(a) By-product hydrogen streams and end box ventilation system vents.

(1) For all by-product hydrogen streams and all end box ventilation system vents, if applicable, you must demonstrate continuous compliance with the applicable mercury emission limit by reducing the mercury emissions data to 52-week averages using Equation 1 of §63.8243 and maintaining the 52-week average mercury emissions no higher than the applicable mercury emissions limit in §63.8190(a)(2). To obtain the data to calculate these 52-week averages, you must monitor in accordance with paragraph (a)(1)(i) or (ii) of this section.

(i) Continuous monitoring option. You must collect mercury emissions data according to §63.8244(a), representing at least 75 percent of the 15-minute periods in each operating day of the 52-week compliance period (with data recorded during monitoring malfunctions, associated repairs, and required quality assurance or control activities not counting toward the 75 percent requirement);

(ii) Periodic monitoring option. You must conduct at least three test runs per week to collect mercury emissions samples according to §63.8244(b)(1) and (2)(i) and, if your final control device is not a nonregenerable carbon adsorber, you must collect data for monitoring values according to §63.8244(b)(2)(ii) through (v).

(2) You must maintain records of mercury emissions and 52-week average values, as required in §63.8256(b)(3) and (4). If your final control device is not a nonregenerable carbon adsorber, you must maintain records according to §63.8256(d).

(b) Mercury thermal recovery unit vents.

(1) For each mercury thermal recovery unit vent, you must demonstrate continuous compliance with the applicable emission limit specified in §63.8190(a)(3) by maintaining the outlet mercury hourly-average concentration no higher than the applicable limit. To determine the outlet mercury concentration, you must monitor according to paragraph (b)(1)(i) or (ii) of this section.

(i) Continuous monitoring option. You must collect mercury concentration data according to §63.8244(a), representing at least 75 percent of the 15-minute periods in the operating day (with data recorded during monitoring malfunctions, associated repairs, and required quality assurance or control activities not counting toward the 75 percent requirement).

(ii) Periodic monitoring option. You must conduct at least three test runs per week to collect mercury emissions samples according to §63.8244(b)(1) and (2)(i) and, if your final control device is not a nonregenerable carbon adsorber, you must collect data for monitoring values according to §63.8244(b)(2)(ii) through (v).

(2) You must maintain records of mercury emissions and daily average values as required in §63.8256(b)(3). If your final control device is not a nonregenerable carbon adsorber, you must maintain records according to §63.8256(d).

(c) You must demonstrate continuous compliance with the applicable work practice standards in §63.8192 by maintaining records in accordance with §63.8256(c).