Attachment G-5a RulemakingLanguageUMRTables

Table 1

Missing Data Procedures for Hg CEMS

Trigger conditions

Calculation routines

Monitor data availability (percent)	Duration (N) of CEMS outage (hours)	Method	Look back period
90 or more	N < 24	Average	hour before/hour after
	N > 24	Greater of average or 90^th percentile	hour before/hour after
> 80 but < 90	N < 8	Average	hour before/hour after
	N > 8	Greater of average or 95^th percentile	720 hours*
> 70 but < 80	N > 0	Maximum value**	720 hours*
Below 70	N > 0	Maximum potential concentration or %	None

* Quality-assured, monitor operating hours, during unit operation. Use data from no earlier than 3 years prior to the missing data period.

** Where a unit with add-on Hg emission controls can demonstrate that the controls are operating properly, as provided in 40 CFR 75.34, the unit may, upon approval, use the maximum controlled emission rate from the previous 720 operating hours.

Table 2

Quality Assurance/Quality Control Criteria for Sorbent Trap Monitoring Systems

QA/QC test or specification	Acceptance criteria	Frequency	Consequences if not met
Pre-test leak check…………………..	<4% of target sampling rate..	Prior to sampling…	Sampling shall not commence until the leak check is passed.
Post-test leak check…………………	<4% of average sampling rate..	After sampling……...	Sample invalidated.**
Ratio of stack gas flow rate to sample flow rate……………………………..	Maintain within + 25% of initial ratio from first hour of data collection period.	Every hour throughout data collection period.	Case-by-case evaluation.
Sorbent trap section 2 breakthrough.	≤ 5% of Section 1 Hg mass.........	Every sample.............	Sample invalidated.**
Paired sorbent trap agreement………	<10% Relative Deviation (RD)...	Every sample.............	Sample invalidated.**
Spike recovery study..........................	Average recovery between 85% and 115% for each of the 3 spike concentration levels.	Prior to analyzing field samples and prior to use of new sorbent media.	Field samples shall not be analyzed until the percent recovery criteria has been met.
Multipoint analyzer calibration..........	Each analyzer reading within + 10% of true value and r2 ≥ 0.99.	On the day of analysis, before analyzing any samples.	Recalibrate until successful.
Analysis of independent calibration standard.	Within + 10% of true value.........	Following daily calibration, prior to analyzing field samples.	Recalibrate and repeat independent standard analysis until successful.
Spike recovery from section 3 of sorbent trap.	75–125% of spike amount...........	Every sample.............	Sample invalidated.**
RATA.	RA ≤ 20.0% or mean difference ≤ 1.0 μg/dscm for low emitters.	For initial certification and annually thereafter.	Data from the system are invalidated until a RATA is passed.
Dry gas meter calibration (At 3 orifice initially, and 1 setting thereafter).	Calibration factor (Y) within + 5% of average value from the initial (3-point) calibration.	Prior to initial use and at least quarterly thereafter.	Recalibrate the meter at three orifice settings to determine a new value of Y.
Temperature sensor calibration…......	Absolute temperature measured by sensor within + 1.5% of a reference sensor.	Prior to initial use and at least quarterly thereafter.	Recalibrate. Sensor may not be used until specification is met.
Barometer calibration.........................	Absolute pressure measured by instrument within + 10 mm Hg of reading with a mercury barometer.	Prior to initial use and at least quarterly thereafter.	Recalibrate. Instrument may not be used until specification is met.

And data from the pair of sorbent traps are also invalidated