News and Events
Talk to a Local – The Importance of Local Consultant Knowledge
Local knowledge of project conditions, regulatory programs, and state or regional laws is important when performing environmental consulting services for our clients. Terracon has an advantage in this area over many of our competitors as we have more than 140 offices throughout the country and experts in almost every state that are aware of local issues, regulations, and programs.
Using environmental consultants who have knowledge of local regulations and conditions can be critical to our clients. We have seen several instances when a client has used an out-of-state consultant for a local project, only to have them come back to us for help because of our knowledge of local issues – knowledge the other consultant didn’t have.
During one such instance, a client hired an out-of-state consultant to perform a Phase I Environmental Site Assessment (ESA) for a property acquisition in South Carolina.
The Phase I ESA identified the possible former presence of an underground storage tank. In response, the client hired the same firm to conduct follow-up Phase II sampling, even though the consultant had limited local experience. After the consultant’s groundwater sampling was complete, the client learned that the state of South Carolina requires that groundwater sampling be pre-approved by the state and that subsequent sample results be submitted to state agencies. Because the site owner had not met these requirements, they asked Terracon for technical advice and later hired our Columbia, S.C., office to resolve the issue.
During another situation in Wisconsin, a client hired an out-of-state consultant to perform a Phase I ESA for a strip mall in Madison. The consultant identified dry cleaner operations in the strip mall and performed a Phase II ESA that identified low concentrations of tetrachloroethene (a.k.a. perchloroethene, PCE, or “perc”) in one soil sample. The consultant concluded that “No Further Action” was required and the client proceeded to purchase the strip mall in 2004.
In 2013, Terracon performed a Phase I ESA for a prospective purchaser of a portion of the same strip mall. We were provided the prior Phase I ESA and Phase II reports; however, our Phase I ESA concluded that while the prior Phase I ESA work was done well, the Phase II scope did not investigate inside the building near the dry cleaning machine, where impacts from dry cleaning operations are often worst.
Terracon also did not agree with the previous consultant’s conclusion that No Further Action
was required for the site. The out-of-state consultant did not know that the State of Wisconsin requires all releases be reported. Terracon further noted it was likely that, once notified of the presence of PCE in soil, the State of Wisconsin would likely have required further investigation.
Terracon recommended that the PCE in soil data be reported to the State, which subsequently required additional investigation of the current property owner. This additional investigation identified that PCE had not only contaminated the soil, but also impacted groundwater and possibly indoor air quality. Because of all of these issues, the building owner incurred significant additional costs for investigation and may also sustain future remediation costs.
As if all of this wasn’t enough to make the client regret using a consultant unfamiliar with Wisconsin laws and programs, things became even worse. Because the PCE release was not reported until 2013, the property owner missed a golden opportunity to have all investigation and remediation costs paid by the state (minus a $10,000 deductible) under Wisconsin’s Dry Cleaner Environmental Response Fund (DERF), which stopped accepting applicants in August 2008.
In addition to the awareness of local issues, regulations, and programs, knowledge of local conditions related to natural resources is also important according to Kent Wheeler, P.G., and regional manager of the IHI/Terracon office in Salt Lake City, Utah.
“Local knowledge of geologic conditions is very important when performing Phase I ESAs,” Wheeler said. “Historic lakebed areas have the potential for methane issues, but the issue may not always be called out in a Phase I ESA, due to the non-scope nature of methane.”
In northern Utah, a prehistoric lakebed (Lake Bonneville) once covered most of Utah and parts of Idaho and Nevada. The ancient Lake Bonneville lakebed created large flat areas that are easy to develop; however, many of these areas are also underlain by rich organic deposits that create methane. These methane deposits can create hazards that should be addressed during construction and beyond on a long-term basis.
“Almost no out-of-area consultants and only a few local consultants are aware of these problems,” Wheeler said. “Manholes, basements, and elevator shafts are particularly vulnerable. In some areas, the subsurface is so saturated with methane that water will bubble and catch fire. In addition, several workers have been injured due to the accumulation of this naturally occurring gas.”
On a large regional mall development project, IHI/Terracon was retained by a large national big box retailer because we had identified a methane issue in their Phase I ESA (as a non-scope issue) and had developed systems for both the investigation and mitigation of the problem. IHI/Terracon quickly conducted a site investigation and found very high levels around the entire site. A mobile soil vapor extraction (SVE) system was developed and used along with ongoing monitoring and clearance of all subgrade work. No injuries occurred during the construction process.
To mitigate any future hazards posed by the methane to the facility, IHI/Terracon developed a passive venting system that used the subgrade dewatering system. Ongoing monitoring has shown the effectiveness of the passive venting system. This system has been used at several other facilities across northern Utah.
There are some great environmental consulting firms out there, but few of them have the geographic footprint and local expertise that Terracon has. We’ve worked with a number of clients over the years as a result of solving issues that other consultants just didn’t have the local knowledge to do. Our clients need to know what to do and appreciate it when we have the answers for them.