Perhaps you have noticed a green and white label on the diesel fuel pump
at your service station. The label notes: ULTRA-LOW SULFUR HIGHWAY DIESEL
FUEL (15 ppm Sulfur Maximum) required for use in all model year 2007 and
later highway diesel vehicles and engines. This label is the manifestation
of the Environmental Protection Agency’s (EPA) Heavy-Duty Highway
Diesel Rule (a.k.a. 2007 Highway Rule). The rule, which was published in
January 2001, provided a lead-time of almost six years to allow diesel
engine manufacturers and refiners sufficient time to make the changes needed
to meet the new emission limits. Moreover, the rule is one of many such
rules issued pursuant to the Clean Air Act Amendments of 1990 aimed at
reducing emissions from all types of diesel engines.
Diesel engines emit nitrogen oxide (NOx) and particulate matter (PM),
or soot. NOx contributes to the formation of ground-level ozone or smog.
Smog and PM cause a number health problems related to breathing, and children,
the elderly and those with respiratory diseases are at greatest risk. EPA
estimates that the 2007 Highway Rule will reduce NOx emissions by 2.6 million
tons per year and PM emissions by 110,000 tons per year. Health benefits
include the avoidance of 8,300 cases of premature death, 5,500 cases of
chronic bronchitis and 17,600 cases of acute bronchitis in children each
The 2007 Highway Rule addressed the engine and the diesel fuel as a single
system. A key element of the emission-control scheme was the reduction
of the sulfur content of the fuel. Prior to 1993, there was no sulfur content
limit on highway diesel fuel. That year, EPA limited the sulfur content
to a maximum of 500 parts per million (ppm). This diesel fuel is known
as low-sulfur diesel. However, to achieve the emissions reductions called
for in the 2007 Highway Rule, a drastic reduction in sulfur content was
required. This is because sulfur interferes with the engine emission-control
technology required to control NOx and PM. The rule required a 97 percent
reduction in the sulfur content of fuel with a maximum 15 ppm of sulfur.
This fuel is called ultra-low sulfur diesel (ULSD).
There were two problems in meeting ULSD requirement. First, refiners
need time to modify their refineries to produce ULSD. Second, a program
was needed to assure that the ULSD was not contaminated with higher sulfur
content fuel in the diesel fuel distribution system. Certain diesel fuels,
such as home heating oil, can continue to have high sulfur content. The
diesel fuel distribution system consists of pipelines, barges, tank cars,
terminals and tank trucks that transport diesel from the refinery to the
service station. Most of this equipment is used to transport different
types of diesel; consequently, the risk for cross-contamination of ULSD
with higher sulfur content fuel exists. Too high a level of sulfur would
cause malfunction of the engine emission controls and excess emissions
of NOx and PM.
With input from refiners and diesel fuel distributors, EPA developed
a phased in approach to the ULSD requirements. EPA gave refiners nearly
six years – until June 1, 2006 – to convert their diesel production
to ULSD. Fuel terminals and transporters downstream of the refinery had
until September 1, 2006 to comply. To protect against cross-contamination,
a so-called “designate and track” program was established that
require product transfer documentation to track fuel. Fuel distributors
manage their equipment and product transfers to avoid contamination. Diesel
retail outlets could begin to offer ULSD as of October 15, 2006. The ULSD
costs an additional four to five cents per gallon. Because older model-year
diesel motor vehicles continue to run on low-sulfur diesel, some retailers
offer both types of diesel. However, pursuant to the rule, all highway
diesel fuel must be ULSD by December 1, 2010.
The availability of ULSD at retail outlets in the fall of 2006 was timed
to coincide with the introduction of model year 2007 cars, buses and trucks.
Engines in these 2007 models were designed to run on ULSD. So the right
fuel is delivered to the service station and right emission controls are
installed in the engine. The final step is for the consumer to properly
fuel the vehicle. That’s where the green and white label comes in.
The label is affixed to the pump to alert the consumer of the new fuel,
which is required for model year 2007. Improper fueling by the consumer
will defeat all of the upstream efforts by the refiners and distributors.
Improper fueling will also void the consumer’s warranty. Refiners,
distributors and retailers can be fined up to $32,500 per violation per
day for violating the ULSD regulations or for misrepresenting the sulfur
content of diesel fuel.
Charles E. Wagner, Jr., is an associate with
Blank Rome LLP in its Washington, DC, office. He is also Vice
Chair of the MSBA Environmental Law Section.