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WRAP Fugitive Dust Emission Summary and Evaluation (AoH Phase II/TSS Task 7b). ENVIRON International Corporation 15 November 2005 Tempe, AZ. Outline. Project Objectives Fugitive Dust Source Categories Emission Estimation Methodologies 2002 Annual County-level Summaries
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WRAP Fugitive Dust EmissionSummary and Evaluation(AoH Phase II/TSS Task 7b) ENVIRON International Corporation 15 November 2005 Tempe, AZ
Outline • Project Objectives • Fugitive Dust Source Categories • Emission Estimation Methodologies • 2002 Annual County-level Summaries • 2002 Annual Gridded Summaries • PM2.5/PM10 Ratios • Next Steps
Project Objectives • Summarize all fugitive dust emission sources • Evaluate dust emissions for reasonableness and consistency • Review estimation methodologies (AP-42, State/local studies, regional models, etc..) • Review fine fraction (PM10/PM2.5) • Develop SCC-level summaries: • County-level • Model-ready, gridded • Develop summaries by geographic region • Consider 2002 and 2018 EIs
Fugitive Dust Source Categories • Agricultural Dust • Harvesting • Tilling • Transport • Feedlots • Construction Dust • Mining/Quarrying • Road Construction • Residential • Industrial/Commercial/Institutional • Road Dust • Paved • Unpaved • Windblown Dust
Estimation Methodologies • Agricultural Tilling • 2002 NEI grown from 1998 • Growth factors vary by tilling type (0.77 – 1.16) • Activity is acres tilled by type and crop (from CTIC) • EF = 4.8*k*s0.6*p • k=particle size multiplier (PM10 = 0.21; PM2.5 = 0.042) • S = silt content (USDA data; varies by soil type) • P = # of passes/tilling per year (varies by crop) • E = EF * A
Estimation Methodologies • Construction – Residential • Emissions are function of acres disturbed and volume of soil excavated (varies by type of structure) • Activity data (housing starts by structure type) from Dept. of Commerce • Emission factors vary by structure type and duration of construction (0.011 tons PM10/acre-month – 0.11 tons PM10/acre-month) • Adjustments applied for soil moisture, silt content and control efficiency
Estimation Methodologies • Construction – Non-Residential • Emissions are function of acres disturbed • Activity data (value of construction in $MM, allocated from national to county based on employment statistics) from Dept. of Commerce • Number of acres disturbed estimated as 1.55 acres/$MM applied to county-level construction valuation data • Emission factor = 0.19 tons/acre/month (assumed 11 month construction duration) • Adjustments applied for soil moisture, silt content and control efficiency
Estimation Methodologies • Road Construction • Emissions are function of acres disturbed; developed from FHWA data • State-level new miles of road construction from 2002 FHWA state expenditure data by road type • Converted to $/mile using NCDOT conversion data; converted to acres disturbed/mile by road type • State data allocated to county based on residential building starts • Emission factor = 0.42 tons/acre/month; assumed 12 month duration • Adjustments applied for soil moisture, silt content and control efficiency
Estimation Methodologies • Paved Road Dust • Uncontrolled emissions estimated at state level by roadway class and month • Calculated as State/Roadway class VMT * TAF * EF • Spatially allocated to counties based using VMT surrogate • Controls applied to Non-Attainment counties • EF = [k*(sL/2)0.65 *(W/3)1.5-C]*[1-P/(4*N)] • k= particle size multiplier (PM10 = 7.3;PM2.5 = 1.8) • sL = silt loading • W= avg. vehicle weight • C = EF for 1980 fleet • N= # days in month • P= # days with precip. > 0.01 in • Annual VMT data from FHWA Statistics • County emissions = State Emissions * (VMTcounty/VMTState) • Assumed control measure: Vacuum sweeping twice/month; 79% control efficiency.; Rule penetration varies by roadway class and NA status; 100% Rule Effectiveness
Estimation Methodologies • Unpaved Road Dust • Uncontrolled emissions estimated at state level by roadway class and month • Calculated as State/Roadway class VMT * TAF * EF • Spatially allocated to counties based using 1990 rural population surrogate • Controls applied to Non-Attainment counties • EF = [k*(s/12)a *(SPD/30)b]/(M/0.5)c-C • k= particle size multiplier (PM10 = 0.27;PM2.5 = 1.8) • s = silt loading • SPD = mean vehicle speed • M = moisture content • C = EF for 1980 fleet • a,b,c = empirical constants • EF adjusted for precip: Efcorr= EF * [(D-p)/D)] • D = # days in month • P = # days with precip > 0.01 in.
Estimation Methodologies • Unpaved Road Dust (continued) • Annual VMT data from FHWA Statistics • Separate estimates for county and non-county roadways • County-maintained VMT by road type and ADTV • State/Federal-maintained VMT by arterial classification; county-maintained VMT used • Annual VMT estimates allocated seasonally and monthly • County emissions = State Emissions * (Rural Pop.county/Rural Pop.State) • Assumed control measures vary by Non-Attainment classification (paving and/or chemical stabilization). Control efficiency, rule penetration and rule effectiveness vary
Estimation Methodologies • Windblown Dust • WRAP Phase II WB Dust Model • 2000 Landuse/Landcover data • BELD3 county-level crop percentages • STATSGO Soils data • 2002 MM5 Meteorology (36- and 12-km) • Latest Transport Fractions (EPA, 2005) • PMC/PMF = 0.9/0.1
RPO-Specific Revisions/Enhancements • WRAP • Road Dust – Developed by ENVIRON. • CA emissions interpolated from previous EI development • Unpaved VMT based on NET96 updated with state survey results • VMT data adjusted based on Clark Co. ADTV revisions factor • Silt loading from IL State Water Survey • Precipitation data from NCDC • Applicable control measures from State survey results • Agricultural Dust - Developed by ERG based on 2002 draft NEI (gap-filled by EPA/Pechan). Additional state submissions included as part of WRAP EI Update process. • Construction Dust - 2002 NEI estimates submitted by States
RPO-Specific Revisions/Enhancements • CENRAP • Agricultural Dust – Developed by STI based on local activity data, county-level silt loading and tilling practices, monthly allocation by state. Includes some livestock feedlot dust emissions • Construction and Road Dust from 2002 NEI • VISTAS • 2002 NEI State submissions for all sources • MWRPO • Agricultural and Construction Dust (IL & IN only) - Based on 2002 State CERR data • Road Dust – WRAP 2002 inventory data • All Fugitive dust emissions dramatically reduce through application of transport fractions (90%-97%). Based on monitoring data analyzed by LADCO • MANE-VU • 2002 NEI for all dust sources
Proposed Revisions to Fine Fraction RatiosUsed for AP-42 Fugitive Dust Emission Factors