Effective date: 2/15/2015
(1) Applicability. Construction of a solid waste disposal unit on top of or against the side slopes of a previously filled landfill, whether active, closed, or inactive is considered vertical expansion of that landfill. Vertical expansion shall require either a modification of the landfill permit, or a new permit if the landfill has been closed. If a landfill has not been closed at the time of the vertical expansion, then the closure requirements of that landfill will apply at the time of closure of the vertical expansion, unless the closure requirements for the vertical expansion are more stringent. The following requirements shall apply:
Terms Used In Florida Regulations 62-701.430
- Closure: means the cessation of operation of a solid waste management facility and the act of securing such a facility so that it will pose no significant threat to human health or the environment. See Florida Regulations 62-701.200
- Construction and demolition debris: means discarded materials generally considered to be not water soluble and non-hazardous in nature, including but not limited to steel, glass, brick, concrete, asphalt material, pipe, gypsum wallboard, and lumber, from the construction or destruction of a structure as part of a construction or demolition project or from the renovation of a structure, including such debris from construction of structures at a site remote from the construction or demolition project site. See Florida Regulations 62-701.200
- Disposal: means the discharge, deposit, injection, dumping, spilling, leaking, or placing of any solid waste into or upon any land or water so that such solid waste or any constituent thereof may enter other lands or be emitted into the air or discharged into any waters, including ground waters, or otherwise enter the environment. See Florida Regulations 62-701.200
- Geomembrane: means a low-permeability synthetic membrane used as an integral part of a system designed to limit the movement of liquid or gas in the system. See Florida Regulations 62-701.200
- HDPE: means high density polyethylene. See Florida Regulations 62-701.200
- Land clearing debris: means rocks, soils, tree remains, trees, and other vegetative matter that normally results from land clearing or land development operations for a construction project. See Florida Regulations 62-701.200
- Landfill: means a solid waste disposal facility, which is an area of land or an excavation where wastes are or have been placed for disposal, for which a permit, other than a general permit, is required by section 403. See Florida Regulations 62-701.200
- Leachate: means liquid that has passed through or emerged from solid waste and may contain soluble, suspended or miscible materials. See Florida Regulations 62-701.200
- Liner: means a continuous layer of low-permeability natural or synthetic materials, under the bottom and sides of a landfill, solid waste disposal unit, or leachate surface impoundment, which controls the downward or lateral escape of waste constituents, or leachate. See Florida Regulations 62-701.200
- Liner system: means a system of leachate collection and liner layers comprised of natural or synthetic materials installed between the subgrade and the waste for the purpose of containing the waste and collecting and removing leachate. See Florida Regulations 62-701.200
- Objectionable odors: has the meaning given that term in rule 62-210. See Florida Regulations 62-701.200
- Recycling: means any process by which solid waste, or materials which would otherwise become solid waste, are collected, separated, or processed and reused or returned to use in the form of raw materials or products. See Florida Regulations 62-701.200
- Settlement: Parties to a lawsuit resolve their difference without having a trial. Settlements often involve the payment of compensation by one party in satisfaction of the other party's claims.
- Solid waste: means : sludge that is not regulated under the federal Clean Water Act or Clean Air Act, as well as sludge from a waste treatment works, water supply treatment plant, or air pollution control facility; or garbage, rubbish, refuse, special waste, or other discarded material, including solid, liquid, semi-solid, or contained gaseous material resulting from domestic, industrial, commercial, mining, agricultural, or governmental operations. See Florida Regulations 62-701.200
(b) For vertical expansion over lined landfills, no interface liner is required between the old and new landfill slopes.
(c) For vertical expansion over landfills that were not constructed with a liner system or were not constructed in accordance with permit requirements, the vertical expansion shall comply with all the requirements of rule 62-701.400, F.A.C., with the following exceptions:
1. Side slopes of six feet horizontal to one foot vertical rise or steeper require the installation of a single geomembrane slope liner overlain by a leachate collection and removal system.
2. The slope liner shall consist of a 60-mil or thicker HDPE geomembrane.
3. The liner shall be protected from physical damage by a 24-inch thick protective layer above the liner and a bedding layer below the liner at least 24 inches thick to protect against the calculated differential settlement.
4. In all vertical expansion construction, grades shall slope toward the new expansion area.
5. If the vertical expansion consists exclusively of construction and demolition debris, the expansion must comply with the requirements of rule 62-701.730, F.A.C., as well as paragraph (a) of this subsection. If the vertical expansion consists exclusively of land clearing debris, the expansion must comply with the requirements of rule 62-701.803, F.A.C., as well as paragraph (a) of this subsection.
6. If the vertical expansion consists of a composting operation, it must meet the requirements of chapter 62-709, F.A.C., as well as paragraph (a), of this subsection.
7. If the vertical expansion consists of a Class III landfill, the provisions of paragraph 62-701.340(3)(c), F.A.C., apply.
(d) The provisions of subsection 62-701.610(1), F.A.C., are applicable to all operations, including recycling operations, conducted on top of closed landfills.
(2) Construction requirements. The design for the vertical expansion shall also provide calculations and supporting information on the following factors:
(a) Construction on the slopes of a filled landfill requires a determination of foundation stability in accordance with rule 62-701.410, F.A.C., and calculations for the total settlement of the waste in the existing landfill and the waste that will be disposed of in the new disposal area to be constructed. Total settlement calculations shall address both compression and differential settlement and shall be based on worst case predictions. Total settlement calculations shall show the final elevations of the liner systems, that gravity drainage will be maintained, and that no other component of the design will be adversely affected.
(b) The vertical expansion design shall achieve a minimum factor of safety 1.5 using peak strengths for:
1. The liner system stability for liner systems installed over existing landfill slopes to prevent sliding along the interface between liner system components; and,
2. Deep stability, to prevent sliding along all potential failure surfaces through the waste mass, along the liner systems, and through the foundation soils.
(c) Surface water management during construction of the vertical expansion over the slopes of an existing landfill shall be consistent with subsection 62-701.400(9), F.A.C., and shall require proper design of the drainageway at the interface between the existing slopes and vertical expansion area. The design shall;
1. Prevent infiltration into the existing and new landfills,
2. Minimize erosion of cover materials,
3. Carry the calculated flow; and,
4. Comply with the cover requirements.
(d) A gas control system shall be installed to vent gas from the interface between the existing landfill slopes and the vertical expansion slopes to prevent accumulation of gas under the new liner system. Gas-venting shall include a gas-venting layer or system of gas collection wells under the entire slope that will be covered by the new liner system.
Rulemaking Authority 403.061, 403.704 FS. Implements Florida Statutes § 403.702, 403.704, 403.707. History—New 1-6-93, Amended 5-19-94, Formerly 17-701.430, Amended 5-27-01, 1-6-10, 2-15-15.