| (a) The area of review is the area surrounding an injection
well or a group of injection wells, for which the permit application
must detail the information required in Subchapter G of this chapter
(relating to Consideration Prior to Permit Issuance).
(1) The area of review for Class I wells, except those
wells authorized to inject only nonhazardous desalination concentrate
or nonhazardous drinking water treatment residuals, is an area determined
by a radius of 2 1/2 miles from the proposed or existing wellbore,
or the area within the cone of influence, whichever is greater.
(2) The area of review for those Class I wells authorized
to inject only nonhazardous desalination concentrate or nonhazardous
drinking water treatment residuals, is an area determined by a radius
of 1/4 mile from the proposed or existing wellbore, or the area within
the cone of influence, whichever is greater. Notwithstanding subsection
(c) of this section, if the area of review is determined by a mathematical
model pursuant to subsection (b) of this section, the permissible
radius is the result of such calculation even if it is less than 1/4
mile.
(3) The area of review for salt dome cavern disposal
wells and associated caverns, is the sum of the two following areas:
(A) an area determined by a radius of 2 1/2 miles from
the proposed or existing wellbore; and
(B) the greatest horizontal plane cross-sectional area
of the salt dome between land surface and a depth of 1,000 feet below
the projected floor of the proposed or existing salt dome cavern.
(4) The area of review for Class III wells, is the
project area plus a circumscribing area, a minimum of 1/4 mile, the
width of which is the lateral distance from the perimeter of the project
area, in which the pressures in the injection zone may cause the migration
of the injection and/or formation fluid into a Underground Sources
of Drinking Water.
(5) The area of review for Class V wells is an area
determined by a radius of at least 1/4 mile from the proposed or existing
wellbore.
(b) The computation of the cone of influence may be
based upon the parameters listed in the figure in this subsection
and should be calculated for an injection time period equal to the
expected life of the injection well or pattern. The following modified
Theis equation illustrates one form which the mathematical model may
take:
Attached Graphic
(c) After an appropriate review, the commission may
modify the area of review. In no event shall the boundary of an area
of review be less than 2 1/2 miles for Class I wells, except those
wells authorized to inject only nonhazardous desalination concentrate
or nonhazardous drinking water treatment residuals, or 1/4 mile for
Class I wells authorized to inject only nonhazardous desalination
concentrate or nonhazardous drinking water treatment residuals, or
1/4 mile from any other injection well covered by the appropriate
authorization. The following factors are to be included in the review:
(1) Chemistry of injection and formation fluids;
(2) Hydrogeology;
(3) Population and its dependence on ground water use;
and
(4) Historical practices in the area.
(d) The executive director may require an owner or
operator of an existing injection well to submit any reasonably available
information regarding the area of review, if the information would
aid a review for the prevention or correction of freshwater pollution.
|
| Source Note: The provisions of this §331.42 adopted to be effective May 13, 1986, 11 TexReg 1982; amended to be effective July 5, 1989, 14 TexReg 3047; amended to be effective June 22, 1992, 17 TexReg 4097; amended to be effective April 28, 1997, 22 TexReg 3526; amended to be effective November 23, 2000, 25 TexReg 11433; amended to be effective July 10, 2008, 33 TexReg 5342; amended to be effective August 16, 2012, 37 TexReg 6078 |
