(a) You must conduct each performance test in Table 2 to this subpart that applies to you, as specified in paragraphs (b) through (f) of this section.

(b) You must conduct performance tests under such conditions as the Administrator specifies, based on representative performance of the affected source for the period being tested, and under the specific conditions that this subpart specifies in Table 2 to this subpart and in paragraphs (b)(1) through (4) of this section. You must record the process information that is necessary to document operating conditions during the test and include in such record an explanation to support that such conditions represent normal operation. Upon request, you must make available to the Administrator such records as may be necessary to determine the conditions of performance tests.

(1) You must conduct each performance test concurrently with brew ethanol monitoring to establish a brew-to-exhaust correlation as specified in paragraph (e) of this section.

(2) For each fermentation stage, you must conduct one run of the EPA Test Method 25A of 40 CFR part 60, appendix A-7, over the entire length of a batch. The three fermentation stages do not have to be from the same production run.

(3) You must obtain your test sample at a point in the exhaust-gas stream before you inject any dilution air. For fermenters, dilution air is any air not needed to control fermentation.

(4) You must record the results of the test for each fermentation stage.

(c) You may not conduct performance tests during periods of malfunction.

(d) You must collect data to correlate the brew ethanol concentration to the VOC concentration in the fermenter exhaust according to paragraphs (d)(1) through (3) of this section.

(1) You must collect a separate set of brew ethanol concentration data for each fed-batch fermentation stage while manufacturing the product that constitutes the largest percentage (by mass) of average annual production.

(2) You must measure brew ethanol as specified in § 63.2164 concurrently with conducting a performance test for VOC in fermenter exhaust as specified in paragraph (b) of this section. You must measure brew ethanol at least once during each successive 30-minute period over the entire period of the performance test for VOC in fermenter exhaust.

(3) You must keep a record of the brew ethanol concentration data for each fermentation stage over the period of EPA Test Method 25A of 40 CFR part 60, appendix A-7, performance test.

(e) For each set of data that you collected under paragraphs (b) and (d) of this section, you must perform a linear regression of brew ethanol concentration (percent) on VOC fermenter exhaust concentration (parts per million by volume (ppmv) measured as propane). You must ensure the correlation between the brew ethanol concentration, as measured by the brew ethanol monitor, and the VOC fermenter exhaust concentration, as measured by EPA Test Method 25A of 40 CFR part 60, appendix A-7, is linear with a correlation coefficient of at least 0.90.

(f) You must calculate the VOC concentration in the fermenter exhaust for each batch using the brew ethanol concentration data according to Equation 1 of this section, and using the constants (CF and y) calculated by the applicable linear regression performed under paragraph (e) of this section.

Where: BAVOC = Batch-average concentration of VOC in fermenter exhaust (ppmv measured as propane), calculated for compliance demonstration BAE = Batch-average concentration of brew ethanol in fermenter liquid (percent), measured by the brew ethanol monitor CF = Constant established at performance test and representing the slope of the regression line y = Constant established at performance test and representing the y-intercept of the regression line