OAR 340-230-0365: Municipal Waste Combustors: Small Municipal Waste Combustion Unit

(1) Applicability: (a) OAR 340-230-0365 through 340-230-0395 apply to each municipal waste combustion unit that has the capacity to combust at least 35 tons per day of municipal solid waste but no more than 250 tons per day of municipal solid waste or refuse-derived fuel on which construction commenced on or before August 30, 1999. (A) Class I units are small municipal waste combustion units that are located at municipal waste combustion plants with an aggregate plant combustion capacity greater than 250 tons per day of municipal solid waste. (B) Class II units are small municipal waste combustion units that are located at municipal waste combustion plants with an aggregate plant combustion capacity less than or equal to 250 tons per day of municipal solid waste. (b) MWC subject to OAR 340-230-0365 through 340-230-0395 are not subject to the incinerator rules in 340-230-0100 through 340-230-0150. (2) The following units in OAR 340-230-0365(2)(a)–(k) are exempt from the requirements in 340-230-0370 through 340-230-0395: (a) Small municipal waste combustion units that combust less than 11 tons per day are exempt if the following requirements are met (A) The municipal waste combustion unit is subject to a federally enforceable permit limiting the amount of municipal solid waste combusted to less than 11 tons per day. (B) The owner or operator of the unit notifies the Department of an exemption claim. (C) The owner or operator of the unit provides a copy of the federally enforceable permit. (D) The owner or operator of the unit keeps daily records of the amount of municipal solid waste combusted. (b) Small power production units are exempt if four requirements are met: (A) The unit qualifies as a small power production facility under section 3(17)(C) of the Federal Power Act (16 U.S.C. § 796(17)(C)). (B) The unit combusts homogeneous waste (excluding refuse-derived fuel) to produce electricity. (C) The owner or operator of the unit notifies the Department of an exemption claim. (D) The owner or operator of the unit provides documentation that the unit qualifies for the exemption. (c) Cogeneration units are exempt if four requirements are met: (A) The unit qualifies as a cogeneration facility under section 3(18)(B) of the Federal Power Act (16 U.S.C. § 796(18)(B)). (B) The unit combusts homogeneous waste (excluding refuse-derived fuel) to produce electricity and steam or other forms of energy used for industrial, commercial, heating, or cooling purposes. (C) The owner or operator of the unit notifies the Department of an exemption claim. (D) The owner or operator of the unit provides documentation that the unit qualifies for the exemption. (d) Municipal waste combustion units that combust only tires are exempt if three requirements are met: (A) The municipal waste combustion unit combusts a single-item waste stream of tires and no other municipal waste (the unit can co- fire coal, fuel oil, natural gas, or other non municipal solid waste). (B) The owner or operator of the unit notifies the Department of an exemption claim. (C) The owner or operator of the unit provides documentation that the unit qualifies for the exemption. (e) Hazardous waste combustion units are exempt if the units have received a permit under section 3005 of the Solid Waste Disposal Act (42 U.S.C. § 6925). (f) Materials recovery units are exempt if the units combust waste mainly to recover metals. Primary and secondary smelters may qualify for the exemption. (g) Co-fired units are exempt if four requirements are met: (A) The unit has a federally enforceable permit limiting municipal solid waste combustion to 30 percent of the total fuel input by weight. (B) The owner or operator of the unit notifies the Department of an exemption claim. (C) The owner or operator of the unit provides documentation that the unit qualifies for the exemption. (D) The owner or operator records the weights, each quarter, of municipal solid waste and of all other fuels combusted. (h) Plastics/rubber recycling units are exempt if four requirements are met: (B) The pyrolysis/combustion unit is an integrated part of a plastics/rubber recycling unit. (C) The owner or operator of the unit records the weight, each quarter, of plastics, rubber, and rubber tires processed. (D) The owner or operator of the unit records the weight, each quarter, of feedstocks produced and marketed from chemical plants and petroleum refineries. (E) The owner or operator of the unit keeps the name and address of the purchaser of the feedstocks. (i) Units that combust fuels made from products of plastics/rubber recycling plants are exempt if two requirements are met: (A) The unit combusts gasoline, diesel fuel, jet fuel, fuel oils, residual oil, refinery gas, petroleum coke, liquefied petroleum gas, propane, or butane produced by chemical plants or petroleum refineries that use feed stocks produced by plastics/rubber recycling units. (B) The unit does not combust any other municipal solid waste. (j) Cement kilns that combust municipal solid waste are exempt. (3) Reducing small municipal waste combustion unit capacity. An owner or operator of an affected municipal waste combustion unit may choose to reduce, by the final compliance date, the maximum combustion capacity of the unit to less than 35 tons per day of municipal solid waste. A final control plan must be submitted with the notifications of achievement of increments of progress as specified in OAR 340-230-0370(1)(a). The final control plan must include a description of the physical changes that will be made to accomplish the reduction and calculations of the current maximum combustion capacity and the planned maximum combustion capacity after the reduction, using the equations specified below. A permit restriction or a change in the method of operation does not qualify as a reduction in capacity. (a) For a municipal waste combustion unit that can operate continuously for 24-hour periods, calculate the municipal waste combustion unit capacity based on 24 hours of operation at the maximum charge rate. To determine the maximum charge rate, use one of two methods. (i) If the municipal waste combustion unit combusts refuse-derived fuel, use a heating value of 12,800 kilojoules per kilogram (5,500 British thermal units per pound). (ii) If the municipal waste combustion unit combusts municipal solid waste, use a heating value of 10,500 kilojoules per kilogram (4,500 British thermal units per pound). (b) For municipal waste combustion units with a design not based on heat input capacity, use the maximum designed charging rate. (c) For a batch municipal waste combustion unit calculate the capacity of a batch municipal waste combustion unit as the maximum design amount of municipal solid waste charged per batch multiplied by the maximum number of batches processed in 24 hours. Calculate the maximum number of batches by dividing 24 by the number of hours needed to process one batch. Retain fractional batches in the calculation. For example, if one batch requires 16 hours, the municipal waste combustion unit can combust 24/16, or 1.5 batches, in 24 hours.