Pacific Southwest, Region 9
Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations
Naturally Occurring Asbestos
El Dorado Hills
Multimedia Exposure Assessment
Preliminary Assessment and Site Inspection Report Interim Final
5.0 Summary of Investigative Efforts (cont'd)
5.4 Air Sampling
5.4.2.2 Rolling Hills Middle School
The logistics of conducting one scenario at Silva Valley Elementary School in the morning, and then moving all the equipment and personnel to Rolling Hills Middle School to conduct two more scenarios took more time than was anticipated. In order to complete scenarios at both the soccer field and the basketball play area at Rolling Hills Middle School before dark, the START cut the length of time the soccer scenario was performed; instead of 2 hours the soccer scenario was stopped after about 1.5 hours of activity had been completed.
Soccer Scenario. The START collected soil samples to test the moisture level immediately prior to conducting the soccer scenario at Rolling Hills Middle School (see Table 5-7: Moisture Levels in Activity Area Soils). The soccer scenario activity was conducted on a rectangular area toward the southern end of the field where the START observed bare areas in the grass.
The START conducted activity-based outdoor air sampling during the soccer scenario on October 3, 2004, according to the following scripted schedule:
- For the entire 1.5-hour scenario, one member of the sampling team simulated the activities of an adult/parent spectator sitting near the edge or walking around and occasionally within the area of play. This member of the sampling team would sometimes retrieve a ball kicked out of the area of play. The intake for the air collection filter cassette worn by this sampling team member was set at a height of about 5 feet.
- For the entire 1.5-hour scenario, five other members of the sampling team passed soccer balls back and forth to each other. They sometimes formed a small circle to practice passing; other times they dribbled the ball across the field with other sampling team members close by. The intakes for the air collection filter cassettes worn by these sampling team members were set at a height of about 3 feet.
Figure 5-6
Silva Valley Elementary School Baseball Playing Field Activity‑Based Outdoor Air Sampling Locations B Baseball Scenario B
(Click image for larger version)
The area within which the START conducted the activity is outlined and the positions of the stationary air sample pumps operating during the soccer scenario are shown as RHS-1FD, RHS-2FD, RHS-3FD, RHS-4FD, and RHS-5FD on Figure 5-7 (Rolling Hills Middle School Soccer Field Activity-Based Outdoor Air Sampling Locations–Soccer Scenario). The position of the mobile meteorological station is shown as RHS-MS. A summary of results for the soccer scenario samples is shown in Table 5-10 (Rolling Hills Middle School Soccer Scenario Air Sample Summary Results). See Appendix B for a summary of the results from dust monitoring during this scenario.
Basketball Scenario. The START conducted the basketball scenario on a half court of one of the basketball courts at Rolling Hills Middle School on October 3, 2004.
Figure 5-7
Rolling Hills Middle School Soccer Field Activity-Based Outdoor Air Sampling Locations B
Soccer Scenario
(Click image for larger version)
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Table 5-10 Rolling Hills Middle School Soccer Scenario Air Sample Summary Results |
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| Sample ID | Location | Location Description | Date | PCME Structures (s/cc) | AHERA-like Total Structures (s/cc) | Sensitivity (s/cc) |
| RHS-H2-1FD-100304 | RHS-1FD | on-field hi-vol | 10/03/04 | 0.000988 | 0.00198 | 0.000988 |
| RHS-H2-2FD-100304 | RHS-2FD | on-field hi-vol | 10/03/04 | <0.00295 | 0.00197 | 0.000986 |
| RHS-H2-3FD-100304 | RHS-3FD | on-field hi-vol | 10/03/04 | <0.00295 | <0.00295 | 0.000987 |
| RHS-H2-4FD-100304 | RHS-4FD | upwind hi-vol | 10/03/04 | <0.00284 | <0.00284 | 0.000951 |
| RHS-H2-5FD-100304 | RHS-5FD | far downwind hi-vol | 10/03/04 | <0.00283 | 0.00189 | 0.000947 |
| RHS-L2-1CH-100304 | RHS-1CH | child #1 | 10/03/04 | <0.00298 | <0.00298 | 0.000998 |
| RHS-L2-2CH-100304 | RHS-2CH | child #2 | 10/03/04 | 0.000994 | 0.00398 | 0.000994 |
| RHS-L2-3CH-100304 | RHS-3CH | child #3 | 10/03/04 | 0.000999 | 0.000999 | 0.000999 |
| RHS-L2-4CH-100304 | RHS-4CH | child #4 | 10/03/04 | 0.000996 | 0.000996 | 0.000996 |
| RHS-L2-14CH-100304 | RHS-4CH | duplicate of child #4 | 10/03/04 | 0.000990 | 0.000990 | 0.000990 |
| RHS-L2-5CH-100304 | RHS-5CH | child #5 | 10/03/04 | <0.00296 | 0.00198 | 0.000991 |
| RHS-L2-1NA-100304 | RHS-1NA | non-active adult | 10/03/04 | <0.00298 | <0.00298 | 0.000998 |
| CC2A-L6-1CA-100304 | adult #1 | composite sample collected during the 100304 scenarios | 10/03/04 | 0.000995 | 0.0109 | 0.000995 |
| CC2-L6-1CC-100304 | child #1 | composite sample collected during the 100304 scenarios | 10/03/04 | <0.00292 | 0.00195 | 0.000976 |
| CC2-L6-11CC-100304 | duplicate of child #1 | composite sample collected during the 100304 scenarios | 10/03/04 | 0.000982 | 0.00295 | 0.000982 |
| CC2-L6-2CC-100304 | child #2 | composite sample collected during the 100304 scenarios | 10/03/04 | <0.00298 | <0.00298 | 0.000996 |
| CC2-L6-3CC-100304 | child #3 | composite sample collected during the 100304 scenarios | 10/03/04 | 0.00393 | 0.0108 | 0.000982 |
| CC2-L6-4CC-100304 | child #4 | composite sample collected during the 100304 scenarios | 10/03/04 | 0.00300 | 0.0150 | 0.000999 |
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PCME fibers = fibers longer than 5 microns with a width between 0.25 and 3 microns, and an aspect ratio (length to width) greater than 3:1 AHERA-like total structures = structures longer than 0.5 microns with an aspect ratio greater than 3:1 (Note this differs somewhat from the strict AHERA structure definition) Sensitivity = the sample-specific lowest concentration of asbestos the laboratory can reliably detect s/cc = structures per cubic centimeter |
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The START conducted activity-based outdoor air sampling during the basketball scenario according to the following scripted schedule:
- For the entire 2-hour scenario, one member of the sampling team simulated the activities of an adult/parent spectator sitting near the edge or walking around and occasionally within the area of play. This member of the sampling team would sometimes retrieve a ball that bounced out of the area of play. The intake for the air collection filter cassette worn by this sampling team member was set at a height of about 5 feet.
- For the first 10 minutes, two other members of the sampling team used brooms to sweep the half-court, two dribbled basketballs around the half-court, and one walked close by those sweeping or dribbling. The intakes for the air collection filter cassettes worn by these sampling team members were set at a height of about 3 feet.
- For the remaining 110 minutes, these five other members of the sampling team played basketball and conducted practice drills according to the following 10-minute activity modules:
- Layups
- Top of the Key
- Half-Court Game
- Foul Line Shots
- Layups
- Top of the Key
- Half-Court Game
- Foul Line Shots
- Layups
- Top of the Key
Free Shots
The area within which the START conducted the activity is outlined and the positions of the stationary air sample pumps operating during the basketball scenario are shown as RHB-1FD, RHB2FD, RHB-3FD, RHB-4FD, and RHB-5FD on Figure 5-8 (Rolling Hills Middle School Activity-Based Outdoor Air Sampling Locations–Basketball Scenario). The position of the mobile meteorological station is shown as RHB-MS. A summary of results for the basketball scenario samples is shown in Table 5-11 (Rolling Hills Middle School Basketball Scenario Air Sample Summary Results). See Appendix B for a summary of the results from dust monitoring during this scenario.
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