Administrative Procedure Act: The Administrative Procedure Act governs all legal challenges to a permit under State law once the Department has issued its Final Determination. The Act is found under Title 10 of the State Government Article of the Annotated Code of Maryland.
Administrative Order: Under COMAR, an “administrative order" means a written notification issued by the Department under State law and regulations, and requiring correction of a water pollution condition or compliance with the provisions of pertinent laws and regulations.1
Administrative Record: The written and/or recorded record of all proceedings on the administrative level, beginning with the informational meeting on a proposed permit, permit reissuance, permit modification or permit revocation.
Aerobic: Bacteria that require oxygen to live; used for decomposition of organic wastes.
Ambient: The natural existing condition of a waterway unaffected by a discharge.
Anaerobic: Organisms that do not require oxygen to survive.
Anti-backsliding: A provision of the Clean Water Act that prohibits a permit from being less stringent than the prior permit except in certain enumerated circumstances.2
Anti-degradation: A rule or policy required by the Clean Water Act stating, in part, that existing water quality uses be maintained and protected whether or not those uses are being attained.3
Assimilative Capacity: The ability of a body of water to absorb a pollutant without adverse effect on humans, aquatic life or wildlife.
Average Monthly Discharge Limit: The highest allowable average of daily discharges over a calendar month, calculated as the sum of all daily discharges measured during that month divided by the number of days on which monitoring was performed (except in the case of fecal coliform).4
Average Weekly Discharge Limit: The highest allowable average of daily discharges over a calendar week, calculated as the sum of all daily discharges measured during a calendar week divided by the number of daily discharges measured during that week.5
Base flow: The flow in a stream without taking into account surface runoff; the natural surface flow originating from groundwater.6
Bioassay: A test used to evaluate the relative potency of a chemical or a mixture of chemicals by comparing its effect on a living organism with the effect of a standard preparation on the same organism.7
Biochemical Oxygen Demand (BOD): A measurement of the amount of oxygen utilized by the decomposition of organic material, over a specified time period (usually 5 days) in a wastewater sample; it is used as a measurement of the readily decomposable organic content of wastewater.8
Biological Treatment: The use of bacteria to destroy organic waste.
Biological Monitoring: Under the Clean Water Act, the term “biological monitoring” shall mean the determination of the effects on aquatic life, including accumulation of pollutants in tissue, in receiving waters due to the discharge of pollutants (A) by techniques and procedures, including sampling of organisms representative of appropriate levels of the food chain appropriate to the volume and the physical, chemical, and biological characteristics of the effluent, and (B) at appropriate frequencies and locations.9
Bioremediation: The use of living organisms to remove pollutants from water or wastewater.
Bypass: The intentional diversion of a wastestream from any portion of a treatment or pretreatment facility; permissible under very limited circumstances delineated in the permit. (Not the same as an Upset).
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Code of Federal Regulations (CFR): The Federal Regulations based on the Environmental Protection Agency’s interpretation of the Clean Water Act; certain sections are directly applicable to state permits. Before a federal regulation is finalized, it is published in the Federal register and is open for public comment. The CFR is updated and republished annually and is on-line to the public. The Environmental Regulations are found in Title 40.
Chemical Oxygen Demand (COD): A measure of the oxygen-consuming capacity of the inorganic and organic matter present in wastewater. COD is expressed as the amount of oxygen consumed in mg/l. Results do not necessarily correlate to the biochemical oxygen demand (BOD) because the chemical oxidant may react with substances that bacteria do not stabilize.10
Code of Maryland Regulations (COMAR): Maryland regulations based upon Maryland law and the applicable provisions of the Clean Water Act.
Combined Sewer Overflow (CSO): The discharge of untreated wastewater from a combined sewer system at a point prior to the headworks of a publicly owned treatment works.11 CSOs result from an overload of sewage and stormwater collected in a combined sewer system (CSS). Overflows are not permissible during dry weather.
Comment Period: See public comment period.
Compliance: The ability of a permittee to meet all terms and conditions of a permit. If the permitee is out of compliance, an enforcement action may be brought to establish a compliance schedule, assess fines and penalties or take other affirmative remedial action, including criminal sanctions.
Compliance Schedule: A schedule of remedial measures included in a permit or an enforcement order, including a sequence of interim requirements (for example, actions, operations or milestone events) that lead to compliance with the Clean Water Act and regulations.12
Composite Sample: A series of water samples taken over a specified period of time to determine the representative sample over that time period.
Consent Decree: A legal document formalizing an agreement between the permittee and the Department requiring the permittee to take certain actions to comply with the permit.
Continuous Discharge: A discharge that flows from a wastewater pipe into the receiving stream on a 24 hour basis.
Conventional Pollutants: Conventional pollutants defined under the Clean Water Act are: biochemical oxygen demand, total suspended solids, pH, fecal coliform, and oil and grease.13 All other pollutants are classified as non-conventional pollutants.
Criteria (narrative): Descriptive surface water quality standards stated in narrative terms (without specific numeric limits); for instance, a discharge may not "create a nuisance."14
Criteria (numeric): Surface water quality criteria with specific numeric limits for each pollutant.15
Cumulative Effect: The effect of a discharge on the environment taking into consideration all environmental factors in their totality.
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Daily Maximum Limit: The maximum allowable discharge of a pollutant during a calendar day. Where daily maximum limits are expressed in units of mass, the daily discharge is the total mass discharged over the course of the day. Where daily maximum limitations are expressed in terms of concentration, the daily discharge is the arithmetic average measurement of the pollutant concentration derived from all measurements taken that day.16
Dechlorination: The process of removing chlorine from the waste stream so that no residual chlorine is discharged into the receiving waters.
Department: Maryland Department of the Environment.
Design Flow: The number of gallons of flow a wastewater treatment plant is engineered to accommodate on a daily basis.
Designated Use: Those uses specified in the State's water quality standards for each water body or segment whether or not the uses are being attained.17 Each use has particular and specific water quality standards applied to it.
Discharge: Under the Clean Water Act, the term “discharge of a pollutant” and the term “discharge of pollutants” each means (A) any addition of any pollutant to navigable waters from a point source, (B) any addition of any pollutant to the waters of a contiguous zone or the ocean from any point source other than a vessel or other floating craft.18
Discharge Monitoring Report (DMR): The self-monitoring report filled out by NPDES permittees and sent to the Department as a part of permit compliance.
Dissolved Oxygen (DO): DO is the amount of oxygen available in water for the survival of aquatic life. Wastewater permits require that the discharge contain sufficient dissolved oxygen to prevent harm to aquatic life.
Draft Permit: A document prepared under 40 CFR 124.6 indicating the Director’s tentative decision to issue, deny, modify, revoke and reissue, terminate, or reissue a permit. A notice of intent to terminate a permit, and a notice of intent to deny a permit application, as discussed in 40 CFR 124.5 are considered draft permits. A denial of a request for modification, revocation and reissuance, or termination, as discussed in 40 CFR 124.5, is not a draft permit.19
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Effluent: Wastewater that is discharged into the receiving stream.20
Effluent Limitation: Under the Clean Water Act, the term “effluent limitation” means any restriction established by the State or the Administrator on quantities, rates, and concentrations of chemical, physical, biological, and other constituents which are discharged from point sources into navigable waters, the waters of a contiguous zone, or the ocean, including schedules of compliance.21
End of Pipe: A phrase used to determine a measuring point for effluent testing. It refers to the final point of discharge before the effluent enters the receiving water.
Enforcement: Any legal action taken to bring a permittee into compliance.
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Fact Sheet: A document that must be prepared for all draft individual permits for NPDES major dischargers, NPDES general permits, NPDES permits that contain variances, NPDES permits that contain sewage sludge land application plans and several other classes of permittees. The document summarizes the principal facts and the significant factual, legal, methodological and policy questions considered in preparing the draft permit and tells how the public may comment (40 CFR 128.4 and 124.56). Where the fact sheet is not required, a statement of basis must be prepared (40 CFR 124.7).22
Fecal Coliform: Under COMAR, fecal coliform means the portion of the coliform bacteria group which is present in the gut or the feces of warm-blooded animals.23
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Gallons per day (GPD): The amount of flow that passes through the wastewater treatment plant on a daily basis; usually measured as millions of gallons per day (MGD). One million gallons per day is shown as 1.0 mgd; one half million gallons per day is shown as 0.5 mgd.
Grab Sample: A single sample taken within a specified period of time. A grad sample is representative of the water quality at the time the sample is taken but is not representative of what is occurring over time.
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Influent: Wastewater flowing into the treatment plant prior to treatment.
Informational Hearing: A hearing held, upon request of a member of the public, to discuss terms and conditions of a pending permit application.24
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Major Facility: a wastewater treatment plant with a discharge flow greater than one million gallons per day.
MGD-see gallons per day.
Minor Facility: A wastewater treatment plant with a discharge flow of less than one million gallons per day.
Mitigation: An act or action taken to reduce an adverse impact on the environment.
Mixing Zone: An area where an effluent discharge undergoes initial dilution and is extended to cover secondary mixing in the ambient water body. A mixing zone is an allocated impact zone where water quality criteria can be exceeded as long as acute toxic conditions are prevented.25
Modification (major and minor): A change in the permit requested by the permittee or the Department at a point in time when the permit is not up for renewal. Only the requested issue may be reopened. Modifications are major (and open to the public participation process) or minor (and not subject to the public participation process) depending upon the change sought.26
Most Probable Number (MPN): A statistical estimate of the level of coliform bacteria in a water sample based upon density per 100 milliliters.
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National Pollution Discharge Elimination System (NPDES): The system under the Clean Water Act that required permitting for discharge of pollutants into the waters.
Non-Conventional Pollutant: A water pollutant not listed as a conventional pollutant, toxic pollutant or thermal discharge under the Clean Water Act.
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Organic: Carbon-containing materials derived from living organisms.
Operation and Maintenance (O & M): Actions taken or plans implemented to assure that a wastewater treatment plant will operate in compliance with its permit.
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Point Source: Any discernible, confined, and discrete conveyance including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fixture, container, rolling stock, concentrated animal feeding operation, landfill leacheate collection system, vessel, or other floating craft from which pollutants are or may be discharged.27
Pollutant: Under the Clean Water Act the term “pollutant” means dredged spoil, solid waste, incinerator residue, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt, and industrial, municipal, and agricultural waste discharged into the water.28
pH: The numeric measure of the acidity or alkalinity of water. A pH of 7.0 is considered neutral.
Pollution: Under the Clean Water Act, the term “pollution” means the man-made or man-induced alteration of the chemical, physical, biological, and radiological integrity of water.29
Potable Water: Water that is safe for human consumption.
Pretreatment: The reduction of pollutants from industrial or other waste streams before the waste can be discharged into a publicly owned wastewater treatment plant.30
Primary Treatment: The first step in wastewater treatment where the solids and floatables are removed and/or allowed to settle.
Publicly Owner Treatment Works (POTW): POTW means a facility owned by the State, a political subdivision, municipal corporation or other public entity and which is used for treatment of pollutants.31
Public Comment Period: The open period during which the public is offered the opportunity to comment on a permit or other document such as a fact sheet, draft permit, tentative determination, regulation or other actions by the Department.
Public Hearing: A part of the administrative process during which the public can participate and comment on an action taken or to be taken by the Department.
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Raw Sewage: Wastewater that has not been subjected to any pollutant removal.
Receiving Waters: A surface water into which wastewater is discharged.32
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7Q10: The lowest stream flow for seven consecutive days expected to occur over a ten year period. Defined under COMAR as the "design stream flow."33
Sampling Frequency: The period of time, established by the permit, determining how often successive water samples must be taken.
Sanitary Sewer: Collection systems that convey domestic and industrial waste to the treatment plant. Sanitary Sewer Systems (SSSs) do not convey stormwater.
Sanitary Sewer Overflow: An overflow from a sanitary sewer system caused by broken pipes, vandalism, blockages and other events.
Secondary Treatment: The second step in wastewater treatment that, through various methods, uses bacteria to consume the organic materials in wastewater.34
Self-monitoring: Sampling or monitoring performed by the wastewater facility for compliance purposes as required under the Clean Water Act.
Sewage: The wastewater discharged from residents, businesses and industries into sewers.35
Sewer or sewerage system: The pipes or conduits that carry wastewater from the source to the treatment work.36 Sewerage is the entire collection system for sewage, including sewers, collection lines, pumping stations and treatment works.
Sludge: Under COMAR, sludge is defined as the settleable solids that are (1) naturally present in waters and wastewaters; or (2) derived from nonsettleable matter by chemical coagulation and precipitation or by biological flocculation and precipitation.37
Storm sewer: A system of underground pipes or conduits that collect and carry storm water runoff.
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Tentative Determination: The decision of the Department whether or not to issue a proposed permit based upon the application received. The Department must prepare a fact sheet or statement of basis for its decision and offer an opportunity for public comment.38
Tertiary Treatment: The third level of wastewater treatment that removes pollutants such as nutrients, BOD and suspended solids.
Thermal Pollution: Discharge of heated water beyond the permissible limit in the permit or in a manner that can kill or injure aquatic organisms.
Total kjeldahl nitrogen (TKN): The total amount of organic nitrogen.
Total Suspended Solids (TSS): A measure of the filterable solids present in a sample, as determined by the method specified in 40 CFR Part 136.39
Toxic Pollutant: Under the Clean Water Act, the term “toxic pollutant” means those pollutants, or combination of pollutants, including disease-causing agents, which after discharge and upon exposure, ingestion, inhalation or assimilation into any organism, either directly from the environment or indirectly by ingestion through food chains, will, on the basis of information available to the Administrator, cause death, disease, behavioral abnormalities, cancer, genetic mutations, physiological malfunctions (including malfunctions in reproduction) or physical deformities, in such organisms or their offspring.40
Turbidity: The measurement of suspended organic and inorganic matter in water (cloudiness) as determined by the ability of light to penetrate.
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Upset: An exceptional incident in which there is unintentional and temporary noncompliance with the permit because of factors beyond the reasonable control of the permittee. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation.41 (Not the same as a Bypass).
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Waste load Allocation (WLA): WLA means the identification and allotment by the Department of quantities of residual wastes which may be discharged from point sources. The allotment shall include limits on the quantities of wastes which may be discharged; consideration of seasonal variations; a margin of safety; and the contribution of non-point sources.42
Water Quality Based Permit: A permit with limits more stringent than would be applicable under a technology-based permit.
Water Quality Standard (WQS): A law or regulation that consists of the beneficial uses of a waterbody, the numeric and narrative criteria that are necessary to protect the use or uses of that particular waterbody, and an antidegradation statement.43 [See criteria (narrative) and criteria (numeric)].
Water Quality Criteria: Water quality criteria are comprised of numeric and narrative criteria. Numeric criteria are scientifically derived ambient concentrations developed by EPA or States for various pollutants of concern to protect human health and aquatic life. Narrative criteria are statements that describe the desired water quality goal.44
Wastewater Treatment Plant (WWTP): A facility specifically designed to treat wastewater and remove pollutants from the waste stream before discharging it into the environment.
Whole Effluent Toxicity (WET) Test: A test to determine the toxicity of the total effluent on aquatic organisms.
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