9

PERMIT MEMORANDUM No. 2005-257-O DRAFT

OKLAHOMA DEPARTMENT OF ENVIRONMENTAL QUALITY

AIR QUALITY DIVISION

MEMORANDUM January 26, 2006

TO: Dawson Lasseter, P.E., Chief Engineer, Air Quality

THROUGH: Richard Kienlen, P.E., Engr. Mgr. II, New Source Permits Section

THROUGH: Peer Review, David Pollard, Regional Office at Tulsa

FROM: Herb Neumann, Regional Office at Tulsa

SUBJECT: Evaluation of Permit No. 2005-257-O

Green Country Marble, Inc.

Manufacture of Molded Bath, Sink, & Lavatory Fixtures

600 W. 158th Street, Glenpool, Tulsa County

INTRODUCTION

Green Country has submitted an application to operate a facility that manufactures vanity tops, sinks, and other fixtures (SIC 3089) from “cultured marble.” This type of operation has the potential to emit styrene, a HAP, in excess of 10 TPY, which would make it a major source under 40 CFR 63. Applicant wishes to obtain a “synthetic” minor permit; that is, a permit with federally enforceable conditions limiting them to emissions below the major source threshold. Such a permit and conditions should establish that the facility is not subject to the requirements of MACT WWWW (Reinforced Plastic Composites Production). The company has operated in Tulsa County for an indeterminate period, but commenced operations at this new facility in May 2005. This application was received within the “grace period,” so Compliance/Enforcement took no action.

PROCESS DESCRIPTION

Fixtures are formed by filling molds with “cultured marble.” Cultured marble is a blend of crushed limestone (calcium carbonate), styrene-based resin, and catalyst. The process starts by cleaning the molds with acetone and applying a mold release agent. A layer of gelcoat is then sprayed into each mold and the mold is cured by passing through a drying tunnel. The cured mold is placed on a vibrating table and the cultured marble is poured. The material being poured is variously known as back-fill compound or matrix composite. Composite at this facility will be blended and mixed in set ratios by a metering and mixing system known as the Auto-Caster. Computerized control assures optimum characteristics for each batch. Composite is dispensed into a bucket, from which it is poured into the molds. The product is allowed to cure or harden overnight and is removed from the mold the next day. The empty mold is prepared for reuse and the part goes to a grinding booth. Excess material is removed by grinding. Additional buffing and polishing is done as necessary, and the part is wrapped and ready for shipment.

Emissions of volatile organic compounds occur during spraying or molding. Styrene is the most significant emission from the spraying/molding process. Grinding processes will cause particulate emissions. Acetone is the primary cleaner used for buckets and tools. There are no emission controls on any process. Unsalvageable material will be in a solid form and will be disposed of as municipal waste.

EQUIPMENT

Spray Booth

There is a single spray booth for application of gelcoat. An atomized spray gun applies the layer of gelcoat. The booth has a 36²-diameter stack that vents 10,000 acfm at 28¢ above grade at ambient temperature. VOC emissions from mold cleaning are assumed to be emitted through this stack, due to the proximity of the cleaning operation to this stack.

Resin Application

As mentioned above, the Auto-Caster provides a computer-defined mix of resin and catalyst to buckets that are manually taken to the point where pouring occurs. There is no stack for the Auto-Caster, so emissions are considered to occur at the gelcoat spray booth, due to its proximity.

Others

There are several activities with very small emissions, such as the 0.20 MMBTUH natural gas-fired drying tunnel, grinding, and clean up. The drying tunnel vents 10,000 acfm to atmosphere at 28¢ above grade through a 36²-diameter stack. The grinding booth also vents 10,000 acfm to atmosphere at 28¢ above grade through a 36²-diameter stack. It has a filter rated at 96.4% capture efficiency.

EMISSIONS

Spray booth and resin application

There are uncontrolled VOC emissions from spraying gelcoat and from pouring wet resin materials. The chemical basis for this industry is that the mixed and catalyzed materials cause volatiles to be polymerized into the wet material, restricting their free emission. Styrene emission factors are taken from Table 1 of 40 CFR Part 63, Subpart WWWW, the NESHAP for Reinforced Plastic Composites Production. Gelcoat used at this facility will be non-vapor suppressed, atomized spray, and emission factors used for gelcoat reflect these conditions. Composite from the Auto-Caster is non-vapor suppressed, but is manually applied, and emission factors used for composite reflect these conditions. Styrene content and the related emission factor are contained in the following table. Material amounts are estimated maximum throughputs or requested permit amounts. Hourly rates reflect the maximum Auto-Caster rate of 3,600 lbs/hr and the maximum gelcoat spray gun rate of 1,200 lbs/hr. These numbers are many times higher than the capability of the facility to use the materials. For instance, the annual authorized resin amount would be exhausted after only eleven 8-hour shifts and the gelcoat would be gone after another 12 shifts. Although styrene usage during the year is based on maximum production capacity of the facility, the hourly figures may still be used to calculate a relatively meaningless annual potential-to-emit (PTE). The facility has requested limits on annual use that are projected to maintain the facility’s synthetic minor status. Small amounts of HAP and VOC are contained in the catalyst and in other products, such as mold release agents, etc. Review of MSD sheets suggests that combined emissions of these constituents total less than one TPY and they will be ignored for this analysis. The principal cleaning solvent used is acetone, which is not a HAP or VOC. Its emissions are calculated to be approximately 2 TPY.

STYRENE EMISSIONS

Material

/ Lbs/yr / Styrene content / Emission factor / Emissions / PTE TPY
Lbs/hr / TPY
Neste Poly Marble Clear Gelcoat / 28,000 / 47% / 584.27 lb/ton / 351 / 4.09 / 1,535
Cook Stypol 040-5739 Resin / 320,000 / 28.51% / 71.85 lb/ton / 129 / 5.75 / 566
Totals / 480 / 9.84 / 2,102

Assuming that 10% of the gelcoat is PM overspray and that the filter has efficiency of 95% leads to 28,000 lbs/yr × 10% × (1 – 95%) = 140 lbs/yr or 0.07 TPY of PM.

Other activities

The 0.20 MMBTUH drying tunnel is fired by natural gas. Using emission factors from Tables 1.4-1 and 2 of AP-42 (7/98) yields the following emissions. Annual TPY is based on eight hours per day, six days per week, and 52 weeks per year.

Pollutant / Factor
Lbs/MMCF / Emissions
Lb/hr / TPY / PTE (TPY)
NOX / 100 / 0.02 / 0.03 / 0.09
CO / 84 / 0.02 / 0.02 / 0.07
SO2 / 0.6 / <.01 / <.01 / <.01
VOC / 5.5 / <.01 / <.01 / <.01
Total PM / 7.6 / <.01 / <.01 / 0.01

Fabric filters with 96.4% efficiency capture particulate matter emitted from the grinding booth. Assuming that 1% of all material produced is lost to grinding, PM emissions are

857,143 lbs/yr × 0.01 × (1 – 0.964) = 308 lbs/yr or 0.154 TPY.

To summarize facility-wide emissions, VOC emissions are expected to be approximately 11 TPY, most of which is styrene, a HAP, whose authorized emissions are 9.84 TPY. Emissions of all other criteria pollutants are negligible.


OKLAHOMA AIR POLLUTION CONTROL RULES

OAC 252:100-1 (General Provisions) [Applicable]

Subchapter 1 includes definitions but there are no regulatory requirements.

OAC 252:100-3 (Air Quality Standards and Increments) [Applicable]

Subchapter 3 enumerates the primary and secondary ambient air quality standards and the significant deterioration increments. At this time, all of Oklahoma is in “attainment” of these standards.

OAC 252:100-4 (New Source Performance Standards) [Not Applicable]

Federal regulations in 40 CFR Part 60 are incorporated by reference as they exist on July 1, 2002, except for the following: Subpart A (Sections 60.4, 60.9, 60.10, and 60.16), Subpart B, Subpart C, Subpart Ca, Subpart Cb, Subpart Cc, Subpart Cd, Subpart Ce, Subpart AAA, and Appendix G. These requirements are addressed in the “Federal Regulations” section.

OAC 252:100-5 (Registration, Emission Inventory, and Annual Operating Fees) [Applicable]

Subchapter 5 requires sources of air contaminants to register with Air Quality, file emission inventories annually, and pay annual operating fees based upon total annual emissions of regulated pollutants. Required annual information (Turn-Around Document) shall be provided to Air Quality.

OAC 252:100-7 (Permits for Minor Facilities) [Applicable]

Subchapter 7 sets forth the permit application fees and the basic substantive requirements of permits for minor facilities. Since criteria pollutant emissions are less than 100 TPY for each pollutant, and emissions of Hazardous Air Pollutants (HAP) do not exceed 10 TPY for any one HAP or 25 TPY for any aggregate of HAP, the facility is defined as a minor source. As such, BACT is not required. Although this facility has actual emissions below the 40 TPY threshold required to be exempt from permitting, it has potential emissions of styrene greater than the 10 TPY major source threshold for HAP, and requires a permit containing federally enforceable conditions that establish it as a “synthetic” minor source.

OAC 252:100-9 (Excess Emissions Reporting Requirements) [Applicable]

In the event of any release which results in excess emissions, the owner or operator of such facility shall notify the Air Quality Division as soon as the owner or operator of the facility has knowledge of such emissions, but no later than 4:30 p.m. the next working day. Within ten (10) working days after the immediate notice is given, the owner or operator shall submit a written report describing the extent of the excess emissions and response actions taken by the facility.

OAC 252:100-13 (Open Burning) [Applicable]

Open burning of refuse and other combustible material is prohibited except as authorized in the specific examples and under the conditions listed in this subchapter.

OAC 252:100-19 (Particulate Matter (PM)) [Applicable]

Section 19-4 regulates emissions of PM from new and existing fuel-burning equipment, with emission limits based on maximum design heat input rating. Appendix C specifies a PM emission limitation of 0.60 lbs/MMBTU for all equipment at this facility with a heat input rating of 10 Million BTU per hour (MMBTUH) or less. Fuel-burning equipment is defined in OAC 252:100-1 as “combustion devices used to convert fuel or wastes to usable heat or power.” Thus, the drying tunnel is subject to the requirements of this subchapter. Table 1.4-2 of AP-42 (7/98) lists natural gas total PM emissions to be 7.6 lbs/million scf or about 0.0076 lbs/MMBTU, which is in compliance.

Section 19-12 limits particulate emissions from emission points in an industrial process based on process weight rate, as specified in Appendix G. This facility will have a process weight rate of 4.4 TPH, and the particulate emission limitation for this rate is 11 lbs/hr. PM emissions for the gelcoat operation are estimated at 6 lbs/hr, which is in compliance with the limitation.

OAC 252:100-25 (Visible Emissions and Particulates) [Applicable]

No discharge of greater than 20% opacity is allowed except for short-term occurrences that consist of not more than one six-minute period in any consecutive 60 minutes, not to exceed three such periods in any consecutive 24 hours. In no case shall the average of any six-minute period exceed 60% opacity. Under normal operating conditions, this facility has negligible potential to violate this requirement; therefore it is not necessary to require specific precautions to be taken.

OAC 252:100-29 (Fugitive Dust) [Applicable]

No person shall cause or permit the discharge of any visible fugitive dust emissions beyond the property line on which the emissions originate in such a manner as to damage or to interfere with the use of adjacent properties, or cause air quality standards to be exceeded, or interfere with the maintenance of air quality standards. Under normal operating conditions, this facility has negligible potential to violate this requirement; therefore it is not necessary to require specific precautions to be taken.

OAC 252:100-31 (Sulfur Oxides) [Applicable]

Part 5 The new equipment standard for emissions of oxides of sulfur measured as sulfur dioxide from gas-fired fuel-burning equipment is 0.2 pounds per MMBTU heat input, maximum three-hour average. The drying tunnel uses natural gas, and Table 1.4-2 of AP-42 (7/98), lists natural gas SO2 emissions to be 0.6 lbs/MMft3 or about 0.0006 lbs/MMBTU, which is in compliance.

OAC 252:100-33 (Nitrogen Oxides) [Not Applicable]

This subchapter limits new gas-fired fuel-burning equipment with rated heat input greater than or equal to 50 MMBTUH to emissions of 0.20 lbs of NOx per MMBTU, three-hour average. There are no equipment items that exceed the 50 MMBTUH threshold.

OAC 252:100-35 (Carbon Monoxide) [Not Applicable]

None of the following affected processes are located at this facility: gray iron cupola, blast furnace, basic oxygen furnace, petroleum catalytic cracking unit, or petroleum catalytic reforming unit.

OAC 252:100-37 (Volatile Organic Compounds) [Not Applicable]

Part 3 The facility contains two 2,000-gallon styrene storage tanks. Styrene vapor pressure is significantly less than 1.5 psia, making it exempt from this section per §37-4.

Part 5 limits the VOC content of coating used in coating lines or operations. This facility does not normally conduct coating or painting operations except for routine maintenance of the facility and equipment, which is exempt.

Part 7 This facility contains none of the specific processes listed in Part 7.

OAC 252:100-39 (VOCs in Nonattainment and Former Nonattainment Areas) [Not Applicable]

This subchapter imposes additional conditions beyond those of Subchapter 37 on emissions of organic materials from new and existing facilities in Tulsa County.

Part 7 Storage of VOC is discussed in Section 39-41. The facility contains two 2,000-gallon styrene storage tanks. Styrene vapor pressure is significantly less than 1.5 psia, making it exempt from this section per §39-4.

OAC 252:100-41 (Hazardous Air Pollutants) [Not Applicable]

Part 3 addresses hazardous air contaminants. NESHAP, as found in 40 CFR Part 61, are adopted by reference as they exist on September 1, 2004, with the exception of Subparts B, H, I, K, Q, R, T, W and Appendices D and E, all of which address radionuclides. In addition, General Provisions as found in 40 CFR Part 63, Subpart A, and the Maximum Achievable Control Technology (MACT) standards as found in 40 CFR Part 63, Subparts F, G, H, I, J, L, M, N, O, Q, R, S, T, U, W, X, Y, AA, BB, CC, DD, EE, GG, HH, II, JJ, KK, LL, MM, OO, PP, QQ, RR, SS, TT, UU, VV, WW, XX, YY, CCC, DDD, EEE, GGG, HHH, III, JJJ, LLL, MMM, NNN, OOO, PPP, QQQ, RRR, TTT, UUU, VVV, XXX, AAAA, CCCC, DDDD, EEEE, FFFF, GGGG, HHHH, IIII, JJJJ, KKKK, MMMM, NNNN, OOOO, PPPP, QQQQ, RRRR, SSSS, TTTT, UUUU, VVVV, WWWW, XXXX, YYYY, ZZZZ, AAAAA, BBBBB, CCCCC, EEEEE, FFFFF, GGGGG, HHHHH, IIIII, JJJJJ, KKKKK, LLLLL, MMMMM, NNNNN, PPPPP, QQQQQ, RRRRR, SSSSS and TTTTT are hereby adopted by reference as they exist on September 1, 2004. These standards apply to both existing and new sources of HAPs. These requirements are covered in the “Federal Regulations” section.