4-25 4.4.2 Public Workshops

Beginning in September 1999, CCDCP and AQD staff jointly conducted a series of workshops to develop new fugitive dust controls for disturbed open areas and vacant lots. Initially, these regulations were developed

as amendments to the existi ng Section 41 Air Quality Regulations. As draft r egulations were developed for other fugitive dust sources, they were also incorporated

into Section 41. As a resu lt of public comments made during the workshop process, regulations for the control of disturbed open areas and weed abatement; unpaved roads; unpaved parking lots; and construction activities were separated into individual sections of the Air Quality Regulations in May of 2000. The draft regulations for disturbed open areas were rewritten as a new Section 90. Draft regulations for unpaved roads were rewritten

as Section 91. Draft r egulations for unpaved parking lots were rewritten as Section 92. Draft regulations for street sweeping equipment, paved road shoulders, and paved medians were developed as Section 93. Draft regulations for enhanced requi rements for construction activities became Section 94. A total of 20 workshops were conducted between September 1999 and

November 2000 on these draft regulations.

Documentation for the works hops is in Appendix F. These workshops were advertised and opened to the public in compliance with NRS 241 Open Meeting Law requirements.

In the following sections (4 .4.2.1 through 4.4.2.5) a summary of the significant issues brought up at the workshops is provided for each of the major topics/significant emission sour ces that were addressed. A chart is provided for each significant source category that lists the potential BACM from Section 4.3 and

indicates the decision result ing from the evaluation of

each measure to either develop/strengthen appropriate

control measures or to discount the measure from

further consideration. A discussion of the implemented

control measures is then provided in Section 4.5.

4.4.2.1 Emission Inventory Issues During these workshops, concern was expressed regarding the draft emission inventories prepared by the CCDCP. Almost all participants believed that the Workshops Held on Fugitive Dust Controls

Emission Inventories

Discussed4-26 emissions from paved roads were greatly

overestimated. The CCDCP st aff explained the U. S. EPA approved AP-42 emission al gorithm for paved road dust, noted that research on paved road dust emissions was ongoing, and committed to updating the inventories

when better emission estimates were available. There was some disagreement am ong stakeholders over the contribution of unpaved road dus t to the inventories. Many felt that this source category might be

underestimated in the inventor y. Some members of the public also indicated that t hey thought the estimates of emissions from disturbed open areas were

overestimated. There was much discussion on the contribution of construction activities, including the contribution of silt loadings on paved roads from construction activities. CCDCP explained how the emission inventory estimates were developed and has

refined the draft emission inventories. The inventories are discussed in Chapter 3 and Appendix B of this SIP.

4.4.2.2 Disturbed Open Area/Vacant Lot/Unpaved Parking Lot Issues

Listed below in Table 4- 10 are the BACM implemented for emissions from disturbed vacant land and unpaved parking lots identified as a result of the research performed as described above. For a detailed description of the implement ed control measures, see Sections 4.5.2.1, 4.5.2. 2, 4.5.3.1 and 4.5.3.2. Emission Inventory Development

Discussed in Appendix B

Table 4-10

BACM for Disturbed Vacant Land and Unpaved Parking Lots

Control Measure Implemented Limit off-road use of RVs on open land Yes

Vacant land stabilization Yes Construct windbreaks Optional

Controls on weed abatement Yes Prohibit unpaved parking lots Proposed Stabilize surface of unpaved parking lots Yes Dust abatement and management plans for large tracts of gover nmentally owned lands Partial – See discussion below4-27 Major issues related to the potential control measures for disturbed open areas and vacant lots included 1) the cost to property owners of complying with the proposed requirements, and 2) the liabi lity of property owners to pay the cost of remediating unauthorized dumping and ATV use on their property. Another concern was that local regulations sometime s make it difficult or impossible to get local approval to fence a parcel. Some participants expressed the opinion that it was acceptable to require stabiliz ation and prevent vehicular use on urban vacant lots, but that the regulations should not apply to “open areas.” They expressed the view that the County should not adopt regulations that would result in “fencing off the desert.”

The use of windbreaks was addressed and they were determined to be suitable as an optional control measure. This option was made subject to approval since requirements that were developed and included in AQR Section 90 to prevent motor vehicle trespass and

to stabilize disturbed surfaces are more stringent than a stand alone requirement to construct windbreaks. The placement of windbreaks in terms of both orientation and spacing is critical if windbr eaks are to be effective in controlling dust. Where su rfaces have been stabilized, windbreaks are not necessary. Therefore, AQR Section 90 does not require that windbreaks be constructed, but leaves this control as an option if approved by the AQD Control Officer and U. S. EPA. Approval is subject to a

determination that use of windbreaks as proposed will provide a level of contro l equivalent to other BACM approved for open areas and disturbed vacant land.

Site-specific dust mitigation plans for large parcels were discussed by CCDCP and AQD staff. As discussed in Section 4.3.1, requiring dust mitigation plans for individual parcels was not found to be cost effective. However, stabilization plans from large property owners with several parcels would be an effective method for enforcing vacant land regulations. This would be especially effective if the parcels had a high potential of being disturbed. As described in Section 4.8.3.3, Clark County is proposing an amendment to AQR Section 90.2.1.3 to require proper ty owners managing over 10,000 acres to prepare dust mitigation plans by January 1, 2002. It was dec ided that requiring plans Disturbed Open Areas

Issues Discussed4-28 would be an enforcement burden, but that large property owners, including government al entities, would be contacted individually and plans developed for their parcels.

The proposed U. S. EPA test methods for soil surface stability, which were used in the Maricopa County Federal Implementation Plan (FIP), were extensively
criticized. AQD enforcement staff suggested thatthese

tests were too labor intensive to allow for cost-effective

enforcement of the regulation. Mem bers of the public said the tests were too complicated for the average property owner to be able to use in determining if his/her property was in compliance with the regulatio n. At the end of these discussions, a general consensus evolved that resulted in the adoption of Secti on 90 of the Air Quality Regulations.

Some of the comments made concerning the requirements for disturbed open areas were also made concerning the proposals to r egulate vacant lots. These included comments on cost, te st methods, and fencing. Use of unpaved areas for intermittent parking was also discussed at length. At t he end of these discussions, a general consensus evolved t hat resulted in the adoption
of Section 92 of the Air Q uality Regulations, requiring vacant lots and disturbed open areas to be stabilized and off-road vehicle use prohibited.

Current zoning regulations and development standards for Clark County and the cities of Las Vegas, North Las Vegas, and Henderson generally require paved parking for new development. Consideration was therefore given to prohibiting construction of any new unpaved parking lots. During consideration of this issue, it was noted that requiring paved par king lots for rural public facilities such as trailheads, campgrounds, etc., might

conflict with the rural natur e of these facilities and require more intensive construction in these rural areas. A consensus evolved to allow stabilization of unpaved parking lots in lieu of a m andatory paving requirement.For urban parking facilities that are used on a yearround basis, it is believed t hat paving will be the most cost-effective stabilization method. Clark County currently proposes to strengt hen this requirement by Soil Surface Stability

Tests Difficult To Use

Vacant Lots, Disturbed Open Areas To Be Stabilized; Off-Road

Vehicle Use Prohibited4-29 prohibiting construction of new unpaved parking lots except where a paved parking lot conflicts with rural facilities such as trailheads or campgrounds.

4.4.2.3 Construction Activity Issues

The BACM identified for control of dust from

construction activities are listed in Table 4-11. A detailed description of the implemented control

measures can be found in Sect ions 4.5.2.3 and 4.5.3.3.

Table 4-11

BACM for Construction Activities

Control Measure Implemented

Strengthen requirements of existing fugitive dust control rules Yes

Provide for better enforcement of fugitive dust control rules Yes Mitigation bond requirement to insure implementation of dust control plan Yes

Dust control plans for construction/land clearing and

demolition Yes

Dust control monitor required for construction sites having more than 50 acres of actively disturbed area Yes

Track out control Yes Staging areas, equipment st orage, and material storage

areas Yes

Use of surfactants or tackifiers Yes High-wind operating restrictions Yes Phasing land development Yes -- Partial

Stabilized disturbed inactive surfaces Yes Dust controls for blasting of soil and rock Yes Dust controls for abrasive blasting Yes Dust controls for crushing Yes Dust controls for landscaping Yes Dust controls for paving/subgrade preparation Yes Dust controls for screening Yes

Dust controls for construction traffic Yes Dust controls for trenching Yes Dust controls for truck loading Yes Dust controls for stockpiles Yes Require visible emission limits not to exceed 20% opacity Yes

Limit visible emissions to 100 feet Yes

Prevent visible emissions from crossing property line Proposed4-30 For several construction activities, Clark County did not find specific control measur es adopted in other areas through the potential BACM research. New control measures were developed by Clark County as potential

BACM to reduce emissions from these construction

activities.

Extensive discussion was hel d on developing new and

enhanced control measures for construction activities.

Stakeholders noted that our minimum fines are the highest in the nation for fugiti ve dust violations, but that we still are violating the feder al air quality standards. It

was asserted that the “c ommand and control” approach had not proven effective here. Examples were cited where permit conditions under the current rule did not

allow the most efficient or co st-effective control measure to be employed. The need to be able to apply the most appropriate Best Management Pr actice for the job was emphasized. A suggestion was made to issue only one dust control permit for each project and make the applicant responsible for dust control on the project.

Concerns were expressed regarding the U. S. EPA opacity test. Some participant s expressed doubt that it would be possible to comply with this standard when working in difficult soils. CCDCP staff noted that U. S. EPA required a quantitative, verifiable, and repeatable

test method that could be related to the reduced

emissions that would o ccur from the effective application of control meas ures. There was agreement to continue development of better test methods beyond

submittal of the SIP.

The Particulate Matter Control Research Advisory Committee (Advisory Committ ee) has funded a study of

test methods that can be used to enforce the dust

control standards for construction activities. U. S. EPA has provided additional funding for the study. The study began in early 2001, and it is expected the study will be finalized by August of the same year. The CCDCP has made a SIP commitment to initiate an additional study if the results of this study do not produce test methods that are acceptable. It is anticipated that the current study will result in acceptable test methods. The difficulty in developing acc eptable test methods lies in the variety of activities t hat take place on construction Construction Activities

Control Measures

Study Funded To Develop Test Methods4-31 sites and the different soil types present in the Las Vegas Valley.

After extensive discussion, it was generally agreed that the new regulatory program s hould require site-specific and phase-specific dust control permits for larger projects and that the regulat ion incorporate an extensive list of BMP that would prov ide a comprehensive set of BACM to address fugitive dust from construction sites. BMP should generally be selected based on soil type as well as other factors specific to the construction site and activity. One suggestion put forward but not adopted

was a limitation on the ac reage that could be graded and disturbed at any one ti me. Opponents of this proposal suggested that in some instances, on very large projects, this requirement could force off-site hauling and stockpiling of fill dirt. This would not be necessary if there was not a limitation on the acreage that could be graded and k ept disturbed at any one

time. Staff reviewed dust control permits for large projects and determined that these issues were valid. It was also argued that the requirements for stabilizing any areas of a construction site that were disturbed would force developers to minimize disturbed areas to

the maximum extent feasib le for economic reasons.

During the workshop process, it was noted that Maricopa County required dust control permits for all construction sites of one-tenth (0.1) acre or larger, whereas Clark County requires dust control permits for construction sites of one-quarte r (0.25) acre or larger, trenching operations of 100 feet or greater, or demolition of structures of 1,000 square f eet or greater. In some instances, the latter permit thresholds for dust producing activities may mandate permits on parcels of less than

0.1 acre. Consideration wa s given to reducing the construction site size threshold to one-tenth (0.1) acre for requiring dust control permits. Most construction activities on these very small sites that do not include trenching or demolition are limited to remodeling. Small-scale remodeling does not typically involve significant dust producing acti vities. In addition, the Clark County regulation requi res that BMP be employed for any dust producing activity that occurs, even when a permit is not required. It was therefore determined that reducing the construction site size threshold for Site-Specific Dust Mitigation Plans Part

of BMP

Reducing

Construction Site Size

Threshold Provides No Air Quality Benefit4-32 requiring dust control permi ts would provide no air quality benefits.

Only one potential control measure for construction activities was rejected as infeasible for BACM during the rule development process. Prevention of visible emissions from crossing proper ty lines was discussed at length during the rule development process. This performance standard was determined to be both infeasible and ineffective. For public works agencies and contractors working on r oad construction projects, this requirement may result in a no-visible-emissions standard due to the close proximity of a property line next to road rights-of-way. The same concern applies to any other work that occurs next to a property line. It would not be possible to comp ly with the required level

of control that this performance standard would

mandate under these circumstances.

On the other hand, for construction work that occurs on a large section of land, this performance standard may

allow almost unlimited em issions. Under these circumstances, this performance standard would provide no air quality benef its. This performance standard was therefore reje cted as a BACM measure

for construction activities.

As a result of public comm ents received during the SIP development process, Clark County has reassessed this issue and determined that under some circumstances, this may be an appropriate performance standard. Therefore, Clark County is proposing to amend Section
9.4 of the AQR to incor porate this requirement.

At the end of these discu ssions, a general consensus evolved that resulted in the adoption of Section 94 of the Air Quality Regulations and the Section 94 Handbook of Best Management Practices by the Clark County Health

District Board of Health. Visible Emissions Crossing Property

Lines Deemed Infeasible, Ineffective

Section 94 Adopted4-33 4.4.2.4 Paved Road Issues

Table 4-12 identifies the potential BACM that were identified for control of pav ed road dust. For a detailed description of the implement ed control measures, see

Sections 4.5.2.4 and 4.5.3.4.

Table 4-12

BACM for Paved Road Dust

Control Measure Implemented

Preventing deposition of mate rial onto paved roadways – stabilizing unpaved access points Yes

Preventing deposition of mate rial onto paved roads –

construction track out Yes

Preventing deposition of mate rial onto paved roads –

industrial site track out Yes

Use of Pm 10 -efficient sweepers to clean paved roads Yes

Use of vacuum crack seal equipment Yes Preventing deposition of mate rial onto paved roads – stabilizing shoulders on paved roads Yes

Preventing deposition of mate rial onto paved roads – material transport controls –truck covers, freeboard requirement Yes

Preventing deposition of materi al onto roads – storm water drainage Yes

Cleanup of material spills and erosion-caused deposits Yes Routine sweeping/cleaning of paved roads Yes

Some public works agencies initially expressed concern that the proposed draft regulat ions would require all new street sweeping equipment to be certified PM-efficient.

This concern related to the need to retain some broomtype sweepers in the fleet. This issue was resolved

when it was determined that t he current list of Certified PM-Efficient Sweepers include d broom sweepers. It was also suggested that the regulations allow the use of sweeping equipment that is “equivalent” to certified equipment. The issue of requiring new sweeping equipment for sweeping parking lots to be certified All Street Cleaning Equipment To Be

Certified PM-Efficient4-34 PM-efficient was discussed at some length. At the end of these discussions, a general consensus evolved that resulted in the adoption of t he sweeping requirements in
Section 93 of the Air Qualit y Regulations, which require all street cleaning equipm ent to be certified.

All of the public works departments have established programs for sweeping frequency in order to maximize

the emission reduction benef its from their sweeper resources. These program s are described in Appendix

J.

The value of requiring paved road unpaved shoulders

and medians to be stabilized and the time frame in

which this should occur was discussed. Related to this discussion was the desire to pres erve horse trails in the road rights-of-way in certain rural areas. Public works agencies indicated that surveying rights-of-way and establishing drainage wher e these improvements are required will take time and be expensive to resolve in

some situations. The costs that could incur for the maintenance of limited access freeway rights-of-way and the difficulty of maintaining these areas were issues raised by the Nevada Department of Transportation (NDOT). At the end of these discussions, a general consensus evolved that resulted in the adoption of paved road unpaved shoulder and median stabilization requirements in Section 93 of the Air Quality Regulations, requiring unst able shoulders and medians to be stabilized within 365 days of discovery. Public works departments are devel oping plans for shoulder

stabilization as described in Section 4.5.2.4.3.

Control measures to c ontrol track out from stationary/industrial sources are addressed in Section 4.6.1.1. Stationary sour ces are classified as an insignificant source category, but control measures to reduce track out onto paved r oads are incorporated in the permit conditions for each source.

Vacuum-type crack seal equipment evaluated by Public Works departments in the valley have been found to be of poor design and did not work well. Evaluation of offthe-shelf equipment availa ble from manufacturers concluded that the current technology needs modification and/or improv ement before t he equipment Paved Road Unpaved

Shoulder and Median

Stabilization Requirements Adopted

Vacuum-Type Crack Seal Equipment Must

Be Purchased in the

Future4-35 Is as an effective means of reducing emissions in the crack sealing process. However, these modifications have been found to be relatively minor and Clark County is proposing to amend AQR Se ction 93 to require that future purchases of crack seal equipment employ this technology.

4.4.2.5 Unpaved Road Issues The BACM implemented for unpav ed roads are listed in the controls shown in Table 4-13. A detailed description

of these control measures is provided in Sections

4.5.2.5 and 4.5.3.5.

Table 4-13

BACM for Unpaved Roads

Control Measure Implemented

Surface treatment to reduce dust from unpaved roads and alleys Yes

Prohibition on new unpaved roads in public thoroughfares Yes

Traffic reduction/speed control for unpaved roads Yes - For Construction

Roads

Potential control measures for unpaved roads were extensively discussed, with some participants suggesting that all unpaved roads should be paved and others suggesting that a much higher threshold for vehicle trips should be used for triggering a paving requirement. The time tabl e for bringing unpaved roads into compliance was also discussed at length.

After extended discussion spanning a number of workshops, a consensus was reached to require paving of all unpaved roads with vehicle traffic of 150 trips per day or greater over a three- year period, with one third of the roads paved each year. T he only source from which the level of funding for paving roads can be acquired is through the Congestion Mitigation and Air Quality Improvement program (CMAQ) . However, the total funding needed to ensure pavin g of these roads can only be accrued over a thr ee-year period. The infeasibility of obtaining t he funding necessary for this paving program in a shorter time period is a fa ctor that Unpaved Roads

Control Measures

CMAQ Funding

Commitment To Pave Unpaved Roads4-36 prevents Clark County from dem onstrating attainment of

the 24-hour standard before 2006.

Extended discussions took place on what constituted an unpaved road, who should be res ponsible in the case of easements, and who should be responsible for roads in public rights-of-way where a public agency has not accepted the road. A majori ty of participants indicated that they thought that the regulations should be drafted to allow the road-paving offset credits program to

continue. At the end of these discussions, a general consensus evolved that resulted in the adoption of
Section 91 of the Air Qua lity Regulations, requiring unpaved roads with greater than 150 ADT to be

stabilized.

Toward the end of these workshops, the issue of property owner and developer liability for potential environmental damage fr om the use of dust suppressant products emerged. As a result of these discussions, Clark County has committed to working

with the State of Nevada to facilitate development and adoption of specifications for dust suppressant product

use in Nevada.

4.4.3 Public Hearings and Adoption

After public notice in compliance with NRS 241, a 30-day public comment period was scheduled and public hearing set for Ma rch 23, 2000 on amendments to Section 41 for consideration by the Clark County Board of Health. This hearing was continued to the April 27, 2000 meeting of the Clark County Board of Health. After rewriting the draft regulations as

amendments to Section 0 and adding Sections 90, 91, 92, 93, and 94, a public hearing was scheduled for the May 25, 2000 meeting of t he Clark County Board of Health. This hearing was continued to the June 22, 2000 Board of Health meeting. The draft Sections 93 and 94 were also scheduled for a hearing at the June 22, 2000 Board of Health m eeting. On June 22, 2000, the Clark County Board of Health amended Section 0 and adopted Sections 90, 91, 92, 93, and 94. On July 27, 2000, the Section 94 Handbook was scheduled for a public hearing by the Clark County Health District Board of Health on August 24, 2000. The Section 94 Funding Constraints

Prevent Attainment of

the 24-Hour Standard

Before 2006

Unpaved Roads Stabilization Adopted

Dust Suppressant Specifications

AQR Section 0 Amended; Sections 90, 91, 92, 93 and 94 Adopted in 20004-37 Handbook was subsequently ad opted at this meeting. The Clark County Health District Board of Health commenced a public comment period for Revised Sections 0 and 93 on September 28, 2000 and set a public hearing for November 16, 2000. The revised

draft Sections 0 and 93 were adopted at the November 16, 2000 meeting of the Clark County Health District

Board of Health. Document ation of the public hearing and adoption process is in Appendix F.

4.5 IMPLEMENTED CONTROL MEASURES

4.5.1 Control Measure Terminology

The terms emission reduction

, rule penetration

, rule

effectiveness , and overall (rule) reduction are used throughout this overview of Clark County control

measures. Emission reduc tion denotes the actual

reduction that can be achieved when the control measure is properly applied to a specific activity or source. An example of emission reduction would be the percent reductions achieved when paving an unpaved

road. The emission reduction is calculated by dividing

the emissions that occur a fter the control measure is applied by the emissions that occur before the control measure is applied.

Rule penetration is the per centage of a total source category that a particular ru le will impact. Continuing with the road example, if the rule applies to roads having more than 150 vehicle trips per day, then the rule penetration would be the emissions generated by roads having more than 150 vehicle trips per day as a percentage of the emissions from all of the unpaved

roads.

The term “rule effectiveness” is somewhat misleading.

Rule effectiveness is used to denote the rate of compliance with a rule. If, for example, operators of 80 percent of a source category that is subject to a control measure requirement implement the control measure, and comply at all times with its requirements, then this “rule effectiveness” is said to be 80 percent.

The overall reduction for a rule is calculated by multiplying the emission r eduction by the rule Control Measure

Terms Defined

Rule Penetration

Rule Effectiveness

Default of 80 Percent4-38 penetration and multiplying t he result by the rule effectiveness. This gives the overall emission reduction that is achieved by implementing the rule.

4.5.2 Adopted Control Measures for the 24-Hour
NAAQS

Table 4-14 provides a deta iled list of the specific

elements of the Clark Count y control measures adopted or implemented to achieve attainment of the 24-hour

PM 10 NAAQS.

Table 4-14

Significant PM 10 Sources Control Measures 24-Hour Standard

Source Category BACM-Control Measures Overall

Reduction Percentage

with

Control

Measures

Area Sources

Disturbed

Vacant Land • Prevent Motor Vehicle Access and Stabilize Disturbed Surface. {Section 90.2.1.1(a)}

• Stabilize Disturbed Surface greater than 5,000 sq.ft. with

Gravel or Dust Palliatives {Section 90.2.1.1(b)}

• Discing or Blading areas of 5,000 square feet or larger for

weed abatement, apply water both before and during operations {Section 90.2.2.1(a),(b)}

• After Discing or Blading occurs, stabilize disturbed surfaces

with Gravel, Water, Dust Palliatives, or Paving {Section 90.2.2.1(c)} 36% (2001)

72% (2002+)

Unpaved Parking Lots • Pave {Section 92.2.1.2(a)}

• Apply and Maintain Dust Palliatives {Section 92.2.1.2(b)}

• Apply and Maintain Dust Palliatives on Traffic Lanes and

apply surface gravel to depth of two inches on Parking Areas {Section 92.2.1.2(c)}

• (Proposed) Prohibition of new, unpaved parking lots

• (Proposed) Prohibition of dust crossing property line Wind Erosion 36% (2001) 72% (2002+)

Vehicles 24% (2001) 48% (2002+)

Construction Activity Fugitive Dust • Apply Dust Suppressant (water) throughout construction site to stabilize soil (Section 94 Handbook, CST 10-l)

• Apply Dust Palliative on soils based on soil type (Section 94

Handbook, CST 12)

• Traffic Control in Construction Area {Section 94 Handbook,

CST 10-2, CST 20-1, CST 19 Requirements & CST19-7)}

• Use tarps or other suitable enclosures on haul truck

(Section 94 Handbook, CST 13-1) 34 % (2001)

68 % (2003)4-39 Table 4-14

Significant PM 10 Sources Control Measures 24-Hour Standard (continued)

Source Category BACM-Control Measures Overall

Reduction Percentage

with

Control

Measures

Construction Activity Fugitive Dust

(continued) • Stabilize surface with materials that will prevent track out of mud and dirt to the Paved section, with wheel shakers, wheel washers {Section 94 Handbook, CST 19-3, 19-4 and Section 94.6.8.(c)}

• Permits Required for Construction Activities (Section 94.4.1)

• Public Information Signage Required (Section 94.4.5)

• Site-Specific Dust Mitigation Plan Required for Projects of ten

acres or greater in size (Section 94.4.9)

• Dust Control Monitor Required for Construction Activity

having 50 acres or more of actively Disturbed Soil (Section 94.4.11)

• 20% Opacity Limit on Dust Emissions {Section 94.5.2 &

94.6.8(d)}

• 100-yard Plume Limit {Section 94.6.8(b)}

• (Proposed) 100-foot plume limit

• (Proposed) Prohibition on dust crossing property line

• Controls Required on site at all times, whether or not

Construction Activity is occurring (Section 94.5.3)

• Backfilling (Section 94 Handbook, CST 1)

• Blasting – Abrasive (Section 94 Handbook, CST 2)

• Blasting – Soil and Rock (Section 94 Handbook, CST 3)

• Clearing and Grubbing (Section 94 Handbook, CST 4)

• Clearing Forms (Section 94 Handbook, CST 5)

• Crushing (Section 94 Handbook, CST 6)

• Cut and Fill (Section 94 Handbook, CST 7)

• Demolitions – Implosion (Section 94 Handbook, CST 8)

• Demolitions – Mechanical/Manual (Section 94 Handbook,

CST 9)

• Disturbed Land Large Tracts (Section 94 Handbook, CST 11)

• Dust Suppressant, Dust Palliative, and Surfactant Selection

and Use (Section 94 Handbook, CST 12)

• Landscaping (Section 94 Handbook, CST 14)

• Paving/Subgrade Preparation (Section 94 Handbook, CST

15)

• Screening (Section 94 Handbook, CST 16)

• Staging Areas (Section 94 Handbook, CST 17)

• Stockpiles (Section 94 Handbook, CST 18)

• Traffic – Construction Related (Section 94 Handbook, CST

20)

• Trenching (Section 94 Handbook, CST 21)4-40 Table 4-14

Significant PM 10 Sources Control Measures 24-Hour Standard (continued)

Source Category BACM-Control Measures Overall

Reduction Percentage

with Control

Measures

Construction Activity Fugitive Dust

(continued ) ♦ Truck Loading (Section 94 Handbook, CST 22)100-yard Plume Limit {Section 94.6.8(b)

♦ (Proposed) Prohibition on the use of dry rotary brushes or blower devices for cleanup of track out

Windblown

Construction

Dust • Apply Dust Suppressant (water) throughout construction site to stabilize soil (Section 94 Handbook, CST 10-l)

• Apply Dust Palliative on soils based on soil type (Section 94

Handbook, CST 12)

• Traffic Control in Construction Area (Section 94 Handbook,

CST 10-2, CST 20-1, CST 19 Requirements & CST19-7)

• Use tarps or other suitable enclosures on haul truck (Section

94 Handbook, CST 13-1)

• Stabilize surface with materials that will prevent track out of

mud and dirt to the Paved section, with wheel shakers, wheel washers {Section 94 Handbook, CST 19-3, 19-4 and Section 94.6.8.(c)}

• Permits Required for Construction Activities (Section 94.4.1)

• Public Information Signage Required (Section 94.4.5)

• Site-Specific Dust Mitigation Plan Required for Projects of

ten acres or greater in size (Section 94.4.9)

• Dust Control Monitor Required for Construction Activity

having 50 acres or more of actively Disturbed Soil (Section 94.4.11)

• 20% Opacity Limit on Dust Emissions {Section 94.5.2 &

94.6.8(d)}

• 100-yard Plume Limit {Section 94.6.8(b)}

• Controls Required on site at all times, whether or not

Construction Activity is occurring (Section 94.5.3)

• Backfilling (Section 94 Handbook, CST 1)

• Blasting – Abrasive (Section 94 Handbook, CST 2)

• Blasting – Soil and Rock (Section 94 Handbook, CST 3)

• Clearing and Grubbing (Section 94 Handbook, CST 4)

• Clearing Forms (Section 94 Handbook, CST 5)

• Crushing (Section 94 Handbook, CST 6)

• Cut and Fill (Section 94 Handbook, CST 7)

• Demolitions – Implosion (Section 94 Handbook, CST 8)

• Demolitions – Mechanical/Manual (Section 94 Handbook,

CST 9)

• Disturbed Land Large Tracts (Section 94 Handbook, CST

11)

• Dust Suppressant, Dust Palliative, and Surfactant Selection

and Use (Section 94 Handbook, CST 12) 36% (2001)

71% (2002+)4-41 Table 4-14

Significant PM 10 Sources Control Measures 24-Hour Standard (continued)

Source Category BACM-Control Measures Overall

Reduction Percentage

with

Control

Measures

Windblown

Construction

Dust (continued) • Landscaping (Section 94 Handbook, CST 14)

• Paving/Subgrade Preparation (Section 94 Handbook, CST

15)Screening (Section 94 Handbook, CST 16)

• Staging Areas (Section 94 Handbook, CST 17)

• Stockpiles (Section 94 Handbook, CST 18)

• Traffic – Construction Related (Section 94 Handbook, CST

20)

• Trenching (Section 94 Handbook, CST 21)

• Truck Loading (Section 94 Handbook, CST 22)

On-Road Mobile Sources

Paved Road Dust (includes

Construction

Track-Out) • Pave or Stabilize four feet of Shoulders (Section 93.2.1.1)

• (Proposed) Stabilize eight feet of shoulders on new roads

with 3,000 ADT or greater

• Pave or Stabilize Medians with solid paving across median

(Section 93.2.1.4)

• Use PM-Efficient Street Sweepers (Section 93.2.3.1)

• Establish routine frequent street sweeping programs

• Prevent haul truck track out and spillage (Section 94

Handbook, CSTs 13 & 22)

• Prevent mud and dirt track out with wheel shakers, or wheel

washers must be employed at Construction Sites to prevent mud and dirt track out onto paved roads (Section 94 Handbook, CST 19-3 & CST 19-4)

• Clean up mud and dirt track out at least once daily and when

track out extends more than 50 feet N/A 13

Unpaved

Road Dust • Pave Unpaved Roads With Traffic ≥ 150 ADT {Section 91.2.1.3(a)}; or

• Apply and Maintain Dust Palliatives to Unpaved Roads

With Traffic ≥ 150 ADT {Section 91.2.1.3(b)} Paving

Phase-In (2001) -22% (2002) -44% (2003+)-65%

13 No emission reductions taken for PM-Efficient Street Sweepers. Because there is not a linear relationship between silt loadin g and emission rates, the actual emission reductions will vary with the roadway mix in each inventory area.4-42 Table 4-14 Significant PM 10 Sources Control Measures 24-Hour Standard (continued)

Source Category

BACM-Control Measures Overall

Reduction Percentage

with

Control

Measures

Highway

Construction Project

Activities • Apply Dust Suppressant (water) throughout construction site to stabilize soil (Section 94 Handbook, CST 10-l)

• Apply Dust Palliative on soils based on soil type (Section 94

Handbook, CST 12)

• Traffic Control in Construction Area (Section 94 Handbook,

CST 10-2, Section 20-1, CST 19 Requirements & CST19-7)

• Use tarps or other suitable enclosures on haul truck (Section

94 Handbook, CST 13-1)

• Stabilize surface with materials that will prevent track out of

mud and dirt to the Paved section, with wheel shakers, wheel washers {Section 94 Handbook, CST 19-3, 19-4 and Section 94.6.8.(c)}

• Permits Required for Construction Activities (Section 94.4.1)

• Public Information Signage Required (Section 94.4.5)

• Site-Specific Dust Mitigation Plan Required for Projects of ten

acres or greater in size (Section 94.4.9)

• Dust Control Monitor Required for Construction Activity having

50 acres or more of actively Disturbed Soil (Section 94.4.11)

• 20% Opacity Limit on Dust Emissions {Section 94.5.2 &

94.6.8(d)}

• 100-yard Plume Limit {Section 94.6.8(b)}

• (Proposed) 100-foot plume limit

• (Proposed) Prohibition of dust crossing property line

• Controls Required on site at all times, whether or not

Construction Activity is occurring (Section 94.5.3)

• Backfilling (Section 94 Handbook, CST 1)

• Blasting – Abrasive (Section 94 Handbook, CST 2)

• Blasting – Soil and Rock (Section 94 Handbook, CST 3)

• Clearing and Grubbing (Section 94 Handbook, CST 4)

• Clearing Forms (Section 94 Handbook, CST 5)

• Crushing (Section 94 Handbook, CST 6)

• Cut and Fill (Section 94 Handbook, CST 7)

• Demolitions – Implosion (Section 94 Handbook, CST 8)

• Demolitions – Mechanical/Manual (Section 94 Handbook, CST

9)

• Disturbed Land Large Tracts (Section 94 Handbook, CST 11)

• Dust Suppressant, Dust Palliative, and Surfactant Selection

and Use (Section 94 Handbook, CST 12) 34% (2001)

68% (2003)4-43 Table 4-14

Significant PM 10 Sources Control Measures 24-Hour Standard (continued)

Source Category BACM-Control Measures Overall

Reduction Percentage

with

Control

Measures

Highway

Construction Project

Activities (continued) • Landscaping (Section 94 Handbook, CST 14)

• Paving/Subgrade Preparation (Section 94 Handbook, CST

15)

• (Proposed) Prohibition on use of dry rolling brushes or

blower devices for cleanup of track out

• (Proposed) Acquire only vacuum-type chip seal equipment

• Screening (Section 94 Handbook, CST 16)

• Staging Areas (Section 94 Handbook, CST 17)

• Stockpiles (Section 94 Handbook, CST 18)

• Traffic – Construction Related (Section 94 Handbook, CST

20)

• Trenching (Section 94 Handbook, CST 21)

• Truck Loading (Section 94 Handbook, CST 22)

Highway

Construction Project-Wind

Erosion • Apply Dust Suppressant (water) throughout construction site to stabilize soil (Section 94 Handbook, CST 10-l)

• Apply Dust Palliative on soils based on soil type (Section 94

Handbook, CST 12)

• Traffic Control in Construction Area (Section 94 Handbook,

CST 10-2, CST 20-1, CST 19 Requirements & CST19-7)

• Use tarps or other suitable enclosures on haul truck (Section

94 Handbook, CST 13-1)

• Stabilize surface with materials that will prevent track out of

mud and dirt to the Paved section, with wheel shakers, wheel washers {Section 94 Handbook, CST 19-3, 19-4 and Section 94.6.8.(c)}

• Permits Required for Construction Activities (Section 94.4.1)

• Public Information Signage Required (Section 94.4.5)

• Site-Specific Dust Mitigation Plan Required for Projects of

ten acres or greater in size (Section 94.4.9)

• Dust Control Monitor Required for Construction Activity

having 50 acres or more of actively Disturbed Soil (Section 94.4.11)

• 20% Opacity Limit on Dust Emissions {Section 94.5.2 &

94.6.8(d)}

• 100-yard Plume Limit {Section 94.6.8(b)}

• Controls Required on site at all times, whether or not

Construction Activity is occurring (Section 94.5.3)

• Backfilling (Section 94 Handbook, CST 1)

• Blasting – Abrasive (Section 94 Handbook, CST 2)

• Blasting – Soil and Rock (Section 94 Handbook, CST 3) 36% (2001)

71% (2002+)4-44 Table 4-14

Significant PM 10 Sources Control Measures 24-Hour Standard (continued)

Source Category BACM-Control Measures Overall

Reduction Percentage

with

Control

Measures

Highway

Construction Project-Wind

Erosion (continued) • Clearing and Grubbing (Section 94 Handbook, CST 4)

• Clearing Forms (Section 94 Handbook, CST 5)

• Crushing (Section 94 Handbook, CST 6)

• Cut and Fill (Section 94 Handbook, CST 7)

• Demolitions – Implosion (Section 94 Handbook, CST 8)

• Demolitions – Mechanical/Manual (Section 94 Handbook,

CST 9)

• Disturbed Land Large Tracts (Section 94 Handbook, CST

11)

• Dust Suppressant, Dust Palliative, and Surfactant Selection

and Use (Section 94 Handbook, CST 12)

• Landscaping (Section 94 Handbook, CST 14)

• Paving/Subgrade Preparation (Section 94 Handbook, CST 15)

• Screening (Section 94 Handbook, CST 16)

• Staging Areas (Section 94 Handbook, CST 17)

• Stockpiles (Section 94 Handbook, CST 18)

• Traffic – Construction Related (Section 94 Handbook, CST

20)

• Trenching (Section 94 Handbook, CST 21)

• Truck Loading (Section 94 Handbook, CST 22)

Vehicle

Erosion-Race

Activities • Prevent Motor Vehicle Access and Stabilize Disturbed Surface {Section 90.2.1.1(a)}.

• Stabilize Disturbed Surface greater than 5,000 sq.ft. with

Gravel or Dust Palliatives {Section 90.2.1.1(b)}. 40% (2001)

79% (2002+)

Wind ErosionRace

Activities • Prevent Motor Vehicle Access and Stabilize Disturbed Surface {Section 90.2.1.1(a)}.

• Stabilize Disturbed surface greater than 5,000 sq.ft. with

Gravel or Dust Palliatives {Section 90.2.1.1(b)}. 36% (2001)

72% (2002+)4-45 4.5.2.1 Control Measur es For Disturbed Vacant Lands (24-hour Standard)

4.5.2.1.1 Sources Controlled: 1) Publicly and privately owned disturbed open areas and vacant lots. 2) Weed abatement by discing and bl ading of open areas and

vacant lots.

4.5.2.1.2 Implementation Schedule: All requirements became effective on January 1, 2001.

4.5.2.1.3 Description of Control Strategy: This control measure is implem ented through Section 90 of the Air Quality Regulations. This regulation requires the implementation of controls for preventing fugitive dust emissions from disturbed open areas and vacant lots with a cumulative disturbed area larger than 5,000 square feet, and for preventing fugitive dust emissions for weed abatement by di scing and blading of open areas and vacant lots of 5,000 square feet or larger.

An analysis of Clark County Assessor Records (See Appendix L) determined that less than one percent of vacant land within the BLM disposal boundary was from parcels smaller than 5,000 square feet.

Control measures applicable to disturbed areas consist of the following:

• Preventing motor vehicle access and stabilizing the disturbed surfaces; or

• Applying dust palliatives to disturbed surfaces; or

• Applying and maintaining a uniform surface gravel cover over the disturbed surfaces; or

• Applying and maintaining alternative control approved by U. S. EPA.

Where motor vehicle trespass is occurring on open areas and vacant lots greater than 5,000 square feet, regardless of the amount of cumulative disturbed surface area, owners must take steps to prevent trespass and stabilize the surfac e. Where greater than 5,000 square feet of cumu latively disturbed surface exists, if owners have not implemented the latter control, they must apply dust palliative (not just water) or gravel. Prevention of Fugitive

Dust Emissions4-46 Control measures for discing and blading consist of the following:

• Applying water before and during discing and blading for weeds; and

• Stabilizing after weed abatement.

Test methods for determining compliance with the regulation’s stabilization r equirements consist of the following:

• Drop ball test; or

• Threshold friction velocity test; or

• Rock test method for non-erodible surface

elements.

4.5.2.1.4 Technical Feasi bility and Environmental Impacts: Similar requirements for disturbed open areas and vacant lots, and for discing and blading, have been implemented in Maricopa County. The major difference between the Clark County r egulatory program and the Maricopa County program is that the Clark County Regulations do not provide fo r revegetation as a control option. Revegetation was not considered to be a generally effective control option in the Las Vegas Valley due to the area’s meteorology. Rainfall occurs very sporadically in the Valley and averages only 4.13 inches per year over an extended time period, as detailed in Chapter 3. Th is makes establishing selfsustaining vegetation generally infeasible as a method of controlling fugitive dust, unless special efforts are made to ensure adequate application of water and

interim soil stabilization. However, the regulation does allow for revegetation and ot her control options notexplicitly provided for in the regulation on a case-bycase basis, subject to approval by the Control Officer and the U. S. EPA Region IX Administrator.

Use of windbreaks as a cont rol measure for controlling dust from disturbed vacant lands are also subject to approval by the Control Officer and the U. S. EPA Region IX Administrator under this regulation. This

allows for review of factor s that may affect windbreak performance such as vehicular access, severity of soil disturbance, and windbreak orientation. Revegetation Not a Control Option

Windbreaks as a

Control Measure4-47 Clark County is proposing to amend AQR Section 90 to require large property owner s managing 10,000 acres or more to develope vacant l and stabilization plans. For example, BLM is using satellite data to identify parcels with potential disturbance and hiring an employee to routinely inspect parcels. Nellis Air Force Base has hired a consultant to test their parcels and develop an inspection plan. The public works departments from the

various entities have also been contacted by AQD staff and are beginning to develop pl ans of their own. These voluntary measures allow the AQD staff to prioritize the property owners and work with the owners of the largest

number of acres first.

The controls of choice under this regulation will generally be vehicular access controls and the application of dust suppressant s. A number of classes of dust suppressant products are in large-scale use both in the Las Vegas Valley and throughout the United States. They are generally considered to be environmentally innocuous. However, field and laboratory studies evaluati ng the long-term potential adverse impacts of these products on soil and water are limited, and no studies to evaluate these impacts have been conducted to date in the Las Vegas Valley. Because it is recognized that the requirements set forth in this regulation will signifi cantly increase the use of these dust suppressant pr oducts, Clark County has committed to facilitating and parti cipating in research to

address these issues. The SIP commitment for this

research is in Section 4.8.2.1.

One environmental impact of commonly used dust suppressant materials is the decrease in the permeability of treated soil su rfaces and, as a result,

increased water runoff duri ng storm events. Although the products protect treated areas from water erosion

and reduce downstream siltati on from these areas, the increased surface flow may result in additional flood potential downstream. T he CCDCP will work with the Clark County Flood Control Dis trict to further evaluate these impacts.

4.5.2.1.5 Emission Reductions: All emission reduction computations are based on t he 2006 attainment year for
the 24-hour NAAQS. The control measure applies Dust Suppressants as

a Control Measure

Water Runoff a

Concern with the Use of Dust Suppressants4-48 to the PM 10 emission source category “Disturbed Vacant Lands/Unpaved Parking Lots” wit h a total of 19.3 tons per day of uncontrolled PM 10 emissions coming from

976 acres of disturbed vacant land. Control measures and emission reductions for unpaved parking lots are addressed under the unpaved parking lots section. The emission reduction, rule penetration, rule effectiveness,

and overall reduction for this control measure are detailed in Appendix L, Tabl e L-2, and are shown below:

• Emission Reduction 91 percent;

• Rule Penetration 99 percent;

• Rule Effectiveness 80 percent; and

• Overall Control Reduction 72 percent;

Applying these overall control reductions to the 2006

uncontrolled emissions for this source category yields the following emission reductions:

• Baseline Emissions: 19.3 TPD

• Controlled Emissions: 13.9 TPD

• Emission Reductions: 5.4 TPD

4.5.2.1.6 Control Measure Costs: A range of costs has

been calculated for this cont rol measure due to the following factors:

• The rule allows a number of alternative control options that may differ widely in cost;

• The cost for a given option may vary considerably with the size of area to be treated and onsite impacts such as vehicular traffic; and

• Specific site conditions, such as soil type may significantly impact costs.

The following control measure cost and assumptions were utilized in developing cost effectiveness estimates:

• Fencing Cost 14 –Acre per year (based on cost of renting fencing): $2,000;

• Stabilization Cost 15 – Acre per application: $500 to $1,500;

14 Memorandum #08-00 to Clark Count y Health District Board of Health, May 25, 2000

15 Ibid Disturbed Vacant Land

Control Measure

Effectiveness

Stabilizing Unstable

Vacant Land Is a CostEffective Control

Measure4-49 • Number of Applications per year: one to three (assume less expensive material will need to be applied more frequently);

• Cost Range per acre per year: $500 to $2,000;

and

• Cost of Enforcement: $540,540.

The public cost of enforcem ent must also be considered when calculating control measure cost effectiveness.

As noted in the discussion of commitments for additional Air Quality Division (AQD) enfor cement staffing levels in this chapter, the total cost per year of this expanded effort, with the exception of certain administrative costs, is $780,000. 16 Administrative costs are assumed to be ten percent. It is antici pated that 63 per cent of the enhanced enforcement effort will be applied to disturbed vacant land compliance. It is estimated that the total enforcement cost per year attributed to this control measure will be $540,540. 17

The number of acres of di sturbed open areas or vacant lots, including unpaved parking lo ts, that are subject to

these controls are estimated to be 976 acres in the 2006 24-Hour Valley-Wide Emission Inventory (Table E-9). This acreage is multiplied by the low and high control cost per acre ($500 and $2000) to calculate the control measure cost per year. Enfo rcement cost per year is added to the low and high control costs to get the total control costs range per year. These total costs were divided by 365 to get the low and high end total control cost per day. Dividing these numbers by the emission reductions achieved (5.4 tons per day) yields the cost

effectiveness for this control measure.

The Clark County Health District Board of Health has adopted Section 90 of the Air Quality Regulations as

RACM and BACM for this em ission source category.

16 Naylor, M.H., Workplan for PM 10 Resources Commitment, Prepared for Clark County Health Dist rict Board of Health, July 11,

2000.

17 The estimated cost for enforcing Section 90 is based on the assumption that 63 percent of the new enforcement cost will be

allocated to Section 90. Unaccounted administrative costs are estimated to be 10 percent of the operational cost. Therefore,

Section 90 enforcement costs are calculated as follows: $780,000x0.63x1.10=$540,540.4-50 Low High

Control

Measure

Cost/Year $488,000 $1,952,00

Enforcement

Cost/Year $540,540 $540,540

Total Control

Cost/Year $1,028,540 $2,492,540

Total Cost Per Day $2,818 $ 6,829

Cost

Effectiveness $522 per ton $1,265 per ton

4.5.2.2 Control Measures For Unpaved Parking Lots (24-Hour Standard)

4.5.2.2.1 Sources Controlled: Unpaved parking lots.

4.5.2.2.2 Implementation Schedule: Control measures must be applied to new parking lots constructed after June 22, 2000. Control measures must be applied to existing par king lots by July 1, 2001.

4.5.2.2.3 Description of Control Strategy: This regulation requires the implementation of controls for preventing fugitive dust emissions from unpaved parking lots that are used for parki ng, maneuvering, or storing motor vehicles. Parking lots that are utilized intermittently, for a period of 35 days or less during the calendar year, may implement the controls set forth in this regulation only during t he period that the parking lot is utilized for vehicle parking. It should be noted, however, that an intermittent-use parking lot would become subject to Secti on 90 of the Air Quality Regulations during periods the lot was not utilized for vehicle parking.

Control measures applicable to unpaved parking lots consist of the following:

• Paving; or

• Applying and maintaining dust palliatives; or Unpaved Parking

Lots Control

Measures4-51 • Applying and maintaining dust palliatives on traffic lanes and applying and maintaining surface gravel to a dept h of two inches on the parking areas; or

• Applying and maintaining alternative controls approved by U. S. EPA.

Stabilization standards include the following:

• Complying with a 20 percent opacity requirement;

and

• Maintaining silt loading of no more than 0.33 ounces per square foot; or

• Maintaining silt content of no more than eight percent.

Test methods for determining compliance with the

control measures and stab ilization standards include an opacity test method and a silt content test method.

4.5.2.2.4 Technical Feasi bility and Environmental Impacts: The control measures and stabilization criteria required under this regulation have been implemented in Maricopa County. The Clark County regulation does not permit the use of gravel as a control measure for travel lanes in unpaved parki ng lots. The requirement that gravel be maintained at a depth of two inches is also unique to the Clark C ounty Regulation. The total area of unpaved parking lots is relatively small and

these facilities were therefor e inventoried with disturbed open areas. This was done in part because of the difficulty in differentiating between unpaved parking lots and disturbed open areas in many cases. For those unpaved parking facilities that are utilized on a regular basis, paving will probably be the most cost-effective option. It is also expected that in response to the adoption of Section 92, land use planning agencies will not be able to issue variances for paving requirements for future development projects. Where paving requirements have been previously deferred, it is not anticipated that additional deferrals will be granted for existing projects, given the fact that the Section 92 requirements supersede the County and Local Planning Code requirements.

Thus, increased use of dust suppressant products Paving Most CostEffective Option4-52 under the provisions of this regulation is expected to be limited. Dust suppressant products would primarily be limited to intermittently us ed parking facilities and other existing unpaved parking facilities as an interimcompliance measure until more permanent and costeffective paving can be financed.

4.5.2.2.5 Emission Reductions: Because the extent of unpaved parking lots affected by this regulation has not been determined on a valley-wide basis, emission reductions from this regul ation have been calculated using acreage of unpaved parki ng from the two “worst case” micro-scale areas that contained unpaved parking. A total of 21 acres of unpaved parking was

found in the Pittman micro- scale area and 18 acres ofunpaved parking was found in the Craig Road microscale area. The emission reductions, rule penetration, rule effectiveness, and overa ll reduction are detailed in Appendix L and shown below:

• Emission Reductions-Wind: 91 percent;

• Emission Reductions-Vehicle: 60 percent;

• Rule Penetration-Wind: 99 percent;

• Rule Penetration-Vehicle: 100 percent;

• Rule Effectiveness-Wind: 80 percent;

• Rule Effectiveness-Vehicle: 80 percent;

• Overall Reduction-Wind : 72 percent; and

• Overall Reduction-Vehicle: 48 percent.

Applying these overall control reductions to the

calculated emissions from the 39 acres of unpaved parking in the two inventory areas yields the following

emission reductions:

• Baseline Emissions (Wind): 1.62 TPD;

• Controlled Emissions (Wind): 0.45 TPD;

• Emission Reductions (Wind): 1.17 TPD;

• Baseline Emissions (Vehicle): 0.034 TPD;

• Controlled Emissions (V ehicle): 0.018 TPD;

and

• Emission Reductions (Vehicle): 0.016 TPD.

4.5.2.2.6 Control Measure Costs: A range of costs

has been calculated for this control measure due to the following factors: Use of Dust Suppressants Will Be

Limited

Emission Reductions

Calculated from

“Worst Case” Areas4-53 • The rule allows several alternative control options that may differ significantly in cost;

• The cost for a given option may vary considerably with the size, frequency of use, and intensity of use of the parking lot to be treated; and

• Specific site conditions, such as soil type, may significantly impact costs.

The following control measure costs per acre and assumptions were utilized in developing cost

effectiveness estimates:

• Annual Control Measure Cost (Paving): $1,722 to $4,300;

• Annual Control Measure Cost (Dust Palliatives): $1,000 to $2,000; and

• Annual Control Cost Range: $1,000 to $4,300.

The public cost of enforcing the requirements for unpaved parking lots cannot be accurately separated from the cost of complianc e enforcement of disturbed open areas and vacant land, but are expected to be a relatively small part of the $540,540 annual enforcement cost for this source category. The public cost of compliance enforcement is, t herefore, not considered in this cost assessment for unpaved parking lots.

The cost effectiveness of th is control measure for windgenerated emissions is calculated as follows. The number of acres of unpaved par king lots from the microscale areas is 39 acres. This acreage is multiplied by the low and high annual cont rol cost per acre ($1000 and $4,300) to get the control measure cost per year. This control cost is divided by 365 to get the low and high end control cost per day . Dividing these numbers by the wind erosion emission reductions achieved (1.17 tons per day) gives the low and high end cost

effectiveness from this cont rol measure for wind erosion

emissions.

Low High

Control Measure Cost/year $39,000 $167,700

Control Measure Cost/day $106.85 $459.45

Emission Reductions 1.17 TPD 1.17 TPD

Cost Effectiveness $91 per ton $393 per ton4-54 The cost effectiveness of this control measure for vehicle-generated emissions is calculated as follows. The number of acres of unpaved parking lots from the micro-scale areas is 39 acres. This acreage is multiplied by the low and hi gh annual control cost per acre ($1000 and $4,300) to get the control measure cost per year. This control cost is divided by 365 to get the low and high end control cost per day. Dividing these numbers by the vehicle-gener ated emission reductions achieved (0.016 tons per day) gives the low and high

end cost effectiveness from this control measure for vehicle-generated emissions.

Low High

Control Measure Cost/year $39,000 $167,700

Control Measure Cost/day $106.85 $459.45

Emission Reductions 0.016 TPD 0.016 TPD

Cost Effectiveness $6,678 per

ton $28,716 per

ton

The Clark County Health District Board of Health has adopted Section 92 of the Air Quality Regulations as RACM and BACM for this emission source category.

4.5.2.3 Control Measures For Construction Activities (24-hour Standard)

4.5.2.3.1 Sources Controlled: Construction activities

and related emissions.

4.5.2.3.2 Implementation Schedule: These control measures must be implemented on construction sites beginning on January 1, 2001.

4.5.2.3.3 Description of Control Strategy: Primary

elements of the control measur es set forth in Section 94 of the Air Quality Regul ations and the companion

Section 94 Handbook for Be st Management Practices (BMP) are the use of site-specific and phase-specific dust control plans and activity -specific and soil-specific control measure options for each dust-generating activity. This regulatory pr ogram is designed to facilitate pre-planning for dust control and the integration of dust Controlling Dust from

Construction Activities4-55 control activities with other work at construction sites while allowing the flexibility to employ the best and most cost-effective control measures for each specific job site. Clark County staff belie ves that this regulatory program provides a major advancement over other programs that have been im plemented to regulate fugitive dust from construction activities and sets the BACM/Most Stringent Measure benchmark.

Section 94 of the Air Qualit y Regulations (Section 94) contains specific regulat ory requirements, including permit requirements, stab ilization requirements, administrative requirements, and performance

standards. The Sectio n 94 Handbook is a compendium of BMP that has been approved by the Clark County Board of Health for controlling dust from construction activities under varying site-specific conditions. Implementing the appropriate BMPs

contained in the Section 94 Handbook will result in compliance with the rule; and the Section 94 Handbook methodologies and procedures will be the basis for enforceable dust permit conditions.

This regulatory program is t he result of the cumulative efforts of the Advisory Committee, the Clark County Board of Health, the constr uction industry coalition, CCDCP staff, AQD staff, and the U. S. EPA. It represents a successful ex ample of what can be achieved through a consensus-based regulatory development process. The Advisory Committee finalized a Request for Proposals (RFP) for review of the Clark County Health District air quality program and development of BMP for constr uction activities in July 1999. Proposals for this work were accepted through August 27, 1999 and the Advisory Committee

recommended that the firm of Dames & Moore be retained to perform this wo rk on September 10, 1999. The Clark County Board of Health approved this recommendation. The construction industry was interviewed by Dames & Moore and provided many insightful comments on the cu rrent regulatory program. The Advisory Committee provided assistance in the development of BMP for cont rolling dust. The Advisory Committee accepted the Dame s & Moore reports as complete on May 5, 2000 and the BMP for Construction Activities Developed4-56 Clark County Board of Health accepted these reports on May 25, 2000. Section 94 of the Air Quality Regulations and the com panion Section 94 Handbook for BMP implement the concepts and the control measures recommended in the Dames & Moore reports.

The Section 94 Regulation in cludes the following permit requirements for construction activities:

• Dust control permits are required for construction

activities on sites of 0. 25 acres or larger; or

• Trenching projects of 100 feet or greater in length; or

• Demolition of structures 1,000 square feet or larger; and

• A dust control permit and a site-specific dust mitigation plan is required for construction

activities on sites of ten acres or more.

As noted above, a site-specific dust mitigation plan must be provided for all constructi on projects of ten acres or greater. For projects of less than ten acres, a sitespecific dust mitigation plan is not required, but appropriate BMPs from the Section 94 Handbook must be incorporated into the permit application and approved by AQD staff. W here dust mitigation plans are submitted, the plans are subject to review and approval by AQD staff. T he regulation also obligates permit holders to ensure that contractors and subcontractors abide by the conditions of the approved dust control permit and dust mitigation plan. For a further description of the dust control plan and permit requirements, see Section 6.3.3.3.

Section 94 implements the following general requirements and standards fo r construction activities:

• Posting signs which advise the public who to call in the event of a dust pr oblem and where to call to report a dust violation; and

• Employing Best Management Practices (BMP)

from the Section 94 Handbook as specified in the approved dust control permit and dust mitigation plan; and General Requirements for

Construction

Activities4-57 • Requiring a dust control coordinator (monitor) for construction projects having 50 acres or more of actively disturbed area; and

• Handling, transporting, or storing material in a manner that prevents dust plumes from exceeding 20 percent opacity; and

• Maintaining disturbed soil in a condition to minimize wind erosion and particulate emissions 24 hours a day, seven days a week; and

• Ceasing construction activities when wind

conditions cause dust emissions to exceed 20 percent opacity; and

• Maintaining dust control until the construction site is completely stabilized by landscaping, paving, or the application and maintenance of a dust palliative or other effective long-term stabilization;

and

• Notifying the AQD within ten days after completion of a construction project in order to allow the AQD to verify that stabilization requirements have been met.

Section 94 contains t he following enforcement standards and requirements:

• Requires a surety bond to cover the cost of the

dust control measures when three or more violations occur within 180 days; and

• Establishes that non-compliance with BMP as set forth in the approved dust control permit or dust mitigation plan is a violation of the AQD’s regulations; and

• Provides that a permit may be revoked or suspended when three notices of violation have been issued; and

• Establishes that generation of a dust plume extending more than 100 ya rds is a violation; and

• Establishes that the failu re to immediately clean up mud and dirt that is tracked out onto a paved

road and that extends a cumulative distance of 50 feet or more, or th e failure to clean up any track out by the end of the work day, is a violation; and

• Establishes that allowing a dust plume to exceed an opacity of 20 percent is a violation; and

• Establishes that failure to maintain project soils Section 94

Enforcement

Standards and Requirements4-58 with adequate crusting is a violation;

• Provides that the Clark County Control Officer may, after giving due notice, take appropriate

corrective action to rem edy a dust problem where the owner or operator fails to do so and assess the cost to the responsible party; and

• (Proposed) Establishes t hat the generation of a dust plume more than 100 f eet is a violation.

Section 94 also contains the following miscellaneous and administrative requirements:

• Construction site superintendents or designated alternatives and water truck operators are required to attend the AQD dust control class every three years; and

• Records of construction site self-inspections must be kept for one year or for a six-month period following the project’s completion, whichever is longer; and

• Where chemical or organic soil stabilizers are applied, records must indicate the type of product applied, vendor name, and label instructions for approved usage; and the method, frequency, concentration, and quantit y of application.

Test methods contained in Section 94 for determining compliance with the control measures and stabilization standards consist of an opac ity test method and a drop ball test method. Clark County has contracted with Converse Consultants to develop and field-test improved alternative test me thods for monitoring visible

emissions.

The Section 94 Handbook of Best Management Practices for Dust Control gr ew out of efforts to define

what control measures were appropriate for different construction activities within the Las Vegas Valley. Due to differences in soil types and the need to control water usage, a “one size fits all” approach was not considered effective and had not worked well in the past. The Section 94 Handbook provides BMPs for dust control that are activity-specific and which may be implemented on a site-specific and phase-specific basis, considering the type of soil at a particu lar site or location and the soils’ potential to emit fugitive dust. Currently , AQD Section 94

Miscellaneous and

Administrative Requirements

Section 94 Handbook

Defines Dust Control

Measures for Different

Construction Activities4-59staff are working to develop dust mitigation recordkeeping forms that are easy to use, yet detailed enough to demonstrate compliance with each site-specific dust mitigation plan. When fina lized, these forms will be incorporated into the Section 94 Handbook. The regulatory requirements for construction activities are

contained in Section 94 of the Air Qualit y Regulations

and are described above.

In the Section 94 Handbook, soil types are classified into five categories (high, moderately high, moderately low, low, and slight) based on their Particulate Emission Potential (PEP). PEP is deter mined by soil silt content (measured by the soil perc entage that will pass through a 200-mesh sieve) and optimum moisture content for compaction (measured by the percent moisture necessary to maximize compaction of the soil). The

Section 94 Handbook contains a decision flow chart using these two parameters, optimum moisture content and silt content, to calculate PEP for Las Vegas soils. Maps of Clark County and Las Vegas that delineate the five PEP categories are included in the Handbook for projects where the optimum moisture content or silt

content is not known. Use of site-specific geotechnical reports or preliminary soil studies are highly encouraged when developing dust mitigation plans for submittal to
the AQD.

Subsections of the Secti on 94 Handbook list the BMP alphabetically by construction activity and then by soil PEP category. Within most construction activity categories there are multiple BMP options which may be implemented to meet the Se ction 94 requirements for each activity. All BMPs for each activity that will occur

at a construction site must be identified in the dust mitigation plan submitted to the AQD or will be specified in the dust control permit that is issued by AQD for the construction project. Dust mitigation plans must be approved by the AQD prior to the issuance of a dust control permit. The BMP selected to meet the requirements of Section 94 must take into account the soil PEP for the area in which the construction activity

will occur.

The following categories of construction activities are covered by BMP: Soil Types

Described in

Section 94

Handbook

BMPs Must Be

Identified for Dust

Mitigation Plans4-60 • Backfilling;

• Blasting – Abrasive;

• Blasting – Soil and Rock;

• Clearing and Grubbing;

• Clearing Forms;

• Crushing Operations;

• Cut and Fill Operations;

• Demolition – Implosion;

• Demolition – Mechanical/Hand;

• Disturbed Soil;

• Disturbed Land – Large Tracts;

• Dust Suppressant, Dust Palliative, and Surfactant Selection and Use;

• Importing Soil, Rock, and Other Bulk Materials;

• Landscaping;

• Paving/Subgrade Preparation;

• Screening;

• Staging Area;

• Stockpiles;

• Track Out Prevention;

• Traffic – Construction Related;

• Trenching Operations; and

• Truck Loading.

Control measures not curr ently listed in the Handbook may be proposed in the dust mitigation plan. Such measures will be reviewed by the District’s staff and evaluated according to the following criteria:

• The control technique is a new or alternative technology that has been shown to be of equal or greater effectiveness in meeting the requirements than the existing BMP; or

• Site logistics do not permi t the implementation of

the control measure as written; or

• The owner/operator demonstr ates that the controlmeasure is technically infeasible due to sitespecific or material-specific conditions in that its implementation will not reduce fugitive dust

emissions.

At least one of the above cr iteria must be met before permit deviations from specific soil category BMPs are

allowed. Non-Listed Control Measures May Be Proposed and

Evaluated4-61 4.5.2.3.4 Technical Feasi bility and Environmental Impacts: The regulatory approach implemented by this regulation has been utilized for controlling emissions from stationary sources for many years, but has not been applied to area-source fugitive dust emissions until now. The regulation implements site-specific permitting for large construction sites. The permitting process is designed to allow flexibility in crafting a dust control plan while ensuri ng that appropriate control measures are applied to all dust-producing activities

associated with a constructi on project. Clark County believes that this regulatory approach will lead to future improvements to dust contro l technology in the same way that this regulatory approach has facilitated improved control technology for stationary sources.

In order to facilitate rule implementation and encourage development of improved methods of dust control for construction activities, the AQD has committed to reviewing and, as appropria te, updating the Section 94 Handbook every six months.

All of the BMPs provided in the Section 94 Handbook have been effectively employ ed by the construction industry in either the Las V egas Valley or other parts of

the southwestern United St ates. The unique component

of the Section 94 Handbook is the soil characterizations used to predict a soil’s PEP category. This was developed utilizing data from 150 soil samples. Since its publication in the Da mes & Moore reports, PEP categorization has been empl oyed by the construction industry in the Las Vegas Valley and has been found by the industry to accurately refl ect the potential severity of fugitive dust emissions and a soil’s response to various control measures. County staff also observed the comparative dustiness of unpaved roads in the Las Vegas Valley and found that t he relative dustiness of the road tracked the PEP categor y of the road surface.

However, County staff be lieves that additional

refinement of the PEP index would be desirable. If feasible, County staff may co llaborate with the research scientists who developed the PEP concept in publishing a paper in a peer-reviewed Permitting Process Allows Flexibility in

Dust Control Plan

This Approach Will

Lead to Future Improvements in Dust

Control

AQD Will Update Handbook Every Six

Months

Handbook’s PEP Categories a Unique

Factor

County Believes

Additional Refinement of PEP Categories

Desirable4-62 scientific journal. In additi on to getting the concept peer reviewed, and increasing our knowledge base, a journal

article would facilitate the utilization of the PEP concept

in other nonattainment areas.

This regulation will result in the increased use of dust palliatives in the Las Vegas Valley. In addition, the regulation will require signi ficant increases in the

amount of surfactants and ta ckifiers that are applied during land clearing, grubbing, and earth-moving operations. The potential impac ts of this increased use of dust palliatives and suppr essants in the Las Vegas Valley are detailed above under the review of disturbed

vacant land. As descri bed under the SIP commitments section in this chapter, Clark County is committed to participating in the funding and coordination of research to determine the potentia l adverse environmental impacts from the long-term use of dust suppressant

materials.

4.5.2.3.5 Emission Reductions: All emission reduction computations are based on t he 2006 attainment year for
the 24-hour NAAQS. The rule applies to the PM 10 emission source categories, “Construction Activity Fugitive Dust” and “Windblow n Construction Dust.” “Highway Construction Activity Fugitive Dust” and “Highway Construction Proj ects-Wind Erosion” were broken out separately from ot her construction activities in the Chapter 3 emission inventories for transportation conformity purposes, but have been included with the other construction activities for the purposes of this analysis. Control factors for highway-related

construction activities are i dentical to those for other types of construction. This control measure applies to all of Clark County, so the actual reductions achieved are greater than those applic able to the Las Vegas Valley and factored into the attainment demonstration. The emission reductions, rule penetration, rule effectiveness, and overall reduction for the year 2006

are shown below.

Emission Reductions:

• Construction Activity Fugitive Dust: 87 percent

• Windblown Construction Dust: 91 percent Dust Palliative Use Will Increase in Valley

Emission

Reductions
Quantified for Several Categories4-63 Rule Penetration:

• Windblown Construction Dust: 98 percent

• Construction Activity Fugi tive Dust: 98 percent; Rule Effectiveness (2006):

• Construction Activity Fugitive Dust: 80 percent

• Windblown Construction Dust: 80 percent Overall Reduction (2006):

• Construction Activity Fugitive Dust: 68 percent

• Windblown Construction Dust: 71 percent

Applying these overall control reductions to the

uncontrolled emissions fr om the 14,587 acres under construction in 2006 (Table E-5) provides the controlled

emissions and emission reductions shown below for this source category:

• Baseline Emissions (Activity): 45.6 TPD;

• Controlled Emissions (A ctivity): 14.6 TPD;

• Emission Reductions (Activity): 31.0 TPD;

• Baseline Emissions (Wind): 97.5 TPD;

• Controlled Emissions (Wind): 29.4 TPD;

and

• Emission Reductions (Wind): 68.1 TPD.

4.5.2.3.6 Control Measure Costs: Dames & Moore 18

found that the cost of c ontrolling dust during grading on a 40-acre parcel with soils categorized as “Low” for PEP would typically be $1,700 per day, or $43 per acre per day. This cost is predicated on the application of 200,000 gallons of water. The water application rate and cost would double for a parcel with soils classified as “High” for PEP. Therefore, the cost per acre per day for controlling dust from gr ading operations ranges from $43 per acre per day to $86 per acre per day. The projected acreage of construction occurring valley-wide in 2006 is 14,587 acres as shown in Appendix E, Table E-5. However, not all of this construction acreage is active during the entire year as discussed in Appendix B. Using the average length of construction by type of construction project, the number of acres on any given

18 Dames & Moore, An Evaluation of Incorporating Best Management Practices into the Construction Activities Program

, document 44499-001-128, prepared fo r the Clark County Health District Board of Health, p. 13. Costs of Controlling

Dust4-64 day can be calculated. The acreage under construction

in 2006 is 225 acres.

Grading is the most dust-intensive phase of a construction project. Cost estimates for dust control during other phases of a cons truction project under this control measure have not been developed by industry and are currently not known. Once cost factors have been developed by industry for compliance, a more complete cost analysis can be completed. Because of the unavailability of cost fa ctors for other requirements in the control measure, the co st analysis for this control measure is based on cost effectiveness per acre for

control of dust from grading operations and will overestimate the compliance cost for most other types

of construction activities.

The cost of enforcement to the local air agency is
calculated as follows. The cost of additional AQD enforcement staffing levels for the implementation of this regulation is calculated to be $285,714. 19 The perday enforcement cost is calculated by dividing this figure by 365, and is approximately $783.

The cost of compliance is calculated by multiplying the cost per day of control by the number of acres per day that must be controlled each day. The low and high control costs range is calculated as follows:

Low Cost: $43 x 225 acres/day = $9,675 High Cost: $80 x 225 acres/day = $19,350

Adding the cost per day of enf orcement to the total low and high cost of controls gives the total cost of implementing the control meas ure. These low and high

costs for control measur e implementation are $10,458 and $20,132 respectively. Div iding the total control measure implementation cost by the emission reductions achieved by the control measure gives the

cost effectiveness for t he control measure.

19 The estimated cost for enforcing Section 94 is based on the assumption that 33 percent of the new enforcement cost will be allocated to enforcing Section 94. Unaccounted administrative costs are estimated to be 10 percent of the operational cost. Therefore, Section 90 enforcement costs are calculated as follows: $780,000x0.3x1.10=$285,7144-65 These values are set forth below:

Low High

Total Cost Per Day $10,458 $20,132

Emission Reductions (Wind and Activity) 99.1 99.1

Cost Effectiveness $106 per ton $203 per ton

The Clark County Health District Board of Health has adopted Section 94 of the AQR as RACM and BACM for this emission source category.

4.5.2.4 Control Measures For Paved Road Dust (24- Hour Standard)

4.5.2.4.1 Sources Controlled: Paved roads

4.5.2.4.2 Implementation Schedule: The requirements of these c ontrol measures became effective on January 1, 2000.

4.5.2.4.3 Description of Control Strategy: These control measures set requi rements for design standards for paved road shoulders and medians and set PM efficiency requirements for st reet sweeping equipment.

The control measures fo r unpaved shoulders and street sweeping equipment are im plemented under Section 93
of the AQR. The control m easure for reducing track out

of mud and dirt from c onstruction sites onto paved roads is implemented under Se ction 94 of the AQR. The purpose of the sh oulder and median design requirements is to reduce silt loading on paved road

travel lane surfaces from mud and dirt track on. The U. S. EPA Fugitive Dust BACM guidance document 20
suggests that other benefit s from shoulder or curb improvements are reductions in the transfer of dust from exposed road shoulders to r oad surfaces by vehicle turbulence, wind erosion, and water erosion. An authoritative peer-reviewed study conducted by the

Desert Research Institute in Merced County, California,

found that the actual entrain ment occurring from vehicle wakes was limited and was only measurable from large

20 Fugitive Dust Background Document , supra, p 3-11 Paved Road Dust

Control Measures4-66 vehicles traveling at 50 to 60 mph. 21 The primary emphasis of these paved road design standards is, therefore, prevention of mud and dirt track out on to the travel lanes of paved road surfaces.

The regulation requires paving or stabilization of fourfoot shoulders beyond the travel lane or the installation of curbs adjacent to the paved section of road. The regulation also requires t hat medians be paved or stabilized, or be construct ed with curbing. Most medians constructed in the Las Vegas Valley already comply with this standard. The regulation provides that medians located in limited access freeway rights-of-way that exceed 5, 000 square feet are subject to the provisions of Section 90 (Disturbed Open Areas)

in lieu of Section 93.

Preventative control measures for preventing the track

out of mud and dirt from unpaved shoulders consist of the following minimum design standards for paved

roads:

• Constructing paved shoulders with a minimum width of four feet adjac ent to the paved travel lane; or

• (Proposed) Constructing paved road shoulders

with a minimum width of eight feet adjacent to travel lanes on new roads with 3,000 ADT or greater; or

• Applying and maintaining dust palliatives for a

minimum width of four feet adjacent to the travel lane; or

• Constructing curbing adjacent to the paved travel lane; or

• Constructing paved median for paved roads.

Preventative control meas ures for preventing the

track out of mud and dirt from unpaved medians consist of the following minimum design standards for paved roads:

• Construct medians with paving; or

21 Watson, J.G., et. al., Effectiveness Demonstration of Fugitive

Dust Control Methods for Pub lic Unpaved Roads and Unpaved

Shoulders of Paved Roads , DRI Document No. 685-5200.1F1, Desert Research Institute, Reno, Nevada, p 9-2 Medians, Curbs

Paved or Stabilized

Preventative Control Measures for Unpaved

Shoulders

Preventative

Control Measures for Unpaved

Medians4-67 • Apply and maintain dust palliatives; or

• Construct curbing on the median adjacent to

the traffic lane.

Stabilization standards for dus t palliative applications consist of the following:

• Complying with a 20 percent opacity requirement;

and

• Maintaining silt loading of no more than 0.33 ounces per square foot.

Test methods for determining compliance with the stabilization standards include an opacity test method

and a silt content test method.

Section 93 of the AQR sets standards that must be incorporated into any new or modified sections of paved roads during construction. In addition, the public agencies having jurisdiction over public roads in the nonattainment area have committed to developing a plan by February 15, 2002 for upgrading all existing roads to meet the requirements of Section 93 by December 31, 2006. Based on this commitment, it is assumed that all paved roads in the Las Vegas Valley will be in compliance with the Section 93 standards by

2006. In the event a road is discovered that does not meet the requirements of Section 93 and is not included in an agency’s plan, then the road must be brought into compliance with the AQR Section 93 requirements within 365 days following the issuance of a corrective

action order. If a road is included in an agency’s plan but is not scheduled for improvement in a timely fashion, AQD will work with the agency to reprioritize the road.

Public works agencies will ensur e the stabilization of the existing inventory of unpav ed shoulders of paved road by the end of 2006. Plans will be developed through the following process.

1. Each entity will identify the roadways that have a paved section less than 28’, which is the minimalacceptable width for two travel lanes and two fourfoot paved shoulders.4-68 2. Once the inventory is complete, the entities will then compare the inventory to their capital improvement program and developer agreements to determine which of the roadways will be brought up to the minimal acceptable width standard or full improvement standards over the next six years.

3. For those roadways that are not to be improved over the next five years, a schedule will be developed for bringing them up to appropriate local standards by

the end of 2006. The acc eptable standard will be at a minimum either a 28’ or 32’ paved section. As part of the inventory effort, car counts on the roadways and silt loading measurem ents of the paved travel lane will be taken on all candidate roadways to determine their contribution to the inventory of PM 10 attributable to unstabilized shoulders.

The SIP commitment to stabilize unpaved shoulders is

described in Section 4.8.3.2.

This regulation also mandates the purchase or leasing

of certified PM 10 -efficient street sweepers for sweeping of paved roads or paved parking lots after January 1, 2001. This r equirement applies to both public and private operators of street sweeping equipment. The regulation references South Coast Air Quality Management District (SCAQMD) Rule 1186 certification requirements and the SCAQMD certified equipment list. The urban str eets in Clark County are swept on the average of every two weeks. Rural streets are swept somewhat less fr equently. Further details on street sweeping frequency ar e provided in Appendix J

and Section 6.3.4.4.

Clark County, the Nevada Department of Transportation, and the cities of Las Vegas, North Las Vegas, and Henderson curr ently operate a combined

total of 72 street sw eepers in the Las Vegas metropolitan area. When agencies reviewed their equipment inventories, it wa s found that most of the equipment already in use was in compliance with this regulation. Equipment lists are provided in Appendix J. Therefore, Clark County has not calculated emission

reductions from this control measure for the attainment

demonstration. Paved Road

Unstabilized

Shoulders Will Be Done by 2006

Certified PM-Efficient Street Sweepers To Be

Used for Paved Areas4-69 Clark County has developed an extensive flood control system to minimize property damage and the deposition of materials on roadways caused by storm events. As noted in Chapter 2, precipitation is limited in the Las Vegas Valley, aver aging only 4.13 inches per year. However, annual rainfall can vary substantially from year to year and from rainfall event to rainfall event. In general, rainfall events are infrequent but may result in intense precipitation. As a result, the infrastructure for handling storm water is necessarily

robust to the extent that minor storms do not generally result in significant off-si te deposition of material. The flood control program for t he area is directed by the Clark County Regional Flood Control District. The

District was created in 1986 and was charged with the responsibility of developing and implementing a comprehensive flood control master plan to alleviate flooding in Clark County. Funding has been provided through voter-approved sales taxes and General Obligation Flood Control Bonds. Since 1987 the District has funded projects tota ling over $600 million. Completed facilities include 45 detention basins and approximately 220 miles of channels, washes, and storm drains. Additionally, there are approximately $1.1 billion in flood control fa cilities identified for future funding.

The natural-event action plans or policies in place in Clark County and the cities of North Las Vegas, Las Vegas, and Henderson to deal with cleanup when a major storm event does occu r complement the work of

the Flood Control District to reduce flood damage. The plans entail mobilization of all available equipment from unaffected areas to the event location(s) and removal of heavy silt deposits as quickly as possible. Since completion of the flood c ontrol system to handle a 100- year storm is years out (pendi ng additional $1.1 billion in funding), there is still the possibility of widespread erosion and deposition from a major storm. The entity plans require quick response and focus maximum resources on the rapid clean up of roadways. These programs are document ed in Appendix J.

4.5.2.4.4 Technical Feasi bility and Environmental Impacts: Paved road shoulder and median requirements set forth in this regulation for public roads4-70 will be met in accordance with the standards in AQR Section 93. Public works agencies consider paving to

be the most cost-effective solution to stabilization over an extended period rather than the use of dust suppressants or gravel. Du st suppressants and gravel will most likely be used by public works departments as a temporary measure. Some private operators of paved roads with low traffic volumes may elect to utilize dust suppressants to meet t he requirements of this regulation. This control measure will therefore not significantly increase the use of dust suppressants.

City and county paved road dev elopment standards in the Las Vegas Valley already comply with or exceed the design standards set forth in this regulation. Paved public roads are construct ed to a lesser standard only when partial improvem ents are approved for a development project as an interim measure pending additional development in an area. Where road medians are to be incorporated into the final road design, they are almost always paved or curbed, even when partial improvem ents are authorized.

The sweeper requirements set forth in this regulation have been implemented by the SCAQMD. Initially, public works agencies expr essed concern that no exemptions were included in the regulation to allow for the purchase of broom-ty pe sweepers. The agencies noted that broom sweepers are needed for cleanup of heavy debris deposits after flood events and for certain

other task which vacuu m-type sweepers cannot perform. A review of t he updated SCAQMD-certified street sweeping equipment lis t indicated that broom sweepers, including models ut ilized by local agencies,

are now certified as PM 10 -efficient, eliminating this concern. Therefore, it is now technically feasible for an agency’s entire sweeper fleet to be certified as PM 10 - efficient.

4.5.2.4.5 Emission Reductions: All emission reduction computations are based on t he 2006 attainment year for
the 24-hour NAAQS. Becaus e a very large proportion of the existing fleet of publicly ow ned and operated street-sweeping equipment in Clark County complies with this regulation, no emission reductions have been

taken that would Paving Most CostEffective Method for

Stabilization of Dust

Sweeper Requirements4-71 otherwise be achieved through the PM 10 -efficient sweeper requirements. The emission reductions from

this control measure are reflected in the emission inventory baseline. This control measure also applies to private operators of sweepi ng equipment. The impact of this regulation on these pr ivately owned sweeping fleets is not known, but is likely to be insignificant, and was not

factored into this attainment demonstration.

Entrained/re-entrained fugi tive dust emissions from paved roads are dependent on si lt loadings deposited on all classes of paved roads from all sources and Vehicle Miles Traveled (VMT) on these roads. Reductions in silt loadings do not result in linear percentage reductions of PM 10 emissions. Because

PM 10 emissions generated from paved roads are dependent on both silt load ings and VMT for each roadway type, emission r eductions must be computed separately by VMT and silt loading for each road class. These computations are det ailed in Appendix B.

Emission reductions that occu r due to the reductions in silt loadings from these c ontrol measures must likewise be calculated separately by VMT and road type. Standard emission reductions, rule penetration, rule effectiveness, and overall reduction percentages therefore cannot be applied to these reductions in the

standard form. Emission reduction calculations for

entrained/re-entrained r oad dust are detailed in Appendix L.

The controlled and uncontroll ed entrained/re-entrained fugitive dust emission for paved roads from the 2006 valley-wide 24-hour emissi on inventory taken from Chapter 5 are as follows:

• Baseline Emissions: 161.70 TPD;

• Controlled Emissions: 114.86 TPD; and

• Emission Reductions: 46.84 TPD.

These emission reductions include reductions from silt loading from all control measures except street sweeping, including reduc ed deposition from other sources, improving unstabilized shoulders, and reduced

track out from construction activities. Sweeper Fleets Not

Factored In

Paved Road Dust Emissions Dependent

on Silt Loading and

VMT4-72 Reduced deposition of particulate matter onto paved

roads occurs from control m easures applied to disturbed open areas, construction activities, and unpaved roads. This reduced deposition onto paved roads results in lower paved road silt loadings which in turn results in

lower entrained/re-entrained PM 10 emissions from the paved roads. The weighted composite of the emission reductions from disturbed open areas, construction activities, and unpaved roads is an approximate overall reduction of 75 percent. If the silt loading value is reduced by 75 percent in proportion to emission

reductions from other sour ces, then factoring the reduced silt loading values into the paved roads emission equation would yiel d an approximate reduction of 60 percent in paved road emissions. However, a linear relationship between local fugitive dust source emissions and silt loading has not been established. Clark County has therefore estimated the reductions from roadway silt loadings gained from the reduced fugitive emissions from other sources to be 30 percent.

This estimate is based on t he professional judgment of the CCDCP air planning staff observing local conditions and is documented in Appendix L. Staff believes that

the actual reductions are lik ely to be greater, but that

this conservative estimate is warranted due to the lack of empirical data. The total PM 10 emission reductions from paved roads that are gained from reduced emissions from open areas, construction activities, and unpaved roads are detailed in Appendix L, Table L-15

and summarized below:

• Baseline Emissions: 122.58 TPD;

• Controlled Emissions: 97.92 TPD; and

• Emission Reductions: 24.66 TPD.

Note that these reductions do not include reductions from improving unpaved shoulder s or reducing track out

from construction activities.

Four roadway categories in Clark County contain road segments without improved s houlders. Based on the

Dames & Moore Silt Loadi ng Measurements study, 22 it

was determined that the silt loadings for roadways

22 Dames & Moore, Silt Loading Measurements for Clark County

Paved Roads , document 44429-001-131, prepared for the Clark County Regional Transportation Commission, March 16, 2000 Reduced PM 10 Emissions from Paved

Road Dust Not Linearly Related to Silt Loading Reduction4-73 without improved shou lders are 1.34 g/m 2 for major and minor arterials and 24.7 g/m 2 for collectors and local roadways. The respective silt loadings from Table B-15 for these roadways with improved shoulders are 1.04 g/m 2 for minor arterials, 0.49 g/m 2 for major arterials, 0.86 g/m 3 for collectors, and 1.70 g/m 3 for local streets.

As paved road shoulders are improved and silt loadings decline, it is necessary to reapportion VMT from the higher silt loading values to the lower silt loading values in computing emissions. Section 93 rule effectiveness and rule penetration were estimated at 95 percent for the improvement of exis ting unpaved shoulders. Therefore, 90 percent of r oadways that currently do not have improved shoulders would have improved shoulders in 2006. The total paved road dust emissions from this category would t herefore be calculated with 90 percent of the daily VMT traveling on roadways with improvements and ten percent traveling on roadways without improved shoulders. These emissions are detailed in Appendix L, Table L-16, and summarized

below:

• Uncontrolled Emissions -No Shoulders Improved: 37.96 TPD;

• Potentially Controlled Emissions -All Shoulders Improv ed: 13.63 TPD;

• Actual Controlled Emissions -90 percent of Shoulders Improved: 16.04 TPD;

and

• Emission Reductions: 21.92 TPD.

Actual controlled emissions are calculated from the

uncontrolled emissions and potentially controlled

emissions as follows:

Total Emissions = 0.9(13. 63 tons) + 0.1(37.96 tons) = 16.04 (tons per day).

4.5.2.4.6 Control Measure Cost: The cost of compliance with this control measure will vary depending on the control meas ure approach utilized, but

is estimated as follows:

• Cost Per Mile Per Year Using Paving: $2,500 to $25,000;4-74 • Cost Per Mile Per Day Using Paving: $6.85 to $68.49;

• Cost Per Mile Per Year Using Dust Palliatives: $1,100 to $3,200;

• Cost Per Mile Per Day Using Dust Palliatives: $3.01 to $8.77;

• Miles of Shoulder Im provements:

444 miles.

Low end and high end costs of compliance are estimated by multiplying the estimated cost of shoulder improvements by the number of miles of shoulder improvements required. T hese shoulder improvements

will be constructed under public works improvement plans and the cost of enfor cement is expected to be

minor. Enforcement cost has therefore not been

included in the total cost for implementation of this

control measure.

Low High

Total Cost per Day $1,336.44 $30,409.56

Emission

Reductions 21.92 TPD 21.92 TPD

Cost

Effectiveness $61 per ton $1,387 per ton

The Clark County Health District Board of Health has adopted Section 93 and Section 94 of the AQR as

RACM and BACM for this em ission source category.

4.5.2.5 Control Measures For Unpaved Road Dust (24-hour Standard)

4.5.2.5.1 Sources Controlled: All publicly and privately owned unpaved roads, including unpaved alleys, unpaved easement roads, and unpaved access roads.

4.5.2.5.2 Implementation Schedule: The requirements of this regulation became effective on June 22, 2000 for the construction of new publicly owned and maintained and privately owned unpaved roads. Owners and/or oper ators of existing unpaved roads having vehicular traffi c of 150 vehicle trips or more per day are required to apply control measures Paved Road Control

Costs4-75 to one-third of the total road miles by June 1, 2001; apply control measures to tw o-thirds of the total road miles by June 1, 2002; and apply control measures to all unpaved roads having vehicular traffic of 150 vehicle miles or more per day by June 1, 2003.

4.5.2.5.3 Description of Control Strategy: This regulation requires the implementation of controls for preventing fugitive dust emissions for unpaved roads. Control measures applicable to unpaved roads consist of the following:

• Paving; or

• Applying and maintaining dust palliatives; or

• Applying and maintaining alternative controls approved by U. S. EPA.

In addition, the regulation does not allow the construction of unpaved roads in public thoroughfares after June 22, 2000, unless the unpaved road is an interim component of an active paving project.

Stabilization standards include the following:

• Compliance with a 20 percent opacity requirement; and

• Maintenance of a silt loading of no more than 0.33 ounces per square foot; or

• Maintenance of silt cont ent of no greater than 6 percent.

Test methods for determining compliance with the

control measures and stab ilization standards include an opacity test method and a silt content test method.

It is estimated that approx imately 64 miles of the 259- mile total base year inv entory of publicly owned and maintained unpaved roads have 150 or more trips per day. However, this estimate is based on current traffic

counts and the actual vehicle travel may be subject to seasonal variation. In order to comply with this regulatory program, Clark C ounty and the cities of Las Vegas, North Las Vegas, and Henderson have obligated Congestion Mitigat ion and Air Quality Improvement Program (CMAQ) funds (including local match) over the next three years to pave publicly Unpaved Road

Control Measures

Entities Have Obligated CMAQ

Funds To Pave Publicly Owned Unpaved Roads4-76 owned unpaved roads. The entities settled upon paving

as the most cost-effectiv e method of addressing the

PM 10 emissions resulting from the publicly owned and maintained roadways. Even though this is the most expensive alternative, it has the lowest maintenance cost, and will provide for longer life facilities. This funding commitment will ensur e the public agencies can comply with the regulation.

It is the intention of the re spective public agencies to pave all roads with average vehi cle trips of 150 or more per day. As part of either the development of the bid package, or as part of t he construction agreement, 24- hour car counts will be obtained on each segment to be paved. During construction, silt-loading tests will be obtained for each segment. Each entity is in the process of determining t he ownership of the unpaved roadways. As these are determined, they will be placed in the database described below, and these will become the basis of the bid packages.

Clark County is in the proc ess of preparing an extranet

website that will contain information on the roads that have been designated as publicly owned and maintained which local governments will be paving. The inventory of unpaved roads was developed by the respective public works departments after extensive review of the existing roadway network. Information on the website will be available to all governmental agencies at the local, regional , state, and federal level. The SIP commitment for unpaved roads is described in

Section 4.8.3.

The miles of privately owned unpaved roads have not been inventoried in detail, but public works staff from Clark County and the cities of Las Vegas, North Las Vegas, and Henderson have found a total of 45 miles of privately owned unpaved roads in the nonattainment area. Of these, 40.5 miles are loca ted in the BLM Disposal Boundary area. None of these privately owned unpaved roads had traffic volume s greater than 50 ADT.

As set forth under the commitments section of this chapter, Clark County is committing to develop an improved inventory of t hese privately owned unpaved

roads. Inventory of Privately Owned Unpaved

Roads Show None

with Greater than 50

VMT4-77 4.5.2.5.4 Technical Feasi bility and Environmental Impacts: The control measures and stabilization criteria required under this regulation have been implemented in Maricopa County, Arizona except that the Maricopa County regulation allows the use of gravel

as a control measure. Al though gravel is listed as a control measure for unpaved roads in the Fugitive Dust Technical Information Document, 23 experience in Clark County has shown that this control measure is not effective in the Las Vegas Valley. Both Clark County and Maricopa County use similar activity thresholds for unpaved roads, except that the Maricopa Rule only applies to publicly owned unpaved roads. Both areas also have programs in place t hat will result in the paving of some unpaved roads with less than 150 ADT.

A concern of public works agencies during the development of this program was that if the time frame for implementing this control measure was shortened to one or two years, then fundi ng would not be available to implement the program. Co sts could also escalate significantly, making acquisiti on of sufficient funding

even more difficult. Co sts would be expected to increase significantly under an accelerated program

because of the limited number of contractors in the region performing this class of work. The time lines and requirements of the adopted r egulatory program are not expected to significantly inflate road paving costs.

Because public agencies ar e planning to comply with the provisions of this regulation by paving, this regulation is not expected to significantly increase the use of dust suppressant pr oducts. Incidental drainage improvements constructed with the road improvements mandated under this regulation will help to address silt loading on paved roads and st orm water runoff issues.

4.5.2.5.5 Emission Reductions: The rule applies to

the PM 10 emission source category “unpaved road dust”

with a total of 55.11 TPD of PM 10 emissions coming

23 Fugitive Dust Background Document and Technical Information

Document for Best Available Control Measures , EPA-450/2-92-004; U. S. Environmental Protection Agency; Research Triangle Park, 1992; pp 3-15, 3-16 Gravel Not Effective in Clark County

Cost Issues4-78 from 259 miles of unpaved r oads in 2006. However, 66 percent of these emissions come from 64 miles of unpaved roads having vehicle trav el of 150 or more trips per day. This source categor y contributes approximately 13.95 percent of the total valley-wide PM 10 emissions.

Paving as a control measure is calculated to provide a 99 percent emission reduction. The rule penetration for this control measure, based on the 150 or more vehicle trips per day action threshold, is:

• Rule Penetration-2001 (1/3 of all roads paved): 22 percent;

• Rule Penetration-2002 (2/3 of all roads paved): 44 percent; and

• Rule Penetration-2003 (all roads paved): 66 percent. This regulation will primarily apply to public agencies. None of the privately owned unpaved roads currently

inventoried meet the 150 ADT threshold. Public works agencies are developing a comp liance program that is subject to public review and that will allow government agencies to track program progress through the extranet. Progress reports must also be submitted to
the AQD on an annual basis. The rule effectiveness of this measure is projected to be 99 percent, due to the strength of the commitmen t, its financial backing, and the priority the agencies are giving to compliance. The overall control reduction for this source category is 65 percent.

Emission reductions from the 2006 24-hour inventory

are shown below:

• Baseline Emissions: 55.11 TPD;

• Controlled Emissions: 19.50 TPD; and

• Emission Reductions: 35.61 TPD.

4.5.2.5.6 Control Measure Costs: The following control measure cost and assumptions were utilized in developing cost effectiveness estimates:

• Paving Cost 24 - Per mile per year $50,000;

24 Per year cost calculated assuming a five-year life span for paved

roads. Unpaved Roads

Emission Reductions4-79 • Paving Cost 25 - Per mile per day: $137;

• Annual Cost of Enforc ement: $25,740; and

• Daily Cost of Enforcement: $70.

The number of miles of unpav ed roads that are subject

to this control measure is estimated to be 64 miles in the valley-wide emission inventor y. Applying the control cost of $137 per day to this road mileage results in total paving cost of $8,768 per day.

The public cost of enforce ment must be included when calculating control measure cost effectiveness. As

noted in the discussion of commitments for additional AQD enforcement staffing levels in this chapter, the total cost of this expanded effort for Sections 90 through 94, excluding certain adminis trative costs, is $780,000. 26
Adjusting for administrative cos t, it is estimated that the

total enforcement cost attribut ed to this regulation will be $25,740. 27 Dividing this amount by 365 yields the daily cost of enforcement ($70 per day). Adding the cost per day of paving and cost per day of enforcement yields the total cost per day of implementing this control

measure.

Dividing the total cost per day of control measure implementation by the emission reductions achieved per day by the control measure yi elds the cost effectiveness

for this control measure.

Paving Total Cost per Day $8,838

Emission Reductions 35.61 TPD Cost Effectiveness $248 per ton

Although this cost effectiv eness value is favorable, several issues make acceleration or expansion of this

25 Per day cost calculated by di viding per year cost by 365.

26 Naylor, M.H., Workplan for PM 10 Resources Commitment

, Prepared for Clark County Health Dist rict Board of Health, July 11,

2000.

27 The estimated cost for enforcing Section 91 is based on the assumption that 3 percent of the new enforcement cost will be

allocated to Section 91. Unaccounted administrative costs are estimated to be 10 percent of the operational cost. Therefore,

Section 91 enforcement costs are calculated as follows: $780,000x0.03x1.10=$25,740. Unpaved Roads

Control Costs4-80 program infeasible. These costs are predicated on the use of all CMAQ funding not allocated to other proposals in the Las Vegas Valley over the next three years, and do not include inte rest costs that would be incurred if the program were expanded beyond what can be financed with CMAQ funding.

The Clark County Health District Board of Health has adopted Section 91 of the Air Quality Regulations as RACM and BACM for this source category.

4.5.2.6 Control Measures For Race Tracks (24-Hour Standard)

4.5.2.6.1 Sources Controlled: Dirt race tracks on publicly and privately ow ned disturbed open areas and

vacant lots.

4.5.2.6.2 Implementation Schedule: All requirements become effective on January 1, 2001.

4.5.2.6.3 Description of Control Strategy: This control measure is implem ented through Section 90 of the Air Quality Regulations. This regulation requires the implementation of controls for preventing fugitive dust emissions from disturbed open areas and vacant lots with a cumulative disturbed area larger than 5,000 square feet. Although t he regulation does not specifically prohibit dirt ra ce tracks per se, it is not possible to allow operation of off-road vehicles, including “dirt bikes” and “a ll terrain vehicles” (ATVs) on open areas and vacant lots and remain in compliance with the regulation.

Where motor vehicle trespass is occurring on open areas and vacant lots greater than 5,000 square feet, regardless of the amount of cumulative disturbed surface area, owners must take steps to prevent trespass and stabilize the surfac e. Where greater than 5,000 square feet of cumu latively disturbed surface exists, if owners have not implemented the latter control, they must apply dust palliative (not just water) or gravel.

Control measures applicable to disturbed areas consist of the following: Expansion of this Program Is Infeasible Beyond

Current

Commitment

Dirt Race Track

Control Measures4-81 • Preventing motor vehicle access, including dirt bike and all terrain vehicle access, and stabilizing the disturbed surfaces; or

• Applying dust palliatives to disturbed surfaces; or

• Applying and maintaining a uniform surface gravel cover over the disturbed surfaces; or

• Applying and maintaining alternative control approved by U. S. EPA.

Test methods for determining compliance with the regulation’s stabilization r equirements consist of the following:

• Drop ball test; or

• Threshold friction velocity test; or

• Rock test method for non-erodible surface

elements.

4.5.2.6.4 Technical Feasi bility and Environmental Impacts: Much of the discussion under Technical Feasibility and Environmental Impacts in the Control Measures For Unpaved Parking Lots (24-Hour Standard) section is also applicable to this control

measure. As noted in that discussion, the controls of choice under this regulation will generally be vehicular access controls and the application of dust suppressants. Application of dust suppressants will not

be economical if off-road vehicle use is allowed to occur. To the extent that ATV use is presently occurring in the Las Vegas Valley urban area, their use will be sharply curtailed due to the a ssociated economic cost of

these activities under this regulation. Where property owners find that their property is impacted by ATV use,

access restrictions will be t he preferred control measure

of choice.

4.5.2.6.5 Emission Reductions: “Race tracks” were found to have significant impac ts at the Craig Road and Green Valley micro-inventory sites. These activities occurred where ATV users identified a vacant parcel that was unfenced and unposted and placed some old

tires on the site to form a “race track.” The emission reduction, rule penetration, rule effectiveness, and

overall reduction for this control measure are detailed in Appendix L and are shown below: Access Controls

Preferred Control

Measure4-82 Race Track Wind Erosion

• Emission Reduction 91percent;

• Rule Penetration 99percent;

• Rule Effectiveness 80 percent;

• Overall Control Reduction 72 percent;

Race Track Vehicles

• Emission Reduction 100 percent;

• Rule Penetration 99 percent;

• Rule Effectiveness 80 percent; and

• Overall Control Reduction 79 percent.

Applying these overall control reductions to the 2006

uncontrolled emissions for this source category yields the following emission reductions:

RACE

TRACKS Uncontrolled

Emissions Tons/Day Controlled

Emissions Tons/Day Emission

Reductions

Tons/Day

CRAIG ROAD

Wind Erosion 1.71 0.48 1.23

Emissions 0.72 0.15 0.57

GREEN VALLEY

Wind Erosion 1.08 0.30 0.78

Emissions 0.18 0.04 0.14

Off-road racing is sufficiently mi niscule in scale as to not warrant a separate cat egory in the valley-wide

inventories. To the extent that “dirt bike” and “all terrain vehicle” use disturbs open areas and vacant parcels in the urban area, they are a ccounted for in the disturbed

vacant land inventories. Developing a separate inventory for this source category is very difficult due to the sporadic nature of this activity, most of which occurs on property without the property owner’s permission. 28

28 Testimony and complaints about unauthorized off-road vehicle use were heard at a number of the workshops on disturbed vacantland and unpaved road rules. In addition, when surveying countyowned land for surface stabilizatio n, County staff observed “dirt bike” and “all terrain vehicle” use occurring in areas where this activity was clearly not authorized. Recreational Vehicle Use Is Sporadic and of

Limited Scale4-83 In reviewing BLM permits for off-road racing events on BLM land, it was found that no off-road racing events were approved by BLM in the nonattainment area duringthe past year. Currently BLM is working to establish offroad racing courses outside the nonattainment area.

Courses within the nonattain ment area are permanently

closed.

4.5.2.6.6 Control Measure Costs: The control

measure cost discussion in the Control Measures For

Disturbed Vacant Lands (24-Hour Standard) section is also applicable to this control measure.

4.5.3 Adopted Control Measures For The Annual
NAAQS

Table 4-15 (pages 4-83 – 4-88) provides a detailed list of the specific elements of the Clark County control measures adopted or implemented to achieve

attainment of the annual PM 10 NAAQS.

4.5.3.1 Control Measur es For Disturbed Vacant Lands (Annual Standard)

4.5.3.1.1Sources Controlled: 1) Publicly and privately owned disturbed open areas and vacant lots. 2) Weed abatement by discing and bl ading of open areas and

vacant lots.

4.5.3.1.2 Implementation Schedule: All requirements became effective on January 1, 2001.

4.5.3.1.3 Description of Control Strategy: See Description Of Control Strategy discussion in Control Measures For Disturbed Vacant Lands (24-Hour Standard) Section 4.5.2.1.2.

4.5.3.1.4 Technical Feasi bility and Environmental Impacts: See Technical Feasibility and Environmental Impacts discussion in Control Measures For Disturbed Vacant Lands (24-Hour Standard) Section 4.5.2.1.3. Disturbed Vacant

Lands Control

Measures4-84 Table 4-15

Significant PM 10 Sources Control Measures-Annual Standard

Source Category BACM Control Measures Overall

Reduction Percentage

with Control

Measures

Area Sources

Disturbed

Vacant

Lands • Prevent Motor Vehicle Access and Stabilize Disturbed Surface {Section 90.2.1.1(a)}

• Stabilize Disturbed Surface greater than 5,000 sq.ft. with

Gravel or Dust Palliatives {Section 90.2.1.1(b)}

• Discing or Blading areas of 5,000 square feet or larger for

weed abatement, apply water both before and during operations {Section 90.2.2.1(a),(b)}

• After Discing or Blading occurs, stabilize disturbed surfaces

with Gravel, Water, Dust Palliatives, or Paving {Section 90.2.2.1(c)} 36% (2001)

72% (2002 +)

Unpaved Parking Lots • Pave {Section 92.2.1.2(a)}

• Apply and Maintain Dust Palliatives {Section 92.2.1.2(b)}

• Apply and Maintain Dust Palliatives on Traffic Lanes and

apply surface gravel to depth of two inches on Parking Areas {Section 92.2.1.2(c)}

• (Proposed) Prohibition of new unpaved parking lots

• (Proposed) Prohibition of dust crossing property line Wind Erosion 36% (2001) 72% (2002+)

Vehicles 24% (2001) 48% (2006)

Construction Activity Fugitive

Dust • Apply Dust Suppressant (water) throughout construction site to stabilize soil (Section 94 Handbook, CST 10-l)

• Apply Dust Palliative on soils based on soil type (Section 94

Handbook, CST 12)

• Traffic Control in Construction Area (Section 94 Handbook,

CST 10-2, CST 20-1, CST 19 Requirements & CST19-7)

• Use tarps or other suitable enclosures on haul truck (Section

94 Handbook, CST 13-1)

• Stabilize surface with materials that will prevent track out of

mud and dirt to the Paved section, with wheel shakers, wheel washers {Section 94 Handbook, CST 19-3, 19-4 and Section 94.6.8.(c)}

• Permits Required for Construction Activities (Section 94.4.1)

• Public Information Signage Required (Section 94.4.5)

• Site-Specific Dust Mitigation Plan Required for Projects of

ten acres or greater in size (Section 94.4.9)

• Dust Control Monitor Required for Construction Activity

having 50 acres or more of actively Disturbed Soil (Section 94.4.11) 34% (2001)

68% (2003+)4-85 Source Category BACM-Control Measures Overall

Reduction Percentage

with Control

Measures

Construction Activity Fugitive

Dust (continued) • 20% Opacity Limit on Dust Emissions {Section 94.5.2 & 94.6.8(d)}

• 100-yard Plume Limit {Section 94.6.8(b)}

• (Proposed) 100-foot plume limit

• (Proposed) Prohibition of dust crossing property line

• Controls Required on site at all times, whether or not

Construction Activity is occurring (Section 94.5.3)

• Backfilling (Section 94 Handbook, CST 1)

• Blasting – Abrasive (Section 94 Handbook, CST 2)

• Blasting – Soil and Rock (Section 94 Handbook, CST 3)

• Clearing and Grubbing (Section 94 Handbook, CST 4)

• Clearing Forms (Section 94 Handbook, CST 5)

• Crushing (Section 94 Handbook, CST 6)

• Cut and Fill (Section 94 Handbook, CST 7)

• Demolitions – Implosion (Section 94 Handbook, CST 8)

• Demolitions – Mechanical/Manual (Section 94 Handbook,

CST 9)

• Disturbed Land Large Tracts (Section 94 Handbook, CST

11)

• Dust Suppressant, Dust Palliative, and Surfactant Selection

and Use (Section 94 Handbook, CST 12)

• Landscaping (Section 94 Handbook, CST 14)

• Paving/Subgrade Preparation (Section 94 Handbook, CST

15)

• Screening (Section 94 Handbook, CST 16)

• Staging Areas (Section 94 Handbook, CST 17)

• Stockpiles (Section 94 Handbook, CST 18)

• Traffic – Construction Related (Section 94 Handbook, CST

20)

• Trenching (Section 94 Handbook, CST 21)

• Truck Loading (Section 94 Handbook, CST 22)

• (Proposed) Prohibition on use of dry rotary brushes or

blower devices to clean up track out Table 4-15

Significant PM 10 Sources Control Measures-Annual Standard (continued)4-86 Source Category BACM-Control Measures Overall

Reduction Percentage

with Control

Measures

Windblown

Construction

Dust • Apply Dust Suppressant (water) throughout construction site to stabilize soil (Section 94 Handbook, CST 10-l)

• Apply Dust Palliative on soils based on soil type (Section 94

Handbook, CST 12)

• Traffic Control in Construction Area (Section 94 Handbook,

CST 10-2, CST 20-1, CST 19 Requirements & CST19-7)

• Use tarps or other suitable enclosures on haul truck (Section

94 Handbook, CST 13-1)

• Stabilize surface with materials that will prevent track out of

mud and dirt to the Paved section, with wheel shakers, wheel washers {Section 94 Handbook, CST 19-3, 19-4 and Section 94.6.8.(c)}

• Permits Required for Construction Activities (Section 94.4.1)

• Public Information Signage Required (Section 94.4.5)

• Site Specific Dust Mitigation Plan Required for Projects of ten

acres or greater in size (Section 94.4.9)

• Dust Control Monitor Required for Construction Activity having

50 acres or more of actively Disturbed Soil (Section 94.4.11)

• 20% Opacity Limit on Dust Emissions {Section 94.5.2 &

94.6.8(d)}

• 100 yard Plume Limit {Section 94.6.8(b)}

• Controls Required on site at all times, whether or not

Construction Activity is occurring (Section 94.5.3)

• Backfilling (Section 94 Handbook, CST 1)

• Blasting – Abrasive (Section 94 Handbook, CST 2)

• Blasting – Soil and Rock (Section 94 Handbook, CST 3)

• Clearing and Grubbing (Section 94 Handbook, CST 4)

• Clearing Forms (Section 94 Handbook, CST 5)

• Crushing (Section 94 Handbook, CST 6)

• Cut and Fill (Section 94 Handbook, CST 7)

• Demolitions – Implosion (Section 94 Handbook, CST 8)

• Demolitions – Mechanical/Manual (Section 94 Handbook, CST

9)

• Disturbed Land Large Tracts (Section 94 Handbook, CST 11)

• Dust Suppressant, Dust Palliative, and Surfactant Selection

and Use (Section 94 Handbook, CST 12)

• Landscaping (Section 94 Handbook, CST 14)

• Paving/Subgrade Preparation (Section 94 Handbook, CST 15)

• Screening (Section 94 Handbook, CST 16)

• Staging Areas (Section 94 Handbook, CST 17) 36% (2001)

71% (2002+) Table 4-15

Significant PM 10 Sources Control Measures-Annual Standard ( continued )4-87 Source Category BACM Control Measures Overall

Reduction Percentage

with Control

Measures

Windblown

Construction

Dust (continued) • Stockpiles (Section 94 Handbook, CST 18)

• Traffic – Construction Related (Section 94 Handbook, CST 20)

• Trenching (Section 94 Handbook, CST 21)

• Truck Loading (Section 94 Handbook, CST 22)

On-Road Mobile Sources

Paved Road

Dust (includes

Construction

Track Out) • Pave or Stabilize four feet of Shoulders (Section 93.2.1.1)

• (Proposed) Stabilize eight feet of shoulders on new roads

with 3,000 ADT or greater

• Pave or Stabilize Medians with solid paving across median

(Section 93.2.1.4)

• Use PM-Efficient Street Sweepers (Section 93.2.3.1)

• Prevent mud and dirt track out with wheel shakers, or wheel

washers must be employed at Construction Sites to prevent mud and dirt track out onto paved roads (Section 94 Handbook, CST 19-3 & CST 19-4)

• Clean up mud and dirt track out once every 24 hours and

when track out extends more than 50 feet N/A 29

Unpaved

Road Dust • Pave Unpaved Roads With Traffic ≥ 150 ADT {Section 91.2.1.3(a)}; or

• Apply and Maintain Dust Palliatives to Unpaved Roads With

Traffic ≥ 150 ADT {Section 91.2.1.3(b)} Paving PhaseIn (2001) – 22% (2002) – 44% (2003+) – 65%

Highway

Construction Project

Activities • Apply Dust Suppressant (water) throughout construction site to stabilize soil (Section 94 Handbook, CST 10-l)

• Apply Dust Palliative on soils based on soil type (Section 94

Handbook, CST 12)

• Traffic Control in Construction Area (Section 94 Handbook,

CST 10-2, CST 20-1, CST 19 Requirements & CST19-7)

• Use tarps or other suitable enclosures on haul truck (Section

94 Handbook, CST 13-1)

• Stabilize surface with materials that will prevent track out of

mud and dirt to the Paved section, with wheel shakers, wheel washers {Section 94 Handbook, CST 19-3, 19-4 and Section 94.6.8.(c)}

• Permits Required for Construction Activities (Section 94.4.1)

• Public Information Signage Required (Section 94.4.5)

• Site-Specific Dust Mitigation Plan Required for Projects of ten

acres or greater in size (Section 94.4.9) 34% (2001)

63% (2003 +)

29 No emission reductions taken for PM-Efficient Street Sweepers. Because there is not a linear relationship between silt loadin g and emission rates, the actual emission reductions will vary with the roadway mix in each inventory area. Table 4-15

Significant PM 10 Sources Control Measures-Annual Standard ( continued )4-88 Source Category BACM-Control Measures Overall

Reduction Percentage

with Control

Measures

Highway

Construction Project

Activities (continued) • Dust Control Monitor Required for Construction Activity having 50 acres or more of actively Disturbed Soil (Section 94.4.11)

• 20% Opacity Limit on Dust Emissions {Section 94.5.2 &

94.6.8(d)}

• 100 yard Plume Limit {Section 94.6.8(b)}

• (Proposed) 100-foot plume limit

• (Proposed) Prohibition of dust crossing property line

• Controls Required on site at all times, whether or not

Construction Activity is occurring (Section 94.5.3)

• Backfilling (Section 94 Handbook, CST 1)

• Blasting – Abrasive (Section 94 Handbook, CST 2)

• Blasting – Soil and Rock (Section 94 Handbook, CST 3)

• Clearing and Grubbing (Section 94 Handbook, CST 4)

• Clearing Forms (Section 94 Handbook, CST 5)

• Crushing (Section 94 Handbook, CST 6)

• Cut and Fill (Section 94 Handbook, CST 7)

• Demolitions – Implosion (Section 94 Handbook, CST 8)

• Demolitions – Mechanical/Manual (Section 94 Handbook,

CST 9)

• Disturbed Land Large Tracts (Section 94 Handbook, CST 11)

• Dust Suppressant, Dust Palliative, and Surfactant Selection

and Use (Section 94 Handbook, CST 12)

• Landscaping (Section 94 Handbook, CST 14)

• Paving/Subgrade Preparation (Section 94 Handbook, CST

15)

• Screening (Section 94 Handbook, CST 16)

• Staging Areas (Section 94 Handbook, CST 17)

• Stockpiles (Section 94 Handbook, CST 18)

• Traffic – Construction Related (Section 94 Handbook, CST

20)

• Trenching (Section 94 Handbook, CST 21)

• Truck Loading (Section 94 Handbook, CST 22)

• (Proposed) Prohibition on use of dry rotary brushes or blower

devices for clean up of track out

• (Proposed) Acquire only vacuum type chip seal equipment
Highway

Construction Project-Wind

Erosion • Apply Dust Suppressant (water) throughout construction site to stabilize soil (Section 94 Handbook, CST 10-l)

• Apply Dust Palliative on soils based on soil type (Section 94

Handbook, CST 12) 36% (2001)

71% (2002 +) Table 4-15

Significant PM 10 Sources Control Measures-Annual Standard (continued)4-89 Table 4-15

Significant PM 10 Sources Control Measures-Annual Standard (continued)

Source Category BACM-Control Measures Overall

Reduction Percentage

with Control

Measures

Highway

Construction Project-Wind

Erosion (continued) • Traffic Control in Construction Area (Section 94 Handbook, CST 10-2, CST 20-1, CST 19 Requirements & CST19-7)

• Use tarps or other suitable enclosures on haul truck (Section

94 Handbook, CST 13-1)

• Stabilize surface with materials that will prevent track out of

mud and dirt to the Paved section, with wheel shakers, wheel washers {Section 94 Handbook, CST 19-3, 19-4 and Section 94.6.8.(c)}

• Permits Required for Construction Activities (Section 94.4.1)

• Public Information Signage Required (Section 94.4.5)

• Site-Specific Dust Mitigation Plan Required for Projects of ten

acres or greater in size (Section 94.4.9)

• Dust Control Monitor Required for Construction Activity

having 50 acres or more of actively Disturbed Soil (Section 94.4.11)

• 20% Opacity Limit on Dust Emissions {Section 94.5.2 &

94.6.8(d)}

• 100 yard Plume Limit {Section 94.6.8(b)}

• Controls Required on site at all times, whether or not

Construction Activity is occurring (Section 94.5.3)

• Backfilling (Section 94 Handbook, CST 1)

• Blasting – Abrasive (Section 94 Handbook, CST 2)

• Blasting – Soil and Rock (Section 94 Handbook, CST 3)

• Clearing and Grubbing (Section 94 Handbook, CST 4)

• Clearing Forms (Section 94 Handbook, CST 5)

• Crushing (Section 94 Handbook, CST 6)

• Cut and Fill (Section 94 Handbook, CST 7)

• Demolitions – Implosion (Section 94 Handbook, CST 8)

• Demolitions – Mechanical/Manual (Section 94 Handbook,

CST 9)

• Disturbed Land Large Tracts (Section 94 Handbook, CST 11)

• Dust Suppressant, Dust Palliative, and Surfactant Selection

and Use (Section 94 Handbook, CST 12)

• Landscaping (Section 94 Handbook, CST 14)

• Paving/Subgrade Preparation (Section 94 Handbook, CST 15)

• Screening (Section 94 Handbook, CST 16)

• Staging Areas (Section 94 Handbook, CST 17)4-90 Table 4-15

Significant PM 10 Sources Control Measures-Annual Standard (continued)

Source Category BACM-Control Measures Overall

Reduction Percentage

with Control

Measures

Highway

Construction Project-Wind

Erosion (continued) • Stockpiles (Section 94 Handbook, CST 18)

• Traffic – Construction Related (Section 94 Handbook, CST

20)

• Trenching (Section 94 Handbook, CST 21)

• Truck Loading (Section 94 Handbook, CST 22)

4.5.3.1.5 Emission Reductions: All emission reduction computations are based on t he 2001 attainment year for
the annual NAAQS. The control measure applies to the PM 10 emission source category

“Disturbed Vacant Lands/Unpaved Parking Lots” with a total of 48,500 TPY of uncontrolled PM 10 emissions coming from 2,430 acres of disturbed vacant land. Control measures and emission reductions for unpaved parking lots are addressed under the unpaved parking lots section. The emission reduction, rule penetration, rule effectiveness, and overall reduction for this control

measure are detailed in Appendix L and are shown

below:

• Emission Reduction 91 percent;

• Rule Penetration 99 percent;

• Rule Effectiveness 40 percent; and

• Overall Control Reduction 36 percent.

Applying these overall control reduction to the 2001 emissions for this source category yields the following

emission reductions:

• Baseline Emissions: 33,100 TPY

• Controlled Emissions: 21,184 TPY

• Emission Reductions: 11,916 TPY Emission Reductions

from Disturbed Vacant

Land4-91 4.5.3.1.6 Control Measure Costs: A range of costs has been calculated for this regulation due to the following

factors:

• The rule allows a number of alternative control options that may differ widely in cost;

• The cost for a given option may vary considerably with the size of area to be treated and onsite impacts such as vehicular traffic; and

• Specific site conditions such as soil type may significantly impact costs.

The following control measure costs and assumptions were utilized in developing cost effectiveness estimates:

• Fencing Cost 30 –Acre per year (based on cost of renting fencing) $2,000;

• Stabilization Cost 31 – Acre per application: $500 to $1,500;

• Number of Applications per year: one to three (assume less expensive material will need to be applied more frequently);

• Cost Range per acre per year: $500 to $2,000;

and

• Cost of Enforcement: $540,540.

Public cost of enforcement must also be considered when calculating control measure cost effectiveness. As

noted in the discussion of commitments for additional Air Quality Division (AQD) enfor cement staffing levels in this chapter, the total cost per year of this expanded effort, with the exception of certain administrative costs, is $780,000. 32 Adjusting for the administrative cost and assuming 63 percent of the enhanced enforcement effort will be applied to disturbed vacant lands, it is

estimated that the total enf orcement cost per year

30 Memorandum #08-00 to Clark Count y Health District Board of Health, May 25, 2000

31 Ibid.

32 Naylor, M.H., Workplan for PM 10 Resources Commitment

, Prepared for Clark County Health Dist rict Board of Health, July 11,

2000. Disturbed Vacant Land

Control Costs4-92 attributed to this control measure will be $540,540. 33

The number of acres of di sturbed open areas or vacant lots that are subject to these control measures is estimated to be 12,766 acres 34 in the 2001 annual valley-wide emission inventor y (Appendix E, Table E-9). This acreage is multiplied by the low and high cost per acre ($500 and $2,000) to calc ulate the control measure cost per year. Enforcement cost per year is added to the low end and high end contro l cost to calculate the total control cost per year . Dividing these numbers by the emission reductions (11, 916 TPY) yields the cost

effectiveness for this control measure.

Therefore, applying the abov e control cost to the acreage subject to the cont rol measure on the per-day basis yields the following cost factors.

Low High

Control Measure

Cost/Year $6,383,000 $25,532,000

Enforcement Cost/Year $540,540 $540,540 Total Control Cost/Year $6,923,540 $26,072,540

Cost Effectiveness $581 per

ton $2,188 per

ton

The Clark County Health District Board of Health has adopted Section 90 of the Air Quality Regulations as

RACM and BACM for this em ission source category.

4.5.3.2 Control Measures For Unpaved Parking Lots (Annual Standard)

4.5.3.2.1 Sources Controlled: Unpaved parking lots.

4.5.3.2.2 Implementation Schedule: Control measures must be applied to new parking lots constructed after June 22, 2000. Control measures must be applied to existing par king lots by July 1, 2001.

33 The estimated cost for enforcing Section 90 is based on the assumption that 63 percent of the new enforcement cost will be

allocated to Section 90. Unaccounted administrative costs are estimated to be ten percent of the operational cost. Therefore,

Section 90 enforcement costs are calculated as follows: $780,000x0.63x1.10=$540,540

34 This acreage includes unpaved parking lots.4-93 4.5.3.2.3 Description of Control Strategy: See Description Of Control Strategy discussion in Control Measures For Unpaved Parking Lots (24-Hour Standard) Section 4.5.2.2.3.

4.5.3.2.4 Technical Feasi bility and Environmental Impacts: See Technical Feasibility and Environmental Impacts discussion in Control Measures For Unpaved Parking Lots (24-Hour Standard) Section 4.5.2.2.4.

4.5.3.2.5 Emission Reductions: Because the extent of unpaved parking lots affected by this regulation has not been determined on a valley-wide basis, emission reductions from this regulat ion were calculated using acreage of unpaved parking from the two “worst case” micro-scale areas that contained unpaved parking. A total of 21 acres of unpaved parking was

found in the Pittman micro- scale area and 18 acres ofunpaved parking was found in the Craig Road microscale area. The emission reductions, rule penetration, rule effectiveness, and overa ll reduction are detailed in Appendix L and shown below for the year 2001:

• Emission Reductions-Wind: 91 percent;

• Emission Reductions-Vehicle: 60 percent;

• Rule Penetration-Wind: 99 percent;

• Rule Penetration-Vehicle: 100 percent;

• Rule Effectiveness-Wind: 40 percent;

• Rule Effectiveness-Vehicle 40 percent;

• Overall Reduction-Wind: 36 percent; and

• Overall Reduction-Vehicle: 24 percent.

The uncontrolled baseline emissions, controlled emissions, and emission reductions for wind and vehicle

emissions from the 39 ac res of unpaved parking are

listed below. Emissions from the two micro-scale sites were calculated on a daily basis for the design day; therefore, the emission s have been “annualized” by multiplying by 365. These emission estimates are

assumed to overestimate emissions from this source category.

• Baseline Emissions (Wind): 591.3 TPY

• Controlled Emissions (Wind): 378.4 TPY

• Emission Reductions (Wind): 212.9 TPY Unpaved Parking Lots

Control Measures4-94 • Baseline Emissions (Vehicle): 12.41 TPY

• Controlled Emissions (V ehicle): 9.41 TPY

• Emission Reductions (Vehicle): 2.99 TPY

4.5.3.2.6 Control Measure Costs: A range of costs

has been calculated for this control measure due to the following factors:

• The rule allows several alternative control options that may differ significantly in cost;

• The cost for a given option may vary considerably with the size, frequency of use, and intensity of use of the parking lot to be treated; and

• Specific site conditions, such as soil type, may significantly impact costs.

The following control measure costs and assumptions were utilized in developing cost-effectiveness estimates:

• Annual Control Measure Cost (Paving): $1,722 to $4,300;

• Annual Control Measure Cost (Dust Palliatives): $1,000 to $2,000; and

• Annual Control Cost R ange: $1,000 to $4,300.

The public cost of enforcing the requirements for unpaved parking lots cannot be accurately separated from the cost of complianc e enforcement of disturbed open areas and vacant land, but are expected to be a relatively small part of the $540,540 annual enforcement cost for this source category. The public cost of compliance enforcement is not considered in this cost assessment for unpaved parking lots.

The cost effectiveness of th is control measure for windgenerated emissions is calculated as follows. The number of acres of unpaved par king lots from the microscale areas is 39 acres. This acreage is multiplied by the low and high annual cont rol cost per acre ($1000 and $4,300) to get the control measure cost per year. Dividing these numbers by the wind erosion emission reductions achieved (212.9 tons per year) gives the low and high end cost effectiv eness from this control measure for wind- generated emissions from unpaved parking lots. Emission Reductions from Unpaved Parking

Lots4-95 Low High

Control Measure

Cost/Year $39,000 $167,700

Emission Reductions 212.9 TPY 212.9 TPY

Cost Effectiveness $183 per ton $788 per ton

The cost effectiveness of this control measure for vehicle-generated emissions is calculated as follows. The number of acres of unpaved parking lots from the micro-scale areas is 39 acres. This acreage is multiplied by the low and hi gh annual control cost per acre ($1000 and $4,300) to get the control measure cost per year. Dividing these numbers by the vehiclegenerated emission reductions achieved (2.99 tons per year) gives the low and high end cost effectiveness from

this control measure for vehicle-generated emissions.

Low High

Control Measure

Cost/Year $39,000 $167,700

Emission Reductions 2.99 TPY 2.99 TPY

Cost Effectiveness $13,044 per

ton $56,087 per

ton

The Clark County Health District Board of Health has adopted Section 92 of the Air Quality Regulations as

RACM and BACM for this em ission source category.

4.5.3.3 Control Measures For Construction Activities (Annual Standard)

4.5.3.3.1 Sources Controlled: Construction activities

and related emissions.

4.5.3.3.2 Implementation Schedule: These control measures must be implemented on construction sites beginning on January 1, 2001.

4.5.3.3.3 Description of Control Strategy: See Description Of Control Strategy discussion in Control Measures For Construction Activities (24-Hour Standard) Section 4.5.2.3.3. Cost Effectiveness for Unpaved Parking Lots

Construction Activities

Control Measures4-96 4.5.3.3.4 Technical Feasi bility and Environmental Impacts: See Technical Feasibility and Environmental Impacts discussion in Control Measures For Construction Activities (24-Hour Standard) Section

4.5.2.3.4.

4.5.3.3.5 Emission Reductions: All emission reduction computations are based on t he 2001 attainment year for the annual NAAQS. The rule applies to the PM 10 emission source categories “Construction Activity Fugitive Dust” and “Windblow n Construction Dust.” “Highway Construction Activity Fugitive Dust” and “Highway Construction Proj ects-Wind Erosion” were broken out separately from ot her construction activities in the Chapter 3 emission inventories for transportation conformity purposes, but have been included with the other construction activities for the purposes of this analysis. Control factors for highway-related

construction activities are ident ical to those for other types of construction. This control measure applies to all of Clark County, so the actual reductions achieved are greater than those applic able to the Las Vegas Valley and factored into the attainment demonstration. The emission reductions, rule penetration, rule effectiveness, and overall reduction for the year 2001

are shown below:

Emission Reductions:

• Construction Activity F ugitive Dust: 80 percent;

• Windblown Construction Dust: 91 percent;

Rule Penetration:

• Construction Activity F ugitive Dust: 98 percent;

• Windblown Construction Dust: 98 percent; Rule Effectiveness (2001):

• Construction Activity F ugitive Dust: 40 percent;

• Windblown Construction Dust: 40 percent; Overall Reduction (2001):

• Construction Activity F ugitive Dust: 32 percent;

• Windblown Construction Dust: 36 percent; a

a As noted in Appendix L, wind erosion emissions from construction sites were calculated assuming a percentage of each construction site was already controlled under regulations (i.e., RACM) already in place and not measures adopted as part of the SIP. Therefore, the percent r eduction calculated for the4-97 SIP- adopted measures is appl ied to those portions of the site not already being cont rolled. Therefore, actual

emission reductions achi eved are less than the reductions that would be achieved by applying the

control measure to an uncontrolled source.

Applying these overall control reductions to the 2001

annual uncontrolled emissions yields the following

emission reductions:

• Baseline Emissions (Activity): 25,891 TPY

• Controlled Emissions-(Activity): 17,088 TPY

• Emission Reductions-(Activity): 8,803 TPY

• Baseline Emissions (Wind): 19,851 TPY

• Controlled Emissions -(Wind): 12,812 TPY

• Emission Reductions-(Wind): 7,039 TPY

4.5.3.3.6 Control Measure Cost: Dames & Moore 35

found that the cost of cont rolling dust during grading on a 40 acre parcel with soils categorized as “Low” for PEP would typically be $1,700 per day, or $43 per acre per day. This cost is predicated on the application of 200,000 gallons of water. The water application rate and cost would double for a parcel with soils categorized as “High” for PEP. Therefore, the cost per acre per day for controlling dust from grading operations ranges from $43 per acre per day to $86 per acre per day. The projected acreage of construction occurring valley-wide in 2001 is 22,691 acres as shown in Appendix E, Table E-5. Ho wever, not all of this construction acreage is active during the entire year as discussed in Appendix B. Using the average length of construction by type of cons truction project, the number of acres on any given day can be calculated. The acreage under construction in 2001 averages 350 acres per day.

Grading is the most dust-intensive phase of a construction project. Cost estimates for dust

35 Dames & Moore, An Evaluation of Incorporating Best Management Practices into the Construction Activities Program, document 44499-001-128, prepared fo r the Clark County Health District Board of Health, p. 13 Construction Activity

Emission Reductions

Construction Activity

Control Costs4-98 control during other phases of a construction project under this control measure have not been developed by industry and are currently not k nown. Once cost factors have been developed by industry for compliance, a more detailed cost analysis can be completed. Because of the unavailability of cost factors for other requirements in the control measure, the cost analysis

for this control measure is based on cost effectiveness per acre for control of dus t from grading operations and will overestimate the compliance cost for most other types of construction activities.

The cost of enforcement to the local air agency is
calculated as follows. The cost of additional AQD enforcement staffing levels fo r the implementation of this regulation is calcul ated to be $285,714 per year. 36
The annual cost of compliance per acre is calculated by multiplying the low and high co st per day by 365. These annual costs per acre controlled are $15,965 and $31,390 respectively. The cost of compliance is calculated by multiplying the co st per year of control by the number of acres per day that must be controlled each day. The low and high c ontrol costs are calculated

as follows:

Low Cost: $15,695 x 350 acres = $5,493,250;

and High Cost: $31,390 x 350 acres = $10,986,500.

Adding the cost per year of enforcement to the total low and high cost of controls gives the total cost of implementing the control meas ure. These low and high

costs for control meas ure implementation are $5,778,964 and $11,272,214 respectively. Dividing the total control measure impl ementation cost by the emission reductions achieved by the control measure gives the cost effectiveness for the control measure.

36 The estimated cost for enforcing Section 94 is based on the assumption that 33 percent of the new enforcement cost will be allocated to enforcing Section 94. Unaccounted administrative costs are estimated to be ten per cent of the operational cost. Therefore, Section 90 enforcement costs are calculated as follows: $780,000x0.3x1.10=$285,714.4-99 Low High Total Cost Per Day $5,778,964 $11,272,214 Emission Reductions (Wind and Activity) 15,842 tons 15,842 tons

Cost Effectiveness $365 per

ton $712 per

ton

The Clark County Health District Board of Health has adopted Section 94 of the AQR as RACM and BACM for this emission source category.

4.5.3.4 Control Measures For Paved Road Dust (Annual Standard)

4.5.3.4.1 Sources Controlled: Paved roads.

4.5.3.4.2 Implementation Schedule: The requirements of these c ontrol measures became effective on January 1, 2000.

4.5.3.4.3 Description of Control Strategy: See Description Of Control Strategy discussion in Control Measures For Paved Road Dust (24-Hour Standard)

Section 4.5.2.4.3.

4.5.3.4.4 Technical Feasi bility and Environmental Impacts: See Technical Feasib ility and Environmental Impacts discussion in Control Measures For Paved Road Dust (24-Hour Standar d) Section 4.5.2.4.4.

4.5.3.4.5 Emission Reductions: All emission reduction computations are based on t he 2001 attainment year for
the annual NAAQS. Because a very large proportion of the existing fleet of public ly owned and operated streetsweeping equipment in Clark County complies with this regulation, no emission r eductions have been taken that would otherwise be achieved through the PM 10 -efficient sweeper requirements. The emission reductions from

this control measure are reflected in the emission inventory baseline. This control measure also applies to private operators of sweepi ng equipment. The impact of this regulation on these pr ivately owned sweeping fleets is not known, but is likely to be insignificant, and was not

factored into this attainment demonstration. Paved Road Dust

Control Measures

Sweeper Fleets Not

Factored In4-100 Entrained/re-entrained fugi tive dust emissions from paved roads are dependent on si lt loadings deposited on all classes of paved roads from all sources and Vehicle Miles Traveled (VMT) on these roads. Reductions in silt loadings do not result in linear percentage reductions of PM 10 emissions. Because

PM 10 emissions generated from paved roads are dependent on both silt load ings and VMT for each roadway type, emission r eductions must be computed separately by VMT and silt loading for each road class.

The attainment demonstration for the annual standard isbased on the J. D. Smith micro-scale site. The valleywide annual emission inventor y was based on the J. D.

Smith micro-scale site. The r eduction in silt loading that

will occur in 2001 due to reduced deposition from

emissions from other source s is 15 percent. When the 15 percent silt reduction was applied to the paved road miles with improved shoulders by class and VMT mix at

the J. D. Smith micro-scale site, a ten percent reduction

in overall emissions was achi eved. In order to ensure consistency between the valley-wide 2001 annual emission inventory and the J. D. Smith attainment demonstration, the same ov erall emission reduction was applied to the paved road emissions in the valley-wide inventory. This is a c onservative approach in that applying the 15 percent silt r eduction to the valley-wide road mix would result in somewhat larger emission

reductions.

Because there were not unimproved shoulders in the J. D. Smith micro-scale site boundary, no reductions were taken in the valley-wi de emission inventory for the improvement of unimproved shoulders.

The controlled and uncontroll ed entrained/re-entrained fugitive dust emission for paved roads from the 2001 Valley-Wide Annual Emissi on Inventory that are presented in Chapter 5 and Appendix L are shown

below:

• Total Uncontrolled Paved Road Emissions: 55,350 TPY

• Total Controlled Paved Road Emissions: 50,239 TPY

• Uncontrolled Paved Road Dust Emissions: 41,115 TPY Paved Road Dust Emissions Dependent

on Silt Loading and

VMT

Emission Reductions

from Paved Roads4-101 • Controlled Paved Road Dust Emissions: 37,004 TPY

a Total uncontrolled and controlled paved road

emissions include emissions that result from unimproved shoulders throughout the valley. This

emission source was not c ontrolled in the annual 2001 valley-wide inventory in order to maintain consistency

with the J. D. Smith at tainment demonstration.

4.5.3.4.6 Control Measure Costs: No emission reduction credit was taken for improving unimproved

shoulders or for utilization of certified PM-efficient street sweeping equipment in the 2001 Annual Valley-Wide emission inventory. Theref ore, cost effectiveness of

these control measures was not evaluated.

The Clark County Health District Board of Health has adopted Section 93 and Section 94 of the AQR as

RACM and BACM for this em ission source category.

4.5.3.5 Control Measures For Unpaved Road Dust (Annual Standard)

4.5.3.5.1 Sources Controlled: All publicly and privately owned unpaved roads, including unpaved alleys, unpaved easement roads, and unpaved access

roads.

4.5.3.5.2 Implementation Schedule: The requirements of this regulation became effective on June 22, 2000 for the construction of new publicly owned and maintained and privately owned unpaved roads. Owners and/or oper ators of existing unpaved roads having vehicular traffi c of 150 vehicle trips or more per day are required to apply control measures to

one-third of the total road miles by June 1, 2001; apply

control measures to two-thirds of the total road miles by June 1, 2002; and apply control measures to all unpaved roads having vehicular traffic of 150 vehicle miles or more per day by June 1, 2003.

4.5.3.5.3 Description of Control Strategy: See Description Of Control Strategy discussion in Control Measures For Unpaved Road Dust (24-Hour Standard)

Section 4.5.2.5.3. Publicly, Privately Owned Unpaved

Roads Dust Control

Measures4-102 4.5.3.5.4 Technical Feasi bility and Environmental Impacts: See Technical Feasibility and Environmental Impacts discussion in Control Measures For Unpaved Road Dust (24-Hour Standard) Section 4.5.2.5.4.

4.5.3.5.5 Emission Reductions: The rule applies to

the PM 10 emission source category “unpaved road dust”

with total PM 10 emissions of 18,932 TPY in the PM 10 2001 Annual Valley-Wide Emission Inventory. The

attainment demonstration for the annual standard is

based on the J. D. Smith micr o-scale site. Therefore, the valley-wide annual emi ssion inventory was based on

the J. D. Smith micro-scale site. No unpaved roads with greater than 150 vehicle tr ips per day were located

within the J. D. Sm ith micro-scale in ventory area so no reduction from this source category was calculated for

the J. D. Smith annual invent ory. As the valley-wide annual attainment is based upon the attainment at the J. D. Smith monitoring station and the controls implemented within this micr o-scale area, no reduction in unpaved road dust was applied to the valley-wide annual inventory in 2001 for purposes of attainment

demonstration. This is a cons ervative estimate, as rules regarding the paving of unpaved roads over 150 vehicle trips per day will be in pl ace and enforced during 2001.

4.5.3.5.6 Control Measure Costs: No emission reduction credit was taken for paving unpaved roads in

the annual attainment demonstr ation or included in the

PM 10 2001 Annual Valley-Wide Emission Inventory. Therefore, cost effectiveness of these control measures

was not evaluated.



### 4.6 INSIGNIFICANT SOURCE CATEGORIES

The determination of source significance is based primarily on the J. D. Smit h annual inventory and the

24-hour micro-scale inv entories at the five representative sites, suppl emented by reviews of the 1998 valley-wide 24-hour emi ssion inventory, the 1998 valley-wide annual emission inventory, and Chemical Mass Balance (CMB) modeling. A significant source is

defined in U. S. EPA’s Addendum to General Preamble, 37 as a source that contributes more than five μg/m 3 to a 24-hour violati on and more than one μg/m 3 to

37 Federal Register, FRL-5052-2, August 16, 1994 Unpaved Road Dust

Emissions

Insignificant Sources

Contribute Less Than

One μ g/m 34-103 an annual violation. Sources wi th lower contributions to a violation are presumed to be de minimis.

4.6.1 De Minimis Source Categories – 24-Hour PM 10 NAAQS

Applying the above criteria, the anthropogenic source categories shown in Table 4-16 are found to be de

minimis for the 24-hour PM 10 NAAQS in the 1998 base

year.

Table 4-16

De Minimis Source Categories – 24-Hour NAAQS

SOURCE

CATEGORY Craig

Road

24-Hour (μg/m 3 ) East Flamingo

24-Hour (μg/m 3 ) Green Valley

24-Hour (μg/m 3 ) J.D.

Smith

24-Hour (μg/m 3 ) Pittman

24-Hour (μg/m 3 ) 24-HourValleyWide (μg/m 3 )

STATIONARY SOURCES 3.53 0.13 1.34 0.08 3.74 Sand & Gravel Operations 0.50

Utilities – Natural Gas 0.16 Asphalt Concrete Manufacture 0.14

Industrial Processes 0.06 Other Stationary Point Sources 0.10

Small Point Sources 0.15

Residential Firewood 0.24

Residential Natural Gas 0.05

Commercial Natural Gas 0.03

Industrial Natural Gas 0.01

NG – Purchased at the sourceCarried by SWG 0.17

Structural/Vehicle/Wildfires 0.01 Charbroiling/Meat Cooking 0.60

NONROAD MOBILE SOURCES Airport Support Equipment 0.03 Commercial Equipment 0.00 Construction and Mining Equipment 0.29

Lawn & Garden Equipment 0.01 Railroad Equipment 0.01 Recreational Equipment 0.00 McCarran International Airport 0.20 Henderson Executive Airport 0.00 North Las Vegas Municipal Airport 0.02

Nellis Air Force Base 0.034-104 Table 4-16

De Minimis Source Categories – 24-Hour NAAQS (continued)

ONROAD MOBLE SOURCES

Vehicular Sulfate PM 0.32

Vehicular Tire Wear 0.07

Vehicular Brake Wear 0.11 Vehicular Exhaust (Carbon PM) 1.47 1.68 0.55 1.66 0.62 0.28

4.6.1.1 Stationary Sources As shown in Chapter 3, st ationary sources, including sand and gravel operations; natural gas-fired utility power plants; asphalt concrete plants; industrial processes; and other stat ionary sources, generated 3.29 tons per day valley-wi de during the 24-hour design day. The tonnage for this source category is projected to remain unchanged through 2006. By equating the 1998 base year 24-hour design day emission total of 931.95 tons per day with the design concentration (which occurred in 1998) of 281 μ g/m 3 and allowing for the background concentration of 10.5 μ g/m 3 , the

contribution of all stationar y source emissions to the design day concentration is calculated to be 0.95 μ g/m 3

. Stationary point sources are projected to contribute the

same PM 10 mass to the 24-hour design day in 2006.

At the micro-scale level, a review of the design day

micro-inventories indicat ed that stationary source emissions at the Pittman (3.68 μ g/m 3 ) and Craig Road (3.53 μ g/m 3 ) monitoring sites came close to, but fell below, the U. S. EPA thre sholds of presumed significance for this source category.

The relatively constant emissions from stationary sources are predicated on 1) current trends for this source category, which show a slight decrease in emissions from 1994 to 1998; 2) the fact that BACT controls are required for new and modified sources which produce more than two tons; and 3) Lowest Achievable Emission Reductions (LAER) that are required for all major sources which have been constructed or modified after September 26,1996.4-105 Declining rates of population growth and construction activity would be expected to decrease activity levels in the sand and gravel operations and asphalt concrete manufacturing categories. To the extent that other stationary source categories may grow in proportion to the overall population, the BACT and LAER requirements will ensure that a ll stationary point source

emissions will remain at the de minimis level.

The requirements for BACT controls for potential

emissions over two tons and LAER requirements for all new and modified sources with the potential to emit

more than 70 tons of PM 10 are set forth under Section 12 of the AQR. Section 12 was formally approved by the U. S. EPA as part of the Nevada SIP on May 11, 1999. 38 In addition to a stationary source’s emission units, the Section 12 BACT requirements also apply to all fugitive emissions generated by the permitted facility. The definition of BACT found in the
first sentence of AQR Secti on 0 - Definitions, indicates that BACT is the “maximum degree of reduction foreach pollutant ... which the Control Officer, on a caseby-case basis, taking into account energy, environmental, and economic impacts and other costs,

determines is achievable ... for control of such pollutant.” Clark County inte rprets this to mean that the level of control representative of BACT for permitted sources with fugitive emissions is no less stringent than that required to meet BACM fo r those fugitive sources. Fugitive emissions at a stationary source are those not emitted through a stack or duc t and, therefore, include

PM 10 sources such as disturbed vacant lands, unpaved roads/haul roads, and track out onto paved roads. Stationary sources are requir ed to apply BACT to their fugitive dust sources to be at least as stringent as the standards in the applicable Re gulations 90, 91, 92, and

94.

The requirement to apply BACT to fugitive dust sources is established by the conditions contained in the Authority to Construct Certif icate issued by the Control Officer in accordance with the provisio ns of Section 12.

38 Federal Register, Vol. 64. No. 90, May 11, 1999, pages 25210 -

25213 BACT Required for Stationary Sources

with a Potential To

Emit Greater than Two

Tons

All Major PM 10 Sources Required To Apply

BACT or LAER4-106 All sources with the potential to emit of 70 tons or greater in the PM 10 nonattainment area are listed below:

Wells Cargo – LAER; Nevada Power-Sunrise (incl uding the St ate regulated sources) – BACT; Nevada Power-Clark – BACT; James Hardie Gypsum – BACT; Chemical Lime Henderson – BACT; Timet – BACT; and

CSR West – BACT.

Wells Cargo, Inc. is currently undergoing a permit modification that will require either BACT or LAER for all

PM 10 emission units at the facilit y. Currently, the facility

has some emission units t hat meet the BACT standard.

In addition to stationary sources, the AQD also issues permits to sources with a pot ential to emit greater than

one ton but less than 15 tons t hat are located at a site less than 365 continuous days. The sources are issued variable location permits (VLP s) and must also meet stringent control standards. The following permit conditions for VLPs are contained in AQD guidelines:

• Minimum moisture content of processed materials of 1.5 percent; and

• Haul roads controlled to 90 percent by use of water, dust suppressants, sealing or paving.

Beginning January 1, 2001 a new requirement for disturbed soil to pass the test standards adopted in
Section 90 of the AQR was added to the guidelines. Currently, the requirements for material being handled or stockpiled to have a 1.5 percent minimum moisture content and loose soil to be stabilized are being incorporated into VLP permits.

The AQD does have a progr am for minor source

emission reduction credits that is administered locally. Credits are usually generated by paving unpaved roads.

The credits are then used to offset minor source emissions by a 2-to-1 ratio as described in Section 12 of
the AQR. Credits are not pollutant specific and VLPs Also Required to

Have BACT4-107 reductions of one pollutant can be used to offset a different and sometimes unrelated pollutant. For example, emission reduction credits generated by paving a road and reducing PM 10 emissions by 100 tons

can be used to offset 50 tons of carbon monoxide emissions. This program is not used for major sources

and has not been used to determine emission inventories or as part of t he rollback modeling in this SIP. However, the requirem ent for offsets for new or modified minor sources may be a further deterrent for

an increase in emissions because emission increases would require offsets and the facility would incur additional expenses.

In addition to Section 12 of the Air Quality Regulations,

Section 445.389 of the Ne vada Administrative Code(NAC) prohibits the construction or modification of fossilfuel-powered electricit y generation plants in Hydrographic Basin 212 and t he city limits of Boulder City. This requirement will fu rther limit the potential for additional emissions from stationary sources.

Two of the source categorie s projected to increase in proportion to population grow th, structural/vehicle fires/wild fires and residential natural gas, are very small

sources that will remain far below the de minimis level. The charbroiling/meat cooking source category is larger,

but emissions from the sour ces with potential to emit greater than two tons within this category are subject to BACT requirements under Section 12.

Residential firewood combustion is projected to increase in proportion to population growth. New fireplaces are restricted to U. S. EPA Certified Phase II wood burning

stoves or cleaner alternat ive non-wood burning devices such as gas logs. These requirements are implemented through Clark County Ordi nance 1249, City of Las Vegas Ordinance 3538, City of North Las Vegas Ordinance 1020, and City of Henderson Ordinance

1997. These control measur es will prevent emissions

from this source cat egory from approaching or exceeding the de minimis source threshold level for this source category.

As detailed under the commitments section of this chapter, Clark County has committed to conducting a Minor Source

Emission Reduction

Credits Administrated Locally

State Law Prohibits

New Fossil-FuelPowered Power Plants

in the Nonattainment

Area

Residential Fireplaces

Restricted Under County Ordinance4-108 PM 10 saturation study to further evaluate the impacts of stationary sources on neighborhood scale PM 10 concentrations. If stationary sources are found to have significant impacts on neighborhood PM 10 concentrations, then Clark County will develop and adopt U. S. EPA approvable ru les that require the implementation of BACT for all stationary sources.

4.6.1.2 Nonroad Mobile The de minimis source categories in the nonroad mobile sources grouping are projected to remain relatively constant, grow in proporti on with population growth, or grow in proportion to airport activity. Of these source categories, only two contribute more then 0.03 μg/m 3 to the 1998 base year 24-hour design value. These are the construction and mining category and McCarran International Airport. Construction and mining equipment is projected to grow in proportion to population growth. This s ource category contributed 0.29 μg/m 3 to the 1998 base year 24-hour design value and is projected to contribute 0.94 μg/m 3 to the 2006 attainment year 24-hour design value. This is a conservative projection. Actual use of construction equipment by 2006 could act ually decline in proportion with the declining growth rate. Emissions from

McCarran International Ai rport contributed 0.20 μg/m 3 to the 1998 base year 24-hour design value. Emissions from McCarran will decline in 2006 due to aircraft gate

electrification and use of newer lower-emission aircraft at the facility.

4.6.1.3 Onroad Mobile

Onroad mobile de minimis sources include vehicular sulfate particulate, vehicular tire wear, vehicular brake wear, and vehicular exhaust (c arbon particulate). These contribute 0.32 μg/m 3 , 0.07 μg/m 3 , 0.11 μg/m 3 , and 0.28 μg/m 3 respectively to the 1998 base year 24-hour design value. Projected in creases in vehicle miles traveled are shown for each road category in Table E-14 of Appendix E. Vehicles are expected to produce less particulate and sulfate emissions per mile traveled in 2006 than in the 1998 base year based on emission

factors in the Mobile5b and Part5 models. These emission factors are developed using federal

automotive exhaust standards. Applying these factors,

it is found that there will be a slight decrease in Projected Emissions

of Nonroad Mobile Sources Stay Below

the Level of Significance in 2006

Vehicle Exhaust, Tire Wear, and Brake

Emissions Remain De

Minimis in 20064-109 emissions from the vehicular sulfate and vehicular exhaust categories in 2006 and a slight increase in

emissions from the tire wear and brake wear categories.

4.6.2 De Minimis Source Categories – Annual PM 10 NAAQS

Determination of source significance for the Annual

PM 10 NAAQS was based primarily on the 1998 annual micro-inventory at the J. D. Smith representative site and 1998 Base Year Valley-Wide PM 10 Annual Inventory and supplement ed by review of CMB modeling. A significant sour ce is defined in U. S. EPA’s

Addendum to General Preamble 39 as a source that contributes one μg/m 3 or more to an annual violation.

Sources with lower contributions to a violation are presumed to be de minimis.

Applying the above criteria , the source categories

shown in Table 4-17 are f ound to be de minimis for the

annual PM 10 NAAQS in the 1998 base year.

39 Federal Register, FRL-5052-2, August 16, 1994

Table 4-17

De Minimis Source Categories – Annual NAAQS

SOURCE

CATEGORY J. D. Smith Annual (μg/m 3 ) Valley-Wide Annual (μg/m 3 )

STATIONARY SOURCES 0.05 Sand & Gravel Operations 0.13

Utilities – Natural Gas 0.04 Asphalt Concrete Manufacture 0.04

Industrial Processes 0.02 Other Stationary Point Sources 0.03

Small Point Sources 0.04

Residential Firewood 0.02

Residential Natural Gas 0.01

Commercial Natural Gas 0.01

Industrial Natural Gas 0.00 NG – Purchased at the source-Carried by SWG 0.04

Structural/Vehicle/Wildfires 0.00 Charbroiling/Meat Cooking 0.16

NONROAD MOBILE SOURCES Airport Support Equipment 0.01 Commercial Equipment 0.00 Construction and Mining Equipment 0.08 Lawn & Garden Equipment 0.00 Railroad Equipment 0.004-110 Table 4-17

De Minimis Source Categories – Annual NAAQS (continued)

Recreational Equipment 0.00 McCarran International Airport 0.05 Henderson Executive Airport 0.00 North Las Vegas Municipal Airport 0.00

Nellis Air Force Base 0.01

ONROAD MOBLE SOURCES

Vehicular Sulfate PM 0.09

Vehicular Tire Wear 0.02

Vehicular Brake Wear 0.03 Vehicular Exhaust (Carbon PM) 0.29 0.08

4.6.2.1 Motor Vehicle ExhaustThere are two categories of motor vehicle exhaust: onroad and non-road. The on-road category includes tailpipe and tire wear emissions of primary PM 10 fromon-road vehicles including both gasoline and dieselpowered passenger cars, light -, medium-, and heavyduty trucks, buses, and motorcycles. The 1998 base year inventory shows tota l emissions from these sources to be 1,399 tons per year.

The non-road category includes various “off-road” equipment that use a variety of engine types and fuels. Examples are constructi on equipment; lawn and garden equipment; railroad equipmen t; recreational equipment; and airport equipment. Total PM 10 emissions from these sources in the 1998 base year inventory are 737 tons per year.

Measures to control v ehicle emissions have been implemented at the national, st ate and local level. The following describe the meas ures implemented that

reduce motor vehicle exhaust emissions in the Las Vegas Valley. Most of t he state and loca l measures were implemented to reduce carbon monoxide emissions, and are documented in the Las Vegas Valley

Carbon Monoxide State Im plementation Plan dated August, 2000. Reduced particulate emission benefits

from these measures are often negligible, and the reductions are generally not quantifiable due to

limitations in available model s, specifically the U. S.

EPA Part5 model. Motor Vehicle Exhaust Likely To Stay De

Minimis Because of

Federal Controls4-111 Since 1994, U. S. EPA st andards limited the sulfur

content of diesel fuel for on -road diesel vehicles to 0.05 percent by weight (500 pp m). Concurrently, Clark County adopted the 500 ppm lo w-sulfur diesel standard for all diesel fuel sold in Clark County (District Board of Health Regulations, Section 29, December 16, 1993). This rule, although not changing on-road diesel fuel composition, has reduced the non-road diesel fuel sulfur content by 85 percent from an uncontrolled average of approximately 3,300 ppm. The PM 10 emission benefits

from this measure and related costs cannot be calculated. Added costs, if any, are absorbed by the

users.

District Board of Health Air Quality Regulations, Section 45, September 26, 1991, limits the idling of diesel truck or diesel bus engines to no more than 15 minutes.

Nevada Administrative Code (NAC) 445B.576 restrictsvisible emissions from both gasoline and dieselpowered motor vehicles, and also prohibits idling the engine of a diesel truck or bus for more than 15 minutes. A program for the control of emissions from

motor vehicles is established in Nevada Revised

Statutes 445B.700 to 445B. 845 and implemented in NAC 445B.400-774. The following vehicle inspection programs are established under these statutes:

Light-duty motor vehicles powered by diesel engines are required to pass an annual emission test in order to be registered in Clark County. The inspection

criteria are established in Nevada Administrative Code (NAC) 445B.587, which includes a tampering inspection and an opacity test phase.

NAC 445B.737-774 addresse s the control of emissions from onroad heavy-duty motor vehicles. It establishes a program fo r random roadside smoke opacity testing utilizing the Society of Automotive Engineers Procedure SAE J1667, Snap-Acceleration Smoke Test Procedure for Heavy-Duty Diesel

Powered Vehicles. In addi tion to the smoke opacity test, criteria for inspecti on for tampered or defective

conditions are also establis hed to determine that the vehicle’s emission control system is operating correctly. Annual Smog ChecksRequired for LightDuty Motor Vehicles4-112 The State’s Motor Vehicle Inspection Maintenance Program is provided for in NAC 445B.400-735. The provisions apply to all gasol ine-powered motor vehicles, model year 1968 or later, that reside in the Las Vegas Valley.

The State Department of Mo tor Vehicles and Public Safety has committed to im plement a remote sensing program in the Las Vegas Va lley which will target 50 percent of the motor vehi cles operating in Las Vegas in 2001 and increase to 90 perc ent of the local motor vehicle fleet by 2011. 40 This commitment will provide substantial air quality benefits and assist in attaining/maintaining national ambient air quality

standards.

Additional state program s, other than vehicle inspections, established to reduce motor vehicle

emissions include:

An alternative fuel vehicle program, established under NAC 486A, which requires state and local government agencies to acquire cleaner burning alternative fuel vehicles. For fiscal year 1999-2000 the rule required all regul ated agencies to purchase qualifying alternative fuel v ehicles at the rate of 75 percent of all vehicle purchases. The rate increases to 90 percent for FY 2000-2001, and remains at 90 percent for future years.

The State Department of Motor Vehicles has established a “Smoking Vehicle Hotline” program in the Las Vegas Valley. Citizens can report smoking vehicles to the department to help identify and have repaired excessively smoking vehicles.

A lower Reid Vapor Pressure (RVP) requirement for gasoline was established in 1995 in NAC 590.065. Also a carbon monoxide control measure, this action

lowered the RVP limit of gasoline from 11.0 psi to 9.0 psi.

40 Letter from the Nevada Department of Motor Vehicles and Public Safety, August 28, 1995 Additional local

programs implemented to

reduce emissions from gasoline motor vehicles specifically

as

Alternative Fuel Program Mandated by State Law4-113 carbon monoxide control meas ures include a wintertime Clean Burning Gasoline (CBG) program and an oxygenated gasoline program.

CBG is a low-sulfur and lo w-aromatic fuel which helps to increase catalytic converter efficiency, resulting in lower CO as well as other emissions. District Board of Health Air Quality Regulations, Section 54, April 22, 1999, implemented the CBG program beginning October 1, 1999.

The Clark County oxygenated f uel program requires that all gasoline sold in the County during the winter season (October 1 to March 31) cont ain 3.5 percent oxygen by weight, the maximum amount al lowed. This mandate is being satisfied by the use of ethanol in lieu of MTBE. Air Quality Regulation, Sect ion 53, September 27, 1997, governs this program.

The Regional Transportation Commission of Clark County has implemented Tr ansportation Control Measures/Travel Demand Management (TCM/TDM) to reduce vehicle emissions and offset growth in vehicle miles traveled (VMT). The following voluntary control measures are being impl emented: employer based commuter incentive programs; telecommuting; and area-wide ridesharing programs.

In addition to these state and local measures implemented to reduce mobile source emissions, U. S. EPA has initiated or has proposed actions that will

further reduce emissions from diesel vehicles, both on and off road, in the future:

Standards for on-road heavy-duty truck and bus engines were established for model years 1987- 2003. These standards, following the reduced sulfur content requirement (500 ppm) beginning in 1994, significantly reduce PM 10 emissions and some NO
x . In 1997, U. S. EPA adopted new standards for the 2004 model heavy-duty engines , with the goal of further reducing NO
x emissions.

In May 2000, U. S. EPA announced proposed emission standards for model year 2007 and later heavy-duty highway engines. The proposal includes Wintertime Clean Burning Gasoline Program Helps To

Reduce Sulfur

Emissions and Increase Catalytic

Converter Efficiency

RTC Has Implemented Transportation

Control Measures

Heavy-Duty Diesel

Truck and Bus Engine Standards4-114 two components: 1) diesel fuel regulation, and 2) emission standards. The fuel provisions would

reduce the sulfur content in on-highway diesel fuel to 15 ppm, down from the cu rrent 500 ppm, beginning in 2006. New engine standards would be phased in beginning in 2007. The super-low-sulfur diesel is the “technology enabler” necessary to the further development of advanced exhaust emission technologies that will reduce particulate matter emissions by 90 percent and NO
x by 95 percent in

2030.

U. S. EPA’s off-road engine regulations are

structured as a three-ti ered progression to low emissions. Each tier involves a phase in (by horsepower rating) over several years. Tier 1 standards phase in from 1996 to 2000. A more stringent Tier 2 standard for all engine sizes take effect from 2001 to 2006, and yet more stringent Tier 3 standards for engines rated over 50 hp phase in

from 2006 to 2008. The Tier 3 standards are expected to lead to emission control technologies for off-road engines that wil l be similar to the 2004 controls for highway heavy-duty engines.

The U. S. EPA regulations t hat improve diesel fuel composition and diesel engine emissions have been

and will continue to be the most effective measures for reducing emissions of parti culate and other pollutants from diesel engines. These programs are complemented by state and local programs as

described above to contribute to the larger emission

reductions that will be r ealized from the full implementation of the U. S. EPA emission reduction programs. When U. S. EPA-approved methodologies

are available for calculati ng emission reductions from these programs, Clark Count y will complete an analysis and propose a SIP revision as appropriate.

Although there are numerous pr ograms initiated or in development to reduce vehi cle emissions, there is limited information or gui dance on methods to quantify

the benefits that will be realized in terms of particulate matter reductions and their subsequent impact on improving ambient air quality. Several research projects Stricter Heavy-Duty

Diesel Truck and Bus Engine Standards Begin in

2007

U. S. EPA Has Regulations for Diesel Fuel Composition

Several Research Projects Are Funded4-115 are funded and in progress that are expected to provide

better information about the contributions of specific sources of particulate in the Las Vegas Valley, and to identify potential control m easures to reduce future

emissions. These studies are discussed in more detail in this chapter in Section 4.7.

4.6.2.2 Stationary Sources J. D. Smith is the only m onitoring station with an annual average exceeding the NAAQS. Stationary sources in

the J. D. Smith micro-scale area generated 6.3 tons per year in the 1998 base y ear (see Chapter 3) and

contributed 0.05 μ g/m 3 to the annual design concentration. The stationary source contribution is derived by equating the J. D. Smith 1998 base year emission total of 4,511 tons per year with the design

concentration of 53 μ g/m 3 and allowing for a background concentration of 16.5 μ g/m 3 . The tonnage for this source category is projected to remain consistent through 2006. Stationary point sources would be expected to contribute a similar mass (0.05

μ g/m 3 ) of PM 10 to the annual desi gn value in 2006.

As shown in Chapter 3, stationary point sources, which include sand and gravel oper ations; natural gas-fired utility power plants; asphalt concrete plants; industrial processes; and other stat ionary sources, generated 1,201 tons per year on an annual valley wide basis in the 1998 base year. The t onnage for this source category is projected to rema in consistent through 2006. By equating the 1998 base year annual emission total of 171,755 tons per year with t he design concentration of

53 μ g/m 3 and allowing for a background concentration

of 16.5 μ g/m 3 , total stationary source emissions are

estimated to contribute 0.26 μ g/m 3 to the design day concentration. Stationary point sources would be expected to contribute a similar amount of PM 10 annual design value 2006.

Stationary sources are not expected to increase in future years for the same reasons discussed for the 24- hour standard: 1) current trends for this source category, which show a sli ght decrease in emissions from 1994 to 1998; 2) the fact that BACT controls are required for sources which produce more than two tons; 3) Lowest Achievable Emission Reductions (LAER) are Stationary Sources

Contribute Less than

One μ g/m 3 to the Annual Average

Stationary Source

Emissions in the

Nonattainment Area

Not Projected To

Increase4-116 required for all major sources which have been constructed or modified after September 26, 1996.

Residential firewood emissions, residential natural gas emissions, structural/vehicle/ wildfires, and charbroiling/ meat cooking, are projected to increase in proportion to the projected population growth as detailed in Table E-1 of Appendix E. Of the four emission sources projected to increase in proportion wit h the projected population growth, only one contributes more than 0.05 μ g/m 3 to the annual design value on a valley-wide basis. Charbroiling and meat cooking contribute 0.16 μ g/m 3 to the annual design value. In 2001 and 2006 charbroiling and meat cooking will contribute 0.19 μ g/m 3 and 0.32

μ g/m 3 respectively to the annual design values. New emissions from the larger sources within this category are subject to BACT requirements under Section 12, ensuring that this source category will not exceed the de

minimis source threshold in the 2001 or 2006 attainment

years.

The residential firewood com bustion source category is also subject to non-federal controls. This source category is projected to increase in proportion to population growth, but onl y contributes 0.02 μg/m 3 to the 1998 base year annual design value. This small source category is subject to the requirements of Clark County Ordinance1249, City of Las Vegas Ordinance 3538, City of North Las V egas Ordinance 1020, and City

of Henderson Ordinance 1997. These ordinances restrict new fireplaces to U. S. EPA Certified Phase II wood burning stoves or cl eaner alternative non-wood burning devices such as gas logs. Even in the face of potential cost increases fo r alternative home heating fuels, these control measures will limit emissions from this source category to levels that are far below the de

minimis source threshold.

4.6.2.3 Nonroad Mobile
The de minimis source categories within the nonroad mobile source category grouping are projected to remain relatively constant, grow in proportion with population growth, or grow in proportion to aviation activity as detailed in Tabl e E-1 of Appendix E. Nellis

Air Force Base emissions will remain constant. Of Residential Firewood

Emissions Not Expected To Become Significant

Construction and Mining Equipment

Largest Nonroad

Mobile Contributor to

PM 10 Emissions Other than Airports4-117 these source categories, the highest emissions are generated from construction and mining equipment and McCarran International Airport. Construction and mining equipment is project ed to grow in proportion to population growth and contributes 0.08 μg/m 3 to the 1998 annual base year, 0.09 μ g/m 3 to the 2001 annual design value, and 0.15 μ g/m 3 to the 2006 annual design value. Actual use of construction equipment is likely to decline in proportion with the declining growth rate. Emissions from McCarran International Airport contribute 0.05 μg/m 3 to the 1998 base year annual design value. These emissi ons will decline in future years due to aircraft gate electrification and use of newer, lower-emission aircraft.

4.6.2.4 Onroad Mobile

Onroad mobile de minimis sour ces include vehicular tire

wear and vehicular brake w ear. These contribute 0.02 μg/m 3 , and 0.03 μg/m 3 respectively to the 1998 base year annual design value. Projected increases in

vehicle miles traveled are shown for each road category in Table E-14 of Appendix E. These emission factors were generated using the M obile5b and Part5 models. These models show a slight increase in emissions from the tire wear and brake wear categories in future years, contributing 0.02 μ g/m 3 and 0.03 μ g/m 3 in 2001 and

0.04 μ g/m 3 and 0.06 μ g/m 3 in 2006.

4.6.3 Contingency Measures

Clark County Health District Board of Health adopted Resolution #03-00 on July 27, 2000 committing the Clark County Health District to evaluating the following candidate contingency measures for an assessment of suitability:

• Reduce the site-specific dust mitigation plan requirements for construction activities from ten acres to five acres;

• Require paving/stabilization of all unpaved roads with average daily traffic (ADT) equal to or exceeding 100 trips;

• Provide for at least two additional field enforcement officers above and beyond those

staff increases committed to in the State Implementation Plan; Contingency Measures

Have Been Identified by the Clark County

Health District Board

of Health4-118 • Increase minimum penalties for violations or Air Quality Regulations for fugitive dust; and

• Reduce the size threshold for requiring a dust control monitor (coordinator) at construction sites.

The entire set of contingency measures provided in

Section 4.6.3 will be automatica lly implemented if Clark County fails to meet t he projected 2003 emissions

reduction milestone. The emissions reduction benefit form these measures is 1, 373 tons (Appendix B), which

exceeds the 19.07 TPY emi ssion reduction increment.

4.7 CLARK COUNTY AI R QUALITY PROGRAMS

4.7.1 Clark County Educational Programs

4.7.1.1 Dust Control Class The Air Quality Division (AQD) conducts a Dust Control Class for permit compliance education and public

education. The class was in itiated in 1997 and initially used as a remedial or corrective requirement for violators of the Section 41 fugitive dust regulation.

In early 1998, the scope of the class was expanded to include a more thorough discussion of preventative measures. The requirement to complete the Dust

Control Class was extended to include the on-site superintendents or construc tion foremen for each new dust control permit issued. Interested members of the public have also attended the class. Those completing the class successfully receive a Certificate of Training and a photo-identification att endance card. The Dust Control Class is instructed by AQD Enforcement Officers and by contract instructors.

The class has been presented on numerous occasions to large employee groups of construction contracting companies, public utilities, and public agencies. When presented in this manner, the class discussion is modified to focus on the specific activities of the

company or group.

The AQD is in the process of shifting the focus of the

dust control class to Sect ion 94 of the Air Quality Regulations and the Secti on 94 Handbook. Special Dust Control Class Required To Obtain a

Dust Control Permit4-119 classes are being conducted to familiarize the construction industry with these new requirements.

4.7.1.2 Small Business Assistance Program
The AQD has contracted with t he University of Nevada, Reno Business Education Program to work with small businesses to explain AQD Air Quality Regulations and foster compliance.

4.7.1.3 Clark County C onservation District Education Program The AQD has contracted with the Clark County

Conservation District of S outhern Nevada to develop an

informational brochure that has been mailed to property owners who may be impacted by Section 90 requirements.

The AQD is currently asse ssing the feasibility of

additional roles for the Conservation District. These might include acting as adv isors to property owners on how to avoid receiving a co rrective action order and/or how to best respond to a corrective action order.

4.7.1.4 Construction I ndustry Training Programs Some of the building trade associations in the Las Vegas Valley have indicated that they will be providing training materials and/or cl asses to their members on

Section 94 and the Section 94 Handbook. These efforts are being developed on a voluntary basis by the industry in cooperat ion with the AQD.

4.7.1.5 Environmental Monitoring for Public Access and Community Tracking (EMPACT) Project The Las Vegas Valley EM PACT Website provides public access to time-rel evant environmental data including air quality, water quality, and meteorological information. Hourly updates from the AQD monitoring

network are available for a ll recorded levels of CO,

PM 10 , and ozone, as well as site-specific meteorological

data. Relevant health information related to the levels of pollution is also displayed in a format that is easily

understood.

The Las Vegas Valley EMPACT Website was developed with funding assist ance from the U. S. EPA EMPACT Funded by

U. S. EPA4-120 EMPACT program. The grant was awarded on a joint Nevada application by t he CCDCP, the City of Las Vegas, and the National Weat her Service. The CCDCP served as project coordinator for the website development, with funding provided to its project partners that included the AQD; the Conservation District of Southern Nevada; the University of Nevada, Las Vegas; and the Desert Res earch Institute.

4.7.1.6 Visibility Assessment and Time-Relevant Reporting This ongoing study is funded via an EMPACT Grant

from U. S. EPA and a grant from the Department of Motor Vehicles. This study provides time-relevant visibility data which can be accessed by the public via the interne t. The study report will characterize visibility in the Las Vegas Valley in regards to spatial, diurnal, weekday/weekend, and seasonal patterns. An assessment of sources contributing to

urban haze will be conducted as part of the study. Work will be coordinated with the SNAQS (See Section 4.7.2.1).

4.7.1.7 Dust Control Pr oduct and Equipment Trade

Shows Dust control product applicat ors, dust control product manufacturers, equipment manu facturers, building trade associations, and UNLV have indicated an interest in participating in dust control products and equipment trade show. The SCAQMD, San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD), and Mojave Desert AQMD have all successfully co-sponsored air pollution control product and equipment shows that were focused on different target groups.

The SCAQMD event was focused primarily on fugitive dust sources and included equip ment such as street sweepers and dust suppressant products. The SJVUAPCD co-sponsored thr ee events that were targeted primarily at th e agricultural industry and emphasized dust suppressant products. The Mojave Desert AQMD sponsored two shows that were more general in scope and targeted all types of air pollution control equipment and products. Dust Suppressant

Product Shows

Provide a Great Deal

of Information in One

Place4-121 Clark County will explore the feasibility of organizing and co-sponsoring a dust control product and equipment show in the Las Vegas Valley. The targeted

audience for the event would be the construction industry, public works agenc ies, and members of the general public.

4.7.2 Clark County Air Quality Research

4.7.2.1 Southern Nevada Air Quality Study (SNAQS) This study is current ly ongoing and focuses on measurement of primary par ticulate matter emissions

from motor vehicle exhaus t using LIDAR technology. Development of a GIS-based transportation model for the Las Vegas Valley and determining the frequency and magnitude of PM 2.5 transported into the Las Vegas Valley are components of the study. This study has been funded by the Federal Transit Administration.

4.7.2.2 Quantification of Ve hicular Emissions in the Las Vegas Valley Air Basin and Impacts on Air Quality This ongoing study is coor dinated with the SNAQS and is funded by the Nevada Depar tment of Motor Vehicles under the sponsorship of t he CCDCP. The focus of the study is development of a vehicle registration

information data base that is linked to emission measurements conducted as part of the SNAQS. This

data base will allow researchers to draw conclusions on the profiles of high-emitti ng vehicles, their geographic concentrations, the effectiv eness of the current smog check program, and to develop effective control strategies for reducing emi ssions from on-road gasoline

and diesel vehicles.

4.7.2.3 Chemical Ch aracterization of PM 2.5 in the Las Vegas Valley This ongoing study is coor dinated with the SNAQS and is funded by the Nevada Depar tment of Motor Vehicles under the sponsorship of t he CCDCP. The objectives of this study are characterization of the chemical composition of PM 2.5 in the Las Vegas Valley, estimation of the contribution of major source types to PM 2.5 concentrations and urban haze, the contributions of Continuing Research in Clark County4-122 transported constituents to PM 2.5 concentrations and urban haze, and the fraction of dust in PM 2.5 and PM 10 particulate concentrations. PM 2.5 samples will be taken at an urban and background site every third day for a one-year period. PM 10 samples will be taken every sixth day from a co-located PM 10 sampler at the urban site.

4.8 CLARK COUNTY AIR QUALITY SIP

COMMITMENTS

4.8.1 Commitment For Addi tional Staffing Levels

and Enhanced Enforcement Efforts

The AQD currently employs one enforcement supervisor, seven enforcem ent officers, one senior administrative clerk, one adm inistrative clerk, and one administrative secretary to enforce former Section 17 (Dust Control Permit for Construction) and Section 41 (Fugitive Dust). The AQ D has committed to hiring 15 additional staff to implement and enforce Sections 90, 91, 92, 93, and 94 with Resolu tion 02-00, dated July 27,

2000. 41 A new compliance team, titled Dust Mitigation and Prevention (DMAP), has been formed and will have ten new positions to focus on Sections 90, 91, 92, and 93 of the Air Quality Regulat ions. These positions will include a supervisor, cleric al, secretarial support, field enforcement, and one half-time attorney. An additional five new staff members will be hired to augment the existing construction activi ty program, as the newly adopted Section 94 supplem ents and strengthens the existing Sections 17 and 41 of the Air Quality Regulations. The five new positions for the construction program will include one person to handle additional construction permit processing, an additional clerical position, and three additiona l enforcement officers.

Costs incurred for the additional personnel and equipment (but not includi ng phones, computers, and

certain administrative cost s) are estimated to be $780,000 for the first year. Targeted funding sources are a dust control permit fee increase of $15 per acre (from $90 per acre to $105), redirecting funding from the

PM 10 Emission Control Research Account, and

increased funding from the Clark County general fund. The dust control permit fee was approved by the

41 See Appendix H Additional

Enforcement Staff Will

Be Hired

An Increase in Dust

Control Permit Fees Will Help Defray the

Costs of Additional

Staff4-123 Clark County Health District Board of Health on December 14, 2000. The CC HD is currently seeking office space for the new staff positions. Ramp-up of additional staff will occur during 2001, and all new positions will be filled by December 31, 2001. The

control measure effectiveness values utilized in this SIP are predicated on this schedule.

Violations of the Air Qua lity Regulations are heard by hearing officers who can make findings of violation and assess penalties. The AQD currently has five Board of Health-appointed hearing offi cers. Implementation of the new regulations in c onjunction with these enhanced enforcement efforts may resu lt in the need for additional hearing officers.

The AQD will identify and prioriti ze areas for inspection. The initial focus areas for inspection will be areas of Hydrographic Basin 212 characterized as having a high degree of soil disturbance.

4.8.2 Clark County Research Commitments

4.8.2.1 Participation in Funding Dust Suppressant

Multi-Media Studies Clark County Health District will participate in funding and coordination of research to determine the potential

for multi-media adverse envir onmental impacts from the long-term use of dust suppressant products. UNLV has recently obtained funding from local agencies for conducting a field study to evaluate potential long-term water quality impacts from the use of several classes of dust suppressant products. The study will evaluate impacts to both surface wate r runoff from treated areas and water that has percolated through a treated area. The AQD has provided partial funding for this study and
AQD and CCDCP staff ar e assisting UNLV in coordinating this work with re search planned by the

U. S. EPA. The results of the study are anticipated to

be available before the end of 2003.

4.8.2.2 Commitment to Conduct a PM 10 Saturation Study Clark County Department of Comprehensive Planning

will conduct a PM 10 saturation study that will begin in Dust Suppressants

and Their Effects Will

Be Studied4-124 2004 and be completed by the 2006 RFP Plan deadline. The focus of the study will be on neighborhood impacts of major sources, particu late concentrations in geographic locations not well covered by the current monitoring network due to growth within the valley, and inter-basin intra-basin transport during high wind events. The study will be conducted in later years to measure the impacts of growth in futu re years. In addition to the primary objectives of the study, the results will be

utilized in future evaluations of the National Ambient Monitoring Network (NAMS), State and Local Air Quality Monitoring Network (SLAMS), and Special Purpose Location (SPL) monitoring network.

4.8.2.3 Commitment to Develop An Improved Inventory of Unpaved Roads Clark County Department of Comprehensive Planning will develop an improved in ventory of unpaved roads. The inventory for publicly maintained roads will be developed by Clark County Public Works, City of North Las Vegas Public Works, City of Las Vegas Public Works, and City of Henderson Public Works departments and will be completed by the first quarter of 2002. The inventory of unpaved private roads will be completed by CCDCP using either satellite data or aerial photography by March of 2003.

4.8.2.4 Commitment to Develop An Improved Disturbed Vacant Land and Construction Inventory Clark County Department of Comprehensive Planning will pursue development of an improved inventory of

disturbed vacant land and construction activities. The vacant land inventory will be developed using satellite data and ground truthing. It will be completed by June of 2003. The construction activities inventory will be developed using the AQD dus t permitting data base, the Clark County’s GIS system and aerial photographs. The construction inventory update will be completed by

the end of 2002.

4.8.2.5 Commitment to D evelop Improved Emission

Factors for Native Desert and Disturbed Areas

The emission factors for nat ive desert used in the PM 10 plan were developed by UNLV based on data developed with the UNLV wi nd tunnel. When these Commitments To Improve Emission

Inventories4-125 test were conducted, the U. S. EPA test for soil surface characterization had not been developed. Because

both undisturbed native deser t and disturbed areas account for a major part of the PM 10 emissions that are generated during high wind conditions, a refinement of

the emission factors for thes e sources is warranted. Clark County Department of Comprehensive Planning anticipates moving forward with additional studies to develop refined emission factors in 2003, with completion of the studies expected by the end of 2005.

4.8.2.6 Commitment to Tr ack Silt Loadings on Paved

Roads Clark County Department of Comprehensive Planning

will conduct additional measurement s of silt loadings on paved roads in order to update the paved roads emission inventory and eval uate the effectiveness of

control measures for reduc ing silt loading on paved roads. Silt loading meas urements will begin in the fourth quarter of 2001 and be conducted quarterly though June of 2006.

4.8.2.7 Commitment to Establish Test Methods for

Section 94 If an acceptable test me thod has not been developed and adopted into Section 94 by September 1, 2001, Clark County will fund additional research up to $100,000 to develop an acceptable test method. It is Clark County’s intention that a contractor will be selected by November 1, 2001. If a test method that is acceptable to U. S. EPA under its BACM and enforceability criteria has not been incorporated into Section 94 by November 1, 2002, the opacity test method for unpaved roads in Section 91 will be presented to the governi ng board for adoption in

December of 2002 for all non- process, intermittent construction site fugitive dust generating activities.

4.8.2.8 Commitment to U pdate Emission Inventories Clark County will revise the entire PM 10 emission

inventories for the attainm ent year in 2003 and 2006 to

coincide with the Reasonable Further Progress reports.

If the emission inventories are significantly different than in this SIP, particularly if t he differences would affect the attainment demonstration, the SIP will be adjusted to Commitment to

Research Development of a

Better Construction

Activities Test Method4-126 reflect the revised PM 10 emission inventorie s. If the SIP inventory requires adjustment, it will be resubmitted for approval to U. S. EPA wit h the Reasonable Further Progress/milestone reports that include revising conformity budgets and re-evaluation of control measures if necessary. The existing approved SIP and conformity budgets will remain in place until such time as a new SIP is approved.

4.8.2.9 Commitment to Revise Air Quality Regulations The following proposed language for revision to the Air Quality Regulations will move forward in the rule development and adoption process, with rule revisions to be brought to the Clark C ounty Health District Board of Health for approval at the regularly scheduled meeting in August of 2001.

Section 90.2.1.3 – Dust Mitigation Plan Required :

Owners A ND /O R O PERATORS of O PEN A REAS A ND
V ACANT L OTS having a cumulative area of 10,000 acres or greater must submit a dust mitigation plan to the Air Quality Division for approval by January 1, 2002 in a format prescribed by the

C ONTROL O FFICER

.

Section 92.2.1.1 Revised Section:

No U NPAVED P ARKING L OTS may be constructed after the adoption of this Subsection except as provided in Subsection 92.2.1.1 (a) and (b)

below:

(a) The requirements of Subsection 92.2.1.1 shall not be applicable to parking lots for rural public facilities such as trailheads, campgrounds, and similar facilities where paved parking lots would conflict with the rural nature of these facilities; and

(b) The unpaved parking lot is

stabilized in accordance with Subsection 92.2.1.2 (b) through (d) Revisions to Air Quality Regulations Moving

Forward in The Rule

Process