This summer, the New Jersey Department of Environmental Protection (NJDEP) is expected to introduce a long-anticipated guidance document on perimeter air monitoring. The guidance will apply to sites for which an NJDEP spill case has been generated, placing them under regulation of the Contaminated Site Remediation and Redevelopment Program unit (formerly referred to as the Site Remediation Program). A wide variety of activities conducted on these sites—including environmental investigation, remediation, demolition, and construction—have the potential to release contaminants that may migrate through the air beyond the perimeter of the site. For example, brownfield sites in densely populated areas where remedial actions often include excavation and removal of contaminated soil that may cause harmful vapors to be released into the air and negatively impact the surrounding community. At a demolition site, heavy-metal laden dust particulates have potential to migrate off-site and create a similarly negative impact.
Currently, there is no guidance document available to the environmental and Licensed Site Remediation Professional (LSRP) community concerning perimeter air monitoring. Presently, codified regulations amount to just one line in the Technical Requirements for Site Remediation (see N.J.A.C. 7:26E-5.5(b)7). Therefore, the specifics of perimeter air monitoring at brownfield remediation sites are currently at the discretion of the environmental consultant who designs the remedial approach.
Those following perimeter air monitoring developments in the environmental consulting industry anticipate the new requirements to be very prescriptive and detailed—potentially along the lines of the profound changes that were introduced by the NJDEP’s vapor intrusion guidance issued in 2012. We expect similarly well-defined perimeter air monitoring criteria.
Notwithstanding the anticipated guidance document requirements, there are a few “basics” that any environmental practitioner should recognize, and which site owners/responsible parties would also benefit from understanding when perimeter air monitoring is being planned:
Equipment requirements. The proposed monitoring sensors and instruments should be well-matched to the site’s contaminants of concern. Consider the equipment’s power needs: Some models require 110-line power. What are the operations and maintenance needs for the selected equipment? Can the equipment be operated remotely, or does it require on-site personnel?
Monitoring equipment location and weather. Wind is a significant contributor to the off-site migration of contaminants. Therefore, it is important to obtain local or on-site weather data. Before siting other instruments and sensors, consider their placement relative to the Site’s predominant up and down-wind locations, the proximity of the site to nearby receptors, and the neighboring land use (i.e., residential, agricultural, etc.).
Data. A perimeter air monitoring program will produce significant amounts of data. Anticipating how to manage, interpret, and report the data before the program begins is important. Who should have access to the data (contractor, owner, the public)? How should data results be conveyed so they can be easily comprehended by both technical and non-technical stakeholders?
Action levels. It is imperative to understand the point at which conditions being tracked exceed acceptable thresholds, or action levels. Should an exceedance occur, protocols should be established that include: who receives notification; via what method; the appropriate corrective action and by whom; and the acceptable corrective response time. Also, will reporting be conducted continuously and remotely enabling 24/7 notification, or conducted manually at longer intervals?
One reason for the NJDEP’s delay may be that they have been working to integrate the perimeter air monitoring guidance with its recent environmental justice (EJ) regulations, which speak to reducing neighborhood stressors that impact overburdened communities (OBCs). Because brownfields are more frequently found in OBCs, the air quality at these and other sites undergoing remediation is expected to fall under much closer scrutiny than in the past.
Perimeter air monitoring has many components that individuals in the environmental industry and their clients will soon learn to integrate into work at brownfield sites and other projects. Although the NJDEP suggested that the guidance document would have been issued in 2021, and then again in 2022, things do seem to be materializing for its release this year.
Marc Hudock, LSRP, is a Senior Vice President of AirLogics, LLC, which provides comprehensive perimeter air monitoring services. AirLogics is a subsidiary of GZA GeoEnvironmental, Inc.