First of all is it fair to call a compulsive, pathological thief by any such name each and every time they walk into a store? Is it fair to call CRA/GHD intellectual prostitutes each and every time they write an alleged scientific report. I described here a little bit about their latest (Sept. 3, 2026) effort titled "Bench Scale Study for Biodegradation of Chlorobenzene and NDMA" yesterday.
I have confirmed with a past APTE coordinator that we had all been told decades ago by Uniroyal Chemical and their consultants that chlorinated solvents such as trichloroethylene, chloroform, chlorobenzene etc. do not easily degrade or break down on their own in soils. It turns out however that chlorobenzene is the exception to that rule. Now according to this latest report by GHD, chlorobenzene actually degrades very well on its' own in shallower, aerated soils and less so in deeper anaerobic soils as per pages 7 & 8. The Figures section, particularly Figures 1 and 5 also confirms this. This of course speaks very badly of Uniroyal and CRA because the inaccurate information was used to deny chlorobenzene's presence on the Varnicolor Chemical site when zero chlorobenzene was found in Varnicolor's shallow aquifer also known as the Surficial Aquifer (SA).
Other problems exist including the premature thawing of frozen groundwater samples meant to be used in the Bench Scale Biodegradation Study. While I appreciate the admission of this unfortunate incident that occurred at U.S. customs I am less comfortable with GHD proceeding with their experiments using compromised groundwater samples rather than starting over. Another problem might be GHD's repeatedly advising that their Biodegradation Rates may very well be biased on the high side due to possible volatilization of compounds from the groundwater samples. I wonder if this so called volatilization didn't occur and they spiked the samples according to page 3 with 150 ppb. chlorobenzene and 2.4 ppb. NDMA, if their Biodegradation rates might actually be biased on the high side. Either way again I find their protocols surprising and disturbing. It seems to be a vey peculiar way to be conducting scientific experiments. It's almost seems to be a "seat of the pants" scientific protocol. Something goes wrong so instead of really fixing it or starting over they just make a change and continue on.
Assuming for the moment that their experiments have some validity what I conclude is that dissolved chlorobenzene degrades in both aerobic (oxygen) and anaerobic (low oxygen) environments. NDMA on the other hand seems much less capable of degrading via human intervention such as amendments and nutrients both in shallow and deeper soils. Of course as mentioned yesterday chlorobenzene has other characteristics and the issue is not what the dissolved chlorobenzene will do as much as what the Dense Non Aqueous Phase Liquid (DNAPL) chlorobenzene will do. The "Non Aqueous Phase" part of that acronym makes it clear that DNAPLS are NOT dissolved in water chlorobenzene but thicker, heavier pools or puddles probably residing in depressions of lesser permeable soils such as silts and clays. Likely some of these have dissolved over the last thirty years but any claims by Lanxess and fellow travellors that they are fully dissolved is nonsense, wishful thinking and maybe even intellectual prostitution.
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