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Engineering Summary New NGC, Inc. Application #: FY04-0335 AFS #: 3301500045 County: Rockingham Engineer: Laughton Date: March 2004 Permitting Background/History New NGC, Inc. (NGC), formerly known as National Gypsum or Gold Bond Building Products, owns and operates a small gypsum wallboard manufacturing plant on Michael Succi Drive in Portsmouth, NH. This facility has been in operation since the early 1970’s. In 1985 the facility conducted a modernization project adding several pieces of new equipment and removed the old Gypsum Wallboard Drying Kiln Zones 1 through 7. Temporary Permits were issued by DES for the installation and initial operation of the following new equipment in 1985: Raymond Mill #2; New Hot Stucco Handling System; Board Plant Silo & Feed System; Dry Additive Handling System; Pin Mixer (Distribution box on the wet end of the board drying kiln); Gypsum Wallboard Drying Kiln Zones 1 through 4; Board End Trim System; Riser Maker/Chopper System; and a Dry Waste Reclaim System. On June 25, 1996 the facility submitted a federally enforceable state operating permit application to DES. In it’s application, NGC indicated it had the potential to emit NOx and SO2 at greater than major source thresholds of 50 and 100 tons per year respectively, but was willing to take federally enforceable emissions limitations to keep it as a synthetic minor source for these two pollutants. NGC had conducted testing on the gypsum wallboard drying kiln while firing natural gas in July 1994 and No. 2 fuel oil in June 1995. DES evaluated the NOx RACT source status of the NGC facility in 1997. As part of the review, DES pointed out that previous testing in 1994 and 1995 consisted of a single 1-hour test for each of the 4 dryer zone stacks on the board drying kiln and not the required three one hour runs. DES also pointed out that the variability in oxygen content of the stack gases during a short duration test would have a large impact on the Fd calculation method utilized for lb/MMBtu calculations. If DES used those stack test data with the actual fuel usage in 1994 it would result in NOx emissions of 52 tons. DES suggested that the facility retest the board drying kiln for natural gas and No. 2 fuel oil and conduct three one-hour runs. NGC retested the board drying kiln while firing natural gas and No. 2 fuel oil on June 11-12, 1997. DES then re-looked at facility wide emissions for 1994 and determined that the calculated actual facility wide emissions for 1994, the year of highest fuel use since 1989, were less than 50 tons per year. Pursuant to Env-A 1211.02(n), any stationary source having combined theoretical potential emissions of 50 tons or more of NOx during any consecutive 12 month period but whose actual NOx emissions have not equaled or exceeded 50 tons during any consecutive 12 month period since January 1, 1989, can take permit limitations to “opt out” of the requirements of NOx RACT. DES issued the FESOP permit number FP-S-0057 on April 30, 1999 to NGC which contained a 50 ton NOx per consecutive 12 month period emissions limitation facility wide and incorporated a maximum No. 2 fuel oil usage limit of 1,250,000 gallons in any consecutive 12 month period to keep the facility below both the 100 tons SO2 and 50 tons NOx emissions per consecutive 12 month period. This fuel use limitation was recalculated for No. 2 fuel oil with a maximum sulfur content of 0.3% sulfur by weight and found to be 4,690,000 gallons. Also note that the four Calcidyne Units (#2, #3, #4, and #5) are less than the permitting threshold of 10

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MMBtu/hr gross heat input rate while firing natural gas or No. 2 fuel oil, but are included as permitted devices in the permit, as their fuel use must be included in the combined fuel limit for the facility to opt out of NOx RACT requirements and their particulate matter emissions contain gypsum, a regulated toxic air pollutant. In addition to keeping actual emissions below the above mentioned limits, the facility must remain in full compliance with the conditions of the permit issued by DES in order to stay out of NOx RACT requirements. On August 3, 1999, DES did some minor permit amendments at the request of NGC. DES added a reference to 40 CFR 60 Subpart OOO Recordkeeping and Reporting Requirements in the permit in Section X – Recordkeeping and Reporting. DES left out the specific Subpart OOO Recordkeeping and Reporting regulatory citation, which is 60.676. In addition, a couple of stacks had heights above ground level and/or orientation changed to reflect the most recent ambient air dispersion modeling analysis performed. On March 28, 2002, NGC submitted a permit application for an energy optimization project on the gypsum wallboard drying kiln. This project simply was for recycling heat and to reduce fossil fuel consumption of the drying kiln. This was accomplished by returning exhaust gases from the first two Zones, Zones 1 and 2, to be used as the makeup air to Zone 4. Hence, gaseous emissions from Zones 1, 2, and 4 are now exhausted through one new stack and the existing Zone 3 still exhausts through its existing stack. In addition, the facility opted for a lower maximum sulfur content restriction on No. 2 fuel oil of 0.3% sulfur by weight. DES and Trinity Consultants, Inc. remodeled the facility including the changes to the stacks on the gypsum wallboard drying kiln and to reflect the change in the lower maximum sulfur content restriction for No. 2 fuel oil of 0.3% sulfur by weight. Current Permit Application FY04-0335 & Air Toxics Evaluation for Gypsum DES sent a permit renewal reminder letter dated October 23, 2003, indicating the facility should submit a renewal application prior to January 31, 2004. As part of the permit renewal, Trinity Consultants (Trinity), working on behalf of NGC, has been in contact with Jim Black regarding its ambient air dispersion modeling analysis protocol. In Trinity’s January 19, 2004 Memorandum to Jim Black, it mentions a May 30, 2003 letter from DES to NGC requesting an air toxics evaluation for gypsum. Trinity proposed for each emission source with the exception of the Rock Dryer, the two Raymond Mills, and the four Calcidynes units, the gypsum emission rates to be modeled as equal to the permitted limits of total suspended particulate matter in the current state permit to operate FP-S-0057. For the Rock Dryer, Raymond Mills, and Calcidynes, the gypsum emissions rates to be modeled are at rates equal to 1.15 times the AP-42 emission factor multiplied by the permitted maximum material throughput rates of these devices. It should be noted that the current state permit to operate has permitted total suspended particulate matter emission rates for the Rock Dryer, two Raymond Mills, and four Calcidynes units at 1.5 times the AP-42 emission factor multiplied by the permitted maximum material throughput rates of these devices. The permit Engineer has conducted an extensive review of previous permits issued, permit applications dating back to 1984, engineering calculations from National Gypsum in reference to baghouses from most all process sources at the facility, AP-42 emissions factors for Gypsum Wallboard Manufacturing facilities, ambient air dispersion modeling analyses conducted by DES in August 1995, September 1998, September 2002, and stack testing conducted at the Portsmouth facility or at similar process devices in other National Gypsum wallboard

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manufacturing plants in order to determine/establish criteria pollutant permitted maximum emission rates and gypsum emissions rates to be modeled as part of a compliance demonstration with the state air toxics program. Please refer to the 19 page New NGC, Inc. Emissions Information supplement to see all background emissions limitations information. In addition, please refer to the 6 page summary of this information, with the final permitted maximum emissions limitations that were selected and the basis of their selection. Below is a summary table of Emissions Limitations for all process devices at the facility and notes explaining specifics for each process device.

Table 2 Emission Limitations for Criteria Pollutants

Device CO NOx PM10 SO2 VOCs Hourly Emission Limitations (lb/hr)

Rock Crusher NA NA NA NA NA

Rock Dryer 0.66 (gas) 7.08 (oil)

0.48 (gas) 0.89 (oil) 1.68 (gas & oil) 0.15 (gas)

4.56 (oil) 0.08 (gas) 0.02 (oil)

Calcidynes #2, #3, #4, & #5

0.56 (gas) 0.25 (oil)

0.67 (gas) 1.00 (oil) 0.40 (gas and oil) 2.02 (gas)

3.87 (oil) 0.04 (gas) 0.01 (oil)

Gypsum Board Drying Kiln

11.01 (gas) 3.56 (oil)

7.98 (gas) 22.33 (oil)

0.52 (gas) 1.03 (oil)

0.04 (gas) 21.91 (oil)

0.38 (gas) 0.11 (oil)

Raymond Mill #1 NA NA 2.76 NA NA

Raymond Mill #2 NA NA 2.76 & 0.05 gr/dscm NA NA

Old Hot Stucco System NA NA 0.21 NA NA New Hot Stucco System NA NA 0.55 NA NA

Board Plant Silo & Feed System NA NA 0.50 NA NA

Dry Additive Handling System NA NA 0.48 NA NA

Board End Trim System NA NA 0.57 NA NA Riser Maker/Chopper System NA NA 1.03 NA NA

Annual Emission Limitations (tpy) Facility Wide < 100 < 50 < 100 < 100 < 50

Notes to Table 2: 1. Note that PM10 emissions limits in this Table account for all total suspended

particulate (TSP) matter emissions. 2. PM10 emissions limits for the Rock Dryer are based on use of USEPA AP-42

(July 1993), Section 11.16, Gypsum Manufacturing emission factor of 0.04 lb PM/ton and max production rate of 42.0 ton/hr. NOx (gas and oil), CO (gas and oil), and SO2 (gas) emissions limits for the Rock Dryer are based on testing conducted at another similar National Gypsum facility plus a 10% safety factor added. The Rock Dryer VOC (gas and oil) and SO2 emissions limit while firing oil is based on use of USEPA AP-42 (5th Edition 1/1995, updated 9/98), Section 1.3, Fuel Oil Combustion with 0.3% sulfur content emissions factors for external combustion boilers < 100 MMBtu/hr.

3. PM10 emissions limits for the Calcidynes while firing gas or oil are based on use of USEPA AP-42 (July 1993), Section 11.16, Gypsum Manufacturing emission

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factor of 0.04 lb PM/ton and max production rate of 10.0 ton/hr. NOx, CO, and VOC emissions limits while firing gas or oil were based on use of USEPA AP-42 (5th Edition 1/1995, updated 9/98), Sections 1.3 & 1.4, Fuel Oil Combustion & Natural Gas Combustion, emission factors for external combustion boilers < 100 MMBtu/hr. SO2 emissions limits while firing gas or oil were based on testing from another National Gypsum facility plus a 10% safety factor added.

4. PM10, SO2, and VOC emissions limits for the Gypsum Board Drying Kiln are based on use of USEPA AP-42 (5th Edition 1/1995, updated 9/98), Sections 1.3 & 1.4, Fuel Oil Combustion & Natural Gas Combustion, emissions factors for external combustion boilers < 100 MMBtu/hr. NOx emissions limits while firing gas or oil are based on use of 1997 testing at the Portsmouth facility scaled up from 77.5% to 100% max load plus a 10% safety factor added. CO emissions limits while firing gas or oil are based on testing a similar gypsum board drying kiln at another National Gypsum facility plus a 10% safety factor added.

5. PM10 emissions limits for Raymond Mills #1 & #2 are based on an emission factor of 0.092 lb TSP/ton and maximum throughput rate of 30.0 tons/hr rather than using the AP-42 emission factor of 0.12 lb TSP/ton with the maximum throughput rate. In addition, Raymond Mill #2 is subject to the particulate matter emission limit of 0.05 grams per dry standard cubic meter and 7% opacity contained in 40 CFR 60 Subpart OOO, Sections 60.672(a)(1) and (2).

6. Old Hot Stucco System emissions limit is based on stack testing data from another facility of 0.020 grains/dry standard cubic foot and exhaust gas flow of 1252 dry standard cubic feet/minute.

7. New Hot Stucco System emissions limit is based on stack testing data from another facility of 0.020 grains/dry standard cubic foot and exhaust gas flow of 3210 dry standard cubic feet/minute.

8. Board Plant Silo and Feed System emissions limit is based on stack testing data from another facility of 0.020 grains/dry standard cubic foot and exhaust gas flow of 2887 dry standard cubic feet/minute.

9. Dry Additive Handling System emissions limit is based on stack testing data from another facility of 0.020 grains/dry standard cubic foot and exhaust gas flow of 2797 dry standard cubic feet/minute.

10. Board End Trim System emissions limit is based on stack testing data from another facility of 0.020 grains/dry standard cubic foot and exhaust gas flow of 3300 dry standard cubic feet/minute.

11. Riser Maker/Chopper System emissions limit is based on stack testing data from another facility of 0.020 grains/dry standard cubic foot and exhaust gas flow of 5450 dry standard cubic feet/minute.

12. Annual Emissions Limitations (tpy) - The Facility has the potential to emit the criteria pollutants NOx and SO2 at levels greater than the major source thresholds for these pollutants of 50 and 100 tpy, respectively. The annual emission limits in Condition IV.A are less than these thresholds and establish the Facility as a synthetic minor source of air pollution for NOx and SO2. The Facility does not have the potential to emit the criteria pollutants CO, PM10 or VOCs, or Hazardous Air Pollutants (HAPs, as defined in Section 112 of the 1990 Clean Air Act Amendments) at levels greater than the major source thresholds for these pollutants. Therefore, the Facility is a true minor source for CO, PM10, VOCs and HAPs.

13. The Rock Crusher is totally enclosed and does not have any gaseous emissions.

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Air Pollution Control Equipment at the Facility The facility operates particulate matter collection and control equipment on all devices listed in the operating permit with the exception of the Williams Rock Crusher, which is totally enclosed and has no open vents to the atmosphere. The only regulated toxic air pollutant emitted from the facility is gypsum, which is in the form of particulate matter and removed by the baghouses for each of the process devices listed in the Table. The Table below summarizes all of the air pollution control equipment at the facility by type of control equipment (baghouses), process it serves, and design criteria for the pollution control equipment.

Air Pollution Control Equipment Control Equipment Devices Vented to Control

Equipment Control Equipment Design Criteria

Rock Dryer Baghouse Rock Dryer FLEX KLEEN Model 100-WATC-324XL-III Serial# E 39008 Installed 9/1995 16,000 ACFM at 170 deg F 2.0 ft Diameter 85 ft AGL 99.9% RE, 5” H20 Pressure drop

Raymond Mill #1 Baghouse Raymond Mill #1, associated elevators, screws, and conveyors

FLEX KLEEN Model 84-WBC-96-IIIG Serial# 100094 Installed 1972 4,250 ACFM at 130 deg F 1.33 ft Diameter 83 ft AGL 99.5% RE, 3.0” H20 Pressure drop

Raymond Mill #2 Baghouse Raymond Mill #2, associated elevators, screws, and conveyors

FLEX KLEEN Model 84-WRBC96-IIIG Serial# 13-84-19749 Installed 5/1985 4,250 ACFM at 130 deg F 1.33 ft Diameter 52 ft AGL 99.5% RE, 3.0” H20 Pressure drop

Calcidyne Unit #2 Baghouse Calcidyne Unit #2 FLEX KLEEN Model 84-WRBC96-XL-IIIG Serial# 100544??? Installed 1999 4,100 ACFM at 340 deg F 1.08 ft Diameter 62 ft AGL 99.9% RE, 3.0” H20 Pressure drop

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Air Pollution Control Equipment Control Equipment Devices Vented to Control

Equipment Control Equipment Design Criteria

Calcidyne Unit #3 Baghouse Calcidyne Unit #3 FLEX KLEEN Model 84-WRBC96-XL-IIIG Serial# 100544??? Installed 1999 4,100 ACFM at 340 deg F 1.08 ft Diameter 62 ft AGL 99.9% RE, 3.0” H20 Pressure drop

Calcidyne Unit #4 Baghouse Calcidyne Unit #4 FLEX KLEEN Model 84-WRBC96-XL-IIIG Serial# 100717??? Installed 2001 4,100 ACFM at 340 deg F 1.08 ft Diameter 62 ft AGL 99.9% RE, 3.0” H20 Pressure drop

Calcidyne Unit #5 Baghouse Calcidyne Unit #5 FLEX KLEEN Model 84-WRBC96-XL-IIIG Serial# 100717??? Installed 2001 4,100 ACFM at 340 deg F 1.08 ft Diameter 62 ft AGL 99.9% RE, 3.0” H20 Pressure drop

Old Hot Stucco System Baghouse

Old Hot Stucco Bins and Conveying

FLEX KLEEN Model 84-WRBC48-III Serial# 13-84-19059 Installed 5/1985 1,492 ACFM at 140 deg F 0.83 ft Diameter 72 ft AGL 99.5% RE, 2.0-3.0” H20 Pressure drop

New Hot Stucco System Baghouse

New Hot Stucco Bins and Conveying

FLEX KLEEN Model 58-WRBC-144-II-XL Serial# 13-84-19767 Installed 5/1985 4,080 ACFM at 180 deg F 1.25 ft Diameter 13 ft AGL 99.5% RE, 3.0” H20 Pressure drop

Board Plant Silo & Feed System Baghouse

Board Plant Silo & Feed System

FLEX KLEEN Model 84-WRBC-96-II Serial# 13-84-19748 Installed 5/1985 3,440 ACFM at 140 deg F 1.08 ft Diameter 42.5 ft AGL 99.5% RE, 3.0” H20 Pressure drop

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Air Pollution Control Equipment Control Equipment Devices Vented to Control

Equipment Control Equipment Design Criteria

Dry Additive Handling System Baghouse

Dry Additive Handling System FLEX KLEEN Model 84-WRBC-96-IIG Serial# 13-84-19750 Installed 5/1985 3,000 ACFM at 80 deg F 1.08 ft Diameter 40.5 ft AGL 99.5% RE, 3.0” H20 Pressure drop

Board End Trim System Baghouse

Board End Trim System FLEX KLEEN Model 84-WRBC-96-II Serial# 13-84-19823??? Installed 10/1985 3,300 ACFM at 70 deg F 1.33 ft Diameter 30.0 ft AGL 99.5% RE, 5.0” H20 Pressure drop

Riser Maker/Chopper System Baghouse

Riser Maker/Chopper FLEX KLEEN Model 84-WRBC-96-II Serial# 13-84-19823??? Installed 10/1985 5,450 ACFM at 70 deg F 1.33 ft Diameter 30.0 ft AGL 99.5% RE, 4.0” H20 Pressure drop

Rule Applicability Env-A 603.01 – Permits Required

(a) – Devices listed in 607.01 require permits

Env-A 606.04, RSA 125-C:6, and RSA 125-C:11 – Air Dispersion Modeling Impact Analysis In order to comply with National Ambient Air Quality Standards, the facility must use No. 2 fuel oil with a sulfur content less than or equal to 0.30% sulfur by weight or use natural gas.

Env-A 700 – Emission-based Fees 704 – Emission-based fees

Env-A 800 – Testing and Monitoring Procedures 802 – Compliance Stack Testing for Stationary Sources\ 802.04 – Submit pre-test protocol 802.05 – Pre-test meeting 802.11 – Submission of test results within 60 days after completion of testing, this is the same as the 40 CFR 60 Subpart OOO, Section 60.676(f) requirement for submission of test results

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Env-A 900 – Recordkeeping and Reporting Requirements 902 – Availability of Records 902.01(a) - records retention = 5 yrs; 902.01(c) – maintain records in accordance with the applicable method used to demonstrate compliance with Env-A 1406 902.01(d) - all data submitted to ARD (emissions data & applicable emissions limitations) shall be made available to the public; 903 – General Recordkeeping for Process Devices and Combustion Devices; 903.02(a),(b) – General recordkeeping requirements for Process Operations. Records shall be kept regarding the total quantities of all raw materials utilized in each process which are required to calculate emissions, verify applicability and compliance with all emission limitations, or to verify production capacities and quantities. The Owner or Operator shall keep records of material throughput rates in tons or millions of square feet of gypsum wallboard as applicable for the Rock Dryer, Calcidynes #2-#5, Board Drying Kiln, Raymond Mills #1 & #2, Stucco Handling Systems (Old and New), Silo/Feed System, Dry Additive System, Board End Trim System, and Riser Maker and Chopper System. 903.03(a) – General recordkeeping requirements for Combustion Sources. Maintain monthly records or records for an alternative time period as approved by the Division in accordance with Env-A 912, of fuel characteristics and utilization in accordance with the following: For liquid fuels: Consumption, fuel type (i.e., No. 2 fuel oil), and weight percent sulfur of the fuel For gaseous fuels: Consumption, fuel type (i.e., natural gas), and sulfur content in grains per 100 cubic feet of gas 904 – General VOC Recordkeeping

NO - The facility does not reach the applicability threshold of ≥ 10tpy of VOCs.

905 – General NOx Recordkeeping Env-A 905.02 – For each combustion device, keep records of hours and days of operation per calendar month, number of weeks of operation, type and amount of fuel burned, heat input rate in MMBtu/hr, NOx emissions data (actual tons per calendar year and actual pounds per day for a high ozone season day during that calendar year), and the emissions factors and the origin of the emissions factors used to calculate the NOx emissions. 906 – Additional Recordkeeping Requirements

Keep track of consecutive 12 month totals of facility wide criteria pollutant emissions to demonstrate compliance with keeeping less than 100 tons SO2, 100 tons PM10, 100 tons CO, and 50 tons VOC and NOx per consecutive 12 month period.

907 – General Reporting Requirements; 907.01 (a) – submit annual emission report; due on or before April 15 of following year (907.01(c)) 907.01(b) – emissions report shall include: (1) - actual emissions and method used for calculations (2) – all information for process devices in accordance with 903.02(a) & (b).

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909 – NOx Emissions Statement Reporting Requirements 911 – Recordkeeping/Reporting for Permit Deviations 911.03(a) – investigate & take corrective action immediately upon discovery 911.03(b) – record the following:

• permit deviation • probable cause • date of occurance • duration • specific device • corrective or preventative measures taken

911.04 – Reporting Requirements: • (a) - No excess emissions but upset continues for > 9 consecutive days –

notify ARD of corrective action to be taken • (b) – deviation causes excess emissions – notify ARD w/in 24-hours of

discovery and submit written report w/in 10 days of discovery; • (c) – deviation caused by failure to comply with data availability

requirements of Env-A 800 – • notify ARD w/in 10 days of discovery of deviation; • report deviation as part of excess emissions reports submitted in

accordance w/Env-A 800. • (d) – written report shall include: • facility name; • facility address; • responsible official name; • facility phone #; • date(s) and time(s) of occurrence(s); • description of deviation; • specific device that contributed to the deviation; • probable cause of deviation; • corrective action taken to date; • preventative measures taken to prevent future occurrences; • date & time device returned to compliant operation; • type & quantity of excess emissions due to deviation; and • calculation or estimation used to quantify excess emissions.

Env-A 1204 – VOC RACT Requirements

Not applicable. The facility is below 10 tons of VOC emissions. Env-A 1211 – NOx RACT Requirements

Not applicable. The facility is opting out of NOx RACT by taking a federally enforceable emissions limit of less than 50 tons NOx per consecutive 12 month period via a fuel use restriction of less than 4,690,000 gallons of No. 2 fuel oil with a maximum sulfur content of 0.3% sulfur by weight. DES used an AP42 emission factor of 0.020 lb NOx/gal for distillate oil from Chapter 1.3, Table 1.3-1 for fuel oil combustion in small boilers (< 100 MMBTU/hr), which yielded a limit of 5,000,000 gallons per year. But in order to keep below 100 tons per year SO2 emissions DES had to check this fuel use

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limit with the maximum sulfur content of 0.3% sulfur by weight, an emission factor of (142 X 0.3)/1000 = 0.0426 lb SO2/gal was used, and the fuel limit was determined to be 4,690,000 gallons to stay below 50 tons of NOx and 100 tons of SO2 emissions per year.

Env-A 1400 – Regulated Toxic Air Pollutants

Yes. Gypsum is listed as an RTAP. The facility meets the AAL for gypsum without any operating restrictions. 1404.01(d) – Maintain a copy of the ambient air dispersion modeling analysis retained on site and available for inspection by the DES or EPA.

Env-A 1600 – Fuel Specifications

1605.01(a) – The sulfur content of natural gas shall contain no more than 15 grains of sulfur per 100 cubic feet of gas at standard temperature and pressure. 404.01 – Annual sulfur dioxide emissions from each Class B major source, shall have an average emission rate not to exceed 1.6 lb SO2/MMBtu input, equivalent to No. 6 fuel oil with 1.5 percent sulfur by weight, which is 75 percent of the baseline average emission rate for Class B major sources. RSA 125-C:6, RSA 125-C:11, and Env-A 606.04, Air Pollution Dispersion Modeling Impact Analysis: The maximum sulfur content allowable in No. 2 fuel oil used at the facility shall be less than or equal to 0.3 percent sulfur by weight.

Env-A 2000 – Fuel Burning Devices 2003.02 – Opacity less than 20% for the Rock Dryer, Calcidynes #2-#5, and the Gypsum Board Drying Kiln for any continuous 6-minute period. 2003.08 – TSP emission limit of 0.30 lb TSP/MMBtu heat input rate for the Rock Dryer, Calcidynes #2-#5, and the Gypsum Board Drying Kiln.

Env-A 2100 – Process, Manufacturing, and Service-Based Industries 2107 – Visible Emission Standard – Visible fugitive emissions or visible stack emissions shall not exceed an average of 20 percent opacity for any continuous 6-minute period, with the exception of the Raymond Mill #2, which is subject to opacity and particulate matter standards in 40 CFR 60 Subpart OOO. 2103.01 – Emissions Standards for Particulate Matter – All process devices at the facility with the exception of the exhaust of the baghouse on the Raymond Mill #2 are subject to the emissions standards specified for “New Devices” as listed in Table 2103-1.

40 CFR Part 60 (NSPS)

OOO – Standards of Performance for Nonmetallic Mineral Processing Plants Applies to Raymond Mill #2. Current Williams Crusher is exempt as it was an equal sized replacement of the Pennsylvania Crusher in 1999, but was required to do an initial notification. The Williams Crusher is included in the permit in that it is greater than the 25 ton/hr threshold in Env-A 607.01(l). 60.672(a)(1) – Particulate matter emission limit of 0.05 grams per dry standard cubic meter 60.672(a)(2) – Opacity limit of 7% opacity 60.675(a) and (b) – Test Methods and Procedures required during the performance test on Raymond Mill #2. Methods 5 or 17 for gaseous concentration and Method 9 for opacity. DES also included Methods 1 and 2 for stack volumetric flow measurement so the lb/hr

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emission rate can be determined during the stack test and compared against the lb/hr emission limit in the permit. 60.676(f) – Submission of test results. This is equivalent to Env-A 802.11 and DES has included Env-A 802.11 in the permit for submission of the test results. 60.676(h)(1) – Submission of notification of actual date of initial startup for Raymond Mill #2. 60.676(a) – Any time the facility replaces the Williams Rock Crusher with a unit of equal or smaller size it is required to submit a notification to DES and EPA containing the information in this Section.

UUU – Standards of Performance for Calciners and Dryers in Mineral Industries No – Applies to calciners and rock dryers which commence construction, modification, or reconstruction after April 23, 1986. Grinding equipment that also dries the process material used in the gypsum process is exempt from these requirements. The Rock Dryer was installed in 1965 and the four Calcidynes were installed in 1980. Hence, all of these emissions units are not subject to 40 CFR 60 Subpart UUU.

40 CFR Part 63 (MACT)

NO, source is not a major source of HAPs.