[Federal Register Volume 63, Number 166 (Thursday, August 27, 1998)]
[Pages 45810-45812]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-22897]




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

AGENCY: Environmental Protection Agency (EPA).

ACTION: 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 Part 144, 145, and 
146 or the ``protective'' standard specified in Sec. 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 is a USDW, 
injection into it can only occur if it is exempted from this 
classification because it is not serving a drinking water system and is 
not expected to do so in the future. Therefore, injection into any 
aquifer that meets the classification as a USDW can only take place if 
it is exempted from the classification as a USDW. Criteria for 
exempting aquifers is in Title 40 Sec. 146.4. 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 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 
0.04 square miles 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 September 28, 1998.

ADDRESSES: Send written comments to Valois Shea-Albin, Ground Water 
Unit (8P-W-GW), Environmental Protection Agency, Region VIII, 999 18th 
Street, Suite 500, 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.

[[Page 45811]]

Monday through Friday at the following locations:

Environmental Protection Agency, Region VIII, Ground Water Unit, 4th 
Floor Terrace, 999 18th Street, Denver, CO 80202-2466;
Department of Environmental Quality, Herschler Building, 122 West 25th 
Street, Cheyenne, WY 82002.

8P-W-GW, 999 18th Street, Suite 500, Denver, CO 80202, (303) 312-6276.


I. Introduction

    In October, 1997, COGEMA Mining, Inc., (COGEMA) and the Wyoming 
Department of Environmental Quality (WDEQ) requested that EPA grant an 
aquifer exemption for the Lance Formation in the areas encompassed by a 
radius of 1,320 feet surrounding two Class I non-hazardous injection 
wells, the COGEMA DW No. 1 and the Christensen 18-3, in Johnson County, 
WY. The proposed injection intervals are 3,818 to 6,320 feet and 4,009 
to 6,496 feet in depth below ground surface, respectively. The total 
area of the Lance Formation included in the proposed exemption is 0.4 
square miles.
    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 WY 1422 Underground Injection Control (UIC) 
program according procedures listed in UIC Guidance #34, Guidance for 
Review and Approval of State UIC Programs and Revisions to Approved 
State Programs. 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 concerns, and, for reasons described herein, recommends 
approval of this aquifer exemption.

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, two of which are currently producing, and 
three that have been mined out. The operation has reached the phase 
where large scale restoration of the groundwater within the mined out 
well fields is being conducted simultaneously with mineral extraction.
    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 groundwater 
quality within the mine-out areas of the Wasatch Formation, a 
wastewater disposal capacity of 300 to 500 gallons per minute (gpm) 
will be required over the next 18 years. Additionally, this type of 
operation requires the bleed-off of part of the fluid extracted in 
order to keep underground water flow into the mining area and prevent 
the contamination of adjacent aquifers in the Wasatch Formation. To 
date COGEMA has managed disposal of the fluid wastes under an NPDES 
permit to discharge to the surface, and through using evaporation ponds 
and limited non-hazardous Class I injection well disposal. The 
regulatory reduction of the selenium level permitted under NPDES will 
force COGEMA to discontinue surface discharge in the near future. After 
evaluating treatment methods to remove selenium from the wastewater in 
order to continue surface discharge, COGEMA found that reverse osmosis 
was the only method that consistently met the new selenium standard. 
The reverse osmosis process would treat 75% of the waste stream 
resulting in water of high enough quality for surface discharge. 
However, the high volume of remaining concentrated brine produced by 
the reverse osmosis process would still require the use of the two 
Class I injection wells and the aquifer exemption.
    COGEMA was previously granted an aquifer exemption for the above 
wells to inject into the Teckla, Parkman, and Teapot Formations 
(between 3,000 and 10,000 TDS, containing traces of oil and gas, and 
too deep to be an economically feasible source of drinking water). The 
original exempted interval for the COGEMA DW No. 1 was 7,500 to 8,470 
feet in depth and 7,631 to 8,604 feet in depth for the Christensen 18-
3. Trial injection into these formations revealed they were only 
capable of receiving less than 10 gpm instead of the 75 to 150 gpm 
anticipated from the evaluation of porosity logs. As a result, the 
company has now requested a permit modification to inject into the 
Lance Formation, an overlying geologic unit.

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, 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 
    Approximately 30 miles to the west, the Lance outcrops to the 
surface and wells developed there are for livestock use. 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, 30 miles southwest of the proposed exemption area 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, 
especially with the addition of some financial incentives, 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 
    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,

[[Page 45812]]

even though the costs of development had already been expended, and the 
wells tapped shallower portions of the Lance Formation compared to the 
proposed aquifer exemption area (page 13, April 17, 1998, COGEMA 
    The Lance Formation will probably never again be considered to be 
an economically feasible source of drinking water in the area of the 
proposed 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. Other regional 
aquifers, the Wasatch and Fort Union Formations for example, are 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.

VI. Regulatory Impact

    There will be no modification in regulations, either in the Code of 
Federal Regulations or Wyoming DEQ Water Quality Rules and Regulations, 
as a result of this proposed program modification.

    Dated: August 19, 1998.
D. Edwin Hogle,
Director, Groundwater Program, Office of Partnerships and Regulatory 
Assistance, Region VIII.
[FR Doc. 98-22897 Filed 8-26-98; 8:45 am]