tfED srA/.
*	•	U.S. Environmental Protection Agency	19-P-0168
f AA \	Office of Inspector General	June 3 2019
* "jz7 s
"	At a Glance
Why We Did This Project
The Office of Inspector General
(OIG) conducted this audit to
determine whether the
U.S. Environmental Protection
Agency's (EPA's) existing
internal controls effectively
detect and prevent on-road
heavy-duty (HD) vehicle
emissions fraud. Effective
internal controls provide
reasonable—though not
absolute—assurance that the
potential for fraud is minimized.
In May 2018, we issued a
companion audit report that
focused on the EPA's light-duty
vehicle compliance program:
OIG Report No. 18-P-0181.
EPA Did Not Identify
Volkswagen Emissions
Cheating; Enhanced Controls
Now Provide Reasonable
Assurance of Fraud Detection.
This report addresses the
following:
•	Improving air quality.
•	Compliance with the law.
EPA Demonstrates Effective Controls for Its
On-Road Heavy-Duty Vehicle Compliance Program;
Further Improvements Could Be Made
Address inquiries to our public
affairs office at (202) 566-2391 or
OIG WEBCOMMENTS@epa.oia.
List of OIG reports.
What We Found
The EPA demonstrated that its current
internal controls are effective at detecting
and preventing noncompliance in the
on-road HD vehicle sector. Past instances
of noncompliance have resulted in excess
emissions of pollutants, which have significant and quantifiable negative impacts
on human health and the environment.
The EPA's HD vehicle compliance
program currently has controls to
effectively detect and prevent
noncompliance—a precursor to
potential fraud.
The on-road HD sector is the fastest growing transportation sector in the United
States based on fuel use and is a significant source of air pollution. Despite having
fewer on-road vehicles than the light-duty sector, the HD sector accounted for
35 percent more fine particulate matter emissions in calendar year 2014 than the
light-duty sector. Furthermore, the majority of emissions from the on-road HD
sector come from diesel engines, which—unlike gasoline engines—typically
operate more efficiently under conditions that produce higher emission levels of
regulated pollutants like nitrogen oxides and carbon monoxide. Manufacturers may
therefore be inclined to configure their diesel engines to operate at higher emission
levels. In the 1990s, the EPA discovered that multiple HD manufacturers illegally
used electronic engine controls to increase fuel efficiency at the expense of
pollution control. This discovery highlighted the importance of compliance
oversight and emission control in the HD sector, and the EPA made major
changes to the HD vehicle compliance program, including adding regulatory tests
to more accurately measure on-road emissions under real-world operating
conditions. These changes were fully implemented in 2007.
Although we found that the agency demonstrated that its existing internal controls
are effective, we identified specific risks to the EPA's goal of achieving public
health and environmental benefits through its HD vehicle compliance program. We
also identified areas where existing controls could be strengthened. These
improvements will help the EPA better address risks, assure compliance with
mobile source regulations, and protect human health and the environment.
Recommendations and Agency Planned Corrective Actions
We made eight recommendations to the Assistant Administrator for Air and
Radiation, including defining measures to assess program performance;
conducting a formal risk assessment that addresses specific risks; evaluating
whether specific programmatic or regulatory changes are necessary; assessing
whether the development of data analysis tools is feasible; evaluating
opportunities for targeted testing; tracking compliance issues in a standardized
manner; and developing procedures and criteria for referring compliance issues
to the Office of Enforcement and Compliance Assurance. The EPA agreed with
all recommendations. Two recommendations have been completed, and the
others are resolved with corrective actions pending.

-------