We provide a wide range of subsurface environmental investigation services for fuel or chemical release characterization and risk assessment services in close coordination with overseeing regulatory agencies, property owners and stakeholders. The sections below discuss the areas of subsurface investigation that Weber, Hayes and Associates has expertise.
Characterization of Chemical/Fuel Releases
Once a fuel or chemical release is discovered and the appropriate regulatory agencies become involved, characterizing the magnitude and extent of the release such that health risk pathways can be assessed and potential mitigation and/or a remediation strategies can be devised, is typically the next step. Characterization involves advancing subsurface borings to collect environmental sample media (i.e., soil, groundwater and soil vapor) for laboratory chemical analysis, assessment of the geology and hydrogeology across a property, and developing a Conceptual Site Model that completely evaluates the nature and extent of the contaminant release. Site characterization may also include the installation of groundwater and soil vapor monitoring wells to evaluate groundwater flow direction and contaminant concentrations in these media over time, and indoor air sampling to evaluate whether vapor forming chemicals in the subsurface may be migrating at unacceptable concentrations into occupied buildings. Other means of site characterization can involve cone penetrometer testing (CPT) for real-time interpretation of subsurface materials and groundwater bearing zones, and membrane interface probing (MIP) / modeling to create a 3D visualization of the extent of chemical impacts.
Vapor Intrusion Studies
Vapor intrusion, or the accumulation of vapor forming chemicals in the subsurface migrating into occupied structures, has become an increasing concern in recent decades. Â As a result, new policies and guidelines for assessing and mitigating vapor intrusion have emerged over the last decade. Â Weber, Hayes and Associates has conducted numerous vapor intrusion studies at contaminated sites to investigate the indoor air exposure risk from subsurface chemical contamination and through industry advances in the understanding of vapor intrusion has successfully implemented a variety of engineered and non-engineered mitigation techniques that allow for safe occupation of affected building spaces.
Risk Assessment
For some fuel and chemical release investigations, a regulatory agency may require a Site Specific Risk Assessment (SSRA) be completed to evaluate the various pathways by which chemical contamination may impact “sensitive receptors”. Â In lay mans terms, sensitive receptors are humans using a facility or property, natural elements in the environment that require protection (for instance rivers, creeks and wetlands), water supply wells and other sensitive features in the vicinity of a release. Â These assessments are completed in conjunction with an environmental chemist skilled at evaluating risk potentials and pathways for various types of receptors, using modeling to provide risk levels for the respective receptors. Â Weber, Hayes and Associates completes many SSRAs for petroleum, solvent, metal and chemical releases where a more thorough evaluation of risk pathways is required.
In addition, SSRAs are also completed on a voluntary basis, either for voluntary cleanups, redevelopment of “brownsfield” sites, or because a responsible party wishes to provide evidence regarding the most significant high-risk areas of a complex cleanup site.
Underground Storage Tank Removals & Commercial/Industrial Facility Closures
Two standard issues that arise during property transactions or redevelopment of commercial and industrial sites are the removal and “closing” of former fuel or chemical underground storage tanks (USTs) and facility closure reports for hazardous materials storage.
- UST Closures: When USTs are discovered during property transaction or redevelopment, the local regulatory agency in charge usually requires either permitted closure in place or removal of the tank(s), proper disposal of the contents, sampling beneath the tanks to evaluate for a potential release and a report documenting the observations, sample analytical results and recommendations by a registered geologist or engineer. Weber, Hayes and Associates has completed many UST closures, including for bulk fuel facilities, and larger industrial operations involving large excavations and tank arrays.
- Facility Closures for Hazardous Materials Management: When a commercial/industrial business operation such as an automotive repair facility or dry cleaners that manages hazardous materials and wastes closes its doors, the local regulatory agency in charge of hazardous materials oversight often require Facility Closure Reports in order to document the former uses and materials and their proper removal or disposal. This is conducted to draw a line in the sand between one business entity managing hazardous materials and the next land-use at a given property. Weber, Hayes and Associates has completed many facility closure plans and reports to the satisfaction of regulatory agencies and assisted the former business in obtaining closure.
Regulatory Interfacing and Funding Coordination
Our team, which includes registered professional staff that have been with the firm for over two to three decades, strives to maintain good communication and relationships with the various levels of regulatory agencies involved in chemical release investigations. We have experience dealing with chemical release cases that have multiple levels of local, state and federal oversight, including interfacing with the US EPA on Superfund sites. In addition, we work hard to keep our clients and the respective regulators in good standing and find that costs are often minimized by maintaining good relations with regulators.
As is generally the case, contaminant releases are not planned for and certainly not desirable. Considering that the costs associated with release assessment and remedial work is generally not planned for and difficult to insure, various levels of state and federal government have assembled public funding assistance programs to ensure that releases are cleaned up in a timely fashion and that human health and environmental safety is protected. There are various grant sources available to assist with funding a petroleum or hazardous materials release. For more information of specific funding source options, please see Resources » Funding.
