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# Air Sciences

DRAFT FINAL

TECHNICAL MEMORANDUM

REGULATION VIII BACM ANALYSIS

Prepared for

Imperial County Air Pollution Control District

150 South 9 th 

# Street

El Centro, CA. 92243-2801

Prepared by

ENVIRON International Corporation

707 Wilshire Blvd., Suite 4950

Los Angeles, CA 90017

October 2005

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L -i- E N V I R O N 

# TABLE OF CONTENTS

Page

1. INTRODUCTION ................................................................................................................ ...1

Background ..................................................................................................................... .........1

Best Available Control Measure (B ACM) Development and Assessment .............................2

Purpose........................................................................................................................ .............3

Report Organization............................................................................................................ .....4

2. DETERMINATION OF PM 10 

# DE MINIMUS LEVELS........................................................5

Background ..................................................................................................................... .........5

Ambient PM 10 

# and Related Emission Inventories ...................................................................5

Calculation of DM Levels....................................................................................................... .7

Analysis of Major PM 10 

# Stationary Sources............................................................................8

3. SIGNIFICANT AND DE MINI MIS SOURCE CATEGORIES.............................................9

Emission Inventory ............................................................................................................. .....9

Inventory Discussion ........................................................................................................... ..10

Conclusions.................................................................................................................... ........15

4. COMPARATIVE ANALYSIS..............................................................................................17

Introduction................................................................................................................... .........17

Comparative Analysis fo r Significant Sources ......................................................................18

Sources on BLM Lands .........................................................................................................18

Comparative Analysis for Sources With Emissions Less Than the DM Level .....................38

5. IMPACT ANALYSIS............................................................................................................3 9

Control Effectiveness and Cost Information..........................................................................39

PR 801: Construction................................................................................................. 40

PR 802: Bulk Materials.............................................................................................. 40

PR 803: Carry-out and Track-out .............................................................................. 41

PR 804: Open Areas................................................................................................... 41

PR 805: Paved and Unpaved Roads........................................................................... 42

PR 806: Conservation Ma nagement Practices........................................................... 42

Cost-Effectiveness ............................................................................................................. ....43

6. CONCLUSIONS................................................................................................................. ...58

# Technical Memorandum: Regulation VIII BACM Analysis October 2005



# TABLE OF CONTENTS

(Continued)

Page

D R A F T F I N A L -ii- E N V I R O N 

# APPENDICES

Appendix A: Technical Memorandum: Latest Revisions of the Windblown Dust Study

Appendix B: Entrained and Windblown Emissions From Unpaved Roads

Appendix C: Detailed Comparative Analysis for Significant Sources

Appendix D: Detailed Comparative Analysis for Sources Below the De Minimis Level

Appendix E: Draft Regulation VIII Rules a nd Rule Amendments (dated October 2005)

Appendix F: BLM Environmental Assessment and Finding of No Significant Impact

TABLES

Table 2-1. Annual Average PM 10 

# levels in μg/m3........................................................................6

Table 2-2. 24-Hour Average PM 10 

# levels in μg/m3 ......................................................................6

Table 2-3. Annual Average PM 10 

# Emission Inventories for Imperial County in tons/day

(Only non-zero categories are reported) ......................................................................7

Table 2-4. Summer Average PM 10 

# Emission Inventories for Imperial County in tons/day

(Only non-zero categories are reported) ......................................................................7

Table 3-1. 2004 Annual Average PM 10 

# Emission Inventories for Imperial County in

tons/day....................................................................................................................... .9

Table 3-2. Windblown Emissions from Lands by Month and Annual Average (tons/day)........12

Table 3-3. Windblown Emissions from Unpaved Roads............................................................13

Table 3-4. Entrained Unpaved Road Emissions..........................................................................14

Table 3-5. Imperial County Cattle-Related PM 10 

# Emissions ......................................................15

Table 3-6. Significant Source Categories of PM 10 

# (2004 emissions in tons/day).......................16

Table 3-7. De Minimis Source Categories That Emit Greater than 1 ton/day of PM 10 

# (These are NOT signifi cant source categories)..........................................................16

Table 3-8. De Minimus Source Categorie s That Emit Less than 1 ton/day of PM 10 

# ..................16

Table 4-1. Dust Control Source Categor ies for Sources above the DM Level ...........................18

Table 4-2. Dust Control Source Categor ies For Sources Above the DM Level .........................21

Table 4-3. Dust Control Source Categor ies For Sources Below the DM Limit..........................38

Table 5-1. Proposed Regulation VI II Emission Reduction Summary ........................................39

# Technical Memorandum: Regulation VIII BACM Analysis October 2005



# TABLE OF CONTENTS

(Continued)

Page

D R A F T F I N A L -iii- E N V I R O N 

# Table 5-2. Cost-effectiveness of measures in Proposed Rule 801 – Construction and

Demolition .................................................................................................................45

Table 5-3. Cost-effectiveness of measures in Proposed Rule 802 – Bulk Materials ..................46

Table 5-4. Cost-effectiveness of measures in Proposed Rule 803 – Track-out and Carry-out ...47

Table 5-5. Cost-effectiveness of measur es in Proposed Rule 804 – Open Areas .......................48

Table 5-6. Cost-effectiveness of measures in Proposed Rule 805 – Paved and Unpaved

Roads.......................................................................................................................... 49

Table 5-7. Cost-effectiveness of measur es in Proposed Rule 806 – Conservation

Management Practices ...............................................................................................51

Table 5-8 Senate Bill 656 Measures Not in the Proposed Regulation VIII Amended Rules.....52

FIGURES

Figure 1-1: Imperial County .................................................................................................... .....1

Figure 3-1: Land Use and Land Classificat ion Categories in Imperial County .........................11

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L -iv- E N V I R O N 

# ABBREVIATIONS AND ACRONYMS

ADVT Average daily vehicle trips

BLM U.S. Department of Interior Bureau of Land Management

BMP Best Management Practice (agriculture)

BP Border Patrol

CAA Federal Clean Air Act

CARB California Air Resources Board

CMP Conservation ManagementPractice (agriculture)

IC Imperial County

ICAPCD Imperial County Air Pollution Control District

IID Imperial Irrigation District

NAAQS National Ambient Air Quality Standards

NEPA National Environmental Policy Act

PM particulate matter

PM 10 

# particulate mater less than 10 μm in aerodynamic diameter

SCAQMD South Coast Air Quality Management District

SIP State Implementation Plan

SJV San Joaquin Valley

SJVAPCD San Joaquin Valley Unified Ai r Pollution Control District

TSP total suspended partic ulates (less than 30 ∝ m in aerodynamic diameter)

USEPA United States Environmental Protection Agency

VDT Vehicle daily trips

μg/m 3 

# microgram per cubic meter

μm micron or micrometer

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -1- 

# 1. INTRODUCTION

Background

Imperial County is located in the southeastern portion of California and borders Mexicali, Mexico.

The climate is hot and dry, ranging from lows in the mid 30's in January to highs of 110°F+ in July

and August (mean annual temperatures: low-55.0°F; of high-89.6°F), with little moisture (average

annual rainfall: 2.92 inches; 25 percent average re lative humidity). Imperi al County extends over

4,597 square miles, bordering Mexico to the so uth, Riverside County to the north, San Diego

County to the west, and the State of Arizona to the east. The terrai n varies from 235 feet below sea

level at the Salton Sea to 4,548 feet above sea level at Blue Angel Peak. The population of all of

Imperial County is about 149,300 people. The princi pal industries are farm ing and retail trade.

Most of the population, farming, and retail trade exists in a band of land on average less than 1/4th

the width of the county that stretc hes from the south shore of the Salton Sea to the Mexican border,

where road network is densest, as shown in Figure 1.

Figure 1-1: Imperial County

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -2- 

# Much of the rest of Imperial County is desert or barren areas that are sparsely populated or

unpopulated. In Imperial County, elevated PM 10 

# levels can result from disturbance of soils by wind

and human activity, and from transport from Mexico. Likely PM 10 

# sources include the large desert

areas (during high winds), unpaved roads, waste burning, agriculture , vacant lots, Immigration and

Naturalization Service (Border Patrol) activities al ong the border, and Mexican sources.

Best Available Control Measure (BACM) Development and Assessment

USEPA issued a finding on August 3, 2004 that Imperial Valley failed to attain the PM 10 

# NAAQS

by the statutory deadline of December 31, 1994, and th erefore reclassified the area from a moderate

to a serious PM 10 

# nonattainment area. Also on August 3, 2004, USEPA proposed to find that the

Imperial Valley failed to attain by the serious area attainment date of December 31, 2001. The

proposed rule generally described the necessary plan requirements and would require Imperial

County submit its clean air plan, including BACM, with in one year of the fi nal action. As of the

date of this report, USEPA has not taken fi nal action. In addition, ICAPCD on August 9, 2005

approved a natural event action pl an (NEAP) to support the exclus ion of natural events from

attainment determinations, as allowed by USEPA’ s Natural Event Policy (N EP). Although the final

action by USEPA has not occurred, ICAPCD has proposed Regulation VIII BACM rules. EPA

guidance recommends the following procedure for demonstrating the BACM has been implemented

on all significant sources:

 Inventory sources of PM 10 

# and PM 10 

# precursors

 Determine a de minimis level for each pollutant

 Identify significant source categories

 Identify candidate cont rol measures/technologies

 Evaluate alternative control technologies for:

- Technical feasibility analysis

- Economic feasibility analysis

- Environmental impacts

- 

# Select and implement measures

Traditionally, BACM development and assessmen t would be based on the State Implementation

Plan (SIP) and its technical analyses. Key t echnical issues concerni ng emission inventory and

natural events have not been resolved at this time. Unlike other serious non-attainment areas,

ICAPCD is preparing its fugitive dust BACM in advance of the development and approval of a SIP.

ICAPCD has prepared proposed Regulation VIII BA CM (based on other recent serious area BACM

rules) to meet the requirements of the NEP a nd to expedite BACM emission reductions. In

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -3- 

# March 2004, ICAPCD began a review and assessment of BACM in other areas, which it has used as

the basis on its proposed Regulation VIII BACM amendments. In October 2004 it gave a BACM

presentation to local stakeholders that initiate d the BACM rule development. ICAPCD prepared

and released proposed Regulation VIII BACM ru les in December 2004. These rules are being

developed through a public process that includes a local Technical Advisory Committee (TAC).

Membership in the TAC group includes represen tatives from Coalition of Labor and Business

(COLAB), Farm Bureau, farmers, private indust ry, Bureau of Land Management (BLM), Border

Patrol, Imperial Irrigation Dist rict, County Public Works Depa rtment and APCD. The initial

meeting was December 16, 2004, with subsequent meetings held on January 4, 2005, January 11 th



# , January 24 th 

# , and March 22 nd 

# . For the first time, on March 23 , 2005, the TAC held a meeting with

EPA to review EPA’s comments and receive in formation that would be useful in amending

Regulation VIII rules. ARB participated by tele conference. The ICAPCD also conducted six

public workshops to collect comments on Regula tion VIII rules in Brawley, El Centro and

Holtville. Workshop were held on May 31 st 

# , June 1 st 

# (two workshops) and June 2 nd 

# (two

workshops), and August 4 th 

# . ICAPCD then re-submitted the Draft Regulation VIII Rules to EPA

and ARB, for a second time, for informal co mments. The EPA and ARB commented on these

rules. On August 10, 2005, the district held a me eting with ARB and EPA at ARB’s headquarters,

in Sacramento, to discuss their comments. An ag reement was reached with EPA if their comments

were addressed, that Regulation VIII rules would be declared BACM. Informal comments on these

rules were also submitted by US Marine Corps and the California Department of Transportation

(Caltrans). The current schedule is for the ICAPCD Board to hold an adoption hearing in November

2005.

Purpose

This report presents the BACM determination base d on proposed Regulation VIII amendments. It

includes all elements of a BACM determination, including inventor y assessment, calculation of the

de minimis emission level, identification of signi ficant sources (e.g. those sources which emit more

than the de minimis level of emissions), a co mparative analysis of proposed Regulation VIII

amendments for significant sources w ith regulations adopted by serious PM 10 

# non-attainment areas,

and a presentation of the cost-e ffectiveness of indivi dual dust control measures. The proposed

Regulation VIII BACM amendments are based on BACM recently adopted by other serious nonattainment areas. As shown in this report, they apply to all significant fugitive dust sources in

Imperial County and certain non-significant sour ces. This technical memorandum is based on

USEPA’s guidance on BACM development and assessmen t, including: 1) an inventory sources of

PM 10 

# and PM 10 

# precursors, 2) determination a de minimi s level for each pollutant, 3) identification

of significant source categories, 4) a comparative analysis of propos ed Regulation VIII amendments

and BACM in other serious non-atta inment areas, and 5) emission re ductions and costs associated

with proposed Regulation VIII rules, as well as th e cost-effectiveness of Regulation VIII measures

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -4- 

# based on previous BACM analyses. These elements of a BACM assessment traditionally done in a

SIP are being developed outside of the traditional SIP process to meet the requirements and

schedule of the NEP and accelerate BACM implementation.

Report Organization

This report is organized as follows:

 Section 2 presents a determination of PM 10 

# De Minimis Levels for Imperial County based

on the current emission inventor y and ambient measurements.

 Section 3 assesses the current PM 10 

# emission inventory and id entifies the potentially

significant sources of PM 10 

# . This also includes an analys is of major stationary sources.

 Section 4 presents the comparative analysis of the proposed Regulation VIII amendments

with BACM in other serious PM 10 

# non-attainment areas.

 Section 5 presents the cost-effectiveness of proposed Regulation VIII amendments based on

the cost-effectiveness analyses of previous BACM determinations.

 Section 6 presents the conclusions an d recommendations of this report.

 Appendix A is an ENVIRON Technical Memorandu m that presents the latest revisions of

the Windblown Dust Study, which is used to ca lculate windblown from all sources except

unpaved roads.

 Appendix B presents the updated entrai ned and windblown unpaved road emission

estimates.

 Appendix C presents a detailed comparative analysis on a source-by -source basis for all

proposed Regulation VIII rules for those sour ces with emissions above the de minimis

emissions level.

 Appendix D presents a detailed comparative analysis on a source-by -source basis for all

proposed Regulation VIII rules for those sour ces with emissions below the de minimis

emissions level. A comparative analysis is not required for these s ources and is presented

for informational purposes only.

 Appendix E contains the version of the propos ed Regulation VIII rule s dated October 2005.

This analysis is based upon this version of the proposed rules.

 Appendix F is the Environmental Assessmen t and Finding of No Significant Impact

prepared by BLM in April 2002 for Road and Tr ail Maintenance related to Border Patrol

activities in Imperial County.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -5- 

# 2. DETERMINATION OF PM 10 

# DE MINIMUS LEVELS

Background

USEPA has established de minimis (DM) crit eria for source categor ies contributing to PM 10



# . Specifically, USEPA has established a sour ce category contribution level of 1 μg/m 3 

# based on the

annual average PM 10 

# national ambient air quality standard (NAAQS) and 5 μg/m 3 

# based on the 24-

hour PM 10 

# NAAQS 1 

# . If a source category contributes more than these levels to measured ambient

PM 10 

# concentrations in a serious nonattainment area, then BACM and/or Best Available Control

Technology (BACT) are required to be implemented for that source. (BAC M applies to certain

area sources and BACT applies to stationary, mostly point, sources). The purpose of this report is

to determine the DM conditions, on an emission per μg/m 3 

# basis, for sources of primary PM 10 

# in

Imperial County. (Ambient PM 10 

# in most of Imperial County (e .g., those areas which do not border

Mexicali) is overwhelmingly primary PM 10 

# , with little or no contribution from secondary aerosols).

Once the DM levels are determined, then any sour ce category which exceeds those limits would be

subject to BACM/BACT. For individual stationary sources that meet the state and/or federal

definition of PM 10 

# major source, the last section of this chapter identifies thos e sources, whether

BACT has been imposed (based on the date of th e latest major modification permit), and, if BACT

has not been applied, an assessment of the impact of the source’s emissions on ambient

concentrations, relative to the significance th resholds. The BACM/BACT requirement does not

apply to mobile sources of emissions.

Ambient PM 10 

# and Related Emission Inventories

The DM level is calculated using the ambient PM 10 

# data and the related emission inventory. There

are six PM 10 

# stations in Imperial County; from nort h to south, Niland, Westmorland, Brawley, El

Centro, Calexico-Grant, and Calexico-Ethel. The last two stations are located in Calexico, next to

the greater Mexicali, Mexico area. As shown in previous 179B(d) submittals, measures in excess

of the annual average PM 10 

# standard at the Calexico stations would not have occurred but for

Mexican PM 10 

# sources 2 

# . Since BACM and BACT can only be applied to U.S. sources, the

Calexico stations will be excluded from the DM le vel determination. It is expected and assumed

that ambient PM 10 

# at these non-border ambient air monitori ng stations is overwhelmingly primary

PM 10 

# . (This is a conservative assumption when cal culating the DM level, e.g., it produces the

1 

# State Implementation Plans for Serious PM 10 

# Non-Attainment Areas, and A ttainment Date Waivers for PM 10 

# NonAttainment Areas Generally; Addendum to the General Prea mble for the Implementation of Title I of the Clean Air

Act Amendments of 1990, Federal Register, Vol. 59, No. 157, August 16, 1994.

2 

# “Imperial County PM 10 

# Attainment Demonstration,” prepared by EN VIRON for the Imperial County Air Pollution

District, July 2001.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -6- 

# smallest DM level.) The annual average PM 10 

# levels for 2002 through 2004 for the non-Calexico

stations are presented in Table 2-1, including the location of the maximum.

Table 2-1. Annual Average PM 10 

# levels in μg/m3



# 2002 2003 2004

Annual Average

PM 10 

# 57.1 (Westmorland) 73.5 (Westmorland)

60.3 without the

flagged wildfire event 56.3 (Westmorland)

The peak 24-hour average values are not as straightforward. Ta ble 2-2 reports the peak 24-hour

average PM 10 

# values for 2002 through 2004. The peak 24-hour average PM 10 

# in 2003 was due to a

wildfire event that has been flagged by USEPA as natural event. The more representative 2 nd 

# peak

24-hour average PM 10 

# values have been provided as more re presentative of local emissions. It

should be noted that ICAPCD has request ed that the August 18, 2002 and August 19, 2003 PM 10



# readings be flagged as natural events; however, for the purposes of this analysis, these readings will

be used in the calculation of the DM level. (Using lower 24- hour average readings would increase

the DM level, so this is a conservative approach.)

Table 2-2. 24-Hour Average PM 10 

# levels in μg/m3



# 2002 2003 2004

Peak 24-Hour Average

PM 10 

# 297

(Westmorland 8/18) 840 1



# (Westmorland 10/30)

2 nd 

# high: 162 (8/19) 354

(Brawley 2/18)

2 nd 

# high: 201

(Westmorland 8/13)

1 

# Wildfire event on October 30, 2003



# Except for the miscellaneous emissions category, emission data are from CARB 2004 emission

inventory. The 2004 emissions invent ory is used since this is the latest published inventory and

there is little variation in the inventory over the 2002 through 2004 timeframe. The miscellaneous

category includes fugitive dust sources such as windblown dust emissions, entrained unpaved and

paved road emissions, construction emissions, and emissions from crop and cattle farming

operations. A more detailed description of the emission inventory can be found in Chapter 3.

Table 2-3 summarizes the Imperial County PM 10 

# emissions, based on the CARB’s published

inventory and revisions to the miscellaneous source emissions described in Chapter 3:

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -7- 

# Table 2-3. Annual Average PM 10 

# Emission

Inventories for Imperial County in

tons/day (Only non-zero categories

are reported)



# Category Year 2004

Fuel Combustion 0.41

Industrial 2.77

Miscellaneous 1 

# 279.98

On-Road Mobile 0.38

Other Mobile 0.69

Total 284.23

1 

# Miscellaneous source emissions are based on 2004 CARB estimates or revisions to

the CARB estimates. See Chapter 3 for details.



# Since peak 24-hour emissions are not reported, our analysis relies on CARB’s reported peak

seasonal (e.g. summer) inventories. For miscella neous source emission estimate, annual average

emission estimates are used for all sources ex cept that the 24-hour hour average windblown

emissions during the highest emitting month ar e used for non-unpaved road area sources (e.g.

agricultural fields, shrub land, barr en desert areas and dunes). Thes e emissions will underestimate

the peak day emissions, since they do not reflect the highest wind days.

Table 2-4. Summer Average PM 10 

# Emission

Inventories for Imperial County in

tons/day (Only non-zero categories are

reported)



# Category Year 2004

Fuel Combustion 0.49

Industrial 2.76

Miscellaneous 543.33

On-Road Mobile 0.38

Other Mobile 0.74

Total 547.7

1 

# Miscellaneous source emissions are based on 2004 CARB

estimates or revisions to the CARB estimates. Windblown

emissions from all areas excep t unpaved roads are based on

highest emission month. See Chapter 3 for details.



# Calculation of DM Levels

The DM level is calculated by determining the em issions that are proportional to either 1 μg/m 3



# (annual average) or 5 μg/m 3 

# (24-hour average), based on the ambient data. The annual average DM

level is derived from dividing the 2004 PM 10 

# emissions of 284.23 tons/day by the average (2002

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -8- 

# through 2004) ambient measurements of 57.9 μg/m 3 

# ; the annual average DM is thus 4.9 tons/day

per μg/m 3 

# . (The wildfire event was excluded fr om the 2003 annual average, since it is

unrepresentative of the annual average emissions. On a year-by-year basis, changing only the

annual average PM 10 

# maximum concentrations, the DM le vel calculation would be 5.0 for 2002,

4.7 for 2003, and 5.0 for 2004.)

For the 24-hour average, the summ er average emissions (547.2 tons /day) are divided by the average

ambient 24-hour PM 10 

# levels (271 μg/m 3 

# ) and then multiplied by 5 (the DM is set by emissions

proportional to 5 μg/m 3 

# ). This is very conservative si nce the summer and/or monthly average

inventory will be smaller than the peak 24-hour in ventory. The calculation s exclude the wildfire

events (10/30/03) as unrepresenta tive of local emissions and unrelat ed to the emissions inventory.

The DM level for the peak 24-hour average is thus 10.1 tons/day per 5 μg/m 3 

# . (On a year-by-year

basis, changing only the 24-hour average PM 10 

# maximum concentrations, the DM level calculation

would be 9.2, 16.9, and 7.7 for 2002, 2003, and 2004, respectively.)

Consistent with a conservative determina tion of the DM level, the DM level for PM 10 

# in Imperial

County is 4.9 tons/day. A further discussion of the DM level and emission source categories is

presented in the next chapter.

Analysis of Major PM 10 

# Stationary Sources

The previous analysis dealt with traditional fugitive PM 10 

# sources and the assessment of their

potential significance as it relates to BACM. Th e de minimis value was determined by comparing

proportional ambient PM 10 

# concentrations to average PM 10 

# emissions. This analysis may not

capture localized effects of major PM 10 

# stationary sources. Stationa ry sources are required to

implement Best Available Contro l Technology (BACT) to control PM 10 

# emissions (Rule 207, New

and Modified Stationary Source Review) and they are also required to co mply with 20% opacity

(Rule 403, Opacity of Emissions). In addition, st ationary sources will be required to mitigate

fugitive dust emissions from access roads, construc tion activities, handling and transferring of bulk

materials and track-out and carry out according to the requirements on Regulation VIII. According

to our 2004 stationary source emissi on inventory, ther e is only one PM 10 

# major stationary source

that operates in Imperial County. This source ma nufactures gypsum wallboa rd and related products

and it is located approximately 20 miles west from the nearest PM 10 

# monitoring site. In addition, it

underwent an expansion within the last ten y ears, during which BACT was implemented on its

major sources. Its impact on ICAPCD PM 10 

# monitors is not significant. Regardless, this source is

required to comply with all the above mentione d requirements and regulations; thus it meets the

requirement for BACM and BACT, whether it is a significant source or not.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -9- 

# 3. Significant and De Mi nimis Source Categories

Emission Inventory

As stated in the introduction, ther e is no existing SIP inventory for Imperial County. This analysis

uses the CARB 2004 PM 10 

# emission inventory, published on CARB’s web site, 3 

# revised cattle

emissions, revised windblown dust model resu lts, and updated entrained and windblown unpaved

road dust estimates. Table 3-1 is a summary of the 2004 PM 10 

# inventory for Imperial County.

Except where noted, the emission estimates are based on the published CARB data. The next

section discusses the revisions to the published CARB data and provides a dditional information on

emission sub-categories. This report follows the same procedures as those in the San Joaquin

Valley BACM/T and RACM/T Demonstration 4 

# . The identification of significant and de minimis

source categories can be found in the C onclusions section of this chapter.

Table 3-1. 2004 Annual Average PM 10 

# Emission Inventories for Imperial County in

tons/day

Source Category PM 10 

# Comment

Fuel Combustion 0.41

Waste Disposal 0.00

Cleaning/Surface

Coatings 0.00

Petroleum Prod/Mktg 0.00

Industrial Processes 2.77 Includes Food / Agri culture (0.16), Mineral Processes (2.61)

Solvent Evaporation 0.00

Res Fuel Combustion 0.09

Farming – Tilling 7.11

Farming – Harvest 0.01

Farming – Cattle 2.62 Revised based on latest cattle population, emission factors and

implementation of Rule 420

Construction 1.91

Paved Road Dust 4.09

Unpaved Road Dust 61.00 Entrained. Revised based on lat est road mileage, activity, and

emission factor estimates.

Windblown –Unpaved

Roads and Open Areas 188.30 Unpaved Roads: Revised based on latest road mileage and

emission factor estimates (30.95)

Open Areas: Windblown Dust Study results, including

Grassland (98.75), Dunes (19.85), Other Barren Lands (38.74),

and Urban (0.01)

3 

# www.arb.ca.gov/app/emsinv/emssumcat_query.php?F_DIV=-

4&F_DD=Y&F_YR=2004&F_SEASON=A&SP=2005&F_AREA=CO&F_CO=13

4 

# Appendix G, BACM/T and RACM/T Demonstration for Sources of PM 10 

# and PM 10 

# Precursors in the San Joaquin

Valley Air Basin. SJVAPCD 2003 PM 10 

# SIP. SJVAPCD. April 2003.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -10- 

# Table 3-1. 2004 Annual Average PM 10 

# Emission Inventories for Imperial County in

tons/day

Source Category PM 10 

# Comment

Windblown – NonPasture Ag Lands 10.81 Windblown Dust Study results

Windblown – Pasture 1.79 CARB estimate

Fires 0.00

Waste Burning 2.19

Cooking 0.06

On-Road Mobile 0.38

Other Mobile 0.69

TOTAL 284.23



# Inventory Discussion

The inventory presented in the draft Regula tion VIII BACM Analysis Report was based on 2003

CARB emission inventory estimates. Based on th e latest emissions modeling for many windblown

dust sources and comments from CARB and EPA, the emission inve ntory for certain categories

highlighted in the draft Report have been review ed and revised. The following sections discuss

those categories that have been revised.

Windblown Dust (Except From Unpaved Roads)

In May 2004, ENVIRON prepared a report entitled “Development of a Windblown Fugitive Dust

Model and Inventory for Imperial County,” for IC APCD (Windblown Dust St udy). The results of

that report indicated that windblown PM 10 

# from agricultural lands in Imperial County were 10.8

tons/day, compared with the CARB estimate of 91.60 tons/day. This initial version of the

Windblown Dust Study also estimated windblown annua l average emissions from open barren lands

to the east and west of the populated areas of Imperial County to be 792 tons/day; the model

assumed that such lands were unvegetated and unst able. ICAPCD submitted this report to CARB

and USEPA for their review and approval of the ne w emission inventory estimates. Based on those

comments, ENVIRON has revised th e windblown emissions model such that only the dune areas to

the east are considered unvegetate d and unstable, and that the re mainder of the barren lands are

stable and 9% vegetated (see Fi gure 3-1). Table 3-2 summari zes the results of the revised

windblown dust estimates.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

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# Figure 3-1: Land Use and Land Classifica tion Categories in Imperial CountyTechnical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A L E N V I R O N-12-Table 3-2. Windblown Emissions from Lands by Month and Annual Average (tons/day)Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec AnnualAgriculture8.59 11.32 19.93 28.48 12.95 16.267.37 4.33 9.76 0.38 6.60 4.4210.81Urban0.07 0.00 0.00 0.03 0.01 0.000.00 0.00 0.00 0.00 0.00 0.000.01Desert - Other20.55 38.09 52.04 97.31 57.09 71.8415.77 43.16 29.29 6.36 22.05 13.3738.74Forest0.07 0.06 0.07 0.15 0.06 0.110.02 0.07 0.03 0.00 0.04 0.020.06Shub/Grassland96.15 102.12 120.63 243.24 97.52 189.8640.64 139.97 63.84 7.32 64.00 25.4098.75Desert - Dunes21.77 31.88 36.23 62.37 24.77 4.5916.73 11.98 8.22 0.00 9.32 11.6419.85TOTAL (TPD) 147.20 183.45 228.91 431.57 192.40 282.67 80.53 199.52 111.1414.06 102.00 54.84 168.22

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

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# As noted, the original Windblown Dust Study esti mate of emissions from barren lands was 792

tons/day. With the revised assumptions, windbl own dust from barren lands is 58.6 tons/day, of

which 19.9 tons/day is emitted from the dune area. Emissions from all other categories are the same

as in the May 2004 Windblown Dust Study Report. CARB and USEPA have recently approved the

use of the Windblown Dust Study for estimating windblown dust emissions for all areas except

unpaved roads. (Windblown unpaved road dus t is estimated using the CARB methodology

described further below.)

Windblown Dust from Unpaved Roads

The CARB inventory web site references the August 1997 Windblown Dust – Unpaved Roads

methodology. The 1993 windblown emissions from unpave d roads in that report are 5.90 tons/day.

Based on discussion with CARB staff, it appears that the additional 73.5 tons/day was based on a

previous estimate of windblown em issions from canal roads that assumed fewer canal road miles

than current estimates and a much higher emissi on factor than curren tly recommended by CARB.

ENVIRON has re-calculated the wi ndblown emissions from all unpa ved roads in Imperial County

using the latest mileage information from Imperial County, the cities of Imperial County and the

Imperial Irrigation District (IID) and the latest CARB emission factor. The results of that analysis

are summarized in Table 3-3.

Table 3-3. Windblown Emissions from Unpaved Roads

Road Type Current CARB

2003 Comment

city/county 7.82 5.9 Consistent

canal 16.76 73.50 Updated emission factor

farm 6.01 -- Not in ARB inventory

BLM/USFS 0.37 -- Not in ARB inventory

Total (tons/day) 30.95 79.40



# The greatest difference between the current estimate s and the previous CARB estimate is canal road

windblown emissions. Previous estimates used a much higher emission factor for windblown dust

related to the canals. Details of the calculation of windblown emissions from unpaved roads can be

found in Appendix B.

Entrained Unpaved Road Dust

ICAPCD has collected updated information on the unpaved roads in its cities and in the county and

along the canals. Previous CA RB estimates were based on an emission factor of 2.27 lbs PM 10 

# /

VMT. The latest CARB-appr oved emission factor, used in the San Joaquin Valley PM 10 

# BACM

analysis, is 2.0 lbs PM 10 

# / VMT. ICAPCD received information from the IC Public Works

Department concerning miles of county roads with 50 or greater ADT. For this current estimated,

ADT was set at the CARB default of 10 for a ll roads except high ADT county roads (assumed 70

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -14- 

# ADT) and canal roads (assumed 5 ADT used in 1993 SI P). Table 3-4 summarizes the results of the

entrained unpaved road emission estimates.

Table 3-4. Entrained Unpaved Road Emissions

Current CARB

2003 Notes

City/County 26.64 16.84 Assumes 70 ADT on high ADT county roads

(if 10 ADT for all roads, ems = 13.62),

consistent with the previous CARB estimate)

Canal 31.56 12.78 1993 SIP: 3,128 mi canals; 1,682 mi canal

roads / Current: 3156 mi canal; 6,312 mi roads.

Assumes 5 trips/day (1993 SIP)

Farm 1.41 1.41 Using new CARB method

BLM/USFS 1.39 2.28 Using CARB methodology and 1993 road

mileage

Total (tons/day) 61.00 33.31



# The current estimate is about twice the previous CARB estimate. The difference is due to higher

ADT estimates for certain county roads, and larger actual miles of canal roads. Information from

the public works departments of Imperial County a nd its cities indicate that there are 7.5 miles of

city roads and 1,354 miles of county roads, of whic h 217 miles have 50 or greater ADT. Entrained

emissions from these city and county roads assu med the CARB default of 10 ADT for all roads,

except the high ADT roads, where an ADT of 70 wa s assumed. As noted in the previous section,

the 1993 SIP assumed 1,682 miles of canal roads, wher eas the latest information from IID indicates

that there are 6,312 miles of canal roads. The current estimate assumes 5 ADT for these roads, as

assumed in the 1993 SIP. There is a discrepancy in the entrained emissions for farm roads that is

probably due to an incorrect activit y level in the previous estimate; the current estimate uses the

latest CARB methodology and parameters.

Cattle Feedlot Dust

The previous emission inventory for this category was in error; cattle feedlot dust was reported in

both categories Cattle Feedlot Dust (ID# 620-616-540-000) and Livestock Husbandry –

Agricultural Waste – Feedlot Cattle (ID# 620-61 8-0262-0103). Also, CARB recently revised the

emission factor for dust from cattle operations. After discussions with CARB staff, a revised PM 10



# inventory for cattle in Imperial County has been calculated (Table 3-5).

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

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# Table 3-5. Imperial County Cattle-Related PM 10 

# Emissions

Livestock

Category 2004 Animal

Totals Emission factor

(lbs PM 10 

# /1000

head/day) Uncontrolled

PM 10 

# emissions

(tons/day) Baseline PM 10



# emissions

(tons/day)

Feedlot Cattle 360,486 28.9 5.21 2.60

Heifers 21,452 see milk cows

Milk cows 3,615 6.72 0.01 0.01

Pink Veal 4,514 NA

TOTAL 390,067 5.22 2.62



# The CARB emission factors are applied to feedlo t and milk cows only, based on the current CARB

methodologies. The CARB milk co w factor assumes the presence of young stock, such as heifers

and calves. There is currently no approved CARB emission factor for heifers and calves separate

from milk cows. It is assumed that veal calf emissions are minimal, since they are not in open

corrals. The baseline emissions re flect the effect of ICAPCD Rule 420, which requires that feedlot

manure moisture be maintained between 20 and 40% and other measures. (The analysis assumes

that rule penetration is 100%, si nce Rule 420 applies to all feed yards with more than 10 animals,

and that there is 100% compliance. Emissions are 3.26 tons/day if 80% rule compliance is

assumed.)

Paved Road Dust

The CARB paved road dust estimate is base d on previously assumed VMT levels of 4,569,000

VMT/day. The estimate in the latest vers ion of the EMFAC model is 4,340,000 VMT/day,

approximately 5% less. An update d inventory would result in a smaller emission estimate for paved

road dust. Given the relatively small contribution from paved road dust and the fact that emissions

from this source are below the DM level, the inventory estimate has not formally been updated.

Conclusions

Based on the DM level of 4.9 tons/day, there are four PM 10 

# sources above the de minimis level and

therefore are significant s ource categories in Imperi al County (Table 3-6).

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

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# Table 3-6. Significant Source Categories of PM 10 

# (2004

emissions in tons/day)



# Source Category Emissions

(tons/day PM 10 

# )

Windblown – open non-crop-farm areas 159.14

Unpaved Roads (Entrained and Windblown) 91.95

Windblown – Non-pasture agricultural lands 10.81

Tilling dust 7.11

All other source categories are below the DM le vel. For information purposes only, Table 3-7

presents those sources below the DM leve l that emit more than 1 ton/day of PM 10 

# . It should be

noted that ICAPCD Rule 420 and proposed Regulati on VIII amendments apply to these sources.

However, based on this analysis, BACM is not specifically required for these sources.

Table 3-7. De Minimis Source Categories That Emit Greater

than 1 ton/day of PM 10 

# (These are NOT significant

source categories)



# Source Category 2004 Emissions

(tons/day PM 10 

# )

Paved Road dust 4.09

Industrial (including Mineral) Processes 2.77

Cattle feedlot dust (with Rule 420) 2.62

Waste Burning 2.19

Construction 1.91

Agricultural Burning 1.59

Sources categories that are both below the DM level and contribut e less than 1 ton/day of PM 10 

# are

listed in Table 3-8.

Table 3-8. De Minimus Source Categories That Emit Less

than 1 ton/day of PM 10



# Source Category 2004 Emissions

(tons/day PM 10 

# )

Harvest Operations 0.01

Cooking 0.06

Fuel Combustion (All sources) 0.41

Waste Disposal (All sources) 0.00

Cleaning/Surface Coatings (All sources) 0.00

Petroleum Production / Mrkg (All sources) 0.00

On-Road Mobile* (All sources) 0.38

Other Mobile* (All sources) 0.69

* Not subject to a BACM/BACT analysis.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

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# 4. COMPARATIVE ANALYSIS

Introduction

This chapter presents the comparative analysis for proposed Regulation VIII rules compared to the

fugitive dust rules in other PM 10 

# serious non-attainment areas. The most recent comparative

analysis was done by San Joaquin Valley as part of their 2003 PM 10 

# SIP; this analysis is based

directly on Appendix G of that SIP 5 

# . The serious non-attainment ar eas include San Joaquin Valley,

Maricopa County (Phoenix area), Clark County (Las Vegas area), South Coas t (Los Angeles Basin),

and Coachella Valley (Palm Springs area). As noted in the San Joaquin Valley analysis, the

comparison shows that control programs in the seri ous non-attainment areas are different based on

local conditions and needs. For each of the fugiti ve dust control categories, comparisons are made

between proposed Regulation VIII rules and similar ru les or statutes applicab le to the other serious

non-attainment areas. For significant sources of PM 10 

# (e.g. those with emissions above the DM

level), the comparison will form the basis for ev aluating the stringency of the proposed Regulation

VIII measures compared to similar measures in othe r areas. Any thresholds and/or requirements for

significant sources that are not as stringent as the most stringent in other areas will be justified

based on local conditions, needs, and resources. Regulation VIII applies bot h to sources that are

significant and require a stringen cy evaluation and to sources th at are not significant and do not

require a stringency evaluation.

This section summarizes the comparative analysis for sources above the DM level. For each

significant category, the thresholds and requirements are evaluated for stringency compared to

similar rules in the other serious non-attainment areas. In cases where th e proposed Regulation VIII

rule thresholds and/or requirement s are not as stringent as the mo st stringent thresholds and/or

requirements from other areas, a justification is presented. Appendix C presents a detailed

comparative analysis for sources with emissions greater than the DM leve l, including a stringency

analysis and justification of any measures not deem ed as stringent as the most stringent in other

serious non-attainment areas. Appendix D presen ts a comparative analysis for sources with

emissions below the DM level, although this is not a requirement of a BACM analysis. The

thresholds and requirements for these sources are not evaluated for stringency, as this is not

required. Similarly, the thresholds and requirements for sources in this sec tion do not need to be

justified based on a stringency evaluation. For each of the key source categories, controls

5 

# 2003 San Joaquin Valley PM 10 

# SIP, Appendix G, “Best Available Contro l Measures / Technology and Reasonably

Available Control Measures / Technology Demonstration for Sources of PM 10 

# and PM 10 

# Precursors in the San Joaquin

Valley Air Basin,” April 2004 (Final revised version).

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -18- 

# implemented in the other serious PM 10 

# non-attainment areas are given, along with the citations to

the appropriate rule, statute, or referenced guidan ce. At the end of each segment, a discussion is

provided which highlights the area or areas that have implemented th e most stringent controls. As

noted in the SJVAPCD BACM/T Determination, ther e is no statutory requirement that each control

measure limit and/or requirement be as stringent as the most stringent limit and/or regulation

adopted in any serious non-attainment area.

Comparative Analysis for Significant Sources

The following section presents a summary of the comparative analysis for sources above the DM

level: unpaved roads and areas, disturbed areas, and agricultural sources. Appendix A presents a

detailed comparative analysis of these sources, beginning with general requirements of the proposed

Regulation VIII amendments related to visible dus t emissions and stabilized surfaces for these

sources (e.g., PAR 800, PR 804, PR 805, and PR 806). Next, the comparative analysis for each

specific significant source is presented. Table 4- 1 presents the rule source and control categories

that are considered in the compara tive analysis of the significant PM 10 

# sources. Table 4-2

summarizes the comparative analysis in Appendi x C, including a discussion of the comparative

stringency of the thresholds and requirements for each significant source ca tegory and a justification

if the proposed Regulation VIII thresholds and/or requirements are not as stringent as the most

stringent thresholds and/or requirements fr om other serious non-attainment areas.

Table 4-1. Dust Control Source Categories for Sources above the DM Level



# RULE SOURCE CATEGO RY CONTROL CATEGORY

General Visible Dust Emissions

General Definition of Stabilized Surface

Unpaved Road Dust Applicability

Unpaved Road Dust Control Requirements

Unpaved Lots/Staging Areas Applicability

Unpaved Lots/Staging Areas Requirements

Disturbed Open Areas Applicability

Disturbed Open Areas Control Measures

Disturbed Open Areas Windblown

Agricultural Sources 1 

# Conservation Management Practices (CMPs)

1 

# Only tilling and windblown emissions from agricultural sources are above the DM level, but the full source

category will be compared to BACM in other areas.



# Sources on BLM Lands

In the preceding analysis, unpaved roads and dist urbed open areas are considered significant

sources of PM 10 

# in Imperial County. There are unpaved roads in the lands administered by BLM

and the USFS; entrained and windblown dust from th ese roads is 1.8 tons/day, less than 2% of the

92 tons/day for all unpaved roads. Almost all of the unpaved roads on BLM and USFS lands have

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -19- 

# traffic levels under the Rule 805 threshold of 50 ADT. Of the over 2,666,600 acres comprising

Imperial County over 77% is sc rubland, barren land, or sand dunes. Most of this land is

administered by BLM and the USFS. Except for ar eas used by the military or lands set aside for

OHV use, most of the land is di sturbed only by wind, water, and na tive animals. The lack of

“destination” national or state parks, low Count y population density, general remoteness, and high

summer temperatures minimizes man-made disturbances on most of this land. The exception to this

is special off-roading events held in the dune ar eas. These special events occur 5 to 10 times per

year, for a few days each. The BLM Dust Control Plan in PAR 800 requires control measures for

these special events, even if annual or average da y usage does not meet the thresholds in Rules 804

and 805.

The only Imperial County significant sources on BLM lands are unpaved roads and disturbed open

areas. In addition, PAR 800 only exempts the re creational use of public lands (e.g., OHVs, allterrain vehicles, trucks, cars, motorcycles, moto rbikes or motorbuggies), not other dust-producing

activities such as construction, etc. The BLM Dust Control Pr ovisions make clear that any

stationary source activity must m eet all applicable SIP provisions, including project- or activityspecific BACM. Thus, the focus of the Dust C ontrol Plan provisions are on unpaved road and

disturbed open area sources related to the recreational use of public lands.

BLM sources are considered separate from the gene ral dust source cate gories; this is in recognition

of the special federal purposes of these agenci es (e.g., habitat preservation and compliance with

other area-specific environmental laws) and the inconsistency of requiring certain traditional dust

control methods on these sources (e.g., vegetating disturbed dune areas approved for off-highway

vehicle recreational use.). Many restrictions apply to actions on federal lands that have special

purposes, such as habitats, national monuments and preserves. Common dust control measures,

such as chemical stabilization a nd paving would not be allowed if it endangered native wildlife or

impacted habitats. BLM is required to determin e if a proposed dust contro l project conforms with

the approved land use plan terms and conditions , as required by CFR 1610.5. Examples of such

laws and plans include the federa l Endangered Species Act, the Ca lifornia Desert Protection Act,

the California Desert Conservati on Area Plan and related tiered pl ans( e.g. the Yuha Basin ACEC

Management Plan, Yuha Desert Habitat Manage ment Plan, Yuha Desert Management Plan,

Imperial San Dunes Recreation Area Manage ment Plan (RAMP), Algodones Dunes Habitate

Management Plan, Flat-tailed Ho rned Lizard Rangewide Strategy and Recovery Plan for Bighorn

Sheep in the Peninsular Ranges, CA).

BLM also must meet the requirements of NEPA fo r its projects. BLM is the appropriate lead

agency for both NEPA and conformity determ inations for dust control projects on BLM lands;

mandating Rule 804 and 805 requirements without cons ideration of NEPA and conformity issues

could unnecessarily involve ICAP CD in these issues and poten tially delay implementation of

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -20- 

# proposed dust control programs. Mandating PR 804 and 805 could also put BLM in the position of

either violating an ICAPCD rule or potentia lly requiring a finding of overriding concerns for a

given Environmental Assessment. Furthermore, a ny action on the use of the BLM lands has been

highly litigious. Were ICAPCD to unilaterally impose requirement s on BLM, it is possible that

litigation and a temporary suspension of those rules while the litigat ion is resolved will occur.

Thus, proposed Regulation VIII establishes a separa te control program for the BLM lands, rather

than imposing general Regulation VIII requirements on them on a dust source by dust source basis.

ICAPCD believes that this is the most appropria te and expeditious way to reduce emissions from

federal sources.

ICAPCD and BLM have worked together on pr evious dust control programs, including the

inclusion of PM 10 

# control measures in the RA MP. BLM has also included PM 10 

# prevention and

mitigation measures based on its Environmental Assessment of its road and trail maintenance

activities related to Border Patrol activities. Appendix F is the Environmental Assessment for this

project. It is an example of the detailed envir onmental analysis required for projects on BLM lands

and the use of the NEPA process to identify and implement PM 10 

# prevention and mitigation

measures.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-21-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationGeneral:Visible DustEmissions•Limit visibleemissions to notmore than 20%opacity (PAR800)oAll non-exemptsources (Ref:PAR 800)oConstruction /demolition (deminimissource) (Ref :PR 802,Section E.1)oBulk materials(de minimissource) (Ref :PR 802,Section E.1)oOpen areas(significantsource) (Ref :PR 804,Section E.1)oUnpaved roadsand trafficareas(significantsource) (Ref :PR 805,Section E.1)Test methods,including for unpavedroad traffic in App. Aand B (PAR800, G)•Limit visibleemissions to notmore than 20%opacity (Ref:R8021, Sect. 5.0;R8031, Sect 5.0;R8041, Sect. 5.7.2;R8051, Sect. 5.0;R8061, Sect. 5.2;R8071, Sect. 5.1;and 8081, Sect.5.0)•Opacity testmethods, includingfor unpaved roadtraffic. (Ref:R8011, AppendixA, Sections 1 and2)•No visibleemissions acrossproperty line.(Ref: R403(d)(1))•Limit visibleemissions to notmore than 20%opacity (RefR310, Sect. 301)•Opacity for dustgeneratingactivities basedon minimum 12observations,spaced 15seconds apart(Ref: R310,Section 501.1(a))•Opacity forunpaved parkinglots and unpavedhaul/access roadsbased on sixvehicles, tworeadings pervehicle (Ref:R310, Section501.1 (a) and (b))•Limit visibleemissions to notmore than 20%opacity (Ref:AQR Section91.2.1.4; AQRSection 92.2.1.3;AQR Section93.2.1.5; AQRSection 94.5.3)•Opacity based onsix vehicles, tworeadings pervehicle forunpaved surfacesAnd minimum 12observations,spaced 15seconds apart, forother sources.(Ref AQRSection 91.4.1.1and AQR Section94 AQR Section94.5.3)•Limitconstructionvisible emissionsto not more than100 yards (Ref:AQR Section94.5.2(a))Imperial County is proposingthe same opacity limits and testmethods used in other areas,except South Coast, whichappears less stringent than otherareas.Clark County requires bothopacity limits and a 100-yardvisible emission distance limitfor construction activities.Construction emissions inImperial County are below theDM level, and thus justificationas “most stringent” is notrequired.Imperial County is proposingthe same opacity limits and testmethods used by San JoaquinValley that have been acceptedby EPA as “most stringent” inits May 26, 2004 approval of theSan Joaquin Valley PM10SIP6.6Federal Register Vol. 69, No. 102; p.30035; May 26, 2004.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-22-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationGeneral:Definition ofStabilizedSurface•A surface isconsidered to bestabilized if itmeets at least oneof the followingconditionsspecified in belowor as determinedby test methodsoutline inAppendix B.1. Visible crust; or2. Thresholdfrictionalvelocity of 100cm/sec orgreater; or3. Flat vegetativecover of at least50% that isattached orrootedvegetation; orunattachedvegetativedebris lying onthe surface witha predominanthorizontalorientation (notsubject to windmovement); or4. Standingvegetativecover over 30%•Any disturbedsurface that isresistant to windblown fugitive dustand meets at leastone of thefollowingconditions:1. A visible crust2. A thresholdfrictionvelocity of 100cm/sec orgreater3. A vegetativecover of atleast 50% thatis attached orrooted4. Unattachedhorizontalvegetativecover of atleast 50% andwindmovementresistant5. Vertical,rootedvegetationwith at least30% cover, or10% coverwhere the soilthreshold•Stabilizedsurface meansany previouslydisturbed surfacearea or openstorage pilewhich, throughthe application ofdustsuppressants,shows visual orother evidence ofsurface crustingand is resistant towind driven•Fugitive dust andis demonstratedto be stabilized;(Ref: R403,(C)(28))•Must meet atleast one of thefollowingstandards:1. Maintain avisible crust2. Maintain athresholdfrictionvelocity of 100cm/sec orgreater3. Maintainstanding(rooted,vertical)vegetativecover of atleast 30%, or10% coverwhere the soilthresholdfrictionvelocity is atleast 43 cm/sec4. Maintain flat(rooted orhorizontaldebris notsubject to windmovement) ofat least 50%5. Maintain acover of atleast 10% with•Stabilizationstandards:1. Establishvisible crust2. Establishcover of atleast 20% withnon-erodiblematerials3. Establish soilthresholdfrictionvelocity of atleast 100cm/sec4. Comply withspeciallyapprovedalternativemethodImperial County is proposingthe same stabilized surfacedefinition and requirements asused in the San Joaquin Valley,which is comparable to therequirements used in all otherareas, except South Coast.The exception is that ClarkCounty has established a morestringent requirement if nonerodible materials are used toestablish a stabilized surface,namely, that a more restrictive20% minimum covering(compared to 10% in SanJoaquin Valley, MaricopaCounty and proposed ICRegulation VIII) is required.However, inclusion of a 20%minimum non-erodible materialcoverage as a control option inClark County does not mean itsinclusion is necessary forRegulation VIII to bedemonstrated as BACM for thiscategory. Clark County’s limitwas based on local observationsat areas where the soil wassignificantly pulverized as theresult of significant amounts oftraffic.7Imperial County doesnot have similar areasexperiencing such high levels ofgrowth and commuters7September 26, 2005 telephone conversation with Rodney Langston, Clark County Department of Air Quality Management.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-23-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / Justificationthat is attachedor rooted5. A standingvegetativecover of at least10% that isattached orrooted with apredominateverticalorientationwhere the TFVis at least 43centimeters persecond whencorrected fornon-erodibleelements6. A surfacegreater than orequal to 10% ofnon-erodibleelements suchas rocks, stones,or hard-packedclumps of soil(Ref: 800 C.28)Test methods:Test methods inAppendix A and Bshall be used todetermine compliancewith the RegulationVIII rules (RefPAR800, Section G)frictionvelocity is atleast 43cm/sec6. A surface thatis at least 10%covered withnon-erodiblematerials (Ref:R8011,Section 3.58)non-erodiblematerials6. Comply withspeciallyapprovedalternativemethod(Ref: R310,Section 302.3)“trailblazing” unpaved roadsacross open areas. Thus, thislimit was based on specificClark County conditions andshould not be applied toImperial County.Taken together, the applicablelimits and requirements in thedefinition of a stabilized surfaceprovide equivalent stringencyand can be considered asstringent as the most stringentlimits and requirements. Theexact same provisions in SanJoaquin Valley were approvedas BACM by EPA8in 2004.8Federal Register Vol. 69, No. 102, p.30035, May 26, 2004.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-24-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationUnpavedRoads:Applicability•Unpaved Haul/Access Roads:All roads (Ref:PR805, SectionE.1)•Unpaved Roads:50 or moreaverage dailyvehicle trips (Ref:PR805, SectionE.2)•Canal Roads: 20or more ADT(Ref: PR805,Section E.4)(The implementationschedule for city andcounty roads isdiscussed in the nextsection, UnpavedRoads: ControlRequirements.)•26 annual averagevehicle daily tripsor more (Ref:R8061, Section5.2.1)(The implementationschedule for city andcounty roads isdiscussed in the nextsection, UnpavedRoads: ControlRequirements.)•For meetingstandards of rule:omore than 50’wide at allpoints, oroare not within25’ of propertyline, oromore than 20vehicle trips perday (Ref:R403(g)(2)(B)(iii))•For treatingunpaved roads:All roads greater thanthe average ADT ofall unpaved roadswithin its jurisdiction,up to a set number ofmiles by 2006 (Ref:R1186(d)(4))•150 vehicles ormore per day(Ref: R310.01,Section 304)•For new unpavedroads, there is noVDT limit (RefAQR Section91.2.1)•For existingunpaved roads(prior to June 22,2000), the controlmeasures apply toroads with 150 ormore vehicles perday.Imperial County’s limit is basedon 50 or greater ADVT. TheImperial County 50 ADVT ormore limit is more stringent thaneither Maricopa County of ClarkCounty. Both Maricopa andClark County have a significantnumber of unpaved roads withgreater than 150 ADT; hencetheir rules target those roads.The provisions of the SouthCoast rule, tied to average levelsof VDT, is generally lessrestrictive than in otherjurisdictions.The proposed ADT limit forunpaved city and county roadsin IC Regulation VIII is lessstringent than SJV’s limit of 26ADVT. However, thepercentage of unpaved city /county roads with greater than26 ADT in San Joaquin Valleyis 12% (90 out of 750 miles)9compared to 16% of ImperialCounty roads withgreater than50 ADT (217 out of 1361.5miles). Thus, proposedRegulation VIII is the moststringent. (A comparison ofimplementation schedulerequirements is presented in thenext row, Unpaved RoadRequirements.9EPA’s Technical Support Document for the San Joaquin Valley, California 2003 PM10Plan and 2003 PM10Plan Amendments., p. 31, January 27, 2004.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-25-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationOnly Imperial County sets aseparate, lower threshold forcanal roads, and 20 ADT isbelow any other unpaved roadthreshold. Proposed RegulationVIII is the most stringent.UnpavedRoads:ControlRequirements•For roads with 50ADVT or moreand canal roadswith 20 or greaterADVT, limit VDEto 20% opacityand comply withthe requirementsof a stabilizedunpaved roadsurface byapplication and/ormaintenance of atleast one of thefollowing controlrequirements(Ref: PR805,Section E.2, E.4):a) Pave (SectionF.1.a)b) Apply chemicalstabilization (,Section F.1.b)c) Apply andmaintaingravel, asphalt,or othermaterial of low•For unpaved roadswith greater than26 annual averagevehicle trips perday, limit VDE to20% opacity andimplement at leastone of thefollowing controlmeasures:a) apply waterb) apply uniformlayer ofwashed gravelc) applychemical/organic dustsuppressantd) use vegetativematerialse) pavef) use any otherapprovedmethod tolimit VDE to20% opacityand meets thecondition of a•Annually treatunpaved publicroads beginning in1998 andcontinuing foreach of 8 yearsthereafter byimplementing oneof the following(Ref:R1186(d)(4)):a) Pave at leastone mile withtypicalroadwaymaterial (Ref:ibid,(d)(4)(A))b) Applychemicalstabilizers toat least twomiles tomaintainstabilizedsurface(Ref: ibid,(B))•For 150 vehicles ormore per day,implement at leastone of thefollowing BACM(Ref: R310.01,Section 304):a) Paveb) Apply dustsuppressantsc) Uniformlyapply andmaintainsurface gravel(Ref: ibid,Section 304.1)•For existingroads, BACM, asabove, must beimplemented by:a) June 10, 2000for more than250 vehicletripsb) June 10, 2004for more than150 vehicletrips•Implement onecontrol measureon 1/3 of unpavedroads with 150+VDT by June 1,2001 (Ref: AQRSection91.2.1.1(a))•Implement onecontrol measureon 2/3 of unpavedroads with 150+VDT by June 1,2002 (Ref: ibid,(b))•Implement onecontrol measureon all unpavedroads with 150+VDT by June 1,2003 (Ref: ibid,(c))•For any unpavedroad with newlyfound levels of150+ VDT,implement onecontrol measureProposed Regulation VIII andrules in all areas except SouthCoast require compliance withthe 20% opacity standard;Proposed Regulation VIII is asstringent as the most stringentfor this requirement. Inaddition, all areas except SouthCoast specify theimplementation of at least onecontrol requirement to complywith the requirements of astabilized surface. Clark andMaricopa County do not allowwatering as a control option, butonly require implementation onroads with greater than 150ADT. As noted by EPA10, theinclusion of a control option orrequirement does not mean it isnecessary for a proposedregulation to meet BACM, aslong as other applicable limitscombine provide adequatestringency. In this case, theapplicability and controlrequirements combine provideadequate stringency.10Federal Register Vol. 69, No. 102, p.30019, May 26, 2004.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-26-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / Justificationsilt content of adepth of 3 ormore inches(Section F.1.c)d) Apply waterone ore moretimes daily(Section F.1.d)e) Permanent roadclosure(Section F.1.e)f) Restrictunauthorizedvehicle access(Ref: PR805,Section F.1.f)g) Any othermethod thatlimits VDE to20% opacityand meetsconditions of astabilizedunpaved road(Section F.1.g)•Within an urbanarea, constructionof a new unpavedroad isprohibited, unlessit meets thedefinition of aTemporaryUnpaved Road.•Cities and thestabilizedunpaved road(Ref: R8061,Section 5.2.1)•As option to above,obtain FugitivePM10ManagementPlan (Ref: ibid,Section 5.2.1) withspecificrequirements.•Within an urbanarea, constructionof a new unpavedroad is prohibited,unless it meets thedefinition of atemporary unpavedRoad.•Cities and theCounty shall treatan average of 20%of applicable roadsper year form 2006through 2010,to acap of 5 miles peryear perjurisdiction. Astatement offinancial hardshipcan be submitted ifa jurisdictioncannot afford tomeet therequirements of thisc) Speed control(15 mph) onat least threemiles of roadsurface:(Ref: ibid,304.2)•BACM must meetthe followingstandards:a) Limit VDE to20% opacityb) Do not equalor exceed0.33 oz/ft2,orc) Do notexceed 6%silt content(Ref: ibid,304.3)within 365 days(Ref: ibid, (d))•For unpaved roadswith less than 150VDT, maintainstabilized surfacestandards within365 days ofdetermination ofnon-stabilizedsurface (Note: nota SIP measure)•No new unpavedroads are to beconstructed afterJune 22, 2000(Ref: AQRSection 91.2.1.2)•Applicable controlmeasures are asfollows:a) Paveb) Apply dustpalliatives tomeet stab.standards•Stabilizationstandards:a) Limit VDE to20% opacityb) Do not equal orexceed 0.33oz/ft2, orc) Do not exceed6% silt contentThe control options for existingunpaved roads in ProposedRegulation VIII and in SanJoaquin Valley’s regulations arethe same, and thus equallystringent (although as seenabove, proposed Regulation VIIIapplies to a greater percentageand absolute mileage of unpavedroads).Although the complianceschedule for city and countyroads appears more stringent forSan Joaquin (20% per year), thatonly equates to 18 miles peryear, compared to almost 22miles per year for ImperialCounty (10% of 217 miles). Inaddition, San Joaquin caps at 5the number of miles that requiretreatment per year per urbanareas. San Joaquin also allowscities and/or counties to submit astatement of financial hardshipif they cannot meet the rulerequirements. The San JoaquinValley regulations have beenapproved as BACM by EPA11.Proposed Regulation VIII is asstringent as the most stringentrequirements in any serious nonattainment area.11Federal Register Vol. 69, No. 102, p.30035, May 26, 2004.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-27-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationCounty shallcomply withSection E.2 bytreating anaverage of 10%of applicableroads per yearform 2006through2015.(Ref:PR805, SectionE.7)section. (RefR8061, Section5.2.3).(Ref: ibid,91.2.1.4)Proposed Regulation VIIIprohibits the construction ofnew unpaved roads in urbanareas. This is as stringent as theSan Joaquin Valley and ClarkCounty regulations. (ClarkCounty regulations are only ineffect in the non-attainmentarea, which is predominantlyurban, and not in thesurrounding rural and federallands. Hence, the prohibition onnew unpaved roads is essentiallya prohibition on new unpavedroads in urban areas.)Unpaved Lots:Applicability•Unpaved trafficareas larger thanone (1) acre andwith 75 or moreaverage vehicletrips per day shallcomply with oneor more of therequirements ofSection F.3 so asto limit VDE to20% opacity(Ref: PR805,Section E.4)•Areas withAADT of 50 ormore (Ref:R8071, Section4.1)•Agriculturalsources exemptfrom Rule 8081are also exemptfrom R8071.(Note: South Coastdoes not have rulelanguage specifyingthis category. It ispresumed that Rule403 provisions foreither unpaved roads,or disturbed surfaceareas would apply.)•Over 100vehicles enteringor parking (Ref:R310.01,Section 303)•No minimumvehicle limitspecified forparking lots. (Ref:AQR, Section92.2.1)•No minimumvehicle limitspecified forstaging areas (Ref:AQR Section 94Handbook, CST17)Clark County has no minimumvehicle limit for parking lots orstaging areas. Maricopa has a100 vehicle threshold. SanJoaquin exempts traffic areaswith less than 50 annual averagedaily trips and agriculturaltraffic area sources exempt fromR8071 (e.g., traffic area lessthan 1.0 acre and more than onemile from an urban area, or withless than 50 AADT or less than150 VDT if intermittently used).EPA has adjudged the SanJoaquin rule as BACM12basedon the adequacy of their costeffectiveness analyses ofpotential lower thresholds.Proposed Regulation VIII has a12EPA’s Technical Support Document for the San Joaquin Valley, California 2003 PM10Plan and 2003 PM10Plan Amendments, p. 34-5, January 27, 2004Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-28-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / Justificationhigher threshold for ADVT thanSan Joaquin and a 1 acre sizethreshold. ICAPCD isconducting additional surveywork and will prepare a costeffectiveness analysis to justifythe proposed thresholds. If theanalysis indicates that morestringent thresholds are costeffective, amendments to PR805will be prepared. Please seeAppendix C for more discussionabout Imperial County unpavedtraffic areas.(Although agricultural unpavedtraffic areas are exempt from PR805, any size traffic area for anagricultural operation with morethan 40 acres total mustimplement controls, per PR806.)Unpaved Lots:RequirementsFor unpaved trafficareas larger than one(1) acre and with 75or more averagevehicle trips per dayshall comply with oneor more of therequirements ofSection F.3 (listedbelow) so as to limitVDE to 20% opacity:•Pave or (Ref:PR805, Section•For days with 50or more vehicletrips, limit VDE to20% opacity andimplement at leastone of thefollowing controlmeasures:oapply wateroapply uniformlayer ofwashed graveloapply(No specific rulelanguage for thiscategory. Seemeasures for“Unpaved Roads” forpresumed applicableBACM.)•If utilized less than35 days per year,use one offollowing:a) Apply dustsuppressantsto maintainstabilizedsurfaceb) Apply andmaintaingravel tomaintain•For unpavedparking lots, useone of following:a) Paveb) Apply dustpalliatives tomaintainstabilizedsurfacec) Apply dustpalliatives totravel lanes,and applyMaricopa County requires thestabilization or paving of alltraffic areas, regardless of usage.Watering is not an option.Clark County requires thepaving or stabilization ofunpaved traffic areas, unless thearea is only used infrequently.In that case, stabilization onlyhas to occur during use times.Watering is not an option.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-29-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationF.3.a)•Apply chemicalstabilizers (Ref:PR805, SectionF.3.b)•Apply andmaintain gravel,recrushed/recycledasphalt or othermaterial of low siltcontent to a depthgreater than 3inches (Ref:PR805, SectionF.3.c)•Wetting. Applywater one or moretimes daily (Ref:PR805, SectionF.3.d)chemical/organic dustsuppressantouse vegetativematerialsopaveouse any othermethod to limitVDE to 20%opacity (Ref:R8071, Section5.1.1)•For days with 100or more vehicletrips, as above andcomply withrequirements forstabilized surface(Ref: ibid, Section5.1.2)•On each day that25 or more VDTwith 3 or moreaxles will occuron an unpavedvehicle/equipmenttraffic area,specialrequirements(Ref: R8071,Section 5.1.3).•On each day whena special eventwill result in1,000 or morevehicles, specialrequirements.stabilizedsurface(Ref:R310.01,Section 303,and 303.1)•If utilized at least35 days per year:a) Add option, toabove, to pave(Ref: ibid; alsoR310, Table 1,1B,2B,3B)gravel to adepth of twoinches in theparking areasto maintainstabilizedsurface (Ref:AQR Section92.2.1 and92.2.1.2)•If parking lot isused intermittently,less than 35 daysper year, and thelot was in existenceprior to June 22,then applicationmay be limited toperiod of use (Ref;ibid, 92.2.1 and92.2.1.1)•For staging areas:oLimit size ofstaging areas(Ref AQR,Section 94Handbook,CST 17-1)oApply water(Ref: ibid, CST17-2)oApply dustpalliative (Ref:ibid, CST 17-3)oLimit vehiclespeeds to 15Proposed Regulation VIII andSan Joaquin Valley rules allowthe use of daily watering as acontrol option; thus, RegulationVIII includes an option that isless stringent, based on therelative control effectiveness ofwatering compared tostabilization, gravelling andpaving. However, proposedRegulation VIII still requirescompliance with the opacitylimitHowever, in SJV for sites ondays with more than 100 trips,the surface must comply withstabilized surface requirements,and for areas on days with morethan 25 VDT from vehicles with3 or more axles or if over 1000vehicles are anticipated, thereare special control requirements(generally re-application ofstabilizers or water) for thosedays. Imperial County commitsto assessing the need and costeffectiveness of these specificsingle day provisions andpreparing amendments to PR805, if necessary.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-30-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / Justification(Ref: R8071,Section 5.1.4).•As option toabove, obtainFugitive PM10Management Plan(Ref: ibid, Section5.2.1, 5.2.2, and5.2.3)mph (Ref: ibid,CST 17-4)oLimit ingressand egresspoints (Ref:ibid, CST 17-5)UnpavedRoads: CanalRoads•For Canal Roadswith 20 or moreADT (Ref: PR805,Section E.3)a) Stock TriploidGrass carp incanals toreducemaintenancetrips or (Ref:PR805, SectionF.2.a)b) Install remotecontrol deliverygates or (Ref:PR805, SectionF.2.a)c) Implement Siltremovalprogram todelay gradingof spoil piles or(Ref: PR805,Section F.2.a)d) Permanent roadclosure or (Ref:PR805, Section(No requirementsspecified.)(No requirementsspecified.)(No requirementsspecified.)(No requirementsspecified.)Canal roads are unpaved roadsused by the Imperial IrrigationDistrict to maintain theirrigation canal network. SanJoaquin has identified privatecanal roads in its inventory butdoes not anticipate that theseprivate canal roads have trafficlevels that meet the 26 ADTthreshold for unpaved roadcontrols and does not specifyadditional canal roadrequirements such as the ones inproposed Regulation VIII.Thus, these requirements are themost stringent for this source.(NOTE: These requirements arein addition to the generalunpaved road requirements forunpaved roads that canal roadsare also subject to. SeeUnpaved Roads: Applicabilityand Unpaved Roads: ControlRequirements above.)Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-31-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationF.2.a)e) Convert opencanals topipeline or(Ref: PR805,Section F.2.a)f) Line canals toeliminatemaintenancefor silt/weedcontrol or (Ref:PR805, SectionF.2.a)g) Initiate canalbank surfacemaintenance(Ref: PR805,Section F.2.a)Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-32-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationDisturbed OpenAreas:Applicability•0.5 acres or largerin urban areas, or3.0 acres or morein rural areas; andcontains at least1,000 square feetof disturbedsurface area (Ref:PR804, Section B)•This rule appliesto any open areahaving 0.5 acresor more withinurban areas, or3.0 acres or morewithin ruralareas; andcontains at least1000 square feetof disturbedsurface area(R8051, Section2.0).•No limitRule 310, Section 102exempts disturbedopen areas which arenot located at sourcesrequiring “any permitunder these rules.”However, most openareas will not haveneed for permits.Section 303 requires adust control plan(presumed to be whatis referred to inSection 102 as a“permit”), for allsources that involveearthmovingoperations of 0.10acres or greater.Since soildisturbances canoccur for reasonsother thanearthmoving, forexample, off-roadvehicle traverses, itappears that manydisturbed open areas,vacant lots, etc, maybe exempt underthese rules.•5,000 square feetor larger (nonag) (Ref: AQRSection 90.1.2and 90.2.1)The most stringent applicabilityis South Coast Rule 403, whichhas no minimal level (althoughthe related control requirementsare less stringent than otherserious non-attainment areas)Clark County AQR Section 90which has a 5,000 square foot(approx. 1/9 acre) minimumlevel for all types of open areasand vacant lots. ImperialCounty and SJV applicabilitythresholds are the same. EPAadjudged13the SJV thresholds asmeeting the stringency test andqualifying for BACM since over98% of the total parcel acreageis in parcels of 3 acres orgreater. For Imperial County,more than 99.5% of the totalparcel acreage is in parcels of 3acres or greater.14Hence,proposed Regulation VIIIapplicability threshold is morestringent than SJV’sapplicability threshold, whichhas already been determined tobe BACM.13EPA’s Technical Support Document for the San Joaquin Valley, California 2003 PM10Plan and 2003 PM10Plan Amendments., p. 37-38, January 27, 2004.14Imperial County Assessors Office parcel data, 2001.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-33-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationDisturbed OpenAreas:ControlMeasuresUse one or more ofthe followingmeasures to complywith the stabilizedsurface requirementsso as to limit openareas to VDE of 20%opacity (Ref: PR804,Section E.1)•Apply andmaintain water ordust suppressant toall unvegetatedareas (Ref: PR804,Section F.1.a)•Establishvegetation on allpreviouslydisturbed areas(Ref: PR804,Section F.1.b)•Pave, apply gravel,chemicalstabilizers/suppressants (Ref: PR804,Section F.1.c)•Preventunauthorizedvehicle access byposting “NoTrespassing” signsor installingphysical barriers toprevent access(Ref: PR804,Use one or more ofthe followingmeasures to complywith the stabilizedsurface requirementsso as to limit openareas to VDE of 20%opacity (Ref: Rule8051, Section 5.0)•Apply water/dustsuppressants tounvegetated areassufficient to limitVDE to 20%opacity (Ref:R8051, Table8051-1, A1)•Establishvegetation to limitVDE to 20%opacity (Ref: ibid,A2)•Pave, applygravel, applystabilizers to limitVDE to 20%opacity (Ref: ibid,A3)•Upon evidence oftrespass, post “notrespass” signs orinstall barriers toprevent access toarea (Ref: ibid, B)•Apply chemicalstabilizers (Ref:R403 Handbook,BACM (Q))•Water withsufficientfrequency toestablish a surfacecrust (Ref: ibid,(R))•Establish(drought-resistant)vegetation asquickly aspossible (Ref:ibid, (T))•Restore vegetativeground cover andsoil characteristicssimilar to nativeConditions (Ref:R310, Table 1, 1E)•Pave, apply gravel,apply stabilizer tomeet stabilizedstandards (Ref:ibid, 2E)•Establishvegetation to meetstabilized standards(Ref: ibid, 3E)•Stabilizedstandards, one ofthe following (Ref:R310, Section302.3):•Upon evidence ofsoil disturbance bymotor vehicles,prevent trespass,parking, and accessby installingbarriers, curbs,fences, gates,posts, signs,shrubs, and trees.(Ref: AQR Section90.2.1.1(a))•Apply gravel orchemicalstabilizers to meetone of stabilizationstandards (Ref:ibid, (b))•Stabilizationstandards – seeGeneral: Definitionof a StabilizedSurface above(Ref: AQR Section90.2.1.2)Proposed Regulation VIII andSJV requirements are identical.Maricopa County and ClarkCounty have established soilstabilization standards fordetermining the effectiveness ofthe control measures. (Withrespect to the stabilizationstandards, see General:Definition of a StabilizedSurface above.) EPA hasapproved the SJV regulations asBACM15, and the proposedRegulation VIII requirementsare as stringent as the moststringent requirements in otherserious non-attainment areas.15Federal Register Vol. 69, No. 102, p.30035, May 26, 2004.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-34-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / JustificationSection E.2)Disturbed OpenAreas:WindblownThere are no specificexemptions for windevents in theproposed RegulationVIII amendments,thus no requirementsfor windblown dustare specified.However, opacity andstabilized surfacerequirements remain,independent of windspeed.(No specificrequirements)As contingencymeasures for a highwind exemption fromcertain rulerequirements:•If inactive, applywater or chemicalstabilizers tomaintain a stabilizedsurface for sixmonths (Ref: R403,Table 3, 0B)•Apply chemicalstabilizers prior towind event (Ref:ibid, 1B)•Apply water 3 to 4times per day (Ref:ibid, 2B)•Establish vegetativeground cover within21 days after activeoperations have•Apply gravel ordust suppressants(Ref: R310, Table2, 1B)•Apply water 3 timesper day; if evidenceof wind drivenfugitive dust,increase watering to4 times per day(Ref: ibid, 2B)(No specific windrequirements,however, the generalrequirements fordisturbed surfaceareas includeprovisions which areintended to reducewindblown dust:•Prevent access tolimit soildisturbance (Ref:AQR Section 94Handbook, CST11)•Stabilize soil, usingdust palliative orvegetation tomaintain stabilizedsurface(Ref: ibid, CST 11-4 and 11-5)•Pave or applyThere are no specificexemptions for wind events inthe proposed Regulation VIIIamendments. This is the moststringent requirement, sincethere are not exemptions fromRegulation VIII provisionsbecause of high winds.It should be noted that forconstruction activities (whichare not a significant source),there is an exemption from the20% opacity requirement(PR801, Section D.2). Toqualify for the exemption, theoperator must either ceaseoperations, water or apply dustsuppressants once per hour, ormaintain a 12% soil moisturecontent by watering.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-35-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / Justificationceased (Ref: ibid,3B)surface rock tomaintain stabilizedsurface (Ref: ibid,CST 11-6))AgriculturalSources:CMPsFor owner/operatorsof commercial farmson sites greater thanor equal to 40 acres,implement at leastone of the followingin each category:•Land preparationand cultivation(Ref: PR806,Section E.1):a. alternative tillb. bed/row sizespacingc. chemical/fertigationd. combinedoperationse. conservationirrigationf. conservationtillageg. cover cropsh. equipmentchangesi. fallowing landj. pest controlk. mulchingl. night farmingm. nonSJVAPCD Rule 4550requires the submittalof a conservationmanagement plan forsites with more than100 acres with 1conservationmanagement practice(CMP) for eachcategory:•Land preparationand cultivation:same as ImperialCounty withaddition of floormanagement (nutcrops), time ofplanting andtransplanting (somevegetable crops)options.•Harvest: same asImperial Countywith addition ofcontinuoustray/D.O.V. (dryfruit crops),fallowing land; andfloor management(nut crops) options.For agriculturaloperations within theSouth Coast AirBasin, with combineddisturbed surface areaof 10 acres or more,the standards of Rule403 apply after July1, 1999 unless BestManagementPractices asdelineated in the Rule403 AgriculturalHandbook areimplemented. (Ref:R403(h)(1))Best ManagementPractices as describedin the AgriculturalHandbook are asfollows:a) Activeconservationpracticesb) Inactiveconservationpracticesc) Farm yard areasd) TrackoutIn May 2000, theAgricultural BMPCommittee adoptedthe agricultural PM10general permit, whichbecame effective byrule on May 12, 2000(ArizonaAdministrative Code[AAC], R18-2- 610and 611). TheCommittee identified34 BMPs that focuson feasible, effective,and common sensepractices whileminimizing negativeeconomic impacts onlocal agriculture.(These BMPs werebased on the BMP’sin the South CoastAgriculturalHandbook). Thegeneral permitrequires that acommercial farmerimplement at leastone BMP to controlPM10for each of the(No requirements forthis source)ICAPCD CMPs apply to farmsites with 40 or more acres,which represent 90% of farmland in Imperial County. Bycomparison, San Joaquin Valleyrequires CMPs at site greaterthan 100 acres, which representsabout 91% of farm land in SanJoaquin Valley. Thus, the farmsite limit is equally stringentcompared to the most stringentthreshold.The proposed ICAPCD CMPrequirements are similar to therequirements in San JoaquinValley, Maricopa County andSouth Coast, and are directlybased on the San Joaquin Valleyrequirements that were approvedby EPA16as meeting the BACMrequirements. The ProposedImperial County requirementsare specifically based on the SanJoaquin requirements and are ofsimilar stringency; thus, they areas stringent as the most stringentrequirements for this source.16Federal Register Vol. 69, No. 102, p.30035, May 26, 2004.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-36-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / Justificationtillage/chemicaltillagen. organicpracticeso. precisionfarmingp. transgeniccrops•Harvesting (Ref:PR806, SectionE.2):a. bailing/largebailsb. combinedoperationsc. equipmentchangesd. green chope. hand harvestingf. fallowing landg. nigh harvestingh. no burningi. pre-harvestingsoil preparationj. shed packingk. shuttle system /large carrier•Unpaved farmroads and trafficareas (Ref: PR806,Section E.3,4):a. chips/mulches,organicmaterials,polymers, roadoil and sandb. gravel•Unpaved farmroads and trafficareas: same asImperial Countywith the addition ofmechanical pruning(tree and vinecrops) option.conservationpracticese) Unpaved roadconservationpracticesf) Storage pileconservationpractices•(Ref: Guide toAgricultural PM10Dust ControlPractices, datedJune 1999)following threecategories: tillage andharvest, noncropland, andcropland. The generalpermit requires acommercial farmer tocomply by December31, 2001.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-37-Table 4-2. Dust Control Source Categories For Sources Above the DM LevelCONTROLCATEGORYImperial San Joaquin Valley South Coast MaricopaCounty Clark County Discussion / Justificationc. pavingd. restrictedaccesse. speed limitf. track-outcontrolg. waterh. wind barrier

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -38- 

# Comparative Analysis for Sources With Emissions Less Than the DM Level

Sources with emissions below the DM level do not need to be included in the BACM determination.

Table 4-3 presents the rule source categories for these sources with emissions below the DM level.

For information purposes only, Appendix D presents a comparative analysis for these sources.

Table 4-3. Dust Control Source Categories For Sources Below the DM Limit



# RULE SOURCE CATEGO RY CONTROL CATEGORY

Construction Visible Dust Emissions

Construction Demolition

Construction Pre-Earthmoving

Construction Earthmoving

Construction Demolition

Construction Inactive Disturbed Land

Construction Windblown

Construction Dust Plan Applicability

Construction Dust Plan Requirements

Bulk Materials Handling/Storage

Bulk Materials Transport

Bulk Materials Outdoor Chute/Conveyor

Bulk Materials Windblown

Carryout/Trackout Removal

Carryout/Trackout Prevention

Carryout/Trackout Clean-Up Methods

Paved Road Dust New/Modified Roads

Paved Road Dust Erosion Clean-Up

Paved Road Dust Street Sweeping

Cattle feedlots Requirements

Weed Abatement Requirements

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -39- 

# 5. IMPACT ANALYSIS

This section presents information about the emi ssion reductions, cost and co st-effectiveness of the

proposed to Regulation VIII amendments. This report relies on previous analysis of BACM

effectiveness, costs, and cost-effectiv eness prepared for the 1993 SIP for PM 10 

# in the Imperial

Valley 17 

# rule. It also relies on information is ta ken from the October 18, 2004 CARB staff report

entitled “Proposed List of Measures to Reduce Particulate Matter – PM 10 

# and PM 2.5 

# ,” and the April

28, 2003 SJVAPCD Appendix G to their 2003 PM 10 

# Plan, entitled “Best Available Control

Measures / Technology and Reasonably Available Control Measures / Te chnology Demonstration

for Sources of PM 10 

# and PM 10 

# Precursors in the San Joaquin Valley.” (The CARB staff report

summarizes PM 10 

# control measures adopted in California and their repo rted cost-effectiveness.)

Emission reduction and cost estimates are provide d for all proposed Regulation VIII rules. As

noted in Chapter 1, this BACM analysis has not been prepared as part of the SIP development

process.

Control Effectiveness and Cost Information

As noted above, the control effectiveness of meas ures within proposed Regulation VIII are based on

previously published estimates, including those used in the 1993 Imperial Valley PM 10 

# SIP, the

2003 San Joaquin Valley PM 10 

# SIP and, where necessary, other serious PM 10 

# non-attainment area

SIPs and related technical documents. Table 5- 1 summarizes, for each proposed Regulation VIII

rule, estimated emissions from sources covered by the proposed rule, th e percentage of those

emissions that are subject to cont rol requirements, the composite co ntrol factor for those controls,

and the estimated emission reduc tions at full implementation. Cost information is based on

information from the 1993 Imperial Valley PM 10 

# SIP, the 2003 San Joaquin Valley PM 10 

# SIP 18 

# and

the latest information from Imperial County publ ic works department. The following subsections

present the input information and assumptions used in Table 5-1

Table 5-1. Proposed Regulation VIII Emission Reduction Summary

Proposed Rule Emissions

(tons/day) Applicability

(percent) Composite

Control Factor Emission

Reductions

801 (Construction) 1.91 100 0.12 0.23

802(Bulk Materials) 2.61 10 0.5 0.13

803 (Track-out) 4.09 18.4 0.6 0.45

17 

# ICAPCD, “State Implementation Plan for PM 10 

# in the Imperial Valley,” Final, adopted September 28, 1993.

18 

# Appendix G, BACM/T and RACM/T Demonstration for Sources of PM 10 

# and PM 10 

# Precursors in the San Joaquin

Valley Air Basin. SJVAPCD 2003 PM 10 

# SIP. SJVAPCD. April 2003.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -40- 

# Table 5-1. Proposed Regulation VIII Emission Reduction Summary

Proposed Rule Emissions

(tons/day) Applicability

(percent) Composite

Control Factor Emission

Reductions

804 (Open Areas) 163.36 1 0.7 1.14

805 (Non-Farm

Unpaved Roads) 84.53 20 0.6 10.09

805 (Paved Roads) 4.09 1 0.8 0.03

806 (CMPs) 25.35 see below see below 4.16

TOTAL 281.85 16.23



# There is no current information on which control opti ons will be used by sources to comply with the

proposed rules, so information on control options in each proposed rule is presented in the

following subsections. The exception is the trea tment of unpaved roads by Imperial County to

comply with PR 805; specific cost information is provided for the treatment of applicable roads.

PR 801: Construction

PR 801 applies to any construction or other earth moving activities. Only construction at existing

single family homes is exempt, so the rule a pplies to all new construction emissions. PR 801

upgrades the RACM controls in previous Rule 800 to BACM controls consistent with requirements

in other serious non-attainment areas. Emission estimates for c onstruction already include the

effect of basic RACM controls, su ch as watering. BACM upgrades wi ll require additional watering

and/or stabilizing during and af ter construction activities. As noted in the South Coast 1997

AQMP, such BACM upgrades provide an additi onal control efficiency of approximately 12%,

mostly from additional water and/or stabilizing during and after construc tion or other earthmoving

activities. Overall reduct ions from PR 801 are estimated at 0.23 tons/day.

Estimated costs for certain constr uction-related controls include: additional use of water trucks

($3,152 per 40 acre project) 19 

# ; water sprinkler ($30 per acre); and dust control plans and related

costs ($112/acre) 20 

# ; . Actual costs for compliance is subjec t to the control opti ons used by the site

and the level of dust cont rol currently practiced.

PR 802: Bulk Materials

PR 802 applies to the handling, stor age, and transport of bulk materi als. There is not an explicit

inventory category for bulk materi als, although it can be assumed that the majority of handling,

storage, and transport of these mate rials occur at mineral processing f acilities and, to some extent, at

19 

# Final BACM Technological and Economic Feasibility Analysis, SJVAPCD 2003 PM 10 

# SIP, April 2003.

20 

# SCAQMD, Rule 403 Final Staff Report, September 1992.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -41- 

# construction sites. It is assumed that 10% of th e emissions from mineral processing facilities are

related to bulk materials. Wetti ng of bulk material piles and transf er points has an estimated control

efficiency of 50%. (San Joaquin estimated a 56 to 81% control efficiency.) Emission reductions

from transfer controls have not been estimate d, but most mineral processing plants are operating

under ICAPCD permits that require control at major transfer points. Overall reductions from PR

801 are estimated at 0.23 tons/day.

Estimated costs for PR 802-related controls include: Truck covers ($900 per truck) 21 

# ; and 3-sided

enclosure ($830 per enclosure) 22



# .

PR 803: Carry-out and Track-out

PR 803 applies to material carried or tracked out onto paved roadwa ys. There is not an explicit

inventory category for track-out, although it can be assumed that a given percentage of the silt

loading on paved road surfaces is from track-out. EPA guidance 23 

# indicates that 46% of paved road

deposition is attributable to mud and dirt car ry-out. In addition, many permanent facilities (e.g.

mineral processing facilities) curr ently implement PR805 track-out cont rols. It is assumed that 40%

of the track-out emissions originate from constr uction and other temporar y sites that have not

previously been using PR805 controls. Thus, the 18% of paved road dust will be affected by new

PR 803 controls. Overall reductions from PR 803 are estimated at 0.45 tons/day.

Estimated costs for PR 803-related controls include: paving access points ($6,000 to $8,500 per

access point) 24 

# ; chemical stabilization ($984) 25 

# ; gravelling ($680 to $1,360 per year per access

point) 26 

# ; and track-out control device ( $3,500 to $4,800 plus maintenance costs) 27



# .

PR 804: Open Areas

PR 804 applies to non-agricultural rural open areas more than 3 acres (rural) or 0.5 acres (urban).

Review of Imperial County parcel data indicates that over 99.5% of parcels are greater than 3 acres

in size. However, 77.5% of Imperial County is de sert and/or scrubland, mu ch of which is under the

control of BLM or other federal agencies. (BLM areas are exempt from Rule 804, but are subject to

dust control plan requirements in PAR 800. Agri cultural areas, which cover 21% of Imperial

County, are subject to PR 806.) For purposes of estimating emission reductions, it is assumed that

the non-BLM desert and scrubland ar eas are not disturbed by man due to their remoteness. It is

assumed that most disturbed land will occur relative ly near the urban areas, which represent 1.5% of

Imperial County. Assuming that up to 2/3rds of th at area could be disturbe d, the applicability is

estimated to be 1% or less. Th e composite control factor is estim ated to be 70% (based on control

efficiencies cited in San Joaquin Valley’s 2003 PM 10 

# SIP). Overall reductions from PR 804 are

estimated at 1.07 tons/day. (It should be noted that the BLM dust contro l plan could result in

additional reductions from this s ource, depending on the extent of BLM areas that are disturbed by

21 

# ICAPCD, “State Implementation Plan for PM 10 

# in the Imperial Valley,” Final, adopted September 28, 1993.

22 

# Final BACM Technological and Economic Feasibility Analysis, SJVAPCD 2003 PM 10 

# SIP, April 2003.

23 

# EPA, Fugitive Dust Background Document and Technical Information Document for Best Available Control

Measures, Document Number EPA-450/2-92-004, Offi ce of Air Quality Planning and Standards, 1992.

24 

# ICAPCD, “State Implementation Plan for PM 10 

# in the Imperial Valley,” Final, adopted September 28, 1993. and

SCAQMD, Rule 403 Final Staff Report, Appendix G, February 1997.

25 

# SCAQMD, Rule 403 Final Staff Report, Appendix G, February 1997.

26 

# Final BACM Technological and Economic Feasibility Analysis, SJVAPCD 2003 PM 10 

# SIP, April 2003.

27 

# .Final BACM Technological and Economic Feasibility Analysis, SJVAPCD 2003 PM 10 

# SIP, April 2003, and

SCAQMD, Rule 403 Final Staff Report, Appendix G, February 1997

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -42- 

# illegal OHV use. There will also be reductions resulting from implementation of the BLM dust

control plan of episodic emi ssions from legal OHV events.)

Estimated costs for PR 804-related controls in clude: dust suppressants ($3,340 per acre); and

signage ($200 per sign). 28



# PR 805: Paved and Unpaved Roads

PR 805 applies to unpaved paved roads. Of th e 7,813 miles of unpaved roads in Imperial County,

1362 miles are city and county road s, 6312 miles are canal roads, and 139 miles are federal roads

(BLM and USFS). 25.5% of entrained emissions and 5% of windblown emissions are estimated to

come from city and county roads over 50 ADT, whic h total 217 miles. Canal roads in total are

estimated to contribute 67% of the windblown emissi ons and 53% of the entrained emissions. It is

assumed that 0.5% of canal roads (31.5 miles) have 20 ADT or greater, and w ould thus be subject to

PR 805. For the purposes of this analysis, no re ductions are credited to federal roads, although

there will be reductions based on the BLM dust cont rol plan (PAR 800). To tal applicability for

non-farm roads is thus 5% for windblown and 26% for entrained dust, resulting in an overall

applicability percentage of 20%. (See also “Determination of PR 805 Applicability” spreadsheet in

Appendix B.) The composite control factor (ent rained and windblown) is estimated to be 60% 29



# , assuming that both the County and IID will choose gravelling to meet the requirements of PR 805.

(Emission reductions will increase if paving is ch osen as the control op tion, but budget analysis

indicates that paving an appreciabl e number of miles is not fiscally feasible.) Overall reductions

from PR 805 are estimated at 10.09 tons/day.

Imperial County Public Works Department has provided the following cost information for the

paving or gravelling of high ADT roads 30 

# . They estimate that it would cost $2,980 to apply dust

suppressant to 1 mile of unpaved road, $8,950 to gravel, grade, compact and water 1 mile of

unpaved road, and $131,200 to pave 1 mile of unpaved ro ad. It is the County’ s current intention to

comply with PR 805 by gravelling 10 % of the applicable roads per ye ar (~22 miles per year). The

annual cost of complying with PR 805 is thus approximately $194,000 per year. (Paving those

same roads would cost approximately $2,850,000.) Th e Imperial County Public Works Department

has also provided additional budget information. 31 

# The Department has budgeted $316,000 for

gravelling projects in FY2005-06.; this is based on a 1997 FEMA project that entailed four road

improvement (e.g. graveling) contracts for 550 m iles of unpaved roads at a cost of $9.5 million.

The current budget for paved road maintenance is $2 million per year. In addition, the Department

has purchased six traffic count ers at a cost of $1,240, to cond uct additional traffic counts on

unpaved roads in the county.

PR 806: Conservation Management Practices

PR 806 requires CMPs at all farms over 40 acres, which includes over 90% of farm acreage in

Imperial County. Thus, the appli cability is 90%. San Joaquin Va lley estimated emission reductions

from Rule 4550, which is functionally equivale nt to PR 806, by CMP and crop category. In

addition to assuming an 80% rule compliance fact or, information used to calculate the emission

reductions included an estimate of which CMP opti ons would be used for each crop type and CMP

28 

# Both from Final BACM Technological and Economic Feasibility Analysis, SJVAPCD 2003 PM 10 

# SIP, April 2003.

29 

# Based on control efficiency cited in San Joaquin Valley’s Final Draft Staff Report for Regulation VIII (May 2004).

30 

# Imperial County Public Works cost estimate of compliance, August 1, 2005.

31 

# Imperial County Public Works Department letter to ICAPCD, dated August 22, 2005.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -43- 

# category. That information is not available for Im perial County at this time. For purposes of

estimating emission reductions for this report, it is assumed that a composite control factor derived

from dividing Rule 4550 emission reductions by emi ssions for each source category can be applied

to Imperial County. (The Rule 4550 staff analys is assumed that the ru le applied 91% of San

Joaquin Valley farms, compared to 90% of Im perial County farms subject to PR 805. That

difference was accounted for in de termining PR 806 emission reductions .) Overall reductions from

PR 806 are estimated at 4.16 tons/day.

Costs for CMPs related to unpaved roads and tra ffic areas would be similar to control costs

presented for PR 803 (track-out controls) and PR 805 (unpaved road / traffic area controls). Costs

for CMPs for land preparation / cultivation and harvesting are hi ghly dependent on crop type and

the specific CMP option chosen. SJVAPCD 32 

# cites cost information was received from the

University of California Coopera tive Extension, UC Davis and ARB (various documents), Draft

Regulation VIII Staff Report dated September 2001, the 2003 PM10 Plan, inputs from UC Davis

Cooperative Extension, inputs from stakeholders , and NRCS/RCD, and internet research.

SJVAPCD determined 33 

# that for San Joaquin Valley farmers th at “(t)he cost effectiveness analysis

demonstrates a savings when reducing the num ber of passes for the Land Preparation CMP

Category. It also shows some potential savings in the Harvest CMP Category. For the other CMP

categories, the analysis gene rally shows a net cost.”

Cost-Effectiveness

The cost-effectiveness of the measures in each Regulation VIII rule is pr esented in Tables 5-2

though 5-7. These estimates of cost-effectiveness fo r the individual control measures in Regulation

VIII are based on the 2004 CARB staff report 34 

# for SB 656 and the 2003 San Joaquin Valley PM 10



# SIP 35 

# . Actual cost-effectiven ess estimates for controls in Imperi al County are expected to be the

same or less cost-effective than those listed in th e tables. Based on the rural nature of Imperial

County, it would be expected that the emission reductions associated with these measures will be

the same or smaller than those assumed in San Joaquin Valley and other areas. For example,

activity levels associated with emissions (e.g., VMT for paved roads, ADVT for unpaved roads)

will be lower in Imperial County than other areas, resulting in less emissions (and emission

reductions) for these sources. Cont rol costs in Imperial County may also be higher in some cases.

More current information is available for Ru le 805 implementation on county roads. Based on

information from Imperial County’s Public Works Department, 36 

# assuming that 10% of the

217miles of applicable high ADT roads are treated per year for ten years, and a 4% interest rate, the

cost-effectiveness of PR 805 for c ounty roads is approximately $795/t on. (The cost-effectiveness of

paving would be approximately $7,100/ton, but the ab solute cost ($2,850,000) is greater than the

entire paved and unpaved road maintenance budget for Imperial County). These estimates are

comparable to estimates in the SB 656 st aff report ($344/ton to $12,300/ton for stabilizing,

32 

# Final BACM Technological and Economic Feasibility Analysis, SJVAPCD 2003 PM 10 

# SIP, April 2003 and Appendix

B, Rule 4550 Final Staff Report, SJVAPCD, April 15, 2004.

33 

# Appendix B, Rule 4550 Final Staff Report, SJVAPCD, April 15, 2004.

34 

# CARB Staff Report, Proposed List of Measures to Reduce Particulate Matter – PM10and PM2.5 (Implementation of

Senate Bill 656, Sher 2003), October 18, 2004.

35 

# SJVAPCD 2003 PM 10 

# SIP, Appendix G, BACM/T and RACM/T Demonstration for Sources of PM 10 

# and PM 10 

# Precursors in the San Joaquin Valley Air Basin, SJVAPCD, April 2003.

36 

# Imperial County Public Works cost estimate of compliance, August 1, 2005.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L E N V I R O N -44- 

# gravelling and paving) 37 

# and in other non-attainment area BACM analyses ($2,100/ton to

$5,900/ton for paving in the San Joaquin Valley) 38



# .

Certain dust control measures, as identified in Senate Bill 656, are not included in proposed

Regulation VIII amendments based on technical reasons such as the source is not present (e.g.,

winter non-skid sand) or the c ontrol cannot be applied effectiv ely in Imperial County (e.g. PM 10 

# - certified sweepers). These measures are identifi ed in Table 5-8. No potential BACM measures

have been excluded based on cost-effectiveness, although a cost-effectivene ss analysis of PR 805

provisions for unpaved parking lots and othe r traffic areas is being conducted.

37 

# CARB Staff Report, Proposed List of Measures to Reduce Particulate Matter – PM10and PM2.5 (Implementation of

Senate Bill 656, Sher 2003), October 18, 2004.

38 

# Final BACM Technological and Economic Feasibility Analysis, SJVAPCD 2003 PM 10 

# SIP, April 2003.Technical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-45-Table 5-2. Cost-effectiveness of measures in Proposed Rule 801 – Construction and DemolitionNOTE: Construction and demolition source categories are below the DM level.PR 801SB 656Measure No.SB 656 ($/ton)SJVUAPCD ($/ton)E.1.a-b Limit VDE to 20% opacity for sites of > 1 acre 24-26.a Watering $301/ton See belowF1.a.Pre-Activity: Pre-water site and phase work toreduce amount of distributed surface areaF1.bDuring Active Operation: apply water orchemical stabilizer; or construct and maintain awind barrierF.1.b.3Apply water or chemical stabilizer to unpavedhaul/access roads and unpaved vehicle/equipmenttraffic areasF.1.cPeriods of Inactivity: restrict vehicular access;and apply water or chemicalstabilizer. If area >0.5 acres of disturbed surface area remains unusedfor 3 7 days, area must comply with conditions forstabilized surface area24-26.b,39, and 40RACM to BACM upgrade:$197/ton[NOTE: based on SCAQMDminor upgrades. Notappropriate comparison]Apply water and/or dustsuppressants at end of day:$7,222,000/tonProhibit Demolition activities whenwind>25 mph: $847,000/tonDust Monitoring:$231,000-$339,000/ton12% soil moisture for earthmoving:$21,600-$56,000/ton15 mph speed limit $850/tonposting of speed limit $2,940-$74,600/tonDust Control Plans:$17,2000-$31,500/tonRequire notification for earthmovingoperations $2,480-$14,800/tonTechnical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-46-Table 5-3. Cost-effectiveness of measures in Proposed Rule 802 – Bulk MaterialsNOTE: Bulk materials source categories are below the DM level.PR 802SB 656Measure No.SB 656 ($/ton)SJVUAPCD ($/ton)ELimit VDE to 20% opacity for bulk materialhandling, material transport, and haul trucks28.a$1,151/ton (handling) to$28,293/ton (storage)None ReportedF.1.a Spray with water priorF.1.b Apply and maintain chemical stabilizer28.b and 41a.RACM to BACM upgrade:$197/tonF.1.cProtect from wind erosion by sheltering orenclosing the operation and transfer line28.a See 28.a. aboveF.1.dCover bulk materials stored outdoors withtarps, plastic, or other material28.a See 28.a. aboveRequire Construction of 3-sidedenclosures with 50% porosity:$659,000/tonF.2.aCompletely cover or enclose all Haul Truckloads of Bulk Material28.a See 28.a. aboveF.2.b, c, dMaterial transport: cover, freeboard,housekeeping28.b See 28.b. aboveTechnical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-47-Table 5-4. Cost-effectiveness of measures in Proposed Rule 803 – Track-out and Carry-outNOTE: Track-out and carry-out sourcecategories are below the DM level.PR 803SB 656Measure No.SB 656 ($/ton)SJVUAPCD ($/ton)F.1.aRapidly clean up any bulk material tracked out orcarried out onto a paved road surface by the end ofthe day29-30Manual Sweeping: $3,54/tonControl devices installed ataccess points to public roads:$13,700 to $322,000/tonLength of paved interiorroads: $7,930 to$186,000/tonAll sites with access to a paved road and with > 150ADT, or > 20 ADT by vehicles with > 3 axles shall:F.1.bInstall one or more Track-Out Prevention Devices orwash down system at access points; orF.1.cApply and maintain paving, chemical stabilization, orgravel for a distance of 50 ormore consecutive feet ataccess points29.b <$100/tonImpose Rule 8041 Requirements:$44,100-$387,000/tonRequire track-out control devices tobe 25 ft long and road width:$13,700-$322,000/tonRequire paved interior roads to be100 ft long and full road width:$7,930-$186,000/tonGravel pads: $27,000-$322,000/tonTechnical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-48-Table 5-5. Cost-effectiveness of measures in Proposed Rule 804 – Open AreasNOTE: Open areas source categories are above the DM level.PR 804SB 656Measure No.SB 656 ($/ton)SJVUAPCD ($/ton)E.1 Limit open areas to VDE of 20% opacity 31.aWatering:$7020/tonE.2Prevent unauthorized vehicle access by posting "NoTrespassing" signs or installing physical barrierssuch as fences, gates, posts, and/or appropriatebarriers to prevent access31.aWatering:$7,020/tonNone ReportedF.1.aApply and maintain water or dust suppressant to allundefeated areasF.1.bEstablish vegetation on all previously disturbedareasF.1.cPave, apply and maintain gravel or apply andmaintain chemical stabilizers/suppressants27, 31, and 4227b. RACM to BACMupgrade: $197/ton31a. Watering: $7,020/ton31b. RACM to BACMupgrade: $197/ton42. $697/tonImpose Rule 8051 requirements onurban parcels of 0.5 acres or morethat have a least 1,000 square feet ofdisturbed surface: $67,800/tonImpose Rule 8051 requirementsimmediately after cessation ofdisturbance: $6,450-$33,600/tonTechnical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-49-Table 5-6. Cost-effectiveness of measures in Proposed Rule 805 – Paved and Unpaved RoadsNOTE: The unpaved roads source category is above the DM level.PR 805 – Unpaved RoadsSB 656Measure No.SB 656 ($/ton) SJVUAPCD ($/ton)F.1.a Pave orF.1.b Apply chemicalstabilizers orF.1.cApply and maintain gravel, recrushed/recycledasphalt or other material of low silt content to adepth of > 3 inches orF.1.d Apply water one or more time daily orF.1.F Permanent road closure orF.1.fAny other method to meet VDE of 20% opacityand meets conditions of a stabilized unpavedroad35-3635. Apply water, gravel,chemical or dust suppressant,or pave: $344 to $12,293/ton36a.-Apply water, dustsuppressant, gravel, pave:$56 to $1,481/ton-Paving: $2,160 to$5,920/ton36b. $958/tonLimit speed to 25 mph: $1,080/tonRequire roads in urban areas to bepaved: $2,160-$5,920/tonImpose Rule 8071: $3,510/tonF.2.athrough gCanal Roads measures None Not Estimated None ReportedUnpaved Traffic AreasF.3.a Pave orF.3.b Apply chemicalstabilizers orF.3.cApply and maintain gravel, recrushed/recycledasphalt or other material of low silt content to adepth of 3 3 inches orF.3.d Apply water one or more time daily35-36 See 35-36 above See 35-36 aboveTechnical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-50-Table 5-6. Cost-effectiveness of Measures in Proposed Rule 805 – Paved and Unpaved Roads (continued)NOTE: The paved road source category is below the DM level.PR 805 – New and Modified Paved RoadsSB 656Measure No.SB 656 ($/ton) SJVUAPCD ($/ton)F.4.1New or modified paved roads with projected ADT >500 vehicles shall construct paved shoulders of 4 ft(500-3000 vehicle trips) or 8ft (> 3000 vehicle trips)32F.4.2In lieu of F.4.1, a curbing adjacent to and contiguouswith the travel lane or paved shoulder or road may beconstructed32F.4.3In lieu of F.4.1, intersections, auxiliary entry lanesand auxiliary exit lanes may be constructed adjacentto and contiguous with the roadway32F.4.4Medians shall be constructed with paved shouldershaving a minimum width of 4 ft. adjacent to trafficlanes for projects ADT > 500, unless speed limit < 45mph with curbing or landscaped medians32F.6In lieu of paving or vegetation requirement, mayapply oils or otherchemical stabilizers3232a. 4 ft. Paved shoulder on50% of highest ADT existingpaved roads: $7,290-$11,300/ton32b. Curb and Gutter roadshoulder: $5577/ton4ft paved shoulders on allnew/modified paved roads: $13,800-$508,000/ton4ft paved shoulder on 50% highestADT existing paved roads: $7,290-$11,300/tonRequire wind-or water-bornedeposition to be cleaned up within24 hrs: $2,850/tonTechnical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-51-Table 5-7. Cost-effectiveness of measures in Proposed Rule 806 – Conservation Management PracticesNOTE: Some agricultural operationssource categories (eg. tilling and windblown) are above the DM level.PR 806SB 656Measure No.SB 656 ($/ton) SJVUAPCD ($/ton)D.1Shall implement at least one of the followingpractices if own/operate acommercial farm of > 40acres: land preparation and cultivation; harvestactivities; unpaved roads;or unpaved equipmentoperation yards.D.4Prepare and submit a CMP application for eachagricultural operation site43.bHighwind tilling prohibitionand stabilization of fallowfields: $134/tonE.1 Land Preparation and Cultivation 43.c $8/tonE.2 Harvesting 43.b None providedE.3 Unpaved Farm Roads 43.a and d $958/tonE.4 Equipment Traffic Areas 43.d $958/tonOverall:$8 to $2,500/tonTechnical Memorandum: Regulation VIII BACM AnalysisOctober 2005D R A F T F I N A LE N V I R O N-52-Table 5-8 Senate Bill 656 Measures Not in the Proposed Regulation VIII Amended RulesSB656 Cost-EffectivenessComment33Requires use of certified PM10efficient street$1,119/ton (1996$)A Rule 1186-certifiedsweeper is $37,000 moreexpensive than aconventional sweeper.As noted in the SJVUAPCD “BACM/BACT and RACM/RACTDemonstration for Sources of PM10and PM10Precursors in the SanJoaquin Valley Air Basin,” (dated April 28, 2003), “use of these unitswill result in safety problems on freeways and rural roads in flat terrain.”The overwhelming majority of roads in Imperial County are freewaysand rural roads in flat terrain. For maximum efficiency, sweepers musttravel less than 5 mph.34Requires vacuum-street sweeping onroads to remove sand and cinders thatare placed on the road during winterstorms as an anti-skid material. .$350/ton (1996$)(assumes 2,400 lb/daywinter-day emissionreductions)This Great Basin Unified APCD measure does not apply to ImperialCounty, where anti-skid material is not used.37a.and37b.Weed Abatement ActivitiesPre-activity Requirements: 1) Prewatering to limit VDE opacity to20%; or 2) phasing work to reduceamount of disturbed surface area.Apply water during active operationsto limit VDE to 20% opacity.Apply water or chemical stabilizers tomeet conditions of stabilized surface.Not estimated Emissions from this source arenot quantified and considered de minimis.38 Defines windblown dusts NA No specific requirements.41b.Additional bulk material controlrequirements for Coachella Valleysource$352 - $462 /ton (1992 $)Controls specific to Coachella Valley blowsand zone, which does notexist in Imperial County.

# Technical Memorandum: Regulation VIII BACM Analysis October 2005

D R A F T F I N A L -58- E N V I R O N 

# 6. CONCLUSIONS

This report presents the BACM determination ba sed on proposed Regulation VIII amendments.

It includes all elements of a BACM determinatio n, including inventory assessment, calculation

of the de minimis emission level, identification of significant sources (e .g. those sources which

emit more than the DM level), a comparative anal ysis of proposed Regulation VIII amendments

for significant sources with re gulations adopted by serious PM 10 

# non-attainment areas, and a

presentation of cost-effectiveness of the dust control measures. The proposed Regulation VIII

BACM amendments are based on BACM recentl y adopted by other serious non-attainment

areas. This technical memorandum presen ted the existing inventory of primary PM 10 

# sources

and determined the de minimis level of primary PM 10 

# for Imperial County, based on that

inventory and recent ambient PM 10 

# levels. Based on the calculated DM level of 4.9 tons/day of

PM 10 

# , significant sour ces of primary PM 10 

# in Imperial County were identified. Those sources are

unpaved road and surface dust, disturbed open ar eas, and certain agricu ltural sources. A

comparative analysis of the proposed Regulati on VIII amendments and other BACM rules in

serious PM 10 

# non-attainment areas was presented. This comparative analysis was done for both

significant sources and sources belo w the DM level. For significant sources, a discussion of the

stringency of threshold limits and requirements co mpared to the most stringent in other serious

non-attainment areas was presente d, including justifica tion of less stringent thresholds and/or

requirements, if necessary. Emission reductions a nd costs associated with each proposed rule

were presented. Except for unpaved parking lots and staging areas, proposed Regulation VIII

thresholds and requirements were demonstrated to be as stringen t as the most stringent adopted

in other serious PM 10 

# non-attainment areas. Further cost-effectiveness analysis will be

conducted for unpaved parking lots and stag ing areas. Imperial County will propose

amendments to PR 805 reflecting more stringent th reshold and requirements if they are shown to

be cost –effective. Emission reduction, cost info rmation, and cost-effectiveness estimates for the

proposed Regulation VIII rules and/or control measures in the proposed Regulation VIII rules

were presented. Cost-effectiveness estimates fo r control measures not included in Regulation

VIII were also presented. No potential BACM measures were excluded based on costeffectiveness. Except for unpaved traffic areas (f or which the cost-effectiveness justification of

thresholds and requirements has not been comp leted), Proposed Regulation VIII amendments for

sources above the DM level have been determin ed to be BACM for Imperial County, based on

comparative analysis with fugitive dust rules in serious non-attainment areas. Measures

excluded from proposed Regulation VIII have be en excluded for technical or implementation

reasons, not cost-effectiveness.