pH Control

[vj2007]

In trying to stabilize large volumes of hydrocarbon impacted soils using varying mixes of cement and quicklime additive, we are running into problems of high pH. If their a remedy to contoll the pH without affeting the suitable TCLP characteristics.

Thanks.

 

[kenvlach]

If high pH is a problem, why are you using quicklime???
Also, you can specify a low alkali cement. Type II is often low alkali, but I think it is an option for most types (except high early strength).

http://www.cement.org/tech/cct_cement_specifying.asp

Re TCLP: are you trying to prevent leaching, or to fudge the the extraction from samples tested per EPA Method 1311? For volatiles, this uses an initial dose of acetic acid-sodium acetate at pH 4.93, but there is no adjustment for alkaline soils (unlike the test method if extracting metals). So, the abnormally high pH may neutralize the acetic acid and reduce the extraction efficiency. Also, abnormally high pH may kill the bacteria that naturally decompose the solvents over time. Maybe not something your local EPA overseer would approve for a remediation plan.

http://www.epa.gov/sw-846/pdfs/1311.pdf