Attachment I - Wind Roses from Soccer Field Meteorological Data
(July 2001-March 2002)
Attachment 2 - Memorandum from Eric D. Winegar dated September 23, 2002
BOSS (Building Opportunities for Self-Sufficiency) is proposing to develop the Ursula Sherman Village, a planned community designed to provide emergency and transitional housing. BOSS has performed an air quality assessment of this area, which was summarized in a final report dated March 15, 2002. This update includes additional data collected since the time of the final report, as well as additional analyses of the measured PM2.5 data, PM10 data and the meteorological data taken at the site.
PM2.5 data from the Harrison Street site are difficult to interpret, but suggest that PM2.5 is a regional problem rather than a local one. The amount of PM2.5 data has been limited due to technical problems with PM2.5 monitoring equipment and the meteorological equipment. Anomalies in the data suggest further issues with available PM2.5 data for this site.
PM10 concentrations at the Harrison Street site appeared to be higher than at other Bay Area locations in 2002. Evaluations of available data clearly point to the West Berkeley Waste Transfer Station as the cause of elevated PM10 concentrations at the site. PM10 and PM2.5 concentrations measured at this site, however, are typical of concentrations measured in other urban areas.
A dust control system recently installed at the West Berkeley Waste Transfer Station has resulted in some air quality improvements for this area. Visible dust emissions from this facility, which are regulated by the Bay Area Air Quality Management District (BAAQMD) regulations, continue to be observed. An evaluation of the West Berkeley Waste Transfer Station compliance with BAAQMD regulations should be conducted.
The City of Berkeley has proposed additional measures to mitigate emissions from the Transfer Station within the next few months. Based on the available data, it appears that, without the emissions from the Transfer Station, owned and operated by the City of Berkeley, the PM10 concentrations at the project site would be similar to air quality at other locations in the Bay Area.
BOSS (Building Opportunities for Self-Sufficiency) is proposing to further develop the Ursula Sherman Village, a planned community designed to provide emergency and transitional housing, and social services for community residents. Figure 1 shows a map of the proposed project site in relation to the surrounding area. Due to concerns about elevated particulate concentrations in the area of the Harrison Street site voiced by City of Berkeley staff and community members, BOSS contracted with ENVIRON International Corporation to perform an air quality assessment of this area. The results of this assessment were summarized in a March 15, 2002 report entitled "Final Report on Air Quality at the Proposed Site of the Ursula Sherman Village." This report is an update to the final report and includes additional data collected to date, as well as additional analysis and information.
Three pollutants of potential concern were analyzed in this report: hexavalent chromium, particulates less than 2.5 micrometers in diameter (PM2.5), and particulates less than ten micrometers in diameter (PM10). Of these, only PM10 was found to have elevated concentrations near the Harrison Street site compared to other Bay Area locations. Concentrations measured at the Harrison Street site were found to be higher than those at other Bay Area locations during summer months only, and were within the range of concentrations measured in other urban areas.
A preliminary review of the available monitoring data indicated that the West Berkeley Waste Transfer Station was the cause of elevated PM10 concentrations at the Harrison Street site. The report concluded that a dust control system planned for this facility would likely result in air quality improvements for this area.
The dust control system was installed at the West Berkeley Waste Transfer Station in the last week of May 2002. This update has therefore been prepared to review the effects of the addition of this system on PM10 concentrations near the Harrison Street site. This update also includes a discussion of PM2.5 concentrations monitored near the Harrison Street site since the time of the Final Report.
This report contains analyses of PM10, PM2.5, and meteorological data gathered at the Harrison Street site, as well as comparisons of this data with data measured elsewhere in the Bay Area. In some cases, technical issues with monitoring equipment have limited the amount of data available for the Harrison Street site. Issues with PM2.5 monitoring data are discussed in the analyses presented below. Meteorological data was only gathered between July 2001 and March 2002. Wind roses showing wind speeds and directions for the Harrison Street site for selected time periods are included in Attachment 1.
2.0 Air Monitoring Data
An ongoing study has been commissioned by the City of Berkeley to monitor airborne concentrations of particulate matter at the Harrison Street soccer field. Applied Measurement Science has been hired to perform this monitoring, and data collected as part of this work can be obtained on the web at: http://www.airmeasurernent.com The data monitored during this study are assumed to be representative of air quality at the Harrison Street site.
At the time of the Final Report, concentrations measured at the soccer field site were available for the period between July 2001 and February 2002. An addendum to the Final Report included monitoring data through March 2002. At the time this update was prepared, soccer field monitoring data were available up through August 2002.
The Bay Area Air Quality Management District (BAAQMD) monitors PM10 and PM2.5 data at various locations around the San Francisco Bay Area. The locations of these monitors are shown in Figure 2, and the site codes for these monitoring locations are listed in Table 1. The data collected by the BAAQMD is generally available several months after the data collection, so the data from the BAAQMD presented in this report is not as current as the soccer field data. However, where possible, the available air quality data measured at the Harrison Street soccer field have been compared with data measured at other Bay Area monitoring locations.
2.1 Update on PM10 Data
A comparison of monthly average PM10 concentrations at the soccer field with various Bay Area locations is provided in Table 2. As seen in this table, PM10 concentrations measured in 2002 at the soccer field have been higher than PM 10 concentrations measured elsewhere in the Bay Area during corresponding months. In the Final Report, which included data up to February 2002, this appeared to be the case only for the summer months. In the spring of 2002, however, PM10 concentrations appear to be higher at the soccer field than at other Bay Area monitors. As in the summer of 2001, PM10 concentrations at the soccer field were also elevated in the summer of 2002.
Concentrations measured at the soccer field in 2002 also show trends that do not follow the patterns consistent to other Bay Area monitoring locations. For example, monthly PM10 concentrations at the soccer field rose steadily each month from January to May, and have dropped slightly in June, July, and August. The monthly PM10 concentration monitored in May 2002 at the soccer field (53.8 ug/m3) was the highest average monthly concentration measured at that monitor since data was first collected in July 2001. No other Bay Area monitor has increased continually from January to May in 2002. At most locations, concentrations fluctuated between January and June (the latest month for which BAAQMD data are available), with May being the lowest monthly average for most locations.
The failure of the soccer field concentrations to follow the pattern seen at other Bay Area monitors is consistent with the hypothesis, put forth in the Final Report, that a local source of PM10 overwhelms the trends seen at other monitoring locations. In the Final Report, the most likely source of elevated PM10 appeared to be the Transfer Station. An analysis of the more recent data further supports that conclusion. Other possible sources of PM10 are also discussed in Section 2.3 and in the data analyses presented in Section 3.
2.2 Update on PM2.5 Data
PM2.5 data has only been available since January of 2002. Equipment issues prevented the earlier implementation of this monitoring program. At the end of June 2002, an equipment issue resulted in the invalidation of data until the present time. This issue is discussed in a September 23, 2002 memo from Eric D. Winegar included in this update as Attachment 2. As a result of this equipment issue, data from late June 2002 to the current time has been invalidated and will not be discussed here.
A comparison of monthly average PM2.5 concentrations at the soccer field and at various Bay Area locations is provided in Table 3. From January 2002 and February 2002, PM2.5 concentrations at the soccer field were similar to concentrations monitored elsewhere around the Bay Area. This was also true in April 2002. However, March, May and June PM2.5 concentrations were between 50% and nearly twice as high as any other Bay Area monitor.
Figure 3 shows a comparison of monthly average PM10 and PM2.5 concentrations from the soccer field monitor. As seen in this figure, monthly PM2.5 concentrations at the soccer field have not followed the same pattern as PM10. From January to June 2002, PM2.5 and PM10 appear to follow exactly opposite trends, with one increasing during months when the other decreases. This is somewhat surprising since PM2.5 is a subset of PM10, and this trend is not seen at any other Bay Area monitoring location.
PM2.5 levels in March, May and June 2002 were significantly higher than concentrations monitored at other Bay Area monitors. It is therefore possible that the soccer field is affected by a local source of PM2.5. It is also possible, however, that there have been additional technical issues with data collection that have not yet been identified. This is supported by the fact that soccer field PM2.5 does not follow the patterns followed by soccer field PM10 or by PM2.5 at any other Bay Area monitor. Further PM2.5 data analyses are included in the following sections.
2.3 Effectiveness of Transfer Station Dust Controls
As noted above, dust controls were installed at the West Berkeley Waste Transfer Station in the last week of May 2002. These controls consist of a water spray system that wets the waste piles in the Transfer Station warehouse in order to reduce dust emissions generated by the movement and handling of wastes.
At the time of this update, three months of concentration data have been collected at the soccer field monitor with Transfer Station dust controls in operation. As seen in Table 2, PM10 concentrations monitored at the soccer field in June, July, and August were each lower than those monitored during April and May. The lower soccer field PM10 concentrations measured in June and July 2002 likely reflect the influence of the Transfer Station dust control system.
As also seen in Table 2, every other Bay Area monitor recorded higher PM10 concentrations in June than in May. In general, PM10 concentrations reflect area-wide changes in meteorology. The most probable explanation of the reduced concentrations monitored at the soccer field in June and July is therefore a reduction in emissions from the local source that caused the elevated concentrations in 2001 and early 2002. The monthly concentration recorded in July was the lowest at that location since January.
Although lower PM10 concentrations have been monitored at the soccer field after the Transfer Station dust control system was installed, these concentrations are still above those monitored at other Bay Area locations. There are a number of reasons why this may be the case. Since the dust controls were only installed at the end of May, their effectiveness may have been limited during the first, "break-in" month after installation.
Although we have data up through August at the soccer field, we have only one month of data (June 2002) for comparison with other BAAQMD monitors since dust controls were installed at the Transfer Station. However, based on the higher concentration recorded in August compared to historical BAAQMD data, it appears as if a local source of PM10 may still be impacting the soccer field.
It is possible that the Transfer Station controls are not fully effective in reducing the impact of its dust. It is also possible that another source of PM10 caused June soccer field PM10 levels to continue to be above those measured at other Bay Area locations. Other than the Transfer Station, possible local sources that could be responsible for elevated soccer field PM10 concentrations include the following:
• Highway 1-80
• Industrial Sites
• Pacific Steel
• Precision Technical Coatings
• Berkeley Community Conservation Center
The locations of Highway 1-80 and of the industrial facilities listed above (including the Transfer Station) relative to the Harrison Street site can be found in Figure 1. In the Final Report, the Transfer Station appeared to be the most likely source of elevated PM10 concentrations for a few reasons. First, this facility is located approximately 700 feet directly upwind from the Harrison Street site. Secondly, the daily profile of PM10 concentrations (i.e., times when concentrations rise, peak and fall each day) is very similar to the operating hours of the Transfer Station. Lastly, PM10 concentrations showed a similar rise-and-fall profile every day of the week except Sunday, the only day when the Transfer Station is closed.
The daily profile analysis of PM10 concentrations discussed above has been updated using data obtained since the time of the Final Report. Additional analyses have also performed to determine whether another source of PM10 may be contributing to soccer field PM10 concentrations. The same analyses have also been prepared for PM2.5 concentrations. The results of these analyses are discussed in the following section.
3.0 Data Analyses
Two types of data analyses have been prepared in an attempt to identify the local sources of PM2.5 and PM10 causing elevated particulate levels at the Harrison Street site. In the Final Report prepared for this project, an analysis of hourly and daily variations in PM10 was prepared. This analysis has been updated with the most recent PM10 monitoring data available, and a similar analysis has been prepared for PM2.5. A second analysis of the correlation between wind direction and soccer field concentrations has also been prepared for both pollutants.3.1 Daily Profile Analysis - PM 10 As noted above, the Final Report for this project contained a table showing the daily PM10 profile for the soccer field monitoring data. This data showed the average soccer field PM10 concentrations for each hour of the day, and for each day of the week.
The same analysis has been prepared for PM 10 data collected both before and after the dust control system was installed at the West Berkeley Waste Transfer Station. Figure 4 represents the daily PM10 profile for the pre-control scenario, and contains data monitored between March and May 2002. Figure 5 represents the daily PM10 profile for the post-control scenario, and contains data monitored between June and August 2002.A review of the data in both of these figures shows that, for six days per week (weekdays and Saturdays), the PM10 concentrations begin each day at relatively low levels, steadily increase until about noon, and then slowly decrease. On Sundays, the levels are approximately the same throughout the day.
As noted in the Final Report, the daily PM10 profiles discussed above correspond very closely to the Transfer Station's hours of operation. The Transfer Station operates six days per week (Monday through Saturday) and has peak waste-moving operations from 8 a.m. to 12 p.m., with substantial operations continuing until 2 p.m.The daily and hourly profiles indicate that the freeway is not the cause of elevated PM 10.
Were concentrations at Harrison Street impacted mainly by Highway 1-80, weekday air pollution concentrations would be expected to peak during the periods of heaviest traffic (i.e., morning and evening rush hours). Also, Saturday and Sunday patterns would be expected to be different from weekday patterns. Instead, weekday PM10 concentrations rise steadily luring the day, peak just after noon, and steadily drop again. In addition, as can be seen in Figures 4 and 5, the pattern is consistent on weekdays and Saturdays, and is different on Sunday. On Sundays, when the Transfer Station is closed, PM10 levels do not show the same rise-and-fall pattern as other days. Noontime concentrations on Sundays are nearly identical to those measured at midnight.
The general pattern of the daily PM10 profile was the same both before and after dust controls were added at the Transfer Station. The main difference between Figures 4 and 5 is that the profile curves are shifted downwards after controls were added. So, the average, peak PM10 concentrations during days when the Transfer Station was in operation were lower after controls were added.
3.2 Daily Profile Analysis - PM2.5
A daily profile was also prepared for soccer field PM2.5 concentrations. This analysis was not prepared in the final report since, at that time, PM2.5 concentrations did not appear to be higher at the soccer field than at other Bay Area monitors. Profiles for both the pre-control and post-control scenarios have been prepared. Figure 6 represents the daily PM2.5 profile for the pre-control scenario, and contains data monitored between March and May 2002. Figure 7 represents the daily PM2.5 profile for the post-control scenario, and contains data monitored in June 2002. As noted above, due to technical issues with PM2.5 data monitored in July and August 2002, this data has not been included in this analysis.
The daily profiles for PM2.5 do not show significant variation as the PM10 profiles. For the pre-control data in Figure 6 (March - May 2002), PM2.5 concentrations were relatively constant on most days. Daytime concentrations were slightly higher than nighttime concentrations on weekdays and Saturdays, but the differences were relatively small and the changes were very gradual, compared to the PM10 profiles. These trends suggest that PM2.5 in this area is a regional issue, and that local sources such as the 1-80 freeway or the Transfer Station do not impact PM2.5 levels as dramatically as they affect PM10 levels. The post-control graph (Figure 7) contains only one month of data (June 2002). This data therefore shows more variability, but the trends are similar to the trends seen in the precontrol scenario.
There are also patterns in the PM2.5 data that are difficult to explain. For example, in both the pre-control and post-control graphs, Sunday PM2.5 concentrations appear to be higher at night than during the day. This same effect is seen in Saturday concentrations measured in June 2002, although this data reflects only a few days, so it may not represent a long-term pattern. As discussed above, PM2.5 profiles appear to reflect regional effects, and not the effects of a local source. As a result, one might expect that PM2.5 concentrations should be similar to those measured at other Bay Area monitors. This is true for certain months, but not others. The lack of a distinct pattern matching a local source, along with noted data anomalies, suggest that there may be technical issues with the PM2.5 data monitored prior to July and August 2002 (when specific issues with PM2.5 data were identified).
3.3 Concentration Rose Analysis - PM10
A second analysis has been prepared to help determine the source of elevated PM10 concentrations at the Harrison Street site. In this analysis, PM10 concentrations at the soccer field have been sorted by the wind direction at the time these concentrations were monitored. The average PM10 concentrations were then calculated for each wind direction and plotted as a "concentration rose." In these plots, the length and color of the "petal" for each wind direction indicates the average PM10 concentration measured when winds were blowing from that direction.
Meteorological data, including wind speed and direction, have been gathered as part of the soccer field monitoring study. As noted earlier, due to technical problems with the monitoring equipment, wind data are not available for the period after March 2002.Therefore, pre- and post-control analysis based on wind speed could not be conducted. Wind roses for selected periods are included in Attachment I.
A concentration rose was prepared for PM 10 data monitored between July 2001 and March 2002 (shown in Figure 8). From this data, it appears that the highest PM10 concentrations were monitored when winds were blowing from the southwest. As noted above, the Transfer Station is located just 700 feet southwest of the Harrison Street site. The fact that the highest PM10 concentrations are measured when winds are coming from this direction supports the determination that the Transfer Station is the most likely source of elevated PM10 at this site.
To further test this hypothesis, two more concentration roses were prepared. Figure 9 shows the PM10 concentration rose for all hours when the Transfer Station was operating (7 a.m. to 4 p.m., Monday through Saturday), and Figure 10 shows the average PM10 concentration rose for all hours when the Transfer Station was not operating (including all day on Sundays). In these figures, the trends are even more dramatic. During Transfer Station operating hours, PM10 concentrations associated with winds out of the southwest are even higher than in the analysis using all of the data. When the Transfer Station is not operating, however, the resulting analysis shows no correlation between wind direction and PM10 concentrations.
This analysis would yield different results if any of the other possible sources listed above in Section 2.2 were the main source of PM10 concentrations at the Harrison Street site. For example, as seen in Figure 1, Highway 1-80 in this area runs in a north-to-south direction. Were concentrations at Harrison Street impacted mainly by Highway 1-80, PM10 concentrations would be expected to correlate with winds coming generally out of the west (i.e., anywhere from northwest to southwest). Instead, only winds from the southwest are associated with high concentrations. In addition, if the highway were the source of PM10, elevated concentrations would have been seen for winds out of the west during Transfer Station non-operation (since this includes all periods of afternoon rush hour traffic). Instead, no such correlation was seen during these times.
It is also unlikely that other industrial sources are the source of elevated PM10 at the soccer field monitor, since the Transfer Station is the only significant PM10 source located directly to the southwest of this monitor. The other industrial sources of PM10 in the area, Pacific Steel Casting Co. and Precision Technical Coatings, are both located south (and slightly east) of the Harrison Street site. The Berkeley Community Conservation Center has far less PM10 emissions. Unlike the other three industrial sites in this area, the Conservation Center does not require a permit from the BAAQMD since its emissions are so small. *
The concentration rose analysis therefore strongly suggests that the Transfer Station, and not the other possible sources listed above in Section 2.2, is the main source of elevated PM10 concentrations at the Harrison Street site.
3.4 Concentration Rose Analysis - PM2.5
Concentration roses have also been prepared for soccer field PM2.5 data. Since PM2.5 data were not collected at this site until January 2002, and on-site wind data are only available through March 2002, there are only three months with available data required for this analysis. In this time, only PM2.5 concentrations measured in March 2002 were higher at the soccer field than at other Bay Area monitors. Therefore, a separate concentration rose was prepared for January, February and March 2002 to help determine how March may have been different from the previous two months.
The PM2.5 concentration roses for January, February and March 2002 appear in Figures 11, 12, and 13, respectively. Wind roses for these months are included in Attachment 1. The month with the strongest pattern was January, when the highest concentrations were monitored when winds were coming out of the east. The January wind rose shows that wind speeds were much slower this month than in subsequent months, and that winds from the east were often at very slow speeds. Therefore, higher concentrations appear to correlate with periods of stagnation, rather than with a local source.
As seen in Figure 13, PM2.5 concentrations in March did not correlate well with winds from any particular direction. Concentrations were slightly higher when winds were blowing from the northeast or from the southwest, but these differences were small. The results of this analysis were inconclusive for helping determine a source that may be responsible for elevated PM2.5 concentrations at the Harrison Street site. As noted above, the failure of the soccer field PM2.5 data to correlate with any parameters (including data from other monitors, operating times of sources of PM2.5, and winds) may indicate further technical problems with this data that have not yet been identified.
From the analyses presented in this report, it appears that the West Berkeley Waste Transfer Station is the main cause of elevated PM10 at the Harrison Street site. The analyses of PM2.5 are less conclusive, and the lack of discernible patterns may indicate technical problems with the data. This section contains recommendations for future work on this project to further understand air quality issues related to PM10 and PM2.5 in the West Berkeley area and to help address these issues.
4.1 Berkeley Community Conservation Center Monitoring Data
We understand that additional PM10 and PM2.5 monitoring has been performed at the Berkeley Community Conservation Center. As seen in Figure 1, this facility is located just south of the West Berkeley Waste Transfer Station. Since the Conservation Center is located closer to the 1-80 freeway, it is likely that the air quality at this facility is more heavily impacted by the freeway than the soccer field monitor. Since the prevailing winds in the area are from the south and southwest, it is also likely that emissions from the Transfer Station impact this facility less than they impact the soccer field monitor. The data from the monitoring study performed at the Conservation Center would therefore provide an important point of comparison to help determine the source of elevated particulate matter concentrations at the soccer field.
At the time this update was prepared, we have not been able to obtain the air quality data collected at the Conservation Center. We understand that a final report containing this data should be available soon. At that time, a comparison with the soccer field monitoring data will be possible.
4.2 Additional Transfer Station Dust Reductions
As noted above, a dust control system was installed at the West Berkeley Waste Transfer Station in late May 2002. From the available PM10 data collected at the soccer field after the time that this system was installed, it appears that PM10 concentrations have decreased. However, it also appears that average soccer field PM10 concentrations are still above the PM10 concentrations measured at other Bay Area monitoring sites. Since the Transfer Station is still the most likely source of these elevated concentrations, a list of possible additional dust control measures is included below.
These measures were developed based on observations made during a recent visit to the Transfer Station and based on conversations with staff at the Transfer Station and at the City of Berkeley. During a recent visit to this facility, visible dust emissions from various operations were observed. BAAQMD regulates visible dust emissions under BAAQMD Regulation 6, which limits on-site visible emissions to 20% opacity from any source (6-302). This regulation also prohibits off-site visible emissions that cause annoyance to another person (6-305). Based on our observation of visible emissions at the site, ENVIRON recommends a compliance audit of the Transfer Station.
These measures are offered here, as suggestions for further consideration, although their feasibility and dust control effectiveness have not been evaluated.
Dust Control Measure
1. Enhanced water spray system
2. Improved watering of unpaved roads and parking areas within facility
3. Installation of windbreak fence along east side of facility
4 Installation of windbreak along west side of facility
Additional spray nozzles are planned, along with improvements that will increase water flow from existing spray nozzles
Watering on a regular basis (whenever the pavement is dry) would prevent the visible dust plumes currently seen when large trucks travel through the facility.
This measure is currently in the planning stages, and would provide significant dust reduction. The fence design should focus on dust reduction in its design. Currently, lower PM10 concentrations are monitored in the afternoon when large trucks are closely parked in a row along the east side of the facility, acting as a temporary windbreak. The facility is looking into planting a row of trees along the west side of the facility to act as a windbreak.
• PM10 concentrations from the Harrison Street site continued to be higher than those measured at other Bay Area locations in 2002. Concentrations measured at this site are not atypical of concentrations measured in other urban areas.
• PM2.5 data from the Harrison Street site are difficult to interpret, but suggest that PM2.5 is a regional problem rather than a local one. The amount of PM2.5 data has been limited due to technical problems with PM2.5 monitoring equipment. Anomalies in the data suggest further problems with available PM2.5 data for this site.
• Further evaluation of available soccer field monitoring data and meteorological data for this area strongly indicates that the West Berkeley Waste Transfer Station is the cause of elevated PM10 concentrations at the Harrison Street site.
• The dust control system recently installed at this facility has resulted in some air quality improvements for this area. Additional dust control measures at the facility are needed.
• The City has proposed additional measures to mitigate emissions from the Transfer Station within the next few months. The monitoring system currently operating at the site can be used to determine whether the controls at the Transfer Station are effective, or whether additional controls at the Transfer Station are needed.
• Based on the available long-term sampling data, it appears that, without the emissions from the Transfer Station, owned and operated by the City of Berkeley, the PM10 concentrations at the site would be similar to air quality at other locations in the Bay Area.
TO: Ed Murphy, Nabil Al-Hadithy, City of Berkeley FROM: Eric D. Winegar DATE: September 23, 2002 SUBJECT: Erroneous PM2.5 Data