[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: 40CFR191.12]



[Page 9-10]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 191_ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR MANAGEMENT AND 

DISPOSAL OF SPENT NUCLEAR FUEL, HIGH-LEVEL AND TRANSURANIC RADIOACTIVE 

WASTES--Table of Contents

 

             Subpart B_Environmental Standards for Disposal

 

Sec.  191.12  Definitions.



    Unless otherwise indicated in this subpart, all terms shall have the 

same meaning as in subpart A of this part.

    Accessible environment means: (1) The atmosphere; (2) land surfaces; 

(3) surface waters; (4) oceans; and (5) all of the lithosphere that is 

beyond the controlled area.

    Active institutional control means: (1) Controlling access to a 

disposal site by any means other than passive institutional controls; 

(2) performing maintenance operations or remedial actions at a site, (3) 

controlling or cleaning up releases from a site, or (4) monitoring 

parameters related to disposal system performance.

    Annual committed effective dose means the committed effective dose 

resulting from one-year intake of radionuclides released plus the annual 

effective dose caused by direct radiation from facilities or activities 

subject to subparts B and C of this part.

    Aquifer means an underground geological formation, group of 

formations, or part of a formation that is capable of yielding a 

significant amount of water to a well or spring.

    Barrier means any material or structure that prevents or 

substantially delays movement of water or radionuclides toward the 

accessible environment. For example, a barrier may be a geologic 

structure, a canister, a waste form with physical and chemical 

characteristics that significantly decrease the mobility of 

radionuclides, or a material placed over and around waste, provided that 

the material or structure substantially delays movement of water or 

radionuclides.

    Controlled area means: (1) A surface location, to be identified by 

passive institutional controls, that encompasses no more than 100 square 

kilometers and extends horizontally no more than five kilometers in any 

direction from the outer boundary of the original location of the 

radioactive wastes in a disposal system; and (2) the subsurface 

underlying such a surface location.

    Disposal system means any combination of engineered and natural 

barriers that isolate spent nuclear fuel or radioactive waste after 

disposal.

    Dose equivalent means the product of absorbed dose and appropriate 

factors to account for differences in biological effectiveness due to 

the quality of radiation and its spatial distribution in the body; the 

unit of dose equivalent is the ``rem'' (``sievert'' in SI units).

    Effective dose means the sum over specified tissues of the products 

of the dose equivalent received following an exposure of, or an intake 

of radionuclides into, specified tissues of the body, multiplied by 

appropriate weighting factors. This allows the various tissue-specific 

health risks to be summed into an overall health risk. The method used 

to calculate effective dose is described in appendix B of this part.

    Ground water means water below the land surface in a zone of 

saturation.

    Heavy metal means all uranium, plutonium, or thorium placed into a 

nuclear reactor.

    Implementing agency means:

    (1) The Commission for facilities licensed by the Commission;

    (2) The Agency for those implementation responsibilities for the 

Waste Isolation Pilot Plant, under this part, given to the Agency by the 

Waste Isolation Pilot Plant Land Withdrawal Act (Pub. L. 102-579, 106 

Stat. 4777) which, for the purposes of this part, are:

    (i) Determinations by the Agency that the Waste Isolation Pilot 

Plant is in compliance with subpart A of this part;

    (ii) Issuance of criteria for the certifications of compliance with 

subparts B and C of this part of the Waste Isolation Pilot Plant's 

compliance with subparts B and C of this part;

    (iii) Certifications of compliance with subparts B and C of this 

part of



[[Page 10]]



the Waste Isolation Pilot Plant's compliance with subparts B and C of 

this part;

    (iv) If the initial certification is made, periodic recertification 

of the Waste Isolation Pilot Plant's continued compliance with subparts 

B and C of this part;

    (v) Review and comment on performance assessment reports of the 

Waste Isolation Pilot Plant; and

    (vi) Concurrence by the Agency with the Department's determination 

under Sec.  191.02(i) that certain wastes do not need the degree of 

isolation required by subparts B and C of this part; and

    (3) The Department of Energy for any other disposal facility and all 

other implementation responsibilities for the Waste Isolation Pilot 

Plant, under this part, not given to the Agency.

    International System of Units is the version of the metric system 

which has been established by the International Bureau of Weights and 

Measures and is administered in the United States by the National 

Institute of Standards and Technology. The abbreviation for this system 

is ``SI.''

    Lithosphere means the solid part of the Earth below the surface, 

including any ground water contained within it.

    Passive institutional control means: (1) Permanent markers placed at 

a disposal site, (2) public records and archives, (3) government 

ownership and regulations regarding land or resource use, and (4) other 

methods of preserving knowledge about the location, design, and contents 

of a disposal system.

    Performance assessment means an analysis that: (1) Identifies the 

processes and events that might affect the disposal system; (2) examines 

the effects of these processes and events on the performance of the 

disposal system; and (3) estimates the cumulative releases of 

radionuclides, considering the associated uncertainties, caused by all 

significant processes and events. These estimates shall be incorporated 

into an overall probability distribution of cumulative release to the 

extent practicable.

    Radioactive material means matter composed of or containing 

radionuclides, with radiological half-lives greater than 20 years, 

subject to the Atomic Energy Act of 1954, as amended.

    SI unit means a unit of measure in the International System of 

Units.

    Sievert is the SI unit of effective dose and is equal to 100 rem or 

one joule per kilogram. The abbreviation is ``Sv.''

    Undisturbed performance means the predicted behavior of a disposal 

system, including consideration of the uncertainties in predicted 

behavior, if the disposal system is not disrupted by human intrusion or 

the occurrence of unlikely natural events.

    Waste, as used in this subpart, means any spent nuclear fuel or 

radioactive waste isolated in a disposal system.

    Waste form means the materials comprising the radioactive components 

of waste and any encapsulating or stabilizing matrix.



[50 FR 38084, Sept. 19, 1985, as amended at 58 FR 66414, Dec. 20, 1993]