GSI – not a TV show but perhaps the biggest impediment to closure

4 May 2010

Many property owners have sought closure only to be told by the  MDEQ  “no” because of three little letters – G-S-I.   Ground-water surface water interface (GSI) is Michigan’s own standard to protect surface water from contaminated groundwater.  This is not the same as discharge standards from a pipe that requires permitting.  Michigan has calculated estimated standards for both soil and groundwater designed to protect surface water if the chemicals migrate that far.   Often, the MDNRE’s acceptable levels of contaminants are much more stringent than State and federal drinking standards.

This is an important concept, particularly in Michigan.  However, as with many concepts, our friends at the MDNRE have taken it a bit too far.  Now, closure is as hard as it ever was because there is an assumption that every contaminant will reach surface water, that enclosed storm sewers are somehow “surface water” and that one cannot evaluate the GSI at the actual point of interface – it must be done upland.  All of these requirements have made it nearly impossible to achieve closure when one or more contaminants are present that exceed the State GSI standard regardless of whether surface water is actually being impacted.

I have been working with the Michigan and Detroit Chambers of Commerce on this and other issues which the Legislature is reviewing in Senate Bill 437.  Hopefully, we will see some moderation and common sense applied to protect that which needs protecting and regulation of that which needs regulating without treating all sites exactly the same regardless of their circumstances.  Reasonable risk management must be the MDNRE’s watchword.  Contact your legislator.

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