INFORMATION RELATIVE TO 
THE DRAFT TITLE V OPERATING PERMIT
April 19, 2021

GENERAL FACILITY INFORMATION
Facility Name:  Roxul USA Inc. d/b/a ROCKWOOL 
Facility Address:  
4594 Cayce Road
Byhalia, MS 38611    
County: Marshall
SIC Code(s): 3296 – Mineral Wool
NAICS Code(s): 327993 – Mineral Wool Manufacturing  

APPLICATION SUMMARY 
Permit No.: 1780-00052
Permit Action:  Initial Issuance
Permit Folder: PER20150001
Application Receipt Date: 6/12/2015
Application Deemed Complete: 7/14/2015
CBI Submitted?: Yes	NSPS (Part 60): Subparts OOO and IIII
NESHAP (Part 61): N/A
NESHAP (Part 63): Subparts DDD, JJJJ, ZZZZ, and DDDDD
112(r) / RMP: N/A
Other: CAM Plans	

FACILITY DESCRIPTION
Roxul USA, Inc. d/b/a ROCKWOOL (ROCKWOOL), a subsidiary of Rockwool International, manufactures mineral wool insulation and associated products for consumer, commercial, and industrial applications. The facility is permitted to operate the following processes in the proposed Title V Operating Permit (TVOP):
•	AA-100 – Mineral Wool Line 1
•	AA-300 – Recycle Plant
•	AA-500 – Rockfon Line
•	AA-600 – Other Facility-Wide Operations and Activities
The facility was issued a Prevention of Significant Deterioration (PSD) Construction Permit on August 22, 2012, allowing for two phases of construction, with construction not to be suspended more than 18 months. The PSD Construction Permit was modified on February 25, 2014 and February 1, 2017 to address “as-built” changes. Phase I construction of Mineral Wool Line 1 and the Recycle Plant has been completed. However, Phase II, which consisted of construction of Mineral Wool Line 2 (AA-200), and construction of a Bitumen Line (AA-400) will not take place; therefore, the emission sources and permit requirements from the PSD Construction Permit for these lines will not be included in the TVOP. Also, other emissions equipment included in the PSD Construction Permit have not be constructed and will not be included in the TVOP, including the following: AA-108, AA-110, AA-117, AA-508, AA-600d, AA-600f, and AA-600g and other miscellaneous sources noted in the Title V application. The PSD Construction Permit is also being modified in coordination with the Title V issuance to address the as-built changes noted above.
A second PSD Construction Permit was issued on June 5, 2019 to address construction of a new Rockfon ceiling tile production line and specialty Rockfon products line (referred to as Off-Line Confectioning), as well as miscellaneous sources. An 18-month extension for beginning construction on this project was granted on December 29, 2020. Since construction has not begun on the emission sources addressed in this PSD Construction Permit, they will be incorporated at a later date, as addressed in Condition 4.3 of the TVOP. 
TITLE V SOURCE APPLICABILITY 
The facility’s potential-to-emit (PTE) exceeds the Title V major source threshold of 100 tons per year (tpy) for each of the following criteria air pollutants: Particulate Matter less than 10 microns (PM10), Particulate Matter less than 2.5 microns (PM2.5), volatile organic compounds (VOCs), sulfur dioxide (SO2), carbon monoxide (CO), nitrogen oxides (NOx), and reduced sulfur compounds (specifically, carbonyl sulfide). The facility’s potential-to-emit hazardous air pollutants (HAPs) exceeds the Title V major source thresholds of 25 tpy of total HAPs and 10 tpy for the following individual HAPs – carbonyl sulfide (COS), formaldehyde, methanol, fine mineral fibers, and phenol.

Facility-Wide Potential-to-Emit Summary1
Pollutant	PTE Emissions
(tons/yr)	
Particulate Matter (PM)2	119.20	
PM10	215.60	
PM2.5	106.47	
Sulfur Dioxide (SO2)	379.94	
Nitrogen Oxides (NOx)	208.81	
Carbon Monoxide (CO)	149.15	
Volatile Organic Compounds (VOC)	805.48	
Reduced Sulfur Compounds	322.37	
CO2e	181,103.49	
Lead	<0.01	
CFC/HCFC	0.00	
Total HAP 	825.01	
1 The PTE emissions reflect any emission limits or enforceable restrictions included in the proposed permit but do not include emissions from the proposed Rockfon lines addressed in the PSD permit issued in 2019. Emissions associated with the PSD permit issued in 2019 will not impact Title V applicability.
2 PM only includes the filterable portion; whereas, PM10 and PM2.5 include both filterable and condensable PM.

PREVENTION OF SIGNIFICANT DETERIORATION (PSD) APPLICABILITY
The facility is not one of the 28 categorical facilities listed in 40 CFR 52.21(b)(1)(i)(a); therefore, the PSD threshold for a major source is 250 tpy. The facility has the potential to emit more than 250 tpy of VOC and SO2; therefore, the facility is considered a major stationary source.  This permitting action will not change the current PSD status of the facility and does not involved any facility modifications that must be evaluated for PSD applicability.  Revisions to the PSD Construction Permit addressing “as built” changes will be incorporated in the TVOP as discussed further below.

FACILITY MODIFICATIONS AND/OR PERMIT CHANGES
This proposed permit does not include any proposed modifications or projects that have not otherwise be permitted through a PSD Construction Permit. In conjunction with issuance of the initial TVOP, the PSD Construction Permit issued for initial construction of the facility is being modified to reflect “as built” changes, which are also reflected in the proposed TVOP.  The Preliminary Determination for the revisions to the PSD Construction Permit discuss these changes in greater detail.  Following are a few other facility and/or regulatory changes addressed in the initial TVOP that are not based on PSD requirements.

•	Revisions to 40 CFR 63, Subpart DDD: Emission standards in Subpart DDD were revised in 2015 to address the residual risk and technology review (RTR) conducted by EPA. These revisions are reflected in the TVOP.
•	Revision to Curing Oven Controls: Due to higher than expected condensable PM in the curing oven exhaust, ROCKWOOL has added a water quench following the pretreatment filtration and afterburner. The water quench consists of atomized water injection to reduce PM emissions.

COMPLIANCE ASSURANCE MONITORING (CAM) APPLICABILITY
40 CFR Part 64 specifies the requirements for CAM.  The general applicability of this rule can be found in 40 CFR 64.2 and requires a Title V source to comply with the CAM requirements if all three of the following criteria are met for a pollutant-specific emission unit (PSEU):

1.	The unit is subject to an emission limitation or standard for a regulated air pollutant other than exemptions under 40 CFR 64.2(b)(1);
2.	The unit uses a control device to comply with the standard; and
3.	The unit has pre-control emissions exceeding Title V major source threshold.

CAM Applicability Table for Sources with Control Devices1
Emission Point ID	Control Device 
(not including inherent controls)	Applicable Limit/ Standard	Is standard exempt? (Yes/No)	Pre-Control > Major Threshold (Yes/No)	CAM Applies? (Yes/No)	Type of CAM PSEU
(Large/Other)2	
AA-101	Baghouse 	PM – 0.10 lb/ton
PM10 – 1.08 lb/ton
PM2.5 – 0.39 lb/ton	Only PM - 0.10 lb/ton (MACT DDD)	Yes	Yes	Large	
	Secondary combustion chamber	CO – 13.29 lb/hr
COS – 3.2 lb/ton	Only COS - 3.2 lb/ton (MACT DDD)
	Yes (CO)	Yes (CO)	Other	
	SNCR	NOx – 32.75 lb/hr	No	Yes	Yes	Large 	
	Fabric filter with dry sorbent injection	SO2 – 78.77 lb/hr
H2SO4 – 0.12 lb/ton
HF – 0.015 lb/ton
HCl – 0.012 lb/ton	Only HF and HCl (MACT DDD)
	Yes (SO2)	Yes (SO2)	Large	
AA-102	WESP	PM10 – 13.21 lb/hr
PM2.5 – 7.29 lb/hr	No	Yes	Yes	Other	
AA-103	Afterburner	Formaldehyde – 2.4 lb/ton
Methanol – 0.92 lb/ton
Phenol – 0.71 lb/ton	Yes (MACT DDD)	N/A	No	N/A	
	Pretreatment filtration/Water quench	PM10 – 6.25 lb/hr
PM2.5 – 5.18 lb/hr	No	No	No	N/A	
AA-105	Baghouse	PM/PM10 – 0.0044 gr/dscf
PM2.5 – 0.0022 gr/dscf	No	Yes	Yes	Other	
AA-107	Baghouse	PM/PM10 – 0.0044 gr/dscf
PM2.5 – 0.0022 gr/dscf	No	No	No	N/A	
AA-111	Fabric Filter	PM/PM10 – 0.02 tpy
PM2.5 – 0.01 tpy	No	No	No	N/A	
AA-112	Fabric filter	PM/PM10 – 0.31 tpy
PM2.5 – 0.16 tpy	No	No	No	N/A	
AA-113	Fabric filter	PM/PM10 – 1.24 tpy
PM2.5 – 0.62 tpy 	No	No	No	N/A	
AA-114	Bin vent filter	PM/PM10 – 0.39 tpy
PM2.5 – 0.19 tpy 	No	No	No	N/A	
AA-115	Bin vent filter	PM/PM10 – 0.39 tpy
PM2.5 – 0.19 tpy 	No	No	No	N/A	
AA-116	Bin vent filter	PM/PM10 – 0.24 tpy
PM2.5 – 0.12 tpy 	No	No	No	N/A	
AA-503	Baghouse	PM/PM10 – 0.34 lb/hr
PM2.5 – 0.17 lb/hr	No	Yes	Yes	Other	
AA-504	Particulate filters	PM10 – 0.08 lb/hr
PM2.5 – 0.06 lb/hr	No	No	No	N/A	
AA-506	Particulate filters	PM10 – 0.13 lb/hr
PM2.5 – 0.09 lb/hr	No	No	No	N/A	
AA-509	Particulate filters	PM10 – 0.88 lb/hr
PM2.5 – 0.66 lb/hr 	No	Yes	Yes	Other	
AA-600e	Vent filter	Use filter 	No	No	No 	N/A	
1 Green rows indicate emission points and related control devices subject to CAM.

CAM has been evaluated for all permitted emission sources. For those sources considered “Other” pollutant specific emission units, MDEQ requested and received CAM Plans though such plans are not due until the TVOP renewal. This will allow MDEQ to incorporate parametric monitoring appropriate for the unit. 

For Emission Point AA-101, NOx, SO2, and CO are controlled and have post-control emissions greater than 100 tpy, with exception of CO. The PSD permit addressing AA-101 requires use of a continuous emissions monitoring system (CEMS) to demonstrate continuous compliance consistent with the averaging period and units of the emission limits. The CEMS will be used to comply with CAM for these pollutants. For filterable PM controlled by the baghouse, MACT Subpart DDD requires a bag leak detection system calibrated using the recurring performance tests, which is considered presumptively acceptable monitoring. 

For Emission Point AA-102, the wet electrostatic precipitator (WESP) controls emissions from the Spinning Chamber and Cooling Section. The CAM Plan attached to the permit requires continuous monitoring of secondary voltage and secondary current with averaging performed daily. For Emission Point AA-105, the CAM plan requires an observation for any visible emissions on a daily basis. If visible emissions are observed, a Method 9 visible emissions evaluation must be conducted for 6 minutes. For Emission Point AA-503, the differential pressure across the baghouse is continuously monitored and a daily average calculated. For Emission Point AA-509, the filters for the Spray Paint Cabin are inspected daily, when the cabin is operated.  (Note that for sources of PM, CAM technically applies to PM10 and PM2.5, which are considered the Title V regulated pollutants.)

NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS (NESHAP) APPLICABILITY
ROCKWOOL is considered a major source of HAPs; therefore, only those NESHAP in Part 63 addressing major sources were evaluated for applicability. No NESHAP in Part 61 potentially applies to ROCKWOOL’s operations.

40 CFR Part 63, Subpart DDD – NESHAP for Mineral Wool Production
Subpart DDD applies to existing, new, and reconstructed cupolas and curing ovens at facilities producing mineral wool that are major sources of HAPs. Therefore, the Mineral Wool Line (AA-100) is subject to this subpart. The Melting Furnace (AA-101) is considered a new open-top cupola using slag as a raw material. Therefore, the Melting Furnace is subject to emission standards on PM, COS, HF, and HCl. To comply with Subpart DDD for the Melting Furnace, ROCKWOOL operates a bag leak detector and maintains the excess percent oxygen from the furnace at a minimum level set during performance testing. (As an aside, when the RTR rule revisions were promulgated, Subpart DDD included the option to maintain excess percent oxygen in lieu of monitoring the temperature of the incinerator. The revised rule failed to address any specific monitoring or recordkeeping provisions related to excess percent oxygen; therefore, DEQ included provisions consistent with averaging times in the rule and as proposed by ROCKWOOL.)

The RTR rule revisions regulate the combined collection/curing operations, which include the Spinning Chamber (part of AA-102) and the Curing Oven (AA-103). These are considered new combined vertical collection/curing operations subject to emission standards on formaldehyde, methanol, and phenol. ROCKWOOL does not operate any control devices under Subpart DDD for the Spinning Chamber but operates an afterburner on the Curing Oven, for which Subpart DDD requires continuous temperature monitoring. ROCKWOOL must combine the test results from the Spinning Chamber and Curing Oven to demonstrate compliance with the emission standards according to the Alternative Test Method approved by EPA. Subpart DDD also restricts the maximum free-formaldehyde content in the binder formulation to that used during the performance test. 

40 CFR Part 63, Subpart JJJJ – NESHAP for Paper or Other Web Coating
Subpart JJJJ applies to new and existing web coating lines at major sources of HAPs. The Fleece Application process (AA-119) and associated Curing Oven (AA-103) meet the definition of a web coating line when applying fleece because a continuous layer of liquid coating material (a binder or glue) is applied across the entire width of the web substrate which is flexible enough to be wound. Therefore, Fleece Application at Mineral Wool Line 1 is subject to Subpart JJJJ. ROCKWOOL complies with either an “as-purchased” or “as-applied” compliant coating materials option and does not use an add-on control device. Therefore, the Curing Ovens are not subject to any specific monitoring for the afterburner control device under Subpart JJJJ. Since cured mineral wool is not flexible enough to be wound as a roll, fleece application on cured mineral wool at the Rockfon Line is not subject to Subpart JJJJ. 

40 CFR Part 63, Subpart OOOO – NESHAP for Printing, Coating, and Dyeing of Fabrics and Other Textiles
Subpart OOOO applies to printing, coating, slashing, dyeing or finishing of fabric and other textiles. Per 40 CFR 63.4281(d)(1), Subpart OOOO specifically excludes any web coating operation that is part of the affected source of Subpart JJJJ (i.e., fleece application at the Mineral Wool Line). Also, Subpart OOOO applies to coating of a continuous textile substrate flexible enough to be wound or unwound. Since cured mineral wool cannot be wound or unwound, fleece application to cured mineral wool would not be subject to Subpart OOOO. Therefore, the fleece application processes at ROCKWOOL are not subject to Subpart OOOO.
	
40 CFR Part 63, Subpart ZZZZ – NESHAP for Stationary Reciprocating Internal Combustion Engines (RICE)
Subpart ZZZZ applies to new and existing stationary reciprocating internal engines at both area and major sources of HAPs. The only stationary engine at ROCKWOOL is the firewater pump engine (AA-600c) that is considered a new compression ignition (CI) stationary RICE. The engine is subject to Subpart ZZZZ but must comply with Subpart ZZZZ by meeting the requirements of 40 CFR Part 60, Subpart IIII for new compression ignition engines per 40 CFR 63.6590(c)(7). 

40 CFR Part 63, Subpart DDDDD – NESHAP for Industrial, Commercial, and Institutional Boilers and Process Heaters
Subpart DDDDD applies to both boilers and process heaters at major sources of HAPs. ROCKWOOL has numerous natural gas-fired sources providing heat and steam for their manufacturing processes. Each fuel burning unit was evaluated for applicability to Subpart DDDDD based on the definition of “boiler” and “process heater.”  Of the fuel burning units addressed in the Title V permit, only the two boilers (AA-600a and AA-600b) are subject to Subpart DDDDD. Based on the size (i.e., ≤ 5.0 MMBtu/hr) and subcategory (i.e., gas 1 unit), these boilers are subject to only work practice standards, including tune-ups every five years. 

With respect to the Mineral Wool Line, the preheat burners for the Melting Furnace (AA-101) and the Curing Oven circulation burners and afterburner (AA-103) provide direct heat to the process; therefore, they are not considered boilers or process heaters and are not subject to Subpart DDDDD. With respect to the Rockfon Line, the Drying Oven 1 (AA-504), High Oven A (AA-505), and Drying Ovens 2 & 3 (AA-506) all provide heat to the Rockfon process directly and are not subject to Subpart DDDDD. The three burners at the Rockfon Building 700 (AA-600h) and the miscellaneous Rockfon burners (part of AA-600i) provide heat indirectly but all provide “comfort heat or space heat” and, thus, are not considered process heaters as defined in Subpart DDDDD. The three Rockfon water heaters (part of AA-600i) meet the definition of “hot water heater” in Subpart DDDDD and are excluded from applicability under this subpart per 40 CFR 63.7491(d).

40 CFR Part 63, Subpart LLLLL – NESHAP for Asphalt Processing and Asphalt Roofing Manufacturing
The proposed Bitumen Line (AA-400) addressed in the PSD Construction Permit initially issued August 22, 2012, would have been subject to Subpart LLLLL. However, ROCKWOOL is not constructing this line and has requested it not be included in the Title V permit. 

NEW SOURCE PERFORMANCE STANDARDS (NSPS) APPLICABILITY
40 CFR Part 60, Subpart Dc – Standards of Performance for Small Industrial-Commercial-Institutional Steam Generating Units
Subpart Dc applies to steam generating units constructed, modified, or reconstructed after June 9, 1989 and having a maximum design heat input capacity of 10 MMBtu/hr to 100 MMBtu/hr.  The maximum heat input capacity of the steam generating units at ROCKWOOL (i.e., the boilers) do not equal or exceed 10 MMBtu/hr; therefore, the facility is not subject to Subpart Dc.

40 CFR Part 60, Subpart Kb – Standards of Performance for Volatile Organic Liquid Storage Vessels
Subpart Kb applies to storage vessels with a capacity greater than 75 m3 (19,813 gallons) used to store volatile organic liquids. ROCKWOOL does not have any storage vessels greater than this capacity; therefore, Subpart Kb does not apply to the facility. 

40 CFR Part 60, Subpart Y – Standards of Performance for Coal Preparation and Processing Plants
Subpart Y applies to coal preparation and processing plants that process more than 200 tons of coal per day. Coal preparation and processing plants include facilities that prepare coal using one or more of the following processes: breaking, crushing, screening, wet or dry cleaning, and thermal drying. ROCKWOOL received coal for use in the mineral wool process but does not prepare or process the coal at the facility using any of the noted processes. Therefore, ROCKWOOL is not subject to Subpart Y.

40 CFR Part 60, Subpart CC – Standards of Performance for Glass Manufacturing Plants
Subpart CC applies to each glass melting furnace constructed or modified after June 15, 1979. A glass melting furnace is specifically defined as a refractory vessel in which raw materials are charged, melted at high temperature, refined, and conditioned to produce molten glass. Since the facility does not product molten glass, or refine or condition melt, ROCKWOOL is not subject to Subpart CC.

40 CFR Part 60, Subpart LL – Standards of Performance for Metallic Mineral Processing Plants
Subpart LL applies to metallic mineral processing plants constructed or modified after August 24, 1982. Metallic mineral processing plants are defined as any combination of equipment producing metallic mineral concentrate from ore. ROCKWOOL produces mineral wool and does not produce a metallic mineral concentrate, as defined in Subpart LL; therefore, ROCKWOOL is not subject to Subpart LL.

40 CFR Part 60, Subpart UU – Standards of Performance for Asphalt Processing and Asphalt Roofing Manufacture
Subpart UU applies to each saturator and mineral handling and storage facility at asphalt roofing plants and each asphalt storage tanks and each blowing still at asphalt processing plants, petroleum refineries, and asphalt roofing plants. The proposed Bitumen Line would have produced an asphalt roofing product and been subject to Subpart UU. However, ROCKWOOL will no longer construct the Bitumen line; therefore, Subpart UU does not apply to the facility.

40 CFR Part 60, Subpart OOO – Standards of Performance for Nonmetallic Mineral Processing Plants
Subpart OOO applies to specified equipment in fixed or portable nonmetallic mineral processing plants constructed, modified, or reconstructed after August 31, 1983. ROCKWOOL operates equipment used to crush limestone and dolomite, which are both considered nonmetallic minerals; therefore, ROCKWOOL is subject to Subpart OOO. Specifically, the Conveyor Transfer Point (AA-111); the Charging Building Material Handling (AA-112), which houses sieves, crushers, conveyors, and bins; and the Filter Fines Receiving Silo (AA-116) are subject to Subpart OOO.  The Conveyor Transfer Point is subject to the specific PM emission standard of 0.014 gr/dscf. The Charging Building Material Handling is not equipped with any vents as defined in Subpart OOO; therefore, it is subject to the opacity standard of 7% per 40 CFR 60.672(e)(1). The remaining filter fines silo is considered an individual, enclosed storage bin under 40 CFR 60.672(f) and must meet the 7% opacity standard, but not the 0.014 gr/dscf PM standard. 

ROCKWOOL is permitted to operate a Lime Storage Silo (AA-120); however, this silo is not subject to Subpart OOO because this lime is not used in the crushing operation feeding the furnace but is used as the sorbent material to control emissions from the furnace. The Charging Building Vacuum System (AA-113) is used for housekeeping purposes and is not identified as an “affected facility” in Subpart OOO; therefore, the Charging Building Vacuum System is not subject to Subpart OOO.  The Recycle Plant (AA-300) and associated emission sources are not subject to Subpart OOO since they do not process “nonmetallic mineral,” as defined in Subpart OOO, but only formed mineral wool fibers.

40 CFR Part 60, Subpart PPP – Standard of Performance for Wool Fiberglass Insulation Manufacturing Plants
Subpart PPP applies to each rotary spin wool fiberglass insulation manufacturing line constructed, modified, or reconstructed after February 7, 1984. Wool fiberglass is defined as thermal insulation material composed of glass fibers and made from glass produced or melted at the same facility where the manufacturing line is located. ROCKWOOL’s mineral wool does not contain any glass fibers; therefore, ROCKWOOL is not subject to Subpart PPP.

40 CFR Part 60, Subpart VVV – Standards of Performance for Polymeric Coating of Supporting Substrates Facilities
Subpart VVV applies to each coating operation and onsite coating mix preparation equipment used to prepare coatings for the polymeric coating of supporting substrates, if the coating operation was constructed, modified, or reconstructed after April 30, 1987. According to 40 CFR 60.740(d)(2), Subpart VVV does not apply to coating mix preparation equipment or coating operations during those times they are used to prepare or apply waterborne coatings so long as the VOC content of the coating does not exceed 9 percent by weight of the volatile fraction. Although Fleece Application at Mineral Wool Line 1 and related coating mix preparation equipment would meet the definition of a “coating operation,” ROCKWOOL uses water-based coatings and glues with a VOC content well below 9 percent by weight of the volatile fraction. Therefore, ROCKWOOL is not subject to Subpart VVV.

40 CFR Part 60, Subpart IIII – Standards of Performance for Stationary Compression Ignition Internal Combustion Engines
Subpart IIII applies to owners and operators of stationary compression ignition (CI) internal combustion engines (ICE), including certified NFPA fire pump engines manufactured after July 1, 2006. ROCKWOOL has a permitted fire pump engine (AA-600c) that is a CI ICE combusting diesel fuel. This pump is subject to Subpart IIII and is considered an emergency CI ICE required to be certified to meet the emission standards in Table 4 for fire pump engines between 100 hp and 175 hp with a model year of 2010 and after. The pump engine must have a non-resettable hour meter to track hours of operation in both emergency and non-emergency situations. ROCKWOOL is not permitted to operate any other types of stationary engines.

SPECIFIC APPLICABLE REQUIREMENTS

Emission Point No.	Pollutant1	Draft Permit Emission Limits	Monitoring Requirements	
AA-000	Opacity 	≤ 20%	For Emission Points AA-101, AA-102, AA-103, AA-107, AA-111, AA-112, AA-503, AA-504, AA-506, and AA-509, conduct monthly visible emissions observations for three consecutive minutes. If visible emissions are observed, conduct a Method 9 visible emissions evaluation. Also, conduct Method 9 in conjunction with any required PM (Method 5 or 201A) stack testing. These sources have emissions of PM and use control devices to reduce PM emissions. Observations are not required for storage silos since these have bin vent filters which are considered inherent and only operate sporadically when material is transferred to them.	
	PM (filterable)	E=4.1*p0.67	Control devices must be operated at all times emissions are being vented. Monitoring related to PM sources is contained throughout the permit.  Controlled emissions from the Mineral Wool line are 24.58 lb/hr of PM (filterable). Controlled PM emissions from the Rockfon Line are 1.78 lb/hr.  Per the process weight equation, allowable filterable PM emissions for each Mineral Wool line are approximately 57 lb/hr and for the Rockfon Line are 10.4 lb/hr. Therefore, the current permit limits on PM and associated monitoring will ensure compliance with the process weight equation.	
AA-101, AA-102, AA-103 and AA-118, and AA-500	CO2e	158,060 tpy (AA-100 sources)
6,298 tpy (AA-500)	Calculate monthly and 12-month rolling total CO2e emissions using methods and factors from 40 CFR Part 98, fuel usage records, and other available data.	
AA-101	PM (filterable)
PM10 (f+c)
 PM2.5 (f+c)	0.10 lb/ton
1.08 lb/ton
0.39 lb/ton	MACT Subpart DDD and the CAM Plan require a continuous bag leak detector calibrated during the performance test. Conduct stack testing every two years for PM10/PM2.5 PSD limits and once every five years for the PM MACT standard. 

[2014 Stack Test: PM (filterable) = 0.00082 lb/ton, PM10 (f+c) = 0.11 lb/ton, PM2.5 (f+c) = 0.11 lb/ton, Opacity = 1.7%
2020 Stack Test: PM (filterable) = 0.02 lb/ton, PM10 (f+c) = 0.29 lb/ton, PM2.5 (f+c) = 0.29 lb/ton, Opacity = 14.0%]	
	SO2	78.77 lb/hr
500 ppmv	A CEMS for monitoring SO2 continuously is required. Both standards are expressed as a 30-day rolling average, since the emissions have been modeled and demonstrate compliance with the SO2 NAAQS.	
	H2SO4	0.12 lb/ton	Conduct stack testing every two years. 

[2014 Stack Test: H2SO4 = 0.14 lb/ton and 0.06 lb/ton (2015 follow-up) per Method 8; 
2019 Stack Test: H2SO4 = 0.33 lb/ton per Method 8;
2020 Stack Test: H2SO4 = 0.25 lb/ton per Method 8 and 0.002 lb/ton per CTM-013]	
	CO	13.29 lb/hr	A CEMS for monitoring CO continuously is required.	
	COS	3.2 lb/ton	MACT Subpart DDD requires continuous monitoring of oxygen and air input and fuel input to the furnace to maintain excess oxygen above the set point established during the performance test to ensure complete combustion. Performance testing is required every five years.	
	HF
HCl	0.015 lb/ton
0.012 lb/ton	MACT Subpart DDD requires performance testing every five years and continuous monitoring of oxygen and air input and fuel input to the furnace to maintain excess oxygen above the set point established during the performance test. 	
AA-102	PM10 (f+c)
PM2.5 (f+c)	13.21 lb/hr
7.29 lb/hr	Operate WESP according to the CAM Plan, which requires continuous monitoring of secondary voltage and secondary current in Zones 1 and 2 of the WESP. Conduct stack testing every two years. 

[2014 Stack Test: PM/PM10/PM2.5 (f+c) = 6.89 lb/hr, Opacity = 6.7 %
2019 Stack Test: PM/PM10 (f+c) = 8.66 lb/hr, PM2.5 (f+c) = 7.28 lb/hr, Opacity = 19.6 %]	
AA-103	PM10 (f+c)
PM2.5 (f+c)	6.25 lb/hr
5.18 lb/hr	Conduct Method 5 or Method 201A and Method 202 stack testing every two years. Testing shall be alternated such that the water quench system is operating during every other stack test conducted. Conduct monthly visible emissions observations. Operate afterburner according to MACT Subpart DDD. Perform monthly inspections of the pretreatment filtration. Operate the water quench system when manufacturing products with an LOIPUF above 3.5% to further reduce condensable PM, and monitor air pressure and water flow to the quench system to ensure adequate control.

[2014 Stack Test: PM (f+c) = 1.65 lb/hr, PM10 (f+c) = 1.62 lb/hr, PM2.5 (f+c) = 1.60 lb/hr, Opacity = 0%
2019 Stack Test: PM (f+c) = 29.19 lb/hr, PM10 (f+c) = 29.19 lb/hr, PM2.5 (f+c) = 29.17 lb/hr, Opacity = 0%]
2020 Re-Test: PM (f+c) = 8.39 lb/hr, PM10 (f+c) = 8.37 lb/hr, PM2.5 (f+c) = 8.35 lb/hr, Opacity = 0%
2020 Re-Test without Water Quench: PM (f+c) = 2.96 lb/hr, PM10 (f+c) = 2.96 lb/hr, PM2.5 (f+c) = 2.95 lb/hr, Opacity = 0%
2020 Re-Test with Water Quench: PM (f+c) = 1.00 lb/hr, PM10 (f+c) = 1.00 lb/hr, PM2.5 (f+c) = 0.91 lb/hr, Opacity = 15.3%]	
	NOx	12.13 lb/hr, 
0.078 lb/MMBtu	Conduct NOx stack testing every two years.  Install, operate, and maintain burners with a manufacturer’s guarantee at or below the limit. Perform annual inspection and tune-up of the burners. 

[2014 Stack Test: NOx = 3.34 lb/hr 
2015 Stack Test: NOx = 10.42 lb/hr @ lower afterburner temp.
2019 Stack Test: NOx = 2.88 lb/hr]	
	SO2, H2SO4	Good operating practices	Burners can only combust natural gas, containing minimal amounts of sulfur; therefore, no monitoring is needed.	
	CO, VOC	Use of afterburner	Compliance with the MACT Subpart DDD requirements will ensure the afterburner is operated in a manner that minimizes CO and VOC by ensuring complete combustion.	
AA-102*, AA-103
*Spinning Chamber only	Formaldehyde
Methanol
Phenol	2.4 lb/ton melt
0.92 lb/ton melt
0.71 lb/ton melt	Continuously monitor temperature in afterburner and maintain it above the minimum temperature established during the performance testing required every five years per MACT Subpart DDD.	
AA-105, AA-107	PM/PM10 
PM2.5
(filterable)	0.0044 gr/dscf
0.0022 gr/dscf	Conduct Method 5 and/or Method 201A stack testing every five years.  Conduct monthly visible emissions observations.
Per CAM Plan for AA-105, the permittee must conduct daily visible emissions observations to ensure the baghouse is operating appropriately.  
For AA-107, pressure drop is continuously measured across the baghouse and the baghouse is equipped with a warning alarm.

[AA-105 Stack Test (2014): PM = 0.00033 gr/dscf, PM10 = 0.00023 gr/dscf, PM2.5 = 0.0001 gr/dscf, Opacity = 0%
Stack Test (2019): PM = 0.0009 gr/dscf, PM10 = 0.0006 gr/dscf, PM2.5 = 0.0002 gr/dscf, Opacity = 0%]
[AA-107 Stack Test (2014): PM = 0.00121 gr/dscf, PM10 = 0.00121 gr/dscf, PM2.5 = 0.0006 gr/dscf, Opacity = 0%
Stack Test (2019): PM = 0.0004 gr/dscf, PM10 = 0.0004 gr/dscf, PM2.5 = 0.0002 gr/dscf, Opacity = 0%]	
AA-106
	PM/PM10/PM2.5
(filterable)	≤ 0.005% drift loss	Install mist eliminators with manufacturer’s guarantee meeting the 0.005% drift loss	
AA-109, AA-305	PM/PM10/PM2.5
(filterable)	Partial enclosure, good housekeeping	Construct and maintain partial enclosures for outdoor stockpiles. Develop and implement a Fugitive Dust Management Plan.	
AA-111	PM/PM10 
PM2.5
(filterable)	0.02 tpy
0.01 tpy	Comply with requirements of NSPS Subpart OOO, which requires quarterly visible emissions inspections, and conduct facility-wide monthly visible emissions observations.  The results of the stack test were below were below the emission factor used to calculate the emission limits (PM = 0.002 gr/dscf); therefore, no additional monitoring is required. 	
	PM (filterable)	0.014 gr/dscf	NSPS Subpart OOO requires an initial stack test and quarterly visible emissions inspections. 
[2014 Stack Test: PM = 0.0013 gr/dscf, Opacity = 0%]	
AA-112 	PM/PM10 
PM2.5
(filterable)	0.31 tpy
0.16 tpy	Conduct monthly visible emissions evaluations.  This source vents inside a building so there should be control provided by the building itself, in addition to the fabric filter.	
	Opacity 	≤ 7%	Comply with requirements of NSPS Subpart OOO, which requires visible emissions inspections every five years.  	
AA-113	PM/PM10 
PM2.5
(filterable)	1.24 tpy
0.62 tpy	The fabric filter is considered inherent to the process and the vacuum system is rarely used.  Controlled emissions are estimated to be 0.02 tpy of PM/PM10 and 0.01 tpy for PM2.5; therefore, no additional monitoring is required. 
[2015 Stack Test: PM/PM10 = 0.00027 gr/dscf and 0.00133 lb/hr (0.006 tpy), PM2.5 = 0.00014 gr/dscf and 0.00067 lb/hr (0.003 tpy), Opacity = 0%
2019 Stack Test: PM/PM10 = 0.013 tpy and PM2.5 = 0.006 tpy, Opacity = 0%]	
AA-114, AA-115	PM/PM10 
PM2.5
(filterable)	0.39 tpy
0.19 tpy	The bin vent filters on the coal silos are considered inherent; therefore, any loss of product which result in visible emissions will result in corrective action.	
AA-116	PM/PM10 
PM2.5
(filterable)	0.24 tpy
0.12 tpy	Comply with requirements of NSPS Subpart OOO, which requires quarterly visible emissions inspections.	
	Opacity 	≤ 7%		
AA-103, AA-119	Organic HAP	1.6 percent of mass of coating materials for each month or 8 percent of the coating solids applied each month	Comply with one of three options under MACT Subpart JJJJ each month: (1) as-purchased compliant coating materials, (2) as-applied compliant coating materials, or (3) total monthly organic HAP applied.	
AA-120	PM/PM10 
PM2.5
(filterable)	0.04 lb/hr
0.02 lb/hr	The bin vent filters on the lime silos are considered inherent; therefore, any loss of product which results in visible emissions will result in corrective action.	
AA-304	Hours of operation	12 hr/day, not to exceed 360 hr/yr	Monitor daily hours of operation and determine yearly hours of operation on a calendar year basis.	
AA-501, AA-502	PM10 (f+c)
PM2.5 (f+c)	0.02 lb/hr
0.01 lb/hr	Due to the minimal amount of emissions expected from these sources and difficult measuring those emissions given the small stack diameters, no monitoring is warranted. 	
	VOC	53 g/kg glue, not to exceed 7.48 tpy	Determine content of VOC in glue, as supplied by the manufacturer. Record monthly use of each type of glue and VOC content to determine the VOCs emitted each month and each 12-month rolling period.	
AA-503	PM/PM10 
PM2.5 
(filterable)	0.34 lb/hr
0.17 lb/hr	Conduct monthly visible emissions observations. CAM Plan requires continuous measurement of differential pressure and calculation of daily average to demonstrate efficient baghouse operation.
[December 2017 test results: PM = <0.087 lb/hr, PM10 = <0.065 lb/hr, PM2.5 = <0.044 lb/hr, Opacity = 0%]	
AA-504, AA-505, AA-506, AA-507, AA-509	VOC	80 g/liter coating, not to exceed 30.69 tpy	Determine content of VOC in coatings, as supplied by the manufacturer. Record monthly use of each type of coating and VOC content to determine the VOCs emitted each month and each 12-month rolling period.	
AA-504	PM10 (f+c)
PM2.5 (f+c)	0.08 lb/hr
0.06 lb/hr	Conduct monthly visible emissions observations and monthly inspections of the particulate filter.	
AA-505	PM10 (f+c)
PM2.5 (f+c)	0.12 lb/hr
0.09 lb/hr	No monitoring is proposed given the minimal uncontrolled emissions from combustion of natural gas.	
AA-506	PM10 (f+c)
PM2.5 (f+c)	0.13 lb/hr
0.09 lb/hr	Conduct monthly visible emissions observations and monthly inspections of the particulate filter.  	
AA-507	PM10 (f+c)
PM2.5 (f+c)	0.34 lb/hr
0.17 lb/hr	No monitoring is proposed given the minimal uncontrolled emissions.	
AA-504, AA-505, AA-506	SO2
NOx
CO	Natural gas only
Good combustion practices	Conduct an inspection and tune-up of each burner every five years, which is deemed sufficient given the small size of the burners and clean fuel combusted (i.e., natural gas).	
AA-509	PM10 (f+c)
PM2.5 (f+c)	0.88 lb/hr
0.66 lb/hr	CAM Plan requires daily inspections of the filters on days the spray paint cabin is operated. Also, monthly visible emissions observations are conducted.  	
AA-510	PM/PM10/PM2.5 (filterable)	Good housekeeping practices	Develop and implement a Fugitive Dust Management Plan to minimize fugitive emissions.	
AA-600a, AA-600b	NOx
PM (filterable)
PM10/PM2.5 (f+c)
CO
VOC
SO2	30 ppmvd NOx
Good combustion practices and
Natural gas only	Install low NOx burners with a manufacturer’s guarantee of 30 ppmvd NOx @ 3% O2. Combust natural gas to ensure emissions of other pollutants are minimal. Comply with MACT Subpart DDDDD, which requires tune-ups every five years.	
AA-600c	NMHC+NOx
PM
Fuel	4.0 g/kw-hr
0.30 g/kW-hr
Ultra-low sulfur diesel (ULSD)	Comply with the requirements of NSPS Subpart IIII by purchasing a certified engine and purchasing certified ULSD.	
AA-600e, AA-600j	PM/PM10/PM2.5 (filterable)	Use filter	Change filter according to manufacturer’s recommendations or ROCKWOOL preventive maintenance procedures	
AA-600h	NOx
PM (filterable) PM10/PM2.5 (f+c)
CO
VOC
SO2	70 ppmvd 
Natural gas only	Install low NOx burners with a manufacturer’s guarantee of 70 ppmvd NOx @ 3% O2. Conduct an inspection and tune-up of each burner every five years, which is deemed sufficient given the small size of the burners and clean fuel combusted (i.e., natural gas).	
AA-600i	NOx
PM (filterable), PM10/PM2.5 (f+c)
CO
VOC
SO2	Natural gas only and good combustion practices	These are very small (i.e., < 1 MMBtu/hr) comfort heaters and hot water heaters that combust natural gas.  Therefore, no monitoring is considered necessary. 	
AA-602	VOC	Good operating practices	Minimize spills and ensure containers, tanks, and drums are free of cracks, holes, and other defects and are closed when not adding or removing material from them.	
AA-603	PM/PM10/PM2.5 (filterable)	Dust Control Plan	Develop and implement a Fugitive Dust Management Plan to minimize fugitive emissions.	
1 “(f+c)” is filterable and condensable