Fuel for Thought - ULSD Questions and Answers

Frequently Asked Questions on transition to Ultra Low Sulfur Diesel (ULSD) in Urban Alaska (on Federal Aid Highway Systems, (FAHS)) and EPA-approved small refiner provisions:


Mobile Sources:

  1. Are all areas of Alaska required to use ultra low sulfur (ULSD) diesel fuel?
  2. What are the fuel requirements for locomotive and marine (LM) diesel engines?

Stationary Compression Ignition Internal Combustion Engines:

  1. What are the fuel requirements for stationary compression ignition (CI) internal combustion engines (ICE) in urban/on Federal Aid Highway Systems (FAHS) in Alaska?

Small Refiner Provisions:

  1. Are there any importers/refiners in Alaska producing 500 ppm sulfur content diesel fuel?
  2. Who can the EPA-approved small refiner/importer distribute or otherwise sell 500 ppm sulfur content NRLM diesel fuel to?
  3. How should 500 ppm sulfur standard non-road, locomotive and marine (NRLM) diesel fuel be treated?
  4. Can 500 ppm sulfur content NRLM diesel fuel be used for highway?
  5. Can 500 ppm sulfur content NRLM diesel fuel be used in 2007 or later model diesel vehicles and non- road engines between June 1, 2010 and mid 2014?
  6. Can EPA-approved small refiner produce, import or otherwise distribute 500 ppm NRLM diesel fuel for heating use and electrical generation?

Mobile Sources:

1. Are all areas of Alaska required to use ultra low sulfur (ULSD) diesel fuel?

All areas of Alaska are required to use 15 parts per million (ppm) sulfur standard diesel fuel (ULSD) for all mobile diesel powered:

  • Highway/on-road vehicles (automobiles and trucks)
  • Nonroad/off-road equipment (graders, bulldozers and backhoes)
  • 2. What are the fuel requirements for locomotive and marine (LM) diesel engines?

    Locomotives and marine engines in urban Alaska are to transition to ultra low sulfur diesel by June 1, 2012.

    Stationary Compression Ignition Internal Combustion Engines:

    1. What are the fuel requirements for stationary compression ignition (CI) internal combustion engines (ICE) in urban/on Federal Aid Highway Systems (FAHS) in Alaska?

    Stationary diesel engines are regulated by a different set of EPA and State rules. Generally in urban Alaska:

  • Owners and operators of stationary CI engines with a displacement of less than 30 liters per cylinder subject to New Source Performance Standard (NSPS) must purchase fuel that meets requirements of 40 CFR 80.510(b) for nonroad diesel fuel, which requires maximum sulfur content of 15 ppm.
  • Owners and operators of stationary CI engines with a displacement of 30 liter per cylinder or greater must begin using 1,000 ppm sulfur content beginning June 1, 2012.
  • Small Refiner Provisions:

    1. Are there any importers/refiners in Alaska producing 500ppm sulfur content diesel fuel?

    There is one EPA-approved small refiner/importer that is allowed to produce 500ppm sulfur content non-road and locomotive (NRLM) diesel fuel until June 1, 2014.

    2. Who can the EPA-approved small refiner/importer distribute or otherwise sell 500ppm sulfur content NRLM diesel fuel to?

    EPA-approved small refiner/importers can distribute or otherwise sell 500ppm sulfur content NRLM diesel fuel to all appropriate legal end-users in Alaska, including:

  • Owners and operators of locomotive and marine engines in urban Alaska until June 1, 2012.
  • Owners and operators of stationary compression ignition (CI) internal combustion engines greater than or equal to 30 l/cyl in urban Alaska.
  • Owners and operators of pre-model 2014 stationary diesel engines in Rural Alaska.
  • A supplier that follows the compliance plan of the EPA-approved small refiner and distributes 500ppm standard sulfur to the appropriate legal end-user.
  • 3. How should 500ppm sulfur standard non-road, locomotive and marine (NRLM) diesel fuel be treated?

    All 500ppm sulfur standard NRLM diesel fuel must be properly labeled and segregated from other fuels.

    4. Can 500ppm sulfur content NRLM diesel fuel be used for highway?

    NRLM diesel fuel containing 500ppm sulfur CANNOT be used for highway.

    5. Can 500ppm sulfur content NRLM diesel fuel be used in 2007 or later model diesel vehicles and non- road engines between June 1, 2010 and mid 2014?

    NRLM diesel fuel containing 500ppm sulfur CANNOT be used in 2007 or later model diesel vehicles and non-road engines.

    6. Can EPA-approved small refiner produce, import or otherwise distribute 500 ppm NRLM diesel fuel for heating use and electrical generation?

    Until June 1, 2014, EPA-approved small refiners can distribute or otherwise sell 500 ppm sulfur content NRLM diesel fuel for heating and for use in unregulated engines to generate electricity.


    Contact Teri Buck at 907-269-7695, or email: teri.buck@alaska.gov if you have questions regarding ultra-low sulfur diesel and DEC's role.