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Pacific Southwest, Region 9

Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations

FIP Rule Definitions

*Note: the following definitions are included based on their meaning to the Phoenix PM-10 FIP. In some cases, the definitions are simplified from those contained in the official FIP rule or have been added for clarity.

Average Daily Trips (ADT) - the average number of motor vehicles that travel on a given surface during a specified 24-hour time period. The ADT for an unpaved road can be determined using the Institute of Transportation Engineers Trip Generation Report (6th edition, 1997) or tube counts.

Chemical/Organic Stabilizer - Any non-toxic chemical or organic dust suppressant other than water which meets any specifications, criteria, or tests required by any federal, state, or local water agency and is not prohibited for use by the U.S. Environmental Protection Agency or any applicable law, rule or regulation.

Disturbed Surface Area - Any portion of land which has been physically moved, uncovered, destabilized, or otherwise modified from its undisturbed natural condition (including material dumping), thereby increasing the potential for fugitive dust emissions.

Dust Suppressants - Water, hygroscopic materials, solution of water and chemical surfactant, foam, or non-toxic chemical/ organic stabilizers not prohibited for use by the U.S. Environmental Protection Agency or any applicable law, rule or regulation, as a treatment material to reduce fugitive dust emissions.

EPA - United States Environmental Protection Agency, Region IX, 75 Hawthorne Street, San Francisco, California 94105. EPA's toll-free recorded assistance number: 1-800-300-2193.

FIP - Federal Implementation Plan

Flat Vegetation Test Method - A FIP rule test method for vacant lots that estimates the percent cover of flat, e.g. low-lying, horizontally oriented, vegetation on a given surface.

Fugitive Dust - particles lifted into the ambient air caused by man-made and natural activities such as the movement of soil, vehicles, equipment, blasting, and wind. This excludes particulate matter emitted directly from the exhaust of motor vehicles and other internal combustion engines, from portable brazing, soldering, or welding equipment, and from piledrivers.

Lot - A parcel of land identified on a final or parcel map recorded in the office of the Maricopa County recorder with a separate and distinct number or letter.

Low Use Unpaved Parking Lot - A lot on which vehicles are parked no more than thirty-five (35) days a year, excluding days on which 10 or fewer vehicles enter and park.

Maricopa County Environmental Services Division (MCESD) - 1001 North Central Avenue, Suite 201, Phoenix, AZ 85004. air Quality Division phone number: (602) 506-6010.

Motor Vehicle - A self-propelled vehicle for use on the public roads and highways of the State of Arizona and required to be registered under the Arizona State Uniform Motor Vehicle Act, including any non-motorized attachments, such as, but not limited to, trailers or other conveyances which are connected to or propelled by the actual motorized portion of the vehicle.

Non-Erodible Elements - objects larger than 1 centimeter in diameter that remain firmly in place even on windy days, such as rocks or hard-packed clumps of soil.

Off-Road Motor Vehicle - any wheeled vehicle which is used off paved roadways and includes but is not limited to the following: (1) any motor cycle or motor-driven cycle; (2) any motor vehicle commonly referred to as a sand buggy, dune buggy, or all terrain vehicle.

Owner/Operator - any person who owns, leases, operates, controls, maintains or supervises a fugitive dust source subject to the requirements of this rule.

Paving - Applying asphalt, recycled asphalt, concrete, or asphaltic concrete to a roadway surface.

Phoenix FIP Rule - A FIP rule covering unpaved roads, unpaved parking lots and vacant lots in the Phoenix PM-10 Nonattainment Area that was published in the Federal Register on August 3, 1998 (63 FR 41350). Amendments to the final rule were proposed on January 21, 1999 (64 FR 3263) that are reflected in this draft document.

Phoenix PM-10 Nonattainment Area Exiting EPA (disclaimer)
This area includes the Phoenix metropolitan area and surrounding cities within Maricopa County, excluding Apache Junction.

PM-10 - Particles 10 microns or less in size (smaller than the diameter of a human hair).

PM-10 Nonattainment Area - a geographic area that is not in compliance with federal health-based air quality standards for PM-10.

Reasonably Available Control Measures (RACM) - Techniques or methods used to prevent or reduce the emission and/or airborne transport of fugitive dust and dirt.

Rock Test Method - A FIP rule test method for vacant lots that measures the percent cover of non-erodible elements on a given surface.

Silt Content - mass of particles less than 74 microns in diameter.

Silt Content Test Method - A FIP rule test method for unpaved roads and unpaved parking lots that measures the silt content of routinely-traveled surfaces.

Silt Loading - Weight of silt per unit area.

Soil Test Method - A FIP rule test method for vacant lots that measures threshold friction velocity of disturbed soil.

Stabilized Surface - A surface which meets the FIP rule's criteria as being sufficiently stabilized. The FIP rule criteria for each source category are as follows:

Any unpaved road surface with a silt loading < 0.33 oz/ft2 or with a silt content that does not exceed six (6) percent as determined by the Silt Content Test Method;

Any unpaved parking lot surface with a silt loading < 0.33 oz/ft2 or with a silt content that does not exceed eight (8) percent as determined by the Silt Content Test Method;

Any vacant lot surface with:

  • a sufficient visible crust as determined by the Visible Crust Test Method;
  • a threshold friction velocity (TFV), corrected for non-erodible elements, of > 100 cm/second as determined by the Soil Test Method and Rock Test Method;
  • flat vegetation cover > 50 percent as determined by the Flat Vegetation Test Method;
  • standing vegetation cover > 30 percent as determined by the Standing Vegetation Test Method;
  • standing vegetation cover > 10 percent as determined by the Standing Vegetation Test Method, where threshold friction velocity, corrected for non-erodible elements, is > 43 cm/second as determined by the Soil Test Method and Rock Test Method.

Standing Vegetation Test Method - A FIP rule test method for vacant lots that measures the percent cover of standing, e.g. upright, vegetation on a given surface.

Threshold Friction Velocity (TFV) - The wind velocity necessary to initiate soil erosion.

Unpaved Parking Lot - A privately or publicly owned or operated area utilized for parking vehicles that is not paved and is not a Low Use Unpaved Parking Lot.

Unpaved Road - Any road, equipment path, or driveway that is not paved which is open to public access and owned/operated by any federal, state, county, municipal or other governmental or quasi-governmental agencies.

Urban or Suburban Open Area - An unsubdivided or undeveloped tract of land adjoining a residential, industrial or commercial area, located on public or private property.

Vacant Lot - A subdivided residential, industrial, institutional, governmental or commercial lot which contains no approved or permitted buildings or structures of a temporary or permanent nature.

Visible Crust Test Method - A FIP rule test method for vacant lots that tests the stability of a visible crust, which is a hardended or compact top surface layer.

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