Code of Maine Rules › 06 - DEPARTMENT OF ENVIRONMENTAL PROTECTION › 096 - DEPARTMENT OF ENVIRONMENTAL PROTECTION - GENERAL › Chapter 117 - SOURCE SURVEILLANCE - EMISSIONS MONITORING › Section 096-117-3 - Performance Specifications for Continuous Emissions Monitoring Systems

Current through 2024-29, July 17, 2024
A. The source owner or operator shall operate
				the CEMS and record accurate data in the units of the applicable standard
				during all source operating times, except for periods when the CEMS is subject
				to established quality assurance and quality control procedures or during
				periods of unavoidable malfunction. Any emissions data collected during periods
				when an emissions unit is not operating, shall not be used in determining
				compliance with any emission limit.
B. Any CEMS installed pursuant to this
				Chapter shall meet the performance specifications set forth in 40 CFR Part 60,
				Appendix B, 40 CFR Part 75 and comply with applicable specifications and
				provisions of 40 CFR Part 60, Appendix B, regarding monitor location,
				calibration and interpretation of results. Data used for calculating excess
				emissions shall not include data substitution using the missing data procedures
				of 40 CFR Part 75; nor shall the data have been bias adjusted according to the
				procedures of 40 CFR Part 75. Missing data shall be reported as downtime for
				the purposes of this Chapter.
C.
				For a CEMS installed pursuant to this Chapter, the following minimum
				specifications apply unless otherwise specified by federal regulation.
(1) The minimum specifications described in
				40 CFR Part 60, Appendix B are incorporated herein by reference.
(2) A CERMS or gaseous CEMS shall record and
				report valid data as follows:
(a) A CEMS must
				complete a minimum of one cycle of operation (sampling, analyzing and data
				recording) for each of the four successive 15-minute quadrants of the hour
				(starting at the top of the clock hour), except during hours where scheduled QA
				is being performed. A minimum of one data point in at least three of the four
				distinct 15-minute quadrants constitutes a valid hour. During periods of
				scheduled QA a minimum of one data point in at least two of the four distinct
				15-minute quadrants constitutes a valid hour.
(b) A gaseous CEMS and CERMS must average and
				record the data in a manner consistent with the applicable emission standard.
				Data need not be recorded for a particular time period if the emissions unit
				did not operate during that time period.
(i)
				A three-hour block average will be considered valid if it contains at least 2
				valid hourly averages.
(ii) A
				four-hour block average will be considered valid if it contains at least 3
				valid hourly averages.
(iii) A
				six-hour block average will be considered valid if it contains at least 4 valid
				hourly averages.
(iv) A twelve-hour
				block average will be considered valid if it contains at least 9 valid hourly
				averages.
(v) A twenty-four-hour
				average will be considered valid if it contains at least 18 valid hourly
				averages.
(vi) A thirty-day rolling
				average shall be calculated as described in 40 CFR Part 60, Method 19, equation
				19-19. Simply stated that means: the sum of the (valid) block hour values
				monitored for the last 30 emissions unit operating days divided by the sum of
				the number of (valid) block hours monitored for the past 30 emissions unit
				operating days.
(3) A CEMS for measuring opacity, particulate
				matter or gaseous emissions shall have the capability of displaying
				instantaneous values of the appropriate output for use during audits. Audit
				readings should be taken from the normal data recording equipment if
				practical.
(4) A COMS used to
				determine compliance with applicable opacity standards shall average data to
				result in one or six-minute averages (starting at the top of the clock hour),
				as approved by the Department and EPA. A valid six-minute average requires four
				valid minutes of data. A valid minute consists of a minimum of a sample point
				in four of the six distinct 10 (ten) second blocks or 67 percent of the
				minute.
(5) A PM CEMS shall average
				data as approved by the Department and EPA.