403 - 1 

(Adopted May 7, 1976) (Amended November 6, 1992) 

(Amended July 9, 1993) (Amended February 14, 1997) 

(Amended December 11, 1998)(Amended April 2, 2004) 

(Amended June 3, 2005) 

RULE 403. FUGITIVE DUST

(a) Purpose 

The purpose of this Rule is to reduce the amount of particulate matter entrained in 

the ambient air as a result of anthropogenic (man-made) fugitive dust sources by 

requiring actions to prevent, reduce or mitigate fugitive dust emissions. 

(b) Applicability 

The provisions of this Rule shall apply to any activity or man-made condition 

capable of generating fugitive dust. 

(c) Definitions 

(1) ACTIVE OPERATIONS means any source capable of generating fugitive 

dust, including, but not limited to, earth-moving activities, 

construction/demolition activities, disturbed surface area, or heavy- and 

light-duty vehicular movement. 

(2) AGGREGATE-RELATED PLANTS are defined as facilities that produce 

and / or mix sand and gravel and crushed stone. 

(3) AGRICULTURAL HANDBOOK means the region-specific guidance 

document that has been approved by the Governing Board or hereafter 

approved by the Executive Officer and the U.S. EPA. For the South Coast 

Air Basin, the Board-approved region-specific guidance document is the 

Rule 403 Agricultural Handbook dated December 1998. For the 

Coachella Valley, the Board-approved region-specific guidance document 

is the Rule 403 Coachella Valley Agricultural Handbook dated April 2, 

2004. 

(4) ANEMOMETERS are devices used to measure wind speed and direction 

in accordance with the performance standards, and maintenance and 

calibration criteria as contained in the most recent Rule 403 

Implementation Handbook. 

(5) BEST AVAILABLE CONTROL MEASURES means fugitive dust 

control actions that are set forth in Table 1 of this Rule. 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 2 

(6) BULK MATERIAL is sand, gravel, soil, aggregate material less than two 

inches in length or diameter, and other organic or inorganic particulate 

matter. 

(7) CEMENT MANUFACTURING FACILITY is any facility that has a 

cement kiln at the facility. 

(8) CHEMICAL STABILIZERS are any non-toxic chemical dust suppressant 

which must not be used if prohibited for use by the Regional Water 

Quality Control Boards, the California Air Resources Board, the U.S. 

Environmental Protection Agency (U.S. EPA), or any applicable law, rule 

or regulation. The chemical stabilizers shall meet any specifications, 

criteria, or tests required by any federal, state, or local water agency. 

Unless otherwise indicated, the use of a non-toxic chemical stabilizer shall 

be of sufficient concentration and application frequency to maintain a 

stabilized surface. 

(9) COMMERCIAL POULTRY RANCH means any building, structure, 

enclosure, or premises where more than 100 fowl are kept or maintained 

for the primary purpose of producing eggs or meat for sale or other 

distribution. 

(10) CONFINED ANIMAL FACILITY means a source or group of sources of 

air pollution at an agricultural source for the raising of 3,360 or more fowl 

or 50 or more animals, including but not limited to, any structure, 

building, installation, farm, corral, coop, feed storage area, milking parlor, 

or system for the collection, storage, or distribution of solid and liquid 

manure; if domesticated animals, including horses, sheep, goats, swine, 

beef cattle, rabbits, chickens, turkeys, or ducks are corralled, penned, or 

otherwise caused to remain in restricted areas for commercial agricultural 

purposes and feeding is by means other than grazing. 

(11) CONSTRUCTION/DEMOLITION ACTIVITIES means any on-site 

mechanical activities conducted in preparation of, or related to, the 

building, alteration, rehabilitation, demolition or improvement of property, 

including, but not limited to the following activities: grading, excavation, 

loading, crushing, cutting, planing, shaping or ground breaking. 

(12) CONTRACTOR means any person who has a contractual arrangement to 

conduct an active operation for another person. 

(13) DAIRY FARM is an operation on a property, or set of properties that are 

contiguous or separated only by a public right-of-way, that raises cows or 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 3 

produces milk from cows for the purpose of making a profit or for a 

livelihood. Heifer and calf farms are dairy farms. 

(14) DISTURBED SURFACE AREA means a portion of the earth's surface 

which has been physically moved, uncovered, destabilized, or otherwise 

modified from its undisturbed natural soil condition, thereby increasing 

the potential for emission of fugitive dust. This definition excludes those 

areas which have: 

(A) been restored to a natural state, such that the vegetative ground 

cover and soil characteristics are similar to adjacent or nearby 

natural conditions; 

(B) been paved or otherwise covered by a permanent structure; or 

(C) sustained a vegetative ground cover of at least 70 percent of the 

native cover for a particular area for at least 30 days. 

(15) DUST SUPPRESSANTS are water, hygroscopic materials, or non-toxic 

chemical stabilizers used as a treatment material to reduce fugitive dust 

emissions. 

(16) EARTH-MOVING ACTIVITIES means the use of any equipment for any 

activity where soil is being moved or uncovered, and shall include, but not 

be limited to the following: grading, earth cutting and filling operations, 

loading or unloading of dirt or bulk materials, adding to or removing from 

open storage piles of bulk materials, landfill operations, weed abatement 

through disking, and soil mulching. 

(17) DUST CONTROL SUPERVISOR means a person with the authority to 

expeditiously employ sufficient dust mitigation measures to ensure 

compliance with all Rule 403 requirements at an active operation. 

(18) FUGITIVE DUST means any solid particulate matter that becomes 

airborne, other than that emitted from an exhaust stack, directly or 

indirectly as a result of the activities of any person. 

(19) HIGH WIND CONDITIONS means that instantaneous wind speeds 

exceed 25 miles per hour. 

(20) INACTIVE DISTURBED SURFACE AREA means any disturbed surface 

area upon which active operations have not occurred or are not expected to 

occur for a period of 20 consecutive days. 

(21) LARGE OPERATIONS means any active operations on property which 

contains 50 or more acres of disturbed surface area; or any earth-moving 

operation with a daily earth-moving or throughput volume of 3,850 cubic 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 4 

meters (5,000 cubic yards) or more three times during the most recent 

365-day period. 

(22) OPEN STORAGE PILE is any accumulation of bulk material, which is 

not fully enclosed, covered or chemically stabilized, and which attains a 

height of three feet or more and a total surface area of 150 or more square 

feet. 

(23) PARTICULATE MATTER means any material, except uncombined 

water, which exists in a finely divided form as a liquid or solid at standard 

conditions. 

(24) PAVED ROAD means a public or private improved street, highway, alley, 

public way, or easement that is covered by typical roadway materials, but 

excluding access roadways that connect a facility with a public paved 

roadway and are not open to through traffic. Public paved roads are those 

open to public access and that are owned by any federal, state, county, 

municipal or any other governmental or quasi-governmental agencies. 

Private paved roads are any paved roads not defined as public. 

(25) PM10 means particulate matter with an aerodynamic diameter smaller 

than or equal to 10 microns as measured by the applicable State and 

Federal reference test methods. 

(26) PROPERTY LINE means the boundaries of an area in which either a 

person causing the emission or a person allowing the emission has the 

legal use or possession of the property. Where such property is divided 

into one or more sub-tenancies, the property line(s) shall refer to the 

boundaries dividing the areas of all sub-tenancies. 

(27) RULE 403 IMPLEMENTATION HANDBOOK means a guidance 

document that has been approved by the Governing Board on April 2, 

2004 or hereafter approved by the Executive Officer and the U.S. EPA. 

(28) SERVICE ROADS are paved or unpaved roads that are used by one or 

more public agencies for inspection or maintenance of infrastructure and 

which are not typically used for construction-related activity. 

(29) SIMULTANEOUS SAMPLING means the operation of two PM10

samplers in such a manner that one sampler is started within five minutes 

of the other, and each sampler is operated for a consecutive period which 

must be not less than 290 minutes and not more than 310 minutes. 

(30) SOUTH COAST AIR BASIN means the non-desert portions of Los 

Angeles, Riverside, and San Bernardino counties and all of Orange 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 5 

County as defined in California Code of Regulations, Title 17, Section 

60104. The area is bounded on the west by the Pacific Ocean, on the 

north and east by the San Gabriel, San Bernardino, and San Jacinto 

Mountains, and on the south by the San Diego county line. 

(31) STABILIZED SURFACE means any previously disturbed surface area or 

open storage pile which, through the application of dust suppressants, 

shows visual or other evidence of surface crusting and is resistant to winddriven fugitive dust and is demonstrated to be stabilized. Stabilization can 

be demonstrated by one or more of the applicable test methods contained 

in the Rule 403 Implementation Handbook. 

(32) TRACK-OUT means any bulk material that adheres to and agglomerates 

on the exterior surface of motor vehicles, haul trucks, and equipment 

(including tires) that have been released onto a paved road and can be 

removed by a vacuum sweeper or a broom sweeper under normal 

operating conditions. 

(33) TYPICAL ROADWAY MATERIALS means concrete, asphaltic 

concrete, recycled asphalt, asphalt, or any other material of equivalent 

performance as determined by the Executive Officer, and the U.S. EPA. 

(34) UNPAVED ROADS means any unsealed or unpaved roads, equipment 

paths, or travel ways that are not covered by typical roadway materials. 

Public unpaved roads are any unpaved roadway owned by federal, state, 

county, municipal or other governmental or quasi-governmental agencies. 

Private unpaved roads are all other unpaved roadways not defined as 

public. 

(35) VISIBLE ROADWAY DUST means any sand, soil, dirt, or other solid 

particulate matter which is visible upon paved road surfaces and which 

can be removed by a vacuum sweeper or a broom sweeper under normal 

operating conditions. 

(36) WIND-DRIVEN FUGITIVE DUST means visible emissions from any 

disturbed surface area which is generated by wind action alone. 

(37) WIND GUST is the maximum instantaneous wind speed as measured by 

an anemometer. 

(d) Requirements 

(1) No person shall cause or allow the emissions of fugitive dust from any 

active operation, open storage pile, or disturbed surface area such that: 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 6 

(A) the dust remains visible in the atmosphere beyond the property line 

of the emission source; or 

(B) the dust emission exceeds 20 percent opacity (as determined by the 

appropriate test method included in the Rule 403 Implementation 

Handbook), if the dust emission is the result of movement of a 

motorized vehicle. 

(2) No person shall conduct active operations without utilizing the applicable 

best available control measures included in Table 1 of this Rule to 

minimize fugitive dust emissions from each fugitive dust source type 

within the active operation. 

(3) No person shall cause or allow PM10 levels to exceed 50 micrograms per 

cubic meter when determined, by simultaneous sampling, as the difference 

between upwind and downwind samples collected on high-volume 

particulate matter samplers or other U.S. EPA-approved equivalent 

method for PM10 monitoring. If sampling is conducted, samplers shall 

be: 

(A) Operated, maintained, and calibrated in accordance with 40 Code 

of Federal Regulations (CFR), Part 50, Appendix J, or appropriate 

U.S. EPA-published documents for U.S. EPA-approved equivalent 

method(s) for PM10. 

(B) Reasonably placed upwind and downwind of key activity areas and 

as close to the property line as feasible, such that other sources of 

fugitive dust between the sampler and the property line are 

minimized. 

(4) No person shall allow track-out to extend 25 feet or more in cumulative 

length from the point of origin from an active operation. Notwithstanding 

the preceding, all track-out from an active operation shall be removed at 

the conclusion of each workday or evening shift. 

(5) No person shall conduct an active operation with a disturbed surface area 

of five or more acres, or with a daily import or export of 100 cubic yards 

or more of bulk material without utilizing at least one of the measures 

listed in subparagraphs (d)(5)(A) through (d)(5)(E) at each vehicle egress 

from the site to a paved public road. 

(A) Install a pad consisting of washed gravel (minimum-size: one inch) 

maintained in a clean condition to a depth of at least six inches and 

extending at least 30 feet wide and at least 50 feet long. 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 7 

(B) Pave the surface extending at least 100 feet and at least 20 feet 

wide. 

(C) Utilize a wheel shaker/wheel spreading device consisting of raised 

dividers (rails, pipe, or grates) at least 24 feet long and 10 feet 

wide to remove bulk material from tires and vehicle undercarriages 

before vehicles exit the site. 

(D) Install and utilize a wheel washing system to remove bulk material 

from tires and vehicle undercarriages before vehicles exit the site. 

(E) Any other control measures approved by the Executive Officer and 

the U.S. EPA as equivalent to the actions specified in 

subparagraphs (d)(5)(A) through (d)(5)(D). 

(6) Beginning January 1, 2006, any person who operates or authorizes the 

operation of a confined animal facility subject to this Rule shall implement 

the applicable conservation management practices specified in Table 4 of 

this Rule. 

(e) Additional Requirements for Large Operations 

(1) Any person who conducts or authorizes the conducting of a large 

operation subject to this Rule shall implement the applicable actions 

specified in Table 2 of this Rule at all times and shall implement the 

applicable actions specified in Table 3 of this Rule when the applicable 

performance standards can not be met through use of Table 2 actions; and 

shall: 

(A) submit a fully executed Large Operation Notification (Form 403 

N) to the Executive Officer within 7 days of qualifying as a large 

operation; 

(B) include, as part of the notification, the name(s), address(es), and 

phone number(s) of the person(s) responsible for the submittal, and 

a description of the operation(s), including a map depicting the 

location of the site; 

(C) maintain daily records to document the specific dust control 

actions taken, maintain such records for a period of not less than 

three years; and make such records available to the Executive 

Officer upon request; 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 8 

(D) install and maintain project signage with project contact signage 

that meets the minimum standards of the Rule 403 Implementation 

Handbook, prior to initiating any earthmoving activities; 

(E) identify a dust control supervisor that: 

(i) is employed by or contracted with the property owner or 

developer; 

(ii) is on the site or available on-site within 30 minutes during 

working hours; 

(iii) has the authority to expeditiously employ sufficient dust 

mitigation measures to ensure compliance with all Rule 

requirements; 

(iv) has completed the AQMD Fugitive Dust Control Class and 

has been issued a valid Certificate of Completion for the 

class; and 

(F) notify the Executive Officer in writing within 30 days after the site 

no longer qualifies as a large operation as defined by paragraph 

(c)(18). 

(2) Any Large Operation Notification submitted to the Executive Officer or 

AQMD-approved dust control plan shall be valid for a period of one year 

from the date of written acceptance by the Executive Officer. Any Large 

Operation Notification accepted pursuant to paragraph (e)(1), excluding 

those submitted by aggregate-related plants and cement manufacturing 

facilities must be resubmitted annually by the person who conducts or 

authorizes the conducting of a large operation, at least 30 days prior to the 

expiration date, or the submittal shall no longer be valid as of the 

expiration date. If all fugitive dust sources and corresponding control 

measures or special circumstances remain identical to those identified in 

the previously accepted submittal or in an AQMD-approved dust control 

plan, the resubmittal may be a simple statement of no-change (Form 

403NC). 

(f) Compliance Schedule 

 The newly amended provisions of this Rule shall become effective upon adoption. 

Pursuant to subdivision (e), any existing site that qualifies as a large operation 

will have 60 days from the date of Rule adoption to comply with the notification 

and recordkeeping requirements for large operations. Any Large Operation 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 9 

Notification or AQMD-approved dust control plan which has been accepted prior 

to the date of adoption of these amendments shall remain in effect and the Large 

Operation Notification or AQMD-approved dust control plan annual resubmittal 

date shall be one year from adoption of this Rule amendment. 

(g) Exemptions 

(1) The provisions of this Rule shall not apply to: 

(A) Dairy farms. 

(B) Confined animal facilities provided that the combined disturbed 

surface area within one continuous property line is one acre or less. 

(C) Agricultural vegetative crop operations provided that the combined 

disturbed surface area within one continuous property line and not 

separated by a paved public road is 10 acres or less. 

(D) Agricultural vegetative crop operations within the South Coast Air 

Basin, whose combined disturbed surface area includes more than 

10 acres provided that the person responsible for such operations: 

(i) voluntarily implements the conservation management 

practices contained in the Rule 403 Agricultural Handbook; 

(ii) completes and maintains the self-monitoring form 

documenting sufficient conservation management 

practices, as described in the Rule 403 Agricultural 

Handbook; and 

(iii) makes the completed self-monitoring form available to the 

Executive Officer upon request. 

(E) Agricultural vegetative crop operations outside the South Coast Air 

Basin whose combined disturbed surface area includes more than 

10 acres provided that the person responsible for such operations: 

(i) voluntarily implements the conservation management 

practices contained in the Rule 403 Coachella Valley 

Agricultural Handbook; and 

(ii) completes and maintains the self-monitoring form 

documenting sufficient conservation management 

practices, as described in the Rule 403 Coachella Valley 

Agricultural Handbook; and 

(iii) makes the completed self-monitoring form available to the 

Executive Officer upon request. 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 10 

(F) Active operations conducted during emergency life-threatening 

situations, or in conjunction with any officially declared disaster or 

state of emergency. 

(G) Active operations conducted by essential service utilities to 

provide electricity, natural gas, telephone, water and sewer during 

periods of service outages and emergency disruptions. 

(H) Any contractor subsequent to the time the contract ends, provided 

that such contractor implemented the required control measures 

during the contractual period. 

(I) Any grading contractor, for a phase of active operations, 

subsequent to the contractual completion of that phase of earthmoving activities, provided that the required control measures have 

been implemented during the entire phase of earth-moving 

activities, through and including five days after the final grading 

inspection. 

(J) Weed abatement operations ordered by a county agricultural 

commissioner or any state, county, or municipal fire department, 

provided that: 

(i) mowing, cutting or other similar process is used which 

maintains weed stubble at least three inches above the soil; 

and 

(ii) any discing or similar operation which cuts into and 

disturbs the soil, where watering is used prior to initiation 

of these activities, and a determination is made by the 

agency issuing the weed abatement order that, due to fire 

hazard conditions, rocks, or other physical obstructions, it 

is not practical to meet the conditions specified in clause 

(g)(1)(H)(i). The provisions this clause shall not exempt 

the owner of any property from stabilizing, in accordance 

with paragraph (d)(2), disturbed surface areas which have 

been created as a result of the weed abatement actions. 

(K) sandblasting operations. 

(2) The provisions of paragraphs (d)(1) and (d)(3) shall not apply: 

(A) When wind gusts exceed 25 miles per hour, provided that: 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 11 

(i) The required Table 3 contingency measures in this Rule are 

implemented for each applicable fugitive dust source type, 

and; 

(ii) records are maintained in accordance with subparagraph 

(e)(1)(C). 

(B) To unpaved roads, provided such roads: 

(i) are used solely for the maintenance of wind-generating 

equipment; or 

(ii) are unpaved public alleys as defined in Rule 1186; or 

(iii) are service roads that meet all of the following criteria: 

(a) are less than 50 feet in width at all points along the 

road; 

(b) are within 25 feet of the property line; and 

(c) have a traffic volume less than 20 vehicle-trips per 

day. 

(C) To any active operation, open storage pile, or disturbed surface 

area for which necessary fugitive dust preventive or mitigative 

actions are in conflict with the federal Endangered Species Act, as 

determined in writing by the State or federal agency responsible 

for making such determinations. 

(3) The provisions of (d)(2) shall not apply to any aggregate-related plant or 

cement manufacturing facility that implements the applicable actions 

specified in Table 2 of this Rule at all times and shall implement the 

applicable actions specified in Table 3 of this Rule when the applicable 

performance standards of paragraphs (d)(1) and (d)(3) can not be met 

through use of Table 2 actions. 

(4) The provisions of paragraphs (d)(1), (d)(2), and (d)(3) shall not apply to: 

(A) Blasting operations which have been permitted by the California 

Division of Industrial Safety; and 

(B) Motion picture, television, and video production activities when 

dust emissions are required for visual effects. In order to obtain 

this exemption, the Executive Officer must receive notification in 

writing at least 72 hours in advance of any such activity and no 

nuisance results from such activity. 

(5) The provisions of paragraph (d)(3) shall not apply if the dust control 

actions, as specified in Table 2, are implemented on a routine basis for 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 12 

each applicable fugitive dust source type. To qualify for this exemption, a 

person must maintain records in accordance with subparagraph (e)(1)(C). 

(6) The provisions of paragraph (d)(4) shall not apply to earth coverings of 

public paved roadways where such coverings are approved by a local 

government agency for the protection of the roadway, and where such 

coverings are used as roadway crossings for haul vehicles provided that 

such roadway is closed to through traffic and visible roadway dust is 

removed within one day following the cessation of activities. 

(7) The provisions of subdivision (e) shall not apply to: 

(A) officially-designated public parks and recreational areas, including 

national parks, national monuments, national forests, state parks, 

state recreational areas, and county regional parks. 

(B) any large operation which is required to submit a dust control plan 

to any city or county government which has adopted a Districtapproved dust control ordinance. 

(C) any large operation subject to Rule 1158, which has an approved 

dust control plan pursuant to Rule 1158, provided that all sources 

of fugitive dust are included in the Rule 1158 plan. 

(8) The provisions of subparagraph (e)(1)(A) through (e)(1)(C) shall not apply 

to any large operation with an AQMD-approved fugitive dust control plan 

provided that there is no change to the sources and controls as identified in 

the AQMD-approved fugitive dust control plan. 

(h) Fees 

 Any person conducting active operations for which the Executive Officer 

conducts upwind/downwind monitoring for PM10 pursuant to paragraph 

(d)(3) shall be assessed applicable Ambient Air Analysis Fees pursuant to 

Rule 304.1. Applicable fees shall be waived for any facility which is 

exempted from paragraph (d)(3) or meets the requirements of paragraph 

(d)(3). 
Rule 403 (cont.) (Amend

TABLE 1 

BEST AVAILABLE CONTROL MEASURES 

(Applicable to All Construction Activity Sources) 

403 - 13 

Source Category Control Measure Backfilling 01-1 

01-2 01-3 

Stabilize backfill material when not actively handling; and Stabilize backfill material during handling; and Stabilize soil at completion of activity. 

9 Mix backfill soil with water 9 Dedicate water truck or high 

backfilling equipment 

9 Empty loader bucket slowly 

plumes are generated 

9 Minimize drop height from 

Clearing and grubbing 

02-1 02-2 02-3 

Maintain stability of soil through pre-watering of site prior to clearing and grubbing; and Stabilize soil during clearing and grubbing 

activities; and Stabilize soil immediately after clearing and 

grubbing activities. 

9 Maintain live perennial vege

possible 

9 Apply water in sufficient qua

generation of dust plumes 

Clearing forms 03-1 

03-2 03-3 

Use water spray to clear forms; or Use sweeping and water spray to clear forms; or Use vacuum system to clear forms. 

9 Use of high pressure air to cl

exceedance of Rule requirem

Crushing 04-1 

04-2 

Stabilize surface soils prior to operation of support equipment; and Stabilize material after crushing. 

9 Follow permit conditions for 

9 Pre-water material prior to lo9 Monitor crusher emissions o9 Apply water to crushed mate

plumes 
Rule 403 (cont.) (Ame

TABLE 1 

BEST AVAILABLE CONTROL MEASURES 

(Applicable to All Construction Activity Sources) 

403 - 14 

Source Category Control Measure Guidance Cut and fill 05-1 

05-2 

Pre-water soils prior to cut and fill activities; and Stabilize soil during and after cut and fill activities. 

9 For large sites, pre-wat

water trucks and allow 

9 Use water trucks/pulls 

of cut prior to subsequ

Demolition – mechanical/manual 

06-1 

06-2 06-3 06-4 

Stabilize wind erodible surfaces to reduce dust; and Stabilize surface soil where support equipment and vehicles will operate; and Stabilize loose soil and demolition debris; and Comply with AQMD Rule 1403. 

9 Apply water in sufficie

prevent the generation 

Disturbed soil 07-1 

07-2 

Stabilize disturbed soil throughout the construction site; and Stabilize disturbed soil between structures 

9 Limit vehicular traffic 

soils where possible 

9 If interior block walls 

early as possible 

9 Apply water or a stab

sufficient quantities to generation of visible d

Earth-moving activities 

08-1 08-2 08-3 

Pre-apply water to depth of proposed cuts; and Re-apply water as necessary to maintain soils in a damp condition and to ensure that visible emissions do not exceed 100 feet in any direction; and Stabilize soils once earth-moving activities are complete. 

9 Grade each project ph

to coincide with const

9 Upwind fencing can p

movement on site 

9 Apply water or a stab

sufficient quantities to generation of visible d
Rule 403 (cont.) (Ame

TABLE 1 

BEST AVAILABLE CONTROL MEASURES 

(Applicable to All Construction Activity Sources) 

403 - 15 

Source Category Control Measure Guidance Importing/exporting of bulk materials 

09-1 

09-2 09-3 09-4 09-5 

Stabilize material while loading to reduce fugitive dust emissions; and Maintain at least six inches of freeboard on haul vehicles; and Stabilize material while transporting to reduce fugitive dust emissions; and Stabilize material while unloading to reduce fugitive dust emissions; and Comply with Vehicle Code Section 23114. 

9 Use tarps or other suita

haul trucks 

9 Check belly-dump truc

remove any trapped ro

9 Comply with track-out 

prevention/mitigation r

9 Provide water while lo

to reduce visible dust p

Landscaping 10-1 Stabilize soils, materials, slopes 9 Apply water to materia

9 Maintain materials in a 

9 Maintain effective cov

9 Stabilize sloping surfa

until vegetation or groueffectively stabilize the 

9 Hydroseed prior to rain 

Road shoulder maintenance 

11-1 11-2 

Apply water to unpaved shoulders prior to clearing; and Apply chemical dust suppressants and/or washed gravel to maintain a stabilized surface after completing road shoulder maintenance. 

9 Installation of curbing 

shoulders can reduce recosts 

9 Use of chemical dust s

inhibit vegetation growroad shoulder maintena
Rule 403 (cont.) (Ame

TABLE 1 

BEST AVAILABLE CONTROL MEASURES 

(Applicable to All Construction Activity Sources) 

403 - 16 

Source Category Control Measure Guidance Screening 12-1 

12-2 12-3 

Pre-water material prior to screening; and Limit fugitive dust emissions to opacity and plume length standards; and Stabilize material immediately after screening. 

9 Dedicate water truck o

to screening operation 

9 Drop material through 

minimize drop height 

9 Install wind barrier wit

more than 50% upwind height of the drop poin

Staging areas 13-1 

13-2 

Stabilize staging areas during use; and Stabilize staging area soils at project completion. 

9 Limit size of staging ar

9 Limit vehicle speeds to 9 Limit number and size 

entrances/exists 

Stockpiles/ Bulk Material Handling 

14-1 

14-2 

Stabilize stockpiled materials. Stockpiles within 100 yards of off-site occupied buildings must not be greater than eight feet in height; or must have a road bladed to the top to allow 

water truck access or must have an operational water irrigation system that is capable of complete stockpile coverage. 

9 Add or remove materia

portion of the storage p

9 Maintain storage piles 

or faces 
Rule 403 (cont.) (Ame

TABLE 1 

BEST AVAILABLE CONTROL MEASURES 

(Applicable to All Construction Activity Sources) 

403 - 17 

Source Category Control Measure Guidance Traffic areas for construction activities 

15-1 

15-2 15-3 

Stabilize all off-road traffic and parking areas; and Stabilize all haul routes; and Direct construction traffic over established haul routes. 

9 Apply gravel/paving to 

soon as possible to all 

9 Barriers can be used to 

only used on establisheroutes 

Trenching 16-1 

16-2 

Stabilize surface soils where trencher or excavator and support equipment will operate; and Stabilize soils at the completion of trenching activities. 

9 Pre-watering of soils p

effective preventive mtrenching activities, presoak soils via the pre-ttrenching 

9 Washing mud and soil

the conclusion of trencprevent crusting and drequipment 

Truck loading 17-1 

17-2 

Pre-water material prior to loading; and Ensure that freeboard exceeds six inches (CVC 23114) 

9 Empty loader bucket su

dust plumes are created 

9 Ensure that the loader 

truck to minimize drop 

Turf Overseeding 18-1 

18-2 

Apply sufficient water immediately prior to conducting turf vacuuming activities to meet opacity and plume length standards; and Cover haul vehicles prior to exiting the site. 

9 Haul waste material im
Rule 403 (cont.) (Ame

TABLE 1 

BEST AVAILABLE CONTROL MEASURES 

(Applicable to All Construction Activity Sources) 

403 - 18 

Source Category Control Measure Guidance Unpaved roads/parking lots 

19-1 19-2 

Stabilize soils to meet the applicable performance standards; and Limit vehicular travel to established unpaved roads 

(haul routes) and unpaved parking lots. 

9 Restricting vehicular a

unpaved travel paths anreduce stabilization req

Vacant land 20-1 In instances where vacant lots are 0.10 acre or larger 

and have a cumulative area of 500 square feet or more that are driven over and/or used by motor vehicles and/or off-road vehicles, prevent motor vehicle and/or off-road vehicle trespassing, parking and/or access by installing barriers, curbs, fences, gates, posts, signs, shrubs, trees or other effective control measures. 
Rule 403 (cont.) (Amended June 3, 2005) 

403 - 19 

Table 2 

DUST CONTROL MEASURES FOR LARGE OPERATIONS 

FUGITIVE DUST 

SOURCE CATEGORY 

 

CONTROL ACTIONS 

Earth-moving (except 

construction cutting and 

filling areas, and mining 

operations) 

(1a) Maintain soil moisture content at a minimum of 

12 percent, as determined by ASTM method D2216, or other equivalent method approved by 

the Executive Officer, the California Air 

Resources Board, and the U.S. EPA. Two soil 

moisture evaluations must be conducted during 

the first three hours of active operations during a 

calendar day, and two such evaluations each 

subsequent four-hour period of active operations; 

OR

(1a-1) For any earth-moving which is more than 100 

feet from all property lines, conduct watering as 

necessary to prevent visible dust emissions from 

exceeding 100 feet in length in any direction. 

Earth-moving: 

Construction fill areas: 

(1b) Maintain soil moisture content at a minimum of 

12 percent, as determined by ASTM method D2216, or other equivalent method approved by 

the Executive Officer, the California Air 

Resources Board, and the U.S. EPA. For areas 

which have an optimum moisture content for 

compaction of less than 12 percent, as 

determined by ASTM Method 1557 or other 

equivalent method approved by the Executive 

Officer and the California Air Resources Board 

and the U.S. EPA, complete the compaction 

process as expeditiously as possible after 

achieving at least 70 percent of the optimum soil 

moisture content. Two soil moisture evaluations 

must be conducted during the first three hours of 

active operations during a calendar day, and two 

such evaluations during each subsequent fourhour period of active operations. 
Rule 403 (cont.) (Amended June 3, 2005) 

403-20 

Table 2 (Continued) 

FUGITIVE DUST 

SOURCE CATEGORY 

 

CONTROL ACTIONS 

Earth-moving: 

Construction cut areas 

and mining operations: 

(1c) Conduct watering as necessary to prevent visible 

emissions from extending more than 100 feet 

beyond the active cut or mining area unless the area 

is inaccessible to watering vehicles due to slope 

conditions or other safety factors. 

Disturbed surface areas 

(except completed 

grading areas) 

(2a/b) Apply dust suppression in sufficient quantity and 

frequency to maintain a stabilized surface. Any 

areas which cannot be stabilized, as evidenced by 

wind driven fugitive dust must have an application 

of water at least twice per day to at least 80 percent 

of the unstabilized area. 

Disturbed surface 

areas: Completed 

grading areas 

(2c) Apply chemical stabilizers within five working days 

of grading completion; OR 

 (2d) Take actions (3a) or (3c) specified for inactive 

disturbed surface areas. 

Inactive disturbed 

surface areas 

(3a) Apply water to at least 80 percent of all inactive 

disturbed surface areas on a daily basis when there is 

evidence of wind driven fugitive dust, excluding any 

areas which are inaccessible to watering vehicles due 

to excessive slope or other safety conditions; OR

 (3b) Apply dust suppressants in sufficient quantity and 

frequency to maintain a stabilized surface; OR 

 (3c) Establish a vegetative ground cover within 21 days 

after active operations have ceased. Ground cover 

must be of sufficient density to expose less than 30 

percent of unstabilized ground within 90 days of 

planting, and at all times thereafter; OR 

 (3d) Utilize any combination of control actions (3a), (3b), 

and (3c) such that, in total, these actions apply to all 

inactive disturbed surface areas. 
Rule 403 (cont.) (Amended June 3, 2005) 

403-21 

Table 2 (Continued) 

FUGITIVE DUST 

SOURCE CATEGORY 

 

CONTROL ACTIONS 

Unpaved Roads (4a) Water all roads used for any vehicular traffic at 

least once per every two hours of active 

operations [3 times per normal 8 hour work day]; 

OR 

 (4b) Water all roads used for any vehicular traffic 

once daily and restrict vehicle speeds to 15 miles 

per hour; OR 

 (4c) Apply a chemical stabilizer to all unpaved road 

surfaces in sufficient quantity and frequency to 

maintain a stabilized surface. 

Open storage piles (5a) Apply chemical stabilizers; OR 

 (5b) Apply water to at least 80 percent of the surface 

area of all open storage piles on a daily basis 

when there is evidence of wind driven fugitive 

dust; OR 

 (5c) Install temporary coverings; OR 

 (5d) Install a three-sided enclosure with walls with no 

more than 50 percent porosity which extend, at a 

minimum, to the top of the pile. This option may 

only be used at aggregate-related plants or at 

cement manufacturing facilities. 

All Categories (6a) Any other control measures approved by the 

Executive Officer and the U.S. EPA as 

equivalent to the methods specified in Table 2 

may be used. 
Rule 403 (cont.) (Amended June 3, 2005) 

403-22 

TABLE 3 

CONTINGENCY CONTROL MEASURES FOR LARGE OPERATIONS 

FUGITIVE DUST 

SOURCE 

CATEGORY 

CONTROL MEASURES 

Earth-moving (1A) Cease all active operations; OR 

(2A) Apply water to soil not more than 15 minutes prior to 

moving such soil. 

Disturbed surface 

areas 

(0B) On the last day of active operations prior to a 

weekend, holiday, or any other period when active 

operations will not occur for not more than four 

consecutive days: apply water with a mixture of 

chemical stabilizer diluted to not less than 1/20 of the 

concentration required to maintain a stabilized 

surface for a period of six months; OR 

(1B) Apply chemical stabilizers prior to wind event; OR 

(2B) Apply water to all unstabilized disturbed areas 3 

times per day. If there is any evidence of wind driven 

fugitive dust, watering frequency is increased to a 

minimum of four times per day; OR 

(3B) Take the actions specified in Table 2, Item (3c); OR 

(4B) Utilize any combination of control actions (1B), (2B), 

and (3B) such that, in total, these actions apply to all 

disturbed surface areas. 

Unpaved roads (1C) Apply chemical stabilizers prior to wind event; OR 

(2C) Apply water twice per hour during active operation; 

OR 

(3C) Stop all vehicular traffic. 

Open storage piles (1D) Apply water twice per hour; OR 

(2D) Install temporary coverings. 

Paved road track-out (1E) Cover all haul vehicles; OR 

(2E) Comply with the vehicle freeboard requirements of 

Section 23114 of the California Vehicle Code for 

both public and private roads. 

All Categories (1F) Any other control measures approved by the 

Executive Officer and the U.S. EPA as equivalent to 

the methods specified in Table 3 may be used. 
Rule 403 (cont.) (Amended June 3, 2005) 

403-23 

Table 4 

(Conservation Management Practices for Confined Animal Facilities) 

SOURCE 

CATEGORY 

CONSERVATION MANAGEMENT PRACTICES 

Manure 

Handling 

(1a) 

(1b)

Cover manure prior to removing material off-site; AND 

Spread the manure before 11:00 AM and when wind conditions 

are less than 25 miles per hour; AND

(Only 

applicable to 

Commercial 

Poultry 

Ranches) 

(1c) 

(1d) 

Utilize coning and drying manure management by removing 

manure at laying hen houses at least twice per year and maintain 

a base of no less than 6 inches of dry manure after clean out; or 

in lieu of complying with conservation management practice 

(1c), comply with conservation management practice (1d). 

Utilize frequent manure removal by removing the manure from 

laying hen houses at least every seven days and immediately 

thin bed dry the material. 

Feedstock 

Handling 

(2a) Utilize a sock or boot on the feed truck auger when filling feed 

storage bins. 

Disturbed 

Surfaces 

(3a) 

(3b) 

(3c) 

Maintain at least 70 percent vegetative cover on vacant portions 

of the facility; OR 

Utilize conservation tillage practices to manage the amount, 

orientation and distribution of crop and other plant residues on 

the soil surface year-round, while growing crops (if applicable) 

in narrow slots or tilled strips; OR 

Apply dust suppressants in sufficient concentrations and 

frequencies to maintain a stabilized surface. 

Unpaved 

Roads 

(4a) 

(4b) 

(4c) 

Restrict access to private unpaved roads either through signage 

or physical access restrictions and control vehicular speeds to 

no more than 15 miles per hour through worker notifications, 

signage, or any other necessary means; OR 

Cover frequently traveled unpaved roads with low silt content 

material (i.e., asphalt, concrete, recycled road base, or gravel to 

a minimum depth of four inches); OR 

Treat unpaved roads with water, mulch, chemical dust 

suppressants or other cover to maintain a stabilized surface. 

Equipment 

Parking Areas 

(5a) 

(5b) 

Apply dust suppressants in sufficient quantity and frequency to 

maintain a stabilized surface; OR 

Apply material with low silt content (i.e., asphalt, concrete, 

recycled road base, or gravel to a depth of four inches).