Section 503.40 - Applicability(a) This subpart applies to a person who fires sewage sludge in a sewage sludge incinerator, to a sewage sludge incinerator, and to sewage sludge fired in a sewage sludge incinerator.(b) This subpart applies to the exit gas from a sewage sludge incinerator stack.(c) The management practice in § 503.45(a) , the frequency of monitoring requirement for total hydrocarbon concentration in § 503.46(b) and the recordkeeping requirements for total hydrocarbon concentration in § 503.47(c) and (n) do not apply if the following conditions are met:(1) The exit gas from a sewage sludge incinerator stack is monitored continuously for carbon monoxide.(2) The monthly average concentration of carbon monoxide in the exit gas from a sewage sludge incinerator stack, corrected for zero percent moisture and to seven percent oxygen, does not exceed 100 parts per million on a volumetric basis.(3) The person who fires sewage sludge in a sewage sludge incinerator retains the following information for five years: (i) The carbon monoxide concentrations in the exit gas; and(ii) A calibration and maintenance log for the instrument used to measure the carbon monoxide concentration.(4) Class I sludge management facilities, POTWs (as defined in 40 CFR 501.2 ) with a design flow rate equal to or greater than one million gallons per day, and POTWs that serve a population of 10,000 people or greater submit the monthly average carbon monoxide concentrations in the exit gas to the permitting authority on February 19 of each year.58 FR 9387, Feb. 19, 1993, as amended at 59 FR 9099, Feb. 25, 1994