Soil Vapor & Groundwater Assessments
EE&G has conducted soil and groundwater assessments for a variety of contaminants ranging from fuels and oils to solvents and acids. Using a wide range of environmental technologies, our seasoned field technicians and highly qualified scientists ensure that the work is done correctly. It is our goal to collect the data necessary to characterize the site during the initial assessment and tackle the problem immediately. If any unexpected conditions should arise, we have the available resources necessary to adapt and modify the scope of services while the work is in progress, which results in significant savings for our clients. No matter the class of contaminants, we have the capabilities necessary to quickly identify and delineate the affected area.
Aquifer testing and groundwater modeling may be integrated to provide a comprehensive site characterization and to facilitate remediation. Our interpretation of such data allows us to make recommendations on the most efficient and cost-effective alternatives for environmental restoration. Environmental impact measurement techniques have become increasingly sophisticated, requiring specialty services to assess such issues.
The process by which volatile chemicals and hazardous substances contaminate the indoor air quality of homes and buildings is known as “soil vapor intrusion”. Soil vapor also referred to as soil gas, is the air found in the pore spaces between soil particles. Primarily because of a difference between interior and exterior pressures, soil vapor enters a building through cracks or perforations in slabs or basement floors and walls. It also enters through openings around sump pumps or where pipes and electrical wires travel through the foundation. For example, heating, ventilation or air-conditioning (HVAC) systems and/or the operation of large mechanical appliances (e.g., exhaust fans, dryers, etc.) may create a negative pressure that draws soil vapor into the building. This intrusion is similar to how radon gas enters buildings from the subsurface.
Chemicals are a part of our everyday life. They are found in the household products we use and in items we bring into our homes daily. Consequently, there are chemicals found in the indoor air of homes that are not affected by the intrusion of contaminated soil vapor, but by the purchase of everyday household items. Certain commercial and industrial facilities, such as gasoline stations, dry cleaners, and vehicle exhaust are examples of possible sources of volatile chemicals in the outdoor air that can enter homes or businesses.
Vapor Intrusion Studies
Chemicals used in commercial industries sometimes spill or leak into the soil and groundwater. These chemicals, known as volatile organic compounds (VOCs), often become gases or vapors, which can travel from contaminated groundwater and soil into homes and buildings. The migration of VOCs from the subsurface to indoor air is known as vapor intrusion. At sites where volatile, hazardous substances are present in the subsurface, buildings in the occupied vicinity are at risk of contamination.
Since no two sites are exactly alike, the approach to evaluating soil vapor intrusion is dependent upon site-specific conditions. EE&G uses a thorough understanding of the site, including its history of use, characteristics such as geology, geography, identified environmental contamination, etc. and potentially exposed populations to develop an investigation plan. Existing information is reviewed to determine what data are available and what additional data must be collected. In addition, factors affecting soil vapor migration and intrusion and indoor air quality are considered when investigating and evaluating the results. EE&G also considers all information known about the site when determining what actions are appropriate to mitigate current or prevent future human exposures.
Vapor intrusion studies are an evolving science. Over time, as sites continue to be assessed nationwide, our understanding of the relationship between subsurface contamination and indoor air impacts is improving. This will enable us to better predict the degree of vapor intrusion impact on any given building, and estimate the contribution of vapor intrusion to indoor air contaminant measurements.
Regulatory Compliance Audits
A compliance audit is a comprehensive review of an organization’s adherence to regulatory guidelines. Audit reports produced by EE&G include a list of action items and recommendations that the client can use to achieve compliance with applicable environmental regulations. Each assessment takes into consideration the client’s intended use of the site, the site’s location as it relates to other industrial uses, jurisdictional requirements and the client’s risk tolerance. Each assessment is tailor-made for each site to delineate the extent of contamination, identify the contaminants and compare them to regulatory standards.