Question # 185

185. If a covered facility has a solution containing a chromium compound, does the facility need to report on the entire mixture or just the chromium when making a threshold determination under Section 313?
To determine if a facility meets an applicable threshold for the chromium compound (or any toxic chemical) in a solution, the facility is required to determine the weight percent of chromium compound in the solution and use that amount for the threshold determination (40 CFR Section 372.30(b)).