Appendix A Air Quality Conformity Analysis

Transcription

1 Appendix A Air Quality Conformity Analysis

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3 Atkins North America, Inc Sky Park Court, Suite 200 San Diego, California Telephone: Fax: June 2, 2011 Mr. Chris Jacobs City of La Mesa 8130 Allison Avenue La Mesa, California Subject: Upgrade Project Air Quality Conformity Analysis Alvarado Trunk Sewer Project City of La Mesa, San Diego County, California Dear Mr. Jacobs: This letter report provides an air quality conformity analysis for the Alvarado Trunk Sewer Upgrade Project (project) in compliance with CEQA-Plus requirements, which requires conformance with the Federal Clean Air Act. BACKGROUND The State Revolving Fund (SRF) Loan Program is partially funded by the U.S. Environmental Protection Agency (US EPA) and subject to federal environmental regulations, including the General Conformity Rule for the Clean Air Act. Clean Air Act general conformity requirements apply to projects in areas either not meeting federal national ambient air quality standards or that are subject to a maintenance plan. An analysis is required for each criteria pollutant for which an area is considered as being in federal non-attainment or maintenance. If project emissions are below the de minimis level and less than 10 percent of the emissions inventory for the pollutants for which the area is in non-attainment, then further general conformity analysis is not required. If project emissions are above the de minimis level, then a conformity determination for the project must be made. PROJECT DESCRIPTION The Alvarado Trunk Sewer Upgrade Project proposes to replace a segment of the existing sewer trunk main located adjacent to the Alvarado Creek channel in the City of La Mesa, California. The purpose of the project is to reduce infiltration and inflow of storm water into the existing sewer trunk main. Additionally, the project would upgrade the capacity of the pipelines consistent with the City s Sewer Master Plan, which identifies these pipeline segments as being under capacity and requiring upsizing to handle existing and future flows. The existing sewer main is a 12-inch vitrified clay pipe (VCP). The existing sewer main is located within the Alvarado Creek channel for a portion of its length, within the property of a multi-family residential development for a portion of its length, and ends with a segment that crosses the MTS San Diego Trolley tracks. The project alignment runs in an west-east direction from just south of the east side of the

4 Mr. Chris Jacobs June 2, 2011 Page 2 of 8 American Automobile Association (AAA) Building parking structure on Bus Court to the east side of a parking lot serving a residential apartment complex off Amaya Court, adjacent to the parking lot for the trolley station on Amaya Court. The project proposes to install an 18-inch high-density polyethylene (HDPE) welded pipe that would be located in the northern slope of the Alvarado Creek channel. In the western portion of the alignment, the channel is natural and open. In this portion the replacement pipeline would be offset from the existing pipeline alignment. For the portion of the sewer alignment where the channel is enclosed in a box culvert (eastern portion), the replacement sewer alignment would either be constructed using the open trench method and located to the south of the existing alignment, or be constructed using the pipe bursting method and be located in the same alignment as the existing pipeline. The project proposes to install the entire replacement pipeline via a combination of open trench, pipe bursting, and jack and bore methods in the slope of the Alvarado Creek channel. The portions of the proposed alignment that would be installed using the jack and bore method include the areas located within Caltrans (SR-125) and MTS right-of-way. The jack and bore method would also be used in the areas where the proposed pipeline alignment is near an existing gas line in order to protect the gas line in place. For the purposes of this analysis, for any portions of the pipeline where multiple construction methods are being considered, it is assumed that the open trench method would be employed because this method would result in greater physical environmental impacts than any of the other construction methods (pipe reaming, pipe bursting, or jack and bore). The open trench method of construction would involve the most ground disturbance and heavy equipment because it would require the excavation of a trench along the entire portion of pipeline to be installed using this method. Trenchless installation (jack and bore method) would require excavation of pits at both ends of the segment only. Pipe reaming and pipe bursting would entail installation of the new pipeline by breaking the old pipeline using the existing pipe s lines and grades. It would not require pits or trenches. Therefore, the open trench construction method represents the worst-case scenario. Three potential replacement alignments have been identified; however, only one would be implemented. The three alignments vary slightly in linear feet. Alternative alignment 1 would install 2,365 linear feet of sewer trunk main, Alternative 2 would install 2,445 linear feet, and Alternative 3 would install 2,420 linear feet. For the purposes of this analysis, Alternative 2 is assumed to be the proposed project because it would require the greatest amount of open trench construction and represents the worst-case scenario. The replacement alignment for all three alternatives would be the same from the west endpoint of the project near to the eastern end of the project area near existing MH A The western endpoint of all three alternatives would be located in the Alvarado Creek channel south of the AAA building parking lot along Fletcher Parkway at Bus Court. The alignment of all three alternatives would then extend easterly to a residential apartment complex off Amaya Court, adjacent to the Amaya Trolley Station, near the intersection of Fletcher Parkway and Amaya Drive. From here, all three alternative alignments would extend south, across the MTS right-of-way, which contains light rail (San Diego Trolley) tracks. At this point, the three alignments would separate into different directions. The alternative alignments vary near the eastern end north of the light rail tracks between existing manhole (MH) A and proposed new MH Y. Alternative 2 would extend directly south from MH

5 Mr. Chris Jacobs June 2, 2011 Page 3 of 8 A to MH Y. Alternative 2 would also include a new pipeline segment from MH A to MH Y. All three alternative alignments would extend south from MH Y into and through the parking area of an existing multi-family residential development to Campina Drive. The majority of the proposed alignment parallels the MTS right-of-way, with the exception of the segments between MH A and MH Y, which cross the right-of-way. Three existing manholes would be abandoned and three would be replaced as part of the proposed project. The project also proposes the installation of 11 new manholes along the project alignment. Six existing manholes would be raised within the creek channel to prevent inflow of water from the channel into the sewer pipeline during rain events. The proposed project also includes the point repair of an existing pipeline segment located in the paved area of the cul-de-sac on Campina Drive, just south of the eastern end of the proposed alignment. The repair would entail digging a pit to repair a small area of an existing pipeline, then filling in the pit and paving the roadway to match existing conditions. REGULATORY SETTING The Clean Air Act of 1970 required the EPA to establish National Ambient Air Quality Standards (NAAQS) with states retaining the option to adopt more stringent standards or to include other specific pollutants. The 1990 CAA Amendments require that each state have an air pollution control plan called the State Implementation Plan (SIP). The SIP includes strategies and control measures to attain the NAAQS by deadlines established by the CAA. The CAA Amendments dictate that states containing areas violating the NAAQS revise their SIPs to include extra control measures to reduce air pollution. The US EPA reviews the SIPs to determine whether the plans would conform to the 1990 CAA Amendments and achieve the air quality goals. The US EPA has classified air basins (or portions thereof) as being in attainment, nonattainment, or unclassified for each criteria air pollutant, based on whether or not the NAAQS have been achieved. If an area is designated unclassified, it is because inadequate air quality data were available as a basis for a nonattainment or attainment designation. Table 1 lists the attainment status of San Diego County for the criteria pollutants. The US EPA classifies the San Diego Air Basin (SDAB) as in attainment for carbon monoxide (CO), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), lead, and fine particulates (under 2.5 microns or PM 2.5 ) with respect to federal air quality standards. The SDAB is currently in basic nonattainment for the federal 8-hour ozone standard. The Eight Hour Ozone Attainment Plan for San Diego County was prepared by the San Diego County Air Pollution Control District (SDAPCD or District) in 2007, which identifies control measures to reduce emissions of ozone precursors (VOCs and NOx) and complies with federal SIP requirements. The state of California has established standards for criteria pollutants that are generally stricter than federal standards. As shown in Table 1, the SDAB is currently in nonattainment status for the state standards for ozone, respirable particulate matter (PM 10 ), and fine particulate matter (PM 2.5 ).

6 Mr. Chris Jacobs June 2, 2011 Page 4 of 8 Table 1. San Diego County Air Basin Attainment Status Pollutant Averaging Time California Standards Federal Standards Ozone (O 3 ) Respirable Particulate Matter (PM 10 ) Fine Particulate Matter (PM 2.5) Carbon Monoxide (CO) Nitrogen Dioxide (NO 2 ) Lead Sulfur Dioxide (SO 2 ) 1 Hour No Federal Standard Nonattainment 8 Hour Basic Nonattainment Annual Arithmetic Mean No Federal Standard Nonattainment 24 Hour Unclassified (1) Annual Arithmetic Mean Nonattainment 24 Hour No State Standard 8 Hour 1 Hour Attainment Attainment Maintenance Area (2) Annual Arithmetic Mean No State Standard Attainment 1 Hour Attainment No Federal Standard Calendar Quarter No State Standard Attainment 30 Day Average Attainment No Federal Standard Annual Arithmetic Mean No State Standard Attainment 24 Hour Attainment Attainment 1 Hour Attainment No Federal Standard Sulfates 24 Hour Attainment No Federal Standard Hydrogen Sulfide 1 Hour Unclassified No Federal Standard Visibility Reducing Particulates (1) 8 Hour (10:00 a.m. to 6:00 p.m., PST) Unclassified No Federal Standard Unclassified; indicates data are not sufficient for determining attainment or nonattainment. (2) Maintenance Area (defined by U.S. Department of Transportation) is any geographic region of the United States previously designated nonattainment pursuant to the CAA Amendments of 1990 and subsequently re-designated to attainment subject to the requirement to develop a maintenance plan under section 175A of the CAA, as amended. Source: CARB, Area Designation Maps. Data reflects status as of May STANDARDS OF SIGNIFICANCE Federal De Minimis Levels With regard to conformity of Federal standards, the Code of Federal Regulations (CFR) provides guidance to document Clean Air Act Conformity Determination requirements. 40 CFR Part (b)(2) defines de minimis levels, that is, the minimum thresholds for which a conformity determination must be performed for criteria pollutants, based on the attainment status of the pollutant in the air basin. Table 2 includes the federal de minimis levels for the criteria pollutants for which the SDAB is in either nonattainment or maintenance for the NAAQS. The SDAB is in attainment or designated as unclassified for PM 10, PM 2.5, SO 2, NO 2, and lead. As a result, no federal conformity determination is required for these pollutants.

7 Mr. Chris Jacobs June 2, 2011 Page 5 of 8 Table 2. Federal De Minimis Levels Pollutant Volatile Organic Compounds (VOC) Nitrogen Oxides (NOx) Carbon Monoxide Source: 40 CFR Part (b)(2). Threshold 50 tons/year 50 tons/year 100 tons/year SDAPCD The SDAPCD does not provide quantitative thresholds for determining the significance of construction or mobile source-related projects. However, the District does specify Air Quality Impact Analysis (AQIA) trigger levels for new or modified stationary sources (APCD Rules 20.2 and 20.3) If these incremental levels are exceeded, an AQIA must be performed. Although these trigger levels do not generally apply to general land development projects, for comparative purposes these levels may be used to evaluate the increased emissions from these projects. The screening level thresholds can be used to demonstrate that a project s total emissions would not result in a significant impact to regional air quality. Because the AQIA screening thresholds do not include VOCs, the screening level for VOCs used in this analysis are from the South Coast Air Quality Management District (SCAQMD), which generally has stricter emissions thresholds than SDAPCD. For PM 2.5, the EPA Proposed Rule to Implement the Fine Particle National Ambient Air Quality Standards published in 2005, which quantifies significant emissions as 10 tons per year, will be used as the screening level threshold. The trigger thresholds listed in Table 3 below are used in this analysis to determine whether the project has the potential to violate regional air quality standards. Table 3. SDAPCD Air Pollutant Thresholds Pollutant Pounds Per Hour Pounds Per Day Tons Per Year Carbon monoxide (CO) Nitrogen Oxides (NOx) Respirable Particulate Matter (P M 10 ) Fine Particulate Matter (PM 2.5 ) (1) 10 (1) Oxides of Sulfur (SOx) Lead (Pb) Volatile Organic Compounds (VOC) (2) 13.7 (2) (1) EPA Proposed Rule to Implement the Fine Particle National Ambient Air Quality Standards published September (2) Based on VOC threshold from SCAQMD. Source: SDAPCD Rule 1501, 20.2 (d)(2), Table

8 Mr. Chris Jacobs June 2, 2011 Page 6 of 8 CONSTRUCTION IMPACTS Construction activities would result in temporary increases in air pollutant emissions. These emissions would be generated primarily from construction equipment exhaust, earth disturbance, and construction worker vehicle trips. Air pollutant emissions were estimated using the worst-case activity data and the emission factors included in the URBEMIS 2007 model, which takes into account the hours of operation, load factor and the emission factors for each piece of equipment. For detailed model assumptions, please see Attachment A. Construction would occur in three phases. Construction is expected to occur during the dry season from approximately July to October and would last approximately four months. Removal of any trees necessary for construction is expected to occur outside of the raptor breeding season (January 15 through July 15). Construction of the project would occur between the hours of 7:00 a.m. and 5:00 p.m., Monday through Friday. The only exception would be construction within the MTS right-of-way, which may occur at nighttime when trolley services are not operating as per MTS permit requirements. During Phase 1, vegetation would be cleared from the Alvarado Creek channel and banks in the area of the proposed improvements. Particulate (PM 10 and PM 2.5 ) emissions during construction depend on the size of the disturbance footprint. This phase would take approximately one month. A total of 0.53 acres would be graded to allow construction equipment to gain access to the proposed alignment and allow for trenching and boring operations to occur along the proposed alignment. A maximum of 0.03 acres would be graded per day, based on 20 workings days per month. The equipment list for this phase was assumed to include a backhoe, bulldozers, dump trucks, and a generator. Phase 2 of construction would last approximately 3 months and would include slope benching, trenching, pipeline installation, trench backfilling, and manhole installation, replacement, and raising. Phase 2 would be completed in segments between the proposed and existing manholes. As discussed above, this phase would be accomplished using combination of open trench, pipe bursting, pipe reaming and jack and bore methods. Alternative 2 represents the worst-case scenario for pipeline installation. This alternative would install 2,445 linear feet of pipeline. Approximately 614 feet of pipeline would be installed using the jack and bore method. It is assumed that the remaining 1,831 linear feet would be installed using open trench construction. Jack and bore construction would require seven pits to be excavated. These pits would be a maximum size of 375 square feet and 18 feet deep. Open trenches would be five feet wide and a maximum depth of 18 feet. The pit required for the point repair on Campina Drive would be the same size and the jack and bore pits. Based on these maximum dimensions, a total of 7,867 cubic yards of material would be excavated over three months, or a maximum of 131 cubic yards per day. Due to the large amount of cobbles and other material unsuitable for backfill within the project alignment, it is estimated that a total of 5,900 cubic yards of material would be removed and exported from the site over the three months and equal amounts of imported material would be necessary for a balanced grading approach. The equipment list for this phase was assumed to include a backhoe, bulldozers, dump trucks, concrete trucks, cement and mortar mixer, boring drill, a concrete saw, a paver, and a generator. Phase 3 would include restoring the channel slope to a 2:1 slope, revegetating the slope and the channel edge, and filling the abandoned existing sewer trunk main with slurry. The equipment list for this phase was assumed to include a backhoe, pump, cement and mortar mixer, and generator.

9 Mr. Chris Jacobs June 2, 2011 Page 7 of 8 The emissions from project construction are included in Table 4. The emissions are broken out into pounds per day for the San Diego regional comparison and tons per year for the federal de minimis comparison for each year of construction. Future construction emissions are estimated to gradually decrease as equipment complies with progressively stricter state and federally mandated emission requirements. As shown in Table 4, all emissions are well below the recommended federal and regional significance thresholds. Table 4. Estimated Construction Maximum Air Pollutant Emissions Phase Maximum Daily Emissions (pounds/day) VOC NOx CO SO x PM 10 PM 2.5 Phase I (1) Phase II Phase III SDAPCD Threshold Impact? No No No No No No Maximum Annual Emissions (tons/year) Phase I (1) < 0.1 < 0.1 Phase II Phase III < < 0.1 < 0.1 Federal Threshold Impact? No No No (1) Estimates of particulate emissions take into account application of soil stabilizers to inactive areas during grading in mandatory compliance with SDAPCD Rule 55. Source: URBEMIS 2007, version See Attachment A for model output. OPERATION EMISSIONS The project is a sewer and manhole upgrade project. Once installed, the system is passive and would not require regularly scheduled equipment operation or generate trips that could emit criteria pollutants. Thus, the operation of the sewer pipeline would not generate operational air pollutant emissions. SUMMARY Table 5 compares the estimated project emissions with the SDAB emissions inventory for VOC and NOx emissions (ozone precursors), based on the projections listed in the SDAPCD s 2009 Regional Air Quality Strategy for the year As shown, the project s maximum daily emissions are well below 10 percent of the 2010 emission level for both VOC and NOx. Therefore, the project emissions are below the de minimis level and less than 10 percent of the emissions inventory for the nonattainment area, and further general conformity analysis is not required. Pipeline and manhole replacement activities are a temporary source of adverse, but less than significant, air pollutant emissions.

10 Mr. Chris Jacobs June 2, 2011 Page 8 of 8 Table 5. San Diego Air Basin Emission Inventory Pollutant 2010 Emission Level 10 percent of 2010 Emission Level Project Emissions Exceed? VOC Emissions 160 tons/day 16 tons/day tons/day No NOx Emissions 182 tons/day 18 tons/day 0.06 tons/day No Source: SDAPCD, REFERENCES CARB Area Designation Maps. California Air Resources Board. Data reflects status as of May CFR Title 40: Protection of Environment. Part 93: Determining Conformity of Federal Actions to State or Federal Implementation Plans, Subsection 153. Code of Federal Regulations. Current as of July 16, SPAPCD Rule 1501, 20.2 (d)(2), Table Effective June SDAPCD Eight-Hour Ozone Attainment Plan for San Diego County. San Diego County Air Pollution Control District. May. SDAPCD Regional Air Quality Strategy Revision, San Diego County Air Pollution Control District. April 22. SWRCB State Water Resources Control Board Division of Financial Assistance. Environmental Review Process Guidelines for State Revolving Fund Load Applicants. State Water Resources Control Board. September. URBEMIS URBEMIS Version Copyright 2007 Rimpo and Associates. US EPA General Conformity De Minimis Levels. Last updated on May 6, If you have any questions regarding this analysis, please do not hesitate to call at (858) or at joanne.dramko@atkinsglobal.com. Sincerely, Joanne M. Dramko, AICP, GISP Senior Environmental Manager Attachment A: URBEMIS air quality model output

11 Page: 1 5/3/ :08:26 AM Urbemis 2007 Version Combined Summer Emissions Reports (Pounds/Day) File Name: C:\Documents and Settings\22242\Desktop\Alvarado\AQ\Alvarado urb924 Project Name: Alvarado Truck Sewer Upgrade Project Location: California State-wide On-Road Vehicle Emissions Based on: Version : Emfac2007 V2.3 Nov Off-Road Vehicle Emissions Based on: OFFROAD2007 Summary Report: CONSTRUCTION EMISSION ESTIMATES ROG NOx CO SO2 PM10 Dust PM10 Exhaust PM10 PM2.5 Dust PM2.5 Exhaust PM2.5 CO TOTALS (lbs/day unmitigated) 2011 TOTALS (lbs/day mitigated) , , Construction Unmitigated Detail Report: CONSTRUCTION EMISSION ESTIMATES Summer Pounds Per Day, Unmitigated ROG NOx CO SO2 PM10 Dust PM10 Exhaust PM10 PM2.5 Dust PM2.5 Exhaust PM2.5 CO2 Time Slice 7/1/2011-7/29/2011 Active Days: 21 Fine Grading 07/01/ /31/ Fine Grading Dust Fine Grading Off Road Diesel Fine Grading On Road Diesel Fine Grading Worker Trips Time Slice 8/1/ /31/2011 Active Days: 66 Mass Grading 08/01/ /31/2011 Mass Grading Dust Mass Grading Off Road Diesel Mass Grading On Road Diesel Mass Grading Worker Trips , , , , , ,

12 Page: 1 5/3/ :08:26 AM Trenching 08/01/ /31/ Trenching Off Road Diesel Trenching Worker Trips Time Slice 11/1/ /30/ Active Days: 22 Asphalt 11/01/ /30/ Paving Off-Gas Paving Off Road Diesel Paving On Road Diesel Paving Worker Trips , , , , , Phase Assumptions Phase: Fine Grading 7/1/2011-7/31/ Phase I Total Acres Disturbed: 0.53 Maximum Daily Acreage Disturbed: 0.03 Fugitive Dust Level of Detail: Default 20 lbs per acre-day On Road Truck Travel (VMT): 0 Off-Road Equipment: 1 Generator Sets (549 hp) operating at a 0.74 load factor for 8 hours per day 2 Off Highway Trucks (479 hp) operating at a 0.57 load factor for 8 hours per day 2 Rubber Tired Dozers (357 hp) operating at a 0.59 load factor for 6 hours per day 1 Tractors/Loaders/Backhoes (108 hp) operating at a 0.55 load factor for 7 hours per day Phase: Mass Grading 8/1/ /31/ Phase II - Used to estimate excavation emissions and import/export emissions. Equipment list is split between Mass Grading and Trenching Phase Total Acres Disturbed: 0.53 Maximum Daily Acreage Disturbed: 0.01 Fugitive Dust Level of Detail: Low Onsite Cut/Fill: 131 cubic yards/day; Offsite Cut/Fill: 0 cubic yards/day On Road Truck Travel (VMT): Off-Road Equipment: 1 Cement and Mortar Mixers (10 hp) operating at a 0.56 load factor for 8 hours per day 4 Off Highway Trucks (479 hp) operating at a 0.57 load factor for 8 hours per day 2 Rubber Tired Dozers (357 hp) operating at a 0.59 load factor for 6 hours per day

13 Page: 1 5/3/ :08:26 AM 1 Tractors/Loaders/Backhoes (108 hp) operating at a 0.55 load factor for 7 hours per day Phase: Trenching 8/1/ /31/ Phase II Off-Road Equipment: 1 Bore/Drill Rigs (291 hp) operating at a 0.75 load factor for 8 hours per day 1 Concrete/Industrial Saws (10 hp) operating at a 0.73 load factor for 8 hours per day 1 Generator Sets (549 hp) operating at a 0.74 load factor for 8 hours per day 1 Pavers (100 hp) operating at a 0.62 load factor for 8 hours per day Phase: Paving 11/1/ /30/ Phase III - Conservative because revegetation would be less equipment intensive Acres to be Paved: 0.53 Off-Road Equipment: 1 Cement and Mortar Mixers (10 hp) operating at a 0.56 load factor for 6 hours per day 1 Generator Sets (549 hp) operating at a 0.74 load factor for 8 hours per day 1 Pumps (53 hp) operating at a 0.74 load factor for 8 hours per day 1 Tractors/Loaders/Backhoes (108 hp) operating at a 0.55 load factor for 7 hours per day Construction Mitigated Detail Report: CONSTRUCTION EMISSION ESTIMATES Summer Pounds Per Day, Mitigated ROG NOx CO SO2 PM10 Dust Time Slice 7/1/2011-7/29/2011 Active Days: 21 Fine Grading 07/01/ /31/ Fine Grading Dust Fine Grading Off Road Diesel Fine Grading On Road Diesel Fine Grading Worker Trips Time Slice 8/1/ /31/2011 Active Days: 66 Mass Grading 08/01/ /31/2011 Mass Grading Dust Mass Grading Off Road Diesel Mass Grading On Road Diesel Mass Grading Worker Trips PM10 Exhaust PM10 PM2.5 Dust PM2.5 Exhaust PM2.5 CO , , , , , ,

14 Page: 1 5/3/ :08:26 AM Trenching 08/01/ /31/ Trenching Off Road Diesel Trenching Worker Trips Time Slice 11/1/ /30/ Active Days: 22 Asphalt 11/01/ /30/ Paving Off-Gas Paving Off Road Diesel Paving On Road Diesel Paving Worker Trips , , , , , Construction Related Mitigation Measures The following mitigation measures apply to Phase: Fine Grading 7/1/2011-7/31/ Phase I For Soil Stablizing Measures, the Apply soil stabilizers to inactive areas mitigation reduces emissions by: PM10: 84% PM25: 84%

15 Page: 1 5/3/ :08:41 AM Urbemis 2007 Version Combined Annual Emissions Reports (Tons/Year) File Name: C:\Documents and Settings\22242\Desktop\Alvarado\AQ\Alvarado urb924 Project Name: Alvarado Truck Sewer Upgrade Project Location: California State-wide On-Road Vehicle Emissions Based on: Version : Emfac2007 V2.3 Nov Off-Road Vehicle Emissions Based on: OFFROAD2007 Construction Unmitigated Detail Report: CONSTRUCTION EMISSION ESTIMATES Annual Tons Per Year, Unmitigated ROG NOx CO SO2 PM10 Dust PM10 Exhaust PM10 PM2.5 Dust PM2.5 Exhaust PM2.5 CO Fine Grading 07/01/ Fine Grading Dust Fine Grading Off Road Diesel Fine Grading On Road Diesel Fine Grading Worker Trips Mass Grading 08/01/ Mass Grading Dust Mass Grading Off Road Diesel Mass Grading On Road Diesel Mass Grading Worker Trips Trenching 08/01/ /31/ Trenching Off Road Diesel Trenching Worker Trips Asphalt 11/01/ /30/ Paving Off-Gas Paving Off Road Diesel Paving On Road Diesel Paving Worker Trips

16 Page: 1 5/3/ :08:41 AM Phase Assumptions Phase: Fine Grading 7/1/2011-7/31/ Phase I Total Acres Disturbed: 0.53 Maximum Daily Acreage Disturbed: 0.03 Fugitive Dust Level of Detail: Default 20 lbs per acre-day On Road Truck Travel (VMT): 0 Off-Road Equipment: 1 Generator Sets (549 hp) operating at a 0.74 load factor for 8 hours per day 2 Off Highway Trucks (479 hp) operating at a 0.57 load factor for 8 hours per day 2 Rubber Tired Dozers (357 hp) operating at a 0.59 load factor for 6 hours per day 1 Tractors/Loaders/Backhoes (108 hp) operating at a 0.55 load factor for 7 hours per day Phase: Mass Grading 8/1/ /31/ Phase II - Used to estimate excavation emissions and import/export emissions. Equipment list is split between Mass Total Acres Grading Disturbed: and Trenching 0.53 Phase Maximum Daily Acreage Disturbed: 0.01 Fugitive Dust Level of Detail: Low Onsite Cut/Fill: 131 cubic yards/day; Offsite Cut/Fill: 0 cubic yards/day On Road Truck Travel (VMT): Off-Road Equipment: 1 Cement and Mortar Mixers (10 hp) operating at a 0.56 load factor for 8 hours per day 4 Off Highway Trucks (479 hp) operating at a 0.57 load factor for 8 hours per day 2 Rubber Tired Dozers (357 hp) operating at a 0.59 load factor for 6 hours per day 1 Tractors/Loaders/Backhoes (108 hp) operating at a 0.55 load factor for 7 hours per day Phase: Trenching 8/1/ /31/ Phase II Off-Road Equipment: 1 Bore/Drill Rigs (291 hp) operating at a 0.75 load factor for 8 hours per day 1 Concrete/Industrial Saws (10 hp) operating at a 0.73 load factor for 8 hours per day 1 Generator Sets (549 hp) operating at a 0.74 load factor for 8 hours per day 1 Pavers (100 hp) operating at a 0.62 load factor for 8 hours per day Phase: Paving 11/1/ /30/ Phase III - Conservative because revegetation would be less equipment intensive Acres to be Paved: 0.53 Off-Road Equipment:

17 Page: 1 5/3/ :08:41 AM 1 Cement and Mortar Mixers (10 hp) operating at a 0.56 load factor for 6 hours per day 1 Generator Sets (549 hp) operating at a 0.74 load factor for 8 hours per day 1 Pumps (53 hp) operating at a 0.74 load factor for 8 hours per day 1 Tractors/Loaders/Backhoes (108 hp) operating at a 0.55 load factor for 7 hours per day Construction Mitigated Detail Report: CONSTRUCTION EMISSION ESTIMATES Annual Tons Per Year, Mitigated ROG NOx CO SO2 PM10 Dust PM10 Exhaust Fine Grading 07/01/ Fine Grading Dust Fine Grading Off Road Diesel Fine Grading On Road Diesel Fine Grading Worker Trips Mass Grading 08/01/ Mass Grading Dust Mass Grading Off Road Diesel Mass Grading On Road Diesel Mass Grading Worker Trips Trenching 08/01/ /31/ Trenching Off Road Diesel Trenching Worker Trips Asphalt 11/01/ /30/ Paving Off-Gas Paving Off Road Diesel Paving On Road Diesel Paving Worker Trips PM10 PM2.5 Dust PM2.5 Exhaust PM2.5 CO Construction Related Mitigation Measures The following mitigation measures apply to Phase: Fine Grading 7/1/2011-7/31/ Phase I For Soil Stablizing Measures, the Apply soil stabilizers to inactive areas mitigation reduces emissions by: PM10: 84% PM25: 84%

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