Section 6750. Monitoring

A. The provisions governing monitoring shall be as follows:

1. With regard to the emissions standards in 9VAC5-40-6670 A, 9VAC5-40-6680, and 9VAC5-40-6690, the provisions of 9VAC5-40-40 (Monitoring) apply.

2. With regard to the emission limits in 9VAC5-40-6570 through 9VAC5-40-6660 and 9VAC5-40-6670 B, the following provisions apply:

a. 9VAC5-40-40 A and F;

b. 40 CFR 60.13; and

c. Subsections B through L of this section.

B. Continuous emission monitoring systems for gaseous pollutants shall be installed as follows.

1. Each affected municipal waste combustion unit shall install, calibrate, maintain, and operate continuous emission monitoring systems for oxygen (or carbon dioxide), sulfur dioxide, and carbon monoxide. Class I municipal waste combustion units shall also install, calibrate, maintain, and operate a continuous emission monitoring system for nitrogen oxides. The continuous emission monitoring systems for sulfur dioxide, nitrogen oxides, and oxygen (or carbon dioxide) shall be installed at the outlet of the air pollution control device.

2. Each continuous emission monitoring system shall be installed, evaluated, and operated according to the monitoring requirements in 40 CFR 60.13.

3. The oxygen (or carbon dioxide) concentration shall be monitored at each location where sulfur dioxide and carbon monoxide are monitored. Class I units shall also monitor the oxygen (or carbon dioxide) concentration at the location where nitrogen oxides are monitored.

4. Carbon dioxide may be monitored instead of oxygen as a diluent gas. If carbon dioxide is monitored, then an oxygen monitor is not required and the requirements in 9VAC5-40-6750 F shall be met.

5. If compliance is demonstrated by monitoring the percent reduction of sulfur dioxide, continuous emission monitoring systems for sulfur dioxide and oxygen (or carbon dioxide) shall be installed at the inlet of the air pollution control device.

6. If an alternative sulfur dioxide monitoring method is used, such as parametric monitoring, or if the source cannot monitor emissions at the inlet of the air pollution control device to determine percent reduction, an alternative monitoring method may be used on approval of the board under 40 CFR 60.13(i).

C. Continuous emission monitoring systems shall be operated as follows.

1. Initial, daily, quarterly, and annual evaluations of the continuous emission monitoring systems that measure oxygen (or carbon dioxide), sulfur dioxide, nitrogen oxides (Class I units only), and carbon monoxide shall be conducted.

2. The initial evaluation of the continuous emission monitoring systems shall be completed within 180 days after the final compliance date specified in 9VAC5-40-6710 A.

3. For initial and annual evaluations, data shall be collected concurrently (or within 30 to 60 minutes) using the oxygen (or carbon dioxide) continuous emission monitoring system, the sulfur dioxide, nitrogen oxides, or carbon monoxide continuous emission monitoring systems, as appropriate, using the following test methods:

a. For nitrogen oxides as monitored by Class I units, the pollutant concentration levels shall be validated using Reference Method 7, 7A, 7B, 7C, 7D, or 7E; oxygen (or carbon monoxide) shall be measured using Reference Method 3 or 3A.

b. For sulfur dioxide, the pollutant concentration levels shall be validated using Reference Method 6 or 6C; oxygen (or carbon monoxide) shall be measured using Reference Method 3 or 3A.

c. For carbon monoxide, the pollutant concentration levels shall be validated using Reference Method 10, 10A, or 10B; oxygen (or carbon monoxide) shall be measured using Reference Method 3 or 3A.

4. Data shall be collected during each initial and annual evaluation of the continuous emission monitoring systems as follows.

a. For opacity: the span value shall be 100%, and Performance Specification 1 shall be used. Reference Method 9 shall be used if needed to meet minimum data requirements.

b. For nitrogen oxides as monitored by Class I units: the span value for the control device outlet shall be 125% of the maximum expected hourly potential nitrogen oxides emissions of the municipal waste combustion unit, and Performance Standard 2 shall be used. Reference Method 7E shall be used if needed to meet minimum data requirements.

c. For sulfur dioxide:

(1) For the inlet to the control device: the span value shall be 125% of the maximum expected hourly potential sulfur dioxide emissions of the municipal waste combustion unit, and Performance Standard 2 shall be used. Reference Method 6C shall be used if needed to meet minimum data requirements.

(2) For the control device outlet: the span value shall be 50% of the maximum expected hourly potential sulfur dioxide emissions of the municipal waste combustion unit, and Performance Standard 2 shall be used. Reference Method 6C shall be used if needed to meet minimum data requirements.

d. For carbon monoxide: the span value shall be 125% of the maximum expected hourly potential carbon monoxide emissions of the municipal waste combustion unit, and Performance Specification 4A shall be used. Reference Method 10 with alternative interference trap shall be used if needed to meet minimum data requirements.

e. For oxygen or carbon dioxide: the span value shall be 25% oxygen or 25% carbon dioxide, and Performance Specification 3 shall be used. Reference Method 3A or 3B shall be used if needed to meet minimum data requirements.

5. The quality assurance procedures in Procedure 1 of appendix F of 40 CFR Part 60 shall be followed for each continuous emission monitoring system.

D. The accuracy tests for the sulfur dioxide continuous emission monitoring system require evaluation of the oxygen (or carbon dioxide) continuous emission monitoring system. Therefore, the oxygen (or carbon dioxide) continuous emission monitoring system is exempt from Section 2.3 of Performance Specification 3 in appendix B of 40 CFR Part 60 (relative accuracy requirement) and Section 5.1.1 of appendix F of 40 CFR Part 60 (relative accuracy test audit).

E. The following schedule for evaluating continuous emission monitoring systems shall be met.

1. Annual evaluations of the continuous emission monitoring systems shall be conducted no more than 13 months after the previous evaluation was conducted.

2. Continuous emission monitoring systems shall be evaluated daily and quarterly as specified in appendix F of 40 CFR Part 60.

F. The relationship between oxygen and carbon dioxide shall be established during the initial evaluation of the continuous emission monitoring systems, and may be reestablished during annual evaluations. The relationship shall be established as follows.

1. Reference Method 3A or 3B shall be used to determine oxygen concentration at the location of the carbon dioxide monitor.

2. At least three test runs for oxygen shall be conducted. Each test run shall represent a one-hour average, and sampling shall continue for at least 30 minutes in each hour.

3. The fuel-factor equation in Reference Method 3B shall be used to determine the relationship between oxygen and carbon dioxide.

G. The following monitoring data shall be collected.

1. Where continuous emission monitoring systems are required, one-hour arithmetic averages shall be obtained. The averages for sulfur dioxide, nitrogen oxides (Class I units only), and carbon monoxide shall be in parts per million by dry volume at 7.0% oxygen (or the equivalent carbon dioxide level). The one-hour averages of oxygen (or carbon dioxide) data from the continuous emission monitoring system shall be used to determine the actual oxygen (or carbon dioxide) level and to calculate emissions at 7.0% oxygen (or the equivalent carbon dioxide level).

2. At least two data points per hour shall be obtained in order to calculate a valid one-hour arithmetic average. 40 CFR 60.13(e)(2) requires the continuous emission monitoring systems to complete at least one cycle of operation (sampling, analyzing, and data recording) for each 15-minute period.

3. Valid one-hour averages shall be obtained for 75% of the operating hours per day for 90% of the operating days per calendar quarter. An operating day is any day the unit combusts any municipal solid waste or refuse-derived fuel.

4. Failure to obtain the minimum data required in subdivisions G 1 through 3 of this section constitutes a violation of the data collection requirement regardless of the emission level monitored. In such case the board shall be notified according to 9VAC5-40-6770 B 2 e.

5. If the minimum data required in subdivisions G 1 through 3 of this section is not obtained, the owner shall nevertheless use all valid data from the continuous emission monitoring systems in calculating emission concentrations and percent reductions in accordance with subsection H of this section.

H. One-hour arithmetic averages shall be converted into averaging times and units as follows.

1. Emissions shall be calculated at 7.0% oxygen using the following equation:

C_7%=C_unc*(13.9)*(1/(20.9–CO₂))

where:

C_7% = concentration corrected to 7.0% oxygen.

C_unc = uncorrected pollutant concentration.

CO₂ = concentration of oxygen (percent).

2. Reference Method 19 shall be used to calculate the daily geometric average concentrations of sulfur dioxide emissions. Owners monitoring the percent reduction of sulfur dioxide shall use Reference Method 19 to determine the daily geometric average percent reduction of potential sulfur dioxide emissions.

3. Class I units shall use Reference Method 19 to calculate the daily arithmetic average for concentrations of nitrogen oxides.

4. Reference Method 19 shall be used to calculate the four-hour or 24-hour daily block averages (as applicable) for concentrations of carbon monoxide.

I. Operating parameters required for continuous monitoring are as follows.

1. Municipal waste combustion unit load shall be monitored as follows:

a. Municipal waste combustion units that generate steam shall install, calibrate, maintain, and operate a steam flowmeter or a feed water flowmeter as follows.

(1) The measurements of steam (or feed water) shall be continuously measured and recorded in kilograms (or pounds) per hour.

(2) The steam (or feed water) flow shall be calculated in four-hour block averages.

(3) The steam (or feed water) flow rate shall be calculated using the method in "American Society of Mechanical Engineers Power Test Codes: Test Code for Steam Generating Units, Power Test Code 4.1—1964 (R1991)," section 4 (see 9VAC5-20-21).

(4) Nozzles or orifices for flow rate measurements shall be designed, constructed, installed, calibrated, and used following the recommendations in "American Society of Mechanical Engineers Interim Supplement 19.5 on Instruments and Apparatus: Application, Part II of Fluid Meters," 6th Edition (1971), chapter 4 (see 9VAC5-20-21).

(5) Before each dioxins/furans emission test, or at least once a year, all signal conversion elements associated with steam (or feed water) flow measurements shall be calibrated according to the manufacturer's instructions.

b. If the municipal waste combustion units do not generate steam, or if the municipal waste combustion units have shared steam systems and steam load cannot be estimated per unit, the owner shall determine, to the satisfaction of the board, one or more operating parameters that can be used to continuously estimate load level (for example, the feed rate of municipal solid waste or refuse-derived fuel). The selected parameters shall be monitored continuously.

2. The owner shall install, calibrate, maintain, and operate a device to continuously measure the temperature of the flue gas stream at the inlet of each particulate matter control device.

3. Municipal waste combustion units that use activated carbon to control dioxins/furans or mercury emissions shall perform the following.

a. A carbon injection system operating parameter that can be used to calculate carbon feed rate (for example, screw feeder speed) shall be selected.

b. During each dioxins/furans and mercury emission test, the average carbon feed rate in kilograms (or pounds) per hour and the average operating parameter level that correlates to the carbon feed rate shall be determined. A relationship between the operating parameter and the carbon feed rate in order to calculate the carbon feed rate based on the operating parameter level shall be established.

c. The selected operating parameter shall be continuously monitored during all periods when the municipal waste combustion unit is operating and combusting waste, and the eight-hour block average carbon feed rate shall be calculated in kilograms (or pounds) per hour, based on the selected operating parameter. When calculating the eight-hour block average, (i) hours when the municipal waste combustion unit is not operating shall be excluded, and (ii) hours when the municipal waste combustion unit is operating but the carbon feed system is not working correctly shall be included.

4. Continuous parameter monitoring systems shall meet the following requirements.

a. One-hour arithmetic averages shall be obtained for the following parameters:

(1) Load level of the municipal waste combustion unit;

(2) Temperature of the flue gases at the inlet of the particulate matter control device; and

(3) Carbon feed rate if activated carbon is used to control dioxins/furans or mercury emissions.

b. In order to calculate a valid one-hour arithmetic average, at least two data points per hour shall be obtained.

c. Valid one-hour averages shall be obtained for at least 75% of the operating hours per day for 90% of the operating days per calendar quarter. An operating day is any day the unit combusts any municipal solid waste or refuse-derived fuel.

d. If the minimum data required in subdivisions 4 a through c of this subsection are not obtained, the owner is in violation of the data collection requirement, and shall notify the board according to 9VAC5-40-6770 B 2 e.

J. An initial evaluation of the continuous opacity monitoring system shall be completed according to Performance Specification 1 in appendix B of 40 CFR Part 60 no later than 180 days after the final compliance date specified in 9VAC5-40-6710 A. Each annual evaluation of the continuous opacity monitoring system shall be completed no more than 13 months after the previous evaluation. Tests shall be conducted according to Reference Method 9, as specified in 9VAC5-40-6740 D, to determine compliance with the opacity limit in 9VAC5-40-6660. The data obtained from the continuous opacity monitoring system are not used to determine compliance with the opacity limit.

K. Operation of the continuous emission monitoring systems and continuous opacity monitoring system shall use the required span values and applicable performance specifications in 9VAC5-40-6750 C.

L. If any continuous emission monitoring systems are temporarily unavailable to meet the data collection requirements due to systems malfunction or when repairs, calibration checks, or zero and span checks prevent collection of the minimum amount of data, the alternate methods found in 9VAC5-40-6740 D shall be used.

Historical Notes

Derived from Volume 19, Issue 24, eff. September 10, 2003.

Statutory Authority

§ 10.1-1308 of the Code of Virginia.