2854 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 192

[FRL–3510–1]

RIN 2060–AC03

Groundwater Standards for Remedial

Actions at Inactive Uranium

Processing Sites

AGENCY: Environmental Protection

Agency.

ACTION: Final rule.

SUMMARY: The Environmental Protection

Agency is issuing final regulations to

correct and prevent contamination of

groundwater beneath and in the vicinity

of inactive uranium processing sites by

uranium tailings. EPA issued

regulations (40 CFR part 192, subparts

A, B, and C) for cleanup and disposal

of tailings from these sites on January 5,

1983. These new regulations replace

existing provisions at 40 CFR

192.20(a)(2) and (3) that were remanded

by the U.S. Court of Appeals for the

Tenth Circuit on September 3, 1985.

They are promulgated pursuant to

Section 275 of the Atomic Energy Act,

as amended by Section 206 of the

Uranium Mill Tailings Radiation

Control Act of 1978 (Public Law 95–

604).

The regulations apply to tailings at

the 24 locations that qualify for

remedial action under Title I of Public

Law 95–604. They provide that tailings

must be stabilized and controlled in a

manner that permanently eliminates or

minimizes contamination of

groundwater beneath stabilized tailings,

so as to protect human health and the

environment. They also provide for

cleanup of contamination that occurred

before the tailings are stabilized.

EFFECTIVE DATE: February 10, 1995.

ADDRESSES: Background Documents. A

report (‘‘Groundwater Protection

Standards for Inactive Uranium Tailings

Sites, Background Information for Final

Rule,’’ EPA 520/1–88–023) has been

prepared in support of these regulations.

Another report (‘‘Groundwater

Protection Standards for Inactive

Uranium Tailings Sites, Response to

Comments,’’ EPA 520/1–88–055)

contains the detailed responses of the

Environmental Protection Agency to

comments on the standard by the

reviewing public. Single copies of these

documents may be obtained from the

Program Management Office (6601J),

Office of Radiation and Indoor Air, U.S.

Environmental Protection Agency,

Washington, DC 20460; (202) 233–9354.

Docket. Docket Number R–87–01

contains the rulemaking record. The

docket is available for public inspection

between 8 a.m.–4 p.m., weekdays, at

EPA’s Central Docket Section (LE–131),

Room M–1500, 401 M Street SW.,

Washington, DC 20460. A reasonable fee

may be charged for copying.

FOR FURTHER INFORMATION CONTACT:

Allan C.B. Richardson, Criteria and

Standards Division (6602J), Office of

Radiation and Indoor Air, U.S.

Environmental Protection Agency,

Washington, DC 20460; telephone (202)

233–9213.

SUPPLEMENTARY INFORMATION:

I. Introduction

On November 8, 1978, Congress

enacted the Uranium Mill Tailings

Radiation Control Act of 1978

(henceforth called ‘‘UMTRCA’’). In

UMTRCA, Congress found that uranium

mill 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 environment

and to prevent or minimize other

environmental hazards from such

tailings.’’ The Act directs the

Administrator of the Environmental

Protection Agency (EPA) to set ‘‘* * *

standards of general application for the

protection of the public health, safety,

and the environment * * *’’ to govern

this process of stabilization, disposal,

and control.

UMTRCA directs the Department of

Energy (DOE) to conduct such remedial

actions at the inactive uranium

processing sites as will insure

compliance with the standards

established by EPA. This remedial

action is to be selected and performed

with the concurrence of the Nuclear

Regulatory Commission (NRC). Upon

completion of the remedial action

program, the depository sites will

remain in the custody of the Federal

government under an NRC license.

The standards apply to residual

radioactive material at the 24 processing

sites designated, as provided in the Act,

by DOE. Residual radioactive material is

defined as any wastes which DOE

determine to be radioactive, either in

the form of tailings resulting from the

processing of ores for the extraction of

uranium and other valuable constituents

of the ores, or in other forms which

relate to such processing, such as

sludges and captured contaminated

water from these sites. (Additional

wastes that do not meet this definition

may be subject to regulation as

hazardous waste under the Solid Waste

Disposal Act (SWDA) as amended by

the Resource Conservation and

Recovery Act of 1976 (RCRA).)

Standards are required for two types

of remedial actions: disposal and

cleanup of residual radioactive material.

Disposal is here used to mean the

operation that places tailings in a

permanent condition which will

minimize risk of harmful effects to the

health of people and harm to the

environment. Cleanup is the operation

that eliminates, or reduces to acceptable

levels, the potential health and

environmental consequences of tailings

or their constituents that have been

dispersed from tailings piles or disposal

areas by natural forces or by human

activity, through removal of residual

radioactive materials from land,

buildings, and groundwater.

On January 5, 1983, EPA promulgated

final standards for the disposal and

cleanup of the inactive mill tailings sites

under UMTRCA (48 FR 590). These

standards were challenged in the Tenth

Circuit Court of Appeals by several

parties (Case Nos. 83–1014, 83–1041,

83–1206, and 83–1300). On September

3, 1985, the court dismissed all

challenges except one: it set aside the

groundwater provisions of the

regulations at 40 CFR 192.20(a)(2) and

(3) and remanded them to EPA ‘‘* * *

to treat these toxic chemicals that pose

a groundwater risk as it did in the active

mill site regulations.’’ On September 24,

1987, EPA proposed new standards to

replace those remanded. A public

hearing was held in Durango, Colorado,

on October 29, 1987. In response to

requests from several commenters at the

public hearing and a later request by the

American Mining Congress, the public

record for comments on the proposed

standard was not closed until January

29, 1988. With this notice, EPA is

establishing final standards to replace

those set aside.

II. Summary of Background

Information

Beginning in the 1940’s, the U.S.

Government purchased large quantities

of uranium for defense purposes. As a

result, large piles of tailings were

created by the uranium milling

industry. Tailings piles pose a hazard to

public health and the environment

because they contain radioactive and

toxic constituents which emanate radon

to the atmosphere and may leach into

groundwater. Tailings, which are a

sand-like material, have also been

removed from tailings piles in the past

for use in construction and for soil
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2855

conditioning. These uses are

inappropriate, because the radioactive

and toxic constituents of tailings may

elevate indoor radon levels, expose

people to gamma radiation, and leach

into ground and surface waters.

Most of the mills are now inactive and

many of the sites were abandoned.

These abandoned sites are being

remediated under Title I of UMTRCA.

Congress designated 22 specific inactive

sites in Title I of UMTRCA, and the DOE

subsequently added two more. Most

remaining uranium mill tailings sites

are regulated by the NRC or States and

will be reclamated under Title II of

UMTRCA. (DOE also owns one inactive

site at Monticello, Utah, that is not

included under UMTRCA). The Title I

sites are located in the West,

predominantly in arid areas, except for

a single site at Canonsburg,

Pennsylvania. Before disposal

operations began, tailings piles at the

inactive sites ranged in area from 5 to

150 acres and in height from only a few

feet to as much as 230 feet. The amount

at each site ranges from residual

contamination to 2.7 million tons of

tailings. The 24 designated Title I sites

combined contain about 26 million tons

of tailings covering a total of about 1000

acres.

Under the provisions of Title I of

UMTRCA, the DOE is responsible for

the disposal of tailings at these sites,

which will then be licensed to DOE by

NRC for long term surveillance and

maintenance, following NRC approval

of the remediation. In addition, tailings

that were dispersed from the piles by

natural forces or that have been

removed for use in or around buildings

or on land are being retrieved and

replaced on the tailings piles prior to

their disposal.

UMTRCA, as originally enacted,

required that DOE complete all these

remedial actions within 7 years of the

effective date of EPA’s standards, that is,

by March 5, 1990. At the end of 1993

disposal actions had been completed at

ten sites: Canonsburg, Pennsylvania,

one of two sites in areas of high

precipitation (Falls City, Texas is the

other); Shiprock, New Mexico; Salt Lake

City, Utah; Lakeview, Oregon; Green

River, Utah; Spook and Riverton,

Wyoming; Lowman, Idaho; Tuba City,

Arizona; and Durango, Colorado.

Disposal actions were well advanced at

eight other sites: Rifle (two piles), Grand

Junction, and Gunnison, Colorado;

Monument Valley, Arizona; Mexican

Hat, Utah; Falls City, Texas; and

Ambrosia Lake, New Mexico. The

remaining sites are in the advanced

stages of planning and should be under

construction within the next two years.

In view of the rate of progress with

remedial work, Congress in 1988

extended the completion date for

disposal and most cleanup activities

until September 30, 1994, and provided

further ‘‘* * * that the authority of the

Secretary to perform groundwater

restoration activities under this title is

without limitation.’’ (Uranium Mill

Tailings Remedial Action Amendments

Act of 1988, P.L. 100–616, November 5,

1988; 42 U.S.C. 7916). Section 1031 of

the Energy Policy Act of 1992 further

extended the completion date for

UMTRCA surface stabilization

(disposal) activities to September 30,

1996.

The most important hazardous

constituent of uranium mill tailings is

radium, which is radioactive. Other

potentially hazardous substances in

tailings piles include arsenic,

molybdenum, selenium, uranium, and,

usually in lesser amounts, a variety of

other toxic substances. The

concentrations of these materials in

tailings vary from pile to pile, ranging

from 2 to more than 100 times local

background soil concentrations. A

variety of organics is also known to have

been used at these sites.

Exposure to radioactive and toxic

substances may cause cancer and other

diseases, as well as genetic damage and

teratogenic effects. Tailings pose a risk

to health because: (1) Radium in tailings

decays into radon, a gaseous radioactive

element which is easily transported in

air and the radioactive decay products

of which may lodge in the lungs; (2)

individuals may be directly exposed to

gamma radiation from the radioactivity

in tailings; and (3) radioactive and toxic

substances from tailings may leach into

water and then be ingested with food or

water, or inhaled following aeration. It

is the last of these hazards that is

primarily addressed here. (Although

radon from radium in groundwater is

unlikely to pose a substantial hazard at

these locations, these standards also

address that potential hazard.) The other

hazards are covered by existing

provisions of 40 CFR part 192.

EPA’s technical analysis was based on

detailed reports for 14 of the 24 inactive

uranium mill tailings sites that had been

developed by late 1988 for the

Department of Energy by its contractors.

Preliminary data for the balance of the

sites were also examined. Those data

showed that the volumes of

contaminated water in aquifers at the 24

sites range from a few tens of millions

of gallons to 4 billion gallons. In a few

instances mill effluent was apparently

the sole source of this groundwater.

Each of the 14 sites examined in detail

had at least some groundwater

contamination beneath and/or beyond

the site. In some cases the groundwater

upgradient of the pile already exceeded

EPA drinking water standards for one or

more contaminants due to

mineralization sources or due to

anthropogenic sources other than the

uranium milling activities, thus making

it unsuitable for use as drinking water

without treatment and, in some extreme

cases, for most other purposes before it

was contaminated by effluent from the

mill. Some contaminants from the

tailings piles are moving offsite quickly

and others are moving slowly. The time

for natural flushing of the contaminated

portions of these aquifers was estimated

to vary from a couple of years to many

hundreds of years. Active restoration

was estimated to take from less than 5

years at most sites to approximately 50

years at one site.

DOE currently estimates that there is

approximately 4.7 billion gallons of

contaminated water, but this estimate

does not include all sites. One site,

Lowman, Idaho, shows no sign of

contamination related to the processing

activities, while the site with the largest

amount of contamination, Monument

Valley, Arizona, has an estimated 0.75

billion gallons of contaminated water.

The DOE estimate does not include

those sites where current assessments

indicate that supplemental standards

should be applied, because

contamination at these sites has been

hard to quantify.

Contaminants that have been

identified in the groundwater

downgradient from a majority of the

sites include uranium, sulfate, iron,

manganese, nitrate, chloride,

molybdenum, selenium, and total

dissolved solids. Radium, arsenic,

fluoride, sulfide, chromium, cadmium,

vanadium, lead, and copper have also

been found in the groundwater at one or

more sites.

UMTRCA requires that the standards

established under Title I provide

protection that is consistent, to the

maximum extent practicable, with the

requirements of RCRA. In this regard,

regulations established by EPA for

hazardous waste disposal sites under

RCRA provide for the specification of a

groundwater protection standard for

each waste management area in the

facility permit (see 40 CFR part 264,

subpart F). The groundwater protection

standard includes a list of specific

hazardous constituents relevant to each

waste management area, a concentration

limit for each hazardous constituent, the

point of compliance, and the

compliance period. The subpart F

regulations specify that the

concentration limits may be set at
2856 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

general numerical limits (maximum

concentration limits (MCLs)) for some

hazardous constituents or at their

background level in groundwater unless

alternate concentration limits (ACLs) are

requested and approved. ACLs may be

requested based upon data which would

support a determination that, if the ACL

is satisfied, the constituent would not

present a current or potential threat to

human health and the environment.

This standard incorporates many of

these provisions into the regulations for

the Title I sites.

III. Changes and Clarifications in

Response to Comments

These final standards modify and

clarify some of the provisions of the

proposed standards as a result of

information and views submitted during

the comment period and at the public

hearing. EPA received many comments

on the proposed standards. Twentythree letters were received and eight

individuals testified at the public

hearing. Comments were submitted

from private citizens, public interest

groups, members of the scientific

community, and representatives of

industry and of State and Federal

agencies. EPA has carefully reviewed

and considered these comments in

preparing its detailed Response to

Comments and the final Background

Information Document and in

developing the final standards. EPA’s

responses to major comments are

summarized below.

Uranium Concentration Limit

Several commenters pointed out that

the Agency used inappropriate dose

conversion values (nonstochastic) for

uranium and radium (instead of the

more appropriate stochastic values) in

developing the proposed concentration

limit for uranium. These comments

were correct. We have reevaluated the

risks associated with ingestion of

uranium, using current risk factors for

radiocarcinogenicity of uranium, and

have also considered the chemical

toxicity of uranium. We have concluded

that the level proposed, 30 pCi/liter,

provides an adequate margin of safety

against both carcinogenic and toxic

effects of uranium, and that the level

should be expressed in terms of the

concentration of radioactivity, because

it is related to the principal health risk,

and can accommodate different levels of

radioactive disequilibrium between

uranium-234 and uranium-238.

EPA’s Office of Groundwater and

Drinking Water has also examined these

factors, and, on July 18, 1991, proposed

the MCL for uranium in drinking water

be set at a chemical concentration

comparable to the limit on radioactivity

promulgated in this regulation. Should

the MCL for drinking water, as finally

promulgated, provide a level of health

protection different from that provided

by the limit in this regulation, EPA will

reconsider the limit at that time. On the

basis of the above considerations, the

limit for uranium has been established

at 30 pCi/liter for this regulation.

Molybdenum Concentration Limit

Several reviewers objected to the

proposed inclusion of a limit on

molybdenum. They pointed out that

EPA has not established a drinking

water standard for this element. While

this is true, the drinking water

regulations also make provision for

health advisories in the case of

contaminants that are problems only in

special situations. Molybdenum in the

vicinity of uranium mill tailings is such

a special case. Uranium mill tailings

often contain high concentrations of

molybdenum that can leach into

groundwater in concentrations that may

cause toxic effects in humans and cattle.

This rule therefore continues to contain

a limit on the concentration of

molybdenum in groundwater. The value

chosen remains the same as that

proposed, as discussed in Section IV

below.

Other Groundwater Limits

These groundwater limits incorporate

MCLs issued under the Safe Drinking

Water Act (SDWA) (42 USC 300f, et

seq.) and in effect for sites regulated

under RCRA from the time these limits

were proposed on September 24, 1987,

to the present. However, on January 30,

1991, EPA issued new MCLs for some

of the inorganic constituents included

in the present limits, and proposed new

drinking water standards for radioactive

constituents were published on July 18,

1991 (56 FR 3526 and 33050). Following

publication of final drinking water

standards for radioactive constituents,

EPA will consider whether the benefits

and costs implied by differences

between these limits and the new

drinking water standards warrant

proposing to incorporate the new values

into both the Title I and the Title II

limits for groundwater.

Application of These Regulations to

Vicinity Properties

Several commenters questioned the

wisdom of applying these regulations to

vicinity properties. (Vicinity properties

are real properties or improvements in

the vicinity of a tailings pile that are

determined by DOE, in consultation

with the NRC, to be contaminated with

residual radioactive materials.) They

indicated that if the portion of the

proposed rule requiring detailed

assessment and monitoring were

applied to all vicinity properties, it

would greatly expand the cost of the

program without providing additional

benefits. Since only a few vicinity

properties contain sufficient tailings to

constitute a significant threat of

groundwater contamination, we have

concluded that detailed assessment and

monitoring, followed by identification

of listed constituents and groundwater

standards, is not required at all vicinity

properties. It is necessary only at those

vicinity properties with a significant

potential for groundwater

contamination, as determined by the

DOE (with the concurrence of NRC)

using factors such as those in EPA’s

RCRA Facility Assessment Guidance

document. It should be noted that this

modification applies to the requirement

for detailed assessment and monitoring

only; the standards for cleanup of

groundwater contamination are not

changed. In addition, we note that the

minimal quantities of residual

radioactive materials left behind at

vicinity properties after compliance

with subpart B do not constitute

disposal sites under subpart A.

Application of State Regulations to

These Sites

Some commenters expressed the view

that these regulations should require

consistency with State laws and

regulations. EPA’s regulations for

licensed mill tailings sites under Title II

of this Act do not contain such a

provision. (Although NRC Agreement

States may, under the Atomic Energy

Act, adopt standards which ‘‘* * * are

equivalent to the extent practicable or

more stringent * * *,’’ they have not

done so under UMTRCA.) We have

decided that decisions regarding

consistency with State laws and

regulations should be made by DOE in

consultation with the States, as

provided by Section 103 of the Act. In

making these decisions in cases where

an approved Wellhead Protection Area,

under the Safe Drinking Water Act, is

associated with the site, however, DOE

must comply with the provisions of that

program, unless an exemption is granted

by the President of the United States. In

addition, contamination on the site that

is not covered by UMTRCA (because it

is not related to the processing

operation) may be covered by Federal or

State RCRA programs.

Application of Institutional Controls

During an Extended Remedial Period

Several comments were received

concerning the effectiveness, reliability,
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2857

and enforceability of institutional

controls to be applied during a remedial

period that has been extended to take

advantage of natural flushing. EPA

recognizes that some institutional

controls, such as advisories or signs,

although desirable as secondary

measures, are not appropriate as

primary measures for preventing human

exposure to contaminated water. For

this reason, the regulations permit

institutional controls to be used in place

of remediation only when DOE is able

to ensure their effectiveness will be

maintained during their use. The

standards require that institutional

controls ‘‘* * * effectively protect

public health and the environment and

satisfy beneficial uses of

groundwater * * *’’ during their

period of application. In this regard, we

note that tribal, state, and local

governments can also play a key role in

assuring the effectiveness of

institutional controls. In some cases this

may be effected through changes in

tribal, state, or local laws to ensure the

enforceability of institutional controls

by the administrative or judicial

branches of government entities. One

State indicated that some institutional

controls, such as deed restrictions,

should not be viewed as restrictions

since they do not empower any agency

to prohibit access to contaminated

water. However, judicial enforcement of

deed restrictions can be as effective as

administrative enforcement of other

institutional controls by a government

agency. Therefore, deed restrictions are

an acceptable institutional control if

they are enforceable by a court with

jurisdiction over the site at which they

are used, and if the implementing

agency will take appropriate steps to

assure their effective application.

Some commenters expressed the view

that, if institutional controls are used,

this use must be restricted to the 7-year

period for remediation authorized in

Section 112(a) of UMTRCA. EPA

believes that it is not possible to achieve

cleanup of groundwater at all of the

sites within 7 years, no matter what

reclamation scheme is employed. It is

therefore necessary to consider time

frames other than that originally

contemplated in UMTRCA for

completion of remedial actions.

Congress, in granting an extension of the

authorization in Section 112(a) of

UMTRCA for disposal and cleanup

actions from March 5, 1990 to

September 30, 1994, provided further

‘‘* * * that the authority of the

Secretary to perform groundwater

restoration activities under this title is

without limitation.’’ (Uranium Mill

Tailings Remedial Action Amendments

Act of 1988 (42 U.S.C. 7916)). In

addition, under Section 104(f)(2) of the

Act (42 U.S.C. 7919(f)(2)), the NRC may

require maintenance of corrective and

institutional measures that are already

in place at the time authorization under

Section 112(a) expires, without time

limitation.

The provisions for use of natural

flushing when appropriate institutional

controls are in place are consistent with

existing regulations under Title II,

although they are not explicit in those

regulations. In cases where groundwater

contamination is detected, the Title II

regulations specify when corrective

actions must begin, but do not specify

a time when corrective actions must be

completed. These provisions under Title

I provide additional guidance on the

length of time over which institutional

control may reasonably be relied upon,

and further guidance on the kinds of

institutional provisions that would be

appropriate at any uranium tailings site.

In addition, use of institutional controls

is not limited to extended remedial

periods. Interim institutional controls

may also be used to protect public

health or the environment, when DOE

finds them necessary and appropriate,

prior to commencing active remedial

action, during active remedial action, or

during implementation of other

compliance strategies.

Other comments addressed a variety

of matters, including the monitoring of

institutional controls, the relationship

between long-term maintenance

responsibilities and the 100-year limit

on use of institutional controls, types of

institutional controls, longer or shorter

extended remedial periods, and the

legality of institutional controls under

UMTRCA. These matters are addressed

in the Response to Comments,

published separately as a background

document.

Point of Compliance

Several commenters objected to the

definition of the point of compliance in

the disposal standards (subpart A), and

suggested that it be defined at some

finite distance from the edge of the

remediated tailings instead of at the

downgradient edge of the pile, as in

regulations established under RCRA.

They indicated that the remediated

tailings may seep a minor amount of

contamination, which may cause the

standards to be exceeded at the

proposed point of compliance, under

conditions where there would be no

detriment to human health or the

environment at small distances away.

This difficulty can be solved, as

proposed, by moving the point of

compliance or, alternatively, by granting

an ACL if it can be shown that such

levels of contamination will not impair

human health or damage the

environment. We have concluded the

latter is more in keeping with the

regulations established under RCRA.

The standards provide that DOE may

request an ACL under such

circumstances and NRC may approve

such a request if contamination of

groundwater will not endanger human

health or degrade the environment. It is

our view that this requirement would

usually be satisfied at any site where the

minor seepage noted above is not

projected to extend beyond a few

hundred meters from the waste

management area and will not extend

outside the site boundary. This could

occur under a variety of circumstances

where important roles are played by

attenuation, dilution, or by vapor

transport in unsaturated zones.

Under the cleanup standard (subpart

B), the DOE is required to characterize

the extent of contamination from the

site and clean it up wherever it exceeds

the standards. This characterization and

confirmation of cleanup will be carried

out through the monitoring program

established under § 192.12(c)(3).

Although the DOE is not required to

clean up preexisting contamination that

is located beneath a remediated tailings

pile, they are required to consider this

contamination when developing their

plan(s) for remedial action and will

have to clean up any contamination that

will migrate from beneath the pile and

exceed the concentration limits

established in accordance with

§ 192.02(c)(3).

Alternate Concentration Limits

Several reviewers commented that

EPA should not, for a variety of reasons,

delegate the responsibility for approving

ACLs to the NRC. Others stated that the

standards were so strict that ACLs

would be needed at every site. EPA

considered a number of approaches to

the provision for granting ACLs. These

included deleting the ACL provision,

establishing (by regulation) generic

criteria for ACLs to be implemented by

NRC, providing for some form of EPA

review or oversight of ACL

implementation, and (as in the proposed

regulation) providing for no EPA role in

setting ACLs at individual sites.

EPA has decided not to delete the

ACL provision because it is clearly

needed, if for no other reason than to

deal with the possibilities of

unavoidable minor projected seepage

over the extremely long-term design life

(1000 years) of the disposal required, in

most cases, by these standards, and of
2858 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

cleanup situations involving pollutants

for which no MCLs exist. Establishment

of a complete set of regulations

specifying generic criteria for granting

ACLs presents difficulties for

rulemaking, since ACL determinations

often involve complex judgments that

are not amenable to being reduced to

simple regulatory requirements. In this

regard we note that such regulations do

not yet exist in final form for sites

directly regulated under RCRA.

However, the Agency has issued interim

final Alternate Concentration Limit

Guidance (OSWER Directive 9481.00;

EPA/SW–87–017), and has proposed

several relevant rules, e.g., under 40

CFR parts 264, 265, 270, and 271, for

Corrective Action for Solid Waste

Management Units at Hazardous Waste

Management Facilities (55 FR 30798;

July 27, 1990). In addition, the NRC

proposed a draft Technical Position on

Alternate Concentration Limits for

Uranium Mills at Title II sites on March

21, 1994 (59 FR 13345). EPA has

reviewed the NRC draft Technical

position, and we find that it is

consistent, in general, with EPA’s own

guidance and proposed rules. The NRC

draft position does not, however,

specify an upper limit on risks to

humans from carcinogens. We have

reconsidered the issue of EPA review or

oversight of ACLs at Title I sites in light

of this review, and concluded that, in

the interests of assuring that public

health is adequately protected while at

the same time minimizing the regulatory

burden on DOE, the best course of

action is to specify that upper limit in

this regulation and assign the

responsibility for making

determinations for ACLs at individual

sites to NRC. Accordingly, in this rule,

in the implementing guidance contained

in subpart C, § 192.20(a)(2), we now

specify that the criterion for known or

suspected carcinogens contained in the

above-referenced RCRA documents

should be applied in granting ACLs.

That criterion specifies that ACLs

should be established at levels which

represent an excess lifetime risk, at a

point of exposure, no greater than 10¥4

to 10¥6 to an average individual.

EPA is required by UMTRCA (Section

206) to be consistent, to the maximum

extent practicable, with RCRA. For this

reason, relevant portions of the RCRA

regulations have been incorporated. For

example, these regulations provide for

the use of ACLs when it can be shown

that the criteria specified in

§ 192.02(c)(3)(ii) are satisfied. It remains

the view of the Agency that, as at the

Title II sites, an ACL is appropriate if

the NRC has determined that these

criteria are satisfied when the otherwise

applicable standard will be met within

the site boundary (or at a distance of 500

meters, if this is closer). It is clear that

ACLs will usually be appropriate to

accommodate the controlled minor

seepage anticipated from properly

designed tailings disposal within such

distances, when public use is not

possible.

Cost

Greater consideration of cost and costbenefit analysis was requested by

several commenters. In 1983, Congress

amended UMTRCA to provide that

when establishing standards the

Administrator should consider, among

other factors, the economic costs of

compliance. We have considered these

costs in two ways. First, we compared

them to the benefit, expressed in terms

of the value of the product—processed

uranium ore—which has led to

contamination of groundwater at these

sites. We estimate the present value of

the processed uranium ore from these

sites as approximately 3.9 billion dollars

(1989 dollars). The estimated cost of

compliance is approximately 5.5% of

this value, and we judge this to be a not

unreasonable incremental cost for the

remediation of contamination from the

operations which produced this

uranium. As a second way of

considering the economic costs of

compliance, we examined the cost of

alternative ways to supply the resources

for future use represented by these

groundwaters. As noted earlier, water is

a scarce resource in the Western States

where this cleanup would occur. When

other resources have been exhausted,

the only remaining alternative to

cleaning up groundwater in the vicinity

of these sites is to replace this water by

transporting water from the nearest

alternative source. Our analysis of the

costs of doing this indicates that it is

significantly more costly to supply

water from alternative sources than it

would be to clean up the groundwater

at these sites. We have concluded,

therefore, that this final rule involves a

reasonable relationship between the

overall costs and benefits of compliance.

The RCRA subpart F regulations do

not include cost as a consideration for

the degree of cleanup of groundwater,

and these regulations also do not

provide for site-specific standards based

on site-specific costs. Nonetheless, it is

clearly desirable and appropriate to

apply the most cost-effective remedies

available to meet these standards at each

site, and we anticipate that DOE will

make such choices in choosing the

remedies it applies to satisfy these

standards. Further, once the basic

criteria for establishing ACLs set forth in

§ 192.02(c)(3)(ii)(B) have been satisfied,

if a higher level of protection is

reasonably achievable, this should be

carried out. However, we do not believe

it is appropriate to apply detailed cost/

benefit balancing judgments to justify

lesser levels of protection for ground

water. The benefits of cleaning up

groundwater are often not quantifiable

and may not become known for many

years; therefore, site-specific costbenefit analyses are difficult to apply in

such situations. Moreover, Congress

provided no authority that protection of

ground water at each site should be

limited by cost/benefit considerations,

even after reconsidering the question in

the 1984 amendments.

Some reviewers raised the issue of

additional costs arising from use of

these standards in other applications,

such as CERCLA cleanups. We

recognize that there may be costs

associated with using these standards as

precedents for other waste cleanup

projects. However, the reasonableness of

incurring such costs should be assessed

when it is possible to do so with

complete information, that is, at the

time of application of these standards as

precedents for situations other than the

one for which they were developed.

Natural Restoration

The use of natural restoration of an

aquifer was discussed by several

reviewers. Some felt that it was a viable

and desirable alternative, because it is

easy and inexpensive to apply, for

groundwaters that are not expected to be

used for drinking or other purposes

during the cleanup period. Others felt

that it should be prohibited because it

required a reliance on institutional

controls and would circumvent active

cleanup of groundwater. EPA believes

that the use of natural restoration can be

a viable alternative in situations where

water use and ecological considerations

are not affected, and cleanup will occur

within a reasonable time. We have

concluded that institutional controls,

when enforced by government entities,

or that otherwise have a high degree of

permanence, can be relied on for

periods of time up to 100 years, and that

adequate safeguards are provided

through NRC oversight of the

implementation of these standards to

prevent this alternative from being used

to circumvent active cleanup of water

that will be used by nearby populations.

Commenters suggested that natural

restoration was not adequate to restore

water quality at these sites. DOE has

indicated that they expect that natural

restoration may be all that is necessary

at up to eight sites and could be used
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2859

in conjunction with active remedial

measures at several other sites. Natural

restoration is most valuable when the

contaminated aquifer discharges into a

surface water body that will not be

adversely affected by the contamination.

Pile and Liner Design

The design of the remediated pile and

the use of a liner was of concern to

several commenters, and

recommendations were given for

suitable designs. These commenters

feared that water would continually

infiltrate the remediated piles and

contaminate groundwater.

These EPA standards would not be

satisfied by designs which allow

contamination that would adversely

affect human health or the environment.

Further, current engineering designs for

covers incorporate a number of features

that control infiltration to extremely low

levels. These may include an erosion

barrier (with vegetation, where feasible)

to transpire moisture and reduce

infiltration; rock filters and drains to

drain and laterally disperse any

episodic infiltration; very low

permeability infiltration barriers to

intercept residual infiltration; and

finally, the thick radon barrier, which

further inhibits infiltration. The

combined effect of these features is to

reduce the overall hydrological

transmission of covers to levels on the

order of one part in a billion, with a

resulting high probability that there will

be no saturated zone of leachate in or

below the tailings. EPA expects DOE to

use such state-of-the-art designs

wherever it is appropriate to do so

because of the proximity of

groundwater.

Under the provisions of UMTRCA, the

detailed design of the pile and its cover

is the responsibility of DOE, and

confirmation of the viability of the

design to satisfy EPA’s standards is the

responsibility of NRC. EPA’s

responsibility is to promulgate the

standards to which the disposal must

conform. It would be inconsistent with

the division of responsibilities set forth

in UMTRCA to specify actual designs

for the piles in these regulations. In this

connection, the requirement to provide

a liner when tailings are moved to a new

location in a wet state is properly seen

as a generic management requirement.

Any liner for this purpose would only

serve a useful purpose for the relatively

short time over which the moisture

content of the pile adjusts to its longterm equilibrium value, after which the

cover design would determine the

groundwater protection capability of the

disposal.

Restricted List of Constituents

Commenters were overwhelmingly

opposed to a restricted list of

radioactive or toxic constituents and

recommended that the entire list of

constituents be relied upon. It is the

Agency’s experience that, under RCRA,

no changes in this list have been

requested based on the criteria provided

in § 264.93(b). These criteria allow for

hazardous constituents to be excluded

based on a determination that the

constituent does not pose a substantial

present or potential hazard to human

health or the environment. Therefore,

that portion of the RCRA standards

which specify conditions for the

exclusion of constituents from the

RCRA list of hazardous constituents has

been excluded as unnecessary.

However, a short list of compounds

has been developed by EPA for use in

monitoring groundwater under RCRA.

This rule incorporates that list of

constituents (Appendix IX of part 264)

in place of the complete list in

Appendix I for the monitoring programs

required at §§ 192.02(c)(1), 192.03, and

192.12(c)(1). However, the rule still

requires that all hazardous constituents

listed in Appendix I be considered

when corrective action is necessary.

IV. Summary of the Final Standard

These final standards consist of three

parts: a first part governing protection

against future groundwater

contamination from tailings piles after

disposal; a second part that applies to

the cleanup of contamination that

occurred before disposal of the tailings

piles; and a third part that provides

guidance on implementation and

specifies conditions under which

supplemental standards may be applied.

A. The Groundwater Standard for

Disposal

The standard for protection of

groundwater after disposal (subpart A)

is divided into two parts that separately

address actions to be carried out during

periods of time designated as the

disposal and post-disposal periods. The

disposal and post-disposal periods are

defined in a manner analogous to the

closure and post-closure periods,

respectively, in RCRA regulations.

However, there are some differences

regarding their duration and the timing

of any corrective actions that may

become necessary due to failure of

disposal systems to perform as

designed. (Because there are no mineral

processing activities currently at these

inactive sites, standards are not needed

for an operational period.) The disposal

period, for the purpose of this

regulation, is defined as that period of

time beginning on the effective date of

the original Title I part 192 standard for

the inactive sites (March 7, 1983) and

ending with completion of all actions

related to disposal except post-disposal

monitoring and any corrective actions

that might become needed as a result of

failure of completed disposal. The postdisposal period begins with completion

of disposal actions and ends after an

appropriate period for the monitoring of

groundwater to confirm the adequacy of

the disposal. The groundwater standard

governing the actions to be carried out

during the disposal period incorporates

relevant requirements from subpart F of

part 264 of this chapter (§§ 264.92–

264.95). The standard for the postdisposal period reflects relevant

requirements of § 264.111 of this

Chapter. The disposal standard also

includes provisions for monitoring and

any necessary corrective action during

both disposal and post-disposal periods.

These provisions are essentially the

same as those governing the licensed

(Title II) uranium mill tailings sites (40

CFR 192, subparts D and E; see also the

Federal Register notices for those

standards published on April 29, 1983

and on October 7, 1983). Several

additional constituents are regulated,

however, in these final Title I

regulations.

These regulations do not change

existing requirements at Title I sites for

the period of time disposal must be

designed to comply with the standards,

and therefore remain identical to the

requirements for licensed (Title II) sites

in this respect. The Agency also recently

promulgated final regulations for spent

nuclear fuel, and high level and

transuranic radioactive wastes (40 CFR

part 191; 58 FR 66398, December 20,

1993). Those standards specify a

different design period for compliance

(10,000 years versus 1000 years) for two

principle reasons: (1) The level of

radioactivity, and therefore the level of

health risk, in the wastes addressed

under 40 CFR part 191 is many orders

of magnitude greater than those

addressed here. (The radioactivity of

tailings is typically 0.4 to 1.0 nCi/g, 40

CFR part 191 wastes are always greater

than 100 nCi/g, and are typically far

higher.) (2) The volume of uranium mill

tailings is far greater than the waste

volumes addressed under 40 CFR part

191. The containment that would be

required to meet a 10,000 year

requirement is simply not feasible for

the volumes of tailings involved (the

option of underground disposal was

addressed and rejected in the original
2860 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

rulemakings for the Title I and Title II

sites).

These regulations require installation

of monitoring systems upgradient of the

point of compliance (i.e., in the

uppermost aquifer upgradient of the

edge of the tailings disposal site) or at

some other point adequate to determine

background levels of any listed

constituents that occur naturally at the

site. The disposal should be designed to

control, to the extent reasonably

achievable for 1000 years and, in any

case, for at least 200 years, all listed

constituents identified in residual

radioactive materials at the site to levels

for each constituent derived in

accordance with § 192.02(c)(3).

Accordingly, the elements of the

groundwater protection standard to be

specified for each disposal site include

a list of relevant constituents, the

concentration limits for each such

constituent, and the compliance point.

These standards provide for

consideration of ACLs if the disposal

cannot reasonably be designed to assure

conformance to background levels (or

those in Table 1) over the required term.

ACLs can be granted provided that, after

considering practicable corrective

actions, a determination can be made

that it satisfies the values given by

implementing the conditions for ACLs

under § 192.02(c)(3)(ii).

The standards for Title II sites require

use of a liner under new tailings piles

or lateral extensions of existing piles.

These standards for remedial action at

the inactive Title I sites do not contain

a similar provision. EPA assumes that

the inactive piles will not need to be

enlarged. Several, however, will be

relocated. However, unlike tailings at

the Title II sites, which generally may

contain large amounts of process water,

the inactive tailings contain little or no

free water. Such tailings, if properly

located and stabilized with a cover

adequate to ensure an unsaturated zone,

are not likely to require a liner in order

to protect groundwater.

However, a liner would be needed for

an initial drying-out period to meet

these groundwater standards if a

situation arose where the tailings

initially contained water above the level

of specific retention. For example,

tailings to which water was added to

facilitate their removal to a new site

(i.e., through slurrying), or for

compaction during disposal. (It is

anticipated that piles will never be

moved to areas of high precipitation or

situated within a zone of water table

fluctuation.) Section 192.20(a)(3)

requires the remedial plan to address

how any such excess water in tailings

would be dealt with. In such

circumstances it will normally be

necessary to use a liner or equivalent to

assure that groundwater will not be

contaminated while the moisture level

in the tailings adjusts to its long-term

equilibrium value. Currently, however,

DOE plans do not include slurrying any

tailings to move them to new locations.

Further, for all but two sites, of which

one has already been closed

(Canonsburg) and at the other (Falls

City) disposal actions are well

advanced, the tailings are located in arid

areas where annual precipitation is low.

Disposal designs which prevent

migration of listed constituents in the

groundwater for only a short period of

time would not provide appropriate

protection. Such approaches simply

defer adverse groundwater effects.

Therefore, measures which only modify

the gradient in an aquifer or create

barriers (e.g., slurry walls) would not of

themselves provide an adequate

disposal.

Section 192.02(d) requires that a site

be closed in a manner that minimizes

further maintenance. Depending on the

physical properties of the sites,

candidate disposal systems, and the

effects of natural processes over time,

measures required to satisfy these

standards will vary from site to site.

Actual site data, computational models,

and prevalent expert judgment may be

used in deciding that proposed

measures will satisfy the standards.

Under the provisions of Section 108(a)

of UMTRCA, the adequacy of these

judgments is determined by the NRC.

For the post-disposal period, a

groundwater monitoring plan is

required to be developed and

implemented. The plan will require

monitoring for a period of time deemed

sufficient to verify, with reasonable

assurance, the adequacy of the disposal

to achieve its design objectives for

containment of listed constituents. EPA

expects this period of time to be

comparable, in most cases, to that

required under § 264.117 of Title 40 for

waste sites regulated under RCRA (i.e.,

a few decades). However, there may be

situations where longer or shorter

periods are appropriate. Installation and

commencement of the monitoring

required under § 192.03 will satisfy this

EPA standard, for the purposes of

licensing of the site by the NRC.

With regard to this monitoring,

UMTRCA provides that, after

remediation is completed and custody is

transferred to a Federal agency, NRC

may require that the Federal agency

having custody of each remediated

tailings site ‘‘* * * undertake such

monitoring, maintenance, and

emergency measures * * *and other

actions as [NRC] deems necessary to

comply with [EPA’s standards]’’

(UMTRCA, Section 104(f)(2)). Although

it is not intended that routine

monitoring be carried out as a

requirement for conformance to these

standards for the 200- to 1000-year

period over which the disposal is

designed to be effective, NRC may

require more extensive monitoring to

comply with EPA’s standards, as NRC

deems necessary under § 104(f)(2) of the

Act.

During the post-disposal period, if

listed constituents from a disposal site

are detected in excess of the

groundwater standards, these

regulations require a corrective action

program designed to bring the disposal

and the groundwater into compliance

with the provisions of § 192.02(c)(3) and

subpart B, respectively. In designing

such a corrective action program, the

implementing agencies may consider all

of the provisions available under

subparts A, B, and C. A modification of

the monitoring program sufficient to

demonstrate that the corrective

measures will be successful is also

required. In designing future corrective

action programs, the implementing

agencies may also wish to consider the

guidance provided by new regulations

now being developed for the RCRA

program that will be proposed as

subpart S to Title 40. However, the

requirements of Part 192 will still

govern regulatory determinations of

acceptability.

Additional Regulated Constituents

For the purpose of this regulation

only, the Agency is regulating, in

addition to the hazardous constituents

referenced by § 264.93, molybdenum,

nitrate, combined radium-226 and

radium-228, and combined uranium-234

and uranium-238. Molybdenum,

radium, and uranium were addressed by

the Title II standards because these

radioactive and/or toxic constituents are

found in high concentrations at many

mill tailings sites. These regulations add

numerical limits for these constituents.

Nitrate was added because it had been

identified in concentrations far in

excess of drinking water standards in

groundwater at a number of the inactive

sites.

The concentration limit for

molybdenum in groundwater from

uranium tailings is set at 0.1 milligram

per liter. This is the value of the

provisional Adjusted Acceptable Daily

Intake (AADI) for drinking water

developed by EPA under the Safe

Drinking Water Act (50 FR 46958). The

Agency has established neither a

maximum concentration limit goal
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2861

(MCLG) nor a maximum concentration

limit (MCL) for molybdenum because it

occurs only infrequently in water.

According to the most recent relevant

report of the National Academy of

Sciences (Drinking Water and Health,

1980, Vol. III), molybdenum from

drinking water, except for highly

contaminated sources, is not likely to

constitute a significant portion of the

total human intake of this element.

However, as noted above, uranium

tailings are often a highly concentrated

source of molybdenum, and it is

therefore appropriate to include a

standard for molybdenum in this rule.

In addition to the hazard to humans, our

analysis of toxic substances in tailings

in the Final Environmental Impact

Statement for Remedial Action

Standards for Inactive Uranium

Processing Sites (EPA 520/4–82–013–1)

found that, for ruminants, molybdenum

in concentrations greater than 0.05 ppm

in drinking water would lead to chronic

toxicity. This concentration included a

safety factor of 10; the standard provides

for a safety factor of 5, which we

consider adequately protective for

ruminants.

The standard for combined uranium234 and uranium-238 due to

contamination from uranium tailings is

30 pCi per liter. The level of health risk

associated with this standard is

equivalent to the level proposed as the

MCL for uranium in drinking water by

EPA (56 FR 33050, July 18, 1991). The

standard promulgated here applies to

remedial actions for uranium tailings

only. When the Agency has established

a final MCL for isotopes of uranium in

drinking water, we will consider

whether this standard needs to be

reviewed.

The limit for nitrate (as nitrogen) is 10

mg per liter. This is the value of the

drinking water standard for nitrate.

B. The Cleanup Standard

With the exception of the point of

compliance provision, the standard

(subpart B) for cleanup of contaminated

groundwater contains the same basic

provisions as the standard for disposal

in subpart A. In addition, it provides for

the establishment of supplemental

standards under certain conditions, and

for use of institutional control to permit

passive restoration through natural

flushing when no public water system is

involved.

Although the standards specify a

single point of compliance for

conformance to the groundwater

standards for disposal, this does not

suffice for the cleanup of groundwater

that has been contaminated before final

disposal. Instead, in this case

compliance must be achieved anywhere

contamination above the levels

established by these standards is found

or is projected to be found in

groundwater outside the disposal area

and its cover. The standards require

DOE to establish a monitoring program

adequate to determine the extent of

contamination (§ 192.12(c)(1)) in

groundwater around each processing

site. The possible presence of any of the

inorganic or organic hazardous

constituents identified in tailings or

used in the processing operation should

be assessed. The plan for remedial

action referenced under § 192.20(b)(4)

should document the extent of

contamination, the rate and direction of

movement of contaminants, and

consider future movement of the plume.

The cleanup standards normally require

restoration of all contaminated

groundwater to the levels provided for

under § 192.02(c)(3). These levels are

either background concentrations, the

levels specified in Table 1 in the rule,

or ACLs. In cases where the

groundwater is not classified as of

limited use, any ACL should be

determined under the assumption that

the groundwater may be used for

drinking purposes. In certain

circumstances, however, supplemental

standards set at levels that would be

achieved by remedial actions that come

as close to meeting the otherwise

applicable standards as is reasonably

achievable under the circumstances may

be appropriate. Such supplemental

standards and ACLs are distinct

regulatory provisions and may be

considered independently. The

regulations provide that supplemental

standards may be granted if:

• Groundwater at the site is of limited

use (§ 192.11(e)) in the absence of

contamination from residual radioactive

materials; or

• Complete restoration would cause

more environmental harm than it would

prevent; or

• Complete restoration is technically

impracticable from an engineering

perspective.

The use of supplemental standards for

limited use groundwater applies the

groundwater classification system

proposed in EPA’s 1984 Groundwater

Protection Strategy. As proposed for use

in these standards (52 FR 36003,

September 24, 1987), Class III

encompasses groundwaters that are not

a current or potential source of drinking

water because of widespread, ambient

contamination caused by natural or

human-induced conditions, or cannot

provide enough water to meet the needs

of an average household. These

standards adopt the proposed definition

of limited use groundwater. However,

for the purpose of qualifying for

supplemental standards, humaninduced conditions exclude

contributions from residual radioactive

materials.

Water which meets the definition of

limited use groundwater may,

nevertheless, reasonably be or be

projected to be useful for domestic,

agricultural, or industrial purposes. For

example, in some locations higher

quality water may be scarce or absent.

Therefore, § 192.22(d) requires the

implementing agencies to remove any

additional contamination that has been

contributed by residual radioactive

materials to the extent that is necessary

to preserve existing or reasonably

projected beneficial uses in areas of

limited water supplies. At a minimum,

at sites with limited use groundwater,

the supplemental standards require

such management of contamination due

to tailings as is required to assure

protection of human health and the

environment from that contamination.

For example, if the additional

contamination from the tailings would

cause an adverse effect on drinkable

groundwater that has a significant

interconnection with limited use

groundwater over which the tailings

reside, then the additional

contamination from the tailings will

have to be abated.

Supplemental standards are also

appropriate in certain other cases

similar to those addressed in Section

121(d)(4) of the Superfund Amendments

and Reauthorization Act of 1986

(SARA). SARA recognizes that cleanup

of contamination could sometimes

cause environmental harm

disproportionate to the effects it would

alleviate. For example, if fragile

ecosystems would be impaired by any

reasonable restoration process (or by

carrying a restoration process to extreme

lengths to remove small amounts of

residual contamination), then it might

be prudent not to completely restore

groundwater quality. Such a situation

might occur, for example, if the quantity

of water that would be lost during

remediation is a significant fraction of

that available in an aquifer that

recharges very slowly. Decisions

regarding tradeoffs of environmental

damage can only be based on

characteristics peculiar to the specific

location of the site. We do not yet know

whether such situations exist in the

UMTRCA program, but EPA believes

that use of supplemental standards

should be possible in such situations,

after thorough investigation and

consideration of all reasonable

restoration alternatives.
2862 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

Based on currently available

information, we are not aware that at

least substantial restoration of

groundwater quality is technically

impracticable from an engineering

perspective at any of the designated

sites. However, our information is

incomplete. For example, there may not

be enough water available in a very

small aquifer to carry out remediation

and retain the groundwater resource, or,

in other cases, some contaminants may

not be removable without destroying the

aquifer. EPA believes that DOE should

not be required to institute active

measures that would completely restore

groundwater at these sites if such

restoration is technically impracticable

from an engineering perspective, and if,

at a minimum, protection of human

health and the environment is assured.

Consistent with the provisions of SARA

for remediation of waste sites generally,

the standards therefore permit

supplemental standards in such

situations at levels achievable by sitespecific alternate remedial actions. A

finding of technical impracticability

from an engineering perspective

requires careful and extensive

documentation, including an analysis of

the degree to which remediation is

practicable. It should be noted that the

phrase ‘‘technically impracticable from

an engineering perspective’’ means that

the remedial action cannot reasonably

be put into practice; it does not mean a

conclusion derived from the balancing

of costs and benefits. In addition to

documentation of technical matters

related to cleanup technology, DOE

should also include a detailed

assessment of such site-specific matters

as transmissivity of the geologic

formation, aquifer recharge and storage,

contaminant properties (e.g.,

withdrawal and treatability potential),

and the extent of contamination.

Finally, for aquifers where

compliance with the groundwater

standards can be projected to occur

naturally within a period of less than

100 years, and where the groundwater is

not now used for a public water system

and is not now projected to be so used

within this period, this rule permits

extension of the remedial period to that

time, provided institutional control and

an adequate verification plan which

assures satisfaction of beneficial uses is

established and maintained throughout

this extended remedial period.

Active restoration should be carefully

considered when evaluating the use of

such passive restoration. The provision

to permit reliance on natural restoration

is based on the judgment that sole

reliance on active cleanup may not

always be warranted under these

standards promulgated pursuant to

UMTRCA. This may be the case for

situations where active cleansing to

completely achieve the standards is

impracticable, environmentally

damaging, or excessively costly, if

groundwater can reach the levels

required by the standards through

natural flushing within an acceptable

period of time. This mechanism may be

considered where groundwater

concentration limits can be met through

partial (or complete) reliance on natural

processes and no use of the water as a

source for a public water system exists

or is projected. Any institutional control

that may be required to effectively

protect public health and the

environment and assure that beneficial

uses that the water could have satisfied

are provided for in the interim must be

verified for effectiveness and modified

as necessary. Alternate standards are not

required where final cleanup is to be

accomplished through natural flushing,

since those established under

§ 192.02(c)(3) must be met at the end of

the remedial period.

The regulations establish a time limit

on such extension of the remedial

period to limit reliance on extended use

of institutional controls to manage

public access to contaminated

groundwater. Following the precedent

established by our rule for high-level

radioactive wastes (40 CFR 191.14(a)),

use of institutional controls is permitted

for this purpose only when they will be

needed for periods of less than 100

years.

The effectiveness of institutional

controls must be verified and

maintained over the entire period of

time that they are in use. Examples of

acceptable measures include use

restrictions enforceable by the

administrative or judicial branches of

government entities, and measures with

a high degree of permanence, such as

Federal or State ownership of the land

containing the contaminated water. In

some instances, a combination of

institutional controls may be needed to

provide adequate protection, such as

providing an alternate source of water

for drinking or other beneficial uses and

restricting inappropriate use of

contaminated groundwater. However,

institutional control provisions are not

intended to require DOE to provide

water for uses that the groundwater

would not have been available or

suitable for in the absence of

contamination from residual radioactive

materials. Institutional controls that are

not adequate by themselves include

such measures as health advisories,

signs, posts, admonitions, or any other

measure that requires the voluntary

cooperation of private parties. However,

such measures may be used to

complement other enforceable

institutional controls.

Restoration of groundwater may be

carried out by removal, wherein the

contaminated water is removed from the

aquifer, treated, and either disposed of,

used, or re-injected into the aquifer, and

in situ, through the addition of chemical

or biological agents to fix, reduce, or

eliminate the contamination in place.

Appropriate restoration will depend on

characteristics of specific sites and may

involve use of a combination of

methods. Water can be removed from an

aquifer by pumping it out through wells

or by collecting the water from intercept

trenches. Slurry walls can sometimes be

put in place to contain contamination

and prevent further migration of

contaminants, so that the volume of

contaminated water that must be treated

is reduced. The background information

document contains a more extensive

discussion of candidate restoration

methods.

Previously EPA reviewed preliminary

information for all 24 sites and detailed

information for 14 to make a

preliminary assessment of the extent of

the potential applicability of

supplemental standards and the use of

passive remediation. Approximately

two-thirds of the sites appear to be

located over potable (or otherwise

useful) groundwater and the balance

over limited use groundwaters. DOE,

based on more recent information, feels

that up to ten sites are candidates for

supplemental standards, and that the

rate at which natural flushing is

occurring at up to eight of the sites

permits consideration of passive

remediation under institutional control

as the sole remedial method. Some sites

exhibit conditions that could be

amenable to a combination of strategies.

Further, EPA is not able to predict the

applicability of provisions regarding

technical impracticability or excess

environmental harm, since this requires

detailed analysis of specific sites, but

anticipates that wide application is

unlikely. It is emphasized that the above

assessment is not based on final results

for the vast majority of these sites, and

is, therefore, subject to change.

RCRA regulations, for hazardous

waste disposal units regulated by EPA,

provide that acceptable concentrations

of constituents in groundwater

(including ACLs) are determined by the

Regional Administrator (or an

authorized State). EPA’s regulations

under Title II of UMTRCA provide that

the NRC, which regulates active sites,

replace the EPA Regional Administrator

for the above functions when any
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2863

1Protecting the Nation’s Groundwater: EPA’s

Strategy for the 1990s, The Final Report of the EPA

Groundwater Task Force, U.S. Environmental

Protection Agency, Washington, (Report 21Z–1020),

July 1991.

contamination permitted by an ACL will

remain on the licensed site or within

500 meters of the disposal area,

whichever is closer. Because Section

108(a) of UMTRCA requires the

Commission’s concurrence with DOE’s

selection and performance of remedial

actions to conform to EPA’s standards,

this rule makes the same provision for

administration by the NRC of those

functions for Title I as it did in the case

of the Title II standards, and also

provides for NRC concurrence on

supplemental standards.

V. Implementation

UMTRCA requires the Secretary of

Energy to select and perform the

remedial actions needed to implement

these standards, with the full

participation of any State that shares the

cost. The NRC must concur with these

actions and, when appropriate, the

Secretary of Energy must also consult

with affected Indian tribes and the

Secretary of the Interior.

The cost of remedial actions is being

borne by the Federal Government and

the States as prescribed by UMTRCA.

The clean-up of groundwater is a largescale undertaking for which there is

relatively little long-term experience.

Groundwater conditions at the inactive

processing sites vary greatly, and, as

noted above, engineering experience

with some of the required remedial

actions is limited. Although preliminary

engineering assessments have been

performed, specific engineering

requirements and detailed costs to meet

the groundwater standards at each site

have yet to be determined. We believe

that costs averaging about 10–15 million

(1993) dollars for each of the

approximately fourteen tailings sites at

which remedial action may be required

are most likely.

The benefits from the cleanup of this

groundwater are difficult to quantify. In

some instances, groundwater that is

contaminated by tailings is now in use

and will be restored. Future uses that

will be preserved by cleanup are

difficult to project. In the areas where

the tailings were processed,

groundwater is an important resource

due to the arid condition of the land.

However, much of the contamination at

these sites occurs in shallow alluvial

aquifers. At some of these sites such

aquifers have limited use because of

their generally poor quality and the

availability of better quality water from

deeper aquifers.

Implementation of the disposal

standard for protection of groundwater

will require a judgment that the method

chosen provides a reasonable

expectation that the provisions of the

standard will be met, to the extent

reasonably achievable, for up to 1000

years and, in any case, for at least 200

years. This judgment will necessarily be

based on site-specific analyses of the

properties of the sites, candidate

disposal systems, and the potential

effects of natural processes over time.

Therefore, the measures required to

satisfy the standard will vary from site

to site. Actual site data, computational

models, and expert judgment will be the

major tools in deciding that a proposed

disposal system will satisfy the

standard.

The purpose of the groundwater

cleanup standard is to provide the

maximum reasonable protection of

public health and the environment.

Costs incurred by remedial actions

should be directed toward this purpose.

We intend the standards to be

implemented using verification

procedures whose cost and technical

requirements are reasonable. Procedures

that provide a reasonable assurance of

compliance with the standards will be

adequate. Measurements to assess

existing contamination and to determine

compliance with the cleanup standards

should be performed with 1 reasonable

survey and sampling procedures

designed to minimize the cost of

verification.

The explanations regarding

implementation of these regulations in

§§ 192.20(a)(2) and (3) have been

revised to remove those provisions that

the Court remanded and to reflect these

new requirements.

These standards are not expected to

affect the disposal work DOE has

already performed on tailings. On the

basis of consultations with DOE and

NRC, we expect, in general, that a pile

designed to comply with the disposal

standards proposed on September 24,

1987, will also comply with these

disposal standards for the control of

groundwater contamination. DOE will

have to determine, with the concurrence

of the NRC, what additional work may

be needed to comply with the

groundwater cleanup requirements.

However, any such cleanup work

should not adversely affect the control

systems for tailings piles that have

already been or are currently being

installed.

However, at three sites (Canonsburg,

PA; Shiprock, NM; and Salt Lake City,

UT) the disposal design was based on

standards remanded in part on

September 3, 1985. We have considered

these sites separately, based on

information supplied by DOE, and

reached the tentative conclusion that

modification of the existing disposal

cells is not warranted at any of them.

Final determinations will be made by

DOE, with the concurrence of NRC.

The disposal site at Canonsburg, PA,

is located above the banks of Chartiers

Creek. Contamination that might seep

from the encapsulated tailings will

reach the surface within the site

boundary, and is then diluted by water

in the creek to insignificant levels.

Under these circumstances, this site

qualifies for an ACL under

§ 192.02(c)(3)(ii), and modification of

the existing disposal cell is not

warranted.

The site at Shiprock, NM, which is

located above the floodplain of the San

Juan River, is over an aquifer that may

not be useful as a source of water for

drinking or other beneficial purpose

because of its quality, areal extent, and

yield. Most of the groundwater in this

aquifer appears to have originated from

seepage of tailings liquor from mill

impoundments and not to be

contributing to contamination of any

currently or potentially useful aquifer.

Additionally, the quality of this water

may be degraded by uncontrolled

disposal of municipal refuse north and

south of the site. DOE is currently in the

process of completing its

characterization of this groundwater,

and may or may not recommend use of

a supplemental standard under

§ 192.21(g). In any case, however, it

appears unlikely that modification of

the existing disposal cell will be

necessary.

The site containing the tailings from

the Salt Lake City mill is located at

Clive, Utah, over groundwater that

contains dissolved solids in excess of

10,000 mg/l and is not contributing to

contamination of any currently or

potentially useful aquifer. Under these

circumstances, this site also qualifies for

a supplemental standard under

§ 192.21(g), and modification of the

existing disposal cell is not warranted.

VI. Relationship to Other Policy and

Requirements

In July 1991 EPA completed

development of a strategy to guide

future EPA and State activities in

groundwater protection and cleanup. A

key element of this strategy is a

statement of ‘EPA Groundwater

Protection Principles’ 1 that has as its

overall goals the prevention of adverse

effects on human health and the

environment and protection of the

environmental integrity of the nation’s

groundwater resources. To achieve these
2864 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

goals, EPA developed principles

regarding prevention; remediation; and

Federal, State, and local responsibilities.

These principles are set forth and their

implementation by this rule

summarized below.

(1) With respect to prevention:

groundwater should be protected to ensure

that the nation’s currently used and

reasonably expected drinking water supplies,

both public and private, do not present

adverse health risks and are preserved for

present and future generations. Groundwater

should also be protected to ensure that

groundwater that is closely hydrologically

connected to surface waters does not

interfere with the attainment of surface water

quality standards, which is necessary to

protect the integrity of associated ecosystems.

Groundwater protection can be achieved

through a variety of means including:

pollution prevention programs; source

controls; siting controls; the designation of

wellhead protection areas and future public

water supply areas; and the protection of

aquifer recharge areas. Efforts to protect

groundwater must also consider the use,

value, and vulnerability of the resource, as

well as social and economic values.

This rule for uranium mill tailings

protects groundwater by requiring that

disposal piles be designed to avoid any

new contamination of groundwater that

would threaten human health or the

environment in the future. Water is

scarce in the Western States where these

disposal sites occur. Currently almost

half of the water consumed in Arizona

and New Mexico and 20 to 30 percent

of the water consumed in Utah,

Colorado, Idaho, and Texas is

groundwater. The population in the

Mountain States is expected to increase

more than that of any other region

between now and the year 2010. In

particular, the population in Colorado,

New Mexico, Arizona, and Utah is

expected to increase dramatically. Thus,

in order to ensure that all currently used

and reasonably expected drinking water

supplies near these sites, both public

and private, are adequately protected for

use by present and future generations,

these rules apply drinking water

standards to all potable groundwater.

The rule also requires that

hydrologically-connected aquifers and

surface waters, including designated

wellhead protection areas and future

public water supply areas, be identified

and protected, and that other beneficial

uses of groundwater besides drinking be

identified and protected, including the

integrity of associated ecosystems. In

this regard we note that DOE has not

identified any critical aquatic habitats

that have been or could be adversely

affected by contamination from these

sites.

(2) With respect to remediation:

groundwater remediation activities must be

prioritized to limit the risk of adverse effects

to human health risks first and then to restore

currently used and reasonably expected

sources of drinking water and groundwater

closely hydrologically connected to surface

waters, whenever such restorations are

practicable and attainable.

Pursuant to our responsibilities under

Section 102(b) of UMTRCA, EPA

advised DOE in 1979 concerning the

criteria which should govern the order

in which these sites should be cleaned

up. Those criteria specified, in essence,

that sites capable of affecting the health

of human populations the most should

be remediated first. As a result DOE has

divided the 24 sites into three levels of

priority, based on the populations

affected. In order to facilitate

implementation of these principles, we

have, in this rule, provided DOE with

flexibility to prioritize their cleanup

activities so as to first minimize human

exposure, then restore reasonably

expected drinking water sources, and

finally to clean up groundwater only

when restoration is practicable and

attainable. This has been done by

relaxing the requirements for cleanup of

water:

(a) If it is not a current or potential

source of drinking water (i.e., it meets

the definition of limited use),

(b) Where natural processes will

achieve the standards and there is no

current or planned use,

(c) Where adverse environmental

impact will occur, and (d) where

cleanup is technologically

impracticable.

(3) With respect to Federal, State, and local

responsibilities: the primary responsibility

for coordinating and implementing

groundwater protection programs has always

been and should continue to be vested with

the States. An effective groundwater

protection program should link Federal,

State, and local activities into a coherent and

coordinated plan of action. EPA should

continue to improve coordination of

groundwater protection efforts within the

Agency and with other Federal agencies with

groundwater responsibilities.

In the case of the sites covered by

these regulations, UMTRCA specifies a

primary role for Federal rather than

State agencies. However, since these

regulations are modeled after existing

RCRA regulations, this will serve to

insure coherence and coordination with

similar prevention and remediation

actions by EPA, the States, and other

Federal agencies. For example, the

concentration limits in groundwater for

listed constituents at the sites covered

by this rule are the same as those

specified for cleanup and disposal at

RCRA sites by EPA and the States and

at uranium mill sites licensed by NRC.

Executive Order 12866

Under Executive Order 12866 (58 FR

51735; October 4, 1993), EPA must

determine whether a rule is

‘‘significant’’ and therefore subject to

review by the Office of Management and

Budget (OMB) and the requirements of

the Executive Order. The Order defines

‘‘significant regulatory action’’ as one

that is likely to result in a rule that may:

(1) Have an annual effect on the

economy of $100 million or more or

adversely effect in a material way the

economy, a sector of the economy,

productivity, competition, jobs, the

environment, public health or safety, or

State, local or tribal governments or

communities;

(2) Create a serious inconsistency or

otherwise interfere with an action taken

or planned by another agency;

(3) Materially alter the budgetary

impact of entitlements, grants, user fees,

or loan programs or the rights and

obligations of the recipients thereof; or

(4) Raise novel legal or policy issues

arising out of legal mandates, the

President’s priorities, or the principles

set forth in the Executive Order.

Pursuant to the terms of Executive

Order 12866, it has been determined

that this rule is may be a ‘‘significant

regulatory action,’’ because it may

qualify under criterion #4 above on the

basis of comments submitted to EPA by

letter on January 15, 1993, as a result of

OMB review under the previous

Executive Order 12291. This action was

therefore resubmitted to OMB for

review. Comments from OMB to EPA for

their review under the previous

Executive Order and EPA’s response to

those comments are included in the

docket. Any changes made in response

to OMB suggestions or

recommendations as a result of the

current review will be documented in

the public record.

Paperwork Reduction Act

Under the Paperwork Reduction Act

of 1986, the Agency is required to state

the information collection requirements

of any standard published on or after

July 1, 1988. In response to this

requirement, this standard contains no

information collection requirements and

imposes no reporting burden on the

public.

List of Subjects in 40 CFR Part 192

Environmental protection,

Groundwater, Radiation protection,

Uranium.
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2865

1Because the standard applies to design,

monitoring after disposal is not required to

demonstrate compliance with respect to § 192.02(a)

and (b).

2This average shall apply over the entire surface

of the disposal site and over at least a one-year

period. Radon will come from both residual

radioactive materials and from materials covering

them. Radon emissions from the covering materials

should be estimated as part of developing a

remedial action plan for each site. The standard,

however, applies only to emissions from residual

radioactive materials to the atmosphere.

Dated: December 14, 1994.

Carol M. Browner,

Administrator, Environmental Protection

Agency.

For the reasons set forth in the

preamble, 40 CFR part 192 is amended

as follows:

PART 192—HEALTH AND

ENVIRONMENTAL PROTECTION

STANDARDS FOR URANIUM AND

THORIUM MILL TAILINGS

1. The authority citation for part 192

continues to read as follows:

Authority: Section 275 of the Atomic

Energy Act of 1954, 42 U.S.C. 2022, as added

by the Uranium Mill Tailings Radiation

Control Act of 1978, Pub. L. 95–604, as

amended.

Subpart A—Standards for the Control

of Residual Radioactive Materials From

Inactive Uranium Processing Sites

2. Section 192.01 is amended by

revising paragraphs (a) and (e) and

adding paragraphs (g) through (r) to read

as follows:

§ 192.01 Definitions.

(a) Residual radioactive material

means:

(1) Waste (which the Secretary

determines to be radioactive) in the

form of tailings resulting from the

processing of ores for the extraction of

uranium and other valuable constituents

of the ores; and

(2) Other wastes (which the Secretary

determines to be radioactive) at a

processing site which relate to such

processing, including any residual stock

of unprocessed ores or low-grade

materials.

* * * * *

(e) Depository site means a site (other

than a processing site) selected under

Section 104(b) or 105(b) of the Act.

* * * * *

(g) Act means the Uranium Mill

Tailings Radiation Control Act of 1978,

as amended.

(h) Administrator means the

Administrator of the Environmental

Protection Agency.

(i) Secretary means the Secretary of

Energy.

(j) Commission means the Nuclear

Regulatory Commission.

(k) Indian tribe means any tribe, band,

clan, group, pueblo, or community of

Indians recognized as eligible for

services provided by the Secretary of the

Interior to Indians.

(l) Processing site means:

(1) Any site, including the mill,

designated by the Secretary under

Section 102(a)(1) of the Act; and

(2) Any other real property or

improvement thereon which is in the

vicinity of such site, and is determined

by the Secretary, in consultation with

the Commission, to be contaminated

with residual radioactive materials

derived from such site.

(m) Tailings means the remaining

portion of a metal-bearing ore after some

or all of such metal, such as uranium,

has been extracted.

(n) Disposal period means the period

of time beginning March 7, 1983 and

ending with the completion of all

subpart A requirements specified under

a plan for remedial action except those

specified in § 192.03 and § 192.04.

(o) Plan for remedial action means a

written plan (or plans) for disposal and

cleanup of residual radioactive

materials associated with a processing

site that incorporates the results of site

characterization studies, environmental

assessments or impact statements, and

engineering assessments so as to satisfy

the requirements of subparts A and B of

this part. The plan(s) shall be developed

in accordance with the provisions of

Section 108(a) of the Act with the

concurrence of the Commission and in

consultation, as appropriate, with the

Indian Tribe and the Secretary of

Interior.

(p) Post-disposal period means the

period of time beginning immediately

after the disposal period and ending at

termination of the monitoring period

established under § 192.03.

(q) Groundwater means water below

the ground surface in a zone of

saturation.

(r) Underground source of drinking

water means an aquifer or its portion:

(1)(i) Which supplies any public

water system as defined in § 141.2 of

this chapter; or

(ii) Which contains a sufficient

quantity of groundwater to supply a

public water system; and

(A) Currently supplies drinking water

for human consumption; or

(B) Contains fewer than 10,000 mg/l

total dissolved solids; and

(2) Which is not an exempted aquifer

as defined in § 144.7 of this chapter.

3. Section 192.02 is revised to read as

follows:

§ 192.02 Standards.

Control of residual radioactive

materials and their listed constituents

shall be designed 1 to:

(a) Be effective for up to one thousand

years, to the extent reasonably

achievable, and, in any case, for at least

200 years, and,

(b) Provide reasonable assurance that

releases of radon-222 from residual

radioactive material to the atmosphere

will not:

(1) Exceed an average 2 release rate of

20 picocuries per square meter per

second, or

(2) Increase the annual average

concentration of radon-222 in air at or

above any location outside the disposal

site by more than one-half picocurie per

liter.

(c) Provide reasonable assurance of

conformance with the following

groundwater protection provisions:

(1) The Secretary shall, on a sitespecific basis, determine which of the

constituents listed in Appendix I to Part

192 are present in or reasonably derived

from residual radioactive materials and

shall establish a monitoring program

adequate to determine background

levels of each such constituent in

groundwater at each disposal site.

(2) The Secretary shall comply with

conditions specified in a plan for

remedial action which includes

engineering specifications for a system

of disposal designed to ensure that

constituents identified under paragraph

(c)(1) of this section entering the

groundwater from a depository site (or

a processing site, if residual radioactive

materials are retained on the site) will

not exceed the concentration limits

established under paragraph (c)(3) of

this section (or the supplemental

standards established under § 192.22) in

the uppermost aquifer underlying the

site beyond the point of compliance

established under paragraph (c)(4) of

this section.

(3) Concentration limits:

(i) Concentration limits shall be

determined in the groundwater for

listed constituents identified under

paragraph (c)(1) of this section. The

concentration of a listed constituent in

groundwater must not exceed:

(A) The background level of that

constituent in the groundwater; or

(B) For any of the constituents listed

in Table 1 to subpart A, the respective

value given in that Table if the

background level of the constituent is

below the value given in the Table; or

(C) An alternate concentration limit

established pursuant to paragraph

(c)(3)(ii) of this section.

(ii)(A) The Secretary may apply an

alternate concentration limit if, after
2866 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

considering remedial or corrective

actions to achieve the levels specified in

paragraphs (c)(3)(i)(A) and (B) of this

section, he has determined that the

constituent will not pose a substantial

present or potential hazard to human

health and the environment as long as

the alternate concentration limit is not

exceeded, and the Commission has

concurred.

(B) In considering the present or

potential hazard to human health and

the environment of alternate

concentration limits, the following

factors shall be considered:

(1) Potential adverse effects on

groundwater quality, considering:

(i) The physical and chemical

characteristics of constituents in the

residual radioactive material at the site,

including their potential for migration;

(ii) The hydrogeological

characteristics of the site and

surrounding land;

(iii) The quantity of groundwater and

the direction of groundwater flow;

(iv) The proximity and withdrawal

rates of groundwater users;

(v) The current and future uses of

groundwater in the region surrounding

the site;

(vi) The existing quality of

groundwater, including other sources of

contamination and their cumulative

impact on the groundwater quality;

(vii) The potential for health risks

caused by human exposure to

constituents;

(viii) The potential damage to wildlife,

crops, vegetation, and physical

structures caused by exposure to

constituents;

(ix) The persistence and permanence

of the potential adverse effects;

(x) The presence of underground

sources of drinking water and exempted

aquifers identified under § 144.7 of this

chapter; and

(2) Potential adverse effects on

hydraulically-connected surface-water

quality, considering:

(i) The volume and physical and

chemical characteristics of the residual

radioactive material at the site;

(ii) The hydrogeological

characteristics of the site and

surrounding land;

(iii) The quantity and quality of

groundwater, and the direction of

groundwater flow;

(iv) The patterns of rainfall in the

region;

(v) The proximity of the site to surface

waters;

(vi) The current and future uses of

surface waters in the region surrounding

the site and any water quality standards

established for those surface waters;

(vii) The existing quality of surface

water, including other sources of

contamination and their cumulative

impact on surface water quality;

(viii) The potential for health risks

caused by human exposure to

constituents;

(ix) The potential damage to wildlife,

crops, vegetation, and physical

structures caused by exposure to

constituents; and

(x) The persistence and permanence

of the potential adverse effects.

(4) Point of compliance: The point of

compliance is the location at which the

groundwater concentration limits of

paragraph (c)(3) of this section apply.

The point of compliance is the

intersection of a vertical plane with the

uppermost aquifer underlying the site,

located at the hydraulically

downgradient limit of the disposal area

plus the area taken up by any liner,

dike, or other barrier designed to

contain the residual radioactive

material.

(d) Each site on which disposal occurs

shall be designed and stabilized in a

manner that minimizes the need for

future maintenance.

4. Section 192.03 is added to read as

follows:

§ 192.03 Monitoring.

A groundwater monitoring plan shall

be implemented, to be carried out over

a period of time commencing upon

completion of remedial actions taken to

comply with the standards in § 192.02,

and of a duration which is adequate to

demonstrate that future performance of

the system of disposal can reasonably be

expected to be in accordance with the

design requirements of § 192.02(c). This

plan and the length of the monitoring

period shall be modified to incorporate

any corrective actions required under

§ 192.04 or § 192.12(c).

5. Section 192.04 is added to read as

follows:

§ 192.04 Corrective Action.

If the groundwater concentration

limits established for disposal sites

under provisions of § 192.02(c) are

found or projected to be exceeded, a

corrective action program shall be

placed into operation as soon as is

practicable, and in no event later than

eighteen (18) months after a finding of

exceedance. This corrective action

program will restore the performance of

the system of disposal to the original

concentration limits established under

§ 192.02(c)(3), to the extent reasonably

achievable, and, in any case, as a

minimum shall:

(a) Conform with the groundwater

provisions of § 192.02(c)(3), and

(b) Clean up groundwater in

conformance with subpart B, modified

as appropriate to apply to the disposal

site.

6. Table 1 is added to subpart A to

read as follows:

TABLE 1 TO SUBPART A.—MAXIMUM

CONCENTRATION OF CONSTITUENTS

FOR GROUNDWATER PROTECTION

Constituent concentration 1 Maximum

Arsenic ................................ 0.05

Barium ................................. 1.0

Cadmium ............................. 0.01

Chromium ............................ 0.05

Lead .................................... 0.05

Mercury ............................... 0.002

Selenium ............................. 0.01

Silver ................................... 0.05

Nitrate (as N) ...................... 10.

Molybdenum ........................ 0.1

Combined radium-226 and

radium-228.

5 pCi/liter

Combined uranium-234 and

uranium-238 2.

30 pCi/liter

Gross alpha-particle activity

(excluding radon and uranium).

15 pCi/liter

Endrin (1,2,3,4,10,10-

hexachloro-6,7-exposy1,4,4a,5,6,7,8,8aoctahydro-1,4-endo,endo5,8-

dimethanonaphthalene).

0.0002

Lindane (1,2,3,4,5,6-

hexachlorocyclohexane,

gamma insomer).

0.004

Methoxychlor (1,1,1-

trichloro-2,2’-bis(pmethoxyphenylethane)).

0.1

Toxaphene (C10H10Cl6,

technical chlorinated

camphene, 67–69 percent

chlorine).

0.005

2,4-D (2,4-

dichlorophenoxyacetic

acid).

0.1

2,4,5-TP Silvex (2,4,5-

trichlorophenoxypropionic

acid).

0.01

1 Milligrams per liter, unless stated otherwise. 2Where secular equilibrium obtains, this criterion will be satisfied by a concentration of

0.044 milligrams per liter (0.044 mg/l). For

conditions of other than secular equilibrium, a

corresponding value may be derived and applied, based on the measured site-specific

ratio of the two isotopes of uranium.

Subpart B—Standards for Cleanup of

Land and Buildings Contaminated with

Residual Radioactive Materials from

Inactive Uranium Processing Sites

7. Section 192.11 is amended by

revising paragraph (a) and adding

paragraph (e) to read as follows:

192.11 Definitions.

(a) Unless otherwise indicated in this

subpart, all terms shall have the same

meaning as defined in subpart A.

* * * * *
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2867

(e) Limited use groundwater means

groundwater that is not a current or

potential source of drinking water

because (1) the concentration of total

dissolved solids is in excess of 10,000

mg/l, or (2) widespread, ambient

contamination not due to activities

involving residual radioactive materials

from a designated processing site exists

that cannot be cleaned up using

treatment methods reasonably employed

in public water systems, or (3) the

quantity of water reasonably available

for sustained continuous use is less than

150 gallons per day. The parameters for

determining the quantity of water

reasonably available shall be

determined by the Secretary with the

concurrence of the Commission.

8. In § 192.12, the introductory text is

republished without change and

paragraph (c) is added to read as

follows:

192.12 Standards.

Remedial actions shall be conducted

so as to provide reasonable assurance

that, as a result of residual radioactive

materials from any designated

processing site:

* * * * *

(c) The Secretary shall comply with

conditions specified in a plan for

remedial action which provides that

contamination of groundwater by listed

constituents from residual radioactive

material at any designated processing

site (§ 192.01(1)) shall be brought into

compliance as promptly as is reasonably

achievable with the provisions of

§ 192.02(c)(3) or any supplemental

standards established under § 192.22.

For the purposes of this subpart:

(1) A monitoring program shall be

carried out that is adequate to define

backgroundwater quality and the areal

extent and magnitude of groundwater

contamination by listed constituents

from residual radioactive materials

(§ 192.02(c)(1)) and to monitor

compliance with this subpart. The

Secretary shall determine which of the

constituents listed in Appendix I to part

192 are present in or could reasonably

be derived from residual radioactive

material at the site, and concentration

limits shall be established in accordance

with § 192.02(c)(3).

(2) (i) If the Secretary determines that

sole reliance on active remedial

procedures is not appropriate and that

cleanup of the groundwater can be more

reasonably accomplished in full or in

part through natural flushing, then the

period for remedial procedures may be

extended. Such an extended period may

extend to a term not to exceed 100 years

if:

(A) The concentration limits

established under this subpart are

projected to be satisfied at the end of

this extended period,

(B) Institutional control, having a high

degree of permanence and which will

effectively protect public health and the

environment and satisfy beneficial uses

of groundwater during the extended

period and which is enforceable by the

administrative or judicial branches of

government entities, is instituted and

maintained, as part of the remedial

action, at the processing site and

wherever contamination by listed

constituents from residual radioactive

materials is found in groundwater, or is

projected to be found, and

(C) The groundwater is not currently

and is not now projected to become a

source for a public water system subject

to provisions of the Safe Drinking Water

Act during the extended period.

(ii) Remedial actions on groundwater

conducted under this subpart may occur

before or after actions under Section

104(f)(2) of the Act are initiated.

(3) Compliance with this subpart shall

be demonstrated through the monitoring

program established under paragraph

(c)(1) of this section at those locations

not beneath a disposal site and its cover

where groundwater contains listed

constituents from residual radioactive

material.

Subpart C—Implementation

9. In § 192.20, paragraphs (a)(2) and

(a)(3) and the first sentence of paragraph

(b)(l) are revised and paragraphs (a)(4)

and (b)(4) are added to read as follows:

192.20 Guidance for implementation.

* * * * *

(a)(1) * * *

(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 § 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 § 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

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 § 192.03

should be designed to include

verification of site-specific assumptions

used to project the performance of the

disposal system. Prevention of
2868 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

1The abbreviation N.O.S. (not otherwise

specified) signifies those members of the general

class not specifically listed by name in this

appendix.

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

(§ 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

§ 192.04 during the disposal period,

unless the disposal operation is

suspended prior to completion for other

than seasonal reasons.

(b)(l) Compliance with § 192.12(a) and

(b) of subpart B, to the extent practical,

should be demonstrated through

radiation surveys. * * *

* * * * *

(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

§ 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 (§ 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 § 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.

10. In § 192.21, the introductory text

and paragraph (b) are revised, paragraph

(f) is redesignated as paragraph (h), and

new paragraphs (f) and (g) are added to

read as follows:

§ 192.21 Criteria for applying supplemental

standards

Unless otherwise indicated in this

subpart, all terms shall have the same

meaning as defined in Title I of the Act

or in subparts A and B. The

implementing agencies may (and in the

case of paragraph (h) of this section

shall) apply standards under § 192.22 in

lieu of the standards of subparts A or B

if they determine that any of the

following circumstances exists:

* * * * *

(b) Remedial actions to satisfy the

cleanup standards for land, § 192.12(a),

and groundwater, § 192.12(c), or the

acquisition of minimum materials

required for control to satisfy

§§ 192.02(b) and (c), would,

notwithstanding reasonable measures to

limit damage, directly produce health

and environmental harm that is clearly

excessive compared to the health and

environmental benefits, now or in the

future. A clear excess of health and

environmental harm is harm that is

long-term, manifest, and grossly

disproportionate to health and

environmental benefits that may

reasonably be anticipated.

* * * * *

(f) The restoration of groundwater

quality at any designated processing site

under § 192.12(c) is technically

impracticable from an engineering

perspective.

(g) The groundwater meets the criteria

of § 192.11(e).

* * * * *

11. In § 192.22, paragraphs (a) and (b)

are revised and paragraph (d) is added

to read as follows:

192.22 Supplemental standards.

* * * * *

(a) When one or more of the criteria

of § 192.21(a) through (g) applies, the

Secretary shall select and perform that

alternative remedial action that comes

as close to meeting the otherwise

applicable standard under § 192.02(c)(3)

as is reasonably achievable.

(b) When § 192.21(h) applies,

remedial actions shall reduce other

residual radioactivity to levels that are

as low as is reasonably achievable and

conform to the standards of subparts A

and B to the maximum extent

practicable.

* * * * *

(d) When § 192.21(b), (f), or (g) apply,

implementing agencies shall apply any

remedial actions for the restoration of

contamination of groundwater by

residual radioactive materials that is

required to assure, at a minimum,

protection of human health and the

environment. In addition, when

§ 192.21(g) applies, supplemental

standards shall ensure that current and

reasonably projected uses of the affected

groundwater are preserved.

12. Appendix I is added to part 192

to read as follows:

Appendix I to Part 192—Listed Constituents

Acetonitrile

Acetophenone (Ethanone, 1-phenyl)

2-Acetylaminofluorene (Acetamide, N-9Hfluoren-2-yl-)

Acetyl chloride

1-Acetyl-2-thiourea (Acetamide, N-

(aminothioxymethyl)-)

Acrolein (2-Propenal)

Acrylamide (2-Propenamide)

Acrylonitrile (2-Propenenitrile)

Aflatoxins

Aldicarb (Propenal, 2-methyl-2-(methylthio)-

,O-[(methylamino)carbonyl]oxime

Aldrin (1,4:5,8-Dimethanonaphthalene,

1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8ahexahydro(1α,4α,4aβ,5α,8α,8αβ)-)

Allyl alcohol (2-Propen-1-ol)

Allyl chloride (1-Propane,3-chloro)

Aluminum phosphide

4-Aminobiphenyl ([1,1’-Biphenyl]-4-amine)

5-(Aminomethyl)-3-isoxazolol (3(2H)-

Isoxazolone,5-(aminomethyl)-)

4-Aminopyridine (4-Pyridineamine)

Amitrole (lH-1,2,4-Triazol-3-amine)

Ammonium vanadate (Vanadic acid,

ammonium salt)

Aniline (Benzenamine)

Antimony and compounds, N.O.S.1
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2869

Aramite (Sulfurous acid, 2-chloroethyl 2-[4-

(1,1-dimethylethyl)phenoxy]-1-methylethyl

ester)

Arsenic and compounds, N.O.S.

Arsenic acid (Arsenic acid H3AsO4)

Arsenic pentoxide (Arsenic oxide As2O5)

Auramine (Benzamine, 4,4’-

carbonimidoylbis[N,N-dimethyl-])

Azaserine (L-Serine, diazoacetate (ester))

Barium and compounds, N.O.S.

Barium cyanide

Benz[c]acridine (3,4-Benzacridine)

Benz[a]anthracene (1,2-Benzanthracene)

Benzal chloride (Benzene, dichloromethyl-)

Benzene (Cyclohexatriene)

Benzenearsonic acid (Arsenic acid, phenyl-)

Benzidine ([1,1’-Biphenyl]-4,4’-diamine)

Benzo[b]fluoranthene

(Benz[e]acephananthrylene)

Benzo[j]fluoranthene

Benzo[k]fluoranthene

Benzo[a]pyrene

p-Benzoquinone (2,5-Cyclohexadiene-1,4-

dione)

Benzotrichloride (Benzene, (trichloromethyl)-)

Benzyl chloride (Benzene, (chloromethyl)-)

Beryllium and compounds, N.O.S.

Bromoacetone (2-Propanone, 1-bromo-)

Bromoform (Methane, tribromo-)

4-Bromophenyl phenyl ether (Benzene, lbromo-4-phenoxy-)

Brucine (Strychnidin-10-one, 2,3-dimethoxy-)

Butyl benzyl phthalate (1,2-

Benzenedicarbozylic acid, butyl

phenylmethyl ester)

Cacodylic acid (Arsinic acid, dimethyl)

Cadmium and compounds, N.O.S.

Calcium chromate (Chromic acid H2CrO4,

calcium salt)

Calcium cyanide (Ca(CN)2)

Carbon disulfide

Carbon oxyfluoride (Carbonic difluoride)

Carbon tetrachloride (Methane, tetrachloro-)

Chloral (Acetaldehyde, trichloro-)

Chlorambucil (Benzenebutanoic acid, 4-

[bis(2-chloroethyl)amino]-)

Chlordane (4,7-Methano-1Hindene,1,2,4,5,6,7,8,8-octachloro2,3,3a,4,7,7a-hexahydro-)

Chlorinated benzenes, N.O.S.

Chlorinated ethane, N.O.S.

Chlorinated fluorocarbons, N.O.S.

Chlorinated naphthalene, N.O.S.

Chlorinated phenol, N.O.S.

Chlornaphazin (Naphthalenamine, N,N’-

bis(2-chlorethyl)-)

Chloroacetaldehyde (Acetaldehyde, chloro-)

Chloroalkyl ethers, N.O.S.

p-Chloroaniline (Benzenamine, 4-chloro-)

Chlorobenzene (Benzene, chloro-)

Chlorobenzilate (Benzeneacetic acid, 4-

chloro-α-(4-chlorophenyl)-α-hydroxy-,

ethyl ester)

p-Chloro-m-cresol (Phenol, 4-chloro-3-

methyl)

2-Chloroethyl vinyl ether (Ethene, (2-

chloroethoxy)-)

Chloroform (Methane, trichloro-)

Chloromethyl methyl ether (Methane,

chloromethoxy-)

β-Chloronapthalene (Naphthalene, 2-chloro-)

o-Chlorophenol (Phenol, 2-chloro-)

1-(o-Chlorophenyl)thiourea (Thiourea, (2-

chlorophenyl-))

3-Chloropropionitrile (Propanenitrile, 3-

chloro-)

Chromium and compounds, N.O.S.

Chrysene

Citrus red No. 2 (2-Naphthalenol, 1-[(2,5-

dimethoxyphenyl)azo]-)

Coal tar creosote

Copper cyanide (CuCN)

Creosote

Cresol (Chresylic acid) (Phenol, methyl-)

Crotonaldehyde (2-Butenal)

Cyanides (soluble salts and complexes),

N.O.S.

Cyanogen (Ethanedinitrile)

Cyanogen bromide ((CN)Br)

Cyanogen chloride ((CN)Cl)

Cycasin (beta-D-Glucopyranoside, (methylONN-azoxy)methyl)

2-Cyclohexyl-4,6-dinitrophenol (Phenol, 2-

cyclohexyl-4,6-dinitro-)

Cyclophosphamide (2H-1,3,2-

Oxazaphosphorin-2-amine,N,N-bis(2-

chloroethyl)

tetrahydro-,2-oxide)

2,4-D and salts and esters (Acetic acid, (2,4-

dichlorophenoxy)-)

Daunomycin (5,12-Naphthacenedione,8-

acetyl-10-[(3-amino-2,3,6-trideoxy-α-Llyxohexopyranosyl)oxy]-7,8,9,10-tetrahydro6,8,11-trihydroxy-1-methoxy-,(8S-cis))

DDD (Benzene, 1,1’-(2,2-

dichloroethylidene)bis[4-chloro-)

DDE (Benzene, 1,1-(dichloroethylidene)bis[4-

chloro-)

DDT (Benzene, 1,1’-(2,2,2-

trichloroethlyidene)bis[4-chloro-)

Diallate (Carbomothioic acid, bis(1-

methylethyl)-,S-(2,3-dichloro-2-propenyl)

ester)

Dibenz[a,h]acridine

Dibenz[a,j]acridine

Dibenz[a,h]anthracene

7H-Dibenzo[c,g]carbazole

Dibenzo[a,e]pyrene (Naphtho[1,2,4,5-

def)crysene)

Dibenzo[a,h]pyrene (Dibenzo[b,def]crysene)

Dibenzo[a,i]pyrene (Benzo[rst]pentaphene)

1,2-Dibromo-3-chloropropane (Propane, 1,2-

dibromo-3-chloro-)

Dibutylphthalate (1,2-Benzenedicarboxylic

acid, dibutyl ester)

o-Dichlorobenzene (Benzene, 1,2-dichloro-)

m-Dichlorobenzene (Benzene, 1,3-dichloro-)

p-Dichlorobenzene (Benzene, 1,4-dichloro-)

Dichlorobenzene, N.O.S. (Benzene; dichloro-

, N.O.S.)

3,3’-Dichlorobenzidine ([1,1’-Biphenyl]-4,4’-

diamine, 3,3’-dichloro-)

1,4-Dichloro-2-butene (2-Butene, 1,4-

dichloro-)

Dichlorodifluoromethane (Methane,

dichlorodifluoro-)

Dichloroethylene, N.O.S.

1,1-Dichloroethylene (Ethene, 1,1-dichloro-)

1,2-Dichloroethylene (Ethene, 1,2-dichloro-

,(E)-)

Dichloroethyl ether (Ethane, 1,1’-oxybis[2-

chloro-)

Dichloroisopropyl ether (Propane, 2,2’-

oxybis[2-chloro-)

Dichloromethoxy ethane (Ethane, 1,1’-

[methylenebis(oxy)bis[2-chloro-)

Dichloromethyl ether (Methane,

oxybis[chloro-)

2,4-Dichlorophenol (Phenol, 2,4-dichloro-)

2,6-Dichlorophenol (Phenol, 2,6-dichloro-)

Dichlorophenylarsine (Arsinous dichloride,

phenyl-)

Dichloropropane, N.O.S. (Propane,

dichloro-,)

Dichloropropanol, N.O.S. (Propanol,

dichloro-,)

Dichloropropene; N.O.S. (1-Propane,

dichloro-,)

1,3-Dichloropropene (1-Propene, 1,3-

dichloro-)

Dieldrin (2,7:3,6-Dimethanonaphth[2,3-

b]oxirene,3,4,5,6,9,9-hexachloro1a,2,2a,3,6,6a,7,7a,octahydro-

,(1aα,2β,2aα,3β,6β,6aα,7β,7aα)-)

1,2:3,4-Diepoxybutane (2,2’-Bioxirane)

Diethylarsine (Arsine, diethyl-)

1,4 Diethylene oxide (1,4-Dioxane)

Diethylhexyl phthalate (1,2-

Benzenedicarboxlyic acid, bis(2-ethylhexl)

ester)

N,N-Diethylhydrazine (Hydrazine, 1,2-

diethyl)

O,O-Diethyl S-methyl dithiophosphate

(Phosphorodithioic acid, O,O-diethyl Smethyl ester)

Diethyl-p-nitrophenyl phosphate (Phosphoric

acid, diethyl 4-nitrophenyl ester)

Diethyl phthalate (1,2-Benzenedicarboxylic

acid, diethyl ester)

O,O-Diethyl O-pyrazinyl phosphorothioate

(Phosphorothioic acid, O,O-diethyl Opyrazinyl ester)

Diethylstilbesterol (Phenol, 4,4’-(1,2-diethyl1,2-ethenediyl)bis-,(E)-)

Dihydrosafrole (1,3-Benxodioxole, 5-propyl-)

Diisopropylfluorophosphate (DFP)

(Phosphorofluoridic acid, bis(1-methyl

ethyl) ester)

Dimethoate (Phosphorodithioic acid, O,Odimethyl S-[2-(methylamino) 2-oxoethyl]

ester)

3,3’-Dimethoxybenzidine ([1,1’-Biphenyl]-

4,4’-diamine, 3,3’-dimethoxy-)

p-Dimethylaminoazobenzene (Benzenamine,

N,N-dimethyl-4-(phenylazo)-)

7,12-Dimethylbenz[a]anthracene

(Benz[a]anthracene, 7,12-dimethyl-)

3,3’-Dimethylbenzidine ([1,1’-Biphenyl]-4,4’-

diamine, 3,3’-dimethyl-)

Dimethylcarbamoyl chloride (carbamic

chloride, dimethyl-)

1,1-Dimethylhydrazine (Hydrazine, 1,1-

dimethyl-)

1,2-Dimethylhydrazine (Hydrazine, 1,2-

dimethyl-)

α,α-Dimethylphenethylamine

(Benzeneethanamine, α,α-dimethyl-)

2,4-Dimethylphenol (Phenol, 2,4-dimethyl-)

Dimethylphthalate (1,2-Benzenedicarboxylic

acid, dimethyl ester)

Dimethyl sulfate (Sulfuric acid, dimethyl

ester)

Dinitrobenzene, N.O.S. (Benzene, dinitro-)

4,6-Dinitro-o-cresol and salts (Phenol, 2-

methyl-4,6-dinitro-)

2,4-Dinitrophenol (Phenol, 2,4-dinitro-)

2,4-Dinitrotoluene (Benzene, 1-methyl-2,4-

dinitro-)

2,6-Dinitrotoluene (Benzene, 2-methyl-1,3-

dinitro-)

Dinoseb (Phenol, 2-(1-methylpropyl)-4,6-

dinitro-)

Di-n-octyl phthalate (1,2-

Benzenedicarboxylic acid, dioctyl ester)

1,4-Dioxane (1,4-Diethyleneoxide)

Diphenylamine (Benzenamine, N-phenyl-)
2870 Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations

1,2-Diphenylhydrazine (Hydrazine, 1,2-

diphenyl-)

Di-n-propylnitrosamine (1-Propanamine,Nnitroso-N-propyl-)

Disulfoton (Phosphorodithioic acid, O,Odiethyl S-[2-(ethylthio)ethyl] ester)

Dithiobiuret (Thioimidodicarbonic diamide

[(H2N)C(S)]2NH)

Endosulfan (6,9,Methano-2,4,3-

benzodioxathiepin,6,7,8,9,10,10-

hexachloro-1,5,5a,6,9,9ahexahydro,3-

oxide)

Endothall (7-Oxabicyclo[2.2.1]heptane-2,3-

dicarboxylic acid)

Endrin and metabolites (2,7:3,6-

Dimethanonaphth[2,3-

b]oxirene,3,4,5,6,9,9-

hexachloro1a,2,2a,3,6,6a,7,7a-octahydro,(1aα,2β,2aβ,3α,6α,6aβ,7β,7aα)-)

Epichlorohydrin (Oxirane, (chloromethyl)-)

Epinephrine (1,2-Benzenediol,4-[1-hydroxy2-(methylamino)ethyl]-,(R)-,)

Ethyl carbamate (urethane) (Carbamic acid,

ethyl ester)

Ethyl cyanide (propanenitrile)

Ethylenebisdithiocarbamic acid, salts and

esters (Carbamodithioic acid, 1,2-

Ethanediylbis-)

Ethylene dibromide (1,2-Dibromoethane)

Ethylene dichloride (1,2-Dichloroethane)

Ethylene glycol monoethyl ether (Ethanol, 2-

ethoxy-)

Ethyleneimine (Aziridine)

Ethylene oxide (Oxirane)

Ethylenethiourea (2-Imidazolidinethione)

Ethylidene dichloride (Ethane, 1,1-

Dichloro-)

Ethyl methacrylate (2-Propenoic acid, 2-

methyl-, ethyl ester)

Ethylmethane sulfonate (Methanesulfonic

acid, ethyl ester)

Famphur (Phosphorothioic acid, O-[4-

[(dimethylamino)sulphonyl]phenyl] O,Odimethyl ester)

Fluoranthene

Fluorine

Fluoroacetamide (Acetamide, 2-fluoro-)

Fluoroacetic acid, sodium salt (Acetic acid,

fluoro-, sodium salt)

Formaldehyde (Methylene oxide)

Formic acid (Methanoic acid)

Glycidylaldehyde (Oxiranecarboxyaldehyde)

Halomethane, N.O.S.

Heptachlor (4,7-Methano-1H-indene,

1,4,5,6,7,8,8-heptachloro-3a,4,7,7atetrahydro-)

Heptachlor epoxide (α, β, and γ isomers) (2,5-

Methano-2H-indeno[1,2-b]-oxirene,

2,3,4,5,6,7,7-heptachloro-1a,1b,5,5a,6,6ahexa-hydro-,(1aα,1bβ,2α,5α,5aβ,6β,6aα)-)

Hexachlorobenzene (Benzene, hexachloro-)

Hexachlorobutadiene (1,3-Butadiene,

1,1,2,3,4,4-hexachloro-)

Hexachlorocyclopentadiene (1,3-

Cyclopentadiene, 1,2,3,4,5,5-hexachloro-)

Hexachlorodibenzofurans

Heptachlorodibenzo-p-dioxins

Hexachloroethane (Ethane, hexachloro-)

Hexachlorophene (phenol, 2,2’-

Methylenebis[3,4,6-trichloro-)

Hexachloropropene (1-Propene, 1,1,2,3,3,3-

hexachloro-)

Hexaethyl tetraphosphate (Tetraphosphoric

acid, hexaethyl ester)

Hydrazine

Hydrocyanic acid

Hydrofluoric acid

Hydrogen sulfide (H2S)

Indeno(1,2,3-cd)pyrene

Isobutyl alcohol (1-Propanol, 2-methyl-)

Isodrin (1,4,5,8-Dimethanonaphthalene,

1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8ahexahydro, (1α,4α,4aβ,5β,8β,8aβ)-)

Isosafrole (1,3-Benzodioxole, 5-(1-propenyl)-)

Kepone (1,3,4-Metheno-2Hcyclobuta[cd]pentalen-2-one,

1,1a,3,3a,4,5,5,5a,5b,6-

decachlorooctahydro-)

Lasiocarpine (2-Butenoic acid, 2-methyl-,7-

[[2,3-dihydroxy-2-(1-methoxyethyl)-3-

methyl-1-oxobutoxy]methyl]-2,3,5,7atetrahydro-1H-pyrrolizin-l-yl ester)

Lead and compounds, N.O.S.

Lead acetate (Acetic acid, lead(2+) salt)

Lead phosphate (Phosphoric acid, lead(2+)

salt(2:3))

Lead subacetate (Lead, bis(acetatoO)tetrahydroxytri-)

Lindane (Clohexane, 1,2,3,4,5,6-hexachloro-,

(1α,2α,3β,4α,5α,6β)-)

Maleic anhydride (2,5-Furandione)

Maleic hydrazide (3,6-Pyridazinedione, 1,2-

dihydro-)

Malononitrile (Propanedinitrile)

Melphalan (L-Phenylalanine, 4-[bis(2-

chloroethyl)aminol]-)

Mercury and compounds, N.O.S.

Mercury fulminate (Fulminic acid,

mercury(2+) salt)

Methacrylonitrile (2-Propenenitrile, 2-

methyl-)

Methapyrilene (1,2-Ethanediamine, N,Ndimethyl-N’-2-pyridinyl-N’-(2-

thienylmethyl)-)

Metholmyl (Ethamidothioic acid, N-

[[(methylamino)carbonyl]oxy]thio-, methyl

ester)

Methoxychlor (Benzene, 1,1’-(2,2,2-

trichloroethylidene)bis[4-methoxy-)

Methyl bromide (Methane, bromo-)

Methyl chloride (Methane, chloro-)

Methyl chlorocarbonate (Carbonchloridic

acid, methyl ester)

Methyl chloroform (Ethane, 1,1,1-trichloro-)

3-Methylcholanthrene (Benz[j]aceanthrylene,

1,2-dihydro-3-methyl-)

4,4’-Methylenebis(2-chloroaniline)

(Benzenamine, 4,4’-methylenebis(2-

chloro-)

Methylene bromide (Methane, dibromo-)

Methylene chloride (Methane, dichloro-)

Methyl ethyl ketone (MEK) (2-Butanone)

Methyl ethyl ketone peroxide (2-Butanone,

peroxide)

Methyl hydrazine (Hydrazine, methyl-)

Methyl iodide (Methane, iodo-)

Methyl isocyanate (Methane, isocyanato-)

2-Methyllactonitrile (Propanenitrile, 2-

hydroxy-2-methyl-)

Methyl methacrylate (2-Propenoic acid, 2-

methyl-, methyl ester)

Methyl methanesulfonate (Methanesulfonic

acid, methyl ester)

Methyl parathion (Phosphorothioic acid,

O,O-dimethyl O-(4-nitrophenyl) ester)

Methylthiouracil (4(1H)Pyrimidinone, 2,3-

dihydro-6-methyl-2-thioxo-)

Mitomycin C (Azirino[2’,3’:3,4]pyrrolo[1,2-

a]indole-4,7-dione,6-amino-8-

[[(aminocarbonyl) oxy]methyl]-

1,1a,2,8,8a,8b-hexahydro-8a-methoxy-5-

methy-, [1aS-(1aα,8β,8aα,8bα)]-)

MNNG (Guanidine, N-methyl-N’-nitro-Nnitroso-)

Mustard gas (Ethane, 1,1’-thiobis[2-chloro-)

Naphthalene

1,4-Naphthoquinone (1,4-Naphthalenedione)

α-Naphthalenamine (1-Naphthylamine)

β-Naphthalenamine (2-Naphthylamine)

α-Naphthylthiourea (Thiourea, 1-

naphthalenyl-)

Nickel and compounds, N.O.S.

Nickel carbonyl (Ni(CO)4 (T-4)-)

Nickel cyanide (Ni(CN)2)

Nicotine and salts (Pyridine, 3-(1-methyl-2-

pyrrolidinyl)-, (S)-)

Nitric oxide (Nitrogen oxide NO)

p-Nitroaniline (Benzenamine, 4-nitro-)

Nitrobenzene (Benzene, nitro-)

Nitrogen dioxide (Nitrogen oxide NO2)

Nitrogen mustard, and hydrochloride salt

(Ethanamine, 2-chloro-N-(2-chloroethyl)-Nmethyl-)

Nitrogen mustard N-oxide and hydrochloride

salt (Ethanamine, 2chloro-N-(2-

chloroethyl)N-methyl-, N-oxide)

Nitroglycerin (1,2,3-Propanetriol, trinitrate)

p-Nitrophenol (Phenol, 4-nitro-)

2-Nitropropane (Propane, 2-nitro-)

Nitrosamines, N.O.S.

N-Nitrosodi-n-butylamine (l-Butanamine, Nbutyl-N-nitroso-)

N-Nitrosodiethanolamine (Ethanol, 2,2’-

(nitrosoimino)bis-)

N-Nitrosodiethylamine (Ethanamine, Nethyl-N-nitroso-1)

N-Nitrosodimethylamine (Methanamine, Nmethyl-N-nitroso-)

N-Nitroso-N-ethylurea (Urea, N-ethyl-Nnitroso-)

N-Nitrosomethylethylamine (Ethanamine, Nmethyl-N-nitroso-)

N-Nitroso-N-methylurea (Urea, N-methyl-Nnitroso-)

N-Nitroso-N-methylurethane (Carbamic acid,

methylnitroso-, ethyl ester)

N-Nitrosomethylvinylamine (Vinylamine, Nmethyl-N-nitroso-)

N-Nitrosomorpholine (Morpholine,

4-nitroso-)

N-Nitrosonornicotine (Pyridine, 3-(1-nitroso2-pyrrolidinyl)-, (S)-)

N-Nitrosopiperidine (Piperidine, 1-nitroso-)

Nitrosopyrrolidine (Pyrrolidine, 1-nitroso-)

N-Nitrososarcosine (Glycine, N-methyl-Nnitroso-)

5-Nitro-o-toluidine (Benzenamine, 2-methyl5-nitro-)

Octamethylpyrophosphoramide

(Diphosphoramide, octamethyl-)

Osmium tetroxide (Osmium oxide OsO4, (T4)-)

Paraldehyde (1,3,5-Trioxane, 2,4,6-tri

methyl-)

Parathion (Phosphorothioic acid, O,O-diethyl

O-(4-nitrophenyl) ester)

Pentachlorobenzene (Benzene, pentachloro-)

Pentachlorodibenzo-p-dioxins

Pentachlorodibenzofurans

Pentachloroethane (Ethane, pentachloro-)

Pentachloronitrobenzene (PCNB) (Benzene,

pentachloronitro-)

Pentachlorophenol (Phenol, pentachloro-)

Phenacetin (Acetamide, N-(4-ethoxyphenyl)-)

Phenol

Phenylenediamine (Benzenediamine)

Phenylmercury acetate (Mercury, (acetatoO)phenyl-)
Federal Register / Vol. 60, No. 7 / Wednesday, January 11, 1995 / Rules and Regulations 2871

Phenylthiourea (Thiourea, phenyl-)

Phosgene (Carbonic dichloride)

Phosphine

Phorate (Phosphorodithioic acid, O,O-diethyl

S-[(ethylthiomethyl] ester)

Phthalic acid esters, N.O.S.

Phthalic anhydride (1,3-isobenzofurandione)

2-Picoline (Pyridine, 2-methyl-)

Polychlorinated biphenyls, N.O.S.

Potassium cyanide (K(CN))

Potassium silver cyanide (Argentate(l-),

bis(cyano-C)-, potassium)

Pronamide (Benzamide, 3,5-dichloro-N-(1,1-

dimethyl-2-propynyl)-)

1,3-Propane sultone (1,2-Oxathiolane, 2,2-

dioxide)

n-Propylamine (1-Propanamine)

Propargyl alcohol (2-Propyn-1-ol)

Propylene dichloride (Propane, 1,2-

dichloro-)

1,2-Propylenimine (Aziridine, 2-methyl-)

Propylthiouracil (4(1H)-Pyrimidinone, 2,3-

dihydro-6-propyl-2-thioxo-)

Pyridine

Reserpinen (Yohimban-16-carboxylic acid,

11,17-dimethoxy-18-[(3,4,5-

trimethoxybenzoyl)oxy]-smethyl ester,

(3β,16 β,17α,18β,20α)-)

Resorcinol (1,3-Benzenediol)

Saccharin and salts (1,2-Benzisothiazol3(2H)-one, 1,1-dioxide)

Safrole (1,3-Benzodioxole, 5-(2-propenyl)-)

Selenium and compounds, N.O.S.

Selenium dioxide (Selenious acid)

Selenium sulfide (SeS2)

Selenourea

Silver and compounds, N.O.S.

Silver cyanide (Silver cyanide Ag(CN))

Silvex (Propanoic acid, 2-(2,4,5-

trichlorophen

oxy)-)

Sodium cyanide (Sodium cyanide Na(CN))

Streptozotocin (D-Glucose, 2-deoxy-2-

[[methylnitrosoamino)carbonyl]amino]-)

Strychnine and salts (Strychnidin-10-one)

TCDD (Dibenzo[b,e][1,4]dioxin, 2,3,7,8-

tetrachloro-)

1,2,4,5-Tetrachlorobenzene (Benzene, 1,2,4,5-

tetrachloro-)

Tetrachlorodibenzo-p-dioxins

Tetrachlorodibenxofurans

Tetrachloroethane, N.O.S. (Ethane,

tetrachloro-, N.O.S.)

1,1,1,2-Tetrachloroethane (Ethane, 1,1,1,2-

tetrachloro-)

1,1,2,2-Tetrachloroethane (Ethane, 1,1,2,2-

tetrachloro-)

Tetrachloroethylene (Ethene, tetrachloro-)

2,3,4,6-Tetrachlorophenol (Phenol, 2,3,4,6-

tetrachloro-)

Tetraethyldithiopyrophosphate

(Thiodiphosphoric acid, tetraethyl ester)

Tetraethyl lead (Plumbane, tetraethyl-)

Tetraethyl pyrophosphate (Diphosphoric

acid, tetraethyl ester)

Tetranitromethane (Methane, tetranitro-)

Thallium and compounds, N.O.S.

Thallic oxide (Thallium oxide Tl2O3)

Thallium (I) acetate (Acetic acid, thallium

(1+) salt)

Thallium (I) carbonate (Carbonic acid,

dithallium (1+) salt)

Thallium (I) chloride (Thallium chloride

TlCl)

Thallium (I) nitrate (Nitric acid, thallium (1+)

salt)

Thallium selenite (Selenius acid, dithallium

(1+) salt)

Thallium (I) sulfate (Sulfuric acid, thallium

(1+) salt)

Thioacetamide (Ethanethioamide)

3,Thiofanox (2-Butanone, 3,3-dimethyl-1-

(methylthio)-, O-[(methylamino)carbonyl]

oxime)

Thiomethanol (Methanethiol)

Thiophenol (Benzenethiol)

Thiosemicarbazide

(Hydrazinecarbothioamide)

Thiourea

Thiram (Thioperoxydicarbonic diamide

[(H2N)C(S)]2S2, tetramethyl-)

Toluene (Benzene, methyl-)

Toluenediamine (Benzenediamine, armethyl-)

Toluene-2,4-diamine (1,3-Benzenediamine,

4-methyl-)

Toluene-2,6-diamine (1,3-Benzenediamine,

2-methyl-)

Toluene-3,4-diamine (1,2-Benzenediamine,

4-methyl-)

Toluene diisocyanate (Benzene, 1,3-

diisocyanatomethyl-)

o-Toluidine (Benzenamine, 2-methyl-)

o-Toluidine hydrochloride (Benzenamine, 2-

methyl-, hydrochloride)

p-Toluidine (Benzenamine, 4-methyl-)

Toxaphene

1,2,4-Trichlorobenzene (Benzene, 1,2,4-

trichloro-)

1,1,2-Trichloroethane (Ethane, 1,1,2-

trichloro-)

Trichloroethylene (Ethene,trichloro-)

Trichloromethanethiol (Methanethiol,

trichloro-)

Trichloromonofluoromethane (Methane,

trichlorofluoro-)

2,4,5-Trichlorophenol (Phenol, 2,4,5-

trichloro-)

2,4,6-Trichlorophenol (Phenol, 2,4,6-

trichloro-)

2,4,5-T (Acetic acid, 2,4,5- trichlorophenoxy-)

Trichloropropane, N.O.S.

1,2,3-Trichloropropane (Propane, 1,2,3-

trichloro-)

O,O,O-Triethyl phosphorothioate

(Phosphorothioic acid, O,O,O-triethyl

ester)

Trinitrobenzene (Benzene, 1,3,5-trinitro-)

Tris(1-aziridinyl)phosphine sulfide

(Aziridine,

1,1’,1’’phosphinothioylidynetris-))

Tris(2,3-dibromopropyl) phosphate (1-

Propanol, 2,3-dibromo-, phosphate (3:1))

Trypan blue (2,7-Naphthalendisulfonic acid,

3,3’-[(3,3’-dimethyl[1,1’-biphenyl]-4,4’-

diyl)bis(azo)]bis(5-amino-4-hydroxy-,

tetrasodium salt)

Uracil mustard (2,4-(1H,3H)-

Pyrimidinedione, 5-[bis(2-

chloroethyl)amino]-)

Vanadium pentoxide (Vanadium oxide V2O5)

Vinyl chloride (Ethene, chloro-)

Wayfarin (2H-1-Benzopyran-2-one, 4-

hydroxy-3-(3-oxo-1-phenlybutyl)-)

Zinc cyanide (Zn(CN)2)

Zinc phosphide (Zn3P2)

[FR Doc. 95–546 Filed 1–10–95; 8:45 am]

BILLING CODE 6560–50–P