|(a) Applicability. Subsections (b) - (m) of this section apply to Class I wells except for those Class I wells authorized to inject only nonhazardous desalination concentrate or nonhazardous drinking water treatment residuals. For Class I wells authorized to inject only nonhazardous desalination concentrate or nonhazardous drinking water treatment residuals only subsections (b) - (d) and (n) of this section apply. (b) All Class I wells shall be operated to prevent the movement of fluids that could result in the pollution of an underground source of drinking water (USDW) and to prevent leaks from the well into unauthorized zones. (c) Except during well stimulation, injection pressure at the wellhead shall not exceed a maximum which shall be calculated so as to assure that the pressure in the injection zone during injection does not initiate new fractures or propagate existing fractures in the injection zone, initiate new fractures or propagate existing fractures in the confining zone, or cause movement of fluid out of the injection zone that may pollute USDWs or surface water. (d) Injection between the outermost casing protecting USDWs and fresh or surface water and the wellbore is prohibited. (e) The annulus between the tubing and long string casing shall be filled with a non-corrosive or corrosion-inhibiting fluid approved by the commission. The annulus pressure shall be at least 100 psi greater than the injection tubing pressure to prevent leaks from the well into unauthorized zones and to detect well malfunctions, unless the executive director determines that such a requirement might harm the integrity of the well. (f) Monthly average and maximum instantaneous rates of injection, and annual and monthly volumes of injected fluids shall not exceed limits specified by the commission. (g) All gauges, pressure sensing, and recording devices shall be tested and calibrated quarterly. (h) Any chemical or physical characteristic of the injected fluids shall be maintained within specified permit limits for the protection of the injection well, associated facilities, and injection zone and to ensure proper operation of the facility. (i) The permittee shall notify the executive director before commencing any workover operation. The notification shall be in writing and shall include plans for the proposed work. Approval by the executive director shall be obtained before the permittee may begin the workover. The executive director may grant an exception to the prior written notification and permission requirements when immediate action is required to comply with subsection (b) of this section. (j) Pressure control equipment shall be installed and maintained during workovers which involve the removal of tubing. (k) For workovers or testing operations on hazardous waste disposal wells, all hazardous fluids shall be flushed from the wellbore with a nonhazardous fluid before conducting any portion of the operations which would result in the exposure of the hazardous wastes to the environment or the public. (l) The owner or operator shall maintain mechanical integrity of the injection well at all times. (m) The owner or operator of an injection well that has ceased operations for more than two years and is subject to §305.154(a)(7) of this title (relating to Standards) shall notify the executive director in writing 30 days prior to resuming operation of the well. (n) For Class I wells authorized to inject only nonhazardous desalination concentrate or nonhazardous drinking water treatment residuals, unless an alternative to a packer has been approved under §331.62(b)(3)(A) of this title (relating to Construction Standards), the annulus between the tubing and the long string of casings shall be filled with a fluid approved by the executive director and a pressure, also approved by the executive director, shall be maintained on the annulus.
|Source Note: The provisions of this §331.63 adopted to be effective May 13, 1986, 11 TexReg 1983; amended to be effective July 5, 1989, 14 TexReg 3047; amended to be effective August 19, 1991, 16 TexReg 4225; amended to be effective January 2, 1995, 19 TexReg 10099; amended to be effective April 28, 1997, 22 TexReg 3526; amended to be effective December 15, 1997, 22 TexReg 12059; amended to be effective July 10, 2008, 33 TexReg 5342