The following standards shall apply except as provided in Sections 3(D) and 3(E) of this Chapter:
A.Fuel Burning Equipment. Equipment shall be subject to one of the standards in this section: (1) Boilers Firing #4, #5, or #6 Fuel Oil Boilers firing #4, #5, or #6 fuel oil shall comply with either (a), (b), or (c) below, as applicable: (a) Visible emissions from any unit whose rated input capacity is less than 100 million BTU/hr shall not exceed an opacity of 30 percent on a six (6) minute block average basis, except for periods of startup, shutdown, malfunction, or certain equipment maintenance, during which times the unit operator may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. Eligible equipment maintenance must be specifically identified in the facility's air emission license as subject to work practice standards in this rule.(b) Visible emissions from any unit whose rated input capacity is 100 million BTU/hr or greater shall not exceed an opacity of 20 percent on a six (6) minute block average basis, except for periods of startup, shutdown, malfunction, or certain equipment maintenance, during which times the unit operator may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. Eligible equipment maintenance must be specifically identified in the facility's air emission license as subject to work practice standards in this rule.(c) Visible emissions from any unit whose rated input capacity is 100 million BTU/hr or greater shall not exceed an opacity of 20 percent on a six (6) minute block average basis for 95 percent of all six (6) minute block averages on a quarterly basis. The remaining 5 percent of all six (6) minute block averages on a quarterly basis shall be no greater than 45 percent opacity. Periods of start-up, shutdown and malfunctions are included for the purpose of calculating block averages under this subsection. Periods when the unit is not operating are not included for the purpose of calculating block averages under this subsection. Quarterly basis is the period of time from January 1 to March 31, April 1 to June 30, etc. A unit subject to this subsection shall be required to operate and maintain a COMS. (2) Boilers Firing Distillate Fuel Visible emissions from any unit firing distillate fuel shall not exceed an opacity of 20 percent on a six (6) minute block average basis.
For the purposes of this Chapter, distillate fuel means the following:
(a) Fuel oil that complies with the specifications for fuel oil numbers 1 or 2, as defined by the American Society for Testing and Materials (ASTM) in ASTM D396;(b) Diesel fuel oil numbers 1 or 2, as defined in ASTM D975;(c) Kerosene, as defined in ASTM D3699;(d) Biodiesel, as defined in ASTM D6751; or (e) Biodiesel blends, as defined in ASTM D7467.(3) Boilers Firing Natural Gas or Propane Visible emissions from any unit firing natural gas or propane shall not exceed an opacity of 10 percent on a six (6) minute block average basis.
(4) Stationary Internal Combustion Units Visible emissions from any stationary internal combustion unit (either reciprocating engine or combustion turbine) shall not exceed an opacity of 20 percent on a six (6) minute block average basis.
(a) During periods of startup, the unit operator of a reciprocating engine may elect to comply with the work practice standards of Section 4(B) of this Chapter in lieu of this visible emission standard. (b) During periods of startup, the unit operator of a combustion turbine may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. (5) Boilers Firing Wood /Biomass and Multi-Fuel Boilers Boilers firing wood/biomass and multi-fuel boilers shall comply with either (a) or (b) below: (a) Visible emissions shall not exceed 30 percent opacity on a six (6) minute block average basis, except for periods of startup, shutdown, malfunction, or certain equipment maintenance, during which times the unit operator may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. Eligible equipment maintenance must be specifically identified in the facility's air emission license as subject to work practice standards in this rule. (b) Visible emissions shall not exceed an opacity of 20 percent on a six (6) minute block average basis for 95 percent of all six (6) minute block averages on a quarterly basis. The remaining 5 percent of all six (6) minute block averages on a quarterly basis shall be no greater than 45 percent opacity. Periods of start-up, shutdown and malfunctions are included for the purpose of calculating block averages under this subsection. Periods when the unit is not operating are not included for the purpose of calculating block averages under this subsection. Quarterly basis is the period of time from January 1 to March 31, April 1 to June 30, etc. A unit subject to this subsection shall be required to operate and maintain a COMS. For the purposes of this Chapter, multi-fuel boiler means a boiler which fires more than one type of fuel simultaneously.
(6) Visible emissions from any fuel burning equipment not specifically listed in this section shall not exceed an opacity of 30 percent on a six (6) minute block average basis, except for periods of startup, shutdown, malfunction, or certain equipment maintenance, during which times the unit operator may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. Eligible equipment maintenance must be specifically identified in the facility's air emission license as subject to work practice standards in this rule. For any fuel burning equipment monitored by COMS that is not subject to 40 C.F.R. Part 60, 63, or 75 as amended up to July 1, 2018, the COMS shall record opacity on a six (6) minute block average basis.
B.General Process Sources(1) Visible emissions from any asphalt plant baghouse shall not exceed an opacity of 20 percent on a six (6) minute block average basis, except for periods of startup, shutdown, malfunction, or certain equipment maintenance, during which times the unit operator may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. Eligible equipment maintenance must be specifically identified in the facility's air emission license as subject to work practice standards in this rule.(2) Visible emissions from rock crushers shall not exceed an opacity of 10 percent on a six (6) minute block average basis.(3) Visible emissions from baghouses, excluding asphalt plant baghouses, shall not exceed an opacity of 10 percent on a six (6) minute block average basis. The facility shall take corrective action if visible emissions from the baghouses exceed five (5) percent opacity on a six (6) minute block average basis.(4) Visible emissions from any general process source not specifically listed in this section shall not exceed an opacity of 20 percent on a six (6) minute block average basis.(5) For any general process source monitored by COMS and for which the COMS is not subject to 40 C.F.R. Parts 60 or 63 as amended up to July 1, 2018, the COMS shall record opacity on a six (6) minute block average basis.C.Fugitive Emission Sources Visible emissions from a fugitive emission source shall not exceed an opacity of 20 percent, on a five (5) minute block average basis.
D.Combined Stack EmissionsExcept as provided for in subsection 3(E)(2), visible emissions from two or more of any combination of sources subject to this Chapter which are operating concurrently and emitting air contaminants through one common stack or vent shall comply with either (1) or (2) below. Sources which emit through a common stack subject to this section are subject to the standards applicable to individual sources elsewhere in this Chapter when only one of the sources is in operation.
(1) Visible emissions from a common stack not monitored by a COMS shall not exceed an opacity of 30 percent on a six (6) minute block average basis, except for periods of startup, shutdown, malfunction, or certain equipment maintenance, during which times the unit operator may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. Eligible equipment maintenance must be specifically identified in the facility's air emission license as subject to work practice standards in this rule.(2) Visible emissions from a common stack monitored by a COMS shall not exceed an opacity of 20 percent on a six (6) minute block average basis for 95 percent of all six (6) minute block averages on a quarterly basis. The remaining 5 percent of all six (6) minute block averages on a quarterly basis shall be no greater than 45 percent opacity. Periods of start-up, shutdown and malfunctions are included for the purpose of calculating block averages under this subsection. Periods when the unit is not operating are not included for the purpose of calculating block averages under this subsection. Quarterly basis is the period of time from January 1 to March 31, April 1 to June 30, etc.E.Boilers Restricted to Less than 20 Percent Capacity on an Annual BasisBoilers with a licensed annual capacity limit of 20 percent or less shall comply with either (1), (2), or (3) below:
(1) Visible emissions shall not exceed an opacity of 30 percent on a six (6) minute block average basis, except for periods of startup, shutdown, malfunction, or certain equipment maintenance, during which times the unit operator may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. Eligible equipment maintenance must be specifically identified in the facility's air emission license as subject to work practice standards in this rule.(2) Visible emissions from any source comprised of two or more units emitted through a common stack or vent shall not exceed an opacity of 40 percent on a six (6) minute block average basis, except for periods of startup, shutdown, malfunction, or certain equipment maintenance, during which times the unit operator may elect to comply with the work practice standards of Sections 4(A) or 4(C) of this Chapter in lieu of this visible emission standard. Eligible equipment maintenance must be specifically identified in the facility's air emission license as subject to work practice standards in this Chapter. In order to be subject to this subsection, all units which emit through the common stack must be subject to a 20 percent annual capacity limit.(3) Visible emissions from any stack monitored by a COMS shall not exceed an opacity of 30 percent on a six (6) minute block average basis for 95 percent of all six (6) minute block averages on a quarterly basis. The remaining 5 percent of all six (6) minute block averages on a quarterly basis shall be no greater than 50 percent opacity. Periods of start-up, shutdown and malfunctions are included for the purpose of calculating block averages under this subsection. Periods when the unit is not operating are not included for the purpose of calculating block averages under this subsection. Quarterly basis is the period of time from January 1 to March 31, April 1 to June 30, etc. If two or more units emit through a common stack monitored by a COMS, in order to be subject to this subsection, all units which emit through the common stack must be subject to a 20 percent annual capacity limit.06- 096 C.M.R. ch. 101, § 3