WVDEP Releases New Corrective Action Guidance Document (CAGD) for Leaking Aboveground Storage Tanks (LAST) and Leaking Underground Storage Tanks (LUST)
On July 25, 2018, the West Virginia Tanks Corrective Action Unit (TCAU) released its update to the Corrective Action Guidance Document (CAGD) for Leaking Aboveground Storage Tanks (LAST) and Leaking Underground Storage Tanks (LUST), which became effective upon publication. The stated intent of the CAGD is to better articulate West Virginia’s LAST/LUST program requirements, provide clarification on what information must be collected when investigating and cleaning up releases, and improve the consistency and quality of required reports, resulting in a more streamlined process for remediating LAST/LUST sites. The guidance discusses the processes and procedures for identifying and investigating suspected and confirmed releases, identifying appropriate cleanup levels, selecting and conducting appropriate corrective actions, and establishing reporting requirements. The CAGD is applicable to regulated Aboveground Storage Tanks (ASTs) as defined by W.Va. Code §22-30 and Underground Storage Tanks (USTs) subject to regulation by W.Va. Code §22-17 and 40 CFR 280. Note that regulated ASTs are either Level 1 or 2.
The CAGD replaces and supersedes previous AST and UST closure guidance documents and incorporates a number of concepts that shift the paradigm of how LAST/LUST sites are investigated and remediated in West Virginia.
First, TCAU has abandoned the use of total petroleum hydrocarbons (TPH)/diesel range organics (DRO)/gasoline range organics (GRO)/oil range organics (ORO) as analytes of interest in favor of individual chemicals most associated with the different TPH ranges. Analysis for TPH will still be performed to profile petroleum-contaminated waste for disposal.
Second, the TCAU has developed three tiers of new action levels for soils at LAST/LUST sites that are protective of direct contact (ingestion, dermal contact, and inhalation of volatile organic compounds/particulates) and vapor intrusion exposure pathways (inhalation of volatile organic compounds). The Tier 1 level is the most conservative of the three tiers and applies to most sites. Tier 2 provides soil action levels for sites under residential use. Tier 3 may be utilized for determining compliance with the soil action levels when the property owner has agreed to place a deed restriction on the property, appropriately restricting its use to non-residential. Tier 2 and 3 action levels are depth-dependent (0 to 8 feet and greater than 8 feet) to protect human health, and their use can be precluded by “limiting factors,” which generally consist of subsurface utilities and building or soil conditions that could result in preferential migration of volatile organic compounds into buildings.
Third, protection of groundwater is addressed entirely through the use of a 10-foot soil buffer. There is an underlying presumption that a 10-foot soil buffer is sufficient to prevent contaminants in soil from leaching into groundwater and causing groundwater contamination irrespective of the concentrations in the soil. Under this approach, if contamination (defined as “detectable”) is detected within 10 vertical feet of the water table, or free product is present at the water table, a groundwater investigation must be conducted. For circumstances where contamination is not detected within 10 vertical feet of the water table, it is presumed that meeting Tier 1, 2, or 3 action levels is protective of groundwater.
In addition to the concepts discussed above, the guidance establishes various quality control procedures related to collecting environmental samples, constructing monitoring wells, and validating laboratory data.
Be advised that the above discussion is a broad-brush synopsis of the primary elements and concepts that comprise the CAGD, and that there are many intricacies and caveats that are part of the CAGD that are not mentioned in this blog post, not the least of which is how keywords such as “soil,” “contamination,” and “product” are defined.
If your company’s operations involve the management and oversight of aboveground or underground storage tanks in West Virginia and you would like to know more about the CAGD update and clarifications, please contact the author, Robert (Bo) Valli, at email@example.com or (412) 303-6699.
CEC has developed a follow-up post on key provisions added to streamline the WV LAST/LUST program. Click the link to read this additional information or paste the following into your browser: https://blog.cecinc.com/2018/08/08/key-provisions-added-to-wv-last-lust-program.