Document ID: EPA-HQ-OAR-2012-0360-0106
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2015-03-18T04:00Z

MEMORANDUM

Date:		February 9, 2015

Subject:	Report of June 25, 2014 Site Visit to Veolia in Port Arthur, Texas

From:		Alden West, EC/R Incorporated 
		Lesley Stobert, EC/R Incorporated
		
To:		Paula Hirtz, EPA/OAQPS

This memorandum summarizes the visit to the Veolia facility in Port Arthur, Texas that was conducted on June 25, 2014. The purpose of this visit was to better understand the processes used in the Offsite Waste and Recovery Operations (OSWRO) industry, the controls in place to reduce hazardous air pollutants (HAP) emissions, and the characteristics of the emission points at this facility. This information will assist the EPA in the promulgation of amendments to the emission standards for the OSWRO industry. 

A background discussion of this project is provided, followed by an overview of the facility, a description of the off-site waste operations at the facility, and a summary of emission sources at the facility. The final section includes a summary of action items resulting from the meeting with Veolia. 

	The participants in the site visit included the following:
      Randa Coffey, Veolia
      Ron Constance, Veolia
      Daniel Duncan, Veolia
      Mitch Osborne, Veolia
      Paula Hirtz, U.S. EPA/OAQPS
      Lesley Stobert, EC/R Incorporated
      Alden West, EC/R Incorporated
      
      
BACKGROUND

Section 112(d) of the Clean Air Act requires the EPA to develop standards for each major source category listed under section 112(c). These technology-based standards are often referred to as maximum achievable control technology, or MACT, standards. The National Emissions Standards for Hazardous Air Pollutants (NESHAP) for Off-site Waste and Recovery Operations (OSWRO) were promulgated on July 1, 1996 (61 FR 34139) and codified at 40 CFR part 63, subpart DD. The Veolia facility in Port Arthur, TX is subject to subpart DD because it receives certain wastes from off-site locations for storage and treatment, recovery or disposal. 

Section 112 of the Clean Air Act contains provisions requiring the EPA to periodically revisit the technology-based standards. Specifically, section 112(d)(6) states that the EPA shall review these standards and revise them "as necessary (taking into account developments in practices, processes, and control technologies)" no less frequently than every eight years. The second stage in the review process focuses on reducing any remaining (i.e., "residual") risk according to CAA section 112(f). Section 112(f)(2) directs the EPA to assess the risk remaining (residual risk) after the application of MACT standards and promulgate additional standards as necessary to provide an ample margin of safety to protect public health, or to prevent, taking into consideration costs, energy, safety, and other relevant factors, an adverse environmental impact. On May 30, 2014, the EPA proposed amendments to the OSWRO MACT standards to address the results of the residual risk and technology review (RTR) conducted under the Clean Air Act.

A site visit of the Veolia facility was conducted to better understand the current processes and control technologies in the OSWRO industry before promulgation of final amendments to the OSWRO MACT standards. As part of the RTR process, the EPA is seeking additional information to improve the Agency's understanding of the OSWRO processes and emission points, to improve the data used in site-specific emission profiles and to better characterize the maximum risks to surrounding populations as a result of activities at OSWRO facilities. Further, the May 30, 2014 proposal includes new provisions that may change the way certain OSWRO sources are required to operate. This site visit was conducted to better understand the technical and operational implications of these changes based on current processes observed at the facility and discussions with facility personnel. 

PLANT SITE OVERVIEW
      
Veolia Environmental Services is a global company based in Paris with over $49 billion in revenue and is the largest environmental services company in the world. Veolia manages two incineration service locations in the United States, including the facility in Port Arthur, Texas. The Port Arthur facility is permitted under the Resources Conservation and Recovery Act (RCRA) as a hazardous waste Treatment Storage and Disposal Facility (TSDF). At this location, Veolia operates a rotary kiln and ancillary units for incineration of hazardous waste, two injection wells for waste disposal, and a regenerative thermal oxidizer (RTO) for control of HAP from offsite waste emission sources. The facility is one of three in the United States that is permitted to burn polychlorinated biphenyls (PCBs) commercially. While currently not permitted to treat F-listed dioxins, facility personnel indicated that they will soon be revising their permit to be able to incinerate those compounds.

PROCESS DESCRIPTION

As noted above, the processes of interest at this site are those regulated by the OSWRO MACT standards.  The description provided below is a summary developed from materials provided during the site visit and from notes taken based on discussions with Veolia personnel. 

Wastes accepted by Veolia include: aerosols; drum liquids, solids, and sludges; bulk liquids solids and sludges; lab packs; cylinders; and PCB capacitors. Drums and other smaller non-bulk containers are stored on racks in the container storage facility, which is a large open-air building. When a waste submitted for approval is received, Veolia first determines if it can be handled at the facility and if it is subject to subpart DD (OSWRO MACT). This determination is made based on a waste profile provided by the generator that includes a list of HAP constituents. Wastes containing Subpart DD constituents are inspected to determine if they are leaking. Leaking containers are resealed and reanalyzed for leaks; if the container is still leaking it will be stored under a hood to collect and control vapors before it is delivered directly to the incinerator. All waste streams are sampled unless they are exempted according to the facility's waste analysis plan (WAP). Containers can be burned individually by conveyance to the incinerator or they are conveyed to the mix pits for further processing. 

Veolia operates two pits where bulk and drum wastes are mixed based on BTU content. One pit contains low flash wastes and the other contains high flash wastes. High flash wastes ignite at temperatures greater than 140°F. The facility also operates two shredders and a blender/homogenizer. On the low flash side, waste from the pits and drum chute are shredded and blended under a nitrogen blanket, then pumped via a Putzmeister concrete pump to the incinerator, or waste is shredded and transferred directly to the incinerator on a conveyor. The doors to the mix pit area are open to the atmosphere; however, negative pressure is maintained in the building and emissions are vented through a particulate filter bag-house to the RTO. Emissions from the shredders are also vented to the RTO. 

Bulk solids are delivered to the facility in roll-off boxes that are sampled upon arrival in an enclosed building that is vented to a carbon adsorber. The facility is subject to the level 2 controls for containers (40 CFR §63.923), which require no detectable emissions (i.e., < 500 parts per million (ppm)) based on Method 21 monitoring. 

Bulk liquid wastes are delivered to Veolia in cargo tanks and/or trailers with ISO portable tanks. The facility operates direct injection lines where liquids are pumped from the truck directly to the incinerator. The direct injection lines are only used for certain types of liquid wastes than cannot be mixed with others. Liquids are also stored in tanks that range in size from 10,000 to 100,000 gallons. All storage tanks are equipped with fixed roofs and nitrogen blankets to suppress emissions. Vapors originating from normal pressure fluctuations in the tank are routed to the RTO. Tanks are also equipped with pressure relief valves (PRVs) that release vapors to the atmosphere to relieve emergency pressure buildup. PRVs are monitored every five days using Method 21. The facility has no instrumentation in place to determine the exact time or duration of a release or the amount of HAP that was released from a PRV. However, Veolia indicated that they have monitors that surround the tank to detect a release of hydrocarbons above a concentration threshold. 

Veolia operates a 60 foot long rotary kiln permitted under RCRA to treat/incinerate offsite wastes. Wastes are carefully selected for incineration based on BTU content and other factors to maintain optimal conditions in the kiln. An imbalance of BTU content in the waste can result in higher carbon monoxide levels at the exhaust stack. Combustion gases from the kiln are vented to a secondary combustion chamber, then to a rapid quench unit. The quench unit cools the incinerator exhaust from approximately 2000°F to 185°F in one second. The rapid cool down of exhaust gasses limits residence time in the formation temperature of dioxins and furans, which is 500°F to 800°F. Because dioxin and furan formation is prevented by the quench system, Veolia does not need to operate additional back-end pollution controls for these compounds. Combustion gases are vented from the quench system to the back-end pollution control systems,  an acid gas scrubber, a wet particle scrubber, and a wet electrostatic precipitator. The treated gas is then vented through a single stack equipped with a continuous emissions monitoring system (CEMS). 

Veolia operates injection wells in which scrubber blowdown from the incinerator, which contains metals and various salts, is injected into the ground for disposal. 

Veolia is currently testing a calciner pilot plant for recovery of nickel and molybdenum from offsite waste streams. 

EMISSION SOURCES
Emission sources at Veolia include containers, mix pits, tanks, fugitives, transfer systems, and control devices. Veolia operates an RTO as a control device for emissions from storage tanks, mix pits and shredders. 

Drums and other containers placed in the container storage facilities are sealed by a cover and closure device. The container storage facilities are not enclosed and hazardous vapors from leaking containers or sampling are emitted to the atmosphere. Subpart DD containers are monitored once for leaks when they are received. Leaking containers that cannot be resealed are placed under a hood to collect and control emissions before conveyance to the incinerator.

Bulk containers are sampled for leaks upon arrival in an enclosed building that is vented to a carbon adsorber. Bulk containers are required to have no detectable emissions (< 500 ppm) based on Method 21 monitoring. Secured tarps are installed on all bulk containers to suppress emissions.  

Emissions from mix pits can occur from storage, mixing, and shredding of drums and bulk solid wastes. The mix pit building is maintained at a negative pressure and emissions are vented to the RTO. 

Storage tank emissions can occur from the evaporation of liquid wastes placed in the tank. The storage tanks at Veolia are equipped with fixed roofs and nitrogen blankets to reduce evaporation of tank contents to the atmosphere. Tanks are also equipped with conservation vents that provide relief from fluctuations in pressure resulting from normal operating conditions such as filling/emptying and changes in atmospheric temperature. The conservation vents at Veolia are set to open when the internal tank pressure reaches 0.5 psi. Vapors released by the conservation vent are routed through a closed vent system to the RTO. All storage tanks are equipped with PRVs that will emit to the atmosphere if the tank internal pressure exceeds the device threshold setting for safe handling of liquid waste. The PRVs at Veolia are set to open at 2 psi, which is less than the pressure specified in the definition of a PRV in the 2014 OSWRO proposal (2.5 psi).

Veolia operates numerous valves, pump seals, flanges and other equipment components that could leak hazardous vapors to the atmosphere. Veolia complies with the leak detection and repair (LDAR) requirements of a new source review (NSR) permit that specifies a leak definition of 200 ppm for all components, which is more stringent than the LDAR requirements referenced by the OSWRO MACT standards. Veolia also has an agreement with the City of Port Arthur and EPA Region 6 based on an environmental justice review to do quarterly monitoring of vapors at the facility using an FLIR optical gas imaging (i.e., infrared) camera. According to Veolia, most refineries have their own optical gas imaging units; however, Veolia hires a subcontractor to conduct the monitoring.  

Transfer systems are a potential source of emissions at Veolia that are subject to the OSWRO MACT standards. Transfer systems operated at the facility include pumps and conveyers. Pumps are used to transport liquid waste from trucks at direct injection lines to the kiln, and homogenized waste from the blender to the kiln. Conveyors are used to transport containers and solid wastes to the shredders or kiln.

During the site visit, Veolia responded to a question on metals emissions from OSWRO sources. Metals are generally not a concern with offsite waste emission sources because they have very low or no vapor pressure at ambient temperature. There are no heating processes associated with OSWRO emission sources that would raise the vapor pressure of metals to the point where evaporation could occur. While mercury has a higher vapor pressure than other metals, it is usually combined with other compounds (e.g., phenyl mercuric acetate) from which it cannot easily evaporate. A facility that reclaims mercury in its pure form could potentially have higher mercury emissions; however, this operation is not conducted at Veolia. 

ACTION ITEMS

* EPA tentatively agreed to look into Veolia's concerns with the "in vapor service" designation of a PRD on a fixed roof storage tank equipped with a nitrogen blanket. Veolia contends that PRD on these types of tanks should be designated as "in liquid service".   
* EPA agreed to send Veolia a copy of the Federal Register notice for the proposed amendments to the OSWRO MACT standards.