(1) (a) All Class II facilities using landfilling methods shall compact and cover solid waste with a layer of at least 6 inches of approved earth cover material at the end of each operating day or at more frequent intervals if necessary to control disease vectors, fires, odors, blowing litter, and scavenging. Alternative daily cover materials such as geotextile fabrics, foams, compost, or other materials may be used in place of the 6 inches of approved earthen cover material only when approved by the department. The use of alternative daily cover materials must be done under a plan of operations approved of in advance by the department. The plan of operations for the use of alternative daily cover materials must include provisions for the application of 6 inches of approved earthen cover material at least once per week. The owner or operator must demonstrate to the department that the alternative material and thickness control disease vectors, fires, odors, blowing litter, and scavenging without presenting a threat to human health and the environment.   Any portion of a Class II landfill unit that will not receive additional waste within 90 days must have an intermediate cover of at least 1 foot of approved earthen materials. These steps must be taken unless the department is satisfied that the licensee has shown good cause for not covering.

(b) EPA's 1972 publication, "Sanitary Landfill Design and Operation", (#SW-65ts) shall be used as the general landfill design and operation manual for purposes of this rule.   The department may develop or adopt guidelines for other solid waste disposal methods and procedures.   Semi-solids should be mixed with other solid waste to prevent localized leaching; or separate, specialized disposal areas should be developed.

(c) Landfills must be fenced to prevent unauthorized access and must be supervised when open.

(d) Where transfer stations are utilized as part of a management system for Group II solid wastes, all containers must be maintained and kept in a sanitary manner and emptied at least once a week.

(e) Owners or operators of all Class II landfill units must implement a program at the facility for detecting and preventing the disposal of regulated hazardous wastes or polychlorinated biphenyls (PCB) wastes.   This program must include, at a minimum:

(i) random inspections of incoming loads unless the owner or operator takes other steps to ensure that incoming loads do not contain regulated hazardous wastes or PCB wastes;

(ii) records of any inspections;

(iii) training of facility personnel to recognize regulated hazardous waste and PCB wastes; and

(iv) notification of the department if a regulated hazardous waste or PCB waste is discovered at the facility.

(f) Owners or operators of all Class II landfill units must ensure that:

(i) the concentration of methane gas generated by the facility does not exceed 25% of the lower explosive limit for methane in facility structures (excluding gas control or recovery system components) ; and

(ii) the concentration of methane gas does not exceed the lower explosive limit for methane at the facility property boundary.

(g) Owners or operators of all Class II landfill units must implement a department approved routine methane monitoring program that ensures that the standards of (f) above are met and that meets the following requirements:

(i) The type and frequency of monitoring must be determined based on the following factors:

(A) soil conditions;

(B) the hydrogeologic conditions surrounding the facility;

(C) the hydraulic conditions surrounding the facility; and

(D) the location of facility structures and property boundaries.

(ii) The minimum frequency of monitoring must be quarterly.

(h) If methane gas levels exceeding the limits specified in (f) above are detected, the owner or operator must:

(i) immediately take all necessary steps to ensure protection of human health and notify the state director;

(ii) within 7 days of detection, place in the operating record and notify the department in writing of the methane gas levels detected and a description of the steps taken to protect human health; and

(iii) within 60 days of detection, implement a department approved remediation plan for the methane gas releases, place a copy of the plan in the operating record, and notify the department that the plan has been implemented.   The plan shall describe the nature and extent of the problem and the proposed remedy.

(i) Owners or operators of all solid waste management systems must ensure that the units do not violate any applicable requirements developed under a state implementation plan (SIP) approved or promulgated by the EPA administrator pursuant to section 110 of the Clean Air Act, as amended.

(j) Owners or operators of all Class II disposal units must design, construct, and maintain:

(i) a run-on control system to prevent flow onto the active portion of the landfill during the peak discharge from a 25-year storm;

(ii) a run-off control system from the active portion of the landfill to collect and control at least the water volume resulting from a 24-hour, 25-year storm.

(k) Run-off from the active portion of the disposal unit must be handled in accordance with (l) below.

(l) Class II disposal units may not:

(i) cause a discharge of pollutants into waters of the United States, including wetlands, that violates any requirements of the federal Clean Water Act, including, but not limited to, the national pollutant discharge elimination system (NPDES) requirements, pursuant to section 402 or the Montana pollutant discharge elimination system (MPDES) requirements found in ARM 17.30.1301, et seq.;

(ii) cause the discharge of a nonpoint source of pollution to waters of the United States, including wetlands, that violates any requirement of an area-wide or state-wide water quality management plan that has been approved under section 208 or 319 of the federal Clean Water Act, as amended.

(m) (i) Bulk or noncontainerized liquid waste may not be placed in Class II disposal units unless:

(A) approved of in advance by the department; and

(B) the waste is either:

(I) household waste other than septic waste; or

(II) leachate or gas condensate derived from the disposal unit and the disposal unit, whether it is a new or existing disposal or lateral expansion, and is designed with a composite liner and leachate collection system as described in ARM 17.50.506.

(ii) In order to obtain this exemption, the owner or operator must place a demonstration in the operating record showing that the conditions of (m) (i) (B) (II) above have been met and notify the department for prior approval.

(n) Containers holding liquid waste may not be placed in a Class II disposal unit unless:

(i) the container is a small container similar in size to that normally found in household waste;

(ii) the container is designed to hold liquids for use other than storage; or

(iii) the waste is household waste.

(o) Class II landfill facilities must weigh or otherwise accurately record all volumes of waste entering the facility.

(p) The owner or operator of a Class II disposal unit must record and retain at the facility or at an alternative location approved by the department, an operating record containing the following information as it becomes available:

(i) any location restriction demonstration required under this subchapter;

(ii) inspection records, training procedures, and notification procedures required under this subchapter;

(iii) gas monitoring results from monitoring and any remediation plans required by this subchapter;

(iv) any design documentation for construction or the placement of leachate or gas condensate in a landfill unit as required under this subchapter;

(v) any demonstration, certification, finding, monitoring, testing, or analytical data required by department ground water monitoring regulations found in ARM 17.50.701, et seq.;

(vi) closure and post-closure care plans and any monitoring, testing, or analytical data required by this subchapter;

(vii) any cost estimates and financial assurance documentation required by this subchapter;

(viii) any information demonstrating compliance with and approval of the small community exemption; and

(ix) any waste quantity records required under this subchapter.

(q) The owner/operator must notify the department when the documents from (p) above have been placed in or added to the operating record, and all information contained in the operating record must be furnished to the department and be made available at all reasonable times for inspection by the department and the public.

(i) Notification and department approval is required if the operating record is to be kept at a location other than the licensed facility.

(ii) The operating record is considered to be part of the solid waste management facility, regardless of its actual physical location, and must be made available at all reasonable times for inspection by the department and the public.

(2) Although Class III landfills are not required to cover wastes in disposal areas by earth materials daily, the wastes must be covered at least quarterly with 6 inches of a department approved earthen cover material.

(3) Class IV solid waste units and components thereof must be designed, constructed, maintained, and operated so as to control litter, insects, rodents, odor, aesthetics, residues, waste water, leachate, and air pollutants.

(a) Although daily cover is not required at Class IV units, an approved cover must be applied a minimum of every 3 months unless more frequent cover is needed to control litter.

(b) The plan of operations at Class IV landfill units must exclude Group II waste.   Conditionally exempt small quantity generator wastes must be removed to the greatest extent practicable.   Liquid paints, solvents, glues, resins, dyes, oils, pesticides, and other household hazardous waste must be removed from buildings prior to demolition.

(c) The following requirements also apply to Class IV units:

(i) fencing and staffing, (1) (c) of this rule;

(ii) waste screening, (1) (e) of this rule;

(iii) explosive gas control, (1) (f) of this rule;

(iv) air pollution, (1) (i) of this rule;

(v) surface water pollution, (1) (k) and (l) of this rule;

(vi) bulk liquids, (1) (m) and (n) of this rule, and;

(vii) record keeping, (1) (o) ,(p) and (q) of this rule.

(4) Resource recovery and solid waste treatment facilities and components thereof shall be designed, constructed, maintained, and operated so as to control litter, insects and rodents, odor, aesthetics, residues, waste water treatment, and air pollutants.

(5) Subsections (1) (e) and (g) of this rule are effective October 9, 1993, except that the application of those subsections to the existing landfill units and lateral expansions to existing units defined in ARM 17.50.501(4) is delayed until April 9, 1994.

(6) The department hereby adopts and incorporates by reference:

(a) the standards governing water pollution discharges contained in the federal Clean Water Act and ARM 17.30.1301, et seq.; and

(b) the standards governing nonpoint source pollutant discharges contained in Montana water quality management plans approved pursuant to sections 208 or 319 of the federal Clean Water Act.

(c) Copies of the federal Clean Water Act, water quality management plans, and ARM 17.30.1301, et seq., may be obtained from the Department of Environmental Quality, PO Box 200901, Helena, MT 59620-0901 [(406)444-1430].