UST/AST Assessments

The storage of fuels and chemical agents can pose a great risk to the environment. Leaks in storage tanks can be sudden, but in most cases occur for long periods of time and are often unknown to the property owners.  As a result of these risks, most states have promulgated rules pertaining to the registration, installation, maintenance, and removal of underground storage tanks (USTs) and above ground storage tanks (ASTs).

In Ohio, the UST rules are governed by the Department of Commerce, Bureau of Underground Storage Tank Regulations (BUSTR).  These rules pertain to the handling of UST closures and the corrective actions to be taken when leaks are discovered.

The steps involved in the closure/corrective actions can be complex and difficult to navigate through.  The primary steps include:

• Closure Assessment and Sampling – Performed when closing or removing a UST.
• Tier 1 Source Investigation – Performed when contamination is discovered in the ground around the tank.
• Tier 1 Delineation – Activities to determine how far the contamination has spread.
• Tier 2 Evaluation – Initial risk assessment to identify the receptors and develop site specific action levels to protect the receptors.
• Tier 3 Evaluation – Perform complex modeling to develop site specific action levels for the site.

Each of these steps requires detailed and timely reporting.  EES has over 20 years experience in performing corrective actions for UST/AST sites.  From the simpler (closure assessments) to the complex (Tier 3 modeling) activities, EES has a proven track record of obtaining no further action (NFA) decisions for many sites.