AIR MONITORING RESULTS

Air monitor locations

Week of July 25, 2022

• Note: The follow-up chemical analysis for the July 21-July 25 period detected lead at 0.00022 mg/m3, slightly above the conservative threshold selected for this work site of 0.00015 mg/m3.  This lead detection occurred at meter location 2, which was located close to the active excavation.  Samples for July 21-July 25 were merged to generate sufficient sample volume. There were no exceedances of dust action levels on this day and no exceedances of other chemical action levels at any other perimeter monitors or worker personal monitors.  Actions have been taken to ensure dust is controlled within the work area.

  • It is important to note that the threshold for lead is set very low at this work site to protect the health of the workers and the community, and there is no health risk to the surrounding community. The threshold of 0.00015 mg/m3 currently used at the site is the National Ambient Air Quality Standard for lead and is normally used over a 90-day period. To be extremely protective of health, this project is using this number over a single work day.

Week of July 18, 2022

• Note: The follow-up chemical analysis for the July 21-July 25 period detected lead at 0.00022 mg/m3, slightly above the conservative threshold selected for this work site of 0.00015 mg/m3.  This lead detection occurred at meter location 2, which was located close to the active excavation.  Samples for July 21-July 25 were merged to generate sufficient sample volume. There were no exceedances of dust action levels on this day and no exceedances of other chemical action levels at any other perimeter monitors or worker personal monitors.  Actions have been taken to ensure dust is controlled within the work area.

  • It is important to note that the threshold for lead is set very low at this work site to protect the health of the workers and the community, and there is no health risk to the surrounding community. The threshold of 0.00015 mg/m3 currently used at the site is the National Ambient Air Quality Standard for lead and is normally used over a 90-day period. To be extremely protective of health, this project is using this number over a single work day.

Week of July 11, 2022

• Note: On July 13, 2022, air monitoring station no.1, had a detected level of fibrous material equal to the action level of 0.01 fibers per cubic centimeter (f/cc). The sample was sent for additional TEM analysis. The additional analysis concluded that none of the fibrous material detected was asbestos.  Cellulose was present, suggesting the fibrous material detected contained natural fibers.

Weeks