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What to do when your Hydrocarbon Plume is migrating?

Scenario: You own, manage, rent, or have an investment in a gasoline service station. It makes money for you, or maybe not. A subsurface assessment is performed during a due diligence investigation either initiated by a loan request, possible property buyer, or a third party eyeing your station as a possible adverse environmental condition that could impact their nearby property. The assessment encounters contaminated groundwater and off to the TCEQ races.

Skip to the future and the groundwater sample results from most of the 4, 5 ,6 monitoring wells on/adjacent your service station are showing stable or decreasing levels of contamination. Your Environmental Consultant (EC) informs you that you are almost done – you say hurray – no more sampling events, TCEQ letters, EC bills. Just two more sampling events.

After the EC’s two more quarterly groundwater sampling events, the EC prepares a request for site closure to the TCEQ. About 45 days later, the TCEQ says the contaminant plume has shifted downgradient and the downgradient well now contains the highest concentration of contaminants. The TCEQ requests that you install two more monitoring wells to re-delineate the mobilized contaminant plume. It is possible that those wells have to be placed outside of your property boundaries complicating things. And don’t forget the new costs.

What can be done? We are unable to provide all the answers because they are property/condition specific but here are a few tips:

1- Request that the EC attempt to build a case for TCEQ closure as soon as permitted- usually one to to years of groundwater monitoring. No head in the sand approach is good.

2-Negotitate with the TCEQ like suggesting the use of temporary wells on older plumes instead of permanent wells to get a quick look to see if the plume has moved to that location. Additionally some of the more stable monitoring wells may not have to be continually sampled saving time and funds.

3- Help your case by making sure there are no water leaks or additional UST or sump fuel releases making the situation worse or driving the plume off-site

4- Call Terrain Solutions, Inc. and let us explore possible solutions before you migrate over a financial waterfall.