326 IAC 2-9-7 Sand and gravel plants

Sec. 7. (a) The following definitions apply throughout this section: (1) "Annual throughput" means the amount of material that is being processed through the plant on a calendar year basis. (2) "Sand and gravel" means any unconsolidated mixture of fine or coarse aggregate, or both, found in and processed from a natural deposit. (3) "Surfactant" means any chemical additive that reduces the surface tension of water. (4) "Wet process in a pit and quarry operation" means the operation in which the aggregate deposit being processed has: (A) been mined from beneath bodies of water, such as: (i) rivers; (ii) estuaries; (iii) lakes; or (iv) oceans; or (B) a free moisture content of one and five-tenths percent (1.5%) by weight or greater. The aggregate infeed that undergoes such process shall maintain a minimum of one and five-tenths percent (1.5%) by weight throughout the production process. (5) "Wet suppression systems" means dust control devices in a pit and quarry operation that use a pressurized liquid, either water or water with a small amount of surfactant, for the controlled reduction or elimination of airborne dust or the suppression of such dust at its source. (b) Any sand and gravel plant may elect to be subject to this section by complying with the requirements of section 1 of this rule and meeting the following conditions, outlined under subdivisions (1) through (4), as applicable, and subdivision (5): (1) Sand and gravel plants that do not emit particulate matter in excess of or equal to twenty-five (25) tons per year, including fugitive particulate emissions, utilizing at most five (5) crushers, ten (10) screens, and a conveying operation shall limit the annual throughput to less than four hundred ten thousand (410,000) tons per year. (2) Sand and gravel plants that do not emit particulate matter in excess of or equal to twenty-five (25) tons per year, excluding fugitive particulate emissions utilizing at most nine (9) crushers, twenty (20) screens, and a conveying operation shall limit the annual throughput to less than one million (1,000,000) tons per year. (3) Sand and gravel plants that do not emit particulate matter in excess of or equal to one hundred (100) tons per year, excluding fugitive particulate emissions, utilizing at most twelve (12) crushers, twenty-four (24) screens, and a conveying operation shall limit the annual throughput to less than three million one hundred thousand (3,100,000) tons per year. (4) Sand and gravel plants that meet the specific restrictions and conditions in subdivision (1), (2), or (3) shall also comply with the following provisions: (A) Each source described by subdivisions (1) and (2) shall maintain annual throughput records at the site on a calendar year basis. (B) Each source described by subdivision (3) shall maintain at the site throughput records for the previous twelve (12) months on a monthly rolling total. (C) A wet process or continuous wet suppressions shall be used. (D) All manufacturing equipment that generates particulate emissions and control devices shall be operated and maintained at all times of plant operation in such a manner as to meet the requirements of this rule. (E) Visible emissions from the screening and conveying operations shall not exceed an average of ten percent (10%) opacity in twenty-four (24) consecutive readings in a six (6) minute period, and visible emissions from the crushing operation shall not exceed an average of fifteen percent (15%) opacity in twenty-four (24) consecutive readings in a six (6) minute period. Compliance with these limitations shall be determined by 40 CFR 60, Appendix A, Method 9*. (F) Fugitive particulate emissions shall be controlled by applying water on storage piles and unpaved roadways on an as needed basis, such that the following visible emission conditions are met: (i) Visible emissions from storage piles shall not exceed twenty percent (20%) in twenty-four (24) consecutive readings in a six (6) minute period. This limitation shall not apply during periods when application of control measures are ineffective or unreasonable due to sustained high wind speeds. The opacity shall be determined using 40 CFR 60, Appendix A, Method 9*, except that the opacity shall be observed at approximately four (4) feet from the surface at the point of maximum opacity. The observer shall stand at least fifteen (15) feet, but not more than one-fourth (1/4) mile, from the plume and at approximately right angles to the plume. (ii) Visible emissions from unpaved roadways shall not exceed an average instantaneous opacity of twenty percent (20%). Average instantaneous opacity shall be the average of twelve (12) instantaneous opacity readings, taken for four (4) vehicle passes, consisting of three (3) opacity readings for each vehicle pass. The three (3) opacity readings for each vehicle pass shall be taken as follows: (AA) The first shall be taken at the time of emission generation. (BB) The second shall be taken five (5) seconds after the first. (CC) The third shall be taken five (5) seconds after the second or ten (10) seconds after the first. The three (3) readings shall be taken at approximately four (4) feet from the surface at the point of maximum opacity. The observer shall stand at least fifteen (15) feet, but not more than one-fourth (1/4) mile, from the plume and at approximately right angles to the plume. (G) Fugitive particulate emissions at a sand and gravel plant shall not escape beyond the property line or boundaries of the property, right-of-way, or easement on which the source is located pursuant to 326 IAC 6-4. (H) The source shall comply with 40 CFR 60.670, Standards of Performance for Nonmetallic Mineral Processing Plants*, if applicable. (5) Request a source specific operating agreement under this section. *These documents are incorporated by reference. Copies may be obtained from the Government Printing Office, 732 North Capitol Street NW, Washington, D.C. 20401 or are available for review and copying at the Indiana Department of Environmental Management, Office of Air Quality, Indiana Government Center North, Tenth Floor, 100 North Senate Avenue, Indianapolis, Indiana 46204.