(1) Design requirements.
    (a) Landfills that receive degradable wastes shall have a gas management system designed to prevent explosions and fires, and to minimize off-site odors, lateral migration of gases and damage to vegetation. Combustible gases shall be calibrated to methane. Owners or operators of such landfills shall submit a general gas management system design as part of their permit application, and may modify that design as necessary at the time of closure based upon site-specific conditions. Landfill gas management systems shall:
    1. Be designed to prevent the concentration of combustible gases generated by the landfill from:
    a. Exceeding twenty-five percent of the lower explosive limit for combustible gases in structures on- or off-site, excluding gas control or recovery components; and,
    b. Exceeding the lower explosive limit for combustible gases at or beyond the landfill property boundary,
    2. Be designed for site-specific conditions,
    3. Be designed to reduce gas pressure in the interior of the landfill by collecting the gases to prevent them from moving laterally. Air shall not be forced into the collection system. Passive venting or suction shall be used to extract gas; and,
    4. Be designed to not interfere with or cause failure of the liner, leachate control systems or final cover.
    (b) Flaring of landfill gases may be used as a method of gas control, particularly control of objectionable odors, in accordance with the permitting requirements of chapter 62-296, F.A.C.
    (c) Landfills using piping or a similar conduit to convey gas shall be furnished with a positive means of gas condensate collection and disposal at each low point in the conveyance system.
    (2) Monitoring requirements. Owners or operators of solid waste disposal units at landfills that have received degradable waste shall implement a routine gas monitoring program to ensure that the design requirements of subparagraphs (1)(a)1. and 3. of this rule are met. The routine gas monitoring program shall monitor concentrations of combustible gases at ambient monitoring points and in soil monitoring probes.
    (a) Ambient monitoring points. Ambient monitoring points shall be located in onsite structures, excluding gas control or recovery components, that can be impacted by combustible gases from the landfill as determined by the location of these structures and property boundaries of the facility.
    (b) Soil monitoring probes. Soil monitoring probes shall be installed along each property boundary segment of the facility, particularly those adjacent to off-site occupied structures within 100 feet of the property boundary or where distressed vegetation is present, and shall be spaced as needed to detect gas migration. When locating the soil monitoring probes, the owner or operator shall also consider the location of facility structures and the soil conditions, hydrogeologic conditions and hydraulic conditions surrounding the facility. Soil monitoring probes shall extend to the depth of the base of waste fill or at least three feet below ground surface, whichever is deeper. Sampling shall be conducted in the headspace of the monitoring probe without purging the gas before collecting the sample. Where sand, gravel, or more gas permeable soil strata may interconnect the waste deposit and the property boundary, multiple depth monitoring probes if a confining unit is not penetrated, or a single monitoring probe extending from the soil surface to the water table, are necessary to draw gas samples from the permeable layers.
    (c) All ambient monitoring points and soil monitoring probes shall be sampled quarterly for concentrations of combustible gases, and the results reported to the Department no later than 15 days after the end of the quarter in which the monitoring occurred. Combustible gases shall be determined as a percent of the lower explosive limit and shall be calibrated to methane.
    (3) Construction and control requirements. The gas management system shall be constructed and operated as authorized by a Department permit or this rule.
    (a) Gas remediation plan. If the results of monitoring show that combustible gas concentrations exceed the lower explosive limits specified in subsection (1) of this rule, the owner or operator shall:
    1. Immediately take all necessary steps to ensure protection of human health and notify the Department; and,
    2. Within seven days of detection, submit to the Department for approval a gas remediation plan for the gas releases. The plan shall describe the nature and extent of the problem and the proposed remedy. The remedy may include some or all of the gas management system design contained in subsection (1) of this rule. The remedy shall be completed within 60 days of detection unless otherwise approved by the Department.
    (b) Odor remediation plan. The facility shall be operated to control objectionable odors in accordance with subsection 62-296.320(2), F.A.C. After being notified by the Department that objectionable odors have been confirmed beyond the landfill property boundary, the owner or operator shall:
    1. Immediately take steps to reduce the objectionable odors. Such steps may include applying or increasing initial cover, reducing the size of the working face, and ceasing operations in the areas where odors have been detected,
    2. Submit to the Department for approval an odor remediation plan for the gas releases. The plan shall describe the nature and extent of the problem and the proposed long-term remedy. The remedy shall be initiated within 30 days of approval.
    3. Implement a routine odor monitoring program to determine the timing and extent of any off-site odors, and to evaluate the effectiveness of the odor remediation plan.
    (4) Closure requirements. Owners or operators of solid waste disposal units at landfills that have received degradable waste and have been filled to their design dimensions, and have not been certified closed prior to May 27, 2001, shall construct, if not already constructed, and operate a gas management system to ensure that the requirements of subsections (1), (2) and (3) of this rule, are met.
    (5) Landfill gas recovery facilities.
    (a) Landfill gas recovery facilities are considered solid waste management facilities, and shall be constructed and operated only in accordance with a Department permit. If a gas recovery facility is included in the approved closure plan or closure permit of the landfill, no separate permit for the facility is required, provided that the facility must meet all the requirements of this subsection.
    (b) The application shall be submitted on Form 62-701.900(1), and shall contain at least the following:
    1. The information contained in subsections 62-701.320(7) and 62-701.330(3), F.A.C.,
    2. Where relevant and practical, the information required in subsection 62-701.600(4), F.A.C.,
    3. An estimate of the quantities of gas condensate currently collected or expected to be collected, and a description of how the condensate is or will be disposed of,
    4. A description of the procedures for sampling, analyzing, and reporting data from the condensate sampling; and,
    5. A closure plan that shall include methods to control landfill gasses after operation of the recovery facility ceases and any other requirements contained in subsection 62-701.400(10), F.A.C.
    (6) Compliance with this section does not relieve an applicant from compliance with any applicable air requirements of Title V, county ordinance, or local programs.
Rulemaking Authority 403.061, 403.704 FS. Law Implemented 403.702, 403.704, 403.707 FS. History-New 5-27-01, Amended 1-6-10, 8-12-12.