June 10, 2015

Particulate Emissions That Fall to the Ground May Be Solid Waste?

What is the RCRA regulatory status of airborne particulate matter that subsequently falls to the ground? Many facilities generate air emissions from manufacturing operations that contain low concentrations of particulate matter which may fall onto their own or a neighbor’s property. In the past, such air emissions (including any entrained particulate) were generally considered to be subject to Clean Air Act regs only, since they were viewed as consisting of uncontained gaseous material. The RCRA statutory definition of solid waste includes “contained gaseous material,” but not uncontained gases. [RCRA Section 1004(27)]

But what about the non-gaseous particulate matter in these air emissions? If this material can be considered a point of generation of solid waste when it falls to the ground, then RCRA authority could be used to require cleanup of the contamination as a solid and potentially hazardous waste. This issue is the subject of two different lawsuits. Unfortunately, as discussed below, the two courts involved have come to different conclusions regarding the regulatory status under RCRA of airborne particulate matter that subsequently falls to the ground.

U.S. Court of Appeals for the Ninth Circuit

The Ninth Circuit Court found that diesel particulate matter from trains and other vehicles that is discharged into the air but that then falls onto nearby ground and water is not disposal of solid waste within the meaning of RCRA. [Center for Community Action and Environmental Justice et al. v. BNSF Railway Company et al.; Docket No. 12-56086; August 20, 2014]

The plaintiffs in this case alleged that the railroad companies “dispose” solid waste—specifically, diesel particulate matter—by allowing the waste to be “transported by wind and air currents onto the land and water near the rail yards.” The Ninth Circuit disagreed that this practice constituted “disposal” as that term is defined in the RCRA statute:

“The term ‘disposal’ means the discharge, deposit, injection, dumping, spilling, leaking, or placing of any solid waste or hazardous waste into or on any land or water so that such solid waste or hazardous waste or any constituent thereof may enter the environment or be emitted into the air or discharged into any waters, including ground waters.” [RCRA Section 1004(3)]

In examining RCRA’s definition of “disposal,” the court found that it 1) does not include the act of “emitting” solid waste into the air, and 2) includes only conduct that results in the placement of solid waste “into or on any land or water.” That placement, in turn, must be “so that such solid waste…. may enter the environment or be emitted into the air....” The court concluded “that ‘disposal’ occurs where the solid waste is first placed ‘into or on any land or water’ and is thereafter ‘emitted into the air.’” Thus, “‘disposal’ does not extend to emissions of solid waste directly into the air.” Because the diesel particulate matter is not first placed “into or on any land or water” but is first emitted into the air, disposal of solid waste under RCRA is not occurring.

District Court for the Southern District of Ohio

The second court involved in this issue has rendered two decisions, both of which found that airborne particulate emissions that reach the ground can be considered solid waste:

  1. The first case looked at two coal-burning electric generating units in Cheshire, Ohio. [Citizens Against Pollution v. Ohio Power Company; Docket No. C2-04-CV-371; July 13, 2006] Sulfur trioxide and sulfuric acid mist emitted from these units through two 830-ft stacks result in a blue plume, which is sometimes observed to touch the ground at some distance from the stacks. The court found that the “into or on any land” requirement in the definition of “disposal” is satisfied when the blue plumes touch the ground and that “the flue gas was discarded material resulting from industrial operations within the meaning of the RCRA...[and] that the flue gases were solid waste....”
  2. The second case involved perfluorooctanoic acid (C8) particulate matter emitted to the air via industrial stacks at a plastics manufacturing plant in southeast Ohio. [Little Hocking Water Association, Inc. v. E.I. du Pont de Nemours and Company; Docket No. 2:09-CV-1081; March 10, 2015] The manufacturer admitted that these emissions have subsequently been deposited on and contaminated a well field that is used to provide drinking water to local residents. However, the manufacturer contended that such emissions do not constitute disposal of solid waste under RCRA because they were an “uncontained” gaseous material and urged the court to follow the reasoning of the Ninth Circuit Court in the BNSF Railway case discussed above. Instead, the court found that “this type of soil and ground water contamination is precisely the type of harm RCRA aims to remediate in its definition of ‘disposal’.... Defendant’s aerial emissions of C8, which landed on the Plaintiff’s well field, and contaminated the soil and ground water, constitutes disposal of solid waste under RCRA....”


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This document addresses issues of a general nature related to the federal RCRA regulations. Persons evaluating specific circumstances dealing with the RCRA regulations should review state and local laws and regulations, which may be more stringent than federal requirements. In addition, the assistance of a qualified professional should be enlisted to address any site-specific circumstances.