SECTION 334.502. Design and Operating Requirements of Stockpiles and Land Surface Treatment Units

(a) A stockpile or land surface treatment unit located at any storage or treatment facility or at any leaking petroleum storage tank site shall have an appropriate means of preventing any discharge or release of petroleum-substance waste or petroleum-substance waste constituents into any media. This shall be accomplished with:

(1) a synthetic, impermeable liner that is designed, constructed, and installed to prevent any migration of petroleum-substance wastes out of the stockpile or land surface treatment unit into the adjacent subsurface soil, groundwater, or surface water at any time during the active life (including the closure period) of the stockpile, or land surface treatment unit. The liner shall be constructed of materials that do not allow petroleum-substance waste or petroleum-substance waste constituents to migrate into the liner itself or into the adjacent subsurface soil, groundwater, or surface water during the active life of the facility. The liner shall:

(A) be constructed of materials that have appropriate chemical properties and sufficient strength and thickness to prevent failure due to pressure gradients (including static head and external hydro geologic forces), physical contact with the hydrocarbons or leachate to which they are exposed, climatic conditions, the stress of installation, and the stress of daily operations;

(B) be placed upon a foundation or base capable of providing support to the liner and resistance to pressure gradients above and below the liner to prevent failure of the liner due to settlement, compression, tearing, or uplift;

(C) be installed to cover all surrounding earth likely to be in contact with the petroleum-substance waste or leachate; and

(D) contain a leachate collection and removal system immediately above the liner that is designed, constructed, maintained, and operated to collect and remove leachate and rainwater from the stockpile or land surface treatment unit. The facility owner and operator shall specify the design and operating conditions which will ensure that the leachate depth over the liner does not exceed the depth of soil on the liner. The leachate collection and removal system shall be constructed of materials that are:

(i) chemically resistant to the hydrocarbons managed in the pile and the leachate expected to be generated; and

(ii) of sufficient strength and thickness to prevent collapse under the pressures exerted by overlaying petroleum-substance wastes, petroleum-substance waste cover materials, and any equipment used at the stockpile or treatment unit; and

(iii) designed and operated to function without clogging through the scheduled life of the stockpile or land surface treatment unit; or

(2) an alternate design or operating practice that is effective in preventing any release or discharge and is approved by the agency. The facility owner or operator shall demonstrate that the alternate design or operating practices, together with location characteristics, will prevent the migration of any petroleum- substance waste constituents into the soil, groundwater, or surface water at any future time. In deciding whether to approve the alternate design, the agency will consider:

(A) the nature and quantity of the wastes;

(B) the proposed alternate design and operation;

(C) the hydro geologic setting of the facility, including a tentative capacity and thickness of the liners and soils present between the stockpile or land surface treatment unit and groundwater or surface water; and

(D) all other factors which would influence the quality and mobility of the leachate produced and the potential for it to migrate to soil, groundwater, or surface water.

(b) The facility owner or operator shall design, construct, operate, and maintain a run-on control system capable of preventing flow onto the active portion of the stockpile or land surface treatment unit.

(c) The facility owner or operator shall design, construct, operate, and maintain a run-off management system to prevent flow from a stockpile or land surface treatment unit.

(d) Collection and holding facilities (e.g., tanks or basins) associated with run-on and run-off control systems shall be emptied and managed expeditiously in accordance with applicable state and federal requirements after storms to maintain design capacity of the system.

(e) If the stockpile or land surface treatment unit contains any particulate matter which may be subject to wind dispersal, the facility owner or operator shall cover or otherwise manage the stockpile or land surface treatment unit to control wind dispersal.

(f) The agency may specify other design and operating practices that may be necessary to ensure that the requirements of this section are satisfied.

(g) The facility owner or operator shall ensure that treatment is initiated on stockpiled soil within 90 days from the date of receipt at the facility and that the treated soil is removed from the facility for final disposition within 90 days after completing treatment.

(h) In addition to the requirements specified in subsections (a) - (g) of this section, the facility owner or operator shall design, construct, operate, and maintain the land surface treatment unit to maximize the degradation, transformation, or immobilization of petroleum-substance waste constituents in the treatment area. At a minimum, the facility owner or operator shall specify the following items, if applicable, in the facility registration application:

(1) the rate and method of petroleum-substance waste application to the treatment area;

(2) measures to control soil pH;

(3) measures to enhance microbial or chemical reactions (e.g., fertilization); and

(4) measures to control the moisture content of the treatment area.

(i) The facility owner or operator shall inspect the unit weekly and after storms to detect evidence of:

(1) deterioration, malfunctions, or improper operation of run-on and run-off control systems; and

(2) improper functioning of wind dispersal control measures.

Source Note: The provisions of this §334.502 adopted to be effective December 27, 1996, 21 TexReg 12177; amended to be effective November 23, 2000, 25 TexReg 11442