Facility Contact with Mack Molding in Statesville, NC - Surface Coating of Plastic Parts for Business Machines (NSPS Subpart TTT)
Date
October 5, 2021
Subject
Data collection
Stakeholder
Mr. Frank Bumgarner
fbumgarner@mackmolding.com 
EPA in attendance
-
ERG in attendance
Bryan Lange
Mission:
The Clean Air Act requires the EPA to periodically review and revise its federal rules. We are asking for your help with this requirement for the NSPS Subpart TTT (Surface Coating of Plastic Parts for Business Machines). Mack Molding, out of Statesville NC was identified in an EPA database as subject to Subpart TTT. We collected your NC air permit and have confirmed this. 
We have prepared a short telephone survey for facilities that are subject to this rule. We hope to learn more about the impact of the 1988 rule, ways it might be improved for future facilities, and to look for innovation in the control of air pollution (e.g., new add-on control technologies, new work practices or operational procedure).  After the call we can share with you a copy of the minutes and discuss any necessary changes.
 Describe your business and surface coating process and approximately what fraction of your operation is used to coat plastic parts for business machines:
This Mack Molding Statesville location was constructed in the 1980s. As part of the original construction there were eight paint booths. Those booths pre-date the Subpart TTT regulations and are grandfathered. We had four booths subject to NSPS, but they have been completely removed because we were not using them. We kept them in the permit and left the exhaust fans/stacks and everything in the ceiling for the past 12-years and every 6-months we reported no Subpart TTT activity. 
As the result of some new business opportunities, specifically a contract with Gilbarco out of Greensboro who manufacture gas pump plastic housing, we installed two new booths which use two of those four existing exhaust fans. That Gilbarco job never started and those booths are currently idle. 
In the 1980 and 1990s we sprayed in those NSPS booths every day; there were restriction on photoreactive chemicals (e.g., xylene, toluene). Historically we used a RFI graphite material, but we no longer do that. 
In the 1980, everything was painted. Today, we produce 150 custom-colored materials that do not require painting (e.g., fine and heavy texture). 
Mr. Frank Bumgarner was willing to provide a tour and share any of his historical records. 

 Can you share with us an approximate annual surface coating throughput (approximately what fraction is used to coat plastic parts for business machines)?
We use approximately 6,500 gallons of paint every 6-months. I know that number because we are an ISO 14,000 company since 2007.  
Each product gets 2 or 3 mills thick of coating. 
We paint for approximately 25 different customers. We use a variety of finishes (e.g., water-based material, urethane material, smooth coat with/without texture). Our customers include E-Z-GO golf carts and Sensormatic (i.e., device installed at Target to make sure customers do not walk out with product). We have manufacture Sensormatic products for 20-years.
 We found your facility in a database indicating it is subject to NSPS subpart TTT (i.e., Surface Coating of Plastic Parts for Business Machines). Have you implemented any procedures or VOC control technologies to comply with that rule?
No. We considered an afterburner, but determined it was too costly. We are comfortably below our permit limit so VOC restrictions aren't something we worry about. 
Out NC air permit is the only thing that restricts operations for out grandfathered booths. We have a 100 ton per year VOC limit. We typically emit 65,000 pounds of VOC annually. 
 Have you made other accommodations to comply with Subpart TTT requirements and standards (e.g., VOC reporting requirements)? Are there business reasons for using paints with more than minimum VOC (e.g., because higher solvent contents are necessary for effective paint transfer for your product, or because the solvents preventing your coating from spoiling)?
Maintaining our ISO standard requires extensive record keeping. Specifically, we maintain an inventory of our hazardous waste (e.g., clean pots, waste paint) volume to track against our 15% target. A lot of our customers, like Volvo, that ship to Europe require the certification. We have 17-proceedures in place that are a result of that process. 
Customers specify the type of paint they want us to use. A customer may speck another paint and we will try to get it changed to Sherwin Williams; we have a good relationship with Sherwin Williams and know how to apply them and they can usually match the specifications. 


 Do you track either spray booths' transfer efficiency or VOC concentrations in booth exhaust?
Our grandfathered and NSPS booths are dimensionally identical, everything is enclosed (with glass) and each has a make-up air system. They have the same air flow (i.e., 200 cfm) and the exhaust for both are double filtered before it exits the stack. 
We do not track the transfer efficiency. We have experience painters. We track quality once the part is sprayed (e.g., gloss meters) and some companies require a certain film thickness. 
 If you were building a new plant in a different location to address a growing demand applying surface coating to plastic parts for business machines, how would it be different?
We would look at an afterburner and I'm sure that technology has improved. It would give us more leniency. 
We have optimized our production lines and we would duplicate what we have. We had a robot at one time, but it was removed because of our manufacturing part diversity, short runs (i.e., we may paint one part for 3 hours then another for 6 hours), and time to reset. 
 Do you have plans to expand your coating operation for plastic parts for business machines? 
If there was an increased need for surface coating, we could meet it. We have 24 molding presses and we run molding 24-hours a day 6-days a week (sometimes 7-days a week). Finishing shifts (which includes painting) run only 6-days, 12-hour per day. I will note that. 
It is Mack Molding policy that their operations never occupy over 80% of their available facility space. We were impacted by the pandemic, specifically due to supply of resins, paint, and materials. Some manufactured products we mold are not painted. 
 Do you have other industry contacts that are knowledgeable about the rule and might have useful input in our review?
Mack Molding in Inman SC does not have NSPS booths (together we make up Mack South) so there is no reason to call them.  
We do about $600,000 of business with Sherwin Williams. You might speak to our sales representative: Eric Kiever.

