BTEX is crude oil's lightest aromatic compound
just one benzene ring
BTEX and PAH known to be carcinogenic, mutagenic, teratogenic.
2004-2007 data to court: capture this, enumerate
Ecuador standard was 1000ppm; levels up to 900 000ppm
the findings found very few BTEX and PAH: they did not exist in virtually all the soil and water samples
The corporations were able to say there was no risk on this basis
Degradation: BTEX is extremely volatile, dissipating from oil quickly, evaporating; can dissolve in water or evaporate
Chevron is correct when it says that the tests demonstrate the virtual absence of BTEX...
"There is no single criterion" for toxicity; the assessment is not based on science of human health risk; "standards may be overly conservative and costly"
The TPH group reviewed data and developed an approach to calculating risk based screening levels
quantifiable level of health protection
>> very comprehensive work
1990s + oil scientists promoted the TPH work >> transformed how hydrocarbon sites are understood
Need for scientific analysis
Gross TPH regulation >> mid 2000s not one US state regulates re: a TPH measure, they use the fractions
new cleanup standards based on dividing hydrocarbons into 13 fractions
The light aromatic hydrocarbons dissipate and biodegrade; heavy PAH's remain in the environment but they are inert: this has been the TPH and industry line
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