) additional chance of contracting a fatal
lung cancer.  This estimate was made assuming children are no more
sensitive than adults.  If childhood exposure results in three times
greater risk than that to adults, the estimated relative risk would
increase by about 50% (EP 78).  Using a similar life table analysis and an
absolute risk model, we estimte that a person exposed to 0.01 WL over a
lifetime incurs a 0.6% (1 in 160) additional chance of contracting a fatal
lung cancer.  Again, equal child and adult sensitivities are assumed (EP
78).

     A person's average annual risk from a lifetime of exposure may be
obtained by dividing the lifetime risk estimates given above by an average
lifespan of 71 years.   Regardless of the risk model used or assumptions

                                     H-9

-------
concerning child sensitivity, our firmest estimate is that increased levels



of radon will produce an additional 1 to 3 lung cancer deaths per year of



exposure for each 100 person-working-levels of lifetime exposure.



Person-working-levels is the population's collective exposure; that is, the



number of people times the average concentration of radon decay  products



(in working levels) to which they are exposed.








     For the U.S. population as a whole, the number of cancers is larger




using a relative than an absolute risk estimate, but not  for  all regions.




The  relative risk estimate  for each  inactive site  is based  on the lung



 cancer  death rate in that area.  Lung cancer death rates  are  lower  than the



national average in several  of the States  where  inactive  tailings sites are



 located, so  at  some of  the  localities considered in Section 4.4  the



 absolute  risk  is greater  than the  relative risk.








      Radiation risk can be  stated  in terms of  years  of  life lost due to



 cancer deaths as well  as in estimated numbers  of cancer deaths.   In the



 relative risk model, the age at  which lung cancer occurs is the same as in



 the general population.  Since  lung cancer occurs most frequently in people



 over 70 years of age,  the years  of life lost per fatal lung cancer—



 14.5 years on average—is less than for many other fatal cancers.  The




 absolute risk model assumes that lung cancer fatalities occur throughout



 life, so that each fatality reduces the lifespan  by an average  of  24.6



 years.  Therefore, even though the estimated number of lung  cancer



 fatalities using the relative risk model  is nearly twice that using  the
                                      4-10

-------
 absolute risk model, the total years of life lost in exposed populations is
 nearly the same.

      Because we used recent population data,  our assessments illustrate the
 current effects of tailings piles but do not  predict future effects.   If
 the  population sizes and locations,  lifestyle,  medical knowledge,  and other
 patterns of living affecting mortality remain unchanged,  then these rates
 of lung cancer death could persist for the indefinite future.  We  will not
 attempt to assess  future effects  of  tailings, which may either increase or
 decrease.   It is sufficiently prudent,  we believe,  to develop standards
 which  assume that  estimated risk  based on current data could persist  over
 the  indefinite future.

     For convenience, we will express results as deaths per 100 years.
 This is simply the estimated annual  rate based  on current data multiplied
 by 100.

 4.4  Effects  on Local and  Regional Population from Radon  Decay Products
     The concentration of  radon decay products  changes  rapidly with distance
 from a  pile,  requiring complex models for determining the exposure  to the
 local population.  An accurate estimate  of the  collective exposure  from a
 particular  pile would include, besides  the number  of  people  exposed,  the
 site of each  residence and work place and  its ventilation characteristics;
 the length of time a person  is at  each; and the wind  speed and  direction.
All of these  factors determine the level of radon decay products inhaled by
an individual.  Because  these data are unavailable for the inactive sites,

                                     4-11

-------
we relied upon more approximate methods to estimate regional exposure at


six of the 22 inactive sites (SW 80).  We selected these six because enough



data to allow a quantitative analysis was available.  Though limited, the



sample does include all but two of the urban sites.  Our purpose in



performing the analysis was to illustrate the potential effects of tailings



in a variety of realistic regional circumstances.






     We used U.S.  census tract data  to establish the number and locations



of exposed persons, based only on residence.   (Census tract information  is



rather precise, in urban areas, but  less  so  in  rural areas where the  tracts


are  large.)  We assumed  further that the  wind  pattern was  symmetrical



around the  pile,  with a  constant  speed of 6.5  mph.  The wind  speed



determines  the amount of dilution and, to a  lesser  extent,, the degree  of



equilibrium between  the  emitted radon and its  decay products(1).  The



 degree of equilibrium is important  because the WL for a given concentration



 of radon gradually increases as decay products accumulate.   In this



 analysis we assumed a radon-radon decay  product equilibrium of 70%  inside



 all structures and in outside air more than 25 miles  (Ho  kilometers) from



 the pile.  We assumed 50*  equilibrium in outside air within 25 miles.  We


 defined the local population as all persons living within about six miles



 (10 kilometers) of the inactive pile, and the regional population as
                  *necaui?^^^^^                               «


                                                                    -r
 »ost atmospheres are In an inte™dla?e rliatic^Mp  '**
                                      U-12

-------
persons living more than six but less than 50 miles  (80 kilometers) from



the pile.  We ignored population changes since  1970.  A future increase in




population density at several of the urban sites seems likely, but because




the actual place of residence would be critical in determining exposure and



resulting health impact, we didn't try to incorporate projected population




growth.








     Table 4-1 summarizes the results of our study of six piles at inactive




sites in terms of excess lung cancer deaths, average years of life lost per




cancer fatality, and the average number of days of life lost per exposed



person.  The estimated number of lung cancer deaths associated with a



tailings pile is highly variable, depending not only on the size of the




pile but also the population density in its immediate vicinity.  In contrast



to the estimates of national impact, described in Section 4.5, the estimated




number of fatal cancers for Utah residents based on the absolute risk model




is greater than that based on the relative risk model.  This is because the



annual lung cancer death rates in Utah are comparatively low.  The risks




listed in Table 4-1 are based on just radon emissions from the tailings




Pile, and include no additional risk from any use of tailings material in




construction.








     At Canonsburg, Pennsylvania, most of the radon exposure is received by



persons working at the site.  We estimate the risk to these workers and to



the local populations at Canonsburg as 29 or 17 fatal lung cancers per 100




years, using relative and absolute risk estimates respectively.  From the




limited data currently available on the Canonsburg site, the risks there






                                     4-13

-------
                                 TABLE 4-1

            Estimated Effect on Local and Regional Populations
         From Exposure to Radon Decay Products from Tailings Piles
Salt Lake City. Utah
          (Local Population — 361,000 persons)
  Number of fatal cancers/100 yr
  Years of life lost per fatality
  Average days of life lost
     per exposed person
              Relative Risk
                Estimates

                   72
                   15

                    0.8
Absolute Risk
  Estimates

     79
     25

      1.4
                                   (Regional Population — 494,000 persons)
   Number  of  fatal  cancers/100 yr
   Years of life  lost  per  fatality
   Average days of  life  lost
      per  exposed person
              Relative Risk
                Estimates

                     4
                    15

                     0.03
Absolute Risk
	Estimates

       5
      25

       0.06
 Mexican Hat, Utah
(No Permanent Local Population — (1970 Census))

         (Regional Population — 14,100 persons)
   Number of fatal cancers/100 yr
   Years of life lost per fatality
   Average days of life lost
      per exposed person
               Relative Risk
                 Estimates

                     0.05
                    15

                     0.01
 Absolute Risk
   Estimates

       0.05
      25

       0.02
                                      4-14

-------
                                TABLE 4-1 (cont.)

             Estimated Effeot on Local  and Regional Populations
         From Exposure to Radon Decay Products from Tailings Piles
Grand Junotion, Colorado
(Local Population — 39,800 persons)
  Number of fatal cancers/100 yr
  Years of life lost per fatality
  Average days of life lost
     per exposed person
   Relative Risk
     Estimates

        29
        15

         2.6
                       Absolute Risk
                         Estimates

                            18
                            25
                             2.9

(Regional Population — 30,600 persons)
  Number of fatal cancers/100 yr
  Years of life lost per fatality
  Average days of life lost
     per exposed person
   Relative Risk
     Estimates

         0.2
        15

         0.03
                       Absolute Risk
                         Estimates

                             0.2
                            25

                             0.03
Gunnison. Colorado
 (Local Population — 5,060 persons)
  Number of fatal cancers/100 yr
  Years of life lost per fatality
  Average days of life lost
     per exposed person
   Relative Risk
     Estimates

         3
        15

         2.3
                       Absolute Risk
                         Estimates

                             2
                            25
                             2.5

(Regional Population — 17,060 persons)
  Number of fatal cancers/100 yr
  Years of life lost per fatality
  Average days of life lost
     per exposed person
   Relative  Risk
     Estimates

         0.02
        15

         0.003
                       Absolute Risk
                         Estimates

                             0.01
                            25

                             0.004
                                    4-15

-------
                                TABLE 1-1  (oont.)

             Estimated Effect on Looal and Regional Populations
         From Exposure to Radon Deoay Products  from Tailings Piles
Rifle, Colorado (newer pile)
  Number of fatal cancers/100 yr
  Years of life lost per fatality
  Average days of life lost
     per exposed person
  Number  of  fatal  cancers/100 yr
  Years of life  lost  per  fatality
  Average days of  life  lost
      per  exposed person
(Local Population ~ 2,700 persons)
  Relative Risk
    Estimates

         1
        15

         1.5
                       Absolute Risk
                         Estimates

                             1
                            25
                             1.7

(Regional Population — 35,9QO persons)
   Relative  Risk
     Estimates

         0.03
        15

         0.003
                       Absolute Risk
                         Estimates

                             0.02
                            25

                             0.003
 Shiprook.  New Mexico
   Number of fatal cancers/100 yr
   Years of life lost per fatality
   Average days of life lost
      per exposed person
            •within 10 miles
   Number of fatal cancers/100 yr
   Years of life lost per fatality
   Average days of life lost
      per exposed person
(Local Population* -- 7,200 persons)
                                          Relative Risk
                                            Estimates
        15

         1
                       Absolute Risk
                         Estimates

                              3
                             25
                                    (Regional Population — 63,600 persons)
   Relative Risk
     Estimates

           .1
         15

         0.007
                        Absolute Risk
                          Estimates _

                               .1
                             25

                              0.01
                                      M-16

-------
seem comparable to those listed in Table 4-1 for the inactive piles located


in urban areas.





     Table 4-1 shows the estimated collective risk to people in the


region.  Within this group, the exposure and resultant risk to individuals


depends on their distance from the pile.  Table 4-2 lists the calculated


exposure and estimated individual risks from lifetime exposure, as a func-
                                                                          /

tion of distance from a hypothetical inactive pile with a radon emission


rate of 10,000 curies per year.  The assumed wind speed and exposure condi-


tions are described above.  Since the site is hypothetical rather than


actual, Table 4-2 lists only absolute-risk estimates.  At actual sites, the


estimated absolute risks as a function of distance will be proportional to


the annual radon emission (listed in Table 3-D.  For example, at a site


with emissions of 5,000 curies per year, the estimated risk to an individual


who lives a given distance away will be half of that listed in Table 4-2.





     Table 4-2 highlights the significance of distance.  At one to three


miles from the hypothetical pile, the increased radon concentration in


outside air roughly equals the normal concentration in residential


structures.  Because distance is so important, it is useful to consider


specific sites.




     In several urban areas, a few individuals live and work very near the


edge of tailings piles, where the concentration of radon is high.


Table 4-3 lists estimated working levels in outside air at homes close to


five of the urban sites.  Except for the inactive pile in Salt Lake City,



                                     4-17

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                                TABLE 4-2



                  Individual Risk From Lifetime Exposure
to Radon Decay Products from Tailings Piles
Radon
Distance from Pile Edge
(miles)
0.2
0.4
1.0
2.0
4.0
10.0
20.0
40.0
Release Rate — 10,000
Exposure
(WL)
0.013
0.005
0.001
0.0004
0.0001
0.00002
0.000004
0 . 000002
Ci per year
Chance
Lung
9200 in
3500 "
710 «
280 "
100 w
16 "
3 "
1 »

of Fatal
Cancer (a)
1 million
n n
it n
n n
ti n
it n
it n
n n
(a)Absolute  risk model.
                                    4-18

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                                  TABLE 1-3

              Estimated Risk to Nearest Residents from Inhaling

                   Radon Decay  Products  from Tailings  Piles


                    (Lifetime Exposure at Current Levels)
     Site                                Relative Risk    Absolute Risk
                                           Estimates        Estimates

Salt Lake City, UT —  (0.05 mile, 0.015 WL)(b)

  Lifetime chance of fatal cancer              0.03               0.03
  Years of life lost per fatality             15                 25


Grand Junction, CO —  (0.1 mile, 0.045 WL)(b)

  Lifetime chance of fatal cancer              0.01             0.03
  Years of life lost per fatality             15               25


Durango. CO — (0.1 mile, 0.026 WL)(b)

  Lifetime chance of fatal cancer              0.03             0.02
  Years of life lost per fatality             15               25


Rifle. CO — (0.5 mile, 0.007 WL)(b)

  Lifetime chance of fatal cancer              0.008            0.005
  Years of life lost per fatality             15               25


Gunnison.  CO — (0.5 mile, 0.008 WL)(b)

  Lifetime chance of fatal cancer              0.009            0.006
  Years of life lost per fatality             15               25
(a) A risk of 0.03 is the same as 30,000 chances in 1 million, or 30 in
1 thousand.

    The distance and radon concentration including background for the
    nearest resident to the pile (FB 76-78).
                                   . 1-19

-------
radon emissions from inactive piles are below the emission rate of 10,000
curies per year used to compile Table 4-2.  The radon levels listed in
Table 4-3 are based on the site-specific Ford, Bacon and Davis Engineering
Assessments of inactive piles prepared for the Department of Energy
(FB 76-78), and are not directly comparable to the hypothetical cases in
Table 4-2.  Estimates of individual risks for lifetime exposure at sites  in
Table 4-3 are as high as a one-in-25 chance of death from lung cancer.
This  is  considerably greater  than  the  risk from average residential radon,
about 1  in  300  (see below).

      Table  4-4  estimates  the  risks from  the  naturally occurring  radon  decay
 products found  in  ordinary homes  near  neither mill  tailings  nor  any  other
 specifically  identified radon source.  National  data on  radon  decay  products
 in homes is very scanty,  and  varies widely  among individual  houses.   The
 estimates in Table 4-4 assume that the average  concentration is  0.004 WL in
 homes occupied 15% of the time.   The assumed average  level  of  radon  decay
 products is based  on recent  data on 21 houses in New  York and  New Jersey
 (GE 79), and is consistent with data obtained in other countries (UN 77).
 For comparison, the risks estimated in Table 4-4 are  about 10* of the
 expected lifetime risk of lung cancer death from all  causes (0.029)  in a
 stationary population having 1970 U.S. lung cancer mortality rates.


 4*5  RlskS to the Continental U.S. Population from Radon Emitted from
      Inactive Piles
      Radon emissions from tailings piles may affect health beyond the 50
 miles considered above.  We estimated exposure to the U.S. population

                                      4-20

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                                  TABLE 4-4

                         Risk from Background Radon
                          in Residential Structures
                                                  .(a)
Lifetime chance of fatal lung cancer

Years of life lost per fatality

Average days of life lost
   per exposed person
                                                 Estimated Risk
                                                               (b)
Relative

  0.004

 15


 23
Absolute

  0.002


 25


 18
(a)A risk of 0.004 is the same as 4000 chances in 1 million, or 4 in
    1 thousand.

(b)calculated on the basis of 0.004 WL, home occupied 75% of the time,
    and 1970 U.S. mortality rates (EP 78).
                                    4-21

-------
beyond 50 miles using two different models for atmospheric transport.  The
simplest, which treats radon diffusion on the basis of very general wind
patterns, yields an annual collective exposure of 0.65 person-working-level
for each 1000 curies of radon emitted per year to persons living more than
50 miles (80 kilometers) from an inactive pile (SW 80).  A more detailed
meteorological model, developed for EPA by the National Oceanic and
Atmospheric Administration (NOAA), has been used by the Nuclear Regulatory
Commission (NR 79) to calculate the concentration in air of radon emitted
from four sites in the western U.S.  A relationship between outdoor radon
concentration and working level is needed to compare the results of the two
methods.   Assuming that a radon concentration of 100 pCi per liter corres-
ponds to about 0.7 WL (EP 78), the national collective exposure from the
four sites considered in the NRC study ranges from 0.42 to 0.76 person-
working-level per 1000 curies released per year,  with an average of 0.56.
This agrees reasonably well with the results of the less detailed calcula-
tions, and is adopted here.  This collective exposure does not include
people living within 50 miles of a pile.
     Both the EPA and NOAA/HRC assessments assume a continental 0 s
population of 200 minion persona,  based on ,970 U.S.  oensus ^
geographically simUar population dlstrihutlon and a projected 1980
continental population of 220 million would increase the elective
exposure by about 10*.
                                                                    A

                                    M-22

-------
inactive tailings piles.  The radon emissions on which the risk estimates



in Table U-5 are based are calculated  from  the size of the pile and  the



amount of radium per gram of material, assuming a radon-222 emission rate



of 1 pCi/sec for each square meter of  area  and for each pCi of radiura-226



Per gram of tailings (SW 80).  Complete field measurements are unavailable




and actual emissions could be considerably  different from calculated values.








     The total effect for persons living more than 50 miles from the 21




piles in Table 4-5 is summarized in Table M-6, which provides different




measures of health risk.  They represent the total risk over 100 years for



an exposed population of 200 million;  on average, an individual's annual




risk from the model pile is 20 billion times smaller.








U.6  Regional and National Effect from Long Half-Life Radioactive Materials




     Windblown particles and the long  half-life decay products of radon




(beginning with lead-210) are also potential hazards (see Figure 4-1).  The



consequences of eating and breathing long half-life decay products cannot




be established without site-specific information—food sources, for




example.  The only detailed study is one provided for a model active site



in the NRC Draft GEIS on Uranium Milling (NR 79).  As explained below,



however, the NRC results apply in their entirety to few of the inactive




sites.  We use the results of the NRC analysis here only to identify



important exposure routes and to compare their importance to that of the



short half-life decay products of radon.  The results shouldn't be taken as




truly quantitative estimates of the risk at specific inactive sites.








     The NRC model uranium mill and tailings pile is located in a sparsely




populated agricultural area based on cattle ranching.  The population in



                                     M-23

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                                 TABLE 4-5
     Approximate  Contribution oj*Tailing Piles at Inactive Sites to the
              National Health Risk from Radon Decay Products^
    Inactive Site

Monument Valley, Arizona
Tuba City, Arizona

Durango, Colorado
Grand Junction, Colorado
Gunnison, Colorado
Maybell, Colorado
Naturita, Colorado
Rifle, Colorado(c)
Sliok Rock, Colorado(c)

Lowman, Idaho

Ambrosia Lake,  New Mexico
Shiprock, New Mexico

Lakeview, Oregon

Palls City, Texas

Green River, Utah
Mexican Hat, Utah
Salt Lake City, Utah

Converse, Wyoming
Riverton, Wyoming
  Annual Risk of Fatal Cancer
       (deaths per year)
Relative Risk      Absolute Risk
.006
.04
.02
.0?
.02
.04
.03
.06
.03
.005
.1
.04
.02
.1
.01
.065
.15
.003
.07
0.003
0.02
0.01
0.03
0.01
0.02
0.02
0.03
.01
.002
0.05
0.02
.01
.05
0.005
0.03
0.07
0.001
0.03
 (a)Does not include effects within 50 miles of the site.

 (b)Years of life lost and other measures of risk are discussed in
     summary Table 4-6.

 (c)Two inactive piles.
                                      4-24

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                                  TABLE U-6
               Summary Table—Tailings piles at Inactive Sites
                                                             .(a)
      Estimated National Risk of Fatal Lung Cancer from Radon Emissions
                                                                      .(b)
   Inactive Sites

Fatal cancers per 100 years

Increased chance of lung cancer death

Years of life lost per fatality

Average days of life lost
   per exposed person
                                                    Estimated Risk
 Relative
   90
Absolute
0.3/1,000,000    0.1/1,000,000

   15                25
    0.0017
   0.0013
(a)  Canonsburg, PA, site not included.

     Does not include people living within 50 miles of the site.
                                    1-25

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this region produces all of its own food.  Because this scenario maximizes

the dose due to food, it is inappropriate for many of the inactive sites.

For tailings near urban areas, with a large number of people living close

to the tailings pile, complete dependence on locally supplied food is

considerably less likely.



     The five  sources of exposure  in the NRC analysis are shown  in Table

4-7.  The  risk from  breathing short half-life radon decay products is more

than  10 times  greater than the next highest risk, that  due  to windblown

tailings eaten in vegetables and meat.d)  Lead-210 and polonium-210,

formed in  air  following radon  decay, are also a  source  of exposure when

deposited  on  food or breathed.  According  to  the NRC  analysis,  the  risk

from  each  of  these  pathways  equals about one-hundredth  of the risk  from

breathing  short  half-life  radon  decay  products.   Even combined, the total

risk from  the long  half-life radionuolides is much less than the risk from

 breathing the short half-life radon  decay  products.   Persons living more

 than 50 miles from an inactive pile  would be less heavily exposed and their

 risk would be considerably below that indicated in Table U-7.



 4.7 Impact from Gamma-Ray Exposure

      Many of  the radioactive materials  in tailings piles are a  source  of

 gamma rays.   Unlike alpha rays, which must originate within the body to
  O)The NRC analysis  for  the  ingestion  pathway  is  quite  conservative
  because  the retention  on vegetation assumed  for deposited  materials (50*),
  and the  transfer of  radium from fodder to  meat (.003) are  larger by a
  factor of five or more than  is  usually assumed (EP  78a, MC 79),
                                      4-26

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                                 TABLE M-7

                 Regional Impact from Uranium Mill Tailings

                    (NRC-GEIS Model Pile  and Population)
                     Population at Risk—57,300 persons
                                              Number of Cancer
                                               Deaths Per Year
Inhaled radon decay products

Ingestion of windblown tailings

Inhaled lead-210/polonium-210

Ingested lead-210/polonium-210

Inhaled resuspended tailings
.06(a)

.004(b)(c)

.0006(b)

.0006(b)

.00006(b)
         the computed data for/individual radionuclides used to produce
  —a_3ummarytables.in the'NRC-GEIS (NR 79).	   .	„
<<0  Particles containing U-238, U-234, Th-234, Th-230, Ra-226, Pb-210,
     Bi-210; c.f. Fig. 4.1
                                    4-27

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become hazardous, gamma rays can penetrate both air and tissue for
considerable distances.  Near the edge of a pile, the exposure from gamma
rays can be many times larger than the background level of gamma rays in
uncontaminated areas.  The concentration of gamma radiation from the pile,
however, decreases rapidly with distance; at more than a few tenths of a
mile from moat of the inactive tailings piles, it is undetectable above
normal background.

     Gamma ray exposures to individuals depend on how close to the edge of
a pile people live or work.  The collective gamma ray dose depends on both
the number of people exposed and their average dose.  In a few cases indi-
vidual doses can be approximated from available  data, but generally this
cannot be done without a variety of information, such as where people live
and work and the amount of shielding provided by buildings.  Outdoor gamma
ray exposures in the vicinity of some tailings piles at inactive sites are
summarized in Table 4-8.  In several cases, even the nearest residents are
far enough from  the pile that they receive essentially no excess gamma
radiation.  At others, a few residents are located  close enough to perhaps
double the dose  from gamma radiation that would  occur without the pile.   In
a few cases, the dose  to the nearest resident may be several times normal
background levels.

     In most of  these  localities, "normal" background due to penetrating
radiation is about 100 mR per year (FB 76-78}.(1)   This radiation exposes
 (1)A milliroentgen  (mR), or  one  one-thousandth of a Roentgen,  is  a unit
 of  radiation exnosnr*«.
of radiation exposure.
                                     K-28

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                                    TABLE 4-8

                         Increased Gamma Ray Dose Rates
                      From Tailings Piles at Inactive Sites
                                                          .(a)
     Site

Durango, CO
Grand Junction, CO
Gunnison, CO
Rifle, CO

Lowman, ID

Ambrosia Lake, NM

Canonsburg, PA

Green River, UT
Salt Lake City, UT

Spook, WY
Location of Nearest Resident
  Distance from Pile Edge
          (miles)
Annual Gamma Ray
   Exposure(b)
      (mR/yr)
0.1
0.1
0.5
0.25
1.0
1.5
0.04
0.15
0.05
200-300
580
— (c)
-(c)
— (c)
-(c)
150
-(c)
465
            1.5
       -(c)
(a)Ambient gamma ray background at each site has been subtracted.

(b)Measured in air (Roentgens).  At these energies continual exposure to
   1  mR/yr gives an annual dose of 1 mrem.

(°)No detectable increase above background.
                                    4-29

-------
the total body, so that all organs are at risk.  The estimated frequency  of
fatal cancer and serious genetic effects due to a lifetime exposure of  100
mR per year is listed in Tables 4-9 and 4-10.  People who live or work  near
tailings piles will incur higher risks from long-term exposures than those
listed in the tables in proportion to the excess of their annual dose rate
above 100 mR per year.

     In summary, information does not allow calculation of the collective
gamma ray dose and risk to all persons living or working near the inactive
piles, but the total impact is small because the gamma-ray intensity falls
rapidly with distance from the pile.

4-8 Hazard from Water Contamination
4.8.1 Introduction
     Evaluating the potential effects of nonradioactive toxic substances in
tailings requires different methods than those used for radioactive
substances.  The basis for radiation risk estimates is that all ionizing
radiation can produce cancer, and that the probability increases with the
dose.d)  With nonradioactive toxic materials, however, where the effect
varies with the material, and the severity of the effect-but not its
probability of occurring-increases with the dose, a classical analysis of
toxicity is used.  Moreover, because the body can detoxify some materials
(DMany nonradioactive substances can induce ean^r* <«
animals (GO 77, VE 78).  However  for n««~^    ?!  in exPerimental
uranium mill tailings, we dTnot'            °   iVS substances found in
adequate for estimating risks for
                                    4-30

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                                 TABLE 4-9

                Estimated Lifetime Risk of Fatal Cancer from

                 Total Body Gamma-ray Exposure  at 100 mR/y


                                                Estimated Risk(a)
Lifetime chance of fatal cancer

Years of life lost per fatality(b)

Average days of life lost
     per exposed person
Relative

5 in 1000

 14


 24
 Absolute

.8 in 1000

  23
(a)Lifetime risk plateau.

(b)Based on a normal life  span of 70.7 years,
                                   4-31

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                                TABLE H-10

              Estimated  Risk of  Serious Genetic Abnormalities

                   From Gonadal Dose of 100 mR per year


                                       First              All  Succeeding
                                     Generation             Generations	

Risk per 1000 live births            O.OU to 0.6              0.1*1 to 5


Currently observed in U.S.A.           60 to 100
(per 1000 live births)
                                      H-32

-------
or repair the effects of small doses, often no toxic effects occur below
threshold doses.  With radiation, on the other hand, we assume there is no
dose below which effects do not occur.

     Because of these differences, we cannot construct a numerical risk
assessment for nonradioactive toxic substances.  We can, however,
qualitatively describe the risks of toxic substances in terms of their
likelihood of reaching people (or animals, or agricultural products);
concentrations at which they may be harmful; and their toxic effects.

4.8.2 Movement of Toxic Chemicals from Tailings
     Tailings can contaminate both surface and ground water.  Wind erosion,
floods, tailings slides into adjacent streams, seepage through the pile, or
runoff of rainwater all may cause surface water contamination.  Ground
water contamination can occur only through seepage into an underlying
aquifer (a water-bearing layer of permeable rock).  Since people may draw
water from a single underground source at many different places, exposure
to toxic chemicals greatly depends on the way the contaminants move.  Since
their movement through lakes and streams is familiar, the following
discusses movement of dissolved contaminants in the ground.

     Not enough information is available to estimate the chance that toxic
substances from tailings will move through water and expose people to
them.  Migration of these substances in ground water near tailings piles,
however, has been observed.  Chemical and hydrological principles can
                                     4-33

-------
identify substances generally most likely to enter and be carried through
ground water, though the specific substances will vary among the sites.

     Some organic compounds—amines, kerosene and higher alcohols, for
example—are present in tailings from acid leach mills.  But the main
long-term ground water hazard is from leached inorganic toxic substances
and radioisotopes.  Movement of contaminants to ground water depends on
complex chemical and physical properties of the underground environment,
and on such climate conditions as precipitation and evaporation.  Chemical
and physical processes in the subsoil remove a portion of some contaminants
from water passing through it.  Contaminants including selenium, arsenic,
and molybdenun, however, can occur in forms which are not removed.

     Studies of leaching at tailings piles (DR 78) and leachates from
municipal land fills  (EP ?8b) help determine which substances generally
will be relatively mobile or immobile, and which will have a mobility which
varies with local conditions (EP ?8c).  Limited studies of pollutant
migration into ground water near tailings piles tend to confirm estimates
using other methods of elements that will be most mobile  (FB 76-78, KA 76,
DA 77).  There has been no systematic study, however, to  establish the
magnitude of ground water contamination for tailings at either active or
inactive sites.

     Based on available information, chromium, mercury, nickel, arsenic,
beryllium, cadmium, selenium, vanadium, zinc, and uranium have a high
probability of being  mobile.  Lead, radium, and polonium are not predicted

-------
to be mobile near tailings piles, but they appear to be mobile at some
locations.  Data to suggest or confirm mobilities near tailings piles for
the other toxic elements are not available, but conservative assumptions
should be used for ions which are generally mobile, such as nitrate,
chloride, and sulfate.  Certain anions (of arsenic, manganese, molybdenum,
and selenium, for example) and organic complexes of trace metals may also
be relatively mobile, although confirming field data from tailing pile
studies are extremely limited.  If, however, seepage of substances known to
have high mobility is appreciably prevented or reduced, then it would seem
logical that those for which no data are available should also be
controlled.

     When contaminated water from tailings reaches ground water, some
mixing generally will occur.  Except in very coarse or cracked media,
through which contaminants flow relatively unimpeded, concentrations of
contaminants reaching ground water will likely be reduced along the flow
path by dispersion, and by absorption, adsorption, and ion exchange with
the ground material.  The level of users' exposure to contaminated ground
water depends on the amount consumed as well as the level of contamination.
Consumption depends on the palatability and quality of the water, the
purposes for which it is used, and the number of users.  Available data
indicate that tailings have contaminated some private wells in the Grant's
Mineral Belt in New Mexico (KA 76) with toxic substances whose concentra-
tions greatly exceed the National Interim Primary Drinking Water
Regulations that apply to public drinking water supplies (EP 76a).
                                     4-35

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4.8.3 Tpxicity of Major Toxic Substances Found in Tailings




     There is little data to estimate the probability or the level of




exposure to contaminated water, but reasonably good information exists on




its potential toxic effects.  No acute effects—death in minutes or hours—




could occur except by drinking liquid direct from a tailings pond.  Severe




sickness,  or death within days to weeks, from the use of contaminated




ground water is possible, but unlikely.









     Chronic toxicity,  from  the continuous  consumption  of  contaminants  at




rather  low concentrations, could be  a problem.  Toxic substances can




accumulate slowly in  tissues,  causing symptoms  only after  some  minimum




amount  has accumulated.   Symptoms  of chronic  toxicity develop slowly, over




months  or years.








      Tables 3-2  and 3-3 list many  chemical  elements and ions that  have  been




 found in tailings piles.  Many of these occur in tailings in only slightly




 higher concentrations than in  background soils  and also have low toxicity




 when taken orally (VE 78):  lanthanides, including cerium, europium,




 lanthanum, and terbium; silicates; and  zirconium,  scandium, boron, gallium,




 and aluminum.  Some other elements may be in elevated concentrations in




 tailings, but they too are not very toxic:   copper, manganese,  magnesium,




 cobalt, iron, vanadium, zinc, potassium, chloride, and sulfate.  Some of




 these elements an.d ions will also cause water to have an objectionable taste




 and color we-MrlSelow concentration  levels that are toxic to humans and




 animals:   iron,  copper, manganese,  chloride, and sulfate.
                                      4-36

-------
     Cyanide has a high oral toxicity in humans and animals, and has been




found in uranium mill tailings.  Once it is released to the ground, however,



it is expected to be oxydized to the nitrate form, which is much less toxic




(NA 77).








     Other substances are both present in tailings and are regulated under




the National Interim Primary Drinking Water Regulations (NIPDWR).  Listing




in the NIPDWR is an indication of a significant need to limit direct human




consumption of these substances.  The NIPDWR cover the inorganic chemicals




arsenic, barium, cadmium, chromium, lead, mercury, nitrate, selenium, and



silver.  The toxicologies of these substances are discussed in Appendix C.




Fluoride is also covered by the NIPDWR,  but has not been reported as present




in tailings.  Molybdenum, though not included in the NIPDWR, is both toxic




and present in tailings in elevated concentrations; its toxicity is dis-




cussed in Appendix C.  Tailings also contain elevated levels of naturally




radioactive substances, such as radium,  thorium, uranium,  and their decay




products.  Appendix C discusses both the chemical and radiological toxic




effects of ingesting radium, thorium, and uranium.








     Tailings are not significant sources of other toxic materials that are




regulated in the NIPDWR, such as organic substances, microbiological organ-




isms, and man-made radioactivity.








4.9  Conclusions




     At many of the inactive mill sites, health risk to individuals is




increased because of inhaled radon decay products (c.f. Tables 4-3 and 4-4)






                                     4-37

-------
and gamma ray exposures from tailings.  Table 4-11 summarizes the local,




regional, and national risks due to radon decay products from the inactive




sites.  In preparing Table 4-11, we have supplemented the data presented




elsewhere in this chapter with other analyses of population exposure from




tailings piles (FB 76-78) so as to include all sites.  All of these




estimates are based on current populations and therefore will change with




population growth as well as living patterns.  At present, most of the




potential effect is projected to occur in the regions near the inactive




tailings pile.  The national effect, however, is comparable.








     Compared to the risk from short half-life radon decay products  (see




Table 4-11), the other radiological risks are much less  significant.  At




most, they increase by 10%  the risk estimated for the regional population,




and  the  risk to  the national  population  is much  less.   This  incremental




risk is  small compared to the uncertainty—at least  a factor  of  two—in  the




estimated risk  for  lung  cancer  death  from the  short  half-life radon  decay




products.









      The nonradioactive  toxic  substances present in  an  inactive  tailings




 pile and their  potential impact on public health and the environment must




 be determined  for  each site.   Those substances  which can move through




 ground water and which have the greatest potential toxicity include arsenic,




 barium,  cadmium, silver, chromium, lead, mercury, molybdenum, selenium,




 nitrate, iron, and vanadium.  In addition, among radioactive substances,




 uranium is most likely to be mobile in ground water, and radium and




 polonium are possibly mobile.






                                      4-38

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                                  TABLE 4-11

  Summary— Risks from-Radon Emitted from Tailings Piles at Inactive Sites

                    (Short  Half-Life Radon Decay Products)


                               Estimated-Fatal Cancers (per 100 years)
                              Relative Risk               Absolute Rxsk
                                 Model                        Model

Deaths occurring within
  50 miles of site                150                          130

Deaths occurring more than
  50 miles from site              J2£                          -12

     TOTAL                        240                          170
                                    4-39

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                          References for-Chapter 4

(AR 79)   Archer,  V.E.,  "Factors  in  Exposure Response Relationships  of  Radon
         Daughter Injury,"  Proceedings  of  the  Mine  Safety  and Health
         Administration, Workshop on lung  Cancer  Epidemiology and
         Industrial Applications of Sputum Cytology, November 14-16,  1978,
         Colorado School of Mines Press, Golden,  Colorado  (1979).

(CO 78)   Cook, J.C., Bunger, B.M.,  Barrick, M.K., "A Computer Code  for
         Cohort Analysis of Increased Risks of Death,"  CSD/ORP  Technical
         Report No. 520/4-78-012, USEPA, Washington, D.C.  (1978).

(DA 77)   D'Appolonia Consulting  Engineers, Report 3» Environmental  Effect^
         of Present and Proposed Tailings  Disposal Practices, SplitRoctc
         Mill, Jeffery City, Wyoming,  Volumes  I and II.   Project No.  SM
         77-419 (1977).

(DR 78)   Dreesen, D.R., Marple,  M.L.,  and  Kelley, N.E.,   Contaminant
         Transport, Revegetation,  and Trace Element Studies at  Inactive
         Uranium Mill Tailings Piles,  pp.  111-139 in Proceedings of the
         Symposium on Uranium Mill  Tailings Management,  Colorado State
         University, Fort  Collins,  Colorado (1978).

(EP 76)  EPA Policy Statement on the Relationship Between Radiation Dose
         and Effect, 41 F.R. 28409, July 9,  1976.

(EP 76a) Environmental Protection Agency.  National Interim Primary
         Drinking Water Regulations, EPA-570/9-76-003.  USEPA,  Office of
         Water Supply, Washington, D.C. (1976).

(EP 78)  "Indoor Radiation  Exposure Due to Radium-226 in Florida Phosphate
         Lands."   EPA  520/4-78-013, U.S.  EPA, Washington, D.C.  (July  1979).

(EP 78a) "Response to  Comments; Guidance  on Dose Limits for Persons Exposed
         to Transuranium Elements  in the  General Environment,"  EPA
         520/4-78-010, U.S.  EPA, Washington,  D.C.  (1978).

 (EP 78b) Investigation of  Landfill Leachate Pollutant Attenuation  by  Soils»
         EPA-600/2-78-158.USEPA, Municipal  Environmental Research
         Laboratory, Cincinnati, Ohio  (1978).

 (EP 78c) Attenuation of Pollutants-in  Municipal  Landfill•Leachate  by  Clay
         Hinerals, ^PA-600/2-78-157, tfSEPA, Municipal Environmental
         Research  Laboratory, Cincinnati, Ohio (1978).

 (FB 76-78)    Ford, Bacon and Davis Utah, Inc.,  Phase II-Title  I
               Engineering Assessment  of Inactive Uranium  Mill Tailings, DOE
               Contract •:No.~E(05-l)-165li,  Department  of  Energy,  Washington,
               D.C. (1976-78).
                                     4-40

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(GE 78)  George,  A.C.  and Breslin,  A.J.,  "Distribution of Ambient  Radon and
         Radon Daughters in New York and  New Jersey Residences,"
         Proceedings of Natural Radiation-Environment  III,  April 23-28,
         1978 tto be published!, University of Texas,  Houston,  Texas.

(GO 77)  Goyer, R.A. and Mehlman, M.A.  editors,  Toxicology of-Trace
         Elements,  Advances in Modern Toxicology,  Vol. 2.  John Wiley  &
         Sons, New York (1977).

(KA 76)  Kaufman, R.F., Eadie, G.G.,  and  Russell,  C.R.,  "Effects of  Uranium
         Mining and Milling on Ground Water in the Grants Mineral  Belt,  New
         Mexico,"  Ground Water 14;296-308 (1976).
                                                                       /
(NA 77)  National Academy of Sciences,  Drinking Water  and Healthy  Part 1»
         Chapters 1-5, NAS Advisory Center on Toxicology, Assembly of  Life
         Sciences,  Washington, D.C. (1977).

(NR 79)  Draft Generic Environmental  Impact Statement  on Uranium Milling,
         Volume II, NUREG-0511, U.S.  Nuclear Regulatory Commission,
         Washington, D.C. (1979).

(SW 80)  Swift, J.J. "Distant Health  Risks from Uranium Mill  Tailings
         Radon," U.S.  EPA, Office of Radiation Programs, Technical Note
         ORP/TAD-80-1, 1980 (to be  published).

(UN 77)  "Sources and Effects of Ionizing Radiation,"  United-Nations
         Scientific Committee on the  Effects of Atomic Radiation,  1977,
         Report to the General Assembly,  U.N. Publication E.77.IX.1,
         United Nations, NY.

(VE 78)  Venugopal, B. and Luckey,  T.D.,  Metal Toxici ty_ in Mammals .2>
         Chemical Toxicity of Metals  and  Metaloids, Plenum Press,  New  York
         (1978).
                                    4-41

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               5:  ALTERNATIVE TAILINGS DISPOSAL CONTROL LEVELS



 5.1  Introduction




      Generally applicable standards to protect the public  health  and  safety




 and the environment  must consider reasonable and  feasible  methods of




 controlling uranium  mill tailings.   The longevity of control methods  is




 important,  because radioactive  contaminants  have  long lifetimes and




 nonradioactive contaminants  are  permanently  toxic.








      The predominant health  hazard  of  tailings is  from radon-222  released




 into the atmosphere.  Techniques  providing reasonable  long-term control of



 radon also  provide nearly complete  control of  particulate  releases and




 direct  gamma radiation.   This chapter discusses control of radon-222 and




 the  water pathway, and longevity  of  control.








      The degree of radon  control  that we could require ranges from none




 (leaving the sites as they are) to nearly total (little or no radon release




 from tailings).  The following compares three degrees of control for their




 costs, benefits, feasibility, longevity, and other considerations in



developing an appropriate standard;




     a.   No control  (the existing situation).




     b.   Radon releases  controlled at various levels down to about the




natural  background rate.




     c.   Complete  control (practically  no release).

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     For potential water contamination, control alternatives similarly




range from none to total.   The control levels examined are:




     a.  No control (the existing situation).




     b.  Control comparable to other water quality programs.




     c.  Complete control (no contamination).








     Ultimately, health protection will depend on the time over which




controls are maintained as well as  the degree.  We examined the technical




and  economic reasonability of requiring effective control for the following




periods:




     a.  Several hundred years.




     b.  Hundreds  to  thousands  of years.




     c.  Longer than  tens  of  thousands  of years.








 5.2  Control of Radon-222  Releases




      Radon release control methods  range  from a simple barrier  between the




 tailings and the atmosphere to such ambitious treatments as embedding




 tailings in cement or processing them to remove the radon sources.




 Barriers should be able to resist wind and water erosion and human




 intrusion.  Radon control  techniques and estimates for various levels of




 control are discussed more fully in Appendix B.  A general discussion of




 radon control  and the ancillary benefits  of controlling other potential




 hazard pathways follows.
                                       5-2

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5.2.1  Radon Control



     Radon-222 releases into the atmosphere can be controlled by covering




the tailings with an impermeable barrier, like plastic, or by enough




permeable material, like soil, to slow down the radon passing through so




that the amount of radon released is reduced because of radioactive decay.




Generally, the more permeable the covering material, the thicker it must be




for a given reduction in radon release.  Maintaining the integrity of thin




impermeable covers over periods even as short as tens to hundreds of years,




however,  is highly uncertain  under  the likely range of chemical and




physical  stresses.








     Natural materials  can be used, such as soil, clay, gravel, or a




combination.   Clay-type material, especially  when moist,  generally resists




the  passage of radon much more  than an equal  thickness of  soil  or sand.




The  half-value-layer  (HVL)  is that  thickness  of cover  material  which




reduces the radon release  to  one-half  its  uncovered value.   Table  5-1  shows




 the  approximate HVL of typical  natural materials for reducing radon




 releases.  These HVL values are nominal;  HVLs at actual  sites depend on




 soil composition, compaction, moisture present, and other factors.









      Figure 5-1 shows nominal curves  for the percentage of radon which




 would penetrate various thicknesses of different materials (FB 76-78).




 Using the HVL concept, about seven HVLs  of cover reduces radon releases to




 less than 1%  of  the uncovered rate, and about  10 HVLs reduce the release to




 less than 0.1%.  Radon reductions are multiplicative for HVLs of the same
                                      5-3

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                                  TABLE 5-1
         Nominal Half-Value-Layers of Typical Natural





          Materials for Reducing Radon






      Material




Sandy, porous soil




Mid-range, typical Western soil




Well compacted, moist soil




Moist clay
                                                   HVL




                                                1.0 meters




                                                0.5 meters




                                                0.3 meters




                                                0.12 meters
(a)
   From (MR 79)  Appendix K,  Chapter  9  and  12.
                                    5-4

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                         FIGURE 5-1
100
                                 A=SANDY SOIL (HVL = 1.0 M)
                                 B = SOIL (HVL = 0.5 M)
                                 C = COMPACTED, MOIST SOIL
                                               (HVL=0.3 M)
                                 D=CLAY(HVL=0.12 M)
                    2345
                     COVER THICKNESS (METERS)
6
                                 5-5

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or different materials.  For example, one HVL of soil plus one HVL of clay
reduce radon releases to 25% of the uncovered value (50% x 50% • 25%).

     Uranium mills are generally located near the mines where the ore is
obtained, and often other mines are nearby.   Disposing tailings in these
mines should be seriously considered.  The thick cover and erosion protec-
tion would almost completely control radon emission for substantially
longer than could generally be expected using above-grade disposal methods.
Since mines are usually below the water table, however, elaborate and costly
ground water protection methods might be needed, and it is not clear  that
effective methods are known.  There will be transportation hazards and
coats.   Even where otherwise suitable mines are near an inactive processing
site, using them for tailings disposal might make  future development  of the
mine's residual resources impossible.

5.2.2  Effects of Radon Control on Release of Airborne Particulates
     Methods that  control radon will also control  releases of  airborne
particulates.  Either  a  thin impermeable cover  or  a  thicker natural
material cover will  prevent particulates  from becoming windborne.  Any
covering will prevent  the spread of windblown tailings as long as the
integrity of that  cover  is  maintained.  Therefore, assuming that  some
control  of radon release will be required, control of  airborne particulates
needs  no further  discussion.
                                      5-6

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5.2.3  Effects of Radon Control on Direct Gamma Radiation




     Covering tailings piles to reduce radon-222 releases will also reduce




direct radiation.  As with radon, attenuation of gamma radiation depends on




the thickness of the cover.  Figure 5-2 shows the nominal percentage of




gamma radiation that will pass through a given thickness of compacted soil.




The HVL of compacted soil is about 0.1 meters.  Soil compaction, moisture




content, type of soil, and other parameters all are factors.  A thin,




impermeable cover, such as a plastic sheet, will reduce gamma radiation




insignificantly.  A thicker cover of a material such as soil will provide




significant reduction.  Comparing the HVLs of soil for reduction of radon




releases and reduction of gamma radiation, coverings of soil-like material




thick enough to significantly reduce radon emissions will greatly reduce




gamma radiation.  Again, assuming that some radon control will be required,




direct gamma radiation exposure from tailings piles will be addressed no




further.








5.2.4  Effects of Radon Control on Potential Water Contamination




     Covering uranium mill tailings piles to reduce radon-222 releases can




also help to control potential contamination of surface and ground water.




A cover will prevent the wind from blowing tailings directly or indirectly




into surface water, and may control erosion caused by precipitation, runoff,




or streams.  The proper cover can reduce infiltration of precipitation into




the piles.   A thin, impermeable cover would prevent all infiltration, so




long as the cover remained intact.  A thicker cover of natural materials,




especially if clay-like and shaped as a dome, might provide an infiltration




barrier and encourage run-off.






                                     5-7

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100
                           FIGURE 5-2
                                         COMPACTED SOIL
                                                 (HVL = 0.1 M)
                   0-2       0.3       0.4      0.5
                    COVER THICKNESS {METERS)
0.6
0.7
                             5-8

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     Covering tailings below ground in specially-dug pits, open pit mines,




or underground mines—can greatly help to control surface water contamin-



ation by reducing erosion.  Care must be taken, however, not to contaminate




useable ground water with radioactive and nonradioactive pollutants.








5.3  Control of Surface and Ground Water Contamination



     A suitable cover can prevent surface water from being contaminated by




windblown tailings.  Control of erosion caused by streams or precipitation




could consist of contouring and covering the pile and stabilizing the




surface—that is, making it resistant to erosion.  If necessary, the pile




could be moved to a site away from existing streams and then covered.  A




suitable cover can reduce leaching of contaminants caused by precipitation




that soaks into the pile.








     Ground water contamination, caused by direct contact with the tailings




and leaching of the radioactive and nonradioactive contaminants, may be the




most difficult problem.  There are two general approaches to limiting




direct contact with groundwater.  First, the tailings can be placed far




enough above the water table and its predicted fluctuations to avoid



contact.  Second, an  impermeable barrier would be imposed between the




tailings and the ground water.  In some cases, to make  these control




approaches feasible and long-lasting, the pile must be moved.  Some of the




existing tailings sites may already be in a suitable position above the




water table.  At other sites, however, continuous contact with ground




water, or periodic contact as the water table fluctuates, occurs.
                                     5-9

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     Ground water  contaminant  concentrations near  the  inactive mills  were




surveyed as part of the  Phase  II studies  (FB 76-78), and  case histories of




some water contamination problems  near  uranium mills and  mines are  given in




a report prepared for EPA (GE  78).  There is evidence  that ground water




near some inactive sites is  already contaminated,  probably due to seepage




of liquids from tailings ponds during and after their  active use.  Such




seepage may now have slowed, because the  tailings  ponds at inactive sites




have partially dried up.  However, leaching by precipitation that infil-




trates uncovered tailings piles is still  a possibility.









     Recent studies by Markos (MA  79) of tailings at inactive 'sites suggest




that soluble contaminants sometimes move to the surface of the  piles rather




than to  the ground.   If  confirmed,  these studies would suggest that ground




water  contamination by  long-term  leaching is less likely than it might  seem.




The processes  that carry substances  upward through the piles, however,  might




also cause them to penetrate  cover materials.  If this should happen,  these




substances would  then be carried  off the  site by wind  and  precipitation.




Although the potential  effects  of such processes have not  been assessed,




 contamination  of surface water  appears to be  possible.   Disposal system




 designers will have to  consider the potential effects  of such contaminant




 transport processes in  choosing suitable disposal concepts, materials, and




 sites.  At present, it  is unclear what methods,  if any,  may be needed




 specifically to avoid harm to the environment and public health  from




 upwardly mobile soluble contaminants.
                                      5-10

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     Proper disposal of tailings piles should prevent or reduce




contamination from new releases.  However,  water supplies could become




contaminated in the near or distant future  by toxic materials that are




already on their way to an aquifer.  These  substances may move slowly




through the ground.  Ground water itself can move slower than a few feet pei




year, and only in coarse or cracked materials does the speed  exceed one mile




per year.  For these reasons, pollutants released from tailings may not




affect the quality of nearby water .supplies for decades or longer.   However,




once polluted, the quality of such water supplies cannot be quickly restored




by eliminating the source of pollutants. Even if a pile is disposed of so




there is no further seepage, it may take nature longer to restore the




original water quality throughout the affected area than the  time from the




start of the pile to the first contamination of water supplies.









     Toxic substances released from a pile  but not yet in contact with an




aquifer could be very difficult to trace and remove.  A recent report pre-




pared for EPA (JR 80) reviews methods that  sometimes can improve the quality




of an already contaminated aquifer.  The economic and technical practicality




of achieving any preset degree of cleanup is uncertain, however, especially




for  general application at all  sites.  The only feasible generally applic-




able control would be to monitor the quality of the aquifer and limit the




use  of  its water.  How long  this may be necessary depends on  the degree of




contamination, the rate of ground water movement, the amount of dilution




and  dispersion taking place, and the intended use of  the water.
                                     5-11

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5.4  Longevity of Control



     The longevity or permanence of any control  methods  used  is  of prime



concern.  Because of the long lifetimes of the radioactive contaminants




(thorium-230 has a half-life of about 80,000 years) and the presence of



other  toxic chemicals  (which never decay), the  potential for harming people




and  the environment will persist indefinitely.  The ultimate objective  of a



 disposal  program is  not only  to reduce the potential hazards  to an accep-




 table level  now, but also  to  control these potential hazards  for as long as




 their source persists.








       This section examines the pertinent technical and social factors  that




 influence the  choice  of periods for applying pollution control  standards




 for tailings  disposal.








  5.4.1  Effects of Natural Forces



       Natural forces may  disrupt attempts to isolate radioactive waste, as




  several authors have discussed (EP 78, GS 78,  LU 78,  NE 78, GS 80).  The




  factors affecting long-term performance are numerous  and interrelated, and




  include some  over which  people may have no influence.  Our general belief




  is that stability  against natural  forces could reasonably be expected for a



   few hundred  to a few thousand years  by  dealing with the  problem  on a  c*se-




   by-case basis and  taking site-specific  factors  into account.   Predictions



   of stability become less certain as the time  period  increases.  Beyond




   several thousand years,  long-term geological  processes  and climatic  change




   will determine the effectiveness of most "permanent" control  methods.




   Glaciation, volcanism,  uplifting and denuding of the Earth's  surface, and






                                        5-12

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deposition of material  have occurred during the past 100,000 years and will




continue.



     In a  report for Argonne National Laboratories,  "Evaluation of Long-Term




Stability of. Uranium Mill Tailing Disposal Alternatives" (KE 78), Nelson and




Shepherd considered the impact of natural phenomena, including earthquakes,




floods, windstorms, tornadoes, and glaciers.  These events could disperse




the tailings, making possible chronic exposure to their radioactive and




nonradioactive toxic constituents.  The following comments are summarized





from their report.








5.4.1.1  Earthquakes



     Earthquakes can damage caps and covers, as well as disrupt barriers




under  disposal  sites.  The number and magnitude of  past earthquakes in  an




area suggest  the probability of earthquakes in the  future.  As with any




natural phenomenon,  the  confidence  in such predictions rises  as  the time




period for which reliable earthquake and  faulting information  is  available




increases.   The  likelihood  that  controls  will  fail  because  of an earthquake




depends on the  chance  of an earthquake  greater than that in  the  design




model. Even if a  disposal  plan  is  designed on the  basis of  the  maximum




credible  earthquake,  there  is  always  the  chance of  a larger  one.   If  an




earthquake occurs  at a site,  the likelihood that  controls will fail will




generally be high.  The  quantity of tailings  released, however,  may be




 small.
                                      5-13

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5.4.1.2  Floods




     Flooding can result  from large  rainstorms,  rapidly  melting  snow,  or




local cloudbursts.  The. erosion floods cause can impair tailings control.




Increased soil moisture from flooding may also make slopes  unstable and




lead to landslides.  Flooding frequency and the "maximum probable flood"




are predictable from historical stream flow data and hydro-meteorological




data.  Over  extremely  long  time periods, however, even the maximum probable




flood  can be  exceeded.  With changes in climate, the frequency of floods




and  the maximum  probable  flood may  change.  Floods  are not time-dependent;




two  large  floods  can occur  in  successive years, though the probability  is




slight.   The effects of  floods can  be  cumulative  if maintenance  or




corrective action is not  employed.









 5.4.1.3  Windstorms and  Tornadoes




      The frequency and intensity of windstorms and tornadoes  are histor-




 ically predictable.  Such predictions, however, suffer from the same




 uncertainties as earthquake and  flood predictions.  The primary impact on




 tailings piles would be wind erosion of the cover or of the material itself.




 With a suitable cover or cap on the tailings, and protection of the surface




 against wind erosion, winds and  tornadoes should have little effect.








 5.4.1.4  Glaciation




       Glaciers occur in mountain  valleys and  as ice  sheets, such as in




 Greenland.   Because of  the magnitude  of the  forces associated with glaci-




 ation,  no portion of  a  surface  depository would  be likely  to survive  even  a




  small,  relatively short-term glacier.  The likelihood  of  continental






                                       5-14

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glaciation in the Western U.S., even far into the future, is remote.  No




evidence exists of continental glaciation south  or west  of the  Missouri




River.  Increased valley glaciation in the west is a possibility, however.




Several glaciers exist high 5n the Rocky Mountains, and  heavy glacial




activity existed in the mountains as recently as 10,000 years ago.  Increase




in valley glaciation is likely over the long term.  Previously  glaciated




mountain valleys are less desirable as disposal sites than nonglaciated




sites, such as flat terrain or valleys created entirely  be erosion.   The




possibility of valley glaciation should he considered in choosing surface




or below-ground disposal methods.









5*^*2  Effects oj^Huma n_Ac tivity




     Disruption of tailings isolation by people is also  a possibility.  The




NRC has discussed the problem (in Chapter 9 of the DCEIS), especially the




need for land use controls.  Building atop a disposal site, excavating or




drilling, or using the surface land for grazing and tilling could disrupt




controls or accelerate natural erosion processes.  Tt has been  suggested




that a disposal site should not be made more attractive to human or animal




habitation than the surrounding environs, and perhaps it should be less




attractive to discourage potential future occupancy (SH 78).









     PL 95-604 requires that final disposal, sites for residual  radioactive




material be owned by an agency of the Federal Government and licensed by the




NRC (42 USC 7901).  Such Federal responsibility should provide  control of




any human activity which might disrupt isolation of the tailings for as long
                                     5-15

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as that responsibility is exercised.  From a historical perspective,




however, we should not expect institutions to perform such functions for




more than a few centuries (RO 77, SC 77, EP 78a, BI 78, LU78).  In  its




proposed criteria for management of radioactive wastes (FR 78), EPA stated




that one should not plan to  rely on institutional controls for more than




100 years.         During the period of effective institutional control, it




should be  possible  to detect and remedy the minor effect  of natural force,s,




such as wind  or water erosion.  This should provide some  assurance  of




continued  stability against  natural  forces  for a  longer  period of time.




Selecting  disposal  sites to  isolate  tailings  from expected habitation  and




 land-use patterns,  at remote location or deep underground locations,  or




both,  is one way to protect  against degradation and  intrusion by  human




 activity after institutional control  has become ineffective.
                                      5-16

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                          References  for Chapter 5


(BI 78)     Bishop,  W.P., et al., May 1978,  "Proposed Goals for Radioactive
            Waste Management,TrU.S. Nuclear Regulatory Commission,
            NUREG-0300.

(EP 78)     U.S. Environmental Protection Agency,  June 1978,  "State of
            Geological Knowledge Regarding Potential Transport of High-^
            Level Radioactive Waste From Deep Continental Repositories,"
            Report EPA 520/4-78-004.

(EP 78a)    U.S. Environmental Protection Agency,  February 1978,
            "Considerations of Environmental Protection Criteria for
            Radioactive Waste."

(FB 76-78)  Ford, Bacon, and Davis, Utah,  Inc., "Phase II-Title 1,
            Engineering Assessment of Inactive Uranium Mill Tailings,
            20 Contract reports for Department of  Energy Contract
            No. E(05-l)-1658, 1976-1978.

(FR 78)     Federal  Register, 43 F.R. 53262-53267, November 15, 1978.

(GE 78)     Geraghty and Miller, Inc., "Surface Impoundments and Their
            Effects  on Ground-Water Quality in the United States — A
            Preliminary Survey," report prepared for the U.S. Environ-
            mental Protection Agency, EPA 570/9-78-004, June 1978.

(GS 78)     U.S. Geological Survey, 1978, "Geologic Disposal of High-Level
            Radioactive Wastes — Earth-Science Perspectives," Circular 779.

(GS 80)     U.S. Geological Survey, 1980, "Isolation of Uranium Mill
            TAilings and their Component Radionuclides from the Biosphere,
            by Edward Landa, Circular 814.

(JR 80)     JRB Associates, Inc., "Manual for Remedial Actions at Waste
            Disposal Sites," draft  final report under EPA Contract
            No. 68-01-4839, submitted June 1980.

(LU 78)     Lush et al., 1978, "An Assessment  of the Long-Term Interaction
            of UraniunTTailings with the Natural Environment," from
            Proceedings  of  the Seminars on Management, Stabilization and
            Environmental Impact of Uranium Mill Tailings, The OECD Nuclear
            Energy Agency,  pp. 373-398.

(MA 79)     Markos,  G.,  1979, "Geochemical Mobility and Transfer of
            Contaminants in Uranium Mill Tailings," from Proceedings of the
            Second Symposium on Uranium Mill Tailings Management, Colorado
            State Univ., Nov.  1979.
                                     5-17

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(NE 78)      Nelson,  J.D.,  Shepherd,  T.A.,  April 1978,  "Evaluation of
            Long-Term Stability  of Uranium Tailing Disposal  Alternatives,"
            Civil Engineering Department,  Colorado  State University,
            prepared for Argonne National  Laboratory.

(NR 79)     U.S. Nuclear Regulatory Commission, April  1979,  "Generic
            Environmental  Impact Statement on Uranium  Milling,"  NUREG-0511-

(RO 77)     Rochlin, G.I., "Long-term Waste Management:  Criteria or
            Standards?" in Proceedings of  a Workshop on Issues Pertinent to
            the Development of Environmental Protection Criteria for
            Radioactive Wastes,  EPA Report ORP/CSD-77-1 (1977).

(SC 74)     Schiager, K.J., July 1974, "Analysis of Radiation Exposures on
            or Near Uranium Mill Tailings  Piles," in Radiation Data and
            Reports, pp. 411-425.                                     ~~

(SC 77)     Schiager, K.J., "Radwaste Radium-Radon Risk," in Proceedings
            of  a Workshop on Policy and Technical Issues Pertinent  to the
            Development of Environmental Protection Criteria for
            Radioactive Wastes,  EPA Report ORP/CSD-77-2  (1977).

(SH 78)     Shreve,  J.D., Jr.,  July 1978,  in Proceedings of the  Seminar on
            Management, Stabilization and  Environmental  Impact  of Uranium
            Mill Tailings, the  OECD Nuclear Energy Agency,  p. 350.
                                      5-18

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           6:  MONETARY COSTS AND THE EFFECTS OF TAILINGS DISPOSAL








     This chapter presents  the  range of monetary costs  for alternative




pollutant control levels, and addresses the  longevity characteristics of




disposal methods, the potential environmental impact of controls,




occupational hazards, and effects of the disposal program on the economy.








6.1  Estimated Costs




     Cost estimates assume  an inactive tailings pile whose area, volume,




and weight approximate the  average values for piles at  21 inactive sites.




This "average" pile has a surface area of a  little more than 19 hectares




(190,000 square meters, or  47 acres), contains 780,000  cubic meters (1




million cubic yards) of tailings, and weighs 1.3 million short.tons.  The




pile is shaped like a truncated pyramid with a base approximately 440




meters (1440 feet) on a side, including the embankments.  The radon-222




release rate is assumed to be 450 pCi/m2-sec,  (More detail on the




"average" pile is given in  Appendix B.)  Cost estimates for a tailings pile




of different size can be scaled from the "average" pile by using the unit




costs developed for individual tasks and the purchase of specific items, as




presented in Appendix B.   (These items include earth work, liners and caps,




stabilizers, fencing, irrigation, matrix fixation, tailings transportation,




discount rate,  discounted value of future  costs,  and land  costs.)  The unit




costs are used  to estimate the costs of applying various control methods to




the "average" tailings pile.

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   The general control alternatives considered in this EIS are:








    (1) Leaving the uranium mill tailings where they are, but restricting




       access to the  site.  Particulate releases may be reduced by




       stabilizing the surfaces of the pile.




    (2) Covering the tailings pile to control radon-222 releases,



       particulate releases, gamma radiation,  and  water  contamination.




    (3) Transporting the  tailings  to a new  site,  placing  them in an



        excavated  pit  with a surface  impervious to moisture, and covering




        the tailings  to control radon  releases, particulate releases, and




        gamma radiation.



    (4) Transporting the tailings for deep disposal to a nearby open-pit




        or deep mine; or treating the tailings to  remove radium  (and




        possibly other substances, such as thorium).  This  option  provides




        long-term control of radon releases,  particulate releases,  and




        gamma radiation.



    Disposal costs depend on the  choice of option  for  general  control,  and



on the level of  control within  each option.  For simplicity, we have




computed  only the  highest and  lowest  costs  for each combination of a



general option and a specific radon control level.  Table 6-1 summarizes




these costs. (See Appendix B for the  details.)








      The costs shown  in Table 6-1 do not necessarily represent conditions




 at  any of  the actual  inactive sites, but they do cover all  possible option




 combinations.  For example, the  least expensive mehtod for  satisfying
                                      6-2

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                                                                                 TABLE 6-1
                                                   Ranges of Estimated Costs by Disposal  Option and  Radon Control Level

                                                       for the  "Average^  Tailings  Pile (in millions of 1978 dollars)
                Disposal  Option
450
                                                                   100
-Radon-222 Control Level

 10	    5
                                                                                                                                              . 1 and below
                1.   No control  except


                      Fencing                   $.8 to  1.4

                      Surface stabilization     $.5 to  3.6
I
CO
                2.  Cover to control  radon
                3.  Below grade
                                                              $ .6 to  4.3    $  .8  to   5.4    5 .9 to  5.8    $1.0 to  6.3    $1.0 to  7.0
          $5.4 to 11.2    $5.8 to 12.5    $5.8 to 12.8    $6.0 to 13.3    $5.7 to 13.9
                4.  Other

                      Radium concentration

                      Deep disposal
                                                                                          $69.2 to 75.7

                                                                                           $6.9 to 57.6
                 asphalt cap used

-------
control options 2 and 3 (for all radon control levels) assumes that



vegetation will be used for surface stabilization, and that neither




irrigation nor the purchase of a suitable top soil will be required.  The




most expensive surface stabilization method under control options  2 and




uses riprap, or  large stones.








    Radiological protection and measurements  costs associated with




 performing disposal  operations  are not included in Table  6-1  or




 Appendix B.   These cover  such operations as radiological  monitoring of



 workers, controlling pollutant releases while moving or grading a tailings




 pile,  surveying and  sampling contaminated soil, and  cleaning transporta-




 tion vehicles.  Estimating such costs is difficult because neither the




 length of time  that disposal operations will  require nor the radiological



 survey  and analysis procedures have been set.  Based on data provided by




 Smith and Lambert (SM 78), however, we estimate that operational



 radiological  procedures  will add  about  $150,000  (1978) to the disposal




 costs of the  "average" pile  for each  year disposal  operations are



 performed.








  6.2   Estimated  Health Benefits




      The benefits of any  disposal  option depend on how much  the option




  reduces potential harmful effects, and for how long.  The first option —




  control limited to fencing, or surface stabilization and a fence — would




  not reduce radon releases from the tailings  to the air or water




  contamination.  Controlling access to land near the pile would reduce
                                       6-4

-------
doses only to those few people who might otherwise live or work there.

Even this limited benefit would depend on institutional control and should

not be expected to last for more than a few centuries.



    Benefits under the second option — covering the tailings at the

existing site — would be directly proportional to the degree of reduction

in radon releases.  For example, reducing an uncontrolled radon release

rate of 450 pCi/m2-sec to 10 pCi/m2-sec would avert about 98% of the

potential effects of radon emitted from the uncontrolled pile.

Controlling radon releases to any significant degree would also prevent

release of particulates and reduce direct gamma radiation to negligible

levels.  Suitable covers will protect surface and ground water by limiting

precipitation infiltration.  Each site's characteristics would determine a

need for more specific water protection methods.



    The third option — moving  the tailings below grade, with a liner if

needed ~ would specifically control potential ground and surface water

hazards.



    The fourth option is either acid leaching to concentrate the

radium(l), which would then be disposed of using special procedures
     (DRemoval of additional radioactive materials, such as thorium and
uranium, could extend  the  period  over which radioactive hazards are
controlled  indefinitely.
                                      6-5

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(see Appendix B), or deep disposal of the mill tailings.  In principle,




this would provide the best prospect for long-term control of all the



options, but its praticality is the most uncertain.








     In describing these benefits, we assume the control methods will



perform as expected.  Table 6-2 summarizes the presumed benefits of the



various control options.








6.3  Longevity  of Control




     The  ultimate objective is to assure control  for as long as  the




material  is  potentially hazardous,  but we cannot  reasonably expect




instutional  control  to  last for more  than a  few hundred years.   Lasting




effectiveness  depends on  physical  disposal methods,  proper consideration of




site conditions,  and verification  of  disposal  performance over  the  short



term.   Beyond  the period  that  control may reasonably be expected to endure,




chance or natural events  becomes  the  determining  factor.








      Estimated control costs  depend more on the method than on the  degree




 of radon control.  The range  of  costs using different  methods  for a given




 radon control  level, in other words, is greater than the range of costs for




 different radon control levels.   The costliest methods generally would




 provide control for the longest periods of time.   Therefore, longevity may



 be the primary factor in determining the actual cost of control.
                                      6-6

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                                                                   TABLE 6-2
                                              General  Post-Disposal Benefits  of Disposal  Options
Disposal Option
                                                         Benefits of Control


CTt
-J

1. No control except fence
2. Cover existing surface site
to limit Radon Releases
to: 100 pCi/m'-sec
10 pCi/B2-sec
5 pCi/m2- sec
2 pCi/m2-sec
0.5 pCi/mz-sec
Radon Particulates
Minimal benefit Minimal benefit
78Z All
of health effects avoided Health Effects
avoided
97.81 avoided
98.9Z avoided
99. 6Z avoided
99. 9Z avoided
Gamma Radiation Surface/Ground Water
Minimal benefit No benefit
All Some ancillary control
Health Effects through limiting
avoided precipitation infiltration



 3.   New site,  below grade,
     with liner if needed
 4.  Deep disposal or
     acid leaching
Same as Option 2
     1001
of health effects
    avoided
Same as Option 2
Same as Option 2
Same as Option 2
Same as Option 2
Same as Option 2, plus
specific control of
potential ground and surface
water contamination
     as Option 3

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    Some disposal methods  should  last  much  longer  than others.   In




general, the thicker the cover, the longer  the control.  Thin covers of




artificial materials can greatly reduce radon releases but probably




wouldn't last very long.  Stabilizing a tailings pile's surface against




wind and water erosion is a key factor in control longevity for disposalat




or near the Earth's surface.   Stabilization requires  careful site




selection and durable surface  treatments.  Disposal in a suitable location




deep underground appears  to be a better way to  avoid  disruption of




tailings  by natural events or  people.








     Below-grade disposal  should be less subject to erosion than disposal




 above  grade.  Since all the  tailings  piles at inactive sites  are  now above




 grade, disposing of them below grade generally would mean choosing new




 locations.  This would present opportunities  for finding particularly




 suitable sites.  In practice, however, conditions specific to each site




 can blur these distinctions.  At some sites,  above-grade disposal




 techniques may offer stability  as good as that of below-grade  disposal.









     The  longevity  of any control method is difficult  to quantify.  Certain




 methods  should last  longer  than others, but  experience  with  all  control




 methods  is quite limited, especially considering  the time  that tailings




  will  remain hazardous.  We  would  expect above-grade disposal to  be




  effective for hundreds to  thousands  of years;  below-grade  disposal,




  thousands of years;  and deep disposal, tens  of thousands of years or
                                       6-8

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more.  Since longevity can only be described in broad terms, it is



impossible to relate the costs of specific long-lasting control methods



directly to estimates of the adverse health effects they will avoid.  The




goal, however is to isolate tailings for as long as may reasonably be




done, avoiding future harm at least for that period.








6.4  Environmental Impacts of Control^



    Cleanup, transportation, and final disposal of tailings will have an




adverse effect on the environment.  Excavating and hauling tailings, for



example, may increase airborne particulates, though attention to control




of dust will reduce the problem.  Radon-222 releases might also rise




temporarily as tailings are uncovered or  piled in a new physical




arrangement.  Surface runoff and other natural forces may increase



erosion.  Tailings  or other contaminated  materials will probably spill,




and  good housekeeping practices will be needed to assure they are cleaned




up and  not  spread around the environment.








     Cleanup of contaminated land will require hauling material  to a



disposal  site,  increasing  road  traffic,  dust, noise,  fumes,  and the




possibility of accidents.  Moving  tailings  to a new location will incur



 similar risks.   Disrupting vegetation at a new  site,  or  obtaining material




 to cover  the  tailings,  produces  an adverse  impact.
                                      6-9

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    All of these effects  will  be  temporary.   Compared  to the long-term.




impact of uncontrolled tailings,  these temporary effects, if reduced as




much as is practical, could be considered negligible.








6.5  Occupational Hazards




    The workers who  carry out the tailings controls will face hazards.




Workers who clean and move uranium tailings will be exposed  to more gamma




radiation and radioactive airborne particulates than most other workers  in




earth  moving occupations.  Normal health physics procedures to control




radiation and exposure will have to  be  employed  (HA Ip).  Hazards  from




 trucks and other earth-moving equipment will be  similar to  those  from any




 large-scale earth-moving project.  Any  occupational hazards will  be




 temporary, and can be considered negligible compared  to the long-term



 impact of uncontrolled tailings.








 6.6  Local Economic Considerations




     The  possibility of economic gains to communities near the tailings




 sites offsets  the temporary  adverse environmental impacts  and occupational




 hazards  to an  extent.  The cleanup  activities may provide  temporary jobs




 to unemployed  workers.  Local business  activity may increase.  The




 community may  gain  the  use of previously contaminated  land and




  structures.  The  disposal sites, however, will be licensed by the NRC,




 which may limit or  prohibit  their public use.   Since public funds spent to




  control tailings will be  unavailable for other  uses, local economic  gains




  may be  offset  by dampening  of other national economic  sectors.
                                      6-10

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                          References for Chapter 6

(HA Ip)  Hans,  J.M.,  Jr.  Burris,  E., Gorsuch,  T.,  "Radioactive Waste
         Management at the Former Shiprock Uranium Mill Site,"
         Environmental Protection Agency Technical Note (in preparation;.

(SM 78)  Smith, C. Bruce  and Lambert, Janet A., June 1978, "Technology and
         Costs  for Cleaning Up Land Contaminated with Plutonium,   in
         "Selected Topics:  Transuranium Elements in The General
         Environment," U.S. Environmental Protection Agency, ORP/CSD-78-1.
                                     6-11

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       7:   CONSIDERATIONS FOR CLEANUP OF CONTAMINATED LAND AND BUILDINGS

 7.1   Introduction
      Because land areas have been contaminated by wind- and water-borne
 tailings,  tailing diapoaal will include disposal of some contaminated
 soils.   If the control method chosen for disposal of a tailings pile
 requires moving it,  contaminated soil beneath the pile must also be
 disposed of.
      Buildings, too,  have contaminated, by tailings carried by wind and
 water  and  used as fill under and around the structures.   Buildings  once
 part  of  the mill  operation are  also  contaminated to various degrees.

 7-2  Off-Site  Contamination
     Sec.  3.1  discussed  a study to locate  tailings  in  communities near
 inactive processing sites.   Table 3-5 indicates  that of 22,213 radiation
 anomalies  (a gamma radiation level higher  than normal)  detected in  the
 regions surveyed  with  a mobile  gamma  radiation scanner,  6,518  of these  were
 traced to  uranium mill  tailings,  7,889  to  other  radioactive sources
 (including luminous dial  alarm  clocks and mined  uranium), and  955 to
 naturally  occurring radioactivity; 6,851 anomalies  were  of  unknown origin
 (OR 73).

     These data include Grand Junction, Colorado, where, because  tailings
were used on a large scale in construction, a Federal/State remedial action
program for affected buildings  is underway.  In Mesa County, where Grand
Junction is located, over 25,000 locations had been screened as of
October 15, 1978,

-------
to Identify possible tailings (GJ 79).  More than 6,000 locations had some



tailings on the property; the rest had none.  Of the locations with



tailings, about 800 are expected to receive remedial action, ?00 more




qualify for remedial action but the property owners probably will not



apply, and the approximately 5,000 remaining have radiation levels below



the program criteria for remedial action.   In Mesa County tailings also



were  used  to build  sewer and water lines, streets, nnd  other projects,



which will be  eligible  for remedial actions under PL 95-604.








      Gamma radiation  surveys  established  the  extent of contamination near



 the  inactive  processing sites  from wind and water  erosion  of  tailings piles



 (Table  3-6).   More than 5,000  acres  had gamma radiation above the normal



 background had gamma  radiation above the normal background level.  The area



 with gamma radiation  levels equal to or greater than  10 uR/hr above



 background is more than 2,000 acres.  This figure omits the surface areas



 of the tailings piles themselves, about 1,000 acres.








      The seriousness of off-site contamination depends on the degree of



 contamination and  the potential exposure to people.  The amount  of  land  and




 number of buildings that will require  cleanup will be  determined by the



 cleanup standards  selected.








 7.3  Potential Hazards  of Off-site  Contamination



      The  greatest  hazard posed  by tailings on  open lands  is  their  potential




  to  increase  levels of radon  decay products in  buildings.   Exposure  to
                                       7-2

-------
direct gamma radiation and contamination of drinking water and food may




also occur, but generally will be of less concern.








     There is a health risk associated with radon decay products.  Their



concentration in an existing or future building will depend on the radium



concentration in the soil under or adjacent to it.  So many other factors



affect the indoor radon decay product concentration, however, that



establishing a useful correlation with the radium in soil is difficult.



Nevertheless, Healy and Rogers  (HE 78) have anaylzed exposure pathways due



to radium  in soils, whether occurring naturally or as contamination.  They



argue  that one might  expect indoor  radon  decay product  concentrations of



0.01  WL  for  soils with  radium concentrations  of  1 to 3  pCi/gm to a depth  of



one meter  or more.  NRC estimates  (NR 79)  that 3  to 5 pCi/gm  of  radium can



cause indoor concentrations of  0.01  WL.   Both of  these  calculations  are



approximations,  but radium  concentrations near  the  lower end  of  these




ranges correspond  to  common natural  soil  conditions.   Therefore, where



indoor radon decay product  concentrations are only  slightly elevated,



tailings may not be the dominant  cause,  so remedial action for  tailings  may



have  little beneficial effect.   Moreover, cleaning contaminated  open land



will  not eliminate elevated radon decay product  levels in future buildings,




 though it generally will reduce the frequency with which they occur.








      Tailings also emit gamma radiation, which can penetrate the body from



 the outside.  We expect that the indoor radon decay product concentration




 standards generally will be met by removing  tailings from the building, and
                                      7-3

-------
this will eliminate any indoor gamma radiation problem.  For some



buildings, however, removing the tailings completely may be impractical



(more for engineering reasons than for cost).  Alternatives, such as air




cleaning, improving ventilation, or applying sealants to the walls and



floors, are available.  If these are used, standards will be needed to



limit gamma radiation exposure of the occupants.








     Natural or contaminated  soils with radium concentrations of  5 pCi/gm



through  a depth of several feet  can have  gamma radiation exposure rates  of




about 80  mR/yr (NC 76).   Exposure rates are proportionately higher or  lower



for other radium  concentrations, and  decrease as  the  layer  of



radium-containing material becomes  thinner or is  covered over by  other



materials.   The potential for causing elevated  indoor radon decay product



 levels  in future  buildings on such  soils  also depends on  these  factors.



 Therefore,  cleanup standards for open land should consider both the radium




 concentration and the thickness of  the contaminated soil.








      Each gram of natural uranium contains 330,000 pCi of U-238 and 15,000



 pCi of U-235.  Because it appears in relatively small proportion, U-235 and



 its radioactive  decay products usually may be ignored in evaluating the



 hazard of uranium tailings.  The dominant hazard from most tailings is from



 decay products of U-238, including radium-226 and  its decay products.



 Other radioactive substances in the tailing will ordinary pose much less



 risk to  health than  that from radium-226.
                                       7-4

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     The total protection that a standard based on radium-226 provides



depends on the extent to which radium has been separated from other



radioactive substances, such as thorium and the U-235 decay products,



during ore processing.  If significant separation occurs, radium-226



concentration in the residual material may not adequately measure the



radiation hazard.  For example, thorium separates from radium in uranium



mills using the acid leach process.  Although thorlum-230 and radium-226



occur in ore in about equal amounts of radioactivity, thorium compounds are



more soluble in acid.  Therefore, thorium radioactivity concentrations in




the wastewater may be thousands of times higher than for radium, and more



thorium may then seep through the pile to the soil below (RA ?8).  However,




chemical interaction of thorium with the soils should retard further




movement (GS 80).







     At least one of the processing sites covered under  Public Law 95-604




(Canonsburg, Pa.) may have tailings containing higher than usual



Proportions of U-235 decay products.  Although little is known about the



environmental pathways and biological effects of  these radionuclides,



site-specific information on  their concentrations suggest  that they are



unlikely to be a determining  factor in cleanup decisions (DO 78).  The




U-238 decay products are present  in greater amounts.








7.4  Remedial Actions  and Costs



     The only remedial action  that would eliminate the hazards from



contaminated  land and  buildings would be to remove uranium mill  tailings
                                      7-5

-------
from under and  around buildings and  from open land,  and to dispose of them
along with the  tailings pile.   The cost and complexity of removing tailing3
from buildings  depends on the  amount of tailings and their location
relative to the structure.  Tailings used as backfill around the outside of
a foundation, for example can  be removed easily at relatively low cost.
Removing tailings from under a floor or foundation, on the other hand,
entails breaking up concrete to reach  the tailings, a costlier and more
complex procedure.  In 1972, Congress  enacted PL 92-314, authorizing
remedial  action  for  buildings  in Grand  Junction, Colorado, affected by  that
community's  extensive use of tailings  in construction.   Experience gained
through seven  years  of  that program illustrates  the  remedial action costs
that  may  be  incurred  for similar  situations  in  other  places under  PL
95-604.   In  the  Grand  Junction remedial action  program,  the average cost to
treat a residential  structure  has been about $13,500, ranging  from $540 to
$41,000  
-------
7.5  Previous Standards for Indoor Radon Decay Product Concentration



     Government agencies of the United States and Canada have previously



published remedial action criteria for radon decay product concentrations




in buildings.







     The U.S. Surgeon General's 1970 remedial action guidance for Grand




Junction, Colorado, applies to buildings on or containing uranium mill



tailings (PE 70).  EPA's guidance to the State of Florida applies to



buildings on radium-bearing phosphate lands (FR 4H).  Each set of guides



has two levels:  1) Radon decay product concentrations above the upper



level require action; 2) those below the lower level do not; 3) between




these levels, local factors determine the action required.








     The Surgeon General's Guides are implemented in the Department of



Energy's regulations for remedial action at Grand Junction, Colorado (10




CFR 712).  In effect, they adopt the lower level as an action level for



schools and residences, and the midpoint between the lower and upper levels



as an action level for other buildings.  This difference in action levels



recognizes that children should have added protection, and that people



occupy residences and commercial building for different periods.  For radon



decay product concentrations these actions levels are 0.01 WL and 0.03 WL,



respectively, above background.  The average background indoor radon decay



Product concentration determined for use in the Grand Junction remedial




action program is 0.007 WL.
                                     7-7

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     The Canadian cleanup criteria (AE 77)  and the EPA recommendations for
residences on phosphate lands in Florida require remedial action for indoor
radon decay product concentrations greater than 0.02 WL (including
background).  The EPA guidance further recommends that concentrations below
0.02 WL be reduced further recommends that concentrations below 0.02 WL be
reduced as low as can be reasonably achieved.  Reductions below 0.005 WL
above the average normal background (for nearby lands in Florida) of O.OOU
WL are not generally justifiable in the Florida phosphate lands.  For
Florida, then, EPA has in effect recommended remedial action above 0.2 WL:
stated that  action is generally unjustified at concentrations  less than
0.009 WL; and left action at  intermediate  levels  to the judgment of local
officials.

      Surveys have been  conducted  to  find buildings which may  be affected  by
tailing  for which remedial  actions may be  conducted under  PL  95-60M.   These
surveys show a  variety of affected structures, whose  elevated radiation
levels  have several  different causes.   The total  number  of buildings  that
will be eligible under PL 95-604  is  not fully established,  but we believe
they are fewer  or comparable in number to  those  in Grand Junction,  that  is,
 several hundred.

 7'6  Normal Indoor Radon Decay Product Concentrations
      The indoor radon decay product concentration of a building affected by
 tailings is the sum of contributions from tailings and from the natural
 environment.  These contributions cannot be distinguished from one
                                      7-8

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another.  Knowledge of the characteristics of radon decay product
concentrations in normal buildings is very useful in eciding the best form
for a remedial action standard and in choosing a practical action level.

     The most complete studies of normal indoor radon decay product
concentrations in the United States were performed on buildings in Grand
Junction, Colorado (PE 77), New Jersey and New York (GE 78), and Florida
(FL 78).  The samples and measurement techniques of these studies are not
exactly comparable, however.  The New Jersey-New York buildings studied
were residences, mostly single-family one-or two-story buildings.  The
Grand Junction sample was mainly houses, about half of which had basements
(CO 79).  The reported Grand Junction data are for the lowest "habitable
portion" of the building.  The Florida sample is single-family houses
without basements.

     Some results from these studies are summarized in Table 7-1.  In all
cases, the reported concentrations are the average of measurements taken
over a year.  The data indicate wide variations in normal indoor radon
decay product concentrations within each sample, even for a relatively
uniform sample of buildings.  Furthermore, the New Jersey-New York data
show that concentrations at ground level are about half of those in the
basement.  (An unpublished analysis of the G-and Junction data shows a
similar effect (CO 79).)

     Many buildings in the western United States, where most of the sites
covered under PL 95-604 are located, have basements.  For
                                     7-9

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                                  TABLE 7-1

              Average Annual Radon Decay Product Concentrations
                             in Normal Buildings
Grand Junction. Colorado (a)

     Sample:  29 buildings, mostly houses, about half with basements.
     Range:           0.002-0.017 WL
     Median:          0.007 WL
     Above 0.01 WL:   30?
     Above 0.015 WL:  10% (approx.)



New Jersey-New York(b)

     Sample:  21 houses, mostly single-family with full basements.
                          Cellar                       First Floor
     Range:           0.0017 - 0.027 WL                -
        0.0017 - 0.013 WL
     Median:          0.008 WL                      0.004 WL
     Above 0.01 WL:   14056                           8$
     Above 0.015 WL:  20J6
 Florida(c)


      Sample:   28  single-family residences, without  basements.
      Range:           0.001 - 0.012 WL
      Median:          0.0035 WL
      'bove 0.01 WL:   3?
      Above 0.015  WL:  0%
 (a)References (PE 77)  and  (CO  79).

 (b)Reference (GE 78).

 (c)Reference (FL 78).
                                     7-10

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these buildings in particular, the most important conclusions we draw from
these studies are the following:

     1.  Normal indoor radon decay product concentrations vary greatly.
     2.  Concentrations greater than 0.01 WL in a useable part of a normal
building are commonplace.
     3.  Though less common, normal concentrations greater than 0.015 WL
are not rare.

7.7 Practicality of Alternative Remedial Action Standards for Buildings
     Experience in the Grand Junction program aids in estimating the scope
of a cleanup program for tailings under alternative remedial action
criteria.  Table 7-2 gives the Grand Junction program's results (CO 79)
for buildings having tailings for which radon decay product measurements
have been made.  For residences and schools, the remedial action level is
0.01 WL above background.  Among the 463 residences and schools sampled,
217 were eligible for remedial action.  If the action level had been 0.005
WL rather than 0.01 WL the number eligible would have risen to 278, a 28$.

     Table 7-2 also shows that 60 residences and schools have been treated
but not yet brought below the action level.  Had the action level been
0.005 instead of 0.01 WL above background, 111 rather than 60 would need
further remedial work.
                                     7-11

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                                TABLE 7-2
            Experience with Grand Junction Remedial Action Program
                         Total

  Non-eligible

Residences and Schools    246

Other                      76
   Number Above
0.01V7L + Background
                                              0

                                             10
                                                              Number Between
                                                            0.005WL and 0.01WL
                                                             Above
                              61

                               12
  Post-remedial

Residences and Schools    217

Other                      35
         60(c)

         17
                                                                     51

                                                                      9
 (a)Modified from reference (CO 79).

 (b)Table entries are numbers of buildings having  tailings  for  which
    radon decay  product measurements  have been made.

 (c)Buildings  for which  remedial actions  have not  been  completed.
                                      7-12

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     Table 7-2 ."hows that 40 or 52 additional buildings other than



residences and schools would have been eligible if the action level for



them had been 0.01 WL or 0.005 WL above background, respectively, rather




than the 0.03 prescribed.  This is an increase of  lUt or 149*,



respectively, in the program for that category of buildings.  The table



also shows that at the'lower action levels additional work would be needed



for 1? to 26 of the buildings other than residences and schools on which




remedial action has already been performed.
                                     7-13

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                          References for Chapter 7

(AE 77)   Atomic Energy Control  Board  of Canada,  "Criteria  for Radioactive
         Cleanup in Canada,"  Information Bulletin  77-2,  April 7,  1977.

(CO 79)   Colorado Department  of Health,  October  3,  1979, Letter from A.
         Harold Langner,  Jr., and  subsequent  conversations.

(DO 78)   Department of Energy,  Report No.  DOE/EV-0005/3, April 1978.

(PB 76-78)     Ford, Bacon,  and  Davis, Utah,  Inc.,  "Phase II-Title 1,
              Engineering Assessment  of Inactive Uranium Mill Tailings," 20
                    f H?°rtS  for Department of Energy  Contract No.
                  -1)-1658,  1976-1978.
(FB 79)  Ford,  Bacon,  and Davis,  Utah,  Inc.,  July 1979,  "Engineering
         Evaluation of the Former Vitro Rare  Metal Plant,  Canonsburg,
         Pennsylvania" and "Engineering Evaluation of the  Pennsylvania
         Railroad Landfill Site,  Burrell Township, Pennsylvania."

(FL 78)  Florida Department of Health  and Rehabilitative Services,  "Study
         of Radon Daughter Concentrations in  Structures  in Polk and
         Hillsborough Counties,"  January 1978.

(FR 4!4)  Federal Register HHr  p 38664-38670,  July 2,  1979.
            onn       n        '  A'J"  "The Distribution of Ambient
         Radon and Radon Daughters in Residential Buildings in ^he New
         StlonYT;: ArY PreS6ntefi  at the Symposia8 o'the Natural
         Radiation in the Environment III, Houston,  Texas, April 1978.

(GJ 79)  Grand Junction Office, February 1979, "Progress Report on the
         Grand Junction Uranium Mill Taiiings Femedial ^^ p       „
         U.S. Department of Energy Report  DOE/EV-0033.

(GS 80)  U.S. Geological Survey, 1980, "Isolation of Uranium Mill Tailings
                                                the  ^sphere," by" Edward
(HE 78)  Healy, J.W., and Rodgers, J.C., October 1978,
                                Solls-"
(NC 76)  National Council on Radiation Protection and Measurements
         December 1976, "Environmental Radiation Measurements," NCRP Report
         No. 50.
                                     7-1U

-------
(NR 79)  U.S. Nuclear Regulatory Commission, April 1979,  "Generic
         Environmental Impact Statement on Uranium Milling," Volume II,
         App. J, NUREG-0511.

(OR 73)  Office of Radiation Programs,  March 1973, "Summary Report of the
         Radiation Surveys Performed in Selected Communities,"  U.S.
         Environmental Protection Agency.

(PE 70)  Letter by Pau J.  Peterson,  Acting Surgeon General  to Dr.  R.L.
         Cleere, Executive Director, Colorado State Department  of Health,
         July 1970.

(PE 77)  Peterson, Bruce H., "Background Working Levels and the Remedial
         Action Guidelines," in the  Proceedings of a Radon  Workshop,
         Department of Energy Report No. HASL-325, July 1977.

    78)  Rahn,  P.H., and Mabes, D.L.,  "Seepage from Uranium Tailings  Ponds
         and its Impact on Ground Water,"  Proceedings of  the Seminar  on
         Management, Stabilization,  and Environmental Impact of Uranium
         Mill Tailings, July 1978,  the  OECD Nuclear Energy  Agency.
                                    7-1?

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                     8:   SELECTING THE PROPOSED STANDARDS

     In PL 95-604, the Congress stated its findings that tailings "may pose
a potential and significant radiation health hazard to the public" and that
"every reasonable effort should be made to provide for stabilization,
disposal, and control in a safe and environmentally sound manner of such
tailings in order to prevent or minimize radon diffusion into the environ-
ment and to prevent or minimize other environmental hazards from such
tailings."  The Environmental Protection Agency was directed by Congress to
set "standards of general application for the protection of the public
health, safety, and the environment" for such materials.  The legislative
record also shows that Congress intended that these standards apply to all
sites rather than be site-specific.

     The Committee report on the Uranium Mill Tailings Radiation Control
Act expressed the intent that the technologies used for remedial actions
should be effective for more than a short period of time:  "The Committee
does not want to visit this problem again with additional aid.  The remedial
action must be done right the first time" (House of Representatives  Report
95-1480, Part 2).

     Our proposed standards (Appendix D)  are  meant to  ensure  a long-lasting
solution.
     Disposal Standards
     Our analysis  of the health effects from tailings  piles  shows  that they
   mainly caused  by radon emissions  into the air.   Environmental

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contamination also can occur if toxic chemicals from tailings enter surface
or underground water,  though this depends strongly on individual site
characteristics.

8.1.1.  Radon Standard
     From our analysis of health effects of tailings piles, we conclude
that:


     a. Lung cancer caused by radon's short-lived decay products is the
dominant radiation hazard from untreated uranium mill tailings piles on
local, regional,  and national scales.  Effects of long-lived radon decay
products, of windblown tailings, and of direct gamma radiation from the
piles are much less significant.


     b. Individuals near a pile bear much higher radiation risks than those
far  away.  We  estimate,  for example, that individuals continuously living
one  mile from  a large pile wouid have about 20Q times gg ^^ & ^^ Q£
a  fatal lung cancer (7 in 10,000 versus 3 in  1,000,000) caused by radon
products from  the pile as would individuals living 20 miles away
(Table 4-2).   At  some of the piles, where people  live even closer than one
mile, the increased risk of developing  lung cancer over a lifetime is as
high as 4 chances  in  100 (Table 4-3).


      c. The  total number of cancer deaths that a  pile would  induce depends
strongly on  the  size  and locations of the  local  populations.
                                      8-2

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      d.  Based on recent population data,  all the 22 piles at inactive sites




 we  studied  taken together may  cause 40  to 90 deaths from lung  cancer  per



 century  among persons  living 50 miles or  more away from a pile.   When local




 and regional  rates are  added to  these,  the estimated total national effect




 of  all the  22 piles  is  about 200 premature deaths from lung  cancer  per




 century, or an annual rate of  about  two deaths.








      Part of  the uncertainty in  these estimates  results  from necessary




 approximations in estimating the environmental radiation  levels a tailings



 Pile  produces, and the  doses people will  receive.   Additional  uncertainty




 comes from our incomplete knowledge  of  the effects  on people of these




 generally low exposures.








     Our estimates are based upon current population sizes and geographical




 distributions.   Overall  increases in national population  would raise  the




 estimated national effects in  approximate proportion.  Development of new



 Population centers near  currently remote  piles,  and substantial growth of




 cities already near one, would increase these estimates proportionately.








     Unless radon emissions  from the  tailings piles covered under Title I




 of PL 95-604 are greatly reduced, they might prematurely kill about 200



 People per century into  the indefinite future.  Even for  piles remote  from




Population centers,  equity for people living nearby and the possibility of



 future development near  the sites argue for control measures.  A reasonable




effort to prevent or minimize radon emissions from piles is required under




PL 95-604.
                                     8-3

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     Methods for controlling radon emissions from piles are available.  The




most straightforward methods call for burying the piles or covering them



with appropriate combinations and thicknesses of soils, and with erosion-




resistant surfaces.  We believe the basic capabilities of these methods to



control radon releases, although largely untested, are understood.  Other




methods may also be useful  (Chapter 5, Appendix B, NRC's GEIS for Uranium




Milling (NR 79)).








      From several  perspectives,  as  discussed below, we find it  reasonable




 to reduce radon emission rates  from tailing at  inactive  processing sites




 from current values of several  hundred  pCi/m2-sec  to  a range more



 characteristic of ordinary land.  Typical natural emission rates are from




 0.5 to 1  pCi/m2-sec, with variations up to several times these values not



 unusual  (NR 79).








      Next, the form and numerical values of the standard must be fixed.




 Three quantities will be considered as alternative basic units  for the




 standard:  the radon release rate per unit area (expressed in pCi/m2-sec),



 the  total radon release  rate (pCi/sec, or Ci/yr), and the dose  or exposure




 of actual or hypothetical  individuals  or  populations  (mrem/yr,  person-



 rem/yr,  person-WLM,  etc.).








       We  rejected  a dose or exposure standard.   It is cumbersome to



  implement, with no compensating advantages except that  it relates directly




  to risk.  One major purpose of the standard is to guide the  design of



  disposal systems.  A dose or exposure standard would introduce uncertainty






                                       8-4

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into this process, because radon release rates must be known before dose or

exposure can be estimated.


     We also rejected a standard based on the total radon release rate.

Limiting the total radon release rate fails to take account of the great

differences in radioactivity among the piles (see Table 3-1).   A single

limit on total radon release from all piles could place unreasonable burdens

on the disposal designs.  A limit on release rate per unit area,  however,

may readily be applied uniformly to all sites.  Release rate per unit area

is also the most meaningful quantity for comparing the emission of a site

with that of normal land.  Since radon release rates change with the

climate, however, the standard should address the average rate over a

year's time.


     After considering the alternatives (see below) we have concluded

that the numerical limit on pile emissions, following disposal, should be

from about 0.5 to 2.0 pCi/m2-sec.  When added to the radon released from

a normal earth covering, the disposal site emission rate would still be

within a normal range.(1)  The risk for people living or working away

from the disposal site is a minor factor in choosing a standard within this

range,  since 98% or more of their exposure to radon comes from other

sources (NR 79).
          covering of average soil will contribute an additional 0.5 to
    pCi/m2-8ec.

                                     8-5

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     Disposal sites generally will be large enough for small communities to

be built upon.  It appears unlikely that a combination of emission,

residency, and construction factors would materialize that would create a

public health problem under a standard in the radon emission range we are

considering.  The incremental risk associated with the choice of a control

level within this range appears small enough so that other factors should

also be considered.




     Figure 5-1 shows that to control radon emissions by covering piles with

soil, the required covering thickness rises sharply(l) near a rate of

about 1 pCi/m2-8ec.  These curves  are based on theory and laboratory

tests;  there  has  been no  opportunity  to test  them against full-scale  field

experience.   If soil coverings should be  less efficient  in controlling

radon than  the curves  indicate,  meeting a standard at the low end of  the

radon emission range could be much more difficult and expensive  than  we

estimate.  The gain in health benefit,  moreover,  would be marginal.   We

 therefore propose to allow a tailings release rate of 2 pCi/m2-sec rather

 than a slightly lower  figure, to allow for more technical  flexibility in

 implementing the standard.




      We considered setting a higher or lower radon release  standard.

 Higher levels, from 10 to 40 pCi/m2-sec, perhaps, appear unjustified;

 such emission rates can be lowered to 2 pCi/m2-8ec for about 10 percent
      (l)Reducing emission from 10 to 9 pCi/m2-sec (a 10% reduction)
 requires about 1cm of added soil; the same size emission reduction from 2
 to 1 pCi/m2-Sec takes about 50 cm of added soil.
                                      8-6

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additional cost.(l)  With such elevated radon emissions, the probable

need for land-use restrictions adjacent to the disposal site would place a

continuing administrative burden on future generations.



     We also find near total control of radon release from the tailings

unjustified.  Incremental costs for achieving emission rates lower than

2 pCi/m2-sec rise faster than emissions drop, and any achievable health

benefits would be extremely expensive.  Restricting land use near the

disposal site because of radon releases from the tailings is unneeded for

radon emission levels near 2 pCi/n»2-sec.   We have found no administrative

or esthetic advantages in further reductions.(2)



     The proposed standard typically would reduce radon emissions and their

possible effects by 99%.  Measures that will cut down radon emissions this

much for at least one thousand years (see Section 8.1.5) will also eliminate

blown tailings and excess gamma radiation.  Therefore, implementing the
     (DThis assumes that covering the tailings with soils and clay is a
feasible method for radon control to an emission level of about
2 pCi/m2-8ec.  Tailings piles vary widely in their size and radioactivity
content.  Therefore, costs of applying the burial method or any other ade-
quate disposal technique will vary greatly among the piles.  We estimated
Potential disposal costs for a variety of methods (see Chapter 6 and
Appendix B).  For example, assuming the tailings would be taken to a new
site and buried in a shallow pit, we estimated the disposal cost for an
average pile as 6-13 million dollars (1978).  Costs for some piles may be
Partially offset by the value of residual uranium that may be recovered by
reprocessing the tailings before disposing of them,  or the reclamation
value of the original tailings site.

     (2)However, PL 95-604 provides that after remedial actions are
completed, the tailings will be in Federal custody under license by the
Nuclear Regulatory Commission.
                                     8-7

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radon control standard will virtually eliminate all the potential hazards




except water pollution.








8.1.2  Ground Water Standard



     Since most of the inactive sites are in dry climates, much of the water



that may ever infiltrate them has probably already done so during active




operation of the mill.  This probably is not true for all sites, and




standards  for protecting ground water after disposal of the  tailings  are




needed.








      Under the  proposed ground water standards (Appendix  D), after  a




 tailings pile is disposed  of,  it  may not cause the concentrations of




 certain pollutants in an underground source of drinking water to either




 (1) exceed the contaminant level specified for that pollutant, or




 (2) increase, where the background concentration of the pollutant already




 exceeds the applicable specified contaminant  level.  An underground  source




 of  drinking water is defined as an aquifer currently supplying drinking



 water for  human consumption, or an  aquifer in which the  concentration  of




 total dissolved solids is  less than 10,000 milligrams per liter (FR  79).








       The  proposed ground  water protection standards could be considered too




  strict if implementing them would be unreasonably  costly or if they  would



  be impossible to apply.   Information available suggests  that our proposals




  are practical.  The following sections discuss alternative  approaches to




  setting the standard, and describe the reasons for choosing the proposed



  standards.
                                       8-8

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Approach to Ground Water Protection


     These standards are conditions for disposal of uranium mill tailings


from inactive processing sites, not ambient water quality criteria.  We have


concluded that disposal of tailings should not degrade ground water beyond


levels that retain its fitness for direct consumption by people.  We recog-


nize that ground water quality is also important for other reasons? its


effect on fragile ecosystems, for example, and irrigation.  Other standards


may be appropriate to protect its usefulness for these other purposes.  We


believe, however, that the prevention of adverse human health effects from


direct consumption of ground water should be foremost among several


objectives in protecting ground water quality.





Contaminants of Concern

     Contaminant levels in the National Interim Primary Drinking Water Regu-


lations (NIPDWR) provide the best current guidance of adequate protection


levels for drinking water.  However, we also considered whether the NIPDWR


cover all contaminants found in tailings, or contaminants that are not.




     Except for fluorides, all the inorganic chemicals listed in the NIPDWR


nave been reported as present in tailings.(1)  However, uranium mill


tailings are not significant sources of organic chemicals, microbiological


contamination, or man-made radioactivity, so these categories of the NIPDWR


can be disregarded.
      --A«eBe !««»»..»* chemicals are «8«™c»
      mercury, nitrate, selenium, and silver.
      it to radioactivity limits in the NIPDWR.
                                     8-9

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     Other substances possibly harmful  to human health were not included in



the NIPDWR due to their relative rarity in drinking water systems, the lack




of analytical methods, the high costs of monitoring,  or the lack of toxicity




data.  Several such substances are present in leachate from tailings.  We




have reviewed these substances (see  Sections  4.8.2  and 4.8.3)  and have



included two — molybdenum and uranium ~ in our proposed standards, because




of the seriousness of their toxic effects on humans,  animals,  or plants,



their abundance in the tailings, and their expected environmental mobility-








     We have also considered the contaminants addressed by the National



Secondary Drinking Water Regulations (NSDWR).  The NSDWR (40 CFR 143)




represent EPA's best judgment of the standards necessary to protect




underground drinking water supplies from adverse odor, taste, color, and




other esthetic changes that would make  the water unfit for human consump-



tion.  We decided, however, not to include the contaminants identified in




the NSDWR in the proposed standards.  The list of contaminants we are



including covers the most hazardous substances in many different chemical




forms.  Conditions that control these toxic substances will also control




many other substances.U)  Me expect scientific analyses and predictions




based upon them to be the primary means of demonstrating compliance with


                                     8-10

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the standard, and do not wish to complicate that task by including
nonessential requirements.

     We also considered for coverage in these standards the pollutants
covered in the publication "Quality Criteria for Water" (EP 76).  "Quality
Criteria for Water" recommends levels for water quality according to the
objectives of Section 101(a) and the requirements of Section 304(a) of the
Clean Water Act.  Its primary purpose is to recommend levels for surface
water quality that will provide for the protection and propagation of fish
and other aquatic life, and for recreation.  While several health-related
substances that could be present in tailings leachate are listed, the
recommended limits are geared to protecting aquatic life and are not
appropriate for ground water.  Further, the recommended limits are written
as guidance in developing standards and not as standards themselves.
Therefore, we decided that this list was inappropriate for these standards.
 	of Contamination
     The proposed standards require a reasonable expectation that releases
from tailings piles will not cause:

     (a)  The concentrations of certain contaminants in ground water to
exceed specified levels, or

     (b)  An increase in the concentration of any of those contaminants in
ground water where the existing (upstream) concentration exceeds the
specified level.

                                     8-11

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     The first requirement, (a), protects water that can be used as




drinking water without treatment under current regulations, except that we



have added coverage of molybdenum and uranium.  The proposed concentration




level for molybdenum is appropriate for avoiding toxic effects in humans,



in accordance with the recommendations of a recent report to EPA (CH 79)•




The proposed standard for uranium is the level for which our estimate of




bone cancer risk is about  the same as the estimated bone cancer risk for




radium under the NIPDWR.  The second part, (b), protects ground water



already  at or above the maximum contaminant level, by preventing increases




in contaminant concentrations.








     We  considered several arguments  for more  lenient standards than those




proposed:   (a) The increased  disposal cost might  be  greater than  the value




of  the  threatened resource;  (b) treating  the water after contamination




would be a more  efficient way to remove undesirable  substances;  and




 (c)  some of  the  allowable levels  are  commonly  exceeded  in  ambient  or native




 ground  water,  effectively resulting in a nondegradation standard for those



 aquifers.








     We respond  to  these arguments as follows:




      (a)  We are not required to balance disposal costs against the value




 of ground water  resources, nor can the "value" be determined for an



 indefinite future.   Moreover, we do not know and probably cannot determine




 a useable relationship between disposal costs and specific ground water




 protection requirements.  We believe the proposed standards are a



 reasonable approach to ground water protection.






                                      8-12

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     (b)  Treating ground water after contamination may be efficient when




it is done, but undoubtedly some people will continue to use untreated



water.  We believe it preferable, and more consistent with the intentions




of Congress, to minimize the need to treat water.  Tailings piles disposed



of in accordance with the proposed standard should not cause ground water




"problems" for people in the future.  We cannot be as sure that more




lenient standards will provide adequate protection.








     (c)  We expect that our standards often will amount to nondegradation




standards, because native levels of dissolved substances in aquifers where




the piles are located are often not very low.  We have no compelling reasons




to allow tailings to increase these levels, however.  If the native water




quality itself may present problems for future users of increasingly scarce




ground water resources, why should disposal of these tailings piles be




allowed to worsen the situation?








     Reasons we considered for adopting more stringent standards include:




(a) tailings disposal is only one of several sources of ground water con-




tamination, and each source contributes to the overall rise in contaminant



levels; (b) future research may find that lower  levels are necessary to




adequately protect health; (c) some agricultural, industrial and other



important uses of ground water may be impaired;  and (d) ground water is




often consumed without treatment, so more stringent standards would require




less reliance on monitoring and treatment before domestic usage.
                                     8-13

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     Our analysis of these reasons follows:
     (a)  The proposed standard does  recognize that an aquifer may be
polluted by several sources.  Where existing ground water contaminant
concentrations exceed the levels specified in the  proposed standards, the
disposal system should be designed not to allow contaminant levels to
increase at all.   Future sources of contamination,  when added to releases
from tailings, may cause increases in earlier concentration levels.  If the
resulting increases are large, however,  under the  standards contaminants
from the tailings will not be the dominant contributors to the increases.
Releases from the tailings, when added to contaminants from other sources,
could be the major factor in causing small increases in concentrations, but
small increases are not very significant.


     (b)  Since tailings are mainly the ground up residues of rock,
contaminants that may leach from them into water are already present in
varying degrees in native ground and surface waters.  People have always
consumed water containing these substances,  so it  appears unlikely that
these substances will be found in the future to be very much more toxic
than we presently believe.   Further,  our standards  apply only to the
relatively few sites covered by the Title I program Of PL 95-604.  Under
the circumstances, any harm that might be avoided  by stricter standards is
both small and speculative.


     CO  Our proposed standards would allow very  good quality water to be
slightly degraded.  If and when this occurs some uses of the water might be
-Paired.  Such impairments are speculative.  In view of the limited number
                                    8-14

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°f sites to which the standards apply and the degree of protection they




afford  for  good  quality  water,  the  possibility of such impairments does not




appear  to be a serious defect in the proposals.








     (d) Our standards  are  designed to protect people who may directly con-



sume the water.   Whatever the standards may be, the purpose of monitoring is




to determine actual  contaminant levels.  The extent of necessary monitoring




at any  site should be determined in part by considering the possibility of




unexpected  failures  of the disposal system and other site-specific factors.




lt seems doubtful that stricter standards would have much influence on such
      the Standard is Applied



     Another issue regarding ground water protection is the physical point




at which the standard should be applied.  At what point in the aquifer, in




other words, does contamination from tailings constitute noncompliance?




1116 Places we considered are the site boundary, the waste boundary, or some




8Pecifie
-------
     Applying the standard to the waste boundary would minimize the affected
area.  However, the tailings at inactive processing sites have, to some
extent, merged with their immediate surroundings, so the waste boundary may
be hard to define.  More significantly, a standard applied so near the waste
may be difficult to meet at some otherwise adequate existing sites.  Where
the standards might be exceeded only in the immediate neighborhood of a
pile, the cost of liners and re-siting to avoid the violation appears to be
unjustified.  To avoid these higher costs and their small benefits, a strict
standard should apply only beyond some distance.  We propose this distance
to be 1.0 kilometer from the smallest practical boundary of the waste when
an existing tailings site is used for disposal.  A smaller distance of
application might not serve our intended purpose of avoiding large expedi-
tures for very little gain, and we believe that a much larger distance would
be insufficiently protective.  However, if tailings are moved to a new
disposal site, for whatever reason, then new opportunities for site selec-
tion and preparation become available.  For new sites we propose to apply
the standards 0.1 kilometer from the waste boundary.  In effect, this is as
protective as applying it at the waste boundary, while allowing some
benefit from sorption and dilution in immediately adjacent ground, in case
small leaks occur.
            Drinking Water Source
     The choice of the 10,000 mg/1 total dissolved solids measure for
usable aquifers follows EPA's general policy that ground water resources
below that concentration be protected for possible use as drinking water
sources.  This policy is based on the Safe Drinking Water Act and its
                                     8-16

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legislative history, which reflects Congressional intent that aquifers in

that class deserve protection.



8.1.3.  Surface Water Protection

     Wind, rain, or floods can carry tailings into rivers, lakes,  and

reservoirs.  Pollutants may also seep out of piles and contaminate surface

waters.  We believe that the standards should limit the effects of these

processes on surface water quality.  We expect that implementing the radon

emission limits and the ground water protection requirements will greatly

reduce the potential for contamination of surface water.U>  A pile with

severely restricted radon releases will not be able to release particulates

to wind or water.  Similarly, the ground water protection requirements imply

limited water flow through the pile, which limits flow to the surface as

well as underground.  Thus, implementing the radon emission and ground water

standards may protect surface water.  To assure adequate protection, how-

ever, we propose to require that surface water not be degraded by tailings

after disposal  of the piles.  This means that  the tailings disposal  site

should not cause increases in the concentration of harmful substances in


surface water.



     We considered banning any release of pollutant, to surface water.

This may  be more difficult to implement  than the selected standard,
      (OHowever, .recent  studies  (•-.•-^".S?contaminant, upward,
 Processes  occurring in tailings  piles  «n°     ._,;_ designer, must
 perhaps  even tto-*««  «"»»•.   STSkSSToFESw ««~«»
 carefully  consider this  possibility,   ine w F        .
 intensively investigating  a variety of disposal methods.
                                     8-17

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however, since it would require showing that not even microscopic releases




will occur.  Our chosen standard requires any potentially harmful




contaminant streams from the tailings to have lower concentration of




contaminants than the surface water they may enter.  The standard applies




to all harmful contaminants from tailings, and some of them are certainly



present only in very low concentrations in surface water.  Satisfying the




standard will therefore require strict limits on releases to surface water



of at  least these latter substances.  In practice, we expect that the means




used to inhibit pollution of surface water by harmful contaminants that are




already present  in  low concentrations will restrain  the movement of most




other  substances as well.  The standard, then, will be very protective of



surface water.








     We have  chosen to apply  the  standard to "navigable waters"  as  defined




 in an EPA Federal Register notice (44 F.R.  32901,  June  7,  1979).   This




 definition was adopted for EPA's  regulations under the  National  Pollutant




 Discharge Elimination System, 40 CFR 122.3(t).  In essence,  it includes all




 surface waters the public may travel on,  enter, or draw food from.




 However,  there is no formal relationship between EPA's standard under




 PL 95-604 and regulations under the National Pollutant Discharge




 Elimination System; either nay be changed without affecting the other.








 8.1.4  Remedial Action for Existing Ground Water Contamination




      There is evidence of limited ground water contamination at some of the




 inactive sites, but the prospects for long-term contamination have not been




 fully assessed.  The proposed ground water protection standards apply only






                                      8-18

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to releases from tailings that may occur after disposal of the piles.  It



may sometimes be possible to improve the quality of an already-contaminated



aquifer, but we believe a generally applicable requirement to meet pre-set




standards is not feasible.







     The Department of Energy will prepare Environmental Impact Statements



or Environmental Assessment reports for each site to support the decisions




ifc will reach, with NEC's concurrence, on necessary remedial actions to



satisfy the standards.  We believe that disposal methods that satisfy the




standards will avoid any ground water problems caused by future releases



from the piles for as long as the standards apply.  We expect DOE to con-



sider the need for and practicality of controlling contaminants that have



already seeped into the ground under  the  tailings pile, and to apply techni-




cal remedies that are found justified.  Institutional controls should also



be applied.  If tailings  are  found to be  contaminating ground water that  is




being used, we would expect DOE to provide alternate water sources or other



appropriate remedies.  We note that PL  95-604 will terminate DOE's authority




to do so as a remedial action seven years after we promulgate standards,



"nless Congress extends the period.   However, Sec. 104(f)(2) of PL 95-604



Provides for Federal custody  of the disposal sites under NRC licenses after



the remedial action program is completed.  The  custodial agency is author-



ized to carry out such monitoring, maintenance, and emergency measures as



the NRC may  deem necessary to protect public health.  We expect NRC's




requirements will be sufficient to ensure detection of any contamination  by



the tailings  of usable ground water near  the disposal  sites, and  to  cause
                                     8-19

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the custodial agency to take such measures as may become necessary to avoid




any significant public health problem.








8.1.5  Period oj Applj.catj.on of^Disposal Standard s




     Congress recognized that uranium mill tailings are hazardous for a




long time, and directed EPA to provide long-term public protection from




these hazards.  We propose requiring a reasonable expectation that the




radon emission and water protection standards for disposal of tailings




piles will be satisfied for at least one thousand years.








     Any choice is partly arbitrary; there are no rules or precedents to




guide the decision.  Neither does scientific analysis point uniquely to one



period over  another.









     We have concluded that it would be impractical to apply uranium mill




tailings  standards for periods  as long as  10,000 years.  Providing a




reasonable expectation of compliance with  the standards over such long




periods,  if  possible  at all  for  tailings,  could be done only if  they were




buried several hundred feet or more beneath  the surface.  During such long




time periods, climates change markedly and land  surfaces may be  denuded,




severely  uplifted, or otherwise  considerably transformed.  Deep  below the




surface,  severe  changes  are likely  to be  more gradual and  predictable.   For




reasons described earlier,  the  practicability of  deep burial of  uranium




tailings  is  uncertain.   Yet,  if strict  standards  were to  apply for  as  long




as 10,000 years  or more, no other disposal method would seem possible.
                                     8-20

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     With tailings disposed of at or near the earth's surface it appears

feasible to meet the standards for one thousand years or more.   The primary

threat during this period is flooding.  Methods of protecting tailings

against floods and other natural disruptions appear to be available.   These

methods, however, may not be applicable at every existing inactive site; for

long-term flood protection, for example, some piles might have  to be moved.




     Standards applying for less than one thousand years would be easier to

satisfy, and might result in some cost savings.  The state-of-the-art of

Judging the future performance of a given disposal system does not support

naking fine distinctions, however.  Therefore, the savings would be small

unless the period of application were only a  few hundred years.  Institu-

tional control methods such as recordkeeping, maintenance, monitoring, and

land-use restrictions are useful adjuncts to  an adequate disposal  system,

Providing greater protection than the standards require, and regulating

^liberate disruptions of the  tailings by people.(D  We do not believe,

however, that they  should be  relied upon for  periods  longer  than  a century,

a*d are inappropriate for long-term control.   Institutional control methods

should not  replace  use  of  adequate  long-term physical disposal  methods.
      CDpor  example,  Sec.  104  of  PL.95-694  ^xcxpates  that  subsurface
 minerals  at  a tailings  disposal site might be  used.   It f °vlde*'  ™*^er
 that  any  tailings  disturbed by such  use  "will  be  restored  to  a  safe and
 environmentally sound condition." We propose, therefore,  to  apply the
 disposal  standards to the  use  of  any subsurface mineral rights  acquired
 under the provisions  of Sec. 104(h).
                                     8-21

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     We believe that one thousand years meets the Congressional criterion
that "the remedial action must be done right the first time."  A thousand-
year standard does not mean that our concern for the future is limited to
one thousand years; it reflects our judgment that the disposal standards
must be practical.  Based on existing knowledge of control methods and
natural processes, we believe it unreasonable to generally require longer
protection under this remedial program, because adequate methods for demon-
strating compliance are not clearly available and may be very costly.  We
consider it likely, however, that the implementers of the standards will
require longer protection at some piles, based on site-specific evaluations
of disposal methods and their costs.


     The disposal standards could be viewed as performance standards,
stating conditions to be satisfied without addressing the means.  Compliance
could be verified by monitoring, and assured through maintenance.   But fun-
damentally, they are design standards.  They are minimum requirements that
the designers of a disposal system should plan to satisfy over the full
period of their application.  The "reasonable expectation" for meeting the
limits specified in the standards will be established by considering the
physical properties of the disposal system, not by relying on institutional
methods.


8.2  Cleanup Standards
8.2.1  Open Lands
     The proposed standard requires that for any open land contaminated
with tailings, the average radium concentration in any 5-centimeter

                                    8-22

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 thickness  shall  not  exceed 5 pCi/gm after cleanup.   These conditions provide




 a high degree  of protection from tailings at  inactive  uranium processing



 sites, and are not unreasonably burdensome to implement.   The protection




 achieved will  often be greater  than  is apparent  from the  standard,  since




 the radium concentration  of any material  not  removed will often  decrease




 sharply with depth.  After  the  required cleanup, such a site will be little




 more hazardous than  a similar area which  never had a tailings  pile.








     Locating contaminated  soils with concentrations less than 5 pCi/gm



 would require extensive surveys and  lengthy measurement procedures.  Incre-




 asingly large land areas would  need  to be  stripped in order to lower the




 radioactivity much below  5  pCi/gm.   Doing this would provide very little




 Sain in health protection,  since such slightly contaminated soils are




 usually thin layers containing  little total radium.  To keep sampling costs




 within reason, and to avoid having to clean large areas which contain little




 radioactivity, the proposed  final standard therefore requires  that  for any




 °Pen land contaminated with tailings, the  average radium concentration shall




 n°t be more than 5 pCi/gm after cleanup.   The  contamination which remains




 after such cleanup will  have less than five times the radon release of aver-



 age soils.  It could also cause  a gamma radiation dose of below 80 millirad




 Per year  to a person who spends  100% of the time outdoors  on the  site.




 These levels of radon emission  and gamma  radiation are within the variations




 that occur in undisturbed land areas.  We believe that  the actual radon and




gatnma ray levels  after cleanup will usually be much less than the maximum




Possible  under these  standards.
                                     8-23

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     For contaminated material located more than one foot beneath the




surface of open land,  our proposed standard requires cleanup if the average



radium concentration over any 15-cm thickness is greater than 5 pCi/gm.




Practical measurement  instruments cannot find buried material of this



concentration in a layer any thinner.  We expect that this standard for



buried material will serve mostly to define the edges of buried tailings



deposits, because the radium concentration in tailings is usually much



higher than 5 pCi/gm.








     In most cases, concentrations a few times higher than the proposed



standard allows would cause only a slight  increase in risk.  Since concen-



tration usually declines rapidly with depth, even a standard requiring



removal of material until the radium concentration level reaches 10 or




20 pCi/gm would be protective.  Unusual distributions of radium would be



much more significant, however, and areas with 5 to 20 pCi/gm are clearly



above ordinary background levels.








     Surveys at inactive processing sites indicate that it should cost



little more to implement the proposed standard than one permitting levels



two to four times higher.  The proposed standard is EPA's judgment of the



most stringent cleanup condition that may  reasonably be required uniformly



for all the inactive mill sites.








     The proposed standard addresses future as well as present hazards and



uses an intrinsic property of tailings  that can be easily measured.  We




considered other forms for the standard, such as limiting the residual






                                     8-24

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surface gamma radiation, the radon release rate, or the predicted



concentration of radon decay products in future buildings on the land.  All



these would restrict the residual hazard, but they would be harder to apply



to material which has been buried and might be uncovered later.








     We expect that the rules developed to implement this standard will




'elate the concentration of radium in soil to other conveniently measured



quantities.  We also expect that appropriate sampling techniques will be




established to locate and identify tailings material,  determine its



concentration of radium, and verify compliance with the standard.  Any such




rules must insure that the standard is not met simply by dispersing the



material to achieve a lower concentration.








8-2.2  Buildings



8.2.2.1  Indoor Radon Decay Product Concentration Standards



     Exposure even to normal indoor radon decay product concentrations




carries some health risk, but we believe Congress intended that people



should not have to bear an unreasonable increase in this risk due to



tailings.  Remedial actions will be required when a building affected by



tailings exceeds the levels we set as the remedial action standards.  When




remedial actions are finished, the level must either not be exceed, or



tailings must not be the cause of any remaining excess.  We believe that




expressing the indoor radon decay product standard in terms of total



concentration of these products is the only workable form, as the following




discussion indicates.
                                     8-25

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     Indoor radon decay product concentrations in normal buildings vary




widely.  Tailings near or under a building may be identified by gamma ray




measurements, historical records, visual inspections, or specimen analysis.




Because of the fluctuations in normal indoor radon levels,  however,  it is



impossible to tell what the concentration of radon decay products would be




without the tailings.  Small elevations when tailings are present cannot be



distinguished from normal background levels.  Further, contaminated




buildings vary in location, design, materials, and patterns of use,  all of




which affect the indoor radon decay product concentration.  It is imprac-




tical to determine an expected background value for a particular building,




either from measurements of unaffected buildings or by any other means.








     For these reasons, an action level expressed in terms of an increment



over the background radon decay product concentration cannot be implemented




easily.  We prefer an action level in terms of the total indoor concentra-




tion, which is directly measurable.  With a fixed measurement method, this




standard gives an unambiguous criterion for remedial action for any



building affected by tailings.









     We also considered expressing the standard in terms of the quantity or



concentration of tailings near the building, or the gamma radiation they




produce.  There is no sure way, however, to relate these quantities to




indoor radon decay product concentrations.  This is a critical deficiency,



because the radon products are the basic hazard.
                                     8-26

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     A standard for total concentration of radon decay products provides




the same action level for all affected buildings, though normal concentra-



tions in one affected area may tend to be higher than in another.  While




normal indoor ration decay product concentrations vary with natural radium




concentrations in soil, soil porosity, and other factors, we know of no way




to take them into account in the standard.  In these circumstances,  we




consider the regional protection inequity minor, as long as the action




level we choose is within the normal range of levels in the affected areas.








     We believe that the proposed remedial action level of 0.015 WL




(including background) for occupied or occupiable buildings is the most



Protective level that can be justified for the PL 95-604 remedial action




Program.  It is about the same as that applied to homes and schools over



the last seven years in the Grand Junction remedial action program, because




the action level there was 0.01 above an "average" background value taken




fls 0.007 WL.  Experience in the Grand Junction program and studies performed




by EPA for basementless homes in Florida indicate that remedying concentra-




tions greater than 0.015 WL is usually practical in view of technical and




cost considerations.  In some situations, a lower action level might be jus-



tified.  However, studies of normal houses with basements in Grand Junction,




New York, and New Jersey indicate that about 10% or more are above 0.015 WL.




We have concluded that efforts to reduce levels significantly below 0.015 WL




by removing tailings would often be unfruitful, and the funds expended




wasted.
                                     8-27

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     Although indoor radon decay product levels exceeding 0.015 WL can occur


in the absence of uranium mill tailings,  these proposed standards are


explicitly for remedial actions at sites  designated under PL 95-604.(1)


PL 95-604 is clearly directed at potential health problems due to tailings,


and not to similar hazards from other causes.   We are not calling for


lengthy and expensive procedures to determine whether any tailings are


present when the level is only slightly exceeded.  Professional judgment in


the field must be relied upon in such cases to implement the standards


sensibly.  If the allowable level is still exceeded after all apparent


tailings have been removed or otherwise prevented from affecting the


interior of the building, then the standard requires no further remedial

measures.





8-2.2.2  Standards for Indoor Gamma Radiation


     The proposed limit on indoor radon decay product concentration is


based on the hazard from breathing air containing these products.  Tailings


also emit gamma radiation, however, which can penetrate the body from the


outside.  We expect that the indoor radon product concentration standards


generally will be met by removing the tailings from the buildings and that


this will eliminate any indoor gamma radiation problem.  It is only in


unusual cases that a standard for limiting gamma radiation exposure may be

needed.
nonoaL *? P«ticular, the proposed remedial action standard should not
necessarily be taken as an appropriate design goal for indoor radon decay
product concentration in new housing
                                     8-28

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     It will often be possible  to meet  the  radon decay  product  standards

without removing the tailings.  Removal is  the remedial method we wish most

to encourage, however, because  of its positive and  long-lasting effective-

ness.  To this end, we propose  an action level for gamma radiation of

0.02 mR/hr above background, (1) which allows a limited degree of

flexibility in the methods  for  reducing indoor radon decay product concen-

trations.  On the other hand, reducing the  standard much below 0.02 mR/hr

would virtually eliminate flexibility in remedial methods, and provide only


a small additional health benefit to those  few individuals who might be

affected.  If the occupants of  the building were present 75% of the time,

the proposed standard would allow gamma radiation doses from the tailings

of about 130 mrad per year.  This is about  twice the average annual


background dose from gamma rays in the regions near the piles.




8.2.2.3  Radiation Hazards Not Associated with Radium-226

     The total protection that a standard based on radium-226 affords

depends on the extent to which radium has been separated from other radioac-

tive substances during ore processing.  Radium-226 concentrations in the

residual material may not adequately measure the radiation hazard in all

cases.
     For the reasons discussed in Sec. 7.3, we cannot yet say in all cases

    effective cleanup standards based on radium-226 will be in controlling
     (•^Indoor background levels of gamma radiation are easier to
determine and less variable than is the case for measurements of radon
decay product concentration.
                                     8-29

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U-235 decay products and thorium, and we are not in a position to set a




separate standard for them.  It is our judgment, however, that adequate



protection would be provided if, after cleanup, the total risk from all




uranium and thorium isotopes and their decay products pose no greater risk




than the proposed final cleanup standards allow for radium-226 and its




decay products.   The degree to which any particular site would need to be




cleaned in order to meet this condition will have to be determined following




detailed studies of tailings at that site,  and further evaluation of the



hazard pathways  there.
                                     8-30

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                          References for Chapter 8

(AE 77)  Atomic Energy Control Board (of Canada),  April 7, 1977, "Criteria
         For Radioactive Clean-up in Canada," Information Bulletin 77-2.

(CH 79)  Chappel, W.R., e£ al^, 1979, "Human Health Effects of Molybdenum
         in Drinking Water," USEPA Health Effects  Research Laboratory
         Report, EPA-600/1/79-006.

(EP 76)  U.S. Environmental  Protection Agency,  1976,  "Quality Criteria for
         Water," Report EPA-440/9-76-023.

(EP 78)  U.S. Environmental  Protection Agency,  June 1978, "State of
         Geological Knowledge Regarding Potential  Transport of High-Level
         Radioactive Waste from Deep Continental Repositories," Report
         EPA/520/4-78-004.

(FB 76-78)  Ford, Bacon, and Davis, Utah, Inc., "Phase II-Title 1,
            Engineering Assessment of Inactive  Uranium Mill Tailings" 20
            contract reports for Depart of Energy  Contract Nol
            E(05-l)-1658, 1976-1978.

(FR 79)  Federal Register (44 F.R. pp.  23738-23767),  April 20, 1979.

(GJ 79)  Grand Junction Office, February 1979,  "Progress Report on the
         Grand Junction Uranium Mill Tailings Remedial Action Program,"
         U.S. Department of  Energy Report DOE/EV-0033.

(GS 78)  U.S. Geological Survey, 1978,  "Geologic Disposal of High-Level
         Radioactive Wastes  — Earth-Science Perspectives," Circular  779.

(HE 78)  Healy,  J.W., and Rodgers, J.C.,  October 1978, "A Preliminary Study
         of Radium-Contaminated Solid," Los Alamos Scientific Laboratory
         Report  LA-7391-MS.

(NE 78)  Nelson, John D., and Shepherd,  Thomas  A.,  April  1978,  "Evaluation
         of Long-Term Stability of Uranium Mill Tailing Disposal
         Alternatives," Civil Engineering Department,  Colorado State
         University, prepared for Argonne National Laboratory.


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                             9:  IMPLEMENTATION








9.1  Administrative Process



     Public Law 95-604 requires that the Secretary of Energy implement



EPA1s standards for uranium mill tailings from inactive processing sites.




The Secretary or a designated party will select and perform remedial



actions for designated processing sites in accordance with the standards,




with the full participation of any State which shares the cost.  The



Nuclear Regulatory Commission (NRC) shall concur in selecting and per-



forming the remedial actions, and affected Indian tribes and the Secretary



of the Interior shall be consulted as appropriate.  The Federal Government



and the States will bear the costs of the remedial actions as prescribed




fey law.








*«1.1  Disposal Standards



     The disposal standards will be implemented by showing that the dispo-



sal method can reasonably be expected to satisfy the radon emmission limits



and water protection provisions of the standards for at least one thousand



years.  This expectation should be founded upon analyses of the physical



Properties of the disposal system and the potential effects of natural



Processes over time.  Computational models, theories, and expert judgment




will be major tools in deciding that a proposed disposal system will



satisfy the standard.  Post-disposal monitoring can serve only a minor



*ole in confirming that the standards are satisfied.   Where measurements



are necessary to determining compliance, they may be performed within the




accuracy of available field and laboratory instruments used in conjunction




with reasonable survey and sampling procedures.

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9.1.2  Cleanup Standards




     The Department of Energy (DOE) will need to make a radiation survey of



open lands and buildings in areas believed to have tailings, and determine




whether the standards are being exceeded because of tailings.  After taking



remedial action to reduce radiation, compliance with the standards will




have to be verified.  DOE, working with NRC and the participating State,



will need to develop radiological survey, sampling, and measurement proce-




dures to determine necessary and practical cleanup actions,  and to certify




the results of the cleanup.  We have published elsewhere the general




requirements for an adequate land cleanup survey (EP 78a).








     These procedures are important in making the standards effective.  In




view of this, we considered providing more details of the implementation




as part of our rulemaking.  To give more flexibility to the implementers,




we chose not to do so.  We believe this was warranted because conditions




at the various processing sites vary widely and are incompletely known.




The  following clarifies our intentions and should help to avoid the




unproductive use of  resources  that could result if the standards were




interpreted so strictly that complying with them would be unreasonably



burdensome.









9.1.2.1  Purpose of  cleanup standards




     The purpose of  our standards  is to protect public health and  the




environment.  We designed them for adequate protection using search and




verification procedures with reasonable cost  and technical  requirements.




 Since, for example, we intend the building cleanup standards to protect






                                      9-2

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 people,  measurements in such locations as crawl spaces and furnace rooms
 are  inappropriate.*  Remedial  action  decisions  should be based  on radiation
 levels  in occupiable parts of the buildings.   The standards  for cleaning
 up land  surfaces are designated  to limit  exposures of  people to gamma
 radiation and to radon decay products  in  future buildings.   In most
 circumstances,  failure  to  clean  a few  square feet of land contaminated by
 tailings would be  insignificant.  Similarly, in attempting to  find tailings
 beneath  the surface  on  open land,  reasonableness must  prevail  in deter-
 mining where  and how deeply to search.  Requiring proof that all the
 tailings had  been  found would be unreasonable.   In all applications of our
 proposed cleanup standards, search and verification procedures which
 provide  a reasonable assurance of compliance with the  standards will be
 adequate.  Necessary measurements may  be  performed within  the  accuracy of
 available  field and  laboratory instruments used  in conjunction with
 reasonable survey  and sampling procedures.  We are confident that  DOE and
 NRC, in  consultation with  EPA and  the States, will adopt implementation
 Procedures consistent with our standards.

 9»2  Exceptions
     We  believe that  our proposed  standards are the strictest  that are
Justified  for general application  at all the inactive uranium processing
sites covered by PL 95-604.  However, providing greater protection  may be
reasonable at specific sites.  We urge the impleraenters to lower the
residual risk as far below the required level as is reasonably achievable.
                                     9-3

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     In the decades since tailings at inactive sites were deposited,



weather and people have created a wide range of problems.  The standards




may be unreasonably strict in some exceptional circumstances.   If meeting




the standards is impossible, or if some clearly undesirable health or




environmental side effects are unavoidable,  applying the standards would



be unjustified.  Tailings may be inaccessible to the equipment needed for




their removal, or workers might be endangered in trying to remove them.




In such cases, applying the standards should be reconsidered.  Similarly,




disturbing scarce desert vegetation and soils may be unjustifiable where



the standards are only slightly exceeded.








     Because the scale of material-moving activity is so great, the




possibility of serious harm to both workers and the general public from




accidents associated with transporting an entire tailings pile to a new



disposal site deserves particular consideration.  Relocating a pile should




be considered whenever it may be impractical to satisfy all the disposal




standards at the original location.  However, circumstances might be such




that one would not expect the standards to be greatly exceeded within a



thousand years, and that substantial human exposure to any resulting




pollution would not necessarily occur.  If all practical transport methods



would probably cause serious harm to people from accidents, and if this




and other risks associated with the transportation system are large




enough, the near-term danger may outweigh the additional long-term benefits




of full rather than partial compliance with the standards.  By carefully




considering all these factors for each tailings pile where the issue
                                     9-4

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 arises, exceptions to the disposal standard could be justified because of




 the degree of unavoidable endangerment in attempting full  compliance.








      We do not consider the current remoteness of a pile from population




 centers sufficient by itself to  justify relaxing  the disposal  standards.



 Even small numbers of people nearby require protection,  and the population




 of  an area could  increase considerably over the one-thousand-year  period




 during which the  standards apply.   Furthermore, radon released from




 tailings piles  travels  long  distances.








      We also do not consider cost  a reason for noncompliance with  the




 standards  unless  the  cost  is very high  or  the  benefit very  small.   But it




 may  not make sense to spend  a great deal  of money,  for example,  to clean




 UP an  infrequently  occupied building where  the standards are only  slightly



 exceeded.








     To allow PL 95-604 to be implemented reasonably in all of the varied




 circumstances, we  are proposing criteria which the  implementers may use to



 determine whether particular circumstances are exceptional.  In such excep-




 tional  cases, DOE may select and perform remedial actions which come as




 close to meeting the standards as is reasonable.   In selecting such




 remedial actions, DOE shall ask any property owners and occupants  for




 'heir comments; the concurrence  of  NRC shall be required,  and  DOE shall




inform EPA.
                                     9-5

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9.3  Effects of Implementing the Standards



9.3.1  Health




     The proposed standards reduce average radon emissions of the tailings



piles by more than 99% for one thousand years.  Extrapolating the current




rate of lung cancer deaths over that period,  we estimate applying the



standards will prevent about 2,000 premature lung cancer deaths.








     Some people now living very near tailings piles could bear a risk of



premature death due to lung cancer of several chances in 100.  Under the




disposal standards, people living in comparable locations during the next



thousand years will bear a risk from the pile of about 1 chance in 10,000.








     After remedial actions are completed on buildings eligible under



PL 95-604, their occupants will be subject to radon decay product concen-



trations of less than 0.015 WL (including background), and gamma radiation



exposure rates lower than 0.02 mR/hr.  Their estimated total risk of fatal




cancer due to residual tailings following remedial action will average



less than about 1%.  This is within a normal range of fluctuation for risk



from indoor radon decay products in the absence of tailings.








     After remedial actions on eligible open land, residual contaminated




materials will have less than five times the radon release of average



soils.  It could cause a gamma radiation dose of less than 80 millirad per




year to a person who spends 24 hours a day outdoors on the site.  These



levels of radon emission and gamma radiation are within normal variations




in undisturbed land areas.  We believe that the actual radon and gamma ray






                                     9-6

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 levels after cleanup will usually be much less than the maximum permitted

 by these standards.



 9.3.2  Envi r onment al

     Since the proposed standards call for effective control for at least

 °ne thousand years, dispersal by floods, erosion, or mass movement should

 Qot reasonably be expected to occur during that period.  Releases  of radon

 gas to the air from the site will be slightly above average, but within a

 normal range.   High-quality ground water will be protected for a wide range

 °f uses, including drinking} surface waters and lower-quality ground water

will not be degraded by the tailings.



     Contaminated open land will be subjected to scraping and digging by

 the cleanup operations.  Generally these activities will occur immediately

 adjacent to the piles, but off-site areas where tailings have been deliber-

 ately used also will be affected.   Disposal  operations may require large

Quantities of clay and soil for covering the tailings, depending on the

disposal method.  The environmental effects  of obtaining these materials

will vary with the site.  The general ecological effects of land cleanup

and restoration operations are examined in detail in an EPA report

    78b).
Q ,
       Economic

     Estimating the total cost of disposing of all the tailings piles

e*igibie under PL 95-604 is difficult, primarily because methods will be

chosen specifically for each site.  We estimate the cost (in 1978 dollars)


                                     9-7

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of covering an average pile to meet the proposed radon emission standard
as $1 million to $6 million if the  existing site is  suitable,  or  $6 million
to $13 million if the pile must be  moved.   The total disposal  cost for all
sites would then be $21  million to  $273 million.  Deep burial  and chemical
treatments could be considerably more expensive.

     Cleanup costs for open land and buildings have  been estimated using
interim cleanup criteria as about $10 million (see Section 7.4).   Even
allowing for increased costs under  the proposed standards,  disposal is
still by far the largest cost component of the remedial action program.

     Although difficult  to estimate, the total cost  of the  entire program
probably will be $200 million to $300 million.  The Federal government
will assume a 90% share, and any State government in which  an  inactive
processing
site is located will pay 10%.  We expect the expenditures will be spread
over the seven-year authorization of the program.  Most of these  expendi-
tures will occur in the  regions where the  tailings are located.  Their
significance depends on the amount  expended, the size of the local
economy, and the availability of necessary equipment and labor.

     Contaminated land and buildings might be made available for  use as a
result of the cleanup program.  On  the other hand, moving tailings to a
new location removes the new disposal site from other potential uses.
                                     9-8

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     In summary, the program could result in net economic benefits of




decreased unemployment and increased business activity for the regions



where the piles are located.  We expect little or no perceptible national




economic impact because the total seven-year expenditures will be small



compared to the annual Federal budget, (less than 0.06% of 1978 budget),




the annual Gross National Product (less  than 0.01%  of 1978 GNP),  and  the



construction industry (less than 0.5% of 1978 billings).








9-4  The Proposed Standards




     The proposed standards are presented  in Appendix D.
                                    9-9

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                          References  for Chapter 9


(EP 78a)   "Response  to  Comments:   Guidance  on Dose  Limits  for  Persons
          Exposed to Transuranium Elements  in  the General  Environment,
          EPA Technical Report  520/4-78-010.

(EP 78b)   "The Ecological Impact  of Land Restoration and Cleanup,"
          August 1978,  EPA Technical  Report 520/3-78-006.
                                     9-10

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            APPENDIX A
           Reserved for
Comments and Responses to Comments

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         APPENDIX B
Development of Cost Estimates

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                                APPENDIX B

                       Development of Cost Estimates

                                                                  Page

B.1  The Average Inactive Uranium Mill Tailings Pile  	    1

B.2  Development of Unit Cost Computations	    |
     B.2.1  Earth Work	
     B.2.2  Caps and Liners	   ^
     B.2.3  Stabilizatibn	   ^
     B.2.4  Fencing	   13
     B.2.5  Irrigation	
     B.2.6  Matrix Fixation	   17
     B.2.7  Tailings Transportation  	   1Q
     B.2.8  Discount Rate	    «
     B.2.9  Present Worth of Future  Costs 	
     B.2.10 Land Costs  .....  	

B.3  Cost Estimates For Disposal  Options  	
     B.3.1  Option  1 - No Radon Control	    *
     B.3.1.1  Option 1a - Fencing	•  *  *  *     ,
     B:3.1.2  Option 1b - Stabilization  With No Radon Control  .  .   21
     B.3.2  Controlling Radon Emissions  with an Overburden  ...   «?«•
     B.3.3  Option  2 - Existing Surface  Site,  Covered
              to Control Radon Emissions 	   27
     B.3.3.1  Dimensions	   27
     B.3.3.2  Cost  Estimates	   -^
     B.3.3.3  Use of Tables B-7 Through  B-11   .  .  .  •  '  '  '  '  '  '
     B.3.U  Option  3 - New Site,  Below Grade,  with Liner if      ^   ^
              Needed	*	|   ^5
     B.3.4.1  Requirements   ••••••;  	  '   37
     B.3.M.2  Dimensions and  Cost Estimates 	
                                                             ...   39
 B.4  Other Disposal Methods	•  •  •••:,*           QQ
     B.4.1  Extraction  and Disposal of Hazardous Materials  ...   |9
     B.U.2  Long-Term  Radon  and  Hydrology Control 	
                                                         	   5M
 References  for  Appendix  B  	
                                      B-2

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                                  FIGURE

                                                                    Page

B-1   Cross-Section of the "Average" Mill Tailings Pile	    5
                                  TABLES
B-1   Unit Costs	7,8
B-2   Estimated Capital Costs for Matrix Fixation  	  15
B-3   Annual Operating Costs for Matrix Fixation  	   16
B-1   Costs and Dimensions of Particulate Control 	   23
B-5   Thickness (meters) of Cover Required to Reduce Radon to
        Control Level 	   25
B-6   Control Methods for Disposal Option 2 	   26
B-7   Costs and Dimensions for Disposal Option 2 with Control
        of Radon to 100 pCi/m2/sec	   28
B-8   Costs and Dimensions for Disposal Option 2 with Control
        of Radon to 10 pCi/m2/sec	   29
B-9   Costs and Dimensions for Disposal Option 2 with Control
        of Radon to 5 pCi/m2/sec	•	   30
B-10  Costs and Dimensions for Disposal Option 2 with Control
        of Radon to 2 pCi/m2/sec	   31
B-11  Costs and Dimensions for Disposal Option 2 with Control
        of Radon to 0.5 pCi/m2/Sec	   32
B-12  Control Methods for Disposal Option 3 	   36
B-13  Constant Costs for Below-Grade Disposal of Uranium Mill
        Tailings	   38
B-14  Variable Costs and Dimensions for Disposal Option 3 with
        Control of Radon to 100 pCi/ra2/sec	   10
B-15  Variable Costs and Dimensions for Disposal Option 3 with
        Control of Radon to 10 pCi/m2/Sec	   11
B-16  Variable Costs and Dimensions for Disposal Option 3 with"
        Control of Radon to 5 pCi/m2/sec	   12
B-17  Variable Costs and Dimensions for Disposal Option 3 with*
        Control of Radon to 2 pCi/m2/sec	   13
B-18  Variable Costs and Dimensions for Disposal Option 3 with"
        Control of Radon to 0.5 pCi/m2/sec	   W
B-19  Costs of Nitric Acid Leachate Disposal  ....*!.*"!*!   17
B-20  Costs of Residual Tailings Disposal .	   19
B-21  Cost Estimates of Deep Disposal When a Nearby Open-pit
        Mine Is Available	   51
B-22  Cost Estimates of Deep Disposal When a Nearby Underground
        Mine Is Available	             53
                                     B-3

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                                 APPENDIX  B



                       Development of Cost Estimates








B.1  The Average Inactive Uranium Mill Tailings Pile



     To develop cost estimates of the various uranium mill tailings



disposal methods, we employed an "average" inactive uranium mill tailings



Pile, with dimensions based upon the average dimensions found at the 21



inactive uranium mill tailings sites.  The tailings area, volume, and



weight dimensions have been computed from the information found in the



Ford, Bacon and Davis, Utah, Inc, engineering reports on the inactive



uranium mill tailings sites (FB 76-78).







     The "average" pile has the configuration of a truncated regular pyra-



mid with a lower base of *»36m on a side, including embankments.



Figure B-1 gives a cross section of the uranium mill tailings impoundment



area.  The mill tailings pile covers a surface area of a little more than



19 hectares (190,000m2, or 47 acres).  The embankments contain



78M,OOOm3 (1,026,000 yd3) of uranium mill tailings, weighing



1,325,000 short tons.  The tailings are assumed to be 5.0m deep within



the embankments.  We further assumed that when the uranium milling



operations ceased, the tailings pile was  left flat on top but uncovered,



and there is evidence of both wind and water erosion.  Tests indicate



that tailings have migrated as far as 1,000m from the "average" tailings




Pile.
                                     B-fl

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                                       FIGURE B - 1
CD
tn
                   ////////////77//////1///
              CROSS-SECTION OF THE "AVERAGE" INACTIVE URANIUM MILL TAILINGS FILE

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B.2  Development of Unit Cost Computations
     The unit costs used for estimating the costs of the disposal options
are presented in Table B-1.  They are average costs and represent the
expected monetary values that will be encountered while completing indi-
vidual tasks, or purchasing specific items necessary for the various
uranium mill tailings disposal methods considered in this report.  The
unit costs are in 1978 dollars and reflect the economic conditions of
that year.

     The procedures used to derive the unit costs are as follows:

          a. Any costs not already in 1978 dollars are adjusted
to reflect 1978 values using an appropriate price index (usually the U.S.
Department of Commerce Composite Construction Cost Index published in the
Survey of Current Business).
          b. When only one source for the cost of an item is available,
that value is used.
          C. When more than one cost estimate is available, the average
°f these values is used.

B»2.1  Earth Work
     The sources for computing the costs for various types of earth work
    Dodge (DO 78), Means (ME 77), and .the NRC-DGEIS (NR 79).
                                     B-6

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                                 TABLE B-1

                                Unit  Costs
     Task

1.   Earth work

     a.  Below-grade excavation in normal soil
         Below-grade excavation in shale
     b.  Dragline excavation and loading
     c.  Excavate,  load, and haul
     d.  Spread and compact
     e.  Haul, dump, spread, and compact

2.   Caps and Liners

     a.  Clay (when available)
     b.  Clay (purchase required)
     c.  Synthetic
     d.  Asphalt emulsion (1/2" thick)

3.   Stabilization

     a.  Vegatation (when soil available)
     b.  Vegatation (when purchase required)
     c.  Riprap (.5m thick)
     d.  Gravel (.5m thick)
     e.  Chemical

4.   Fencing

     a.  Chain-link fence 5 to 6 feet high
     b.  Security fence (prison grade)

5.   Irrigation

     a.  Equipment  (excluding pumps)
     b.  Annual operating costs
     c.  Submersible pump
Cost (1978 dollarsl
     $1.63/ra3
     $3.10/m3
     $1.53/m3
     $1.13/m3
     $0.38/m3
     $1.33/m3
     $2.07'/m3
     $5.00/m3
     $1.76/m2
     $0.75/m2
     $2.51/m2
    $12.90/m2
     $2.57/m2
    $29.69/m
    $8l».51/m
$1,070/hectare
$  273/hectare
$1,000 each
                                     B-7

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                                TABLE B-1  (continued)

                                Unit Costs
     Task

6.   Matrix Fixation

     a.  Cement with thermal evaporator
           Capital costs
           Annual operating costs
     b.  Cement with filter bed
           Capital costs
           Annual operating costs
     c.  Asphalt with thermal evaporator
           Capital costs
           Annual operating costs
     d.  Asphalt with filter bed
           Capital costs
           Annual operating costs

7.   Tailings Transportation

     a.  Truck
     b.  Rail
     c.  Pipeline (7" diameter)
            Capital equipment and right-of-way
            Operating costs

8,   Discount  rate  (real  rate of return)

9.   Future Costs

     a.  Vegetation stabilization
           Annual operating cost
           Irrigation equipment
           Submersible  pump
     b.  Chemical stabilization
     c.  5-6  foot chain-link  fence
     d.  Security fence (prison  grade)

 10.  Land  Costs  (farmland)
                                                      Cost (1978 dollars)
    $4.75 million
    $6.57 million

    $6.55 million
    $2.14 million

    $7.90 million
    $8.51 million

    $9.70 million
    $4.07 million
 $0.10/ton-mile
 $0.08/ton-mile

   $63,840/mile
$0.048/ton-mile

        7%
 $3,900/hectare
   $400/hectare
    $2,500 each
$23,800/hectare
   $4.27/m
       $12.17/m

   $781/hectare
                                      B-8

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     There are two types of below-grade excavation, depending on the



consistency of the material being excavated:  normal or shale.  Though



classified as one category, normal below-grade excavation is not



homogeneous; it includes digging in soft soil as well as in various forms



of clay.  Similarly, the costs of excavating in such a variety of soil




types can vary significantly.  As a result, the expected cost for normal




below-grade excavation is $1.63/m3, but may actually range anywhere



between $0.56/m3 and t5.98/m3.  The average cost for below-grade



excavation  of shale, on the other hand, rises to $3.10/m3, and may



range between $2.56/m3 and $3»8l/m3.








     According to Ford, Bacon and Davis, Utah,  Inc. (FB 76-78), a



dragline  method of  tailings excavation  is  required  to  remove  the uranium




mill tailings from  their present site.  This method of tailings




excavation  is assumed  throughout this  report.   Estimates  of dragline




excavation  and loading establish the cost  for removing the uranium  mill



tailings  at $1.53/m3.








     Excavating,  loading,  and  hauling  surface  soil up  to  one  mile  is




expected  to cost  $1.13/m3,  but may be  as  low as $0.92/m3  or  as high



as $1.58/m3.   Spreading and  compacting materials (such as mill



 tailings, top soil, clay,  etc.) will  average $0.38/m3, but may range



 between $0.22/m3 and $0.75/m3.   Finally,  hauling up to one mile,



 dumping,  spreading, and compacting is  expected  to cost $1.33/m3,  and  is



 considered a single task.
                                      B-9

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B.2.2  Caps and Liners
     The sources for unit cost estimates of caps and liners are Dames and
Moore (DA 77), the NRC-DGEIS (NR 79), and Smith and Lambert (SM 78).

     There are basically three types of caps and liners: clay, synthetic,
and asphaltic emulsion.  The major purpose of a cap is to reduce radon
emissions from the mill tailings into the surface environment.  A cap
also affords some hydrologic control by reducing seepage of surface water
into the tailings.  Liners, on the other hand, are used chiefly to
provide hydrologic control beneath the pile.  That is, a liner will
reduce moisture seepage from the mill tailings into the ground water or
ground water infiltration into the tailings.

     Assuming a nearby source of suitable clay (that is, with a large
Proportion of montmorillonite) is available at no cost, a clay cap or
liner can be expected to cost $2.07/m3 to install, but may actually
range between $1.l4/m3 and $2.93/m3.  If a suitable type of clay must
be purchased, an additional $2.93/m3 should be added to the cost of
installing a clay cap or liner.

     Many types of synthetic materials are available which could be used
as a cap or liner for uranium mill tailings (e.g., polyester-reinforced
Hypalon or Polyvinylchloride).  Because these types of caps and liner
require a carefully prepared installation, they can be quite expensive.
                                     B-10

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On average, $4.i»1/m2 is the expected cost of installing a synthetic cap
or liner, but the cost may range between $2.00/m2 and $11.89/m2.

     The least expensive method of providing a cap or liner for uranium
mill tailings appears to be an asphaltio emulsion.  Smith and Lambert
(SM 78) estimate that the cost of applying a 0.5-ineh-thick layer of
asphaltic emulsion costs $7,140 an acre or $1.76/m2.

B.2.3  Stabilization
     All methods of stabilizing uranium mill tailings disposal sites have
a common purpose; that is, to protect against wind and water erosion.
This reduces the quantity of uranium mill tailings that migrate from the
disposal site.  Four methods of stabilization are considered in this
report: vegetation, riprap, gravel, and chemical.

          a.  Vegetation as a stabilizer consists of plants to hold
the surface in place.  The proper installation of vegetation requires
approximately eight inches of suitable surface soil to insure plant
propagation.  Besides seeding, fertilizer, lime, and soil binders are
also necessary to aid plant growth until a ground cover is established.
If it  ts assumed that suitable top soil is available locally, the cost of
providing a vegetation cover will cost $0.75/m2, but may range between
$0.38/ra2 and $1.12/m2.  If top soil and loam must be purchased, then
the cost of vegetation becomes significantly more expensive ($2.51/m2
on average, ranging between $1.U8/m2 and $3-93/ra2).  These cost
estimates do not include the irrigation costs for areas without
                                     B-11

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adequate precipitation.  The capital and operating expenditures



associated with irrigation are discussed later.








          b.  Riprap consists of large stone or concrete chips (1/4 yd3




to 3/8 yd3 in size) in a layer approximately 0.5m thick as a cover on



the uranium mill tailings disposal site.  Riprap is either placed loose




or enclosed in galvanized steel mesh boxes called gabions.  Riprap has an



average installation cost of $12.90/m2.  If placed loose, riprap can



cost as little as $4.78/m2.  But if the ri-prap must be enclosed in



gabions, the cost of a riprap cover may be as high as $25.79/m2.








          c.  Like riprap, gravel provides wind and water erosion protec-




tion for the uranium mill tailings disposal site, and an 0.5m-thick cover




of gravel is assumed to be required for adequate wind and water erosion



protection.  Installing a 0.5m-thick gravel cover costs $2.57/m2, on




average, but ranges between  $2.49/m2 and $2.73/m2.








          d.  Other types of covers, categorized here as chemical




stabilizers, include asphalt, asphaltic emulsion, road  oil, and various



other chemicals.  Although  the  chemical stabilizers appear  to be the



least expensive method of stabilizing  a uranium mill tailings disposal




site  (the average installation  cost is $0.75/m2), the application cost




ranges  widely, between $0.05/m2 and $9.69/m2.  Further, their



long-term stability is untested.   Some methods require  replacement  in



less  than a year while others may  last 20 years or more.  For cost
                                     B-12

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estimates, we assumed that a chemical stabilizer will need replacement



every four years.








B.2.4  Fencing




     Sources for unit costs of fencing are Dodge (DO 78), Means (ME 77),



the NRC-DGEIS (NR 79), and Smith and Lambert (SM 78).








     Isolation of the uranium mill tailings disposal site from intrusion




can be accomplished by a fencfc.  We considered two types of fences in




this report.  A chain-link fence five to six feet high, with or without



several strands of barbed wire on top, costs an average of $29.69/m to




install, but may range between $21.33/m ?nd $49.21/ra.  If more security



is required, a prison-grade security fence 12 to 16 feet high will cost



$84.51/m to install, but may be as low as $73.49/m or as high as




$95.5U/m.  These costs include installation, corner posts, and a gate.



The effective life of these fences is assumed to be one hundred years,




with proper maintenance.  Annual maintenance for the fences is expected



to be cost 1? of the original expenditure for the fences.







B.2.5  Irrigation




     The capital and annual operating expenditures for irrigation used in




this report have been taken from the NRC-DGEIS (NR 79).  All costs are



stated on a per hectare basis, except for submersible pumps.  Annual




operating expenditures for running and maintaining irrigation equipment



are expected to be $273 per year per hectare.  This value includes
                                    B-13

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fertilizer, power, operating labor, maintenance on the irrigation equip-
ment, and ground water analyses.  Installation of the irrigation
equipment, including pumps and miscellaneous valves and nozzles, will
cost $1,070 per hectare.  It is expected that this equipment will need
replacement an average of every 20 years.  In addition, one submersible
pump, at a cost of $1,000 is required for every 20 hectares irrigated.
Replacement of the submersible pumps can be expected every five years.

B.2.6  Matrix Fixation
     Uranium mill tailings could be incorporated into a concrete or
asphalt mixture,  reducing the leachability of the tailings into the
hydrologic system.  A detailed  discussion of the methods and require-
ments for  fixing  uranium mill tailings  in a concrete or asphalt matrix
oan  be found in the NRC-DGEIS (NR  79).

     Detailed breakdowns of the estimated capital expenditures and annual
operation  costs for the various methods of matrix fixation are given  in
Tables B-2 and  B-3.  These tables  have  been taken directly from the
NRC-DGEIS  (NR 79), Tables  11.9  and 11.10, respectively.

     From  a cost  standpoint, significant savings can be realized in
initial  capital costs and  in annual operating expenditures if a cement
rather than asphalt matrix is used.   In addition, the metho'd of drying
the  tailings before incorporation  into  either a cement or asphalt matrix
has  significant cost  implications.  For both concrete  and asphalt

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                                 TABLE B-2
                Estimated Capital Costs for Matrix Fixation3^

                        (thousands of 1978 dollars)
                                Thermal Evaporator     Filter    ^
  Equipment	Cement     Asphalt   Cement   Asphalt

Sand washing and drying        $  230    $  230     $  230    $  230

Lime neutralization               670       670        670       670

Slimes filtration (vacuum disc
   filter)                      1,150     1,150

Tailings dewatering bed          —       	       2 120     2 120

Evaporators                     1,470    1,1470
ii»ajju{-c»i/j.oii pona
Asphalt fixation
Cement fixation
TOTAL
___
	
1,210
$4.750
--—
M.UOO
	
^$7,900
2,300
	
1,210
$6.550
2,300
MOO
	
$9.700
(a)NRC-DGEIS (NR 79),  Table 11.9.
                                    B-15

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                                 TABLE B-3



                                                          (a)
                 Annual  Operating  Costs  for  Matrix  Fixation'



                        (thousands of 1978 dollars)
Costs
Salaries
Maintenance
Power
Fuel
Asphalt
Cement
TOTAL (annual)
Thermal Evaporator
Cement Asphalt
$ 170
110
75
4,250

1,970
$6,575
$ 170
170
75
14,7^0
3,360
...
$8,515
Filter Bed
Cement
$ 85
50
35
—
	
1,970
$2,1 HO
Asphalt
$ 85
100
35
490
3,360
—
$4 , 070
(a)NRC-DGEIS (NR 79),  Table 11.10.
                                    B-16

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fixation, initial capital costs are somewhat less expensive for



mechanically drying the tailings with a thermal evaporator than with a



"dewatering filter bed" (a sand filter).  Significant savings in annual



operating expenditures can be gained, however, by using the "dewatering



filter bed" rather than the thermal evaporator.  That is, annual



operating costs are at least a factor of two less than those for a



thermal evaporator for both cement and asphalt matrix fixation.







B.2.7  Tailings Transportation




     We considered three methods of hauling uranium mill tailings:



truck, rail, and slurry pipeline.  According to Ford, Bacon and Davis,



Utah, Inc. (FB 76-78), contract haulers can transport mill tailings at a



cost of $0.10/ton-mile.  For longer distances of 50 miles or more, rail



transport, at $0.08/ton-mile, offers some cost advantages over trucking.



Unless the tailings pile is located at a rail head, however, the tailings



will have to be hauled to the rail line by truck.








     Transporting uranium mill tailings by pipeline offers greatly



reduced operating expenditures as compared to either truck or rail, but



requires heavy initial capital and right-of-way costs.  According to



Dames and Moore (DA 77),  a pipeline 7" in diameter costs $63,8HO/mile to



construct and to reserve the right-of-way.  Transporting mill tailings



via such a pipeline is estimated to cost $O.OM8/ton-mile.
                                    B-17

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B.2.8  Discount Rate

     The discount rate is assumed to be 7%.  This is the estimated

average real rate of return considering all elements of society (NR 76).

The real rate of return is the current rate of return minus the inflation

rate.  The discount rate is used for computing the present discounted

value of future costs (to maintain and replace fences in the future, for

example).



B.2.9  Present Worth of Future Costs

     Several control methods may require perpetual care or periodic

replacement in order to maintain the intended level of effectiveness.

For example, we assumed that chemical  stabilization needs replacement

every four years.  Fences are assumed  to require  annual maintenance, and

replacement every hundred years.  Finally, natural precipitation may need

to be supplemented with irrigation to  maintain a  proper vegetation  cover

for surface stabilization.  The irrigation system is assumed to require

annual maintenance, and periodic replacement.



     The present worth of all future costs are included in the cost

breakdown shown in  the tables where appropriate.  The  formula used  for

Present worth calculations  is:
where:     PW • present  worth,
            C = replacement  cost of the item considered,  or
                its  periodic maintenance cost,
            n = the  useful life of the item, or the
                periodic maintenance period,
            i » the  annual discount rate.
                                       B-18

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This formula assumes that maintenance and replacement continues



indefinitely.  The annual discount rate used in all calculations is !%•







B.2.10  Land Costs



     Smith and Lambert (SM 78) estimate that farmland costs an average of



$781 per hectare, and may range between $160 and $5,189 per hectare.







B-3  Cost Estimates For Disposal Options




     Using the estimated unit costs (from Table B-1) and assuming the



dimensions of the average inactive uranium mill tailings pile, we have



estimated costs for the tasks necessary to complete various disposal



options.  When considered as various combinations of the tasks, the



estimated costs offer numerous control options.  In actual practice, the



choice of a specific disposal option and actual control cost will depend



on such site-specific parameters as the radon emission rate, size, and



condition of the specific mill tailings pile.







B.3.1  Option 1 - No Radon Control



     This option may be implemented either by constructing a fence around



the existing disposal site (thereby restricting access) or by stabilizing



the existing mill tailings pile to reduce future wind and water erosion.







B.3.1.1  Option 1a - Fencing




     In this disposal option, the uranium mill tailings pile is left at



its existing surface location and a fence is erected around the site.  No
                                     B-19

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control of radon-222 releases, particulate releases, or ground water
impacts is provided, although fencing provides some control of direct
gamma radiation by preventing people from living near the tailings pile.
It is assumed that wind erosion can cause particulates to migrate as far
as 1000m from the pile.  Therefore, it is assumed that a 1000m
exclusionary zone is required on all sides of the tailings pile.

     The cost of a fence can be expected to range between $290,000 for a
chain-link fence five  to six feet  high and $820,000 for a security fence
of prison grade.  The  present worth of annual maintenance and replacement
every hundred years  is estimated to be $40,000 for  a chain link  fence and
$120,000 for a security fence.

     In either case, the fence encloses  593-4 hectares  of land.  The
tailings pile is assumed to be on  a 19-hectare site that is  already
publicly owned.  It  is assumed that the  remaining 511.1 hectares must be
purchased, at a cost of $130,000.  The 19  hectares  already under public
ownership represent  a  cost  to  society, since  they are  unavailable  for
alternative uses.   The best alternative  use  is assumed  to be
agricultural.  The  "opportunity  cost," or  market value, of the  land  is  an
estimated $10,000.   In total,  the  cost of the "no control" option  is
*790,000  if a chain-link fence  five  to  six feet  high  is used, and  $2.1
million  if a security  fence is employed.
                                     B-20

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B.3-1.2  Option 1b - Stabilization With No Radon Control



     The mill tailings pile is left in place in this disposal option but



stabilized to prevent wind and water erosion.  Several of the existing



inactive tailings piles have already been stabilized with about six inches



of soil cover, vegetation, gravel, or riprap.  The equivalent of 0.5m of




riprap cover is required to ensure longevity.  A 15cm to 0.5m dike cover



would meet short-term requirements, but vould be subject to both wind and




water erosion and thus subsequent degradation.  Riprap cover has been




utilized at one pile and experience with stabilization of large tailings




piles is quite limited.  This level of control might be accomplished



through the use of chemical sprays, which either form a surface crust or




bind the surface  tailings into a  crust.  Experience with such methods,




however, indicates that the resulting crusts are not resistant to



environmental degradation (Tuba City and Salt Lake City (FB 76)).  The



degradation results  from intrusion by man and animals, ultraviolet




radiation, and various climatological effects.  Chemical sprays and



binders appear to require a protective  layer of dirt or riprap to assure




even a  relatively short  lifetime  of  10  years.  Thus,  they have a limited



applicability  for this level  of control.








     The  sides of the  tailings pile must  be shaped  to  a slope  ratio  of




8:1  to minimize  future erosion and a  20m  exclusionary  zone  should  be




provided  around  the  pile.   Besides a  chain-link  fence  and a security




fence,  several stabilization  methods  are  considered  here.   Vegetation




could  be  employed,  but may  require the purchase  of  suitable top  soil or
                                     B-21

-------
an irrigation system.  Potentially, riprap and gravel could provide



long-term wind and water erosion protection.  Finally, chemical



stabilizers provide erosion protection but are expected to need




replacement every four years.







     Table B-4 presents the cost and dimension estimates for the



alternative methods that will control particulates at the model uranium




mill tailings pile.







     At a minimum, the total cost  of providing wind  and water  erosion



protection for the model mill tailings pile will  be  $500,000.  This



includes:  enough earthwork to  change the  embankment slopes  from 2:1 to



8:1, stabilization by vegetation that requires neither soil  purchase or



irrigation, and  a chain-link fence five  to six feet  high.  On  the  other



hand, the level  of control could cost as much as  $3-6 million  if the



model pile roust  be stabilized by riprap  and isolated by a  security fence,
                                     B-22

-------
                                 TABLE B-4

                Costs and Dimensions of Participate Control
Volume of earth work (m3)                                     135 000
Area of cover (ra2)                                            2*47*000
Length of fence (m)                                             2*140
Area within fence (ra2)                                        287*000
------------------ Costs (in thousands of 1978 dollars) ---- ~ ___ - ______

Earth work                                                        200

Stabilization
  Veg:  With no need to
       purchase soil                                              18Q
    With purchase of soil                                         620
  Irrigation
    (labor & equip.)                                               H0
  Riprap                                                        ^ 1flo
         ,
  Chemical
Fencing
  Chain-link, five to six feet high                                60
  Security (prison grade)
Future Costs
  Irrigation
    (labor & equip.)                                               110
  Chemical stabilization                                           cqo
  Chain- link fence                                                  w
  Security fence                                                    50

Value of Land                                                       20
                                     B-23

-------
B.3.2  Controlling Radon Emissions with an Overburden



     As noted in the NRC-DGEIS  (NR 79), radon emanation  can be reduced  by




appropriately thick overburden.  The overburden may be a layer of soil  or



a combination of soil and a cap consisting of asphalt, clay, or synthetic



material.  For Option 2 (Existing Surface Site, Covered to Control Radon)




and Option 3 (New Site, Below Grade, with Liner if Needed), seven types



of overburden are considered for dimension and cost estimation.  The



required thickness of overburden needed to provide the five selected




radon attenuation levels for each type of overburden are presented in




Table B-5.








B.3.3.  Option 2 - Existing Surface Site.




        Covered to Control Radon Emissions



     This disposal option consits of covering the tailings pile at the




existing surface site for control of radon-222 releases.  In addition,




this control option reduces wind and water erosion of the mill tailings,



attenuates gamma radiation, and provides some control of ground water



contamination.  Basically, this option requires three steps:  covering



the mill tailings, stabilizing the pile against wind and water erosion,



and fencing the disposal area to prevent intrusion.  There are several




ways to accomplish each steps.  This leads to numerous possible



combinations of methods to implement this disposal option.  The steps and




their alternative methods are given in Table B-6.

-------
                                 TABLE B-5


   Thickness (meters)  of Cover Required to Reduce Radon to Control Level


                                                        2
                              Radon Control Level (pCi/rc /sec)


                               100     10     5     2     0,5


Soil(a)                        1.1    2.9   3.4   U.1     5.1


Soil + 0.6 m Clay(b)           o.3    0.9   1.M   2.1     3.2


Soil + 1.0 m Clay(c)           0.3    0.7   0.8   1.0     1.9


Soil + Asphalt(d)               ..    __    ..    ._      0.5


Soil + Synthetic(d)             __    __    __    __      0.5
    	  with average radon-attenuating properties.
(b)Thickness includes both clay and soil.  If thickness is 0.6m or less
     then includes clay only.

(c)Thickness includes both clay and soil.  If thickness is 1.0m or less
     then includes clay only.

(d)Asphalt and synthetic caps are assumed to reduce radon to at least
     1.0 pCi/m2 sec.  Thickness only includes soil.  The dashes (—)
     mean no soil is required.


Source:  NHC-DGEIS, Table K-6.1, p.K-27. (Ref. NR 79)
                                     B-25

-------
                                 TABLE B-6

                   Control Methods for Disposal Option 2
             (Existing Surface Site,  Covered to Control Radon)
1 •  Cover
     a. Soil (normal radon-attenuation properties)
     b. Soil + 0.6m clay (no clay purchase required)
     c. Soil + 0.6m clay (clay purchase required)
     d. Soil + 1.0m clay (no clay purchase required)
     e. Soil + 1.0m clay (clay purchase required)
     f. Soil + asphalt
     g. Soil + synthetic


2.  Stabilization

     a. Vegetation (no soil or loam purchase required)
     b. Vegetation (soil or loam purchase required)
     c. Irrigation required (a or b)
     d. Irrigation not required (a or b)
     e. Riprap
     f. Gravel
     P. Chemical


3.  Fence

     a. Chain-link fence five to six feet high
     b. Security fence (prison grade)
                                    B-26

-------
B.3.3.1  Dimensions







     All dimensions assume that the existing uranium mill tailings piles



and the resultant 'disposal mounds are in the shape of truncated regular



pyramids.  By assumption, the sides of the final disposal mound have a



slope ratio of 8:1 in order to resist future wind and water erosion.



Also, an exclusionary zone of 20m from the base of the final disposal



mound is assumed.  Finally, the dimensions and conditions of the average



inactive uranium mill tailings pile are those described  in Section B.1.







B.3.3.2  Cost Estimates



     Cost estimates based on the dimensions  of the average inactive



uranium mill tailings pile are presented for each of  five selected radon



attenuation levels in Tables B-7 through B-11.  Cost  estimates  for



various tasks necessary  to implement Option  2 are found  in these tables.



Note that the total cost of implementing Option 2 will vary with such



things as the desired radon attenuation level, the selected type of



overburden, the  method  of stabilization, and the  fencing.








     Several points concerning the  derivation of  the  cost  estimates  need



some explanation:








      1.  The volume of  earth  work,  specific to  a  type of cover, does not



include the volume of the cap.   With clay  caps,  for  example,  the  volume



of the cap  is  not included in the  volume  of the earth work.
                                      B-27

-------
                                 TABLE B-7
                     Costs and Dimensions for Disposal

                                                        2
             Option 2 with Control of Radon to 100 pCi/m /sec

Depth of cover (m)
Volume of cover (m3)
Area of cover (m2)
Length of fence (m)
Area within fence (m2)
f t
	 Costs (in
Earth work
Cap
Clay
With clay available
With clay purchase
Other
Asphalt
Synthetic
Stabilization
Veg: NO need to
purchase soil
With purchase of soil
Irrigation
(labor & equip.)
Riprap
Gravel
Chemical
Fencing
Chain link, five to six
feet high
Security (prison grade)
Future Costs
Irrigation
(labor & equip.)
Chemical stabilization
Chain-link fence
8ftf«iv4 *w £*nr*a
Soil
1.1
415,000
264,000
2,210
306,000

thousands of
$ 630

-

—
"

200
660

40
3,410
680
200

70
190

120
630
10
30
Soil +
.6m Clay
.3
209,000
251,000
2,160
292,000
.
1 Q TSt ft /\1 1 0 V* B 1 •
iy/O QOLLaL&J
$ 240

110
260

™*


190
630
i t\
40
3,240
650
190

60
180

110
600
10
30
Soil +
1m Clay
.3
209,000
251,000
2,160
292,000


$ 240

110
260




190
630

3,240
650
* A/\
190

60
180

110
600
10
30
Soil +
Other
-
•»
«•

•••••••••»••»•••••


-

-

I


-
_
-


••

-
Value of land
20
20
                                                          20
                                     B-28

-------
                                TABLE B-8

                    Costs and Dimensions for Disposal


Depth of cover (m)
Volume of cover (m3)
Aera of cover (m2)
Length of fence (m)
Area within fence (m2)

Soil
2.9
917,000
295,000
2,330
339,000

Soil +
.6m Clay
.9
363,000
261,000
2,200
303,000

Soil +
1m Clay
.7
311,000
258,000
2,190
299,000

+
Other_
-
••
••
—

	.	Costs (in thousands of 1978 dollars)	

Earthwork                  $1,380        $390        $290

Cap
  Clay
    With clay available          -          210          250
    With purchase of clay        -          520          610
  Other
    Asphalt                      -
    Synthetic                    -

Stabilization
  Veg:  No need to
       purchase soil            220          200           190
    With purchase of soil       740          660           650
  Irrigation
     (labor & equip.)             40            40            40
  Riprap                      3,810         3,370         3,330
  Gravel                        760          670           660
  Chemical                      220          190           190

Fencing
  Chain link                    70            70            70
  Security  (prison grade)       200           190           190

 Future Costs
   Irrigation
     (labor  & equip.)           130          120          120
   Chemical  stabilization       700          620          610
   Chain-link fence              10           10           10
   Security fence                30           30           30

 Value of Land                   30           20           20


                                      B-29

-------
                                 TABLE B-9




                     Costs  and Dimensions for Disposal
-* • -


Depth of cover (m)
Volume of cover (m3) 1
Area of cover (m2)
Length of fence (m)
Area within fence (m2)
_ / •
	 Cost (in
Earth Work
Cap
Clay
With clay available
With clay purchase
Other
Asphalt
Synthetic
Stabilization
Veg: No need to
purchase soil
With purchase of soil
Irrigation
(labor & equip.)
Riprap
Gravel
Chemical
Fencing
Chain link
Security (prison grade)
Future Costs
Irrigation
(labor & equip.)
Chemical stablization
Chain- link fence
QAS«««W« ^« £A-V*J*A


Soil
3.4
,066,000
304,000
2,360
349,000

thousands
$1,610

—

•


230
760
40
3,920
780
220
70
200

140
720
1 A
1U
30

Soil +
,6m Clay
1.4
495,000
269,000
2,230
312,000
_r i mQ «i«O 1 a*-a ^—
or J.7/O dollars/
$ 590

210
520




200
680
40
3,480
690
200
70
190

120
640
10
A v
30

+ .
1m Clay
.8
337,000
260,000
2,200
301,000


$ 300

290
690




190
650
40
3,350
670
190
70
190

120
620
10
30

Soil +
Other
-
•*•
•^^•^•M^-W


—

—

_m


—
• »
-

-
-
Value of Land



                                     B-30
30           20           20

-------
                                TABLE B-10

                     Costs  and Dimensions for Disposal
                                                      2
             Option 2 with  Control  of Radon to 2 pCi/m /sec


Depth of cover (m)
Volume of cover (m3)
Area of cover (m2)
Length of fence (m)
Area within fence (m2)

Soil
4.1
1,283,000
317,000
2,410
362,000

Soil +
.6m Clay
2.1
687,000
281,000
2,280
324,000

Soil + Soil +
1m Clay Other
1.0
389.000
263,000
2,210
305,000
	Costs (in thousands of 1978 dollars)	

Earth Work                  $1,940        $ 880        $ 330

Cap
  Clay
    With clay available          -          210          360
    With clay purchase           -          520          870
  Other
    Asphalt                      -
    Synthetic                    -

Stabilization
  Veg:  No need to
      purchase soil            240          210          200
    With purchase of soil      790          710          660
  Irrigation
    (labor & equip.)            40           40           40
  Riprap                     4,080        3,630        3,390
  Gravel                       810          720          680
  Chemical                     230          210          190

Fencing
  Chain link                    70           70           70
  Security (prison grade)      200          190          190

Future Costs
  Irrigation
    (labor & equip.)           140          130          120
  Chemical stabilization       750          670          630
  Chain-link fence              10           10           10
  Security fence                30           30           30

Value of Land                   30           20           20


                                     B-31

-------
                                  TABLE B-ll


                      Costs and Dimensions  for Disposal
                                                        2
             Option 2 with Control of Radon to 0.5 pCi/m /sec



Depth' of cover (m)
Volume of cover (m3) 1,
Area of cover (m2)
Length of fence (m)
Area within fence (m2)


Earth Work
Cap
Clay
With clay available
With clay purchase
Other
Asphalt
Synthetic
Stabilization
Veg: No need to
purchase soil
With purchase of soil
Irrigation
(labor & equip.)
Riprap
Gravel
Chemical
Fencing
Chain link
Security (prison grade)
Future Costs
Irrigation
(labor & equip.)
Chemical stabilization
Chain- link fence
Security fence

Soil
5.1
607,000
335,000
2,470
381,000
Soil +
.6m Clay
3.2
1,006,000
300,000
2,350
345,000
(in thousands of 1978
$2,430


-
-

-
••


250
840

50
4,320
860
250

70
210


150
800
10
30
$1,360


210
520

-
™


230
750

40
3,880
770
220

70
200


130
720
10
30
Soil +
1m Clay
1.9
631,000
278,000
2,270
321,000


$ 690


360
870

-
"


210
700

40
3,590
710
200

70
190


120
660
10
30
Soil +
Other
.5
260,000
255,000
2,180
296,000


$ 390


—
mm

300
760


190
640

40
3,290
650
190

60
180


110
610
10
30
Value of Land                   30           30           30            20



                                     B-32

-------
     2.   Earth work includes excavating,  loading,  hauling up to one mile,



spreading, and compacting surface soil.







     3.  Caps are assumed to cover both the tailings and the crest of the




impoundment dikes.







     U.  Asphalt and synthetic caps are expected to reduce  radon releases



to 1.0 pCi/m2/sec without additional soil cover.  As a result, cost



estimates  for covers involving asphalt or synthetic caps have  been



computed  only for  radon  control  levels of  1.0  pCi/m2/sec and below.







      5.   Several  control methods in Table  B-6  require  periodic mainten-



ance and  replacement  of  equipment (e.g., irrigation equipment, chemical



 stabilizers,  and  fences).   The  discounted  present  value  of these future



 costs have been computed in each case.








      6.   After control measures are  completed, the use of land within the




 fences will presumably be restricted.   Alternative uses, such as



 agricultural, therefore  will be permanently denied.  This opportunity cost



 should be considered in the decision-making process along with the other



 costs.  For this purpose, the restricted land is assumed to have



 agricultural uses, and  the opportunity cost is equal to the market value



 of the property.
                                      B-33

-------
B.3.3.3  Use of Tables B-7 Through B-11
     Since Tables B-7 through B-11 present only the costs of accomplishing
particular tasks that might be employed in a control option, it is
important for the reader to understand the proper use of these tables for
deriving the total cost for a desired control option.

     After selecting the desired radon attenuation level and type of/
overburden (i.e., reading down one column of the selected table) one can
calculate a total cost for the selected control option.d)  The total
cost is then equal to the sum of the cost of the required overburden
(earth work plus cap costs), the cost of the specific method of
stabilization (plus the cost of irrigation if required), the cost of the
desired fence, the necessary future costs, and the market value of the
land.  For example, the total cost of attenuating to a radon flux equal
to 5 PCi/m2/seo  (refer to Table B-9) is $1.2 million, if soil plus a
1.0ro clay cap is used as an overburden (assuming a suitable clay is
locally available at no cost). We assumed that the site is stabilized
with vegetation  requiring both the purchase of top soil and irrigation
equipment, and that a chain-link fence five to six feet high is required.
the asphalt or  synthetic caps differ
                                     B-31*

-------
 B'3*1*   Option  3  -  New Site.  Below Grade, with  Liner  if Needed
     The  objective of Option 3  is not  only  to  reduce radon  emission and
 gamma  radiation, but  also  to provide greater hydrologic control  than
 Option 2  would afford.

 B.3.4.1   Requirements
     In addition to the three steps necessary  to  implement  Option 2, this
 option requires excavating a special pit, installing a liner (if neces-
 sary), and transporting the  tailings to the pit site.   The  need  for a
 liner  depends on the  subsoil characteristics at the  new site.  If the
 subsoil is relatively impervious  to moisture seepage (e.g., clay with a
 high montmorillonite  content, or  impervious shale),  then a  special  liner
may not be required.  Also, a pit above the water table may obviate the
 need for a liner.  For this option, transporting the tailings includes
 excavating the tailings from their present site, hauling them to the new
 site, and depositing  the mill tailings in the pit.

     Like Option 2, there are several ways of accomplishing each step of
this option.  Table B-12 presents each step and alternatives.
Considering each possible combination presented in Table B-12 leads to
numerous methods of implementing this disposal option.
                                    B-35

-------
                          TABLE B-12

             Control Methods for Disposal Option 3
         (New Site, Below Grade,  with Liner if Needed)
 1.  Tailings Transportation
    a.  Truck
    b.  Truck and rail
    c.  Pipeline

 2.  Below-Grade Excavation
    a.  Normal
    b.  Shale (ripping necessary)

 3.  Liner
    a.  Clay (with clay available)
    b.  Clay (clay purchase required)
    c.  Asphalt
    d.  Synthetic
    e.  None

4.  Cover
    a.  Soil (normal radon-attenuation properties)
    b.  Soil + 0.6m clay (with clay available)
    c.  Soil + 0.6m clay (clay purchase required)
    d.  Soil + 1.0m clay (with clay available)
    e.  Soil + 1.0m clay (clay purchase required)
    f.  Soil + asphalt
    g.   Soil + synthetic

5«  Stabilization
    a.   Vegetation (no soil or loam purchase required)
    b.   Vegetation (soil or loam purchase required)
    c.   Irrigation required (a or b)
    d.   Irrigation not required (a or b)
    e   Riprap
    f.   Gravel
    g.   Chemical

6»  Fence
    a.   Chain-link fence five to six feet high
    b.   Security fence (prison grade)
                               B-36

-------
 B.3.^.2  Dimensions and Cost Estimates
      For each of five selected radon attentuation levels, we calculated
 dimensions and costs for the various control methods for implementing
 Option 3 (Table B-12).  The distance to the new disposal site and the
 geometric configuration of the pit are assumed constant in this analysis.
 Several of the dimensions (and,  therefore,  the costs) also remain constant
 regardless of the  depth and type of overburden placed over the mill
 tailings,  while other dimensions (and costs) vary.   These constant costs
 are  given in  Table B-13.


      As previously noted,  there  are 78U,OOOm3 of uranium mill tailings
 (weighing  1,325,000 short  tons)  to be excavated  by  dragline and hauled to
 the  pit site.   The area  to be  stabilized  is  1?6,000m2 (the pit,
 regardless  of  depth,  is assumed  to a  square  K2Qm  on  a side).   Similarly,
 1,8UOra  of  fencing  will  be  required to enclose 212,000m2 of land
 (including  both  trie pit and the  exclusionary zone which is 20m  on  each
 side).   The excavated  pit  is assumed  to be in the shape of a  truncated
 inverted regular pyramid whose sides  are required to  have a slope.ratio
 of 3:1.


     We assumed  that  the pit site  is  located  10 miles from  the  inactive
mill tailings site.  Rail  heads are assumed  to be situated  one  mile from
both the inactive  tailings site and the pit  site.  It is  assumed that  the
land for the pit and its exclusion zone will  be purchased at  the market
                                     B-37

-------
                               TABLE B- 13

    Constant Costs for Below-Grade Disposal of Uranium Mill Tailings


                                          In thousands of 1978 dollars

Excavate, load, spread, and compact tailings             $1,500

Tailings Transportation
  Truck                                                   1,300
  Truck and rail                                          1»100
  Pipline                                                 1»280

Stabilization
  Veg:  No soil purchase                                   130
        With soil purchase                                 W°
  Irrigation
    (labor and equip.)                                      30
  Riprap                                                 2»280
  Gravel
  Chemical
Fencing
  Chain link                                                5°
  Security (prison grade)                                  1^°

Land Cost                                                   20

Future costs
  Irrigation (labor and equip.)                            10°
  Chemical stabilization                                   509
  Chain-link fence                                          ™
  Security fence                                            20
                                    B-38

-------
value of farmland.  For this disposal option "earth work" means
below-grade excavation, hauling up to one mile, dumping, spreading, and
compacting subsoil, and disposing of any excavated subsoil not used in the
cover.  The costs that vary by radon control level are given in Tables
B-11) through B-18 for each selected level.

B.l»  Other Disposal Methods
     There are several high-cost alternatives to the disposal methods
previously considered.  These methods are discussed in the NRC-DGEIS
(NR 79).  Two of these methods are considered here: burial in a strip-
mine or underground mine, and nitric acid leching for the removal of
hazardous materials.  Potentially, these alternatives offer considerable
radon attenuation (below 0.5 pCi/m2/sec), but the long-term
environmental impact of these methods has not been tested.

B'1*'1  Extraction and Disposal of Hazardous Materials
     Technology has not been developed for extracting radium or
nonradiological toxic elements from the tailings, because until now there
has been no need for this method

     A nitric acid leaching plant could be set up to remove the radium and
thorium in the tailings.  Tailings from this process would still require
some treatment, though the radioactivity level would be considerably
lower.  Some hazardous nonradiological elements would remain.  Seepage
from the new pile would contain nitrates instead of the sulfates found in
                                     B-39

-------
                                TABLE B-14

                Variable Costs and Dimensions for Disposal
                                                        p
             Option 3 with  Control of Radon to 100 pCi/m /sec


Depth of cover (m)
Vol. of pit
With clay liner (m3)
No clay liner (m3)
Vol. of clay liner (m3)
Area for other liner (ra2)
Vol. of clay cap (m3)
Area for other cap (m2)
Soil
1.1

1,145,000
975,000
170,000
172,000
—
—
Soil +
,6m Clay
.3

1,014,000
837,000
177,000
176,000
53,000
— '
Soil + Soil +
Ira Clay Other
.3

1,014,000
837,000
177,000
176,000
53 , 000
"
                      -Costs (in thousands of 1978 dollars)-
Earth work
  No clay liner
    Normal digging           $2,890        $2,480        $2,480
    Shale                     4,320         3,710         3,710
  Clay liner                                                nnn
    Normal digging            3,390         3,000         3,000
    Shale                     5,100         4,490         4,490

Liner

  C1Clay available              350           370           370
    With clay purchase          850           890           890
  Other
    Asphalt                     300           310           310
    Synthetic                   760           780           780

Cap

    With clay available          -
    With clay purchase           -
  Other
    Asphalt
    Synthetic                    "
                                    B-40

-------
                                TABLE B-15

                Variable Costs and Dimensions for Disposal

             Option 3 with  Control  of Radon to 10 pCi/tn2/sec


Depth of cover (m)
Vol. of pit
With clay liner (m3)
No clay liner (m3)
Vol. of clay liner (m3)
Area for other liner (m2)
Vol. of clay cap (m3)
Area for other cap (m2)
Soil
2.9

1,436,000
1,275,000
162,000
163,000
—
—
Soil +
.6m Clay
.9

1 , 1 1 1 , 000
941,000
170,000
173,000
104,000
-
Soil + Soil +
1tn Clay Other
.7

1,078,000
906,000
172,000
174,000
122,000
— —
                       •Costs (in thousands of 1978 dollars)-
Earth work
  No clay liner
    Normal digging           $3,770        $2,790        $2,680
    Shale                     5,650         4,170         4,020
  Clay liner
    Normal digging            4,250         3,290         3,190
    Shale                     6,360         4,920         4,780

Liner
  Clay
    With clay available         330           350           360
    With clay purchase          810           850           860
  Other
    Asphalt                     290           300           310
    Synthetic                   720           770           770

Cap
  Clay
    With clay available          -            220            250
    With clay purchase           -            520            610
  Other
    Asphalt                      -
    Synthetic                    -              -
                                     B-41

-------
                                 TABLE  B-16

                 Variable  Costs  and  Dimensions  for Disposal


Depth of cover (m)
Vol. of pit
With clay liner (ra3)
With no liner (m3)
Vol. of clay liner (m3)
Area for other liner (ra2)
Vol. of clay cap (ra3)
Area for other cap (ra2)
Soil
3.4

1,514,000
1,355,000.
158,000
161,000
-
•
Soil +
.6m Clay
1.4

1,195,000
1,026,000
168,000
171,000
103,000
™*
Soil +
1m Clay
.8

1,095,000
924,000
172,000
174,000
140,000

Soil +
Othei
• _ -

-
-
-
—
-

                       -Costs (in thousands of 1978 dollars)-
Earth work
  No clay liner
Liner
    With clay available         330           350           360
    With clay purchase          790           840           860

                                                            73;°
                                                            770
    Synthetic                   710
Cap
    With clay available          -           210           290
    With clay purchase         .  -           DIU
  Other
    Asphalt                      "'
    Synthetic
                                    B-42

-------
                             TABLE B-17


             Variable Costs and Dimensions for Disposal

                                                    p
           Option 3 with Control  of Radon  to  2  pCi/m /seo



Depth of cover (m)
Vol. of pit
With clay liner (m3)
No clay liner (m3)
Vol. of clay liner (m3)
Area for other liner (m2)
Vol. of clay cap (m3)
Area for other cap (m2)

Soil
4.1

1,621,000
1,468,000
155,000
158,000
-
-
Soil +
.6m Clay
2.1

1,308,000
1,144,000
165,000
167,000
100,000
Mi
________________________Pna^n (in thmi«anrt« of* 1Q7R
Earth work
No clay liner
Normal digging
Shale
Clay liner
Normal digging
Shale
Liner
Clay
With clay available
With clay purchase
Other
Asphalt
Synthetic
Cap
Clay
With clay available
With clay purchase

$4,340
6,490

4,800
7,180


320
780

280
700


-
-

$3,390
5,070

3,870
5,800


340
820

290
740


210
500
Soil +
1m Clay
1.0

1,128,000
958,000
170,000
173,000
174,000
-



$2,840
4,240

3,340
5,000


350
850

300
760


360
870
Soil +
Other
_

-
-
-
-
-
~



-
-

-
-


_
-

—
-


—
-
Other
  Asphalt
  Synthetic

-------
                            TABLE B-18
            Variable Costs and Dimensions for Disposal

                                                    2
         Option 3 with Control of Radon to 0.5 pCi/m /sec
Soil + Soil +

Depth of cover (m)
Vol. of pit
With clay liner (m3) 1
No clay liner (m3) 1
Vol. of clay liner (m3)
Area for other liner (m2)
Vol. of clay cap (m3)
Area of other cap (m2)

Earth work
No clay liner
Normal digging
Shale
Clay liner
Normal digging
Shale
Liner
Clay
With clay available
With clay purchase
Other
Asphalt
Synthetic
Cap
Clay
«f
With clay available
With clay purchase
Other
Asphalt
Soil
5.1

,771,000
,620,000
151,000
153,000
_
-
/ •! M tVl/\1YQ9'
V In T*nOU3cl
$4,800
7,180
5,240
7, .850

310
760

270
670


_

^
.6m Clay 1m
3.2 1

1,482,000 1,277
1,323,000 1,110
159,000 166
162,000 168
97,000 169
—
nrt«» nf 1Q78 dollars)
IIUO UA ' 7 ' V* W A. * W4 U /
$3,920
5,860
4,390
6,570

330
760

290
710


200
490

~ .
Clay
.9

,000
,000
,000
,000
,000
—


$3,290
4,920
3,780
5,660

340
830

300
740


350
850

_
Soil +
Other
.5

1,045,000
872,000
173,000
175,000
-
174,000


$2,580
3,860
3,090
4,630

360
870

310
780


-
310
770
Synthetic
                                B-44

-------
a conventional mill tailings.  Nitrates are quite mobile if seepage



reaches ground water.  The cost of chemical treatment of tailings is as




yet undetermined, but could be expected to be as expensive as the original




milling process, excluding ore grinding.  Since this technique is expected



to be only about 90$ effective, some action would still be required to




isolate the tailings from the biosphere and to dispose of the extracted



material in a licensed waste burial site.








     Uranium mill tailings disposal by a nitric acid leaching process




requires construction and operation of a nitric acid leaching mill,



disposal of the concentrated nitric acid leachate, and disposal of the




residual tailings.  The construction and operation of a nitric acid




leaching mill is quite expensive.  The NRC-DGEIS (NR 79) estimates that a



model nitric acid leaching mill costs $35 million to construct and an




additional $37.7 million to equip (1978 dollars), while operating costs




are expected to run $12.50 per ton of processed uranium mill tailings.








     Assuming that the model inactive mill pile contains 1.32 million




short tons of tailings and that a model nitric acid leaching mill can




process 1,984 short tons of mill tailings and produce 55 short tons of



nitric acid leachate per day, then 668 days of operation would be required



to process the mill tailings.  In .addition, approximately 37,000 short



tons of nitric acid leachate will be generated.  Consequently, the total




operating cost for a model nitric acid leaching mill at the model inactive



mill tailings pile is expected to run $16.6 million.  Some of the




construction materials used in a model nitric acid leaching mill might be

-------
employed at more than one inactive mill tailings site, or might  have.some



scrap value.  These possibilities are not analyzed  here, due  to  the



uncertainties of apportioning construction costs and determining future




scrap values.  We therefore assume that each inactive mill tiilings site



requires building a new nitric acid leaching mill at a cost of $35



million.  On the other hand, we assume that the nitric acid leaching




equipment can be used at more than one inactive mill tailings site.  As a



result, cost of the nitric acid leaching equipment  is equal to its



depreciated value.  Assuming two years of use at the model inactive mill




tailings site, a 15-year life expectancy for the nitric acid  leaching



equipment, and straight-line depreciation, the expected cost  of  the nitric



acid leaching equipment is $5 million at each model inactive  mill tailings



site.  An additional $5 million is added to cover the costs of transport-



ation between different mill tailings sites, set-up and take-down costs,




and extra wear and tear on the equipment, as well as other contingencies.




We therefore exp.ect the total nitric acid leaching  equipment  costs to be



$10 million.  In total, we expect nitric acid leaching to cost $61.6



million (1978 dollars) to construct, equip, and operate the model inactive




mill tailings site.








     When combined in an asphalt or cement matrix, the nitric acid



leachate matrix has a volume of 17,100m3 and requires a cover 10m thick.



for proper disposal.  The disposal of the nitric acid leachate would




require a pit 13.% deep and covering an area of .5 hectares (100m by



50m).  The possible costs of disposing of the nitric acid leachate are




Presented in Table B-19.

-------
                                 TABLE B-19

                   Costs  of Nitric Acid Leachate Disposal
                         (thousands of  1978 dollars)
          Task                                             Cost

     Earth work
          Normal digging                                   $200
          Shale                                             300

     Fixation
          Asphalt                                           560
          Cement                                            380

     Stabilization
          Vegetation
             No need to purchase soil                         14
             With soil  purchase                              30
             Irrigation                                       2
          Riprap                                             60
          Gravel                                             10
          Chemical                                            4

     Fencing(a)
          Chain link                                         !0
          Security (prison grade) fence                      40

     Future costs
          Irrigation                                         10
          Chemical stabilization                             30
          Chain link fence                                    2
          Security (prison grade) fence                      10

     Value of land                                            1


^)Includes a 20m isolation zone around the disposal pit.

-------
     The NRC-DGEIS (NR 79) estimates that the concentration of radium



remaining in the residual tailings after nitric acid leaching is at least



an order of magnitude greater than background levels.  If soil with



average radon attenuation properties is available in the area, a



3.8m=thick cover will provide attenuation to 0.1 pCi/m2=sec.  Assuming



that the nitric acid leaching process insignificantly alters the quantity



of residual tailings, and using the assumptions employed for Option 3



(Section B.3.4 — New Site, Below Grade, with Liner if Needed), then the



disposal costs for the residual tailings can be computed.  The costs of



disposing of the residual tailings are presented in Table B-20.








     In summary, nitric acid leaching of the tailings for the model



inactive mill site will cost $61.6 million.  Under the best conditions,



disposal of the nitric acid leachate can be expected to cost an additional



$600,000 (normal soil excavation, stabilization with vegetation—no



irrigation required—and isolation with a chain-link fence).  Under the



worst conditions, disposing of the nitric acid leachate will cost



*970,000 (shale excavation, riprap stabilization and security fence



isolation).  Disposal costs for the residual tailings will be $7 million



at best—that is, if no liner is required; excavation is in normal soil;



tailings are transported by truck and rail; vegetation requiring no



irrigation is used to stabilize the disposal site; and the disposal site



is isolated with a chain-link fence.  On the other hand, the costs of



disposing of the residual tailings could be as high as $13.1 million if a



clay liner is used and the clay must be purchased; pit excavation is in



shale, trucks are the only transportation available for the tailings; and




the disposal site is stabilized by riprap and isolated bv a security



                                    B-48

-------
                           "  1LE B-20

               Costs of Residual Tailings Disposal
                   (thousands of 1978 dollars)
     Task                                             Cost

Earth work
     Clay liner not required
        Normal digging                               $M,200
        Shale                                         6,290

Liner
     Clay
        With clay available                             320
        With clay purchase                              780
     Asphalt                                            280
     Synthetic                                          700
     None

Tailings excavation, loading,
  spreading and compacting                            1,500

Tailings transportation
     Truck                                            1,300
     Truck and rail                                   1,100
     Pipeline                                         1,270

Stabilization
     Vegetation
        No need to purchase soil                        130
        With soil purchase                              4MO
        Irrigation equipment                             30
     Riprap                                           2,280
     Gravel                                             H50
     Chemical                                           130

Fencing
     Chain link                                          50
     Security  (prison grade)                            160

Future Costs
     Irrigation equipment                               100
     Chemical  stabilization                             500
     Chain-link fence                                    10
     Security  (prison grade) fence                       20

Value of land                                            20
                                B-U9

-------
 fence.  As a result, the cost of uranium mill tailings  disposal  at  the



 model inactive mill site, using  a nitric acid leaching process, could  be




 expected to range between $69.2 and $75.7 million.








 B.4.2  Long-Term Radon and Hydrology Control



      It is unreasonable to expect that the uranium mill tailings can be




 completely isolated at the existing sites.  The concept of complete




 long-term isolation (of both radon and ground water)  essentially requires




 special site selection and emplacement techniques.  The NEC DGEIS (NR 79)




 describes  two methods  that conceivably will  meet  these  criteria:  deep




 disposal in an  open-pit mine and deep disposal in an  underground mine.








      In the case  of an open-pit  mine,  the  mill  tailings may be loosely




 deposited  in the  pit but enclosed in a watertight liner and cap,  or they




 can be  combined with asphalt  or  cement  to  prevent leaching into  the



 surface  and ground  water environment.   Table  B-21 presents cost  estimates




 which assume  an available  open-pit  coal mine  or copper quarry within 10




miles.   Long-term radon  and hydrology control could cost as little as $6.9




million.  This includes  only  expenses for dragline excavation of the



 tailings, truck and  rail  tailings transport, and loose tailings disposal



with an asphalt liner and cap.  These cost estimates  are relatively  low
                                    B-50

-------
                                 TABLE B-21

                      Cost Estimates for Deep Disposal
                  When a Nearby Open-Pit Mine Is Available

                         (thousands  in 1978 dollars)
     Task

Evacuate & load tailings

Tailings transportation
  Truck
  Truck & rail
  Pipeline

Tailings disposal
  Loose with liner & cap
  Cement fixation
    Thermal evaporator
    Filter bed
  Asphalt fixation
    Thermal evaporator
    Filter bed

Disposal of mine contents

Vegetation cover
  No need to purchase soil
  Soil purchase required
  Cost

$1,200
 1,330
 1,100
 1,300
 £1,600

17,900
10,830

24,930
17,840

28,130
   690
 4,600
                                    B-51

-------
 because it is assumed that there is an operating open-pit mine close to



 the mill tailings pile,  and that the mine owners are willing to cover the



 mill tailings at no cost as part of their post-operation reclamation of



 the mine site.  On the other hand,  costs could increase to $57.5 million,



 if the  mill tailings are deposited  in an abandoned open pit mine,



 transported by truck, dried by a thermal evaporator,  and incorporated into



 an asphalt matrix.   It is also assumed that  the disposal site  is



 stabilized with vegetation,  requiring the purchase of suitable top  soil.



 Unlike  the previous control levels,  however,  there is no long-term



 commitment to institutional  maintenance  and  the site  will  be available  for



 alternative future  u,ses.







     In  another  approach,  it  is assumed  that  a nearby abandoned



 underground mine  is available.   In this  case,  it is assumed  that the



 tailings will  need  to be  fixed  in an  asphalt  or cement  matrix  to prevent



 leaching.   Further,  holes will  be bored  into  the mine  cavities for



 depositing the asphalt or  cement matrix.  Cost  estimates  for deep disposal



of the mill tailings  in an underground mine are presented  in Table B-22.



 Implementing  this method of tailings  disposal would cost from $13.1



million to  $27.5 million.
                                    B-52

-------
                                 TABLE B-22

                      Cost Estimates of Deep Disposal
                When a Nearby Underground Mine Is Available

                         (thousands in  1978 dollars)
     Task

Evacuate & load tailings

Tailings transportation
  Truck
  Truck & rail
  Pipeline

Bore holes

Tailings disposal
  Cement fixation
    Thermal evaporator
    Filter bed
  Asphalt fixation
    Thermal evaporator
    Filter bed
  Cost

$1,200
 1,330
 1,100
 1,300

    20
17,900
10,830

24,930
17,840
                                     B-53

-------
                         References for Appendix B


(DA 77)      Dames & Moore, 1977, "An Evaluation of the Cost Parameters
             for
             Hypothetical Uranium Milling Operations and Ore
             Transportation Systems in the Western United States,"
             Argonne National Laboratory, Job No. 10263-001-07.

(DO 78)      Dodge Building Cost Services, 1978, 1978 Dodge Guide for
             Estimating Public Works Construction Costs. McGraw-Hill: New
             York, N.Y.

(FB 76-78)   Ford, Bacon and Davis Utah, Inc., "Phase II-Title 1,
             Engineering Assessment of Inactive Uranium Mill Tailings,"
             ?0 reports for Department of Energy Contract No.
          .   E(05-D-1*58, 1976-1978.

(ME 77)      Means, Robert Snow, 1977, Building Construction Cost Data
             1977. Robert Snow Means, Co., Inc.:  Duxbury, Mass.

(NR 76)      U.S. Nuclear Regulatory Commission, August 1976, "Final
             Generic Environmental Statement on the Use of Recycled
             Plutonium in Mixed Oxide Fuel in Light Water Cooled
             Reactors," NUREG-0002, Vol. H.

(NR 79)      U.S. Nuclear Regulatory Commission, April 1979, "Generic
             Environmental Impact Statement on Uranium Milling,"
             NUREG-0511.

(SM 78)      Smith, C. Bruce and Lambert, Janet A.,  June 1978,
             "Technology and Costs for Cleaning Up Land Contaminated with
             Plutonium," in "Selected Topics: Transuranium Elements in
             the General Environment," U.S. Environmental Protection
             Agency, ORP/CSD-78-1.

-------
                 APPENDIX-C
Toxicologies of Toxic Substances in Tailings

-------
         APPENDIX  C:  Toxicologies  of  Toxic-Substances  in-Tail ings








     The toxicologies  of  the  following  substances  found  in  tailings  are




 summarized:



               arsenic                   nitrate




               barium                    radium




               cadmium                   selenium




               chromium                 silver




               lead                      thorium




              mercury                   uranium




              molybdenum








C.I  Arsenic



     Arsenic is a metal apparently not essential to human nutrition.  It




is widely distributed  in nature and used estensively in medicine and




agriculture.  The pentavalent form is less toxic than the trivalent




(23 milligrams of arsenic taken as arsenic trioxide has been fatal




(JO 63)), but usually more teratogenic(l) (VE 78).








     Chronic poisoning produces skin abnormalities, proteinuria, anemia,




and swelling of the liver.  Some cardiac and nervous symptoms have been




associated in Japan with drinking well water containing 1 to 3 parts per
(1)Teratogenicity is the capability to cause abnormal fetal development.

-------
million of arsenic (TE 60).  Epidemiologic studies of chronic arsenic




poisoning in Antofagasta, Chile, found a high incidence of skin and




cardiovascular abnormalities; chronic coryza and abdominal pain, and some




chronic diarrhea in children who drank water containing 600 to 800 parts



per billion of arsenic (NA 77).  The incidence of skin lesions decreased by



a factor of about 16 when the arsenic content of the water was decreased to




80 parts per billion (NA 77), but the effects did not disappear completely.








     Chronic consumption of arsenic has also been linked with increased




incidence of lung cancer (VE 78) and skin cancer (VE 78, NA 77, GO 77).








C.2  Barium




     Barium is a metal apparently not essential to human nutrition.  It is




widely distributed in nature and used in  industry, medicine, and




agriculture.  Consumption of 550 to 600 milligrams of barium as barium




chloride has been reported to be fatal (SO 57).








     Ingested barium causes abnormal muscle stimulation due to induced




release of catacholamines  from  the adrenal medulla.  There is, however, no




evidence of chronic toxicity from long-term consumption of barium  in people



or  animals (NA 77, UN 77).








C.3 Cadmium




     Cadmium  is a metal  distributed in the environment in trace quantities




except  in some zinc, copper and other ores.   It is not essential to human
                                    C-2

-------
 nutrition.   It is used in industry.   Acute fatal poisoning with cadmium is




 difficult because cadmium salts cause vomiting when consumed.   Acute



 poisoning from consuming food or drink contaminated with  cadmium occurs 15




 to 30 minutes after  15 to 30 milligrams of cadmium  has been swallowed



 (EN 79).   Symptoms include continuous vomiting,  salivation,  choking sensa-



 tions, abdominal  pain,  and diarrhea.   Acute toxicity symptoms have been




 reported  in school children eating popsicles containing 13  to 15 milligrams




 of cadmium  per liter (EN 76).








      Absorbed cadmium is toxic  to all body organs,  damaging  cells and




 enzyme systems.   Little  is excreted,  so it accumulates over  the lifetime.



 In Japan, where people  consumed about 0.6  milligrams of cadmium per day,




 chronic toxicity  was reported  (EN 76).   The illness was called "Itai-itai"




 disease,  and  resulted in bone and kidney damage.  Symptoms were seen mostly




 in older women whose diets  were very  poor,  especially lacking in protein




 and  calcium (UN 77,  NA 77).  Since cadmium toxicity is moderated by



 calcium, zinc, copper and maganese (UN  77)  and selenium, iron, vitamin C,




 and  protein (GO 77), diet  is important.








     The earliest  symptom  of chronic  cadmium toxicity is kidney damage,



 evidenced by  increased protein  in the urine.  This occurs when the cadmium




 level  in the  renal cortex reaches 200 to 300 micrograms per gram of wet




weight (EN 76, EN  79).  This 200-microgram  level can be reached after




consuming about 350 micrograms  of cadmium a day for 50 years (EN 76).




Consumption of only 60 micrograms a day has been estimated to cause kidney
                                   C-3

-------
damage in 1% of the exposed group (EN 79).   The body retains as much




cadmium from smoking one pack of cigarettes per day as from ingesting  25




micrograms of cadmium a day (EN 79).








     Cadmium has caused reproductive disturbances and teratogenesis in



experimental animals fed high levels (VE 78, UN 77, EN 79, NA 77).  It has




also been implicated in human hypertension, cardiac problems, and prostatic




carcinogenesis (UN 77, EN 79, GO 77, NA 77), but the connection is not




definitive.








C.4  Chromium




     Chromium is a metal that is essential to human nutrition; it is




involved in glucose and lipid metabolism and protein synthesis (UN 77).  It




is widely distributed in nature and has many industrial applications.  Oral




toxicity is low; humans can tolerate 500 milligrams daily of chromic




sesquioxide (VE  78).  Hexavalent chromium  is more  toxic than trivalent




(UN  77, VE  78).  The  principle  damage  in acute chromium poisoning is



tubular necrosis in the kidney.  Large enough doses of hexavalent chromium




can  cause gastrointestinal tract hemorrhaging, but lifetime exposure  of



laboratory  animals to less than 5  parts per million of chromium  in drinking




water caused  no  reported  effects (NA 77, UN 77).








      No  information exists on the  effects  of chronic  consumption in humans.
                                    C-4

-------
C.5  Lead



     Lead is a metal widely distributed in nature and used extensively in




industry and agriculture; it is not essential to human nutrition.  The




amount of lead absorbed before symptoms of toxicity appear is rarely known;



however, one man ingested 3.2 milligrams per day for two years before




symptoms occurred (NA 72).








     Toxicity is usually related to levels of lead in the blood.  A level




of 330 micrograms per 100 grams of blood has been associated with acute




brain pathology and death in children (NA 72).  Levels of 80 micrograms per




100 grams of blood and greater have been associated with brain, nervous



system, and kidney pathology; severe colic; seizures; paralysis; blindness,




and ataxia in children (NA 72, GO 77, NA 77, UN 77).  Subclinical (hard to




detect because clinical symptoms are lacking) effects on the central




nervous system, the red blood cells, the kidneys, and enzymes may occur at




levels of 40 to 80 micrograms of lead per 100 grams of blood (GO 77).  In




women and children some changes in red cells can be detected at 25 to 30




micrograms per 100 grams of blood (NA 77).








     Drinking water containing 100 micrograms of lead per liter results in




blood lead levels of 25 to 40 micrograms per 100 grams of blood, (UN 77,




NA 77).  Such exposure could lead to some clinical lead poisoning,




particularly in children (NA 77).
                                   C-5

-------
C.6  Mercury




     Mercury is a metal not essential to human nutrition.  It is distributed




in nature as a trace element except in some metal ores, and has many indus-




trial applications.  Consumption of 158 milligrams of mercury as mercuric



iodide has been reported fatal (VE 78).  Effects of nonfatal doses of



mercury salts include local irritation, coagulation, and necrosis of tissue,




kidney damage, colitis, hallucinations, and a metallic taste in the mouth.








     As with lead, chronic mercury poisoning develops slowly.  Many of the




symptoms relate to the nervous system:  impaired walking, speech, hearing,




vision, or chewing; insomnia; anxiety; mental disturbances; and ataxia.



There also may be damage to kidneys, blood cells, gastrointestinal tract,




and enzyme systems (NA 77, VE 78).  Studies of Minamata disease (methyl




mercury poisoning) suggest that consumption of one milligram of mercury per




day as methyl mercury over a period of several weeks will be fatal (VE 78);




consumption of 0.3 milligrams per day will cause clinical symptoms of




mercury poisoning (UN 77, NA 77).  About 10 times as much methyl mercury



would be absorbed as inorganic mercury (GO 77).








     Mercury passes through the placenta.  It has caused cases of Minamata



disease by fetal exposure (NA 77), and may cause birth defects (VE 78,



UN 77).
                                    C-6

-------
C.7  Molybdenum
     Molybdenum is a metal essential  in trace quantities for human
nutrition.  It is present in nature in trace quantities, except in some
ores.  It has been widely used in industry.  There are no data for acute
toxicity of molybdenum in humans following ingestion, but the animal data
(VE 78) shows that it must be in the  range of hundreds of milligrams per
kilogram of body weight.

     Chronic toxicity has been seen in persons who have consumed 10 to 15
milligrams of molybdenum per day (CH  79).  Clinical signs of the toxicity
were a high incidence of a gout-like  disease and increased urinary
excretion of copper and uric acid.  Increased urinary copper excretion has
been observed in persons who consumed 0.5 to 1.5 milligrams of molybdenum
per day, and in persons who drank water containing 0.15 to 0.20 milligrams
of molybdenum per liter, but not in persons who drank water containing up
to 0.05 milligrams of molybdenum per  liter (CH 79).  The significance of
the increased copper excretion is not known.

C.8  Nitrate
     Nitrate, a salt of nitric acid,  is the stable form of combined
nitrogen in oxygenated water, and all nitrogenous materials in natural
waters tend to be converted to nitrate (NA 77).  The fatal dose has been
estimated as 120 to 600 milligrams of nitrate (27 to 136 milligrams of
nitrate-nitrogen) per kilogram of body weight (BU 61).  Burden estimated
the maximum permissible dose of nitrate-nitrogen as 12 milligrams  in a
                                    C-7

-------
three-kilogram infant and 240 milligrams in a 60-kilogram adult (BU 61).




Apparently nitrate is converted to nitrite in the gastrointestinal tract,




and the absorbed nitrite causes the toxicity (NA 72a, NA 77).








     Chronic toxicity is usually observed in children.  Symptoms of



toxicity have been reported in children drinking water with 11 milligrams




or more of nitrate-nitrogen per liter, but not in those consuming nine




milligrams or less per liter (NA 72a, NA 77).








     Nitrates can be reduced to nitrites and combined with secondary amines




or amides to form N-nitroso compounds, which are considered carcinogens



(NA 72a, NA 77).








C.9  Radium




     Radium is a metal widely distributed in the environment in trace




quantitities except in some ores.  It is not essential to human nutrition.




In the past it was widely used in industry and medicine.  No reliable data




exist on acute radium toxicity in humans (SI 45) and chemical toxicity, if




any, is expected to be masked by radiation damage (VE 78).








     Chronic intake of radium is expected to be carcinogenic, especially in




bone.  Radium isotopes are expected to have roughly the same chronic




toxicity per unit of activity (picocurie) consumed, but not per unit of




weight (microgram) consumed (IN 79).  Radium-227, which is one thousand to
                                   C-8

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ten  thousand  times  less  toxic  than  other radium  isotopes  (IN 79), may be an




exception.








     Consuming one  picocurie of radium per day continuously entails a risk




of developing cancer of  about  one in  10 million  per year  (EN 76).









C.10  Selenium



     Selenium, a metal,  is widely but unevenly distributed in nature.  It




is essential in human nutrition in  trace amounts (NA 77).  It is used in




industry and medicine.








     Drinking water containing nine milligrams of selenium per liter for'a




three month period caused development of symptoms of selenium toxicity:




listlessness, loss of hair, and loss of mental alertness  (EN 76).  Other




symptoms of selenium toxicity include garlicky breath, depression, derma-




titis, nervousness, gastrointestinal disturbance, and skin discoloration




(EN 76, NA 77).  Consumption of one milligram per kilogram of body weight




per day may cause chronic selenium poisoning (GO 77).  Bad teeth, gastro-




intestinal disturbances and skin discoloration have been associated with




consumption of 0.01 to 0.1 milligram of selenium per kilogram of body




weight per day (EN 76).







     Selenium has also been suggested to cause increased teratogenesis and




dental caries, but there are little data on these questions (VE 78).
                                   C-9

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C.ll  Silver




     Silver is a metal distributed in trace levels in the environment



except in some ores.  It is not essential to human nutrition.  It is widely



used in industry, medicine, photography, and art.  Data on acute toxicity



in people are sparse, but consumption of 140 milligrams of silver nitrate



causes severe gastroenteritis, diarrhea, spasms, and paralysis leading to



death (VE 78).








     Chronic toxicity from soluble silver salts is usually associated with



argyria, a permanent blue-grey discoloration of the skin caused by




deposited silver (EN 76, NA 77).  Silver deposited in tissue, especially in



the skin, apparently is retained there indefinitely (EN 76), perhaps as a



harmless silver-protein complex, or as silver sulfide or selenide (VE 78).



If one gram of accumulated silver causes borderline argyria, as postulated



by the National Academy of Sciences, this level would be reached after 50



years of drinking water containing 50 micrograms of silver per liter, or



after 91 years at 30 micrograms per liter (NA 77).  Prolonged consumption



of silver salts may also cause liver and kidney damage and changes in blood



cells (VE 78).








C.12  Thorium




     Thorium is a metal distributed in the environment in trace quantities,



except in some ores.  It is not essential to human nutrition.  It is used



in industry and as a nuclear power source.   It was formly used in medicine.
                                   C-10

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      There are no data on toxicity in humans.   In animal studies,  thorium



 given orally at levels near one gram per kilogram of body weight causes



 death in half of the animals (VE 78).








      Chronic toxicity appears limited  to carcinogenesis  associated with the



 radioactivity of the thorium.  The various  isotopes  of thorium are expected




 to  vary greatly in toxicity, considered  on  a per-unit-activity basis



 (IN 79);  all are expected to produce radiation-related cancers.








 C.13  Uranium



     Uranium is  a metal widely  distributed  in  the  environment in trace



 quantities.   It  is not essential  to human nutrition.  It  is used in the




 nuclear power industry.








     Acute toxicity in humans has  been estimated to occur, based on kidney




 damage, following absorption of 0.1 milligram per kilogram of body weight?



 some deaths would be expected following absorption of one milligram per



 kilogram of body  weight (LU  58).   If 20% of the uranium in water is



 absorbed, this would be equivalent  to 17.5 milligrams and 175 milligrams



 per liter of uranium, respectively,  for a 70-kilogram man.  Oral doses of



 10.8 milligrams of uranium (as uranyl nitrate hexahydrate) apparently



caused no kidney  damage (HU  69).  However, consumption of 470 milligrams of



uranium (one gram  of uranyl nitrate) caused vomiting, diarrhea,  and some




albuminuria (BU 55).
                                   C-ll

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     Building up a tolerance to uranium is apparently possible.  Spoor




cites reports from the medical literature of the 1890's where uranyl




nitrate was used to treat diabetes, starting with a conditioning dose of




about 60 milligrams of uranyl nitrate three times a day after meals and



gradually raising the dose to six grains of uranyl nitrate a day (SP 68).



If such doses were given without conditioning, they would be expected to be




fatal.








     Chronic toxicity may also be related to enzyme poisoning in the




kidneys (LU 58), with some liver damage as a result of the kidney damage




(VE 78).  Experiments with animals which inhaled uranium compounds for a



year showed mild kidney changes associated with about one microgram of




uranium per gram of kidney.  Extending these results to a human kidney




weight of 300 grams, absorption of 20% of uranium in water and deposition




of 11% of absorbed uranium in the kidney retained with a 15-day half-life




(SP 73) could cause chronic chemical toxicity in humans who drink water




containing about 315 micrograms of uranium per liter.








     Uranium can also cause chronic  toxicity  in the form of radiation-



related carcinogenesis.  The various uranium  isotopes vary greatly in their




carcinogenic potentials as considered  on a unit activity basis  (IN 79).



There  is some question as  to whether radiation-related cancer  or chemical




toxicit  will be the major response  to some uranium isotopes.
                                    C-12

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                          References- for Appendix- C

(BU 55)  Butterworth, A. The Significance and Value of Uranium in Urine
         Analysis, Trans. Ass. Indstr. Med. Offrs. 5_:36-43 (1955).

(BU 61)  Burden, E.H.W.J.  The Toxicology of Nitrates and Nitrites with
         Particular Reference to the Potability of Water Supplies.  Analyst
         86:429-433 (1961).

(CH 79)  Chappell, W.R., et al -. , "Human Health Effects of Molybdemum in
         Drinking Water^HTSlPA", Health Effects Research Laboratory,
         EPA-600/1-79-006, 1979.

(EN 76)  Environmental Protection Agency.  National Interim-Primary
         Drinking- Water Regulations , EPA-570/9-76-003.  USEPA, Ottice of
         Water Supply, Washington, D.C., 1976.

(EN 79)  Environmental Protection Agency.  Cadmium- Ambient Water Quality
         Criteria.  Office of Water Planning and Standards, USEPA,
         Washington, D.C., 1979.

(GO 77)  Goyer, R.A. and Mehlman, M.A. editors, Toxicology of • Trace
         Elements, Advances in Modern Toxicology, Vol. 2.  John wney &
         Sons, New York, 1977.

(HU 69)  Hursh, J.B., e£ al^, Oral Ingestion of Uranium by Man, Health
         Physics 11:619-621 (1969).

(IN 79)  International Commission on Radiological Protection,  Limits for
         Intakes of Radionuelides by Workers,  ICRP Publications 30,
         Pergamon Press, New York, 1979.

(JO 63)  Johnstone, R.M. , "Metabolic Inhibitors 2" (1963), cited by
         Underwood, E.J., (see UN 77).

(LU 58)  Luessenhop, J., et aK,  The Toxicity in Man of Hexavalent Uranium
         Following Intravenous Administration, Amer.  J. Roentgenol.
         72:83-100 (1958).
(NA 72)  National Academy of Sciences, Lead: -Airborne- Lead in Perspective-,
         NAS-NRC, Washington, D.C., 1972.

(NA 72a) National Academy of Sciences, Accumulation- of -Nitrate, Committee
         on Nitrate Accumulation, NAS-NRC,  Washington, i*/z,
(NA 77)  National Academy of Sciences, Drinking Water and- Health^ Part^^
         Chapters- 1-5, NAS Advisory Center on Toxicology,  Assembly of Life
         Sciences, Washington, 1977.
                                   C-13

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(SI 45)  Silberstein, H.E., Radium Poisoning, AECD-2122, USAEC Technical
         Information Division, Oak Ridge, 1945.

(SO 57)  Sollman, T., A Manual of Pharmacology, 8th edition, W.B. Saunders
         Co., Philadelphia, 1957.

(SP 68)  Spoor, N.L., Occupational Hygiene-Standards-for Natural Uranium,
         AHSB(RP)77.  Radiological Protection Division, UKAEA, Harwell,
         1968.

(SP 73)  Spoor N.L. and Hursh, J.B., Protection Criteria, pp. 241-270 in
         Uranium-Plutonium-Transplutonic Elements,  B.C. Hodge, J.N.
         Stannard and J.B. Hursh, editors,  Springer-Verlag,  New York, 1973.

(TE 60)  Terada,  H., et al.,  Clinical Observations  of  Chronic Toxicosis by
         Arsenic, Ninon Tlnsho,  18:2394-2403, (1960),  (EPA translation No.
         TR 106-74).

(UN 77)  Underwood, E.J.,  Trace•Elements in-Human-and•Animal•Nutrition,
         Fourth Edition, Academic Press, New York,  1977.

(VE 78)  Venugopal, B. and Luckey,  T.D., Metal Toxicity in Mammals  .2,
         Chemical Toxicity of Metals and-Metaloids.  Plenum Press, New York,
         1978.
                                  C-14

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      APPENDIX D
The Proposed Standards

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     The Administrator of the Environmental Protection Agency hereby



proposes to add a Part 192 to Title 40 of the Code of Federal Regulations




as follows:
             Part 192 - ENVIRONMENTAL PROTECTION STANDARDS FOR




                            URANIUM MILL TAILINGS








      Subpart A — Environmental Standards for the  Disposal  of Residual




        Radioactive Materials from Inactive Uranium Processing Sites




192.01     Applicability




192.02     Definitions




192.03     Standards




192.04     Effective date








             Subpart B - Environmental Standards for Cleanup of



             Open  Lands  and  Buildings  Contaminated  with Residual




        Radioactive Materials from Inactive Uranium Processing Sites




192.10     Applicability




192.11     Definitions




192.12     Standards




192.13     Effective date

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                           Subpart C — Exceptions



192.20     Criteria for exceptions



192.21     Remedial actions for exceptional circumstances








(Authority: Section 275 of the Atomic Energy Act  of 1954, 42 U.S.C. 2022,



as amended by the Uranium Mill Tailings Radiation Control Act of 1978,



PL 95-604.)








        Subpart A — Environmental Standards  for Disposal  of Residual



        Radioactive Materials from Inactive Uranium Processing Sites



192.01    Applicability




     This subpart applies to the disposal of residual radioactive material



at any designated processing site or depository site as part of any



remedial action conducted under Title I of the Uranium Mill Tailings



Radiation Control Act of 1978 (PL 95-604), or following any use of sub-



surface minerals at such a site.








192.02    Definitions




     (a)  Unless otherwise indicated in this subpart, all terms shall have



the same meaning as in Title I of the Uranium Mill Tailings Radiation



Control Act of 1978 and the Atomic Energy Act.



     (b)  Remedial action means any action performed under Section 108 of



the Uranium Mill Tailings Radiation Control Act of 1978.



     (c)  Disposal means any remedial action intended to assure the



long-term,  safe,  and environmentally sound stabilization of residual



radioactive materials.

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      (d)  Disposal  site  means  the region within the smallest practical
boundaries around residual radioactive material  following completion of
disposal.
      (e)  Depository site means a disposal site  selected under Section
104(b) or 105(b) of the  Uranium Mill  Tailings Radiation Control Act of
1978.
      (f)  Aquifer means  a geologic formation, group of formations, or
portion of a formation capable of yielding usable quantities of ground
water to wells or springs.
      (g)  Ground water means water below the land surface in the zone of
saturation.
      (h)  Underground source of drinking water means:
          (1) an aquifer supplying drinking water for human consumption, or
          (2) an aquifer in which the ground water contains less than
10,000 milligrams/liter  total dissolved solids.
      (i)  Curie (Ci) means the amount of radioactive material which
produces 37 billion nuclear transformations per  second.  One picocurie
(pCi) - 10-12 ci.
      (j)  Surface waters means "waters of the United States, including the
territorial seas" ("navigable waters") ap defined in the Federal Register,
Volume 44, page 32901, June 7, 1979.  (Comment;  This definition is taken
from  the Regulations for the National Pollutant Discharge Elimination
System, 40 CPR 122.3(t).  In essence, it includes all U.S. surface waters
which the public may traverse, enter, or draw food from.)

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192.03    Standards

     Disposal of residual radioactive materials shall be conducted in a

way that provides a reasonable expectation  that for at  least one  thousand

years following disposal —

          (a) The average annual release of radon-222 from a disposal site

to the atmosphere by residual radioactive materials will not exceed

2 pCi/m2-8ec.*

          (b) Substances released from residual radioactive materials

after disposal will not cause

              (1)  the concentration of that substance in any underground

source of drinking water to exceed the level specified  in Table A, or

              (2) an increase in the concentration of that substance in

any underground source of drinking water, where the concentration of that

substance prior to remedial action exceeds the level specified in Table A

for causes other than residual radioactive materials.

          This subsection shall apply to the dissolved portion of any

substance listed in Table A at any distance greater than 1.0 kilometer

from a disposal site that is part of an inactive processing site, or

greater than 0.1 kilometer if the disposal site is a depository site.
* NOTj-!  Ths radon emitted from a tailings site after disposal will come
from the tailings and from materials covering them.  Radon emissions from
the covering materials should be estimated as part of developing a
disposal plan for each site.  These plans will be reviewed and concurred
with by the Nuclear Regulatory Commission prior to disposal.  After
disposal, the radon emission standard is satisfied if the emission rate is
less than or equal to 2 pCi/m2-8ec plus the emission rate expected from
the disposal materials.

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           (c)   Substances  released from the disposal site after disposal


will not cause  the concentration of any harmful dissolved  substance in any

surface waters  to  increase above  the  level that would otherwise prevail.




192.04  Effective date

     The standards of this Subpart shall be effective 60 days after final

promulgation of this rule.




              Subpart B — Environmental Standards for Cleanup

           of Open Lands and Buildings Contaminated with Residual


        Radioactive Materials from Inactive Uranium Processing Sites


192.10   Applicability

     This subpart applies  to open lands and buildings which are part of any

processing site designated by the Secretary of Energy under PL 95-604,


Section 102.  Section 101 of PL 95-604, states that "processing site"


means —
                                                              i
     (A) any site,  including the mill, containing residual radioactive

materials at which all or  substantially all of the uranium was produced

for sale to any Federal agency prior to January 1, 1971 under a contract

with any Federal agency, except in the case of a site at or near Slick


Rock, Colorado, unless —

        (i) such site was owned or controlled as  of January 1, 1978, or is


     thereafter owned or controlled, by any Federal agency, or

        (ii) a license (issued by the (Nuclear Regulatory) Commission or

     its predecessor agency under the Atomic Energy Act of 1954 or by a

     State as permitted under section 274 of such Act) for the production

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     at such site of any uranium or thorium product derived from ores is in




     effect on January 1, 1978, or is issued or renewed after such date;




     and




     (B) any other real property or improvement thereon which —



        (i) is in the vicinity of such site, and




        (ii) is determined by the Secretary, in consultation with the



     Commission, to be contaminated with residual radioactive materials




     derived from such site.




Any ownership or control of an area by a Federal agency which is acquired




pursuant to a cooperative agreement under this title shall not be treated




as ownership or control by such agency for purposes of subparagraph (A)(i).



A license for the production of any uranium product from residual radioac-




tive materials shall not be treated as a license for production from ores



within  the meaning of subparagraph (A)(ii) if such production is in




accordance with section 108(b).








192.11   Definitions




     (a) Unless otherwise indicated in this subpart, all terms shall have




the same meaning as defined in Title  I of the Uranium Mill Tailings




Radiation Control Act of 1978.




     (b)  Remedial action means any action performed under Section 108 of



the Uranium Mill Tailings Radiation Control Act of 1978.




     (c) Open land means any surface  or subsurface land which is not a




disposal site and is not covered by a building.

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      (d) Working Level (WL) means any combination of short-lived radon




 decay products in one liter of air that will result in the ultimate emis-



 sion of alpha particles with a total energy of 130 billion electron volts.




      (e) Dose equivalent  means absorbed dose multiplied by appropriate



 factors to account for differences in biological effectiveness due to the




 type and energy of the radiation and other factors.   The unit of dose



 equivalent is the "rem."




      (f) Curie (Ci) means  the  amount  of  radioactive material  which



 produces 37 billion nuclear transformations per second.   One  picocurie



 (pCi) - 10-12 ci.








 192.12     Standards




     Remedial actions  shall be  conducted so as  to provide reasonable




 assurance  that ~




     (a)   The average  concentration of radium-226 attributable to residual




 radioactive material  from  any  designated processing site  in any  5 cm




 thickness  of  soils or  other materials on open land within  1 foot of the



 surface, or in any 15  cm thickness below 1  foot, shall not exceed 5 pCi/gm.




     (b)   The  levels of radioactivity in any occupied or occupiable




 building shall not exceed  either  of the  values  specified  in Table B because




 of residual radioactive materials from any designated processing site.



     (c)   The  cumulative lifetime radiation dose equivalent to any organ




of the body of a maximally exposed individual resulting from the presence




of residual radioactive materials or byproduct materials shall not exceed




the maximum dose equivalent which could occur from radium-226 and its




decay products under paragraphs (a) and (b) of this section.

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192.13   Effective date




     The standards of this Subpart shall be effective 60 days after



promulgation of this rule.








                           Subpart C — Exceptions



192.20  Criteria for exceptions




     Exceptions to the standards may be justifiable under any of the



following circumstances:




     (a)  Public health or safety would be unavoidably endangered in




attempting to meet one or more of the requirements of Subpart A or




Subpart B.




     (b)  The goal of environmental protection would be better served by




not satisfying cleanup requirements for open land, Sec. 192.12(a) or the




corresponding part of Sec. 192.12(c).   To justify an exception to these



requirements there should be a clearly unfavorable imbalance between the




environmental harm and the environmental and health benefits which would



result from implementing the standard.  The likelihood and extent of




current and future human presence at the site may be considered in




evaluating these benefits.




     (c)  The estimated costs of remedial actions to comply with the



cleanup requirements for buildings, Sec 192.12(b) or the corresponding




part of Sec. 192.12(c), are unreasonably high relative to the benefits.



Factors which may be considered in this judgment include the period of




occupancy, the radiation levels in the most frequently occupied areas, and
                                      8

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the residual useful lifetime  of  the  building.   This  criterion can  only be




used when the values in Table B  are  only slightly exceeded.



     (d)  There is no known remedial action  to  meet  one  or more  of the




requirements of Subpart A or Subpart B.  Destruction and condemnation of



buildings are not considered  remedial  actions for this purpose.








192.21  Remedial actions for exceptional circumstances




     Section 108 of PL 95-604 requires the Secretary of Energy to  select




and perform remedial actions with the concurrence of the Nuclear Regula-



tory Commission and the full participation of any State which pays part of




the cost, and in consultation, as appropriate, with affected Indian tribes



and the Secretary of the Interior.  Under exceptional circumstances satis-




fying one or more of the conditions  192.20(a), (b),  (c), and (d), the




Department of Energy may select  and  perform remedial actions, according to




the procedures of Sec. 108, which come as close to meeting the standard to




which the exception applies as is reasonable under the exceptional circum-




stances.  In doing so, the Department of Energy shall inform any private




owners and occupants of affected properties and request their comments on




the selected remedial actions.  The Department of Energy shall provide any




such comments to the parties involved in implementing Sec. 108 of




PL 95-604.  The Department of Energy shall  also inform the Environmental



Protection Agency of remedial actions for exceptional circumstances under




Subpart C of this  rule.

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                                  TABLE A

     Arsenic  	   0.05    milligram/liter

     Barium 	   1-0    milligram/liter

     Cadmium	   0.01    milligram/liter

     Chromium 	   0.05    milligram/liter

     Lead	   0.05    milligram/liter

     Mercury  	   0.002  milligram/liter

     Molybdenum -•	   0.05    milligram/liter

     Nitrogen (in nitrate) 	  10.0    milligram/liter

     Selenium 	   0.01    milligram/liter

     Silver 	   0.05   milligram/liter



Combined radium-226 and radium-\228	   5.0   pCi/liter

Gross alpha particle activity (including

 radium-226 but excluding radon and uranium)	  15.0   pCi/liter

Uranium	10.0   pCi/liter







                                   TABLE  B

Average Annual Indoor
 Radon Decay Product Concentration
  (including background) 	 0.015 WL

Indoor Gamma Radiation
  (above background) 	 0.02  milliroentgens/hour
                                     10

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                                     TECHNICAL REPORT DATA
                              (Please read Instructions on the reverse before completing)
  i. REPORT NO,
   EPA  520/4-80-011
                                                             3. RECIPIENT'S ACCESSION NO.
  4. TITLE AND SUBTITLE
      Draft Environmental Impact Statement  for  Remedial
      Action Standards  for Inactive Uranium Processing
      Sites
              5. REPORT DATE

                   December. ' 1 Qftf)
              6. PERFORMING ORGANIZATION CODE
 7. AUTHOR(S)
                                                             8. PERFORMING ORGANIZATION REPORT NO.
 9. PERFORMING ORGANIZATION NAME AND ADDRESS
      U.  S. Environmental  Protection Agency
      Office of Radiation  Programs (ANR-460)
      401 M Street, S. W.
      Washington, D. C. 20460
              10. PROGRAM ELEMENT NO.
              11. CONTRACT/GRANT NO.
 12. SPONSORING AGENCY NAME AND ADDRESS
                                                             13. TYPE OF REPORT AND PERIOD COVERED
                                                                  Draft
                                                             14. SPONSORING AGENCY CODE
                                                                  200/03
 15. SUPPLEMENTARY NOTES
 16. ABSTRACT            ^^  ————^	
           The  Environmental Protection Agency is proposing  standards for disposing of
     uranium mill tailings from  inactive processing sites and  for cleaning up
     contaminated open land and  buildings.   These standards  were developed pursuant to
     the Uranium Mill Tailings Radiation Control Act of 1978 (Public Law 95-604).
     This Act requires EPA to promulgate standards to protect  the environment and
     public health and safety from radioactive and nonradioactive hazards posed by
     uranium mill tailings at designated inactive processing sites.   The Draft
     Environmental Impact Statement examines health, technical,  cost, and other
     factors relevant to determining standards.  The proposed  standards for disposal of
     the tailings piles cover radon emissions from the tailings  to the air, protection
     of surface  and ground water from radioactive and nonradioactive contaminants, and
     the length  of time the disposal system  should provide a reasonable expectation
     of meeting  these standards.  The proposed cleanup standards  limit indoor radon
     decay product concentrations and gamma  radiation levels and  the residual radium
     concentration of contaminated land  after cleanup.
17.
                                KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
b.lDENTIFIEHS/OPEN ENDED TERMS
                                                                          c. COSATI Field/Group
 uranium  mill tailings
 Uranium  Mill Tailings Radiation  Control Act
   of 1978
 inactive uranium mill sites
 radioactive  waste disposal
 radon
 radium-226
                                               19. SECURITY CLASS (ThisReport)
                           21. NO. OF PAGES
    Release Unlimited
                                               0. SECURITY CLASS (Thispage)
                                                 Unclassified
                           22. PRICE
EPA Form 2220-1 (Rev. 4-77)   PREVIOUS EDITION is OBSOLETE
                                                *U.8. GOVERNMENT PRINTING OFFICE:1981  341-082/202  1-3

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