Outdated Standard Exemptions 90-97, April 25, 1986

Exemptions

Clicking on a highlighted number below links you to the standard exemption.

90. Pathological incinerators with a manufacturer's rated capacity for pathological waste equal to or less than 200 pounds per hour provided that the following conditions are satisfied:

(a) The incinerator is a dual chamber design.
(b) Burners shall be located in each chamber, sized to manufacturer's specifications and automatically operated when the unit is charged with waste.
(c) Operating instructions are posted at the unit.
(d) The incinerator shall operate with no visible emissions except for uncombined water.
(e) Fuel shall be sweet natural gas, liquid petroleum gas or No. 2 fuel oil with less than 0.5% sulfur by weight or electric power.
(f) There shall be no obstruction to stack flow, such as by rain caps, unless such devices are designed to automatically open when the incinerator is operated. Items such as properly installed and maintained spark arrestors are not considered obstructions.
(g) This facility shall be used solely for the disposal of waste materials. Incinerators used in the processing or recovery of materials or in the commercial disposal of wastes are not covered by this exemption. Heat recovery, where no auxiliary fuel is burned, is allowed by this exemption.
(h) Before construction operation begins, the facility shall be registered with the appropriate Regional Office using Form PI-7.
(i) For crematories, the manufacturer's rated capacity shall be equal to or less than 200 lb/hr averaged over the number of hours in a normal batch burn cycle.

91. All bulk mineral product (except asbestos) handling facilities that operate according to the following conditions:

(a) All material is transported in a closed conveying system and all exhaust air to the atmosphere is vented through a fabric filter having a maximum filtering velocity of 4 ft/min with mechanical cleaning or 7 ft/min with air cleaning.
(b) All permanent in-plant roads and vehicle work areas shall be watered, treated with dust suppressant chemicals, oiled or paved and cleaned as necessary to achieve maximum control of dust emissions.
(c) Before construction begins, written site approval must be received from the Executive Director of the Texas Air Control Board and the facility shall be registered with the appropriate Regional Office using Form PI-7.

92. All oil well servicing bulk sand handling facilities that operate according to the following conditions:

(a) All sand shall be prewashed.
(b) All handling of sand is mechanical or if sand is conveyed pneumatically, the conveying air shall be vented to the atmosphere through a fabric filter(s) having a maximum filtering velocity of 4.0 ft/min with mechanical cleaning or 7 ft/min with air cleaning.
(c) All permanent in-plant roads and vehicle work areas shall be watered, treated with dust suppressant chemicals, oiled or paved and cleaned as necessary to achieve maximum control of dust emissions.
(d) Before construction begins, the owner or operator shall file with the appropriate Regional Office a completed Form PI-7 and supporting documentation demonstrating that all of the requirements of the exemption will be met.

93. Any temporarily located concrete facility that accomplishes wet batching, dry batching or central mixing and operates according to the following conditions:

(a) A fabric filter(s) with a maximum filtering velocity of 4.0 ft/min shall be installed on each bulk storage silo or the silo is vented to the central collection system specified in condition (f).
(b) The cement weight hopper shall be vented to a control device which eliminates visible emissions or vented inside the charging hopper of the transit mix truck if controlled by a suction shroud.
(c) A visible and/or audible warning mechanism shall be installed on each silo for warning operators that the silo is full, so that it will not be overloaded at any time.
(d) All in-plant roads (batch truck and material delivery truck roads) and area between stockpiles and conveyor hopper shall be watered, oiled or paved and cleaned as necessary to achieve maximum control of dust emissions.
(e) All stockpiles shall be sprinkled with water and/or chemicals as necessary to achieve maximum control of dust emissions.
(f) Loading of rotary mix trucks at wet batch plants shall be through a discharge spout equipped with a water ring that controls dust emissions or a suction shroud which is vented to a central collection system with a minimum of 4,000 acfm of air to a fabric filter with air cleaning and a 7.0 ft/min maximum filtering velocity or automatic sequenced mechanical cleaning and a 5.25 ft/min maximum filtering velocity.
(g) Dust emissions from the loading of open-bodied trucks at the batch drop point of dry batch plants or dust emissions from the drum feed for central mix plants shall be controlled by a suction shroud which is vented to a central collection system with a minimum of 4,000 acfm of air to a fabric filter with air cleaning and a 7.0 ft/min maximum filtering velocity or automatic sequenced mechanical cleaning and a 5.25 ft/min maximum filtering velocity. Suction shrouds on dry batch plants shall be utilized so as to allow for closure over the receiving vehicle compartment or bed.
(h) Spillage of cement and fly ash used in the batch shall be immediately cleaned up and contained or dampened such that dust emissions from wind erosion and/or vehicle traffic are minimized.
(i) All open-bodied vehicles transporting material from any dry batch plant to paving mixer(s) shall be loaded with a final layer of wet sand and/or the truck shall be covered with a tarp to achieve maximum control of dust emissions.
(j) The facility (including associated stationary equipment and stockpiles) is located at least 300 feet from any recreational area or residence or any other structure not occupied or used solely by the owner of the property upon which the facility is located. This does not apply to plants that are set up specifically to pour concrete for a particular construction project and the facility is on or adjacent to the construction site.
(k) Unless the facility is to be located temporarily in the right-of-way of a public works project, public notice and opportunity for public hearing, as specified in 116.7(b)(2) and (3), has been published and documentation thereof has been provided to the Texas Air Control Board (TACB).
(l) Before construction of the facility begins, written site approval is received from the Executive Director of the Texas Air Control Board.
(m) Before construction begins, the facility shall be registered with the appropriate Regional Office using Form PI-7 including a current Table 20.
(n) The appropriate Regional Office and local program shall be notified within 10 days after the date of the actual start of operation.

94. Any soil stabilization facility that operates according to the following conditions:

(a) Fabric filter(s) with a maximum filtering velocity of 4.0 feet per minute shall be installed on each storage silo.
(b) All conveyor belt(s) transferring dry material to the pug mill shall be top covered.
(c) The pug mill used to mix the materials shall be covered.
(d) All permanent in-plant roads and vehicle work areas shall be watered, oiled or paved and cleaned as necessary to achieve maximum control of dust emissions.
(e) A mechanism is installed on the storage silo(s) to notify operators that the silo is full, so it is not overloaded at any time.
(f) All stockpiles are sprinkled with water and/or chemicals as necessary to achieve maximum control of dust emissions.
(g) When emulsified asphalt is used as the stabilizing admixture, the emulsified asphalt shall be stored in a container used exclusively for emulsified asphalt storage. Transfer of emulsified asphalt from the storage tank to the pug mill shall be accomplished by means of a pump and metering device.
(h) Before construction of the facility begins, written site approval shall be received from the Executive Director of the Texas Air Control Board and the facility shall be registered with the appropriate Regional Office using Form PI-7.
(i) The facility is located at least 300 feet from any recreational area or residence or any other structure not occupied or used solely by the owner of the facility or the owner of the property upon which the facility is located. This does not apply to plants that are set up specifically to pour material for a particular construction project and the facility is on or adjacent to the construction site.

95. Uranium in-situ solution recovery facility producing yellowcake provided that the facility operates according to the following conditions:

(a) The facility is located at least 1/4 mile from any recreational area or residence or other structure not occupied or used solely by the owner of the facility or the owner of the property upon which the facility is located.
(b) The facility shall have no emissions other than (a) ammonia which shall not exceed an emission rate of 2 pounds per hour and (b) particulate dust from yellowcake drying not to exceed 0.1 pound per hour.
(c) The facility shall have no visible particulate emissions from any part of the process.
(d) Before construction begins the facility must be registered with the appropriate Regional Office using Form PI-7.

96. Dry hearth reverberatory type holding chamber aluminum or copper metal reclamation/sweat furnaces in which no fluxing, degassing or refining is conducted, which operate according to the following conditions and limitations:

(a) Scrap metal charges shall consist primarily of copper or aluminum metal. Operation of the furnace for reclamation or lead, tin, zinc or magnesium metals is prohibited.
(b) The maximum furnace charging rate shall be 2000 pounds per hour or less.
(c) The furnace charge door shall remain closed except during charging and furnace cleaning operations.
(d) The furnace shall be equipped with an afterburner which will provide a minimum retention time of 0.1 second at a minimum temperature of 1300F for all furnace exhaust gases.
(e) The incineration of any insulated wire or cable containing chlorine compounds in the insulation, such as Polyvinyl chloride insulation, is expressly prohibited.
(f) The owner or operator of the furnace shall initiate and maintain a program of furnace operator training in the recognition of chlorine-bearing wire or cable insulation and shall demonstrate upon request by the Executive Director, acceptable proficiency in the recognition of chlorine-bearing wire or cable insulation, such as Polyvinyl Chloride insulation.
(g) Fuel for the furnace shall be sweet natural gas as defined in General rules adopted by the Texas Air Control Board or liquid petroleum gas, diesel or No. 2 fuel oil.
(h) Before construction begins the facility shall be registered with Form PI-7.

97. Any trench burner that operates according to the following conditions:

(a) The trench burner shall be operated at least 300 feet from any recreational area, residence or other structure not occupied or used solely by the owner of the trench burner or the owner of the property upon which the trench burner is located.
(b) The trench shall be opened in undisturbed soil not previously excavated, built up, compacted or used in any type of landfill operation.
(c) The trench shall be no wider than 12 feet with a minimum depth of 10 feet. The maximum length of the burning area as measured along the bottom of the trench shall not exceed by more than 5 feet the length of the manifold. The walls for the trench must be maintained such that they remain vertical.
(d) Operation of this trench burner is limited to the hours between 8:00 a.m. and 6:00 p.m., and is limited to a total of 8 hours per day and 1000 hours per year. A written record or log of the hours of operation of this trench burner shall be maintained at the site and made available at the request of personnel from the Texas Air Control Board or any local air pollution control program having jurisdiction. This record or log shall be organized such that the compliance status of this special condition can be readily determined.
(e) Material shall not be added to the trench such that the material will not be consumed by 6:00 p.m.
(f) The blower shall remain on until all material is consumed so that any remaining material in the trench will not smoke when the blower is turned off.
(g) This trench burner shall not be operated when an air stagnation advisory is in effect for the area in which the trench burner is located.
(h) Opacity of emissions from the trench and from operation of the blower shall not exceed 20% averaged over a five-minute period, except for a start-up period which shall not exceed 20 minutes. Opacity shall be measured as outlined in Chapter 13, "Visible Emissions Evaluation," of the Texas Air Control Board Sampling Procedures Manual, as published in January 1983, and as subsequently revised.
(i) Material to be burned in the trench is limited to not more than 7 tons per hour of trees, brush and untreated lumber. Material not being worked and material being stockpiled to be burned at a later date must be kept at least 75 feet from the trench.
(j) Material shall not be added to the trench in such a manner as to be stacked above the air curtain at any time.
(k) The ash generated by this operation shall be removed from the trench as necessary in order to maintain the minimum trench depth of 10 feet. The ash shall be removed in such a manner as to minimize the ash becoming airborne. All material removed from the trench must be completely extinguished before being landfilled or placed in contact with combustible material to prevent combustion outside of the trench or in the landfill.
(l) A copy of this exemption shall be kept at the burn site and made available at the request of personnel from the Texas Air Control Board or any local air pollution control program having jurisdiction.
(m) Operating instructions shall be posted at the burn site and all operators shall read and have knowledge of these instructions. The operating instructions shall be made available at the request of personnel from the Texas Air Control Board or any local air pollution control program having jurisdiction.
(n) An operator shall remain with the trench burner at all times when it is operating.
(o) Upon notification by a representative of the Texas Air Control Board or any local air pollution control program having jurisdiction that the trench burner is not complying with the conditions of this exemption, no additional material shall be added to the trench until compliance with such conditions has been effected.
(p) The Texas Department of Health (TDH) shall be notified by the owner or operator of the trench burner prior to use of the trench burner at a TDH permitted landfill.
(q) Upon removal of the trench burner from the burn site, the trench shall be completely filled uncombustible material.
(r) Before operation of the facility begins at any site, written site approval shall be received from the Executive Director of the Texas Air Control Board and any local air pollution control program having jurisdiction in the area and the facility shall be registered with Form PI-7.

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