ATTACHMENT B
Imperial County Air Pollution Control District Rule 800

Imperial County Rule 800, Final Settlement, June 20, 2012

RULE 800 GENERAL REQUIREMENTS FOR CONTROL OF FINE PARTICULATE 

MATTER (PM-10) (Adopted 10/10/94; revised 11/25/96; revised 

11/08/2005; revised XX/XX/XX)

A. General Description

The purpose of this regulation is to reduce the amount of fine Particulate Matter

(PM-10) entrained in the ambient air as a result of emissions generated from 

anthropogenic (man-made) Fugitive Dust (PM-10) sources generated from within 

Imperial County by requiring actions to prevent, reduce, or mitigate PM-10 

emissions. The Rules contained within this Regulation have been developed 

pursuant to United States Environmental Protection Agency guidance for Serious 

PM10 Non Attainment Areas. 

B. Applicability

The requirements of this rule shall apply to any Active Operation, and/or 

man-made or man-caused condition or practice capable of generating Fugitive 

Dust (PM-10) as specified in this Regulation except those determined exempt as 

defined in Part E of this Rule. The definitions, exemptions, requirements, 

administrative requirements recordkeeping requirements, and test methods set 

forth in this rule are applicable to all the rules under Regulation VIII (Fugitive Dust 

Requirements) of the Rules and Regulations of the Imperial County Air Pollution 

Control District. 

C. Definitions

For the purpose of this Regulation, the following terms are defined:

C.1 ACTIVE OPERATION: Activities capable of generating Fugitive Dust (PM10), including but not limited to, Earthmoving Activities, Construction 

activities, Unpaved Roads, Track-Out/Carry-Out, Bulk Material storage 

and transport, Unpaved Haul/Access Roads.

C.2 AGGREGATE MATERIALS: Consists of sand, Gravel, quarried stone 

and/or rock fragments that are typically used in Construction. Aggregates 

may be natural, artificial or recycled.

C.3 ANEMOMETRS: Are devices used to measure wind speed and direction 

in accordance with manufacturer’s performance standards, maintenance 

and calibration criteria.

C.4 ANNUAL AVERAGE DAILY VEHICLE TRIPS: annual average 24-hour 

total of all vehicles counted on a road.

C.5 APCD: The Imperial County Air Pollution Control District.
Imperial County Air Pollution Control District Rule 800

Imperial County Rule 800, Final Settlement, June 20, 2012

C.6 APCO: The Imperial County Air Pollution Control Officer.

C.7 AVERAGE VEHICLE TRIPS PER DAY: Means the average number of 

vehicles that cross a given point surface during a specific 24-hour period 

as determined by the most recent Institute of Transportation Engineers trip 

generation manual, tube counts, or observations.

C.8 BLM: The Bureau of Land Management.

C.9 BP: The United States Border Patrol.

C.10 BULK MATERIAL: Earth, rock, Silt, sediment, sand, Gravel, soil, fill, 

Aggregate, dirt, mud, debris, and other organic and/or inorganic material 

consisting of or containing Particulate Matter with five percent or greater 

Silt content. For the purpose of this Regulation, the Silt content level is 

assumed to be 5 percent or greater, unless the Person responsible for the 

Active Operation conducts the applicable laboratory tests and 

demonstrate that the Silt content is less than 5 percent. Active Operations 

seeking to determine if the Silt content is less than five percent are 

required to conduct the laboratory analysis in accordance with ASTM 

method C-136-a (Standard Test Method for Sieve analysis of Fine and 

Coarse Aggregates), or other equivalent test methods approved by EPA, 

ARB, and the APCD.

C.11 CANAL BANK: A rise of land on either side of an irrigation canal.

C.12 CHEMICAL STABILIZATION/SUPPRESSION: A means of Fugitive Dust 

(PM-10) control implemented to mitigate PM-10 emissions by applying 

petroleum resins, asphaltic emulsions, acrylics, adhesives, or any other 

materials approved for use by the California Air Resources Board (CARB), 

U.S. Environmental Protection Agency (U.S. EPA) and/or the APCO.

C.13 CONSTRUCTION: Any on-site mechanical activities preparatory to or 

related to the building, alteration, rehabilitation, or demolition of an 

improvement on real property, including, but not limited to, land clearing, 

excavation related to construction, land leveling, grading, cut and fill 

grading, and the erection or demolition of any structure. As used in 

Regulation VIII, a construction site may encompass several contiguous 

parcels, or may encompass only a portion of one parcel, depending on the 

relationship of the property boundaries to the actual construction activities.

C.14 DESIGNATED REPRESENTATIVE: The agent for a Person. The 

Designated Representative shall be responsible for and have the full 

authority to implement BACM on behalf of the Person.
Imperial County Air Pollution Control District Rule 800

Imperial County Rule 800, Final Settlement, June 20, 2012

C.15 DISTURBED SURFACE AREA: An area in which naturally occurring soils, 

or soils or other materials placed thereon, have been physically moved, 

uncovered, destabilized, or otherwise modified by grading, land leveling, 

scraping, cut and fill activities, excavation, bush and timber clearing, or 

grubbing, and soils on which vehicle traffic and/or equipment operation 

has occurred. An area is considered to be disturbed until the activity that 

caused the disturbance has been completed, and the disturbed area 

meets the stabilized surface conditions specified in this rule.

C.16 DPR: The California Department of Parks and Recreation.

C.175 EARTHMOVING ACTIVITIES: The use of any equipment for an activity 

that may generate Fugitive Dust emissions, including, but not limited to, 

cutting and filling, grading, leveling, excavation, trenching, loading or 

unloading of Bulk Materials, demolishing, drilling, adding to or removing 

bulk of materials from open storage piles, weed abatement through 

disking, and back filling.

C.186 FUGITIVE DUST: The Particulate Matter entrained in the ambient air 

which is caused from man-made and natural activities such as, but not 

limited to, movement of soil, vehicles, equipment, blasting, and wind. This 

excludes Particulate Matter emitted directly in the exhaust of motor 

vehicles or other fuel combustion devices, from portable brazing, 

soldering, or welding equipment, pile drivers, and stack emissions from 

stationary sources.

C.197 GRAVEL: Gravel travelways shall have a three (3) inch minimum depth 

Stabilized Surface. The travelway shall have a relative compaction of not 

less than 95% as determined by Test Method No. California 216 of State 

of California, Business and Transportation Agency Department of 

Transportation, and conforming to the following grading:

3⁄4” Maximum

Sieve Designation Percent Passing

1” 100

3⁄4” 90-100

#4 35-60

#30 10-30

#200 2-9

Reference: California Department of Transportation Standard 

Specification Section 26/class II Aggregate Base

C.2018HAUL/ACCESS ROAD: Any on-site road used for commercial, industrial, 
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Imperial County Rule 800, Final Settlement, June 20, 2012

institutional, and/or governmental traffic.

C.219 HAUL TRUCK: Any fully or partially open-bodied licensed motor vehicle 

used for transporting Bulk Material for industrial or commercial purposes.

C.220IMPLEMENT OF HUSBANDRY: An unlicensed vehicle which is used 

exclusively in the conduct of Agricultural Operations. An Implement of 

Husbandry does not include a vehicle if its existing design is primarily for 

the transportation of persons or property on a highway, unless specifically 

designated as such by some other provision of the Vehicle Code of 

California.

C.231NON-RESIDENTIAL AREA: Any unpaved vehicle and equipment traffic 

area operated at any commercial, manufacturing or government sites.

C.242 MODIFIED PAVED ROAD: Any Paved Road that is widened or improved 

so as to increase traffic capacity. This term does not include road 

maintenance, repair, chip seal, pavement or roadbed rehabilitation that 

does not affect roadway geometrics, or surface overlay work.

C.253 OFF-FIELD AGRICULTURAL SOURCE: Any Agricultural Source or 

activity at an Agricultural Source that falls into one or more of the following 

categories:

C. 253.a Outdoor handling, storage and transport of Bulk Material;

C.253.b Paved Road;

C.253.c Unpaved Road; or

C.253.d Unpaved Traffic Area.

C.26 OFF-ROAD EVENT AND/OR COMPETITIONS: Means any of the 

following: any organized, sanctioned, or structured use, event or activity 

on public land in which two hundred and fifty (250) or more contestants 

compete and either or both of the following elements apply: (i) Participants 

register, enter, or complete an application for the event; (ii) A 

predetermined course or area is designated. 

C.274 OFF-ROAD HIGHWAY VEHICLE(OHV): Any nonstationary device, 

powered by an internal combustion engine or motor, used primarily off the 

highways to propel, move, or draw persons or property including any 

device propelled, moved, or drawn exclusively by human power, and used 

in, but not limited to, any of the following applications: marine vessels, 

construction/farm equipment, utility and lawn and garden equipment, offroad motorcycles, and off-highway vehicles. An off-highway vehicle is a 
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Imperial County Rule 800, Final Settlement, June 20, 2012

motorized vehicle when operating off a highway, including a two-wheel, 

three-wheel or four-wheel vehicle, motorcycle, four-wheel drive vehicle, 

dune buggy, amphibious vehicle, ground effects or air cushion vehicle and 

any other means of land transportation deriving motive power from a 

source other than muscle or wind. "Highway" means the entire width 

between the boundary lines of every way publicly maintained by the 

federal government, the department, a city, a town or a county if any part 

of the way is generally open to the use of the public for purposes of 

vehicular travel, excluding unpaved trails and paths specifically intended 

for recreational use.

C.285 ON-FIELD AGRICULTURAL SOURCE: Any Agricultural Source or activity 

at an Agricultural Source that is not an Off-Field Agricultural Source, 

including (but not limited to) the following:

C.285.a Activities conducted solely for the purpose of preparing land for 

the growing of crops or the raising of fowl or animals, such as 

brush or timber clearing, grubbing, scraping, ground excavation, 

land leveling, grading, turning under stalks, disking, or tilling;

C.285.b Drying or pre-cleaning of agricultural crop material on the field 

where it was harvested;

C.285.c Handling or storage of agricultural crop material that is baled, 

cubed, pelletized, or long-stemmed, on the field where it was 

harvested, and the handling of fowl or animal feed materials at 

sites where animals or fowl are raised;

C.285.d Disturbances of cultivated land as a result of fallowing, planting, 

fertilizing or harvesting.

C.296 OPEN AREA: Any of the following described in Subsection C.296.a 

through C.296.c of this rule. For the purpose of this rule, vacant portions 

of residential or commercial lots and contiguous parcels that are 

immediately adjacent to and owned and/or operated by the same 

individual or entity are considered one open area. An open area does not 

include any Unpaved Traffic Area as defined in this rule.

C.296.a An un-subdivided or undeveloped land whether or not it is

adjoining a developed (or partially developed) residential, 

industrial, institutional, governmental, or commercial area.

C.296.b A subdivided residential, industrial, institutional, governmental, 

or commercial lot, which contains no approved or permitted

building or structures of a temporary or permanent nature.
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C.296.c A partially developed residential, industrial, institutional, 

governmental, or commercial lot and contiguous lots under 

common ownership. 

C.3027PARTICULATE MATTER: Any material, except uncombined water, which 

exists in a finely divided form as a liquid or solid at 60 degrees F and one 

atmosphere pressure.

C.3128PAVED ROADS: An improved street, highway, alley, public way, that is 

covered by concrete, asphaltic concrete, or asphalt.

C.329 PERSON: Any individual, public or private corporation, partnership, 

association, firm, trust, estate, municipality, or any other legal entity 

whatsoever which is recognized by law as the subject of rights and duties, 

who is responsible for an Active Operation.

C.330 PM-10: Particulate Matter with an aerodynamic diameter smaller than or 

equal to a nominal 10 microns as measured by the applicable State and 

Federal reference test methods.

C.341 RECREATIONAL OFF-HIGHWAY VEHICLE (OHV) USE AREA: The use 

of motorized vehicles on public lands The entire area of a parcel of land, 

except for camping and approved buffer areas, that is managed for offhighway vehicle use through the development or designation of offhighway vehicle trails or areas.

C.352 RURAL: Areas not classified as urban constitute “rural.”

C.363 SILT: Any Aggregate Material with a particle size less than 75 

micrometers in diameter as measured by a No. 200 sieve as defined in 

ASTM D-2487 and as tested by ASTM-C-136 or other equivalent test 

methods approved by EPA, ARB, and the APCD.

C.374 STABILIZED SURFACE: Any disturbed surface area or open bulk storage 

pile that is resistant to wind blown Fugitive Dust emissions. A surface is 

considered to be stabilized if it meets at least one of the following 

conditions specified in this Section and as determined by the test methods 

specified in Appendix B, Section A, B and D-G tests of this rule:

C.374.a A visible crust; or

C.374.b A threshold friction velocity (TFV) for disturbed surface areas 

corrected for non-erodible elements of 100 centimeters per 

second or greater; or

C.374.c A flat vegetative cover of at least 50 percent that is attached or 
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rooted vegetation; or unattached vegetative debris lying on the 

surface with a predominant horizontal orientation that is not 

subject to movement by wind; or

C.374.d A standing vegetative cover of at least 30 percent that is 

attached or rooted vegetation with a predominant vertical 

orientation; or

C.374.e A standing vegetative cover that is attached or rooted vegetative 

with a predominant vertical orientation that is at least 10 percent 

and where the TFV is at least 43 centimeters per second when 

corrected for non-erodible elements; or

C. 374.f A surface that is greater than or equal to 10 percent of nonerodible elements such as rocks, stones, or hard-packed 

clumps of soil. 

C.385 STABILIZED UNPAVED ROAD: Any Unpaved Road or unpaved 

vehicle/equipment traffic area surface which meets the definition of 

Stabilized Surface as determined by the test method in Appendix B, 

Section C of this rule, and where VDE is limited to 20% opacity.

C.396 TACTICAL TRAINING: Training conducted by the U.S. Department of 

Defense, the U.S. military services, or its allies for combat, combat 

support, combat service support, tactical or relief operations. Examples 

include but are not limited to munitions training.

C.4037TEMPORARY UNPAVED ROAD: Any Unpaved Road surface which is 

created to support a temporary or periodic activity and the use of such 

road surface is limited to vehicle access for a period of not more than six 

months during any consecutive three-year period.

C.4138 THRESHOLD FRICTION VELOCITY (TFV): The corrected velocity 

necessary to initiate soil erosion as determined by the test method 

specified in Appendix B, Section D, of this rule. The lower TFV, the greater 

the propensity for fine particles to be lifted at relatively low wind speeds.

C.4239TRACK-OUT/CARRY-OUT: Any and all Bulk Materials that adhere to and 

agglomerate on the exterior surfaces of motor vehicles and/or equipment 

(including tires) that may then fall onto the pavement.

C.430 TRACK-OUT PREVENTION DEVICE: A Gravel pad, grizzly, wheel wash 

system, or a paved area, located at the point of intersection of an unpaved 

area and a Paved Road that prevents or controls Track-Out.

C.441 UNPAVED ROADS: Streets, alley ways, or roadways that are not covered 
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by one of the following: concrete, asphaltic concrete, asphalt, or other 

similar materials specified by the U.S.EPA, CARB and/or the APCO.

C.452 UNPAVED TRAFFIC AREA: Any nonresidential area that is:

C.452.a Not covered by asphalt, recycled asphalt, asphaltic concrete, 

concrete, or concrete pavement, and

C.452.b Used for fueling and servicing; shipping, receiving and transfer; 

or parking or storing equipment, haul trucks, vehicles, and any 

conveyances.

C.463 URBAN AREA: An area within an incorporated city boundary or within 

unincorporated areas completely surrounded by an incorporated city.

C.474 VDE: Visible dust emissions. Dust emissions that are visible to an 

observer.

C.485 VMT: Vehicle miles traveled.

C.496 WIND GUST: Is the maximum instantaneous wind speed as measured by 

an anemometer.

D. Compliance Schedule

D.1 Existing sources subject to this Regulation shall comply with its 

requirements no later than 90 days after its adoption date.

D.2 New sources subject to this Regulation shall comply with its requirements 

prior to initiation of activity.

D.3 The BLM and BP and any person (including BLM and DPR) who owns or 

operates a Recreational OHV Use Area on public lands shall each comply 

with the following compliance schedule:

D.3.a Submit a draft dust control plan addressing all applicable 

portions of this Regulation including section F.5 and F.7 within 

three (3) months of the adoption date of this rule, to which the 

APCO shall respond within 60 days;

D.3.b Submit a final dust control plan addressing all APCO 

comments within two (2) months after receiving APCO’s 

comments, which the APCO shall transmit to CARB and U.S. 

EPA for 45-day review and comment;

D.3.c If comments received from CARB or EPA, submit to them and 
Imperial County Air Pollution Control District Rule 800

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APCO a revised final dust control plan addressing all 

comments within two (2) months after receiving comments.

D.3.dc Implement all final dust control plan elements within six (6) 

months of submittal; and

D.3.ed Submit an updated dust control plan every two calendar years 

by the procedures described in D.3.a to D.3.dc. The updated 

plans shall be transmitted to the District no later than 90 days 

after the end of the calendar year and, in addition to information 

required of the initial plan, shall include a summary of actions 

taken to prevent or mitigate PM10 emissions during the 

previous two years.

E. Exemptions 

The following activities are exempt from provisions of this Regulation:

E.1 Actions required by the Federal or State Endangered Species Act or any 

order issued by a court or governmental agency.

E.2 Off-Field Agricultural Sources necessary to minimize or respond to 

adverse effects on agricultural crops caused during freezing temperatures 

as declared by the National Weather Service.

E.3 Emergency maintenance of flood control channels and water spreading 

basins.

E.4 Any emergency operation activities performed to ensure public health and 

safety. Emergency activities lasting more than 30 days shall be subject to 

this Regulation, except where compliance would limit the effectiveness of 

the emergency activity performed to ensure public health and safety.

E.5 Blasting operations permitted by the California Division of Industrial 

Safety. Other activities performed in conjunction with blasting are not 

exempt from complying with the provisions of this rule.

E.6 The Recreational Use of public lands covered by the most recent BLM 

dust control plan that complies with Rule 800, including but not limited to 

Off-Road Vehicles, all-terrain vehicles, trucks, cars, motorcycles, 

motorbikes or motorbuggies.

E.67 The following military training activities conducted by the Department of 

Defense: (1) military Tactical Training, (2) maintenance, repair, and 

removal of targets and munitions associated with military Tactical Training, 

(3) open areas on active military ranges, including but not limited to 
Imperial County Air Pollution Control District Rule 800

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designated impact areas, landing zones, and bivouac areas. However, 

unpaved roads, staging areas, parking lots, and Oother activities 

performed in conjunction with military Tactical Training are not exempt 

from complying with the provisions of this rule Regulation, as applicable.

F. General Requirements

F.1 Materials used for Chemical Stabilization of soils, including petroleum 

resins, asphaltic emulsions, acrylics, and adhesives shall not violate State 

Water Quality Control Board standards for use as a soil stabilizer. 

Materials accepted by the California Air Resources Board (ARB) and the 

United States Environmental Protection Agency (EPA), and which meet 

State water quality standards, shall be considered acceptable to the 

ICAPCD.

F.2 Any material prohibited for use as dust Suppressant by EPA, the ARB, or 

other applicable law, rule, or regulation is also prohibited under Regulation 

VIII.

F.3 Use of hygroscopic materials may be prohibited by the APCD in areas 

lacking sufficient atmospheric moisture of soil for such materials to 

effectively reduce Fugitive Dust emissions. The atmospheric moisture of 

soil is considered to be sufficient if it meets the application specifications 

of the hygroscopic product manufacturer. Use of such materials may be 

approved in conjunction with sufficient wetting of the controlled area.

F.4 Any use of dust Suppressants or gravel pads, and paving materials such 

as asphalt or concrete for paving, shall comply with other applicable 

District Rules.

F.5 Recreational OHV Use Area on Public lands Dust Control Plan Bureau of 

Land Management (BLM) Requirements

The BLM, DPR, or any other owner or operator of a Recreational OHV 

Use Area on public lands shall prepare a dust control plan to minimize 

PM-10 emissions. for sources under the control of BLM. The dust control 

plan shall include at a minimum the following:

F.5.a A stipulation that all new authorizations for point and area 

stationary emission sources obtain all necessary permits and 

satisfy all applicable SIP provisions, including Regulation VIII 

specific control measures;

F.5.b A summary of: 

F.5.b.1 Tthe total miles of BLM roads in the Recreational 
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Imperial County Rule 800, Final Settlement, June 20, 2012

OHV Use Area on public lands that are paved, paved 

with unpaved shoulders, and unpaved roads with 50 

or more average vehicle trips per day, including 

length and level of usage of each such road; the 

priority for control of road segments based on annual 

and episodic (e.g. event) usage; the plans for control 

of PM-10 emissions from these roads; 

F.5.b.2 Tthe location and extent (e.g. acreage and where 

feasible, estimate of number of vehicles) of open 

areas disturbed by legal and illegal Recreational Use,

including maps such as those required by California 

Public Resources Code (PRC) section 5090.34; the 

priority for control of these open areas based on 

annual and episodic (e.g. event) usage; the plans for 

control of PM-10 emissions from these areas;

F.5.c BLM must demonstrate in its dust control plan that Unpaved 

Roads, parking, and Open Areas are controlled pursuant to the 

applicability and requirements of Rules 804 and 805 except 

where measures are demonstrated by BLM to be prohibited by 

federal or state laws, regulations, or approved plans concerning 

wilderness preservation and species management and 

recovery.

Unpaved Roads and Unpaved Vehicle/Equipment Traffic Area. 

The dust control plan shall be implemented on all days that 

traffic exceeds, or is expected to exceed, the number of average 

daily vehicle trips per day as specified in sections F.5.c.1 and 

F.5.c.2 of this rule, except where measures are demonstrated 

by owner/operator to be prohibited by federal or state laws, 

regulations, or approved plans concerning wilderness 

preservation and species management and recovery. 

F.5.c.1 On each day of an Off-Road Event and/or 

Competition that 50 average vehicle daily trips per day will occur 

on an unpaved road segment, the owner/operator shall limit 

VDE to 20% opacity and comply with the requirements of a 

stabilized unpaved road by application and/or reapplication/maintenance of at least one of the following control 

measures:

F.5.c.1.1 Watering;

F.5.c.1.2 Uniform layer of washed gravel;

F.5.c.1.3 Paving;

F.5.c.1.4 Restrict access;

F.5.c.1.5 Restrict speed limit at or below 15 mph;
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F.5.c.1.6 Chemical/organic dust suppressants;

F.5.c.1.7 Roadmix;

F.5.c.1.8 Any other method(s) that can be demonstrated that 

effectively limits VDE to 20% opacity and meets the 

conditions of a stabilized unpaved road.

F.5.c.2 On each day of an Off-Road Event and/or 

Competition that 50 average vehicle daily trips per day will occur 

on an unpaved surface area dedicated to any vehicle parking 

and traffic activity, the owner/operator shall limit VDE to 20% 

opacity and comply with the requirements of a stabilized 

unpaved road by application and/or re-application/maintenance 

of at least one of the following control measures:

F.5.c.2.1 Watering;

F.5.c.2.2 Uniform layer of washed gravel;

F.5.c.2.3 Paving;

F.5.c.2.4 Restricted access below the limit;

F.5.c.2.5 Restrict speed limit at or below 15 mph;

F.5.c.2.6 Chemical/organic dust suppressants;

F.5.c.2.7 Roadmix;

F.5.c.2.8 Any other method(s) that can be demonstrated that 

effectively limits VDE to 20% opacity and meets the 

conditions of a stabilized unpaved road.

F.5.d Where compliance with any control measure in Rules 804 and 

805 is prohibited pursuant to F.5.c, the dust control plan must 

discuss and commit to implement other possible control 

measures, such as vehicle speed limits.

F.5.de The dust control plan must describe all PM-10 control measures 

that will be implemented, such as restricted use areas, 

stabilization of Unpaved Traffic Areas and current Recreation 

Area Management Plan (RAMP) measures, all applicable soil 

and habitat conservation requirements, and all monitoring and 

corrective actions taken to reduce PM10 emissions during OoffRroad Eevents and/or Ccompetitions on public land and include 

all those measures that are feasible and not prohibited by the 

laws, regulations and plans described in F.5.c;

F.5.ef Use BLM-standard road design and drainage specifications 

when maintaining existing roads or authorizing road 

maintenance and new road construction; and

F.5.fg Include public educational information on reducing PM-10 

emissions with agency (e.g., BLM or DPR) open area literature 
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(e.g. identification of restricted areas and/or applicable speed 

limits) and on related information signs in heavily used areas; 

and

F.5.g The owner or operator of a recreational OHV use area on public 

lands shall not permit Off-Road Events and/or Competitions 

from June 15th to August 15th, unless a specific dust control plan 

is submitted to and approved by the ICAPCD. The dust control 

plan shall include specific fugitive dust control measures and 

demonstrate that all control measures, including the 

requirements of this rule, can be implemented and enforced. 

F.6 Border Patrol (BP) Requirements

The BP shall prepare a dust control plan designed to minimize PM10 

emissions from sources under the control of the BP. The dust control plan 

shall include those dust control measures found in Rules 804 and 805. 

The dust control plan shall include the following fugitive dust control 

measures:

F.6.a A stipulation that all new authorizations for point and area 

stationary emission sources obtain all necessary permits and 

satisfy all applicable SIP provisions, including Regulation VIII 

specific control measures;

F.6.b Implement alternatives to tire-dragging that result in fewer PM10 

emissions, unless BP demonstrates such alternatives to be 

inconsistent with the monitoring of immigration across the U.S.-

Mexico border; and

F.6.c Control dust emissions from certain Unpaved Roads and routes 

owned or operated by the BP as identified through general BP 

planning consistent with Rule 805 unless those dust control 

measures are demonstrated to be inconsistent with BP authority 

and/or mission.

F.7 New Recreational OHV Use Area(s) on Public Land Requirements

Before a public agency (including BLM and DPR) designates a property as 

“New Recreational OHV Use Area” (hereafter referred to as “New 

Recreational OHV Use Area”) for OHV recreation, the agency shall meet 

and confer with ICAPCD. A “New Recreational OHV Use Area” shall 

include areas physically undisturbed by OHV usage as of January 1, 

2013. After development and approval of an agency’s first Dust Control 

Plan under Section D.3 of this rule, “New Recreational OHV Use Area also 
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Imperial County Rule 800, Final Settlement, June 20, 2012

includes areas not described in the previous public agency’s dust control 

plan.”

F.7.a ICAPCD shall review the public agency’s draft General Plan, 

Specific Plan, or RAMP and/or related documents for consistency 

and compliance with the rules and requirements applicable to 

and/or implementing Imperial County’s plan for attainment and/or 

maintenance of the 24-hour federal PM-10 standard. During the 

applicable public comment period, ICAPCD may provide comments 

on the applicable plan to the public agency related to consistency 

and compliance with such rules and requirements, and where 

applicable, describe additional measures necessary for consistency 

and compliance with such rules and requirements.

F.7.b For any New Recreational OHV Use Area(s) with PM-10 emissions 

of 70 tons per year or above, the public agency must demonstrate 

in a federal- and/or state-required environmental assessment that 

these emissions would not:

F.7.b.1 Cause or contribute to any new violations of any PM10 NAAQS in the area.

F.7.b.2 Interfere with provisions in the applicable PM-10 SIP 

for maintenance of the PM-10 NAAQS.

F.7.b.3 Increase the frequency or severity of any existing 

violation of PM-10 NAAQS; or

F.7.b.4 Delay timely attainment of the PM-10 NAAQS or any 

required interim emission reductions or other 

milestones in any area including, where applicable, 

emission levels specified in the applicable SIP for 

purposes of: (i) a demonstration of reasonable further 

progress; (ii) a demonstration of attainment; or (iii) a 

maintenance plan.

F.7.c The public agency shall not approve the applicable General Plan, 

Specific Plan, or RAMP unless and until it has incorporated 

ICAPCD’s comments and recommended mitigation measures or 

explained why a comment or recommended mitigation measure 

does not apply or is infeasible. If the public agency does not accept 

a mitigation measure or comment, the public agency shall consult 

with ICAPCD to identify an alternative measure or way to address 

ICAPCD’s concern. In any event, all New Recreational OHV Use 

Areas shall comply with Section F.5 above.
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Imperial County Rule 800, Final Settlement, June 20, 2012

G. Administrative Requirements

G.1 Test Methods

G.1.a Determination of VDE Opacity

Opacity observations to determine compliance with VDE 

standards shall be conducted in accordance with the test 

procedures for “Visual Determination of Opacity” as described in 

Appendix A of this rule. Opacity observations for sources other 

than unpaved traffic areas (e.g., roads, parking areas) shall be 

conducted per Section B of Appendix A and shall require 12 

readings at 15-second intervals.

G.1.b Determination of Stabilized Surface

Observations to determine compliance with the conditions 

specified for a stabilized surface, in any inactive disturbed 

surface area, whether at a work site that is under construction, 

at a work site that is temporarily or permanently inactive, or on 

an open area and vacant lot, shall be conducted in accordance 

with the test methods described in Appendix B of this rule. If a 

disturbed surface area passes any of the applicable Appendix 

B-Section A, B and D-G tests, then the surface shall be 

considered stabilized.

G.1.c Determination of Soil Moisture Content

Soil moisture content shall be determined by using ASTM 

Method D2216-98 (Standard Test Method for Laboratory 

Determination of Water [Moisture] Content of Soil and Rock by 

Mass), or other equivalent test methods approved by the EPA, 

ARB, and the APCO.

G.1.d Determination of Silt Content for Bulk Materials

Silt content of a Bulk Material shall be determined by ASTM 

Method C136a (Standard Test Method for Sieve Analysis of 

Fine and Coarse Aggregates), or other equivalent test methods 

approved by EPA, ARB, and the APCD.

G.1.e Determination of Silt Content for Unpaved Roads and Unpaved 

Vehicle/Equipment Traffic Areas

Silt Content for Unpaved Roads and Unpaved Traffic Areas 

shall be determined by using Section C of Appendix B of this 
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Rule or other equivalent test methods approved by EPA, ARB, 

and the APCO.

G.1.f Determination of Threshold Friction Velocity (TFV)

TFV shall be determined by using Section D of Appendix B of 

this Rule or other equivalent test methods approved by EPA, 

ARB, and the APCO.

H. Record of Control Implementation

Any Person subject to the requirements of this rule shall compile and retain 

records that provide evidence of control measure application and compliance 

with this rule (i.e., receipts and/or purchase records). Such Person shall 

describe, in the records, the type of treatment or control measure, extent of 

coverage, and date applied. For control measures which require multiple daily 

applications, recording the frequency of application will fulfill the recordkeeping 

requirements of this rule (i.e., water being applied three times a day and the 

date) Records shall be maintained and be readily accessible for two years after 

the date of each entry and shall be provided to the APCD upon request.

I. Violations

Failure to comply with any provisions of this rule shall constitute a violation of 

Regulation VIII. Failure to comply with the provisions of an APCO approved dust 

control plan shall also constitute a violation of this Regulation. Regardless of 

whether an APCO approved dust control plan is being implemented or not, or 

whether a Person responsible for an Active Operation(s) is complying with an 

approved dust control plan, the Person is still subject to the requirements of 

Regulation VIII at all times.
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Imperial County Rule 800, Final Settlement, June 20, 2012

APPENDIX A

Visual Determination of Opacity

SECTION A Test Method For Unpaved Roads and Unpaved Traffic Areas

SECTION B Test Method For Time-Averaged Regulations

SECTION A TEST METHOD FOR UNPAVED ROADS AND UNPAVED TRAFFIC 

AREAS

A. Opacity Test Method. The purpose of this test method is to estimate the percent 

opacity of Fugitive Dust plumes caused by vehicle movement on Unpaved Roads 

and Unpaved Traffic Areas. This method can only be conducted by an individual 

who has current certification as a qualified observer.

A.1 Step 1: Stand at least 16.5 feet from the fugitive dust source in order to 

provide a clear view of the emissions with the sun oriented in the 140° 

sector to the back. Following the above requirements, make opacity 

observations so that the line of vision is approximately perpendicular to the 

dust plume and wind direction. If multiple plumes are involved, do not 

include more than one plume in the line of sight at one time.

A.2 Step 2: Record the Fugitive Dust source location, source type, method of 

control used, if any, observer’s name, certification data and affiliation, and a 

sketch of the observer’s position relative to the Fugitive Dust source. Also, 

record the time, estimated distance to the Fugitive Dust source location, 

approximate wind direction, estimated wind speed, description of the sky 

condition (presence and color of clouds), observer’s position to the Fugitive 

Dust source, and color of the plume and type of background on the visible 

emission observation form both when opacity readings are initiated and 

completed.

A.3 Step 3: Make opacity observations, to the extent possible, using a 

contrasting background that is perpendicular to the line of vision. Make 

opacity observations approximately 1 meter above the surface from which 

the plume is generated. Note that the observation is to be made at only one 

visual point upon generation of a plume, as opposed to visually tracking the 

entire length of a dust plume as it is created along a surface. Make two 

observations per vehicle, beginning with the first reading at zero seconds 

and the second reading at five seconds. The zero-second observation 

should begin immediately after a plume has been created above the surface 

involved. Do not look continuously at the plume but, instead, observe the 

plume briefly at zero seconds and then again at five seconds.

A.4 Step 4: Record the opacity observations to the nearest 5% on an 

observational record sheet. Each momentary observation recorded 

represents the average opacity of emissions for a 5-second period. While it 
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is not required by the test method, EPA recommends that the observer 

estimate the size of the vehicles which generate dust plumes for which 

readings are taken (e.g. mid-size passenger car or heavy-duty truck.) and 

take the approximate speeds the vehicles are traveling when the readings 

are being taken.

A.5 Step 5: Repeat Step 3 (Section A.3. of this appendix) and Step 4 (Section 

A.4. of this appendix) until you have recorded a total of 12 consecutive 

opacity readings. This will occur once six vehicles have driven on the 

source in your line of observation for which you are able to take proper 

readings. The 12 consecutive readings must be taken within the same 

period of observation but must not exceed 1 hour. Observations 

immediately preceding and following interrupted observations can be 

considered consecutive.

A.6 Step 6: Average the 12 opacity readings together. If the average opacity 

reading equals 20% or lower, the source is in compliance with the opacity 

standard described in the applicable rule.

SECTION B TEST METHOD FOR VISUAL DETERMINATION OF OPACITY OF 

EMISSIONS FROM SOURCES FOR TIME-AVERAGED REGULATIONS

B. Applicability. This method is applicable for the determination of the opacity of 

emissions from sources of visible emissions for time-averaged regulations. A timeaveraged regulation is any regulation that requires averaging visible emission data 

to determine the opacity of visible emissions over a specific time period.

B.1 Principle. The opacity of emissions from sources of visible emissions is 

determined visually by a qualified observer who has received certification.

B.2 Procedures. A qualified observer who has been certified shall use the 

following procedures for visually determining the opacity of emissions.

B.2.a Position. Stand at a position at least 5 meters from the Fugitive 

Dust source n order to provide a clear view of the emissions with 

the sun oriented in the 140° sector to the back. Consistent as 

much as possible with maintaining the above requirements, make 

opacity observations from a position such that the line of sight is 

approximately perpendicular to the plume and wind direction. The 

observer may follow the Fugitive Dust plume generated by mobile 

earthmoving equipment, as long as the sun remains oriented in the 

140° sector to the back. As much as possible, if multiple plumes 

are involved, do not include more than one plume in the line of sight 

at one time.

B.2.b Field Records. Record the name of the site, Fugitive Dust source 
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type (i.e., pile, material handling (i.e., transfer, loading, sorting)), 

method of control used, if any, observer’s name, certification data 

and affiliation, and a sketch of the observer’s position relative to the 

Fugitive Dust source. Also, record the time, estimated distance to 

the Fugitive Dust source location, approximate wind direction, 

estimated wind speed, description of the sky condition (presence 

and color of clouds,) observer’s position relative to the fugitive dust 

source, and color of the plume and type of the background on the 

visible emission observation form when opacity readings are 

initiated and completed.

B.2.c Observations. Make opacity observations, to the extent possible, 

using a contrasting background that is perpendicular to the line of 

sight. For storage piles, make opacity observations approximately 

1 meter above the surface from which the plume is generated. For 

extraction operations and the loading of haul trucks in open-pit 

mines, make opacity observations approximately one meter above 

the rim of the pit. The initial observation should begin immediately 

after a plume has been created above the surface involved. Do not 

look continuously at the plume, but instead observe the plume 

momentarily at 15-second intervals. For Fugitive Dust from 

Earthmoving equipment, make opacity observations approximately 

1 meter above the mechanical equipment generating the plume.

B.2.d Recording Observations. Record the opacity observations to the 

nearest 5% every 15 seconds on an observational record sheet. 

Each momentary observation recorded represents the average 

opacity of emissions for a 15-second period. If a multiple plume 

exists at the time of an observation, do not record an opacity 

reading. Mark an “x” for that reading. If the equipment generating 

the plume travels outside of the field of observation, resulting in the 

inability to maintain the orientation of the sun within the 140° sector 

or if the equipment ceases operating, mark an “x” for the 15 –

second interval reading. Readings identified as “x” shall be 

considered interrupted readings.

B.2.e Data Reduction For Time-Averaged Regulations. For each set of 

12 or 24 consecutive readings, calculate the appropriate average 

opacity. Sets must consist of consecutive observations, however, 

readings immediately preceding and following interrupted readings 

shall be deemed consecutive and in no case shall two sets overlap, 

resulting in multiple violations.
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Imperial County Rule 800, Final Settlement, June 20, 2012

APPENDIX B

Determination of Stabilization

SECTION A Test Methods for Determining Stabilization

SECTION B Visible Crust Determination

SECTION C Determination of Silt Content for Unpaved Roads and Unpaved 

Vehicle/Equipment Traffic Areas

SECTION D Determination of Threshold Friction Velocity

SECTION E Determination of Flat Vegetative Cover

SECTION F Determination of Standing Vegetative Cover

SECTION G Rock Test Method

SECTION A TEST METHODS FOR DETERMINING STABLIZATION

The test methods described in Section B through Section G of this appendix shall 

be used to determine whether an area has a Stabilized Surface. Should a 

disturbed area contain more than one type of disturbance, soil, vegetation, or 

other characteristics, which are visibly distinguishable, test each representative 

surface separately for stability, in an area that represents a random portion of the 

overall disturbed conditions of the site, according to the appropriate test methods 

in Section B through Section G of this appendix, and include or eliminate it from 

the total size assessment of disturbed surface area(s) depending upon test 

method results.

SECTION B VISIBLE CRUST DETERMINATION

B.1 Where a visible crust exists, drop a steel ball with a diameter of 15.9 millimeters 

(0.625 inches) and a mass ranging from 16-17 grams from a distance of 30 

centimeters (one foot) directly above (at a 90° angle perpendicular to ) the soil 

surface. If blowsand is present, clear the blowsand from the surfaces on which 

the visible crust test method is conducted. Blowsand is defined as thin deposits 

of loose uncombined grains covering less than 50% of a site which have not 

originated from the representative site surface being tested. If material covers a 

visible crust, which is not blowsand, apply the test method in Section D of this 

appendix to the loose material to determine whether the surface is stabilized.

B.2 A sufficient crust is defined under the following conditions: once a ball has been 

dropped according to section B.1 of this appendix, the ball does not sink into the 

surface, so that it is partially or fully surrounded by loose grains and, upon 

removing the ball, the surface upon which it fell has not been pulverized, so that 

loose grains are visible.

B.3 Drop the ball three times within a survey area that measures 1 foot by 1 foot and 

that represents a random portion of the overall disturbed conditions of the site. 

The survey area shall be considered to have passed the Visible Crust 
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Determination Test if the results of at least two out of the three times that the ball 

was dropped, met the criteria in section B.2 of this appendix. Select at least two 

other survey areas that represent a random portion of the overall disturbed 

conditions of the site, and repeat this procedure. If the results meet the criteria of 

section B.2 of this appendix for all of the survey areas tested, then the site shall 

be considered to have passed the Visible Crust Determination Test and shall be 

considered sufficiently crusted.

B.4 At any given site, the existence of a sufficient crust covering one portion of the 

site may not represent the existence or protectiveness of a crust on another 

portion of the site. Repeat the visible crust test as often as necessary on each 

random portion of the overall conditions of the site for an accurate assessment.

SECTION C DETERMINATION OF SILT CONTENT FOR UNPAVED ROADS AND 

UNPAVED VEHICLE/EQUIPMENT TRAFFIC AREAS

The purpose of this test method is to estimate the silt content of the trafficked 

parts of Unpaved Roads and Unpaved vehicle/equipment Traffic Areas. The 

higher the Silt content, the more fine dust particles that are released when 

vehicles travel on Unpaved Roads and Unpaved vehicle/equipment Traffic Areas.

C.1 Equipment:

C.1.a. A set of sieves with the following openings: 4 millimeters (mm), 2mm, 

1mm, 0.5mm and 0.25 mm, a lid, and collector pan.

C.1.b A small whisk broom or paintbrush with stiff bristles and dustpan 1 ft. in 

width (the broom/brush should preferably have one, thin row of bristles no 

longer than 1.5 inches in length.)

C.1.c A spatula without holes.

C.1.d A small scale with half-ounce increments (e.g., postal/package scale.)

C.1.e A shallow, lightweight container (e.g., plastic storage container.)

C.1.f A sturdy cardboard box or other rigid object with a level surface.

C.1.g A basic calculator.

C.1.h Cloth gloves (optional for handling metal sieves on hot, sunny days.)

C.1.i Sealable plastic bags (if sending samples to a laboratory.)

C.1.j A pencil/pen and paper.

C.2 Step 1: Look for a routinely traveled surface, as evidenced by tire tracks. Only 

collect samples from surfaces that are not damp due to precipitation or dew. 

This statement is not meant to be a standard in itself for dampness where 

watering is being used as a control measure. It is only intended to ensure that 

surface testing is done in a representative manner. Use caution when taking 

samples to ensure personal safety with respect to passing vehicles. Gently 

press the edge of a dustpan (1 foot in width) into the surface four times to mark 

an area that is 1 square foot. Collect a sample of loose surface material into the 

dustpan, minimizing escape of dust particles. Use a spatula to lift heavier 
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elements such as gravel. Only collect dirt/Gravel to an approximate depth of 3/8 

inch or 1 cm in the 1 square foot area. If you reach a hard, underlying 

subsurface that is <3/8 inch in depth, do not continue collecting the sample by 

digging into the hard surface. In other words, you are only collecting a surface 

sample of loose material down to 1 cm. In order to confirm that samples are 

collected to a 1cm depth, a wooden dowel or other similar narrow object at least 

one-foot in length can be laid horizontally across the survey area while a metric 

ruler is held perpendicular to the dowel. (Optional: At this point, you can choose 

to place the sample collected into a plastic bag or container and take it to an 

independent laboratory for silt content analysis. A reference to the procedure the 

laboratory is required to follow is at the end of this section.)

C.3 Step 2: Place a scale on a level surface. Place a lightweight container on the 

scale. Zero the scale with the weight of the empty container on it. Transfer the 

entire sample collected in the dustpan to the container, minimizing escape of 

dust particles. Weigh the sample and record its weight.

C.4 Step 3: Stack a set of sieves in order according to the size openings specified 

above, beginning with the largest size opening (4mm) at the top. Place a 

collector pan underneath the bottom (0.25mm) sieve.

C.5 Step 4: Carefully pour the sample into the sieve stack, minimizing escape of dust 

particles by slowly brushing material into the stack with a whiskbroom or brush. 

On windy days, use the trunk or door of a vehicle as a wind barrier. Cover the 

stack with a lid. Lift up the sieve stack and shake it vigorously up and down and 

sideways for at least 1 minute.

C.6 Step 5: Remove the lid from the stack and disassemble each sieve separately, 

beginning with the top sieve. As you remove each sieve, examine it to make 

sure that all of the material has been sifted to the finest sieve through which it 

can pass (e.g., material in each sieve (besides the top sieve that captures a 

range of larger elements) should look the same size.) If this is not the case, restack the sieves and collector pan, cover the stack with the lid, and shake it again 

for at least 1 minute. You only need to reassemble the sieve(s) that contain 

material, which require further sifting.

C.7 Step 6: After disassembling the sieves and collector pan, slowly sweep the 

material from the collector pan into the empty container originally used to collect 

and weigh the entire sample. Take care not to minimize escape of dust particles. 

You do not need to do anything with material captured in the sieves – only the 

collector pan. Weigh the container with the materials from the collector pan and 

record its weight.

C.8 Step 7: If the source is an unpaved road, multiply the resulting weight by 0.38. If 

the source is an Unpaved vehicle/equipment Traffic Area, multiply the resulting 

weight by 0.55. The resulting number is the estimated silt loading. Then, divide
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the total weight of the sample you recorded earlier in Step 2 (Section C.4) and 

multiply by 100 to estimate the percent Silt content.

C.9 Step 8: Select another two routinely traveled portions of the Unpaved Road or 

Unpaved vehicle/equipment Traffic Area and repeat this test method. Once you 

have calculated the silt loading and percent silt content of the 3 samples 

collected, average your results together.

C.10 Step 9: Examine Results. If the average silt loading is less than 0.33 oz/ft2

, the 

surface is STABLE. If the average silt loading is greater than or equal to 0.33 

oz/ft2, then proceed to examine the average percent Silt content. If the source is 

an Unpaved Road and the average percent Silt content is 6% or less, the surface 

is STABLE. If the source is an unpaved parking lot and the average percent Silt 

content is 8% or less, the surface is STABLE. If your field test results are within 

2% of the standard (for example, 4%-8% Silt content on an Unpaved Road) it is 

recommended that you collect 3 additional samples from the source according to 

Step 1 (section C.2) and take them to an independent laboratory for Silt content 

analysis.

C.11 Independent Laboratory Analysis: You may choose to collect samples from the 

source, according to Step 1 (section C.2) and send them to an independent 

laboratory for Silt content analysis rather than conduct the sieve field procedure. 

If so, the test method the laboratory is required to use is: “Procedures For 

Laboratory Analysis for Surface/Bulk Dust Loading Samples,” (Fifth Edition, 

Volume 1, Appendix C.2.3 “Silt Analysis,” 1995,) AP-42, Office of Air Quality 

Planning & Standards, U.S. Environmental Protection Agency, Research Triangle 

Park, North Carolina.

SECTION D DETERMINATION OF THRESHOLD FRICTION VELOCITY (TFV)

For disturbed surface areas that are not crusted or vegetated, determine 

threshold friction velocity (TFV) according to the following sieving field procedure 

(based on a 1952 laboratory procedure published by W.S. Chepil).

D.1 Obtain and stack a set of sieves with the following openings: 4 millimeters (mm), 

2 mm, 1 mm, 0.5 mm, and 0.25 mm or obtain and stack a set of 

standard/commonly available sieves. Place the sieves in order according to size 

openings, beginning with the largest size opening at the top. Place a collector 

pan underneath the bottom (0.25 mm) sieve. Collect a sample of loose surface 

material from an area at least 30 cm by 30 cm in size to a depth of approximately 

1 cm using a brush and dustpan or other similar device. Only collect soil 

samples from dry surfaces (i.e. when the surface is not damp to the touch). 

Remove any rocks larger than 1 cm in diameter from the sample. Pour the 

sample into the top sieve (4 mm opening) and cover the sieve/collector pan unit 

with a lid. Minimize escape of particles into the air when transferring surface soil 

into the sieve/collector pan unit. Move the covered sieve/collector pan unit by 
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hand using a broad, circular arm motion in the horizontal plane. Complete twenty 

circular arm movements, ten clockwise and ten counterclockwise, at a speed just 

necessary to achieve some relative horizontal motion between the sieves and the 

particles. Remove the lid from the sieve/collector pan unit and disassemble each 

sieve separately beginning with the largest sieve. As each sieve is removed, 

examine it for loose particles. If loose particles have not been sifted to the finest 

sieve through which they can pass, reassemble and cover the sieve/collector pan 

unit and gently rotate it an additional ten times. After disassembling the 

sieve/collector pan unit, slightly tilt and gently tap each sieve and the collector 

pan so that material aligns along one side. In doing so, minimize escape of 

particles into the air. Line up the sieves and collector pan in a row and visibly 

inspect the relative quantities of catch in order to determine which sieve (or 

whether the collector pan) contains the greatest volume of material. If a visual 

determination of relative volumes of catch among sieves is difficult, use a 

graduated cylinder to measure the volume. Estimate TFV for the sieve catch 

with the greatest volume using Table 1 of this appendix, which provides a 

correlation between sieve opening size and TFV.

Table 1. Determination of Threshold Friction Velocity (TFV)

Tyler Sieve No. ASTM 11

Sieve No.

Opening

(mm)

TFV

(cm/s)

5 5 4 135

9 10 2 100

16 18 1 76

32 35 0.5 58

60 60 0.25 43

Collector Pan --- --- 30

D.2 Collect at least three soil samples which represent random portions of the overall 

conditions of the site, repeat the above TFV test method for each sample and 

average the resulting TFVs together to determine the TFV uncorrected for non 

erodible elements. Non-erodible elements are distinct elements, in the random 

portion of the overall conditions of the site, that are larger than 1 cm in diameter, 

remain firmly in place during a wind episode, and inhibit soil loss by consuming 

Section of the shear stress of the wind. Non-erodible elements include stones 

and bulk surface material but do not include flat or standing vegetation. For 

surfaces with non-erodible elements, determine corrections to the TFV by 

identifying the fraction of the survey area, as viewed from directly overhead, that 

is occupied by non-erodible elements using the following procedure. Select a 

survey area of 1 meter by 1 meter that represents a random portion of the overall 

conditions of the site. Where many non-erodible elements lie within the survey 

area, separate the non-erodible elements into groups according to size. For 

each group, calculate the overhead area for the non-erodible elements according 

to the following equations: 
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Average Dimensions =

(Average Length) x ( Average Width) Eq. 1

Overhead Area =

(Average Dimensions) x (Number of Elements) Eq. 2

Total Overhead Area =

Overhead Area Of Group 1 + Overhead Area of Group 2 

(etc)

Eq. 3

Total Frontal Area =

Total Overhead Area/2 Eq. 4

Percent Cover of Non-Erodible Elements =

(Total Frontal Area/Survey Area) x 100 Eq. 5

Note: Ensure consistent units of measurements (e.g., square meters or square 

inches when calculating percent cover).

Repeat this procedure on an additional two distinct survey areas that represent a 

random portion of the overall conditions of the site and average the results. Use 

Table 2 of this appendix to identify the correction factor for the percent cover of 

non-erodible elements. Multiply the TFV by the corresponding correction factor 

to calculate the TFV corrected for non-erodible elements.

Table 2. Correction Factors for Threshold Friction Velocity

Percent Cover of Non-Erodible Elements Correction Factor

Greater than or equal to 10% 5

Greater than or equal to 5% and less than 

10%

3

Less than 5% and greater than or equal 

to 1%

2

Less than 1% None

SECTION E DETERMINATION OF FLAT VEGETATIVE COVER

Flat vegetation includes attached (rooted) vegetation or unattached vegetative 

debris lying on the surface with a predominant horizontal orientation that is not 

subject to movement by wind. Flat vegetation, which is dead but firmly attached, 

shall be considered equally protective as live vegetation. Stones or other 
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aggregate larger than 1 centimeter in diameter shall be considered protective 

cover in the course of conduction the line transect test method. Where flat 

vegetation exists conduct the following line transect test method.

E.1 Line Transect Test Method. Stretch a 100 foot measuring tape across a survey 

area that represents a random portion of the overall conditions of the site. Firmly 

anchor both ends of the measuring tape into the surface using a tool such as a 

screwdriver, with the tape stretched taut and close to the soil surface. If 

vegetation exists in regular rows, place the tape diagonally (at approximately a 

45° angle) away from a parallel or perpendicular position to the vegetated rows. 

Pinpoint an area the size of a 3/32 inch diameter brazing rod or wooden dowel 

centered above each 1 foot interval mark along one edge of the tape. Count the 

number of times that flat vegetation lies directly underneath the pinpointed area 

at 1 foot intervals. Consistently observe the underlying surface from a 90° angle 

directly above each pinpoint on one side of the tape. Do not count the underlying 

surface as vegetated if any portion of the pinpoint extends beyond the edge of 

the vegetation underneath in any direction. If clumps of vegetation or vegetative 

debris lie underneath the pinpointed area, count the surface as vegetated, unless 

bare soil is visible directly below the pinpointed area. When 100 observations 

have been made, add together the number of times a surface was counted as 

vegetated. This total represents the percent of flat vegetations cover (e.g., if 35 

positive counts were made, then vegetation cover is 35%.) If the survey area 

that represents a random portion of the overall conditions of the site is too small 

for 100 observations, make as many observations as possible. Then multiply the 

count of vegetated surface areas by the appropriate conversion factor to obtain 

percent cover. For example, if vegetation was counted 20 times within a total of 

50 observations, divide 20 by 50 and multiply by 100 to obtain a flat vegetation 

cover of 40%.

E.2 Conduct the line transect test method, as described in section E.1 of this 

appendix, an additional two times on areas that represent a random portion of 

the overall conditions of the site and average results. 

SECTION F DETERMINATION OF STANDING VEGETATIVE COVER.

Standing vegetation includes vegetation that is attached (rooted) with a 

predominant vertical orientation. Standing vegetation, which is dead but firmly 

rooted, shall be considered equally protective as live vegetation. Conduct the 

following standing vegetation test method to determine if 30% cover or more 

exists. If the resulting percent cover is less than 30% but equal to or greater than 

10%, then conduct the test in Section D; “Determination Of Threshold Friction 

Velocity (TFV,) of this appendix in order to determine if the site is stabilized, such 

that the standing vegetation cover is equal to or greater than 10%, where 

threshold friction velocity, corrected for non-erodible elements, is equal to or 

greater than 43cm/second.
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F.1 For standing vegetation that consists of large, separate vegetative structures 

(e.g., shrubs and sagebrush,) select a survey area that represents a random 

portion of the overall conditions of the site that is the shape of a square with 

sides equal to at least 10 times the average height of the vegetative structures. 

For smaller standing vegetation, select a survey area of three feet by three feet.

F.2 Count the number of standing vegetative structures within the survey area. 

Count vegetation, which grows in clumps as a single unit. Where different types 

of vegetation exist and/or vegetation of different height and width exists, separate 

the vegetative structures with similar dimensions into groups. Count the number 

of vegetative structures in each group within the survey area. Select an 

individual structure within each group that represents the average height and 

width of the vegetation in the group. If the structure is dense (e.g., when looking 

at it vertically from base to top there is little or zero open air space within its 

perimeter,) calculate and record its frontal silhouette area, according to Equation 

6 of this appendix. Also, use Equation 6 of this appendix to estimate the average 

height and width of the vegetation if the survey area is larger than nine square 

feet. Otherwise, use the procedure in section F.3 of this appendix to calculate 

the frontal silhouette area. Then calculate the percent cover of standing 

vegetation according to Equations 7, 8, and 9 of this appendix.

Frontal Silhouette Area =

(Average Height) x (Average Width) Eq. 6

Frontal Silhouette Area Of Group=

(Frontal Silhouette Area Of Individual Vegetative Structure) 

x (Number Of Vegetation Structures Per Group)

Eq. 7

Total Frontal Silhouette Area =

Frontal Silhouette Area Of Group 1 + Frontal Silhouette 

Area Of Group 2 (etc.)

Eq. 8

Percent Cover Of Standing Vegetation =

(Total Frontal Silhouette Area/Survey Area) x 100 Eq. 9

Percent Open Space =

[(Number Of Circled Gridlines Within The Outlined Area 

Counted That Are Not Covered By Vegetation/Total Number 

Of Gridline Intersections Within The Outlined Area) x 100]

Eq.10

Percent Vegetative Density =

100 – Percent Open Space Eq. 11

Vegetative Density =

Percent Vegetative Density/100 Eq. 12
Imperial County Air Pollution Control District Rule 800

Imperial County Rule 800, Final Settlement, June 20, 2012

Note: Ensure consistent units of measurement (e.g., square meters or square 

inches when calculating percent cover.)

F.3. Vegetative Density Factor. Cut a single, representative piece of vegetation (or 

consolidated vegetative structure) to within 1cm of surface soil. Using a white 

paper grid or transparent grid over white paper, lay the vegetation flat on top of 

the grid (but do not apply pressure to flatten the structure.) Grid boxes of 1 inch 

or 1⁄2 inch squares are sufficient for most vegetation when conducting this 

procedure. Using a marker or pencil, outline the shape of the vegetation along 

its outer perimeter, according to Figure B, C, or D of this appendix, as 

appropriate. (Note: Figure C differs from Figure D primarily in that the width of 

vegetation in Figure C is narrow at its base and gradually broadens to its tallest 

height. In Figure D, the width of the vegetation generally becomes narrower from 

its midpoint to its tallest height.) Remove the vegetation, count and record the 

total number of gridline intersections within the outlined area, but do not count 

gridline intersections that connect with the outlined shape. There must be at 

least 10 gridline intersections within the outlined area and preferably more than 

Frontal Silhouette Area =

[Max. Height x Max. Width] x [Vegetative Density/.04]o.5 Eq. 13
Imperial County Air Pollution Control District Rule 800

Imperial County Rule 800, Final Settlement, June 20, 2012

20, otherwise, use smaller grid boxes. Draw small circles (no greater than a 3/32 

inch diameter) at each gridline intersection counted within the outlined area. 

Replace the vegetation on the grid within its outlined shape. From a distance of 

approximately 2 feet directly above the grid, observe each circled gridline 

intersection. Count and record the number of circled gridline intersections that 

are not covered by any piece of the vegetation. To calculate percent vegetative 

density, use Equations 10 and 11 of this appendix. If percent vegetative density 

is equal to or greater than 30, use an equation (one of the equations-Equations 

16, 17, or 18 of this appendix) that matches the outline used to trace the 

vegetation (Figure B, C, or D) to calculate its frontal silhouette area. If percent 

vegetative density is less than 30, use Equations 12 and 13 of this appendix to 

calculate the frontal silhouette area.

Figure B. Cylinder

Frontal Silhouette Area = Maximum Height x Maximum Width Eq.16

Figure C. Inverted Cone

Frontal Silhouette Area = Maximum Height x 1⁄2 Maximum Width Eq. 17
Imperial County Air Pollution Control District Rule 800

Imperial County Rule 800, Final Settlement, June 20, 2012

Figure D. Upper Sphere

Frontal Silhouette Area = (3.14 x Maximum Height x 1⁄2 Maximum Width)/2 Eq.18

SECTION G ROCK TEST METHOD

The Rock Test Method, which is similar to Section D, Test Methods For 

Stabilization-Determination Of Threshold Friction Velocity (TFV) of this appendix, 

examines the wind-resistance effects of rocks and other non-erodible elements 

on disturbed surfaces. Non-erodible elements are objects larger than 1 

centimeter (cm) in diameter that remain firmly in place even on windy days. 

Typically, non-erodible elements include rocks, stones, glass fragments, and 

hardpacked clumps of soil lying on or embedded in the surface. Vegetation does 

not count as a non-erodible element in this method. The purpose of this test 

method is to estimate the percent cover of non-erodible elements on a given 

surface to see whether such elements take up enough space to offer protection

against windblown dust. For simplification, the following test method refers to all 

non-erodible elements as ‘rocks.”

G.1 Select a 1 meter by 1 meter survey area that represents the general rock 

distribution on the surface. A 1 meter by 1 meter area is slightly greater than a 3 

foot by 3 foot area. Mark-off the survey area by tracing a straight, visible line in 

the dirt along the edge of a measuring tape or by placing short ropes, yard sticks, 

or other straight objects in a square around the survey area.

G.2 Without moving any of the rocks or other elements, examine the survey area. 

Since rocks >3/8 inch (1cm) in diameter are of interest, measure the diameter of 

some of the smaller rocks to get a sense of which rocks need to be considered.

G.3 Mentally group the rocks >3/8 inch (1cm) diameter lying in the survey area into 

small, medium, and large size categories. Or, if the rocks are all approximately 

the same size, simply select a rock of average size and typical shape. Without 

removing any of the rocks from the ground, count the number of rocks in the 

survey area in each group and write down the resulting number.

G.4 Without removing rocks, select one or two average-size rocks in each group and 

measure the length and width. Use either metric units or standard units. Using a 
Imperial County Air Pollution Control District Rule 800

Imperial County Rule 800, Final Settlement, June 20, 2012

calculator, multiply the length times the width of the rocks to get the average 

dimensions of the rocks in each group. Write down the results for each rock 

group.

G.5 For each rock group, multiply the average dimensions (length times width) by the 

number of rocks counted in the group. Add the results from each rock group to 

get the total rock area within the survey area.

G.6 Divide the total rock area, calculated in section G.5 of this appendix, by two (to 

get frontal area.) Divide the resulting number by the size of the survey area 

(make sure the units of measurement match,) and multiply by 100 for percent 

rock cover. For example, the total rock area is 1,400 square centimeters divide 

1,400 by 2 to get 700. Divide 700 by 10,000 (the survey area is 1 meter by 1 

meter, which is 100 centimeters by 100 centimeters or 10,000 centimeters) and 

multiply by 100. The result is 7% rock cover. If rock measurements are made in 

inches, convert the survey area from meters to inches (1 inch = 2.54 

centimeters.)

G.7 Select and mark-off two additional survey areas and repeat the procedures 

described in section G.1 through section G.6 of this appendix. Make sure the 

additional survey areas also represent the general rock distribution on the site. 

Average the percent cover results from all three survey areas to estimate the 

average percent of rock cover.

G.8 If the average rock cover is greater than or equal to 10%, the surface is stable. If 

the average rock cover is less than 10%, follow the procedures in section G.9 of 

this appendix.

G.9 If the average rock cover is less than 10%, the surface may or may not be stable. 

Follow the procedures in Section D.3 Determination Of Threshold Friction 

Velocity (TFV) of this rule and use the results from the rock test method as a 

correction (i.e., multiplication) factor. If the rock cover is at least 1%, such rock 

cover helps to limit windblown dust. However, depending on the soil’s ability to 

release fine dust particles into the air, the percent rock cover may or may not be 

sufficient enough to stabilize the surface. It is also possible that the soil itself has 

a high enough TFV to be stable without even accounting for rock cover.

G.10 After completing the procedures described in Section G.9 of this appendix, use 

Table 2 of this appendix to identify the appropriate correction factor to the TFV, 

depending on the percent rock cover.
Imperial County Air Pollution Control District Rule 801

Imperial County Rule 801, Final Settlement, June 20, 2012

RULE 801 CONSTRUCTION AND EARTHMOVING ACTIVITIES

(Adopted 11/08/2005)

A. Purpose

The purpose of this rule is to reduce the amount of fine Particulate Matter 

(PM-10) entrained in the ambient air as a result of emissions generated from 

Construction and other Earthmoving Activities by requiring actions to prevent, 

reduce, or mitigate PM-10 emissions.

B. Applicability

This rule applies to any Construction and other Earthmoving Activities, including, 

but not limited to, land clearing, excavation related to construction, land leveling, 

grading, cut and fill grading, erection or demolition of any structure, cutting and 

filling, trenching, loading or unloading of bulk materials, demolishing, drilling, 

adding to or removing bulk of materials from open storage piles, weed abatement 

through disking, back filling, travel on-site and travel on access roads to and from 

the site.

C. Definitions

The definitions of terms found in Rule 800 (General Requirements for Control of 

Fine Particulate Matter (PM-10) shall apply to this rule.

D. Exemptions

In addition to the exemptions listed in Rule 800, Section E, the following 

exemptions are established for this rule:

D.1 Construction or demolition at existing single family residential dwellings.

D.2 The 20% opacity limit of Sections E.1.a and E.2.b shall not apply when 

Wind Gusts exceed 25 miles per hour, provided that at least one of the 

following control measures is implemented for each applicable Fugitive 

Dust source type:

D.2.a Cease dust generating activities for a period of one hour after Wind 

Gusts last exceed the threshold. If operations cease for the 

remainder of the day, stabilization measures must be implemented.

D.2.b Apply water or dust Suppressants once per hour.

D.2.c Apply water to maintain 12% soil moisture content.

D.2.d Construct fences 3-5 feet high with 50% or less porosity, and must 
Imperial County Air Pollution Control District Rule 801

Imperial County Rule 801, Final Settlement, June 20, 2012

be done in conjunction with another measure, as above.

E. Requirements

E.1 Construction sites and Earthmoving Activities: 

E.1.a All Persons who own or operate a Construction site shall comply 

with the requirements of Section F.1 so as to limit VDE to 20% 

opacity and comply with the conditions for a Stabilized Surface 

when applicable.

E.1.b All Persons who perform any Earthmoving Activities shall comply 

with the requirements of Section F.1 so as to limit VDE to 20% 

opacity.

E.1.c All Persons who own or operate a Construction site of 10 acres or 

more in size for residential developments or 5 acres or more for 

non-residential developments shall develop a dust control plan. The 

dust control plan shall be made available to the APCD upon 

request. The dust control plan shall comply with the requirements 

of Section F.

E.1.d The owner or operator required to develop a dust control plan shall 

provide written notification to the APCD within 10 days prior to the 

commencement of any Construction activities via fax or mail. The 

requirement to develop a dust control plan shall apply to all such 

activities conducted for residential and non-residential (e.g., 

commercial, industrial, or institutional) purposes or conducted by 

any governmental entity. Regardless of whether a dust control plan 

is in place or not the owner or operator is still subject to comply with 

all requirements of the applicable rules under Regulation VIII at all 

times.

F. Best Available Control Measures for Fugitive Dust (PM-10)

F.1 Construction and Earthmoving Activities shall comply with the following 

requirements:

F.1.a Pre-Activity:

F.1.a.1 Pre-water site sufficient to limit VDE to 20% opacity, and

F.1.a.2 Phase work to minimize the amount of disturbed surface 

area at any one time.

F.1.b During Active Operations:
Imperial County Air Pollution Control District Rule 801

Imperial County Rule 801, Final Settlement, June 20, 2012

F.1.b.1 Apply water or Chemical Stabilization as directed by 

product manufacturer to limit VDE to 20% opacity, or

F.1.b.2 Construct and maintain wind barriers sufficient to limit 

VDE to 20% opacity. If utilizing wind barriers, control 

measure F.1.b.1 above shall be implemented.

F.1.b.3 Apply water or Chemical Stabilization as directed by 

product manufacturer to unpaved haul/access roads and 

Unpaved Traffic Areas sufficient to limit VDE to 20% 

opacity and meet the conditions of a Stabilized Unpaved 

Road.

F.1.c Temporary Stabilization During Periods of Inactivity:

F.1.c.1 Restrict vehicular access to the area by fencing or 

signage; and

F.1.c.2 Apply water or Chemical Stabilization, as directed by 

product manufacturer, sufficient to comply with the 

conditions of a Stabilized Surface. If an area having 0.5 

acres or more of disturbed surface area remains unused 

for seven or more days, the area must comply with the 

conditions for a Stabilized Surface area.

F.1.d Track Out/Carry Out of Bulk Materials at the site shall be mitigated 

in compliance with Rule 803.

F.1.e Unpaved Roads and Unpaved Traffic Areas at the site shall comply 

with Rule 805.

F.1.f Bulk Material handling operations at the site shall comply with Rule 

802.

F.1.g Material transport of Bulk Material to, from, or around the site shall 

comply with Rule 802.

F.1.h Haul trucks transporting Bulk Material to, from, or around the site 

shall comply with Rule 802.

F.2 Dust Control Plan:

F.2.a Retain a copy of the dust control plan at the project site.
Imperial County Air Pollution Control District Rule 801

Imperial County Rule 801, Final Settlement, June 20, 2012

F.2.b Comply with the requirements of the approved dust control plan.

F.2.c A dust control plan shall contain all of the following information:

1. Name, address, and phone number of the Person 

responsible for the preparation, submittal, and 

implementation of the dust control plan and responsible for 

the project site.

2. A plot plan which shows the type and location of each 

project.

3. The total area of land surface to be disturbed, estimated 

daily throughput volume of earthmoving in cubic yards, and 

total area in acres of the entire project site.

4. The expected start and completion dates of dust generating 

and soil disturbance activities to be performed on the site.

5. The actual and potential sources of Fugitive Dust emissions 

on the site and the location of Bulk Material handling and 

storage areas, Paved and Unpaved Roads, entrances and 

exits where Track Out/Carry Out may occur, and Unpaved 

Traffic Areas.

6. Dust Suppressants to be applied, including: product 

specifications; manufacturer's usage instructions (method, 

frequency, and intensity of application); type, number, and 

capacity of application equipment; and information on 

environmental impacts and approvals or certifications related 

to appropriate and safe use for ground application.

7. Specific surface treatment(s) and/or control measures 

utilized to control Track Out/Carry Out, and sedimentation 

where unpaved and/or access points join paved public 

access roads.

8. The dust control plan should describe all Fugitive Dust 

control measures to be implemented before, during, and 

after any dust generating activity.

G. Record of Control Implementation

Any Person subject to the requirements of this rule shall compile and retain 

records that provide evidence of control measure application (i.e., receipts and/or 

purchase records). Such Person shall describe, in the records, the type of 
Imperial County Air Pollution Control District Rule 801

Imperial County Rule 801, Final Settlement, June 20, 2012

treatment or control measure, extent of coverage, and date applied. For control 

measures which require multiple daily applications, recording the frequency of 

application will fulfill the recordkeeping requirements of this rule (i.e., water being 

applied three times a day and the date) Records shall be maintained and be 

readily accessible for two years after the date of each entry and shall be provided 

to the APCD upon request.

H. Violations

Failure to comply with any provisions of this rule shall constitute a violation of 

Regulation VIII. 
Imperial County Air Pollution Control District Rule 802

Imperial County Rule 802, Final Settlement, June 20, 2012

RULE 802 BULK MATERIALS

(Adopted 11/08/2005)

A. Purpose

The purpose of this regulation is to reduce the amount of fine Particulate Matter 

(PM-10) entrained in the ambient air as a result of emissions generated from 

outdoor handling, storage, and transport of Bulk Material by requiring actions to 

prevent, reduce, or mitigate PM-10 emissions.

B. Applicability

This rule applies to the outdoor handling, storage, and transport of Bulk Material, 

including, but not limited to, earth, rock, silt, sediment, sand, gravel, soil, fill, 

Aggregate Materials, dirt, mud, debris, and other organic and/or inorganic 

material consisting of or containing Particulate Matter with five percent or greater 

silt content.

C. Definitions

The definitions of terms found in Rule 800 (General Requirements for Control of 

Fine Particulate Matter (PM-10) shall apply to this rule.

D. Exemptions

In addition to the exemptions listed in Rule 800, Section E, the following 

exemptions are established for this rule:

D.1 Outdoor storage, transport, or handling of Bulk Materials (including, but 

not limited to, organic or inorganic fertilizer, grains, seed, soil 

amendments, and feed) which would be damaged by wetting with water or 

by the application of Chemical Stabilization/Suppression, provided 

owners/operators demonstrate to the satisfaction of the APCO that none 

of the control measures required by this rule can be implemented to limit 

VDE to 20% opacity or provide a Stabilized Surface, as defined in Rule 

800.

D.2 Outdoor storage or handling of any Bulk Material at a single site where no 

material is actively being added or removed at the end of the workday or 

overnight and where the total material stored is less than 100 cubic yards.

D.3 Transport of a Bulk Material in an outdoor area for a distance of twelve 

feet or less with the use of a chute or conveyor device.

D.4 Transport/hauling of Bulk Materials when conducted within the boundaries 

of a premises, are exempt from the requirements specified in Sections 
Imperial County Air Pollution Control District Rule 802

Imperial County Rule 802, Final Settlement, June 20, 2012

F.3.a and F.3.d.

E. Requirements

E.1 Bulk Material handling: no Person shall cause, suffer, allow or engage in 

any Bulk Material handling operation including, but not limited to stacking, 

loading, unloading, conveying and reclaiming of Bulk Material, for 

industrial or commercial purposes without complying with one or more of 

the requirements of Section F.1 so as to limit VDE to 20% opacity.

E.2 Bulk Material storage: no Person shall cause, suffer, allow or engage in 

any Bulk Material storage, for industrial or commercial purposes without 

complying with one or more of the requirements of Section F.2 so as to 

limit VDE to 20% opacity.

E.3 Material transport: no Person shall cause, suffer, allow or otherwise 

engage in the transportation of Bulk Materials for industrial or commercial 

purposes, without complying with all of the requirements of Section F.3 so 

as to limit VDE to 20% opacity.

E.4 Haul Trucks: no Person shall cause, suffer, allow or otherwise engage in 

the use or operation of any Haul Truck, for industrial or commercial 

purposes, of transporting or storing Bulk Material without complying with 

all of the requirements of Section F.3 so as to limit VDE to 20% opacity.

F. Best Available Control Measures for Fugitive Dust (PM-10)

F.1 BULK MATERIAL HANDLING/TRANSFER:

F.1.a Spray with water prior to handling and/or at points of transfer; or.

F.1.b Apply and maintain Chemical Stabilization, or

F.1.c Protect from wind erosion by sheltering or enclosing the operation 

and transfer line.

F.2 BULK MATERIAL STORAGE

F.2.a When storing Bulk Materials, comply with the conditions for a 

Stabilized Surface; or

F.2.b Cover Bulk Materials stored outdoors with tarps, plastic, or other 

suitable material and anchor in such a manner that prevents the 

cover from being removed by wind action, or

F.2.c Construct and maintain barriers with less than 50% porosity. If 
Imperial County Air Pollution Control District Rule 802

Imperial County Rule 802, Final Settlement, June 20, 2012

utilizing fences or wind barriers, apply water or chemical/organic 

stabilizers/suppressants, or

F.2.d Utilize a 3-side structure with a height at least equal to the height of 

the storage pile and with less than 50% porosity.

F.3 MATERIAL TRANSPORT/HAULING:

F.3.a Completely cover or enclose all Haul Truck loads of Bulk Material.

F.3.b Haul Trucks transporting loads of Aggregate Materials shall not be 

required to cover their loads if the load, where it contacts the side, 

front, and back of the cargo container area remains six inches from 

the upper area of the container area, and if the load does not 

extend, at its peak, above any part of the upper edge of the cargo 

container area (As defined in Section 23114 of the California 

Vehicle Code for both public and private roads).

F.3.c The cargo compartment(s) of all Haul Trucks are to be constructed 

and maintained so that no spillage and loss of Bulk Material can 

occur from holes or other openings in the cargo compartment's 

floor, side, and/or tailgate. Seals on any openings used to empty 

the load including, but not limited to, bottom-dump release gates 

and tailgates to be properly maintained to prevent the loss of Bulk 

Material from those areas.

F.3.d The cargo compartment of all Haul Trucks is to be cleaned and/or 

washed at delivery site after removal of Bulk Material.

G. Record of Control Implementation

Any Person subject to the requirements of this rule shall compile and retain 

records that provide evidence of control measure application (i.e., receipts and/or 

purchase records). Such Person shall describe, in the records, the type of 

treatment or control measure, extent of coverage, and date applied. For control 

measures which require multiple daily applications, recording the frequency of 

application will fulfill the recordkeeping requirements of this rule (i.e., water being 

applied three times a day and the date) Records shall be maintained and be 

readily accessible for two years after the date of each entry and shall be provided 

to the APCD upon request.

H. Violations

Failure to comply with any provisions of this rule shall constitute a violation of 

Regulation VIII. 
Imperial County Air Pollution Control District Rule 803

Imperial County Rule 803, Final Settlement, June 20, 2012

RULE 803 CARRY-OUT AND TRACK-OUT

(Adopted 11/08/2005)

A. Purpose

The purpose of this regulation is to reduce the amount of fine Particulate Matter 

(PM-10) entrained in the ambient air as a result of emissions generated from 

Track-Out and Carry-Out by requiring actions to prevent, reduce, or mitigate 

PM-10 emissions.

B. Applicability

This rule applies to all sites that are subject to Regulation VIII where Track-Out or 

Carry-Out has occurred or may occur on paved public roads or the paved 

shoulders of a paved public road.

C. Definitions

The definitions of terms found in Rule 800 (General Requirements for Control of 

Fine Particulate Matter (PM-10) shall apply to this rule.

D. Exemptions:

In addition to the exemptions listed in Rule 800, Section E, the following 

exemptions are established for this rule:

D.1 Agricultural Operation Sites defined in and subject to Rule 806, 

Conservation Management Practices, are exempt from the requirements 

specified in Sections F.1.b and F.1.c.

D.2 Any operation site that operates no more than 10 days within a 90 days 

period at each location is exempt from the requirements specified in 

Sections F.1.b and F.1.c. 

E. Requirements

E.1 Track Out/Carry Out: any Person who causes the deposition of Bulk 

Material by tracking out or carrying out onto a Paved Road surface shall

comply with the requirements of Section F.1, as specified, to prevent or 

mitigate such deposition.

F. Best Available Control Measures for Fugitive Dust (PM-10)

F.1 TRACK OUT/CARRY OUT:

F.1.a Clean up any Bulk Material tracked out or carried out onto a Paved 
Imperial County Air Pollution Control District Rule 803

Imperial County Rule 803, Final Settlement, June 20, 2012

Road on the following time-schedule:

(1) Within urban areas, immediately, when Track-Out or CarryOut extends a cumulative distance of 50 linear feet or more; 

and

(2) At the end of the workday, for all other Track-Out or CarryOut.

F.1.b In addition to F.1.a, all sites with access to a Paved Road and with 

150 or more Average Vehicle Trips per Day, or 20 or more Average 

Vehicle Trips per Day by vehicles with three or more axles shall 

install one or more Track-Out Prevention Devices or other APCO 

approved Track-Out control device or wash down system at access 

points where unpaved traffic surfaces adjoin Paved Roads; or

F.1.c In addition to F.1.a, all sites with access to a Paved Road and with 

150 or more Average Vehicle Trips per Day, or 20 or more Average 

Vehicle Trips per Day by vehicles with three or more axles shall 

apply and maintain paving, Chemical Stabilizeation, or at least 3 

inch depth of Gravel (using Gravel or other low Silt (<5%) content 

material), for a distance of 50 or more consecutive feet at access 

points where Unpaved Roads adjoin Paved Roads. 

G. Record of Control Implementation

Any Person subject to the requirements of this rule shall compile and retain 

records that provide evidence of control measure application (i.e., receipts and/or 

purchase records). Such Person shall describe, in the records, the type of 

treatment or control measure, extent of coverage, and date applied. Records 

shall be maintained and be readily accessible for two years after the date of each 

entry and shall be provided to the APCD upon request. 

H. Violations

Failure to comply with any provisions of this rule shall constitute a violation of 

Regulation VIII. 
Imperial County Air Pollution Control District Rule 804

Imperial County Rule 804, Final Settlement, June 20, 2012

RULE 804 OPEN AREAS

(Adopted 11/08/2005; revised XXXX)

A. Purpose

The purpose of this regulation is to reduce the amount of fine Particulate Matter 

(PM-10) entrained in the ambient air as a result of emissions generated from 

Open Areas by requiring actions to prevent, reduce, or mitigate PM-10 

emissions.

B. Applicability

This rule shall apply to any open area having 0.5 acres or more within urban 

areas, or 3.0 acres or more within rural areas; and contains at least 1000 square 

feet of disturbed surface area.

C. Definitions

The definitions of terms found in Rule 800 (General Requirements for Control of 

Fine Particulate Matter (PM-10) shall apply to this rule.

D. Exemptions

In addition to the exemptions listed in Rule 800, Section E, the following 

exemptions are established for this rule:

D.1 Agricultural Operation Sites defined in and subject to Rule 806, 

Conservation Management Practices.

D.2 Recreational OHV Use Areas on public lands subject to Rule 800, General 

Requirements for Control of Fine Particulate Matter (PM-10).

E. Requirements

E.1 Open Areas: all Persons who own or otherwise have jurisdiction over an 

Open Area shall comply with one or more of the requirements of Section 

F.1 to comply with the conditions of a Stabilized Surface at all times and 

limit VDE to 20% opacity.

E.2 Vehicle use in Open Areas: within 30 days following initial discovery of 

evidence of trespass, a Person who owns or otherwise has jurisdiction 

over an Open Area shall prevent unauthorized vehicle access by posting 

"No Trespassing" signs or installing physical barriers such as fences, 

gates, posts, and/or appropriate barriers to effectively prevent access to 

the area. 
Imperial County Air Pollution Control District Rule 804

Imperial County Rule 804, Final Settlement, June 20, 2012

F. Best Available Control Measures for Fugitive Dust (PM-10)

F.1 OPEN AREAS

F.1.a Apply and maintain water or dust suppressant(s) to all unvegetated 

areas.

F.1.b Establish vegetation on all previously disturbed areas.

F.1.c Pave, apply and maintain Gravel, or apply and maintain Chemical 

Stabilizers/Suppressants

G. Record of Control Implementation

Any Person subject to the requirements of this rule shall compile and retain 

records that provide evidence of control measure application (i.e., receipts and/or 

purchase records). Such Person shall describe, in the records, the type of 

treatment or control measure, extent of coverage, and date applied. For control 

measures which require multiple daily applications, recording the frequency of 

application will fulfill the recordkeeping requirements of this rule (i.e., water being 

applied three times a day and the date) Records shall be maintained and be 

readily accessible for two years after the date of each entry and shall be provided 

to the APCD upon request.

H. Violations

Failure to comply with any provisions of this rule shall constitute a violation of 

Regulation VIII. 
Imperial County Air Pollution Control District Rule 805

Imperial County Rule 805, Final Settlement, June 20, 2012

RULE 805 PAVED AND UNPAVED ROADS

(Adopted 11/08/2005; revised XXXX))

A. Purpose

The purpose of this regulation is to reduce the amount of fine Particulate Matter (PM-10) 

entrained in the ambient air as a result of emissions generated from new or existing 

public or private Paved or Unpaved Road, road construction project, or road modification 

project by requiring actions to prevent, reduce, or mitigate PM-10 emissions.

B. Applicability

This rule applies to any new or existing public or private Paved or Unpaved Road, road 

construction project, or road modification project. 

C. Definitions

The definitions of terms found in Rule 800 (General Requirements for Control of Fine 

Particulate Matter (PM-10) shall apply to this rule.

D. Exemptions

In addition to the exemptions listed in Rule 800, Section E, the following exemptions are 

established for this Rule:

D.1 Paved and unpaved driveways serving one single family residential dwelling.

D.2 Agricultural Operation Sites defined in and subject to Rule 806, Conservation 

Management Practices.

D.3 Recreational OHV Use Areas on public lands subject to Rule 800, General 

Requirements for Control of Fine Particulate Matter (PM-10).

E. Requirements

E.1 Unpaved Haul/Access Roads: No Person shall cause, suffer or allow the 

operation, use, or maintenance of any unpaved Haul/Access Road without 

complying with one or more of the requirements of Section F.1 so as to limit VDE 

to 20% opacity.

E.2 Unpaved Roads: On any Unpaved Road segment with 50 or more Average

Vehicle Trips per Day, the owner/operator shall limit VDE to 20% opacity, as 

determined by the test methods for “Visual Determination of Opacity” in Rule 

800, Appendix A, and comply with the requirements of a Stabilized Unpaved 

Road by application and/or maintenance of at least one of the requirements of 

Section F.1.
Imperial County Air Pollution Control District Rule 805

Imperial County Rule 805, Final Settlement, June 20, 2012

E.3 The construction of any new Unpaved Road is prohibited within any area with a 

population of 500 or more unless the road meets the definition of a Temporary 

Unpaved Road. The Temporary Unpaved Road shall meet the definition of a 

Stabilized Unpaved Road as determined by the test methods in Rule 800, 

Appendix B, Section C, and where VDE is limited to 20% opacity. 

E.4 Canal Roads: all Persons who cause, suffer or allow the operation, use or 

maintenance of any Canal Road with 20 or more Average Vehicle Trips per Day 

shall comply with one or more of the requirements of Section F.1 to comply with 

the requirements of a Stabilized Unpaved Road and limit VDE to 20% opacity, as 

determined by the test methods in Rule 800, Appendix A, and shall also comply 

with one or more of the requirements of Section F.2.

E.5 Unpaved Traffic Areas: All Persons who cause, suffer or allow the operation, use 

or maintenance of any Unpaved Traffic Area larger than one (1) acre and with 75 

or more Average Vehicle Trips per Day shall comply with one or more of the 

requirements of Section F.3 and limit VDE to 20% opacity.

E.6 Paved Roads: any new or Modified Paved Roads shall comply with the 

requirements of section F.4. 

E.7 Requirements for Existing Unpaved Public Roads in City and Rural Areas:

Each city or county agency with primary responsibility for any existing Unpaved 

Road shall take the following actions:

E.7.a By January 1, 2006 provide the APCD with a list of all Unpaved Roads 

under its jurisdiction in any city or Rural area(s), including data on length

of, and Average Vehicle Trips per Day on, each Unpaved Road segment.

E.7.b By March 31, 2006 the County Public Works Department shall provide 

the APCD and comply with a compliance plan. The compliance plan shall 

include a compliance schedule indicating that during the period 2006 

through 2015 a 10% per each fiscal year, beginning July 1 and ending 

June 30, of all Unpaved Roads subject to the requirements of this rule will 

comply with a 20% VDE and comply with the requirements of a 

Stabilized Unpaved Road (Treatment in excess of the annual requirement 

can be credited toward future year requirements). The plan shall identify 

the control measures implemented or that will be implemented at each 

Unpaved Road segment with 50 or more Average Vehicle Trips per Day.

The plan shall clarify that the 10% stabilized each year differ from the 

roads previously stabilized so that 100% of roads are stabilized by 2015.

E.7.c By July 31 of each year, 2007 through 2016, the County Public Works 

Department shall submit to the APCD the total number of Unpaved Road 
Imperial County Air Pollution Control District Rule 805

Imperial County Rule 805, Final Settlement, June 20, 2012

miles which were mitigated during the previous fiscal year, a list of the 

specific mitigated roads, and the percentage of cumulative miles relative 

to the schedule provided pursuant to Section E.7.b. Once stabilized 

pursuant to Section E.7, Public Roads must comply with the requirements 

of a Stabilized Unpaved Road by application and/or maintenance of at 

least one of the requirements of Section F.1.

F. Best Available Control Measures for Fugitive Dust (PM-10)

F.1 UNPAVED ROADS, INCLUDING UNPAVED HAUL AND ACCESS ROADS:

F.1.a Pave.

F.1.b Apply Chemical Stabilization as directed by product manufacturer to 

control dust on Unpaved Roads. 

F.1.c Apply and maintain Gravel, recrushed/recycled asphalt or other material 

of low Silt (<5%) content to a depth of three or more inches. 

F.1.d Wetting. Apply water one or more times daily

F.1.e Permanent road closure

F.1.f Restrict unauthorized vehicle access.

F.1.g Any other method that effectively limits VDE to 20% opacity and meets 

the conditions of a Stabilized Unpaved Road.

F.2 CANAL ROADS:

F.2.a Stocking of Triploid Grass Carp in canals to reduce maintenance vehicle 

trips along Canal Banks to mechanically remove aquatic weeds.

F.2.b Installation of remote control delivery gates to eliminate manual gate 

operation by maintenance personnel in vehicles along Canal Banks.

F.2. c Implement Silt removal program to delay grading of spoil piles deposited 

on Canal Bank after cleaning operations until the next cleaning operation 

to eliminate vehicle access to Canal Bank.

F.2.d Permanent road closure.

F.2.e Conversion of open canals to pipeline.

F.2.f Lining canals to eliminate maintenance for Silt/weed control.
Imperial County Air Pollution Control District Rule 805

Imperial County Rule 805, Final Settlement, June 20, 2012

F.2.g Canal Bank surface maintenance.

F.3 UNPAVED TRAFFIC AREAS:

F.3.a Pave.

F.3.b Apply Chemical Stabilization as directed by product manufacturer to 

control dust on Unpaved Roads.

F.3.c Apply and maintain Gravel, recrushed/recycled asphalt or other material 

of low silt (<5%) content to a depth of three or more inches.

F.3.d Wetting. Apply water one or more times daily.

F.4. NEW OR MODIFIED PAVED ROADS

Any Person having jurisdiction over, or ownership of, public or private Paved 

Roads shall construct, or require to be constructed, all new or Modified Paved 

Roads in conformance with the Imperial County Public Works Department

guidelines for width of shoulders and median shoulders as specified below:

F.4.a New arterial roads or streets or modifications to existing arterial roads or 

streets shall be constructed with paved shoulders that meet following 

widths:

Annual Average Daily 

Vehicle Trips

Minimum Paved or Stabilized 

Shoulder Width in Feet

 1-2000 2

 Greater than 2000 6

F.4.b New or modified collector roads or streets or local roads or streets shall be 

constructed with paved shoulders that meet following widths:

Annual Average Daily 

Vehicle Trips

Minimum Paved or Stabilized 

Shoulder Width in Feet

 1-2000 2

 Greater than 2000 4

F.4.c A curbing adjacent to and contiguous with the travel lane or paved 

shoulder or a road may be constructed, in lieu of meeting the paved 

shoulder width standard listed in Sections F.4.a and F.4.b. Any road 

paving projects constructing curbing in County road right of ways shall be 

approved by the Director of Public Works Department prior to 

construction. 

F.4.d Intersections, auxiliary entry lanes, and auxiliary exit lanes may be 
Imperial County Air Pollution Control District Rule 805

Imperial County Rule 805, Final Settlement, June 20, 2012

constructed adjacent to and contiguous with the roadway, in lieu of 

meeting the paved shoulder width standard in Sections F.4.a and F.4.b. 

F.4.e New Paved Road construction or modifications to an existing Paved Road 

that are required to comply with California Environmental Quality Act 

(CEQA) and National Environmental Policy Act (NEPA) determinations 

regarding environmental, cultural, archeological, historical, or other 

considerations addressed in such documents, are exempt from the paved 

shoulder width requirements specified in Section F.4.a.

F.4.f Whenever any Paved Road which has projected Annual Average Daily 

Vehicle Trips of 500 or more is constructed, or modified with medians, the 

medians shall be constructed with paved shoulders having a minimum 

width of four feet adjacent to the traffic lanes unless:

F.4.f1 The medians of roads having speed limits set at or below 45 miles 

per hour are constructed with curbing; or 

F.4.f2 The medians are landscaped and maintained with grass or other 

vegetative ground cover to comply with the definition of Stabilized 

Surface.

F.4.g In lieu of complying with the paving or vegetation requirements a Person 

may apply oils or other Chemical Stabilizers/Suppressants to the required 

width of shoulder and median areas as specified in Sections F.4.a and 

F.4.b. The material shall be reapplied and maintained to limit VDE to 20% 

opacity and fulfill conditions for a Stabilized Surface.

G. Record of Control Implementation

Any Person subject to the requirements of this rule shall compile and retain records that 

provide evidence of control measure application (i.e., receipts and/or purchase records). 

Such Person shall describe, in the records, the type of treatment or control measure, 

extent of coverage, and date applied. For control measures which require multiple daily 

applications, recording the frequency of application will fulfill the recordkeeping 

requirements of this rule (i.e., water being applied three times a day and the date) Records 

shall be maintained and be readily accessible for two years after the date of each entry 

and shall be provided to the APCD upon request. 

H. Violations

Failure to comply with any provisions of this rule shall constitute a violation of 

Regulation VIII. 
Imperial County Air Pollution Control District Rule 806 

RULE 806 CONSERVATION MANAGEMENT PRACTICES

(Adopted 11/08/2005; Revised XX/XX/XXXX)

A. Purpose

The purpose of this regulation is to reduce the amount of coarse fine Particulate 

Matter (PM-10) entrained in the ambient air as a result of emissions generated 

from Agricultural Operation Sites by requiring Conservation Management 

Practices to prevent, reduce, or mitigate PM-10 emissions.

B. Applicability

This rule applies to Agricultural Operation Sites located within the Imperial 

County. Effective on and after XXXX January 1, 2006, an owner/operator shall 

implement the applicable CMPs selected for each Agricultural Operation Site.

C. Definitions

In addition to the definitions of terms in Rule 800 (General Requirements for 

Control of Fine Particulate Matter (PM-10), the following definitions shall govern 

the implementation of this rule: 

C.1 AGRICULTURAL OPERATIONS: The growing and harvesting of crops for 

the primary purpose of earning a living.

C.2 AGRICULTURAL OPERATION SITE: One or more agricultural parcels 

that meet the following:

C.2.a Are under the same or common ownership or operation, or which 

are owned or operated by entities which are under common control; 

and

C.2.b Are located on one or more contiguous or adjacent properties 

wholly within Imperial County.

C.3 AGRICULTURAL PARCEL: A portion of real property used by an owner 

or operator for carrying out a specific agricultural operation. Roads, 

vehicle/equipment traffic areas, and facilities, on or adjacent to the 

cropland are part of the agricultural parcel.

C.4 ALTERNATIVE TILLING: Rotate tillage leaving residue on soil. Tilling

alternative rows for weed management, reducing and wind blown dust 

allows for approximately 50% of reduction in field activity related to tilling,

in addition to stabilizing soil surface and reducing soil compaction.

C.5 APPLICATION EFFICIENCIES: Use more efficient application equipment 

so as to reduce a minimum of one ground operation. Examples include: 

compact or low volume spray equipment; aerial applications; micro-heads 

or infrared spot sprayers; electrostatic sprayers. Reduces soil compaction, 

passes and chemical usage.
Imperial County Air Pollution Control District Rule 806 

C.65 BALING/LARGE BALES: Reduce a minimum of one pass through the field 

per acre by using large balers to harvest crops. Using balers to harvest 

crop. It reduces PM emissions from crops traditionally harvested by 

chopping, truck, passes and residue burning.

C.76 BED/ROW SIZE OR SPACING: Reduce a minimum of one tillage 

operation by Increasinge or decreasinge the size of the planting bed area 

(can be done for field and permanent crops) or adjusting spacing. 

Spacing adjustments reduce the number of passes and soil disturbance 

by increasing plant density/canopy through reduction of row width to 

contain PM within the canopy.

C.8 BULK MATERIALS CONTROL: Minimize visible dust emissions from bulk 

materials by using dust suppressant or water to form a stabilized surface, 

or using a tarp to fully cover the pile or truckbed, or using a wind barrier or 

3-sided structure to reduce entrainment of fugitive dust.

C.97 CHEMIGATION/FERTIGATION: Reduce a minimum of one ground 

operation by applying Application of chemicals through an irrigation 

system. This Each application reduces the need to travel in the field for 

application purposes, thus reducing operations the number of passes and 

soil disturbance while increasing the efficiency of the application.

C.108 CHIPS/MULCHES, ORGANIC MATERIALS, POLYMERS, ROAD OIL & 

SAND: Application of any nontoxic chemical or organic dust suppressant 

that meets all specification required by any federal, state, or local water 

agency and is not prohibited for use by any applicable regulations.

Chips/Mulches and organic materials should meet the specifications in the 

mulches definition below. Polymers, road oil and sand should create a 

stabilized surface during high traffic times such as harvest.

C11.9 COMBINED OPERATION: To cCombine equipment to perform several 

operations during one pass, thereby reducing a minimum of one tillage 

operation. The reduction in the number of passes necessary to cultivate 

the land will result in fewer disturbances to the soil. Examples include: 

use of one-pass till equipment in ground preparation or crop tillage; and 

cultivation and fertilization of a field crop in a single pass. Other benefits 

are reduction of soil compaction and time to prepare fields, both of which 

can be precursors to additional tillage requirements. If a combined 

operation is accomplished through equipment change/technological 

improvement, that action is considered one CMP, and either Equipment 

Changes/Technological Improvements CMP or Combined Operations 

CMP may be selected in a CMP Plan, but not both. 

C.120 CONSERVATION IRRIGATION: Reduce a minimum of one tillage 

operation related to weeding by To conservinge the amount quantity of 

water used by using either, e.g.: drip, sprinkler, or buried/underground line

irrigation. Conserving water reduces weed population, which in turn 

reduces the need for tillage and as well as reduces soil compaction.
Imperial County Air Pollution Control District Rule 806 

C.131 CONSERVATION MANAGEMENT PRACTICE (CMP): An activity or 

procedure that prevents, reduces, or mitigates PM-10 normally emitted by, 

or associated with, an agricultural activity.

C.142 CONSERVATION MANAGEMENT PRACTICES PLAN (CMP PLAN): A 

document prepared by the owner or operator of an Agricultural Operation 

site that lists the selected CMPs for implementation. The CMP Plan also 

contains, but is not limited to, contact information for the owner or 

operator, a description of the Agricultural Operation Site and locations of 

Agricultural Parcels, and other information describing the extent and 

duration of CMP implementation.

C.153 CONSERVATION TILLAGE (e.g.: no tillage, minimum tillage): A tillage 

system that reduces a minimum of three tillage operations. This system 

reduces soil and water loss by reducing the number of passes and by 

leaving crop residue on the field after harvest as well as managing the 

residue so that it remains intact during the planting season. Types of 

tillage that reduce loss of soil and water in comparison to Conventional 

Tillage. It reduces the number of passes and amount of soil disturbance. 

It improves soil because it retains plant residue and increases organic 

matter.

C.164 COVER CROPS: Establish cover crops that maintain a minimum of 60 

percent ground cover, as determined by the line-intersection method. 

Native or volunteer vegetation that meets the minimum ground cover 

requirement is acceptable. Use seeding or natural vegetation/regrowth of 

plants to cover soil surface. It reduces soil disturbance due to wind erosion 

and entrainment.

C.17 CROP RESIDUE MANAGEMENT: Maintain crop residue from previous 

crops until tilling for the next crop. Crop residues must maintain a 

minimum of 60 percent ground cover as determined by line-intersection 

method. Implements such as undercuters or sweeps can maintain crop 

residues without burying or destroying residues.

C.18 CROPLAND - OTHER: This CMP category includes CMPs to reduce 

windblown emissions.

C.19 CROSS WIND STRIPCROPING: Establish crops in parallel strips across 

the prevailing wind erosion direction and arranged so that strips 

susceptible to wind erosion are alternated with strips having a protective 

cover that is resistant to wind erosion. The strips with the protective cover 

should be at least as wide as the strips susceptible to wind erosion.

C.2015EQUIPMENT CHANGES/TECHNOLOGICAL IMPROVEMENTS: To 

modify the equipment such as tilling; increase equipment size; modify land 

planting and land leveling; matching the equipment to row spacing; 

granting to new varieties or other technological improvements. It reduces 

the number of passes during an operation, thereby reducing soil 
Imperial County Air Pollution Control District Rule 806 

disturbance. Reduce a minimum of one tillage operation by modifying 

equipment or making technological improvements. Examples include 

flame cultivation or equipment that combines discing, chiseling and ring 

rolling. If an equipment change/technological improvement is made in 

order to combine operations, that action is considered one CMP; either 

Equipment Changes/Technological Improvements CMP or Combined 

Operations CMP may be selected in the CMP plan, but not both.

C.2116FALLOWING LAND: Temporary or permanent removal from production. 

Eliminates entire operation/passes or reduces activities.

C.22 FIELD WINDBREAKS: Plant or maintain a single or multiple row of trees 

or shrubs adjacent to windward edge of the field as close to perpendicular 

as practical with the direction of erosive winds. Windbreaks such as trees 

or shrubs should be established at a right angle to the prevailing wind 

direction. Sites downwind of the windbreak are considered protected if 

they fall within an area that is less than or equal to 10 times the height of 

the windbreak. The windbreak should have a porosity of 50 %. 

C.2317GRAVEL: Placing a layer of Gravel at least 3 inches in with enough depth 

to minimize dust generated from vehicle movement and to dislodge any 

excess debris which can become entrained. Gravel should conform to the 

grading defined in Rule 800.

C.2418GREEN CHOP: The Reduce a minimum of one ground operation by

harvesting of a forage crop without allowing it to dry in the field. It reduces 

multiple equipment passes in-field as well as. This practice reduces soil 

disturbance and soil compaction.

C.25 GRINDING/CHIPPING/SHREDDING: Grinding prunings and orchard 

removals instead of burning; incorporate to soil. Reduces PM from burning 

crop residues.

C.26 GROUND OPERATION: An agricultural operation that is not a tillage 

operation that involves equipment passing across the field, such as a 

chemical spray application. A pass through the field may be a subset of a 

ground operation. 

C.2719HAND HARVESTING: Reduce a minimum of one ground operation by

Hharvesting a crop by hand. It reduces soil disturbance due to machinery 

passes.

C.280 INTEGRATED PEST MANAGEMENT: Reduce a minimum of one ground 

operation by using A decision process that uses a combination of 

techniques including organic, conventional and biological farming 

concepts to suppress pest problems. It creates beneficial insect habitat 

that reduces the use of herbicides/pesticides thereby reducing number of 

passes for spraying. It also reduces soil compaction and the need for 

additional tillage. If integrated pest management CMP uses the same 

practices described in the Organic Practices CMP, this action is 
Imperial County Air Pollution Control District Rule 806 

considered one CMP, and either Integrated Pest Management CMP or 

Organic Practices CMP may be selected in a CMP plan, but not both.

C.21 MECHANICAL PRUNING: Using a machine instead of hand labor to 

prune (Applies as an Unpaved Road CMP only). It reduces vehicle trips, 

thereby reducing PM emissions. 

C.29 IRRIGATION POWER UNITS: Use cleaner burning engines, electric 

motors (CMP only applicable if engines are cleaner than otherwise 

required by current local, state and federal requirements). 

C.3022MULCHING: Reducing PM10 emissions and wind erosion and preserving 

soil moisture by uniformly applying a protective layer of plant residue or 

other material to a soil surface prior to disturbing the site to reduce soil 

movement. Mulching material shall be evenly applied, and if necessary, 

anchored to the soil. Mulch should achieve a minimum 70% cover, and a 

minimum of 2 inch height above the surface. Inorganic material used for 

mulching should consist of pieces of .75 to 2 inches in diameter. Applying 

or leaving plant residue or other material to soil surface. It reduces 

entrainment of PM due to winds as well as reduces weed competition 

thereby reducing tillage passes and compaction.

C.231 NIGHT FARMING: Operate at night, if practical, when moisture levels are 

higher and winds are lighter. It decreases the concentration of PM 

emissions during daytime and the increased ambient humidity reduces PM 

emissions during the night. Night farming should take place between 

sundown and sunrise.

C.324 NIGHT HARVESTING: Implementing harvesting cultural practices at night

when moisture levels are higher and winds are lighter. , or at times or high 

humidity. It reduces PM by operating when ambient air is moist, thereby 

reducing PM emissions. Night harvesting should take place between 

sundown and sunrise.

C.3325NO BURNING: Switching to a crop/system that would not require waste 

burning. It reduces emissions associated with burning.

C.3426NON TILLAGE/CHEMICAL TILLAGE: Reduce a minimum of one tillage 

operation by, for example, Use using a flail mower or low volume sprayers 

or heat delivery systems (as harvest pre-conditioner). It reduces soil 

compaction and stabilizes soil through elimination or reduction of soil 

tillage passes. 

C.3527ORGANIC PRACTICES PESTICIDES: Reduce a minimum of one ground 

or tillage operation by using Use biological control methods or nonchemical control methods. It reduces chemical use, thereby reducing 

passes. Examples include: organic certification, biological controls, 

mulches and humus. If an organic practice CMP uses the same practice 

as described in the integrated pest management CMP, this action is 
Imperial County Air Pollution Control District Rule 806 

considered one CMP, and either Organic Practices CMP or Integrated 

Pest Management CMP may be selected in a CMP plan, but not both.

C.3628PAVING: To pave currently Unpaved Roads.

C.37 PERMANENT CROPS: Having an established permanent crop that is not 

replanted annually.

C.3829PRECISION FARMING (GPS): Reduce a minimum of one pass through 

the field per acre by Uusing satellite navigation to calculate position in the 

field, therefore manage/treat the selective area. It reduces overlap and 

allows operations to occur during inclement weather conditions and at 

night thereby generating less PM.

C.3930PRE-HARVEST SOIL PREPARATION: Applying a light amount of water 

or stabilizing material to soil prior to harvest (when possible) to form a 

visible crust. It reduces PM emissions at harvest.

C.40 REDUCED PRUNING: Reduce a minimum of one ground operation by 

reducing the frequency of pruning (e.g. one time per year, or every other 

year).

C.431 RESTRICTED ACCESS: To restrict or eliminate public access to unpaved 

private roads with signs or physical obstructions. At each access point, 

install signs or physical barriers such as gates, fencing, posts, signs, 

shrubs, trees that block or effectively control access to the area. It reduces 

vehicle traffic and thus reduces associated fugitive dust.

C.42 RIDGE ROUGHNESS: Establish stabilized ridges by normal tillage and 

planting equipment as close to perpendicular as practical with the direction 

of erosive winds (not appropriate for unstable soils such as sands or 

loamy sands). After establishment, ridges shall be maintained through 

those periods when wind erosion is expected to occur, or until growing 

crops provide enough cover to protect the soil from wind erosion. Ridge 

spacing should be no greater than 4 times the ridge height.

C.43 ROAD MIX: A mixture of tank bottoms from crude oil storage tanks, 

material from crude oil spills, or other crude-oil-containing soil mixed with 

aggregates and soils, that are used as a base cover materials for roads, 

parking lots, berms, tank and well locations, or similar applications.

C.4432SHED PACKING: Reducing a minimum of one pass through the field per 

acre by Ppacking commodities in a covered or closed area, rather than 

field-pack. It reduces field traffic, thereby reducing PM emissions.

C.4533SHUTTLE SYSTEM/LARGE CARRIER: Multiple bin/trailer. Reduce a 

minimum of one pass through the field per acre by Hhauling multiple or 

larger trailers/bins per trip thereby reducing emissions through reduced 

passes.
Imperial County Air Pollution Control District Rule 806 

C.46 SOIL AMENDMENTS: Organic or chemical materials uniformly applied to 

the soil for improvement (e.g: gypsum, lime, polyacrylamide).

C.4734SPEED LIMITS: Control speed limits to 15 mph on unpaved roads 

through worker behavior modifications, signage, or any other necessary 

means. Enforcement of speeds that reduce visible dust emissions. The 

dust emissions from unpaved roads are a function of speed meaning 

reducing speed reduces dust.

C.48 SULFUR REDUCTION OR ELIMINATION: Reduce a minimum of one 

ground operation by reducing or eliminating sulfur dusting, an organic 

chemical used to control disease in crop, ornamental and home and 

gardens.

C.49 SURFACE ROUGHENING: Produce and maintain stable clods or 

aggregates on the land surface by bedding, rough disking, or tillage that 

leaves the surface covered by stable clods. Soil clods prevent wind 

erosion because they resist the forces of the wind and because they 

shelter other erodible materials. This CMP should be implemented 

consistent with NRCS Code 609 – Surface Roughening.

C.50 TILLAGE OPERATION: An agricultural operation that mechanically 

manipulates the soil for the enhancement of crop production. Examples 

include discing, weeding, or bedding. A pass through the field may be a 

subset of a tillage operation.

C.351 TRACK-OUT CONTROL: Minimize any and all material that adheres to 

and agglomerates on all vehicle and equipment from unpaved roads and 

falls onto a paved public road or the paved shoulder of a paved public 

road. Install one of the following devices: a grizzly, a gravel pad or a 

wheelwash system at all intersections of unpaved roads and public roads.

C.5236TRANSGENIC CROPS: Use of GMO or Transgenic crops such as 

“herbicide-ready” to reduce a minimum of one tillage operation. It reduces 

the need for tillage or cultivation operations, as well as reduces soil 

disturbance. It can also reduce the number of chemical applications.

C.537WATER APPLICATION: Application of water to unpaved roads and traffic 

areas to create a visibly moist surface.

C.5438WIND BARRIER: Reduce wind erosion by planting or maintaining 

perennial or annual plants established in rows or narrow strips 

interspersed throughout a crop field as close to perpendicular as practical 

with the direction of erosive winds. To be effective, the selected plant(s) 

must create a stand at least three feet tall, with a porosity of 50%. Artificial 

or vegetative wall/fence that disrupts the erosive flow of wind over 

unprotected land.
Imperial County Air Pollution Control District Rule 806 

D. Requirements for Agricultural Operation Sites:

D.1 All Persons who own or operate an Agricultural Operation Site of forty (40) 

acres or more in size shall implement in each Agricultural Parcel at least 

one of the Conservation Management Practices listed in Section E.1 for 

each of the following categories: from each of D.1.a through D.1.f. unless 

they implement the Conservation Tillage CMP. On acres implementing 

the Conservation Tillage CMP, persons do not need to select additional 

measures for D.1.a, D.1.b or D.1.e, but do need to implement at least one 

CMP each from D.1.c, D.1.d and D.1.f. Persons may choose the same 

CMP for D.1.c and D.1.d since they apply to different land, but must 

choose a unique and individual CMP for each of D.1.a, D.1.b, D.1.e and 

D.1.f (unless using Conservation Tillage CMP) since they apply to the 

same land.

D.1a Land preparation and cultivation, CMPs in Section E.1;

D.1.b Harvest activities, CMPs in section E.2; 

D.1.c Unpaved Roads, CMPs in Section E.3;

D.1.d Unpaved Traffic Areas, CMPs in Section E.4;

D.1.e Cropland-Other CMPs, in Section E.5; and

D.1.f Windblown Dust Control CMPs in Section E.6.

D.2 Agricultural unpaved roads with greater than fifty (50) or more vehicle daily 

trips (VDT), or twenty (20) or more VDT with three (3) or more axle 

vehicles, must meet the stabilization and opacity requirements in Section 

E.3.

D.3 Agricultural unpaved equipment or traffic areas with fifty (50) or more VDT, 

or twenty (20) or more VDT with 3 or more axle vehicles, must meet the 

stabilization and opacity requirements in Section E.4.

D.42 The owner or operator of an Agricultural Operation Site may implement 

more than one Conservation Management Practices for one or more of 

the categories.

D.53 The owner or operator of an Agricultural Operation Site shall ensure that 

the implementation of each selected Conservation Management Practices 

does not violate any other local, state, or federal law.

D.64 The owner or operator of an Agricultural Operation Site may develop 

alternative CMPs. The owner or operator shall submit to the APCD a 

technical evaluation of the alternative CMPs, demonstrating that the 

alternative CMP achieves PM-10 emission reductions that are at least 

equivalent to other CMPs available for the applicable operation. The 

APCD will review the technical evaluation, and the alternative CMP must 
Imperial County Air Pollution Control District Rule 806 

receive approval by the APCD before being included in the CMP Plan. 

D.75 The owner or operator shall prepare a CMP Plan for each Agricultural 

Operation Site. The CMP Plan shall be made available to the APCD upon 

request. The CMP Plan shall be provided to the APCD within 72 hours of 

notice to the owner or operator. 

E. Conservation Management Practices for Fugitive Dust (PM-10)

E.1 The owner or operator of an Agricultural Operation Site shall implement at 

least one of the following CMPs in each Agricultural Parcel to reduce 

PM10 emissions from land preparation and cultivation (CMP Category 

D.1.a). If the owner or operator selects “Fallow Land” as its CMP, the 

owner/operator must comply with section E.6 of this rule. 

E.1.a Alternateive Tilling,

E.1.b Bed/Row Size Spacing, 

E.1.c Chemicalgation/Fertigation,

E.1.d Combined Operations,

E.1.e Conservation Irrigation,

E.1.f Conservation Tillage,

E.1.fg Cover Crops,

E.1.ghEquipment Changes/Technological Improvements,

E.1.hi Fallowing Land,

E.1.ij Integrated Pest Control,

E.1.jk Mulching,

E.1.kl Night Farming,

E.1.lm Non Tillage /Chemical Tillage,

E.1.mnOrganic Pesticides,

E.1.noPrecision Farming (GPS), or

E.1.opTransgenic Crops

E.2 The owner or operator of an Agricultural Operation Site shall implement at 

least one of the following CMPs in each Agricultural Parcel to reduce 

PM10 emissions from harvesting activities (CMP Category D.1.b). : If the 

owner or operator selects “Fallow Land” as its CMP, the owner/operator 

must comply with Section E.6 of this rule. 

E.2.a Baling /Large Bales

E.2.b Combined Operations

E.2.c Equipment Changes/Technological Improvements

E.2.d Green Chop

E.2.e Hand Harvesting

E.2.f Fallowing Land

E.2.g Night Harvesting

E.2.h No Burning

E.2.i Pre-Harvesting Soil Preparation

E.2.j Shed Packing
Imperial County Air Pollution Control District Rule 806 

E.2.k Shuttle System/Large Carrier

E.3 The owner or operator of an Agricultural Operation Site shall implement at 

least one of the following CMPs for each Uunpaved Rroad (CMP Category 

D.1.c) to reduce PM10 emissions at all times:

E.3.a Chips/Mulches, Organic Materials, polymers, road oil and sand,

E.3.b Gravel

E.3.c Paving,

E.3.d Restricted access

E.3.e Speed limit

E.3.f Track-out control

E.3.g Water Application

E.3.h Wind barrier Field windbreak

On each day that high traffic accounts for 50 or more vehicle daily trips 

(VDT), or 20 or more VDT with 3 or more axles, on an unpaved road 

segment, the owner/operator of an Agricultural Operation Site shall 

comply with the requirements of a stabilized unpaved road and limit VDE 

to 20% opacity by implementing or maintaining one or more of the 

following CMPs:

E.3.i Pave.

E.3.j Apply Chemical Stabilization as directed by product manufacturer 

to control dust on Unpaved Roads. 

E.3.k Apply and maintain Gravel, recrushed/recycled asphalt or other 

material of low Silt (<5%) content to a depth of three or more 

inches. 

E.3.l Water Application.

E.3.m Permanent road closure.

E.3.n Restrict unauthorized vehicle access.

E.4 The owner or operator of an agricultural operation site shall implement at 

least one of the following CMPs for each unpaved traffic area (CMP 

Category D.1.d) to reduce PM10 emissions at all times:

E.4.a Chips/Mulches, Organic Materials, Polymers, Road Oil and Sand,

E.4.b Gravel

E.4.c Paving

E.4.d Restricted Access

E.4.e Speed Limit

E.4.f Track-Out Control

E.4.g Water Application

E.4.h Wind Barrier Field windbreak

On each day that high traffic accounts for 50 or more vehicle daily trips 

(VDT), or 20 or more VDT with 3 or more axles, on an Unpaved Traffic 

Area larger than one (1) acre, the owner/operator of an Agricultural 

Operation Site shall comply with the requirements of a stabilized unpaved 

road and limit VDE to 20% opacity by implementing or maintaining one or 
Imperial County Air Pollution Control District Rule 806 

more of the following CMPs:

E.4.i Pave.

E.4.j Apply Chemical Stabilization as directed by product manufacturer 

to control dust on Unpaved Roads. 

E.4.k Apply and maintain Gravel, recrushed/recycled asphalt or other 

material of low Silt (<5%) content to a depth of three or more 

inches. 

E.4.l Water Application.

E.5 The owner or operator of an Agricultural Operation Site shall implement at 

least one of the following CMPs in each Agricultural Parcel to reduce 

PM10 emissions from cropland-others (Category D.1.e). If the owner or 

operator selects “Fallow Land” as its CMP, the owner/operator must 

comply with Section E.6 of this rule. 

E.5.a Alternate Tilling

E.5.b Application Efficiencies

E.5.c Bailing/Large Bales

E.5.d Bulk Materials Control

E.5.e Chemigation/Fertigation

E.5.f Conservation Irrigation

E.5.g Fallow Land

E.5.h Grinding/Chipping/Shredding

E.5.i Integrated Pest Management

E.5.j Irrigation Power Units

E.5.k Mulching

E.5.l Night Farming

E.5.m No Burning

E.5.o Non Tillage/Chemical Tillage

E.5.p Organic Practices

E.5.q Permanent Crops

E.5.r Reduced Pruning

E.5.s Soil Amendments

E.5.t Soil Incorporation

E.5.u Sulfur: Reduction or Elimination of Dusting

E.5.v Surface Roughening

E.5.w Transgenic Crops

E.5.x Wind Barrier

E.6 For windblown dust control (CMP Category D.1.f), the owner or operator 

of an agricultural operation site shall implement E.6.1. In addition to 

following E.6.1, if the owner or operator of an Agricultural Operation Site 

has fields that are in between crops or more permanently fallow, the 

owner or operator shall implement at least one of the CMPs in E.6.2.

E.6.1 When preparing a field for planting, minimize the time that newly 

tilled soil is smooth and dry by leaving the field surface with large 

clods for as long as possible and bedding and planting the field as 

soon as possible once it no longer has large clods. 
Imperial County Air Pollution Control District Rule 806 

E.6.2 For fields that are in between crops or are permanently fallow, the 

owner shall implement at least one of the CMPs below: 

E.6.2.a Cover Crop

E.6.2.b Conservation Tillage

E.6.2.c Crop Residue Management

E.6.2.d Cross Wind Stripcropping

E.6.2.e Field Windbreaks

E.6.2.f Ridge Roughness

E.6.2.g Surface Roughening

E.6.2.h Wind Barrier

F. CMP Plan Preparation

An owner or operator shall prepare a CMP Plan for each Agricultural Operation 

Site. An owner or operator must maintain a CMP Plan that corresponds to the 

current crops being grown in the field and the corresponding CMPs for those 

crops. Each CMP Plan shall include, but is not limited to, the following 

information:

F.1 The name, business address, and telephone number of the owner or 

operator responsible for the preparation and implementation of the CMP 

Plan.

F.2 The signature of the owner or operator and the date that the CPM Plan 

was signed.

F.3 The location of the Agricultural Operation Site: cross roads; canal and 

gate number.

F.4 The crop grown at each location covered by the CMP Plan, total acreage 

for each crop, the length (miles) of unpaved roads, and the total area 

(acres or square feet) of the unpaved equipment and traffic areas to be 

covered by the CMP Plan, and.

F.5 The CMPs being implemented or planned for implementation for each 

crop, unpaved road, unpaved equipment and traffic area, and windblown 

dust control. The CMPs implemented should be described to verify that 

implementation is consistent with the CMP definitions in this rule.

F.6 Other relevant information as determined by the APCD.

G. Violations

Failure to comply with any provisions of this rule shall constitute a violation of 

Regulation VIII. Failure to comply with the provisions of a CMP Plan shall also 

constitute a violation of Regulation VIII.

H. Record of Control Implementation
Imperial County Air Pollution Control District Rule 806 

Any Person subject to the requirements of this rule shall maintain a copy of the 

CMP Plan and any supporting documentation necessary to confirm 

implementation of the CMPs. An owner or operator implementing alterative 

CMPs shall maintain a copy of technical evaluation for alternative CMPs and

documentation of APCD approval of alternative CMPs. Records shall be 

maintained for two years after the date of each entry and shall be provided to the 

APCD upon request.