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MEMORANDUM

TO: Public Record for the NPDES Electronic Reporting Rule

EPA Docket Number EPA-HQ-OECA-2009-0274 (www.regulations.gov)

FROM: Carey A. Johnston, P.E.

USEPA/OECA/OC

ph: (202) 566 1014

johnston.carey@epa.gov

DATE: 14 May 2014

SUBJECT: Data Elements Supporting the Clean Watersheds Needs Survey [DCN 0113]

Overview 

EPA is seeking comment on including into Appendix A of the NPDES Electronic Reporting 

Rule two data elements that support the Clean Watersheds Needs Survey. EPA conducts this 

survey under authority of Sections 205(a) and 516 of the Clean Water Act. These changes would 

reduce burden on states by eliminating most of the need for EPA to collect these two data 

elements from states as part of its quadrennial survey. 

These two POTW data elements are: (1) POTW Wastewater Treatment Technology Level 

Description [The highest level of treatment (e.g., primary equivalent to secondary, secondary, 

advanced, other) that the POTW provides at each outfall]; and (2) POTW Wastewater 

Treatment Technology Unit Operations [The treatment technology unit process information at 

each outfall for POTWs greater than 10 MGD]. Example lists of wastewater treatment 

technology level descriptions and unit operations are provided below.
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Proposed data Elements Supporting EPA’s Clean Watershed Needs Survey:

Sections 205(a) and 516 of the Clean Water Act

POTW Wastewater 

Treatment Technology 

Level Description

This data element describes the level of wastewater treatment technology (e.g., 

primary equivalent to secondary, secondary, advanced, other) at each outfall. This 

data element only applies to POTWs.

122.21 (j) (3) (iii) and 

CWA 516 1,2

POTW Wastewater 

Treatment Technology 

Unit Operations

The code/description of the wastewater treatment technology unit operations (e.g, 

grit removal, flow equalization, complete mix activated sludge secondary treatment, 

biological nitrification) at each outfall. This data element only applies to POTWs that 

discharge above 10 MGD.

122.21 (j) (2) (ii) (A) and 

CWA 516 1,2

Options for POTW Wastewater Treatment Technology Level Description (Select One of The Following)

• Raw Discharge: Effluent that is treated.

• Primary Treatment (45mg/L<BOD): Process in which the effluent that is treated to remove floating debris and solids 

by screening and sedimentation.

• Advanced Primary: Process in which chemicals are added to further treat primary effluent and increase the amount of 

solid matter removed.

• Secondary Wastewater Treatment: The minimum level of treatment required for discharges from all municipal 

wastewater treatment facilities by the Clean Water Act; facilities granted ocean discharge waivers under section 

301(h) are exempted from this requirement. The effluent must meet the EPA’s minimum removal standards for 

Biochemical Oxygen Demand (less than or equal to 30 mg/L), total suspended solids (TSS), and pH.

• Advanced Treatment: A level of treatment that is more stringent than secondary treatment or produces a significant 

reduction in nonconventional or toxic pollutants present in the facility’s effluent. The treatment is generally 

considered advanced if the BOD is less than or equal to 20 mg/L or one or more advanced treatment indicators are 

present. Advanced Treatment indicators include: BOD (Biochemical Oxygen Demand), Nitrogen Removal, 

Phosphorous Removal, Ammonia Removal, Metal Removal, and Synthetic Organic Removal. 

All of the above categories (except Raw Discharge) will include their own drop down selections and each will also include a 

drop down for Disinfection and Solids Handling.
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Options for POTW Wastewater Treatment Technology Unit Operations

The following are potential wastewater treatment technology unit operation selections 

for this data element. It is applicable for each outfall at a facility. This data element only applies 

to POTWs that discharge above 10 MGD.

Preliminary Treatment

Aerated Grit Chambers

Comminution

Equalization, at POTW

Flotation

Grit Removal

Dewatering assc. w/Grit Removal

Microstrainer, Primary

Pumping, Influent

Pump Stations

Screen (Bar Rack & Coarse)

Screen (Fine & Microstrainers)

Screen, Mechanical Bar

Screen, Bar

Scum Removal

Storage (In-line)

Storage (Off-line, e.g. Retention Basins) 

Storage (Lagoon)

Storage (Underground)

Storage (Off-line)

Storage (Other)

Subsurface Flow

Swirl Concentrators

Vortex Solids Separators

Primary Treatment

Aerated Grit Chambers

Aeration (Pre-treatment)

Aeration (Post-treatment)

Chemical Addition - Coagulants

Chemical Addition (Alum), Primary

Chemical Addition (Ferric Chloride), Primary

Chemical Addition (Ferrous Sulfate), Primary

Chemical Addition (Other), Primary

Clarification, In-Channel
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Clarification, Intermediate

Clarification, Tube Settlers

Clarification, Other

Equalization, Flow

Imhoff Tank

Lagoon, Aerated

Lagoon, Anaerobic

Lagoon, Gas Utilization

Land Application, Slow Rate, W/O Underdrain

Land Application, Slow Rate, With Underdrain

Land Application, Other

Microstrainer, Secondary

Neutralization

Overland Flow System

Pond, Total Containment

Rapid Infiltration System, W/O Underdrain

Rapid Infiltration System, With Underdrain

Rapid Infiltration System, Other

Sedimentation, Primary

Septage Treatment – Separate Stage

Trickling Filter Plastic Media

Trickling Filter, Redwood Slats

Trickling Filter, Rock Media

Trickling Filter, Biofilter

Trickling Filter, Other Media

Secondary Treatment

Activated Sludge, Anaerobic/Anoxic/Oxic

Activated Sludge, Complete Mix

Activated Sludge, Conventional

Activated Sludge, Extended Aeration

Activated Sludge, High Rate

Activated Sludge, Pure Oxygen

Activated Sludge, Step Aeration

Activated Sludge, With Biological Denitrification

Activated Sludge, with Phosphorus Removal

Activated Sludge, Other Mode

Chemical Addition (Alum), Secondary

Chemical Addition (Ferric Chloride), Secondary

Chemical Addition (Other), Secondary

Chemical addition (Phosphorus), Secondary
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Clarification, Secondary

Duckweed (Lemna)

Filter, Slow Sand

Filter, Denitrification with Coarse Media

Filter, Denitrification with Fine Media

Filter, Mixed Media

Filter, Moving Bed

Filter, Pressure

Filter, Rapid Sand

Filter, Rock

Filter, Other

Flocculation

Freesurface/Wetland (Marsh System)

Growth Process, Other Attached

Growth Process, Other Suspended

Lagoon, Aerated

Lagoon, Anaerobic

Lagoon, Facultative

Lagoon, Natural (Large Area)

Lagoon, Other

Package Plant, Rotating Biological Contractor (RBC)

Package Plant (Other)

Pond, Stabilization

Reactor (Oxidation Ditch)

Reactor, Sequencing Batch (SBR)

Reactor (Fixed Film)

Reactor (Other)

Sedimentation, Chemical Precipitation

Sedimentation, Other

Settling Tank

Trickling Filter, Plastic Media

Trickling Filter, Redwood Slats

Trickling Filter, Rock Media

Trickling Filter, Biofilter

Trickling Filter, Other Media

Aeration

Pumping, Effluent

Plant Closure Costs

Advanced Treatment

Activated Carbon, Granular
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Activated Carbon, Powdered

Activated Carbon, Other

Activated Sludge, Anaerobic/Anoxic

Activated Sludge, Contact Stabilization

Activated Sludge, Extended Aeration

Activated Sludge, With Biological Denitrification

Activated Sludge, Oxic

Activated Sludge, Other

Ammonia Stripping

Biological Denitrification

Carbon Regeneration

Chemical Addition (Alum), Tertiary

Chemical Addition (Ferric Chloride), Tertiary

Chemical Addition (Polymer)

Chemical Addition (Sodium Hydroxide)

Chemical Addition (Sodium Hypochlorite)

Chemical Addition (Other)

Distillation

Duckweed (Spirodela)

Duckweed (Wolffia)

Duckweed (Other)

Evaporation

Filter (Activated Bio-)

Filter (Gravity Sand Beds, single media)

Filter (Other)

Foam Fractionation

Freezing

Gas-Phase Separation

Ion Exchange

Lagoon, Polishing

Lime Treatment, Single Stage Primary

Lime Treatment, Two Stage Primary

Lime Treatment, Two Stage Tertiary

Lime Treatment, Other

Membrane Process (Dialysis)

Membrane Process (Electrodialysis)

Membrane Process (Reverse Osmosis)

Membrane Process (Other)

Nitrification, Biological (Combined and BOD Reduction)

Nitrification, Biological (Separate Stage)

Nitrification, Biological (Other)
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Phosphorus Removal, Biological

Phosphorus Removal, Biological (Modified Bardenpho)

Phosphorus Removal, Biological (Phostrip)

Phosphorus Removal, Biological (Other)

Phosphorus Removal, Chemical 

Reactor (Oxidation Ditch)

Reactor, Vertical Loop

Reactor, Other

Recarbonation

Reduction

Sedimentation, Other

Solvent Extraction

Sorption

Enhanced Nutrient Removal (ENR)

Biological Nutrient Removal (BNR) Membrane Bio-Reactor (MBR)

Biological Nutrient Removal (BNR) - Aeration

Biological Nutrient removal (BNR) - Other

Advanced Treatment (Other)

Plant Closure Costs

Disinfection

Dechlorination, Bisulphite

Dechlorination, Sulphur Dioxide 

Dechlorination, Other

Disinfection, Breakpoint Chlorination

Disinfection, Chlorination

Disinfection, Gaseous Chloride

Disinfection, Liquid Chloride

Disinfection, Other Chemical

Disinfection, Ozonation

Disinfection, Ultraviolet Radiation

Disinfection, wet Weather

Disinfection, Sodium Hypochlorite

Disinfection, Chlorine Dioxide

Disinfection Hypochlorite Bisulfite

Disinfection, Other

Solids Handling

Biosolids Aerated Storage

Biosolids Aerobic Digestion, Air

Biosolids Aerobic Digestion, Autothermal Thermophilic
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Biosolids Aerobic Digestion, Oxygen

Biosolids Air Drying, Sand Beds

Biosolids Air Drying, Other Media

Biosolids Anaerobic Digestion, Thermophilic

Biosolids Anaerobic Digestion, Other

Biosolids Digestion, Other

Biosolids Chemical Addition (Alum)

Biosolids Chemical Addition (Ferric Chloride)

Biosolids Chemical Addition (Polymer)

Biosolids Chemical Addition (Other)

Biosolids Chlorinate Oxidation (Purifax)

Biosolids Co-Incineration With Solid Waste

Biosolids Co-Pyrolysis With Solid Waste

Biosolids Composting, In-Vessel

Biosolids Composting, Static Pile

Biosolids Composting, Window

Biosolids Composting, Other

Biosolids Digestor Gas Utilization Facilities

Renewable Energy Photovoltaic Systems

Biosolids Digestor Gas Flaring

Biosolids Disposal (Monofil)

Biosolids Disposal (Ocean)

Biosolids Disposal (Waste Receiving Station)

Biosolids Disposal (Other)

Biosolids Distribution And/Or Marketing of Biosolids

Biosolids Elutriation

Biosolids Freezing

Biosolids Heat Drying

Biosolids Heat Recovery and Utilization

Biosolids Incineration, Fluidized Bed

Biosolids Incineration, Multiple Hearth

Biosolids Incineration, Rotary Kiln

Biosolids Incineration (Other)

Biosolids Lagoon

Biosolids Land Treatment (Spreading)

Biosolids Landfill/Trenching

Biosolids Lime Stabilization

Biosolids Mechanical Dewatering (Centrifuge)

Biosolids Mechanical Dewatering (Filter Press)

Biosolids Mechanical Dewatering (Pressure Filter)

Biosolids Mechanical Dewatering (Vacuum Filter)
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Biosolids Mechanical Dewatering (Other)

Biosolids Pyrolysis

Biosolids Recalcination

Biosolids Thickening, Dissolved Air Flotation

Biosolids Thickening, Gravity

Biosolids Thickening, tank

Biosolids Thickening, Other

Biosolids Vibration

Biosolids Wet Air Oxidation

Biosolids (Heat Treatment-Blowers)

Biosolids Other Treatment

Chemical Addition (Polymer)

Biosolids Cake Storage Hopper

Biosolids Land Costs (Storage)

Biosolids Land Costs (Landfill)