City of Berkeley Transfer Station Air Quality Evaluation and Recommended Mitigation Measures

BERKELEY TRANSFER STATION
Air Quality Evaluation and Recommended Mitigation Measures


BERKELEY TRANSFER STATION Air Quality Evaluation and Recommended Mitigation Measures ESA Environmental Science Associates, April 29, 2003 City of Berkeley Public Works Department Berkeley, California 94704 TABLE OF CONTENTS I. INTRODUCTION Background II. FINDINGS Review of Previous Studies Additional Microscale Considerations Dispersion Modeling Dust Observations III. ADDITIONAL CONTROL MEASURES Operational Controls Architectural Measures Offsite Control Measures (not included) IV. CONCLUSIONS AND RECOMMENDATIONS LIST OF FIGURES 1 Project Location 2 Diurnal Pattern Over Entire Study Period, Harrison Park Monitor 3 PM10 Sources at Worst-Case Offsite Location 4 Dust is generated when loads are emptied 5 Greenwaste does not generate visible dust 6 Hanging Baffle System 7 Wind Break Fence(s) 8 Building Enclosures TABLE 4-1 Estimate of Control Measure Effectiveness (not included) I. INTRODUCTION The City of Berkeley has retained Environmental Science Associates (ESA) to: • review recent studies of air quality near the Berkeley Transfer Station; in the context of determining potential future air quality mitigation measures; • review the appropriateness of air quality mitigation measures already implemented at the Berkeley Transfer Station; and • recommend other measures at the Berkeley Transfer Station that could further improve air quality at the transfer station and in the vicinity of the transfer station. Chapter 2 of this report reviews the methodologies and conclusions of recent air quality studies that have been conducted near the Berkeley Transfer Station. Chapter 2 also analyzes the effectiveness of the levels of respirable particulate matter (PM10) (dust) 1 control measures that were installed in 2002 and 2003. Additional control measures are presented in Chapter 3 and analyzed for their potential to further reduce PM10 generated by operations at the transfer station. Chapter 4 presents conclusions and recommendations about the previous air quality assessments and dust control mitigations. BACKGROUND An annotated aerial photo of the Berkeley Transfer Station and the surrounding areas to the east are shown in Figure 1. As can be seen in Figure 1, the Transfer Station is just east of Interstate 80 in an industrial area of Berkeley north of Gilman Street. Figure 1 does not show the additional industries in this area that are located just south of Gilman Street. There are two land uses just east of the Berkeley Transfer station that are sensitive to air quality. These uses are the Harrison Field soccer field and the Ursula Sherman Village (USV). Air quality measurements conducted to determine the PM10 at the soccer field began in 2001. These measurements indicated that dust from the transfer station is contributing to air quality levels downwind that frequently exceed the state standard for PM 10. As noted above, the Berkeley Transfer Station has already implemented mitigation measures intended to reduce PM10 at the transfer station and downwind of the transfer station at the soccer field and at Ursula Sherman Village. The Berkeley Transfer Station is not in violation of any known air quality regulations, but intends to continue implementing measures that will improve air quality in a cost efficient manner. Measures already implemented include the use of B 100 biodiesel fuel to reduce emissions from diesel engines that the City operates, adding new route trucks that are fueled by compressed natural gas (CNG), addition of a misting system to "wet" dust on-site, installation of a perimeter fence to the east of the transfer station that will be covered with vines (to block the pathway of PM10 leaving the site), and adding trees to reduce on-site winds and the transport of dust. ESA's overall assessment of the transfer station indicates that the transfer station has already implemented three important proactive air quality measures that are very common among modern transfer stations: (1) the high-pressure mist system to reduce dust in the tipping area, (2) the use of B100 biodiesel fuel for diesel engines, and (3) new route trucks that are fueled with CNG. In Chapter 4 ESA recommends several measures that could further reduce dust levels on-site and off-site. It can be concluded that, although the transfer station certainly contributes to ambient PM10 concentrations at the soccer field and the USV site, the magnitude of the contribution would be smaller than levels reported at the monitor PM10 station, under the same conditions. This is because the PM10 monitoring location was selected at the worst-case location, and dispersion modeling described in this report indicates PM10 concentrations would fall rapidly at greater distances. II. FINDINGS REVIEW OF PREVIOUS STUDIES ESA has reviewed the two reports prepared by Environ for BOSS (Building Opportunities for SelfSufficiency) that address air quality at the proposed site of USV: Final Report on Air Quality at the Proposed Site of the Ursula Sherman Village, March 15, 2002. ENVIRON International Corporation Update on Air Quality at the Proposed Site of the Ursula Sherman Village, September 30, 2002. ENVIRON International Corporation These studies reported the results of analyses of PM10 and PM2.52 ambient air measurements collected at a location that is generally downwind of Berkeley Transfer Station. Applied Measurement Science, a company that was under contract with the City of Berkeley, collected the PM10 and PM2.5 data. ESA has also reviewed the following two Draft reports prepared by Applied Measurement Science. PM10/PM2.5 Monitoring at Harrison Park, Berkeley, California, March 20, 2003 PM/10 Monitoring at the Berkeley Recycling Center Materials Recovery Facility July, 2002 to January, 2003, March 14, 2003 The most obvious conclusions from these reports are the following: • PM2.5 levels do not appear to correlate to the operating hours of the transfer station and have been dismissed by both the Environ study and Dr. Weinegar as not being a major effect of transfer station operations. PM2.5 will not be further discussed, for the most part, in the remainder of this report. ESA's additional research has found that the City's use of B 100 biodiesel fuel at the transfer station should already be reducing the PM10 emissions from diesel engine use by approximately 50 percent. B 100 fuel also reduces carbon monoxide emissions by 50 percent and hydrocarbon emissions by more than 50 percent. 3 • Background PM10 levels in this area (meaning the 1/4 mile area that surrounds the Berkeley Transfer Station) are as high as 39 micrograms per cubic meter (ug/m3). Dr. Weinegar identified the following long-term averages from his report 4: These averages were determined in most cases from thousands of hourly data points. The measurement equipment was tested by the Bay Area Air Quality Management District (BAAQMD) audit team and was found to be operating properly. Dr. Weinegar's report further indicates: "The value of 39 ug/m3 can be considered an upper bound to the background level at Harrison Park. It is considered an upper bound because the Park is a couple hundred yards from the recycling center and the other sources and therefore that background level would be diminished somewhat by the distance from the recycling center to the monitoring site at the park. Therefore, the value of 39 ug/m3 is considered as a background concentration to Harrison Park. This relatively high background level shows the impact of the highways and industrial sources in the area, which will be further considered in the section comparing Harrison Park data to other monitoring sites in the Bay Area." • The PM10 levels measured in these reports are not directly comparable to other Bay Area regional measurements (collected by the Bay Area Air Quality Management District [BAAQMD]) because the BAAQMD does not measure directly downwind of minor sources. • The effect on PM10 concentrations from the Berkeley Transfer Station can best be understood by a plot of the hourly data over the length of the monitoring efforts. The average hourly plot for the Harrison Park PM10 monitor is shown in Figures 2 and 3. They clearly show the background level of approximately 40 ug/m3 in the hours when the transfer station is normally closed and show an increase of about 30 ug/m3 (resulting in total concentrations of up to 68 ug/m3) during the hours when the transfer station is operating. ESA has reviewed all the background reports identified above and believes this increased PM10 burden during transfer station operating hours is the result of transfer station operations. Figure 3 shows an overview of the sources of the PM 10. The Bay Area background is approximately 20 ug/m3. Added to that is a local West Berkeley background component of approximately 10 to 20 ug/m3. Finally, on top of both, the PM10 from the Berkeley Transfer Station is added to Bay Area regional and local West Berkeley background PM10 concentrations. As described under the dispersion modeling write-up below, the PM10 measured for the transfer station was measured at a worst-case offsite location. • The California state PM10 24-hour standard of 50 ug/m3 is violated regularly throughout the state (even when measured at representative neighborhood locations that are not directly downwind of a transfer station or other industrial source of dust). The federal 24-hour standard (150 ug/m3) is three times higher than the state standard and was not violated in any of the PM10 measurements. Source: PMIO/PM2.5 Monitoring at Harrison Park; March 20. 2003 Figure 2 Diurnal Pattern Over Entire Study Period Harrison Park Monitor Source: PM10/PM2.5 Monitoring at Harrison Park: March 20. 2003; and Environmental Science Associates Figure 3 PM 10 Sources at Worst-Case Offsite Location No specific standard exists for worker exposures to dust generated from transfer stations. However, a general category of "particulates not otherwise regulated" exists to handle this kind of situation. The OSHA permissible exposure level (PEL) for particulates otherwise not regulated is 15 mg/m3 (15,000 ug/m3 for total dust) and 5 mg/m3 (5,000 ug/m3) for respirable dust (generally the same as PM10). The prior reports on this data have pointed out the Los Angeles area has higher PM10 levels than what has been measured at Harrison Park. 5 "Six-month average PM10 concentrations in and around Los Angeles were generally higher than those measured at Bay Area sites or at the soccer field. As expected, concentrations at most Los Angeles monitors were highest during the winter months, when the reported peak concentrations tended to occur. As was the case in the Bay Area, peak 24-hour average PM10 concentrations varied quite a bit between different Los Angeles monitoring sites. Many of these peaks [in Los Angeles] were higher than the peak 24-hour PM10 concentration measured at the soccer field (86.3 ug/m3). The highest 24-hour average PM10 concentration measured in the Los Angeles (166 ug/m3 in Ontario) was nearly twice as high as the peak 24-hour soccer field concentration." ADDITIONAL MICROSCALE CONSIDERATIONS Environ based part of its Final Report conclusions on the impacts of PM 10 sources on the USV site, based on a highway monitoring study. The report states: The application of the results in an article describing the results of a PM 10 monitoring study conducted in St. Louis, Missouri in 1999, however, suggests that PM 10 impacts on the West Berkeley area due to the freeway are probably limited. According to this report, downwind PM10 concentrations measured at several locations near freeways showed linear decreases with increasing distance from the freeway. At each location, PM 10 concentrations measured downwind of the freeway dropped off to match upwind levels at a distance of 70 meters (230 feet) from the freeway.(6) As the proposed Ursula Sherman Village would be more than 700 feet from the freeway, if the results of the St. Louis study hold in West Berkeley, it is unlikely that the freeway results in increased particulate concentrations at the proposed USV. ESA believes this same argument can hold with regard to the Transfer Station, since the PM10 monitor is less than 70 meters away from the Transfer Station, but most areas of the soccer field and the USV project site are greater than 70 meters from the Transfer Station. One could conclude that the actual PM10 concentrations at most areas of USV and the soccer field would be lower than the levels reported in the Environ reports. Applied Measurement Science described the placement of the PM10 monitor as follows: "The specific monitoring location at the park was selected on the basis of several criteria. First, a worse case location--e.g., a location close to the western side of the park--was selected so that there would be a built- in conservatism in all data collected." DISPERSION MODELING A screening modeling analysis was conducted by ESA using the EPA dispersion model SCREEN3 to confirm these assumptions and to track predicted PM10 ambient air concentrations as a function of downwind distance from the Transfer Station. The Transfer Station was assumed to be a square area emission source approximately 30 meters on a side. Unit emissions were assumed for the source. The model predicted downwind ambient air concentrations at the soccer field and at the USV location, relative to concentrations that would occur at the monitor location. Typical daytime neutral atmospheric stability with wind speeds of 3 meters per second (6.5 mph) were assumed in the model. The predicted levels at the soccer field (a distance of 120 meters from the east doors of the transfer station) were about one third the levels predicted at the monitor location, and levels at the USV location (a distance of 100 meters from the east doors of the transfer station) were about one half the levels at the monitor location. As stated above, the monitor location was assumed to be about 60 meters from the Transfer Station building in the screening modeling analysis, while the soccer field was assumed to be about 120 meters away with the USV site being about 100 meters away. Thus, on days when PM10 concentrations were measured at the Harrison Park monitor, corresponding levels (associated with the component of the PM10 that came from the Transfer Station) at the soccer field and at the proposed USV site would be lower than levels reported for the monitor location. It can be concluded that, although the transfer station certainly contributes to ambient PM10 concentrations at the soccer field and the USV site, the magnitude of the contribution would be smaller than levels reported at the monitor PM10 station, under the same conditions. An example based on Figure 3 is probably helpful: Site 1 (Distance 60 meters from transfer station). At the Harrison Park PM10 monitor (60 meters downwind from the transfer station) the PM1O concentration averaged 68 ug/m3 at 13:00 hours. This is made up of a local background concentration of approximately 40 ug/m3 and a local source contribution (the Berkeley Transfer Station) of 28 ug/m3. The total is 40+ 28 =68 ug/m3 Site 2 (Distance 100 meters from transfer station). Based on the results of the dispersion modeling, at a distance of 100 meters from the transfer station (such as USV locations) the concentration for this same hour would be predicted to be about 54 ug/m3. This still includes the local background concentration of approximately 40 ug/m3 but only one half of the local source concentration (Berkeley Transfer Station), or about 14 ug/m3. The total is 40+ 14=54 ug/m3 Not withstanding this information, PM10 concentrations could be lowered at the USV site, if the Transfer Station adopts additional mitigation measures (See Chapter 3). Theoretically the levels at USV could be reduced to the background average level of about 40 ug/m3, but no actions at the transfer station could lower the average levels below 40 ug/m3, which is the local background PM10 concentration. In addition, the USV building could be designed to efficiently filter indoor air, which would improve indoor air quality regardless of the source of the PM10 (i.e., regional, the Transfer Station, Interstate 80, other industrial operations). DUST OBSERVATIONS ESA staff made several Transfer Station site inspections to review operations and make observations. We initially expected to see the predominant southeast winds whipping though the building and generating clouds of dust that would be transported to the east. We did not observe this, and actually we now believe the wind to be less of factor in dispersing the dust than was previously thought. We do believe the wind can help transport dust to the east, but the consistency of the daily PM 10 cycles (at the measurement location) does not seem dependent on the daily winds. The energy from the handling of the waste materials and the configuration of the building may be all that is necessary to move dust out of the building to the nearby PM10 monitor. TRANSFER STATION DUST: (MAJOR DUST SOURCE) The energy that stirs up the dust comes from (1) dropping dusty materials out of the public and City trucks onto the floor of the transfer station [see Figure 41(2) the wheeled loader picking up the materials and (3) the wheeled loader pushing the loads into the top of the transfer trucks. Each of these actions creates a visible dust plume with most loads, and this energy along is probably enough to expel PM10 from the building (via the openings in the transfer station building). GREENWASTE HANDLING DUST (MINOR SOURCE) Observations at the Transfer Station indicated that the handling of greenwaste is not a major generator of dust [see Figure 5]. Some dust is generated by the unloading of greenwaste and indirectly, greenwaste load will cause dust because of the re-entrainment of dust caused by the vehicles delivering greenwaste to the transfer station. VEHICLE DUST RE-ENTRAINMENT (MEDIUM DUST SOURCE) Vehicles traveling on all roads re-entrain dust that has settled on the road. The dust on the pavement at the transfer station is constantly being stirred up by vehicles on the site. This creates energy to move PM 10 from the site, with or without the help of the wind. DIESEL EMISSIONS (MINOR SOURCE) The wheeled loader belches black diesel exhaust frequently during operations. Diesel exhaust is also generated by the fleet vehicles when unloading, parking, or moving about on the site. Site observations indicate that diesel vehicles are only operated when necessary, and the entire fleet is using B 100 biodiesel fuel that reduces emissions. Since diesel exhaust is primarily PM2.5, the lack of any PM2.5 spikes at the Harrison Park monitoring station indicates that diesel exhaust from the Berkeley Transfer Station is not a major factor to the neighboring land uses. The effects of diesel exhaust are probably more of an issue for the on-site workers and the general population of Berkeley (since the fleet trucks travel throughout the City and do bum considerable amounts of fuel). IV. CONCLUSIONS AND RECOMMENDATIONS ESA has reviewed the extensive database of PM10 and PM2.5 measurements that have been collected immediately downwind of the Berkeley Transfer Station. The measurements indicate that the Berkeley Transfer Station does contribute to the downwind PM10 burden (at a location 60 meters east of the transfer station doors) by an annual average concentration of about 6 ug/m3. During hours of operation, the annual average downwind concentrations at this same location increases up to about 70 ug/m3 (about 30 ug/m3 above the local West Berkeley background level). The local West Berkeley background level of PM10 is approximately 40 ug/m3 and does not vary much from hour to hour. The average 24-hour PM10 level at BAAQMD monitoring locations (the regional background) is approximately 20 ug/m3. There is no evidence that indicates the Transfer Station has a measurable effect on downwind PM2.5 concentrations. There is considerable concern regarding the expansion of USV to a location immediately downwind of the Transfer Station near the location of the PM10 and PM2.5 measurements. It is a classic land use decision, "How close should residents be to industrial facilities?" Dispersion modeling by ESA indicates that PM10 levels drop dramatically in the range of 60- 120 meters from an area source of PM10 (such as the Transfer Station). So, the size of the buffer area between the transfer station and the USV will be a primary factor in the resulting PM10 concentrations at USV. The PM10 monitoring was conducted at a worst-case location and PM10 levels associated with the transfer station would be considerably reduced at the actual USV buildings (as proposed). Any additional movement of those buildings away from the Berkeley Transfer Station would have additional benefits according to the dispersion modeling conducted for this study. There is currently no data that indicates the effectiveness of the control measures that have been installed at the transfer station (i.e., the mist system and the eastern fence). ESA believes these are both are good mitigation measures and will reduce the PM10 levels, especially with the fine-tuning of the mist system. The use of B 100 biodiesel fuel is also a positive factor in reducing PM10 and PM2.5 at the Berkeley Transfer Station. Using new CNG-powered route trucks is also an excellent proactive measure implemented on 4 new route trucks. Future decisions regarding fuels and engine controls need to fully consider compliance with the upcoming ARB Rule regarding garbage truck fleets. Several new control measures have been identified in this report. Each of these measures will reduce PM10 leaving the site. The most effective and most costly measures involve enclosure of the transfer station. The following is ESA's summary assessment of the measures identified in Chapter 3. 1) PM10 is respirable particulate matter with aerometric diameter of equal to or less than 10 microns. It is a recognized air pollutant and is essentially: "fine dust particles." Typical dust will contain particles greater than 10 microns and less than 10 microns. This report will use the terms dust and PM10 relatively interchangeably. This report will clearly identify measurements of PM10 as being PM10 because that is all that is collected in the measurements. When referring to mitigation measures for PM10 the report will often refer to dust mitigations -- since reducing the dust will reduce the PM10. 2) PM2.5 refers to particulate matter that is 2.5 micrometers or smaller in size. 2.5 micrometers is approximately 1/30 the size of a human hair; so small that several thousand of them could fit on the period at the end of this sentence. The sources of PM2.5 include fuel combustion from automobiles, power plants, wood burning, industrial processes, and diesel-powered vehicles such as buses and trucks. These fine particles are also formed in the atmosphere when gases such as sulfur dioxide, nitrogen oxides, and volatile organic compounds (all of which are also products of fuel combustion) are transformed in the air by chemical reactions. 3) US EPA, A Comprehensive Analysis of Biodiesel Impacts on Exhaust Emissions, Draft Technical Report, EPA42O-P-02001, October 2002. 4) PMI0/PM2.5 Monitoring at Harrison Park. Berkeley, California, March 20, 2003; Prepared by Applied Measurement Science. 5) Final Report on Air Quality at the Proposed Site of the Ursula Sherman Village, March 15, 2002. ENVIRON International Corporation. 6) Lamoree, David P., and Turner, J.R., 1999, "PM Emissions emanating from Limited Access Highways," Journal of the Air and Waste Management Association Volume 49: PM-85-94. September."