Section 4.151 - [Effective 7/1/2025] Design and Construction of Permitted Pits(a) Application. (1) Unless otherwise provided by permit, all permitted pits shall comply with the general construction requirements applicable to authorized pits in Division 3 of this subchapter (relating to Operations Authorized by Rule). (2) In addition to the information required by §4.128 of this title (relating to Design and Construction), the facility diagram submitted with the application shall include the following information: (A) the maximum length, width, and depth of the pit in feet; (B) the maximum depth of the pit below grade in feet; (C) the maximum and minimum height of walls or dikes above grade in feet; (D) the dimensions of the dikes including the width at the base, height, and slope; (E) the maximum volume of the pit in barrels and cubic yards; (F) the maximum volume of the pit minus the volume to maintain the required freeboard in barrels and cubic yards; (G) the volume of the pit below natural grade in barrels and cubic yards; (H) information on the pit liner type and thickness, installation methods, and manufacturer's specification sheets; (I) a plan view drawing of each pit, including all dimensions, and any trenches or structures used to separate and convey contact and non-contact stormwater; (J) two perpendicular, sectional views of each pit showing the bottom, sides, dikes, and natural grade, including all dimensions; and (K) the surface area and action leakage rate calculation for any pit with a leakage detection system, that is prepared and sealed by a professional engineer licensed in Texas. The action leakage rate calculations shall include: (i) all assumptions and dimensions used; (ii) the size of the pump and pipes that will be used in the leakage detection system; and (iii) calculations demonstrating that the system is designed to sufficiently withdraw and manage the expected leakage rate. (3) The permittee shall provide any other information necessary to address the operating requirements detailed in subsection (b) of this section. (b) Operating requirements. (1) Signage. The permittee shall post a sign at each permitted pit. The sign shall show the permit number in letters and numerals at least three inches in height. (2) Freeboard. Unless otherwise required by permit or rule, the permittee shall maintain all pits such that each pit maintains a freeboard of at least two feet plus the capacity to contain the volume of precipitation from a 25-year, 24-hour rainfall event. (3) Liners. (A) Equipment, machinery, waste, or other materials that could reasonably be expected to puncture, tear, or otherwise compromise the integrity of the liner shall not be used or placed in lined pits. (B) Unless the permit specifically provides otherwise, the liner for any permitted pit required to be lined shall comply with the general requirements for lining in Division 3 of this subchapter (relating to Operations Authorized by Rule), except that the thickness of a high-density polyethylene liner in a permitted pit shall be a minimum of 60 mil and, for any other type of synthetic liner, a minimum of 30 mil. (C) A brine pit permitted under this subchapter shall be constructed with a primary and secondary liner and a leakage detection system. (4) Additional requirements as determined by Director. Any pit permits issued pursuant to this subchapter may contain additional requirements concerning design and construction including requirements relating to construction materials, dike or berm design, liner material, liner thickness, procedures for installing liners, overflow warning devices, leak detection devices, monitor wells, and fences that the Director determines are necessary to prevent pollution.16 Tex. Admin. Code § 4.151
Adopted by Texas Register, Volume 50, Number 01, January 3, 2025, TexReg 0082, eff. 7/1/2025