A multistory office building was being constructed on a former manufacturing site in the harbor area of downtown Baltimore. The site had a significant amount of hexavalent chromium waste, contained a below a surface cap that would need to be disturbed as part of constructing the substructure of the building. This construction site is adjacent to many commercial buildings, residential neighborhoods, marinas, and roadways in this urban setting. There was strong concern in the community that the construction would release dust into the air, creating human health risks. In addition, state and federal regulators were concerned about the environmental impact of the construction and had brought significant oversight to the project. The U.S. Environmental Protection Agency (EPA) wanted an effective and efficient way to measure potential emissions in real-time from the construction work area and the perimeter of the site to ensure that any potential release of dust would be controlled. The site was located on the water and was subject to fog and erratic winds typical of many shoreline properties. To complicate matters, there were many other sources of particulate emissions in this downtown area not related to the construction site.
Emilcott Technologies provided six fixed air monitoring stations - four around the site perimeter, one at the National Aquarium entrance, and another at a city fire station located some distance from the site. An additional eight mobile air monitoring stations were placed daily within the jobsite at active construction operations, soil storage piles and other locations that could potentially generate dust. Each monitoring station was equipped with a particulate monitor to measure dust levels at various particle sizes. All the monitoring stations were designed to operate automatically and be monitored remotely. Data from all the stations were integrated as part of the Greenlight Environmental Monitoring System™ with one full weather station and two wind speed and direction sensors to accurately measure the varying wind flows impacting the site. The results were streamed live to project personnel and the EPA. The air sampling system also sent out alerts and notifications. The data collected by the Greenlight™ system provided evidence this construction project could be conducted safely, without negatively impacting the surrounding community.
Our perimeter air monitoring system operated 24 hours a day, seven days a week for over 9 months with a 97% uptime. High dust results not associated with the construction project were effectively identified and thus did not force shutting down of the construction activities. Dust threshold levels were automatically adjusted upwards when humidity levels exceeded 75%, and the levels of the fixed air monitoring system could be adjusted automatically to compensate for upwind background particulate levels coming from off-site.