Methane (CH 4 ) A hydrocarbon that is a greenhouse gas with a global warming
potential most recently estimated at 25 times that of carbon dioxide (CO 2 ).
Methane is produced through anaerobic (without oxygen) decomposition of
waste in landfills, animal digestion, decomposition of animal wastes, production
and distribution of natural gas and petroleum, coal production, and incomplete
fossil fuel combustion. The GWP is from the IPCC’s Fourth Assessment Report
(AR4).
Metric ton Common international measurement for the quantity of greenhouse gas
emissions. A metric ton is equal to 2205 lbs. or 1.1 short tons.
Microorganisms Very small organisms that can be seen only through a microscope. Some microorganisms use the wastes in wastewater for food and thus
remove or alter much of the undesired matter.
Miticide It is a substance that kill mites.
Mitigation (a) A human intervention to reduce the human impact on the climate
system; it includes strategies to reduce greenhouse gas sources and emissions and
enhancing greenhouse gas sinks; (b) Activities taken to reduce the loss of life and
lessen the impact to property from disasters.
Mixed liquor suspended solids (MLSSs) (a) The concentration of suspended
solids present in activated sludge mixed liquor, usually expressed as milligrams
per liter (mg/L); (b) Suspended solids in the mixed liquor of an aeration tank.
Mixed liquor volatile suspended solids (MLVSS) (a) The fraction of the
suspended solids in biological reactor’s mixed liquor that can be burned off by
combustion at 550
C., or the organic portion of the solids (an estimation of the
microorganisms and food). Usually expressed as milligrams per liter (mg/L).
(b) The organic or volatile suspended solids in the mixed liquor of an aeration
tank. This volatile portion is used as a measure or indication of the microorganisms present.
Mixed liquor (ML) (a) The water containing biosolids in a biological reactor.
(b) When the activated sludge in an aeration tank is mixed with primary effluent
or the raw wastewater and return sludge, this mixture is then referred to as mixed
liquor as long as it is in the aeration tank. Mixed liquor may also refer to the
contents of mixed aerobic or anaerobic digesters.
Mixed wastes The entire volume of any waste mixture containing a listed hazardous waste, regardless of concentration, is considered a hazardous waste with the
following exceptions: (a) the listed waste in the mixture was listed solely because
it exhibits a hazardous waste characteristic and the mixture no longer exhibits that
characteristic; (b) a wastewater discharge subject to regulation by the Clean
Water Act (CWA) and the hazardous waste mixed with the mixtures of
nonhazardous wastes and characteristic hazardous wastes if the mixture no longer
exhibits any of the characteristics (ignitability, corrosivity, reactivity, and toxicity); (c) a wastewater discharge subject to regulation by the Clean Water Act
(CWA) and the hazardous waste mixed with the waste water which concentration
of carcinogenic and non-carcinogenic spent solvents listed in 40 CFR Part 261.31
in the wastewater, provided the concentration does not exceed 1 ppm and 25 ppm,
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465
potential most recently estimated at 25 times that of carbon dioxide (CO 2 ).
Methane is produced through anaerobic (without oxygen) decomposition of
waste in landfills, animal digestion, decomposition of animal wastes, production
and distribution of natural gas and petroleum, coal production, and incomplete
fossil fuel combustion. The GWP is from the IPCC’s Fourth Assessment Report
(AR4).
Metric ton Common international measurement for the quantity of greenhouse gas
emissions. A metric ton is equal to 2205 lbs. or 1.1 short tons.
Microorganisms Very small organisms that can be seen only through a microscope. Some microorganisms use the wastes in wastewater for food and thus
remove or alter much of the undesired matter.
Miticide It is a substance that kill mites.
Mitigation (a) A human intervention to reduce the human impact on the climate
system; it includes strategies to reduce greenhouse gas sources and emissions and
enhancing greenhouse gas sinks; (b) Activities taken to reduce the loss of life and
lessen the impact to property from disasters.
Mixed liquor suspended solids (MLSSs) (a) The concentration of suspended
solids present in activated sludge mixed liquor, usually expressed as milligrams
per liter (mg/L); (b) Suspended solids in the mixed liquor of an aeration tank.
Mixed liquor volatile suspended solids (MLVSS) (a) The fraction of the
suspended solids in biological reactor’s mixed liquor that can be burned off by
combustion at 550
C., or the organic portion of the solids (an estimation of the
microorganisms and food). Usually expressed as milligrams per liter (mg/L).
(b) The organic or volatile suspended solids in the mixed liquor of an aeration
tank. This volatile portion is used as a measure or indication of the microorganisms present.
Mixed liquor (ML) (a) The water containing biosolids in a biological reactor.
(b) When the activated sludge in an aeration tank is mixed with primary effluent
or the raw wastewater and return sludge, this mixture is then referred to as mixed
liquor as long as it is in the aeration tank. Mixed liquor may also refer to the
contents of mixed aerobic or anaerobic digesters.
Mixed wastes The entire volume of any waste mixture containing a listed hazardous waste, regardless of concentration, is considered a hazardous waste with the
following exceptions: (a) the listed waste in the mixture was listed solely because
it exhibits a hazardous waste characteristic and the mixture no longer exhibits that
characteristic; (b) a wastewater discharge subject to regulation by the Clean
Water Act (CWA) and the hazardous waste mixed with the mixtures of
nonhazardous wastes and characteristic hazardous wastes if the mixture no longer
exhibits any of the characteristics (ignitability, corrosivity, reactivity, and toxicity); (c) a wastewater discharge subject to regulation by the Clean Water Act
(CWA) and the hazardous waste mixed with the waste water which concentration
of carcinogenic and non-carcinogenic spent solvents listed in 40 CFR Part 261.31
in the wastewater, provided the concentration does not exceed 1 ppm and 25 ppm,
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465