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Mobile Agricultural Off-Road Diesel Engines (Code 372)

tractor disposal

The USDA Natural Resources Conservation Service (NRCS) is offering California growers and ranchers opportunities to apply new and innovative agricultural emission reduction practices and technologies that provide significant environmental benefits to our natural resources.

The Combustion System Improvement practice improves air quality by reducing oxides of nitrogen (NOx), volatile organic compounds (VOC), and particulate matter (PM10 and PM2.5) emissions from reciprocating internal combustion engines and related components.  This practice provides a payment for reducing diesel exhaust emissions by permanently removing from service diesel-powered in-use off-road mobile agricultural equipment and replace with new “like” equipment powered by emissions-certified nonroad diesel engines that meet or exceed federal, state, or local emission standards.  Real emission reductions are achieved when high-polluting diesel engines are replaced with new, cleaner emissions diesel engines earlier than through normal turnover.  Priority is on diesel engines operating within nationally designated air quality nonattainment areas in California.

Program Guidelines: 372 - Combustion System Improvement

EQIP Program Specifics

California growers and ranchers must meet eligibility requirements to qualify.

The in-use nonroad mobile diesel engine is:

  • Fully functional, in good operating condition, and has useful life remaining.
  • An uncontrolled (Tier 0) or emissions-certified Tier 1 or Tier 2 nonroad diesel engine rated at least 25 brake-horsepower (bhp) that self-propels off-road agricultural equipment.  Not included are stationary engines, auxiliary engines, portable or transportable engines mounted on trailers or skids, or engines that self-propel on-road trucks and vehicles.
  • Used routinely and exclusively in California by the participant for at least the past consecutive 24 months.
  • The old mobile agricultural off-road equipment is in-use and in good operating condition where:
  • The tires are in usable condition
  • The engine self-propels the equipment forwards and backwards
  • Buckets, blades, hydraulics, rollers, etc. are in working order
  • Undercarriage is structurally sound
  • Fuel tank is in usable condition with no leaks
  • No parts have been striped, and
  • The equipment has not been vandalized.

The new replacement mobile diesel engine is:

  • A nonroad diesel engine rated at least 25 bhp and within 125% of the old in-use engine horsepower rating.  Engine horsepower rating is based on the manufacturer’s advertised horsepower.
  • Equipped with a fully functional, non-resettable hour meter.  The hour meter must be fully-functional over the 10-year practice lifespan.
  • In new condition, where the diesel engine and equipment has not been previously sold or associated with any rental or lease agreement, has less than 250 operating hours recorded on a permanently mounted non-resettable hour meter, and covered under the manufacturer’s warranty.
  • Powers and self-propels the new mobile off-road equipment that serves the same function and performs the same work equivalent as the in-use unit (like-for-like).
  • Verified as meeting Tier 4 emission standards or current model-year California emission standards or equivalent. Emissions certification is by California Air Resources Board (ARB) Executive Order based on the applicable EPA Engine Family Name and nonroad engine model and code description. An EPA Certificate of Conformity is required if an ARB Executive Order is not available.

The participant must not purchase, make payments toward, or take possession of any new engine or equipment prior to receiving a fully executed contract.

  • The participant under contract must provide the appropriate NRCS field office with the applicable EPA Engine Family Name, engine model number or code descriptions, vehicle identification number, and engine serial number prior to purchasing the new engine and off-road agricultural equipment for emissions verification and NRCS concurrence.
  • To assure the emission reductions are real and permanent, the old engine and equipment must be destroyed and scrapped at a California scrap metal recycling facility. 
  • Recycling engine parts and drive-train components is not allowed.
  • The participant must provide the NRCS field office with the appropriate documents and photographs of engine destruction.  NRCS field office representatives may observe the destruction of the old in-use engine and equipment.
  • Please consult with your NRCS field office representative on where engines may be properly disposed and scrapped.
  • Projects must conform to the Combustion System Improvement Specifications.
  • A minimum two-year contract period is required. The participant initiates the project within one year. The practice lifespan is 10 years.
  • Participants must adhere to the Combustion System Improvement Operation and Maintenance requirements over the 10-year practice life.

Nonroad Diesel Engine Certification information is available online:

2007 San Joaquin Valley State Implementation Plan (SIP)

The NRCS supports voluntary measures for reducing air pollution emissions. There is no doubt that the San Joaquin Valley faces significant air quality challenges with achieving attainment of the National Ambient Air Quality Standards  (NAAQS). To address these challenges, the State of California Air Resources Board (ARB) adopted their “2007 State Strategy for California’s State Implementation Plan (SIP) for Federal PM2.5 and 8-Hour Ozone Standards” with a commitment to reduce diesel exhaust emissions from in-use mobile agricultural off-road equipment operating within the San Joaquin Valley through voluntary and regulatory measures (see Resolution 07-28, Attachment B, Pages 16 & 17 ).  The overall purpose is to accelerate natural turnover by installing the cleanest emissions-certified fleet as expeditiously as possible in order to achieve 5-10 tons per day of NOx emissions (an ozone precursor) by 2017.

Beginning in 2009, a partnership developed with agricultural stakeholders and representatives from the San Joaquin Valley Air Pollution Control District (SJVAPCD), ARB, US Environmental Protection Agency, and NRCS to help identify the mechanisms where voluntary incentive-based emission reductions could receive “credit” towards meeting the 2007 San Joaquin Valley SIP goals and objectives. Though this concept might delay compliance deadlines or adoption of new regulations, the overall benefits would better account for improvements to air quality, public health and welfare, and progress towards attaining the NAAQS.  

Applying voluntary incentive-based emission reductions toward such goals had never been tried before.  This direction led toward the SJVAPCD adoption of Rule 9610 in June 2013, which defines the administrative mechanisms where voluntary incentive-based emission reductions could become SIP creditable.  The ARB approved SJVAPCD Rule 9610 in October 2013 through their adoption of Section 2428, Title 13, of the California Code of Regulations. Together, these two rules ensure the emission reductions achieved through voluntary incentive programs implemented within the San Joaquin Valley become eligible for SIP credit in accordance with federal Clean Air Act requirements.

Keeping emission reductions voluntary does require periodic record keeping and reporting from San Joaquin Valley participants.  The information participants provide to the NRCS is used to quantify the emissions and ensure the on-going benefits continue over the practice 10-year lifespan. The NRCS will submit emission summary reports to the SJVAPCD, void of any information deemed as confidential, by reporting the emission reductions achieved within the San Joaquin Valley through EQIP for SIP consideration.

More information on this effort is available at the following websites:

For More Information

For more information about the Environmental Quality Incentives Program (EQIP), please contact your local USDA Service Center, listed in the government section of the phone book under U.S. Department of Agriculture. Information is also available on the Internet at

Updated: 12/17/2018