[Code of Federal Regulations]

[Title 40, Volume 24]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 40CFR192.20]



[Page 23-25]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 192_HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND 

THORIUM MILL TAILINGS--Table of Contents

 

                        Subpart C_Implementation

 

Sec.  192.20  Guidance for implementation.





    Section 108 of the Act requires the Secretary of Energy to select 

and perform remedial actions with the concurrence of the Nuclear 

Regulatory Commission and the full participation of any State that pays 

part of the cost, and in consultation, as appropriate, with affected 

Indian Tribes and the Secretary of the Interior. These parties, in their 

respective roles under section 108, are referred to hereafter as ``the 

implementing agencies.'' The implementing agencies shall establish 

methods and procedures to provide ``reasonable assurance'' that the 

provisions of Subparts A and B are satisfied. This should be done as 

appropriate through use of analytic models and site-specific analyses, 

in the case of Subpart A, and for Subpart B through measurements 

performed within the accuracy of currently available types of field and 

laboratory instruments in conjunction with reasonable survey and 

sampling procedures. These methods and procedures may be varied to suit 

conditions at specific sites. In particular:

    (a)(1) The purpose of Subpart A is to provide for long-term 

stabilization and isolation in order to inhibit misuse and spreading of 

residual radioactive materials, control releases of radon to air, and 

protect water. Subpart A may be implemented through analysis of the 

physical properties of the site and the control system and projection of 

the effects of natural processes over time. Events and processes that 

could significantly affect the average radon release rate from the 

entire disposal site should be considered. Phenomena that are localized 

or temporary, such as local cracking or burrowing of rodents, need to be 

taken into account only if their cumulative effect would be significant 

in determining compliance with the standard. Computational models, 

theories, and prevalent expert judgment may be used to decide that a 

control system design will satisfy the standard. The numerical range 

provided in the standard for the longevity of the effectiveness of the 

control of residual radioactive materials allows for consideration of 

the various factors affecting the longevity of control and stabilization 

methods and their costs. These factors have different levels of 

predictability and may vary for the different sites.

    (2) Protection of water should be considered on a case-specific 

basis, drawing on hydrological and geochemical surveys and all other 

relevant data. The hydrologic and geologic assessment to be conducted at 

each site should include a monitoring program sufficient to establish 

background groundwater quality through one or more upgradient or other 

appropriately located wells. The groundwater monitoring list in Appendix 

IX of part 264 of this chapter (plus the additional constituents in 

Table A of this paragraph) may be used for screening purposes in place 

of Appendix I of part 192 in the monitoring program. New depository 

sites for tailings that contain water at greater than the level of 

``specific retention'' should use aliner or equivalent. In considering 

design objectives for groundwater protection, the implementing agencies 

should give priority to concentration levels in the order listed under 

Sec.  192.02(c)(3)(i). When considering the potential for health risks 

caused by human exposure to known or suspected carcinogens, alternate 

concentration limits pursuant to paragraph 192.02(c)(3)(ii) should be 

established at concentration levels which represent an excess lifetime 

risk, at a point of exposure, to an average individual no greater than 

between 10-4 and 10-6.



     Table A to Sec.   192.20(a)(2)--Additional Listed Constituents

Nitrate (as N)

Molybdenum

Combined radium-226 and radium-228

Combined uranium-234 and uranium-238

Gross alpha-particle activity (excluding radon and uranium)





    (3) The plan for remedial action, concurred in by the Commission, 

will specify how applicable requirements of subpart A are to be 

satisfied. The plan



[[Page 24]]



should include the schedule and steps necessary to complete disposal 

operations at the site. It should include an estimate of the inventory 

of wastes to be disposed of in the pile and their listed constituents 

and address any need to eliminate free liquids; stabilization of the 

wastes to a bearing capacity sufficient to support the final cover; and 

the design and engineering specifications for a cover to manage the 

migration of liquids through the stabilized pile, function without 

maintenance, promote drainage and minimize erosion or abrasion of the 

cover, and accommodate settling and subsidence so that cover integrity 

is maintained. Evaluation of proposed designs to conform to subpart A 

should be based on realistic technical judgments and include use of 

available empirical information. The consideration of possible failure 

modes and related corrective actions should be limited to reasonable 

failure assumptions, with a demonstration that the disposal design is 

generally amenable to a range of corrective actions.

    (4) The groundwater monitoring list in Appendix IX of part 264 of 

this chapter (plus the additional constituents in Table A in paragraph 

(a)(2) of this section) may be used for screening purposes in place of 

Appendix I of part 192 in monitoring programs. The monitoring plan 

required under Sec.  192.03 should be designed to include verification 

of site-specific assumptions used to project the performance of the 

disposal system. Prevention of contamination of groundwater may be 

assessed by indirect methods, such as measuring the migration of 

moisture in the various components of the cover, the tailings, and the 

area between the tailings and the nearest aquifer, as well as by direct 

monitoring of groundwater. In the case of vicinity properties (Sec.  

192.01(l)(2)), such assessments may not be necessary, as determined by 

the Secretary, with the concurrence of the Commission, considering such 

factors as local geology and the amount of contamination present. 

Temporary excursions from applicable limits of groundwater 

concentrations that are attributable to a disposal operation itself 

shall not constitute a basis for considering corrective action under 

Sec.  192.04 during the disposal period, unless the disposal operation 

is suspended prior to completion for other than seasonal reasons.

    (b)(1) Compliance with Sec.  192.12(a) and (b) of subpart B, to the 

extent practical, should be demonstrated through radiation surveys. Such 

surveys may, if appropriate, be restricted to locations likely to 

contain residual radioactive materials. These surveys should be designed 

to provide for compliance averaged over limited areas rather than point-

by-point compliance with the standards. In most cases, measurement of 

gamma radiation exposure rates above and below the land surface can be 

used to show compliance with Sec.  192.12(a). Protocols for making such 

measurements should be based on realistic radium distributions near the 

surface rather than extremes rarely encountered.

    (2) In Sec.  192.12(a), ``background level'' refers to the native 

radium concentration in soil. Since this may not be determinable in the 

presence of contamination by residual radioactive materials, a surrogate 

``background level'' may be established by simple direct or indirect 

(e.g., gamma radiation) measurements performed nearby but outside of the 

contaminated location.

    (3) Compliance with Sec.  192.12(b) may be demonstrated by methods 

that the Department of Energy has approved for use under Pub. L. 92-314 

(10 CFR part 712), or by other methods that the implementing agencies 

determine are adequate. Residual radioactive materials should be removed 

from buildings exceeding 0.03 WL so that future replacement buildings 

will not pose a hazard [unless removal is not practical--see Sec.  

192.21(c)]. However, seal ants, filtration, and ventilation devices may 

provide reasonable as sur ance of reductions from 0.03 WL to below 0.02 

WL. In unusual cases, indoor radiation may exceed the levels specified 

in Sec.  192.12(b) due to sources other than residual radioactive 

materials. Re medial actions are not required in order to comply with 

the standard when there is reasonable assurance that residual 

radioactive materials are not the cause of such an excess.



[[Page 25]]



    (4) The plan(s) for remedial action will specify how applicable 

requirements of subpart B would be satisfied. The plan should include 

the schedule and steps necessary to complete the cleanup of groundwater 

at the site. It should document the extent of contamination due to 

releases prior to final disposal, including the identification and 

location of listed constituents and the rate and direction of movement 

of contaminated groundwater, based upon the monitoring carried out under 

Sec.  192.12(c)(1). In addition, the assessment should consider future 

plume movement, including an evaluation of such processes as attenuation 

and dilution and future contamination from beneath a disposal site. 

Monitoring for assessment and compliance purposes should be sufficient 

to establish the extent and magnitude of contamination, with reasonable 

assurance, through use of a carefully chosen minimal number of sampling 

locations. The location and number of monitoring wells, the frequency 

and duration of monitoring, and the selection of indicator analytes for 

long-term groundwater monitoring, and, more generally, the design and 

operation of the monitoring system, will depend on the potential for 

risk to receptors and upon other factors, including characteristics of 

the subsurface environment, such as velocity of groundwater flow, 

contaminant retardation, time of groundwater or contaminant transit to 

receptors, results of statistical evaluations of data trends, and 

modeling of the dynamics of the groundwater system. All of these factors 

should be incorporated into the design of a site-specific monitoring 

program that will achieve the purpose of the regulations in this subpart 

in the most cost-effective manner. In the case of vicinity properties 

(Sec.  192.01(l)(2)), such assessments will usually not be necessary. 

The Secretary, with the concurrence of the Commission, may consider such 

factors as local geology and amount of contamination present in 

determining criteria to decide when such assessments are needed. In 

cases where Sec.  192.12(c)(2) is invoked, the plan should include a 

monitoring program sufficient to verify projections of plume movement 

and attenuation periodically during the extended cleanup period. 

Finally, the plan should specify details of the method to be used for 

cleanup of groundwater.



[48 FR 602, Jan. 5, 1983, as amended at 60 FR 2867, Jan. 11, 1995]