While much has been made of U.S. EPA’s alleged scaling back of enforcement on various fronts and other policy changes, a wave of enforcement against mobile source engines appears ready to break on the heavy-duty diesel industry. U.S. EPA-Region 3 has initiated criminal prosecution for such a case, and this may be the beginning of a new wave of enforcement by the regions, similar to prior enforcement initiatives such as New Source Review and specific hazardous air pollutant cases against industry sectors.

U.S. EPA recently delegated the authority to prosecute mobile source violations from headquarters to the regions. This delegation is resulting in an increased number of enforcement actions against smaller entities not typically subject to U.S. EPA scrutiny, such as fleets of heavy duty engine operators and small/mid-sized diesel mechanic shops.

Regulation of Heavy Duty Diesel Engines

Mobile sources are regulated much differently than stationary sources under the Clean Air Act. For example, stationary sources receive permits for air emissions, but mobile sources are not required to obtain air emission permits. Instead, mobile sources are regulated through design and operational technology standards that apply when they are manufactured. Beginning in 2000, U.S. EPA established regulations specifically applicable to heavy-duty diesel engines. Under this program, U.S. EPA has required diesel engine manufacturers to install specific emission controls, such as filters to block particulate matter, and urea injection systems to control nitrogen oxide formation in these engines. These emissions controls have been the source of contention in the industry, as companies have observed that these systems create significant back pressure in exhaust systems, causing the engines to foul more quickly, increasing engine wear and lengthening service time. In addition, operators complain that the electronic control modules are unreliable, rendering vehicles inoperable and jeopardizing long-haul truckers’ livelihoods.

Recent Criminal Action

In a recent criminal case filed at the request of U.S. EPA in the Middle District of Pennsylvania (U.S. v. Rexer et al.), the agency brought a criminal action against a group of heavy-duty diesel truck operators, as well as the mechanic who serviced those vehicles and who allegedly disabled emission control systems on those vehicles in violation of Section 205 of the Clean Air Act. Notably, this action appears to be the first criminal case brought by one of U.S. EPA’s regions (specifically Region 3) following U.S. EPA Director of Air Enforcement Phil Brooks’ announcement in February 2018 that the agency intends to increase mobile source enforcement. Brooks cited anecdotal reports that up to 30% of used long-haul trucks show evidence of tampering with the emission control systems.

Enforcement Initiative Outlook

This enforcement initiative is worth monitoring for a number of reasons. U.S. EPA’s renewed focus on mobile source emissions appears to have been prompted by the now infamous Volkswagen case and has caused U.S. EPA to look more closely at the heavy-duty diesel industry. Traditionally, mobile source violations have been difficult to identify. Relevant vehicles are often located in areas where they are subject to an inspection and maintenance program and must be emissions tested, but annual testing is not required. In addition, long-haul trucks have historically been regulated more closely by the U.S. Department of Transportation (“DOT”) than U.S. EPA. Now the two agencies appear to be collaborating on these issues, which apparently led to the sharing of information underlying the Rexnercriminal action. In that case, the Pennsylvania DOT determined that the emission control systems on the relevant trucks were inoperative and notified U.S. EPA.

Whether other state agencies will follow Pennsylvania’s lead remains to be seen, but companies that lease or operate heavy-duty diesel transportation fleets should take note. Members of the industry frequently take issue with the U.S. EPA emission control requirements, arguing that the requirements put them at a competitive disadvantage and wear out the engines prematurely. Industry’s well known concerns with the stringent requirements may be fueling U.S. EPA’s assumption that a large number of used vehicles have been subject to tampering. In the past, it was difficult for U.S. EPA to detect these violations other than in rare cases where the agency directly sought information from diesel mechanics by requesting copies of their maintenance records to investigate whether the shop had been disabling emission controls. Now that the U.S. DOT, state DOTs and the U.S. EPA are collaborating more closely on these issues, U.S. EPA can let these other agencies do the investigative work that U.S. EPA traditionally has not done. Instead, U.S. EPA can monitor reports of vehicles U.S. DOT or state DOTs removed from the road because the emission control systems were disabled and pursue these matters through enforcement.

Recommendations for the Industry

Given the increase in enforcement in this area, owners and operators of transportation vehicles should consider adopting a formal written policy expressly prohibiting employees from disabling or altering any part of the emission control system on the company’s vehicles and implementing a compliance verification program to confirm that the emission control systems remain in operation, perhaps as part of the regularly scheduled engine maintenance program. These measures will serve key corporate compliance objectives, including (i) the prompt identification and remediation of potentially noncompliant vehicles before the government discovers the issue, (ii) providing documentation of good faith efforts to comply and refuting allegations that the company disregarded emission control requirements and profited from such noncompliance, and (iii) demonstrating a corporate commitment to sustainable and compliant operations.