[Federal Register Volume 66, Number 20 (Tuesday, January 30, 2001)]
[Pages 8234-8236]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-2570]




Underground Injection Control Program: Substantial Modification 
to an Existing State-Administered Underground Injection Control Program

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice; request for public comment on a substantial 
modification to the Wyoming 1422 underground injection control program.


SUMMARY: The Safe Drinking Water Act (SDWA) establishes the Underground 
Injection Control (UIC) Program, which is designed to protect present 
and future underground sources of drinking water (USDWs) and to prevent 
underground injection through wells that may endanger these drinking 
water sources. The SDWA provides for states to apply for and receive 
approval from the Environmental Protection Agency (EPA) to administer 
their own UIC programs, if the State regulations and statutes meet 
EPA's minimum requirements as specified in 40 CFR parts 144, 145, and 
146 or the ``protective'' standard specified in section 1425 of the 
SDWA for oil and gas related wells. One of these requirements specified 
in 40 CFR 144.7 is the identification of USDWs. If an aquifer meets the 
definition of a USDW as stated in 40 CFR 144.3, injection into it 
through a Class I, II, or III injection well can occur only if the 
aquifer is exempted. Exemption from classification as a USDW can take 
place only if it is exempted from the classification as a USDW 
according to the criteria in 40 CFR 146.4. Therefore, injection through 
a Class I, II, or III injection well into any aquifer that meets the 
classification as a USDW requires a demonstration that the aquifer is 
not currently serving a drinking water system and is not expected to do 
so in the future. Certain exemptions are considered substantial program 
revisions. Once the State program receives final approval, subsequent 
modifications to the programs can be requested by the State and 
accomplished through the specifications under 40 CFR 145.32. Upon 
receiving a request for modification of a State program, EPA determines 
if the requested modification is ``substantial'' or ``non-
substantial.'' A request for an Aquifer Exemption is one type of 
program modification that can be requested by the State. An Aquifer 
Exemption request often accompanies a Draft Permit for an injection 
well that

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will inject into a USDW that can be proven to meet criteria specified 
in 40 CFR 146.4. If the Aquifer Exemption is considered a ``non-
substantial'' modification to the existing State program, then it can 
be evaluated and approved or disapproved by the EPA Regional 
Administrator. However, if the aquifer proposed for exemption contains 
formation fluids with less than 3,000 mg/l Total Dissolved Solids (TDS) 
which is related to any Class I well or is not related to action on a 
permit (except in the case of rule authorized enhanced recovery 
operations in oil fields), then the Aquifer Exemption represents a 
``substantial'' modification to the State program. In this case, 
according to 40 CFR 145.32, the proposed program revision shall be 
published in the Federal Register to provide the public an opportunity 
to comment for a period of at least 30 days. The authority to approve 
or disapprove the proposed change lies with the EPA Administrator. The 
proposed substantial revision to the Wyoming 1422 UIC program for which 
public comments are being solicited is a request for the exemption of 
approximately 1 square mile of the Lance Formation at an approximate 
depth of 3,800 to 6,500 feet below ground surface surrounding two non-
hazardous Class I injection wells in the Powder River Basin within 
Johnson County, Wyoming.
    Public comments are encouraged and a public hearing will be held 
upon request. A request for a public hearing should be made in writing 
and should state the nature of the issues proposed to be raised at the 
hearing. A public hearing will be held only if significant interest is 

DATES: EPA must receive public comment, in writing, on the proposed 
modification of the Wyoming 1422 program by March 1, 2001.

ADDRESSES: Send written comments to Valois Shea, Ground Water Unit (8P-
W-GW), Environmental Protection Agency, Region VIII, 999 18th Street, 
Suite 300, Denver, Colorado, 80202-2466, by the deadlines provided 
above. Copies of the application and pertinent materials are available 
for review by the public between 8:30 a.m. and 4:00 p.m. Monday through 
Friday at the following locations: Environmental Protection Agency, 
Region VIII, Ground Water Unit, 4th Floor North Terrace, 999 18th 
Street, Denver, CO 80202-2466; and Department of Environmental Quality, 
Herschler Building, 122 West 25th Street, Cheyenne, WY 82002.

GW, 999 18th Street, Suite 300, Denver, CO 80202-2466, (303) 312-6276.


I. Introduction

    On September 25, 2000, COGEMA Mining, Inc., (COGEMA) and the 
Wyoming Department of Environmental Quality (WDEQ) submitted to EPA a 
request to grant an Aquifer Exemption for the Lance Formation in the 
areas contained within Township 44 North, Range 76 West, 6th P.M. , 
SW\1/4\ NW\1/4\ Section 5, SE\1/4\ NW\1/4\ Section 5, SW\1/4\ Section 
5, NE\1/4\ Section 7, NW\1/4\ SE\1/4\ Section 7, NE\1/4\ SE\1/4\ 
Section 7, NW\1/4\ NW\1/4\ Section 8, NE\1/4\ NW\1/4\ Section 8, SW\1/
4\ NW\1/4\ Section 8, and NW\1/4\ SW\1/4\ Section 8, surrounding two 
Class I Non-Hazardous deep injection wells, the COGEMA DW No. 3 and the 
COGEMA DW No. 2, in Johnson County, WY. The total area of the Lance 
Formation included in the proposed exemption is approximately 1 square 
mile. The proposed injection intervals are approximately 3,800 to 6,500 
feet in depth below ground surface for each well. The proposed 
injection interval is based on the depth of the Lance Formation 
intersected by adjacent Class I Non-Hazardous deep injection well, 
COGEMA DW No. 1. A similar exemption of a portion of the Lance 
Formation was proposed for the COGEMA DW No. 1 in the Federal Register 
on August 27, 1998 (63 FR 45810). The notice also solicited public 
comment of the proposed action. No public comments were received, and 
the final notice of the Aquifer Exemption was included in the Federal 
Register on March 26, 1999 (64 FR 14799).
    The Lance Formation fluids contain less than 3,000 mg/l Total 
Dissolved Solids (TDS), dictating that this Aquifer Exemption be a 
substantial revision of the Wyoming Underground Injection Control (UIC) 
program approved under section 1422 of the Safe Drinking Water Act. 
Criteria for classification of a program revision as substantial or 
not, are in UIC Guidance #34, Guidance for Review and Approval of State 
UIC Programs and Revisions to Approved State Programs. The procedures 
to follow to approve or disapprove substantial program revisions in the 
UIC program are in Sec. 145.32 and in UIC guidance #34. The aquifer 
proposed for exemption has been determined by WDEQ to be too deep to be 
considered as an economically feasible source of drinking water. EPA 
has examined the Aquifer Exemption request, the accompanying 
information, and responses from WDEQ and COGEMA to EPA requests for 
additional supporting information, and, for reasons described herein, 
recommends approval of this request to exempt the designated portions 
of the Lance Formation from classification as a USDW.

II. Background

    COGEMA operates the Christensen Ranch in-situ leaching uranium mine 
within the Wasatch Sandstone Formation in Johnson and Campbell 
Counties, WY. The Wasatch Formation overlies the Lance Formation by 
about 2,600 feet at the mine site. The mining operation has comprised 
five well fields to date. The operation has reached the phase where 
large scale restoration of the groundwater within all the well fields 
is required to close the operation. Two Class I Non-Hazardous deep 
injection wells are currently being used to inject the above-mentioned 
waste stream into previously exempted portions of the Lance Formation. 
However, with the current disposal capacity of the two existing wells, 
the rate of the restoration process is limited. A large portion of the 
mined aquifer is on ``standby'' until either (a) the disposal capacity 
can be increased by the addition of two new wells, or (b) the 
restoration process is completed in other mined-out areas. The 
additional disposal rate capacity created by these two proposed wells 
will increase the rate of the restoration process significantly, 
restoring the Wasatch Formation water quality to its class of use 
standards two years sooner than without the two additional wells. The 
mined areas on ``standby'' awaiting restoration must require a 
continuous bleed-off because a negative pressure regime must be 
maintained in order to keep the underground water flow directed into 
the mining area to prevent the contamination of adjacent areas of the 
aquifers (the Wasatch Formation). To maintain the negative pressure, 
water must continuously be pumped out of the mined areas in standby 
mode. The additional two years required for complete restoration 
without the two new wells would result in approximately 31 million 
additional gallons of waste stream to be disposed of that could be 
avoided by the construction of two new wells, increasing the disposal 
    Groundwater restoration is conducted to return the groundwater 
affected by mining to its baseline condition or to a condition 
consistent with its pre-mining or potential use upon completion of 
mining activities. After the restoration process is completed, the 
concentrations of contaminants are reduced to levels below drinking 
water standards. For the successful restoration of the

[[Page 8236]]

groundwater quality within the mined-out areas of the Wasatch 
Formation, a wastewater disposal capacity of 300 to 500 gallons per 
minute (gpm) will be required over the next 6 years.

III. Injectate

    The injectate will consist of operational bleed streams from 
commercial in-situ leaching uranium mining operations as well as fluids 
from the restoration of the aquifer. The constituents on the injectate 
include the following process and restoration bleed streams: normal 
overproduction (well field bleed) streams, yellow cake wash water, 
laboratory wastewater, reverse osmosis brine, and groundwater sweep 
solutions. The bleed streams are defined as non-hazardous, and as 
beneficiation wastes exempt from regulation under the Resource 
Conservation and Recovery Act as stipulated by the Bevill Amendment (40 
CFR 261.4(b)(7)).

IV. Basis for Approval of Proposed Aquifer Exemption

    The information provided by COGEMA in the reports included in the 
docket adequately addresses the requirements of 40 CFR 146.4 supporting 
approval of the proposed Aquifer Exemption request for the Lance 

146. 4 Criteria for exempted aquifers

    An aquifer or a portion thereof which meets the criteria for an 
``underground source of drinking water'' in Sec. 146.3 may be 
determined under 40 CFR 144.8 to be an ``exempted aquifer'' if it 
meets the following criteria:
    (a) It does not currently serve as a source for drinking water;

    The nearest documented well completed in the Lance is over 24 miles 
to the west of the site. The exact use of this well is unknown, but 
appears to be associated with oil or gas development. Approximately 30 
miles to the west, the Lance outcrops to the surface and wells 
developed there are for livestock use. Where the Lance Formation occurs 
near the surface at the western edge of the Powder River Basin 30 miles 
southwest of the proposed exemption area, five wells jointly completed 
in the Lance and Fox Hills formations formerly served as public water 
supplies to the municipalities of Midwest and Edgerton, WY, until 1997. 
At that time, the wells were abandoned because of low water 
productivity (40 gpm sustainable flow) and the expense of treatment 
that would be required to continue using these wells as a public water 
supply. The towns of Midwest and Edgerton have determined that piping 
in pre-treated water 50 miles from Casper is more economically feasible 
than continuing operation of the wells completed in the Lance/Fox Hills 
formations, even at the relatively shallow depth of 1,500 to 2,000 
feet. Therefore, the Lance is no longer supplying water to a public 
drinking water system within 30 miles of the proposed Aquifer Exemption 

    (b) It cannot now and will not serve as a source of drinking 
water because:
    . . . (2) It is situated at a depth or location which makes 
recovery of water for drinking water purposes economically or 
technologically impractical.

    The depth of the Lance Formation within the Aquifer Exemption area 
ranges from 3,800 to 6,500 feet based on the information from the 
COGEMA DW No. 1 well. The Powder River Basin consists of a deep 
syncline. The Aquifer Exemption area occurs very near the deepest 
occurrence of the Lance Formation within this syncline.
    Alternatively, the Wasatch Formation overlies the Lance Formation 
in the Aquifer Exemption area and provides a more shallow, potential 
water supply source available for use in the area. According the USGS 
publications referenced by COGEMA, any water supply wells (aside from 
water flood wells related to oil production) in the proposed Aquifer 
Exemption area are completed in the Wasatch Formation. The Wasatch 
Formation is a high quality, prolific aquifer, located at approximately 
1,200 feet in depth or shallower throughout the Powder River Basin, 
including the proposed Aquifer Exemption area. The Wasatch Formation, 
alone, contains a volume of water that would supply a population of 
approximately 1.3 million people for 100 years. Given this abundant, 
shallow supply of high quality groundwater, it is reasonable to 
conclude that the deeper Lance Formation will never be required to 
provide a source of drinking water in the area of the Aquifer 
    COGEMA provided a cost evaluation for the capital costs and 
estimated operating costs for developing a private (50 gpm) and a 
public (750 gpm) drinking water well, including treatment costs based 
on the water quality analysis of samples collected from the Lance 
Formation as a water supply source within the Aquifer Exemption area. 
The costs to develop the Lance within the exemption area were compared 
with estimated costs to develop the Wasatch Formation as an alternative 
public water supply (at the 750 gpm rate). The incremental cost 
increase for using the Lance Formation water versus Wasatch Formation 
water as a drinking water source for the public water supply is 
approximately $3,691,250. The incremental increase in operations and 
maintenance cost of using the Lance water over the Wasatch water as a 
drinking water source would be $2.40/1,000 gallons.
    The Midwest-Edgerton public water supply scenario should be noted 
as the most compelling support for the approval of this Aquifer 
Exemption request and the feasibility of using the Lance Formation as a 
public water supply. The five wells were abandoned in favor of piping 
in an alternative water supply. The decision to abandon these wells was 
based on the economic impact of the need to treat the water and the low 
production rates of the wells, even though the costs of development had 
already been expended. Furthermore, the wells tapped shallower portions 
of the Lance Formation compared to the depth of the Lance within the 
proposed Aquifer Exemption area.
    In summary, the Lance Formation probably will never be considered 
to be an economically feasible source of drinking water in the area of 
the Aquifer Exemption because of the great depth, low water production 
capacity, and treatment costs that will be necessary based on the 
Midwest-Edgerton wells. The cost of developing the Lance Formation as a 
drinking water supply within the proposed Aquifer Exemption area is 
high compared to that of developing shallow, more prolific, and higher 
quality sources of drinking water, such as the Wasatch Formation. The 
Wasatch is better suited for development in this area as a source of 
drinking water due to higher producing capability, significantly better 
water quality, and no water treatment costs.

V. Regulatory Impact

    There will be no modification of regulations in the Wyoming DEQ 
Water Quality Rules and Regulations as a result of this proposed 
program modification. The Code of Federal Regulations 40 CFR part 147, 
subpart ZZ, which codifies the State of Wyoming UIC 1442 and 1445 
program within the Federal regulations, will be modified to include 
this program modification once approval has been granted by the EPA 

    Dated: January 11, 2001.
D. Edwin Hogle,
Director, Ground Water Program, Office of Partnerships and Regulatory 
Assistance, Region VIII.
[FR Doc. 01-2570 Filed 1-29-01; 8:45 am]