(a) You must monitor and collect data according to this section.

(b) Except for, as appropriate, monitor malfunctions, associated repairs, and required quality assurance or control activities (including, as applicable, calibration checks and required zero and span adjustments), you must conduct all monitoring in continuous operation at all times that the process unit is operating. For purposes of calculating data averages, you must not use data recorded during monitoring malfunctions, associated repairs, out-of-control periods, or required quality assurance or control activities. You must use all the data collected during all other periods in assessing compliance. A monitoring malfunction is any sudden, infrequent, not reasonably preventable failure of the monitoring to provide valid data. Monitoring failures that are caused in part by poor maintenance or careless operation are not malfunctions. Any period for which the monitoring system is out-of-control and data are not available for required calculations constitutes a deviation from the monitoring requirements.

(c) You may not use data recorded during monitoring malfunctions, associated repairs, and required quality assurance or control activities or data recorded during periods of safety-related shutdown, pressurized refiner startup or shutdown, startup and shutdown of direct-fired softwood veneer dryer gas-fired burners, or control device downtime covered in any approved routine control device maintenance exemption in data averages and calculations used to report emission or operating levels, nor may such data be used in fulfilling a minimum data availability requirement, if applicable. You must use all the data collected during all other periods in assessing the operation of the control system.

(d) Except as provided in paragraph (e) of this section, determine the 3-hour block average of all recorded readings, calculated after every 3 hours of operation as the average of the evenly spaced recorded readings in the previous 3 operating hours (excluding periods described in paragraphs (b) and (c) of this section).

(e) For dry rotary dryer and veneer predryer wood moisture monitoring, dry rotary dryer temperature monitoring, biofilter bed temperature monitoring, biofilter outlet THC monitoring, and continuous opacity monitoring, determine the 24-hour block average of all recorded readings, calculated after every 24 hours of operation as the average of the evenly spaced recorded readings in the previous 24 operating hours (excluding periods described in paragraphs (b) and (c) of this section).

(f) To calculate the data averages for each 3-hour or 24-hour averaging period, you must have at least 75 percent of the required recorded readings for that period using only recorded readings that are based on valid data (i.e., not from periods described in paragraphs (b) and (c) of this section).

(g) The requirements in paragraphs (c) through (f) of this section do not apply for monitoring the usage of process unit bypass stacks or combustion unit bypass stacks as such monitoring must be conducted continuously at all times that the process unit or combustion unit (that routinely direct-fires a PCWP dryer or lumber kiln) is operating. You must record the dates and times when each bypass stack is used and use the recording readings (excluding invalid data described in paragraph (b) of this section) to calculate and report the total duration of bypass stack usage during the semiannual reporting period.

(h) For lumber kilns, the following temperature data averaging requirements apply:

(1) Temperature limit and hybrid options. You must continuously monitor and record the dry bulb temperature during the kiln drying cycle and record the dry bulb temperature at least once every 15 minutes as specified in § 63.2269(m). The readings from multiple dry bulb temperature monitors positioned to determine the temperature of the heated air that exits the lumber may be averaged together to determine the kiln-wide, dry bulb temperature.

(i) For batch kilns, calculate the average from the recorded readings during each batch cycle, and maintain the batch cycle average dry bulb temperature at or below the maximum temperature limits specified in either § 63.2241(e)(3)(i) or (ii), whichever applies.

(ii) For continuous dry kilns, calculate the daily block average from the recorded readings and maintain the daily block average dry bulb temperature at or below the maximum temperature limits specified in either § 63.2241(e)(3)(i) or (ii), whichever applies.

(2) Site specific plan option. You must continuously monitor the temperature parameter (such as wet or dry bulb temperature, wet bulb depression, or temperature drop across the load) specified in your site-specific plan. You must record the temperature parameter at least every 15 minutes and calculate the 3-hour block average for comparison to the site-specific temperature limit.

(i) For lumber kilns using the hybrid option, the following lumber moisture data averaging requirements must be followed:

(1) Using the lumber moisture content measurement data collected according to § 63.2269(n), calculate and record the semiannual average kiln-dried lumber moisture content for lumber with a given moisture specification produced at the facility.

(2) Compare the semiannual average lumber moisture content for each moisture specification produced at the facility to the applicable minimum kiln-dried moisture content limits included in table 11 to this subpart to determine compliance.

(j) For lumber kilns using the site-specific option, the following lumber moisture data averaging requirements must be followed:

(1) Using the lumber moisture content measurement data collected, calculate and record the monthly and semiannual average kiln-dried lumber moisture content.

(2) Compare the monthly average lumber moisture content to the minimum kiln-dried lumber moisture content limit included in the site-specific plan based on § 63.2241(e)(4) and table 11 to this subpart. You must take corrective action if the monthly average lumber moisture content determined in paragraph (j)(1) of this section is below the minimum lumber moisture content limit in the site-specific plan. You must maintain records of corrective actions taken and report corrective actions in the semiannual report.

(3) Compare the semiannual average kiln-dried lumber moisture content to the minimum lumber moisture content limit included in the site-specific plan based on § 63.2241(e)(4) of this section and table 11 to this subpart to determine compliance.

(k) If you observe opacity using EPA Method 9 of appendix A-4 to part 60 of this chapter (in conjunction with pressure drop monitoring) instead of using a COMS for mechanical collectors (or other dry control device not listed elsewhere in table 2 to this subpart) to meet a compliance option in table 1D or 1E to this subpart, you must follow the procedure for demonstrating continuous compliance with the opacity observation limit in paragraphs (k)(1) and (2) of this section.

(1) A qualified observer must conduct two weekly 6-minute opacity observations of the mechanical collector (or other dry control device) exhaust to the atmosphere according to EPA Method 9 of appendix A-4 in part 60 of this chapter and 40 CFR 60.11 to demonstrate the opacity remains below the maximum limit established according to § 63.2262(u).

(2) If the average of the two weekly 6-minute opacity observations exceeds the maximum opacity limit established in paragraph (k)(1) of this section, you must take appropriate corrective action to correct the above normal emissions as soon as practicable and within the monitoring period and record the action taken.