In compliance
with the Bay Area Air Quality Management District (BAAQMD), Environmental
Protection Agency (EPA) and San Francisco Department of Public Health (SFDPH)
requirements, the CSI site perimeter has been monitored on a daily basis for
each work shift since the demolition/earthwork began. The air
monitors are gathering real time data for PM-10 dust (10 micrometer dust
particulates) and collecting Asbestos air samples (TEM Method for Asbestos
Structures greater than 0.5 micron). USF, has contracted with an
independent Industrial Hygiene firm to perform the perimeter air monitoring on
a daily basis in compliance with the Federal, State and Local requirements.
Results for TEM and PM-10 samples are received by the University generally
24-36 hours after the samples are taken from the job site.
This information supplements the Daily Site Perimeter Air
Monitoring findings reported . The
purpose of the perimeter air monitoring systems is to determine if the
mitigation measures are performing as designed.
It is determined that the perimeter air monitoring system is performing
in exactly the manner in which was intended.
To the extent the air monitoring system has disclosed results that
exceed the prescribed action level, the following cause and results have been
determined. The elevated readings referred
herein refer to TEM only and not PM-10 results.
June 28
|
July 6
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July 12
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July 14
|
July 15
|
Elevated readings at all monitors except #6
|
Elevated readings at all monitors except #1 & #4
|
Elevated reading only at monitor #1
|
Elevated reading at all monitors except #6
|
Elevated levels at monitors #5 & #6
|
Over 1” of rain
|
Very foggy & windy
|
Very foggy/light rain
|
Very windy
|
Very windy
|
Dig/Off Haul SW corner
|
Light activity due to archaeology outside of serpentine
zone
|
Empty trucks entering site from other sites
|
AVAR drilling at south side
|
AVAR drilling at south side
|
Elevated readings at many other SF locations due to
weather
|
|
|
Activity very close to existing monitor location
|
Activity very close to existing monitor location
|
|
|
|
Activity sprays process water into vicinity inside site
|
Activity sprays process water into vicinity inside site
|
At this time BAAQMD has not prescribed alternative action or
required cessation of operations. To the
extent that results exceed the prescribed action levels on June 28 and July 6
they are due to ambient weather conditions and not operations. To the extent additional mitigation is
warranted during excavation activities, they will be implemented by the project. With respect to the results reported for the
July 12 this was likely caused by a contaminated truck entering the site. As in the past, truck tires and under carriage
are wetted down at the site to mitigate airborne particulate matter.
Results reported for July 14 and 15 are attributed to
tieback drilling operations on the south side, extreme winds and inappropriate
monitor location(s) too close to the work operation. For the limited additional operations of the
same or similar to this work, the operation will be modified and additionally
controlled to eliminate elevated reading levels.
