A knowledgeable reader writes:

"Dear Diane,

...Reading through the various "Environmental Law and Litigation" articles excellently written by your staff, I'm increasingly frustrated by the universal failure throughout the industry to recognize a very serious flaw at the root of environmental site assessments/cleanups and it is one that has serious consequences for all involved, particularly site owners who end up footing the bill. Every site cleanup is fundamentally based on the results of lab analysis of the soil and groundwater. The consultant prepares a sampling plan, drills the site and sends his/her environmental samples to the lab, receives a certificate of analysis and the report is written based on these results. If a cleanup is deemed necessary (based on these results), it includes on-going lab tests and a final report is issued declaring the site "clean", all based on the results from the lab. Any inquiry to the lab about the validity of the results is met with reassurances that proper quality control procedures were used along with MOECC-approved methodologies and these can be seen in the umpteen pages of data included in the lab report following the page with the results. Any inquiry to the consultant about the validity of the results will simply be referred back to the lab along with the assurance that the lab is accredited by CALA. Thus, the flaw remains hidden.

Any inquiry to an analytical chemist trained in sampling statistics would quickly reveal that while the lab procedures are excellent, the lab result may be meaningless because the size of sample being analysed is far too small to represent the site's condition. You simply cannot make the 2 or 3 grams of soil analysed at the lab represent the many millions of grams at the site but this is precisely what we are forced to do on a daily basis under O. Reg 153/04. The problem is not so serious in those areas of a site that are heavily loaded with contaminants but it gets very tricky trying to decide where the contamination runs out as the levels start to approach the very low allowable limits. Actually, it's not tricky, its impossible. I'm very uneasy about my reports that are meant to reassure everyone that a site is "clean" (or "dirty") when I have no idea whether the sample sent to the lab has any relation to the actual site conditions. The solution would be to analyse much larger samples or a vastly greater number of small samples but neither of these is practical so I'm stuck with my fingers crossed hoping no one will later re-examine my sites and find more contaminant in one of their small samples. That will likely lead to a call from their lawyer!

I am now including an explanation in my reports regarding "Data Quality Objectives" which clearly explains the uncertainties involved (attached) but I'm not sure what legal ramifications this creates.

George Duncan"

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