62.14412 What stack opacity and visible emissions requirements apply?

(a) Your HMIWI (regardless of size category) must not discharge into the atmosphere from the stack any gases that exhibit greater than 6 percent opacity (6-minute block average).

(b) Your HMIWI as defined in §62.14400(a)(2)(ii) and utilizing a large HMIWI must not discharge into the atmosphere visible emissions of combustion ash from an ash conveying system (including conveyor transfer points) in excess of 5 percent of the observation period (i.e., 9 minutes per 3-hour period), as determined by EPA Reference Method 22 of 40 CFR part 60, appendix A-7, except as provided in paragraphs (b)(1) and (2) of this section.