July 2020

Afternoon Dust Mitigation Workgroup!

I had an opportunity to take photos of both concrete plans. I compare Superior v Vulcan in the attached document. Here is a preliminary list of recommendations for control measures and air quality based on what I saw. What do folks think?

1) There should be an action level that requires dust mitigation -  a rolling 15-minute PM10 average above 100 micrograms/cubic meter.
2) Cover conveyor belt (Picture 2)
3) Eliminate dust escapes from the mixture. Vulcan mixer has several dust escape routes (Picture 4).
4) Cover concrete dust pile (Picture 6)
5) Add thatched protective property 12-feet fencing (Picture 8)
6) Install camera to cover full conveyor belt activity (Picture 10-12)
7) Install truck rinse area and drainage systems to prevent runoff into community and river (Picture 13-14)
8) More signage needed on dumping, schedule for spraying, definitions of events that trigger spraying. (Picture 15-16)
9) Implement a schedule for spraying and definition of events that trigger spraying.
10) Provide real-time access to "upset reports" that provide self-monitoring data
11) Include provisions in agreement that require after-hours monitoring and compliance
12) Publicly disclose locations of on-site particulate monitors and provide evidence of recording activity

Sincerely,

Chris