Wednesday, April 10, 2019


Three points today plus I'm holding another in reserve. First non detects in soil and sediment reports often assign a value of 50% of the method detection limit. Thus if you are giving a result for 2,4 DDD + 4,4 DDE and the value for 2,4 DDE is 24 ppb and the value for 4,4 DDE is ND(20.0) ppb then the result would be 24 + 10 = 34 parts per billion (ppb). That is the norm. In this 2019 report however all non detects are assigned a value of zero which is nonsense with such a high detection limit and with the DDT compounds (DDD, DDE DDT) being ubiquitous throughout the Canagagigue Creek.

The Severe Effect Level (SEL) criteria being used in the tables on pages 19 through 24 I believe are incorrect. The values in the tables stating the numbers of exceedances of the SEL do not match up with the highest concentrations found and reported in the table for each individual compound. In other words if the SEL is 6,000 ppb and the table reports ten exceedances with the highest concentration found being only 230 ppb you can see the discrepancy. The other possible error is that instead of exceedances of the SEL being reported they may have reported exceedances of the PEL (probable effect level) which is a much smaller number than the SEL. Clearly explanations are needed yet with the general public being denied the right to either ask questions or make comments at RAC and TAG meetings then the authors of these inadequate reports are mostly unaccountable.

Joe Kelly of TAG did raise a very important point at the March 2019 TAG meeting. He advised that only 24 sediment samples were taken in the creek by the generally accepted Core method which is a tube pushed into the bottom of the Creek which fills with the sediments in the bottom of the Creek and then brings them to the surface for examination and testing. The alternate less acceptable method is the shovel method and it was used 338 times to capture sediments. That method however does not retain the sediments (especially the fines?) nearly as well as the Core method and indeed the MOE (MECP) were critical of that methodology.

Tomorrow at 5 pm. in council chambers, the RAC committee will discuss the March 2019 Creek report. My guess is that even with some criticism from two TAG members the report will be accepted with minimal discussion and explanation and one more step in the inadequate investigation and remediation of the Creek will be completed.

1 comment:

  1. Without a doubt on the report acceptance statement in your last paragraph. Also how nice Joe Kelley mentions the same thing I commented on a long time ago from my sediment experience regarding riverine sampling. I was glad yesterday you acknowledged that even professionals that are currently working would not be able to seriously look at the report time wise like you can do. Consulting is a very high pressure profession to deliver the results in a timely manner at a reasonable cost to the client. You would never be able to do what you do if employed by them.