Current through Register Vol. 51, No. 22, November 1, 2024
Section 26.13.05.12 - Waste PilesA. Applicability. (1) This regulation applies to owners and operators of facilities that store or treat hazardous waste in piles, except as Regulation .01 of this chapter provides otherwise.(2) The owner or operator of any waste pile that is inside or under a structure that provides protection from precipitation so that neither run-off nor leachate is generated is not subject to regulation under §§B and D of this regulation and Regulations .06-.06-7 of this chapter, if:(a) Liquids or materials containing free liquids are not placed in the pile;(b) The pile is protected from surface water run-on by the structure or in some other manner;(c) The pile is designed and operated to control dispersal of the waste by wind, when necessary, by means other than wetting; and(d) The pile does not generate leachate through decomposition or other reactions.B. Design and Operating Requirements.(1) A waste pile except for an existing portion of a waste pile, shall have: (a) A liner that is designed, constructed, and installed to prevent any migration of wastes out of the pile into the adjacent subsurface soil or ground water or surface water at any time during the active life (including the closure period) of the waste pile. The liner may be constructed of materials that may allow waste to migrate into the liner itself (but not into the adjacent subsurface soil or ground water or surface water) during the active life of the facility. The liner shall be: (i) 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 hydrogeologic forces), physical contact with the waste or leachate to which they are exposed, climatic conditions, the stress of installation, and the stress of daily operation;(ii) 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, or uplift; and(iii) Installed to cover all surrounding earth likely to be in contact with the waste or leachate.(b) A leachate collection and removal system immediately above the liner that is designed, constructed, maintained, and operated to collect and remove leachate from the pile. The Secretary will specify design and operating conditions in the permit to ensure that the leachate depth over the liner does not exceed 30 cm (1 foot). The leachate collection and removal system shall be:(i) Constructed of materials that are chemically resistant to the waste managed in the pile and the leachate expected to be generated, and of sufficient strength and thickness to prevent collapse under pressures exerted by overlaying wastes, waste cover materials, and by any equipment used at the pile; and(ii) Designed and operated to function without clogging through the scheduled closure of the waste pile.(c) A containment system which complies with §D of this regulation.(2) The owner or operator will be exempted from the requirements of §B(1) if the Secretary finds, based on a demonstration by the owner or operator, that alternate design and operating practices together with location characteristics, will prevent the migration of any hazardous constituents (see Regulation .06-1B of this chapter) into the ground water or surface water at any future time. In deciding whether to grant an exemption, the Secretary shall consider: (a) The nature and quantity of the wastes;(b) The proposed alternate design and operation;(c) The hydrogeologic setting of the facility, including attenuative capacity and thickness of the liners and soils present between the pile and ground water 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 ground water or surface water.(3) The owner or operator shall: (a) Install two or more liners and a leachate collection and removal system above and between these liners for each: (ii) Lateral expansion of a waste pile unit; and(iii) Replacement of an existing waste pile unit; and(b) Ensure that the liners and leachate collection and removal system meet the requirements of §D of this regulation.(4) The owner or operator shall design, construct, operate, and maintain a run-on control system capable of preventing flow onto the active portion of the pile during peak discharge from at least a 25-year storm.(5) The owner or operator shall design, construct, operate, and maintain a run-off management system to collect and control at least the water volume resulting from a 24-hour, 25-year storm.(6) Collection and holding facilities (for example, tanks or basins) associated with run-on and run-off control systems shall be emptied or otherwise managed expeditiously after storms to maintain design capacity of the system.(7) If the pile contains any particulate matter which may be subject to wind dispersal, the owner or operator shall cover or otherwise manage the pile to control wind dispersal.(8) The Secretary shall specify in the permit all design and operating practices that are necessary to ensure that the requirements of this section are satisfied.C. Waste Analysis. In addition to the waste analysis required by Regulation .02D, of this chapter, the owner or operator shall analyze a representative sample of waste from each incoming movement before adding the waste to any existing pile, unless the only wastes the facility receives which are amenable to piling are compatible with each other, or the waste received is compatible with the waste in the pile to which it is to be added. This analysis conducted shall be capable of differentiating between the types of hazardous waste the owner or operator places in piles, so that mixing of incompatible waste does not inadvertently occur. The analysis shall include a visual comparison of color and texture.D. Containment Systems. (1) Except as provided in §D(2) and (3) of this regulation, the owner or operator shall ensure that a waste pile subject to this regulation includes a containment system that: (a) Incorporates two or more liners and a leachate collection and removal system above and between the liners, with the leachate collection and removal system also serving as a leak detection system; and(b) Is designed, constructed, and operated in accordance with the requirements of 40 CFR § 264.251(c)(1)-(5), except that, in meeting these requirements, the owner or operator shall substitute "Secretary" for "Regional Administrator".(2) The Secretary may approve alternative designs and operating practices to those specified in §D(1) of this regulation if the owner or operator demonstrates to the Secretary that the proposed designs and operating practices, together with location characteristics, will: (a) Prevent the migration of any hazardous constituent into the ground water or surface water at least as effectively as the liners and leachate collection and removal systems specified in §D(1) of this regulation; and(b) Allow detection of leaks of hazardous constituents through the top liner at least as effectively as the design and operating practices specified in §D(1) of this regulation.(3) The requirements of §D(1)(a) of this regulation do not apply to a monofil that has been granted a waiver by the Secretary in accordance with Regulation .11D(6) of this chapter.D-1. Action Leakage Rate. (1) This section establishes requirements concerning the maximum design flow rate that the leak detection system required by §D(1)(a) of this regulation can remove without the fluid head on the bottom liner exceeding 1 foot.(2) For the purposes of this section, "action leakage rate" means the maximum design flow rate described in §D-1(1) of this regulation.(3) The owner or operator shall provide the Department with the information that the Department considers necessary for the specification of a valid action leakage rate that incorporates an adequate margin of safety to allow for uncertainties, as specified in §D-1(4) of this regulation.(4) For a waste pile subject to §D(1) of this regulation, the Department shall specify an action leakage rate that: (a) Includes an adequate safety margin, considering:(i) Uncertainties in the design, construction, operation, and location of the leak detection system;(ii) The characteristics of the waste and leachate;(iii) The likelihood that other sources may contribute to liquids in the leak detection system, and the amounts of these liquids; and(iv) Proposed response actions; and(b) If exceeded, obligates the owner or operator to respond as specified in §D-2 of this regulation.(5) To determine if the action leakage rate has been exceeded, the owner or operator shall:(a) Convert the weekly flow rate from the monitoring data obtained in accordance with §E(3) of this regulation to an average daily flow rate in gallons per acre per day for each sump; and(b) Unless the Department approves a different calculation, calculate the average daily flow rate for each sump on a weekly basis during the active life and closure period for the unit.D-2. Response Action Plan.(1) Before managing hazardous waste in a waste pile that is subject to §D(1) or (2) of this regulation, the owner or operator shall:(a) Develop a response action plan that meets the requirements of §D-2(2) of this regulation; and(b) Obtain the approval of the Department for the response action plan.(2) The owner or operator shall ensure that the response action plan:(a) At a minimum describes the actions specified in 40 CFR § 264.253(b), except that, in complying with 40 CFR § 264.253(b), the owner or operator shall substitute "Department" for "Regional Administrator"; and(b) Incorporates the procedures specified in 40 CFR § 264.253(c).(3) If the action leakage rate specified under §D-2 of this regulation is exceeded, then the owner or operator shall respond as specified in the approved response action plan.E. Inspections and Testing. (1) Except in the case of an existing portion of a waste pile exempt from the requirements of §B(1) of this regulation, the owner or operator shall, during construction and immediately after installation, inspect:(a) Liner systems and covers for uniformity, damage, and imperfections such as holes, cracks, thin spots, and foreign materials;(b) Manufactured liner materials and covers, such as membranes, sheets, and coatings, to ensure tight seams and joints and the absence of tears or blisters; and(c) Soil-based and admixed liners and covers for imperfections including lenses, cracks, channels, root holes, or other structural non-uniformities that may cause an increase in the permeability of the liner or cover.(2) While a waste pile is in operation, the owner or operator shall inspect the pile weekly and after storms to detect evidence of any of the following: (a) Deterioration, malfunctions, or improper operation of run-on and run-off control systems;(b) The presence of liquids in leak detection systems, if installed;(c) Proper functioning of wind dispersal control systems, if present; and(d) The presence of leachate in and proper functioning of leachate collection and removal systems, if present.(3) For a waste pile required to have a leak detection system under §D(1) of this regulation, the owner or operator shall record the amount of liquid removed from each leak detection sump at least once each week during the active life and closure period of the waste pile.F. Containment System Repairs, Contingency Plans. (1) Whenever there is an indication of a possible failure of the containment system, the system shall be inspected in accordance with the provisions of the containment system evaluation and repair plan required by §F(4) of this regulation. Indications of possible failure of the containment system include liquid detected in the leachate detection system (when applicable), evidence of leakage or the potential for leakage in the base, erosion of the base, or apparent or potential deterioration of the liner and liners based on observation or test samples of the liner materials.(2) Whenever there is a positive indication of a failure of the containment system, the waste pile shall be removed from service. Indications of positive failure of containment system include waste detected in the leachate detection system (when applicable), or a breach (for example, a hole, tear, crack, or separation) in the base.(3) If the waste pile must be removed from service as required by §F(2), of this regulation, the owner or operator shall:(a) Immediately stop adding wastes to the pile;(b) Immediately contain any leakage which has or is occurring;(c) Immediately cause the leak to be stopped; and(d) If the leak cannot be stopped by another means, remove the waste from the base.(4) As a part of the contingency plan required in Regulation .04, of this chapter, the owner or operator shall specify: (a) A procedure for complying with the requirements of §F(3) of this regulation; and(b) A containment system evaluation and repair plan describing:(i) Testing and monitoring techniques;(ii) Procedures to be followed to evaluate the integrity of the containment system in the event of a possible failure;(iii) A schedule of actions to be taken in the event of a possible failure; and(iv) A description of the repair techniques to be used in the event of leakage due to containment system failure or deterioration which does not require the waste pile to be removed from service.(5) A waste pile that has been removed from service in accordance with §F(2), of this regulation, may not be restored to service unless the containment system has been:(b) Certified by a qualified engineer as meeting the design specifications approved in the permit.(6) A waste pile that has been removed from service in accordance with §F(2), of this regulation, and that is not being repaired shall be closed in accordance with §I, of this regulation.G. Special Requirements for Ignitable or Reactive Waste. A person may not place ignitable or reactive waste in a pile unless the waste and waste pile satisfy all applicable requirements of 40 CFR Part 268, and: (1) The waste is treated, rendered, or mixed before or immediately after placement in the pile so that: (a) The resulting waste, mixture, or dissolution of materials no longer meets the definition of ignitable or reactive waste under COMAR 26.13.02.11 and .13, and(b) Regulation .02H of this chapter is complied with; or(2) The waste is managed in such a way that it is protected from any material or conditions which may cause it to ignite or react.H. Special Requirements for Incompatible Wastes.(1) Incompatible wastes, or incompatible wastes and materials, (see Regulation .24, of this chapter, for examples) may not be placed in the same pile, unless Regulation .02H(2) is complied with.(2) A pile of hazardous waste that is incompatible with any waste or other material stored nearby in other containers, piles, open tanks, or surface impoundments shall be separated from the other materials, or protected from them by means of a dike, berm, wall, or other device.(3) Hazardous waste may not be piled on the same area where incompatible wastes or materials were previously piled, unless the area has been decontaminated sufficiently to ensure compliance with Regulation .02H(2) of this chapter.I. Closure and Post-Closure Care. (1) At closure, the owner or operator shall remove or decontaminate all waste residues, contaminated containment system components (liners, etc.), contaminated subsoils, and structures and equipment contaminated with waste and leachate, and manage them as hazardous waste unless COMAR 26.13.02.03D applies.(2) If, after removing or decontaminating all residues and making all reasonable efforts to effect removal or decontamination of contaminated components, subsoils, structures, and equipment as required in §I(1), of this regulation, the owner or operator finds that not all contaminated subsoils can be practicably removed or decontaminated, he shall close the facility and perform post-closure care in accordance with the closure and post-closure care requirements that apply to landfills.(3) The owner or operator of a waste pile that does not comply with the liner requirements of §B(1)(a), of this regulation, and is not exempt from them in accordance with §A(2) or B(2), of this regulation, shall: (a) Include in the closure plan for the pile under Regulation .07C, of this chapter, both a plan for complying with §I(1), of this regulation, and a contingency plan for complying with §I(2), of this regulation, if not all contaminated subsoils can be practicably removed at closure; and(b) Prepare a contingency post-closure plan under Regulation .07H, of this chapter, for complying with §I(2), of this regulation, if not all contaminated subsoils can be practicably removed at closure.(4) The cost estimates calculated under Regulation .08 for closure and post-closure care of a pile subject to §I(3), of this regulation, shall include the cost of complying with the contingent closure plan and the contingency post-closure plan, but are not required to include the cost of expected closure under §I(1), of this regulation.J. Special Requirements for Hazardous Wastes F020, F021, F022, F023, F026, and F027. (1) Hazardous Waste F020, F021, F022, F023, F026, and F027 may not be placed in waste piles that are not enclosed as defined in §A(2), of this regulation, unless the owner or operator operates the waste pile in accordance with a management plan for these wastes that is approved by the Secretary under the standards set out in this section, and in accord with all other applicable requirements of this chapter. The factors to be considered are: (a) The volume, physical, and chemical characteristics of the wastes, including their potential to migrate through soil or to volatilize or escape into the atmosphere;(b) The attenuative properties of underlying and surrounding soils or other materials;(c) The mobilizing properties of other materials co-disposed with these wastes; and(d) The effectiveness of additional treatment, design, or monitoring techniques.(2) The Secretary may determine that additional design, operating, and monitoring requirements are necessary for piles managing hazardous wastes F020, F021, F022, F023, F026, and F027 in order to reduce the possibility of migration of these wastes to ground water, surface water, or air so as to protect human health and the environment.Md. Code Regs. 26.13.05.12
Regulations .12 adopted as an emergency provision effective November 18, 1980 (7:25 Md. R. S-1); adopted permanently effective April 3, 1981 (8:7 Md. R. 642)
Regulations .12A, B, D, D-1, E, G, amended, effective February 13, 1984 (11:3 Md. R. 202)
Regulations .12D-1 amended, effective July 30, 1984 (11:15 Md. R. 1330)
Regulation .12B, D-1 amended effective April 18, 1988 (15:8 Md. R. 1009)
Regulations .12 amended effective January 31, 1983 (10:2 Md. R. 110)
Regulations .12D-1 amended, effective July 30, 1984 (11:15 Md. R. 1330)
Regulation .12H adopted effective April 18, 1988 (15:8 Md. R. 1009); amended effective 49:1 Md. R. 14, eff. 1/13/2022