N.H. Admin. Code § Env-Wq 304.28

Current through Register No. 50, December 12, 2024
Section Env-Wq 304.28 - Classification Points for Wastewater Treatment Plants

Classification points for wastewater treatment plants shall be assigned in accordance with Table 304.3:

Table 304.3 Point System for the Classification of Wastewater Treatment Plants

ItemPoints
Size
For industrial plants only, maximum population equivalent (pop.eq.) served, peak day 1 per 10,000 pop.eq. or part thereof
For all other plants, the larger of design flow (avg. day) or peak month's flow (avg. day) in gallons per day (GPD) 0.1 per 100,000 GPD
Effluent Discharge
Receiving stream sensitivity. Primary consideration is the degree of dilution provided under low flow conditions. Point values are: 1-6
"Effluent limited segment" in EPA terminology; secondary treatment is adequate 1
More than secondary treatment is required 2
"Water quality limited segment" in EPA terminology; stream conditions are very critical (dry run, for example) and a very high degree of treatment is required 3
Effluent used in direct recycle and reuse system 6
Land disposal - evaporation 2
Subsurface disposal 5
Rapid infiltration basins 6
Variation in Raw Wastes (slight to extreme), including industrial discharge connections. Primary consideration is frequency or intensity of deviation or excessive variation from normal or typical fluctuations; such deviation can be in terms of strength, toxicity, shock loads, I/I, etc. Point values are: 0-6
Variations do not exceed those normally or typically expected 0
Recurring deviations or excessive variations of 100 to 200 percent in strength and/or flow 2
Recurring deviations or excessive variations of more than 200 percent in strength and/or flow 4
Raw wastes subject to toxic waste discharges 6
Pretreatment
Screening, comminution 3
Grit removal 3
Influent flow equalization 1
Plant pumping of main flow 3
Primary Treatment
Primary clarifiers 5
Combined sedimentation/digestion 5
Chemically enhanced primary treatment 7
Secondary Treatment
Activated sludge with secondary clarifiers (including extended aeration, sequencing batch reactors & oxidation ditches) 15
Stabilization ponds without aeration 5
Aerated lagoon 8
Sand filters 5
Fixed film media system 10
Subsurface disposal 5
Rapid infiltration basins 6
Overland flow 6
Advanced Treatment
Polishing pond 2
Chemical/physical, including ballasted treatment 12
Biological or chemical/biological 12
Ion exchange 10
erse osmosis or membrane filtration 15
Chemical recovery, carbon regeneration 4
Spray irrigation 8
Overland flow 6
Filtration 8
Solids Handling
Mechanical thickening 5
Anaerobic digestion 10
Aerobic digestion 6
Evaporative sludge drying 2
Mechanical dewatering 8
Solids reduction (incineration, wet oxidation) 12
Composting 7
Lime stabilization 5
Septage receiving 1
Disinfection
Chlorination or comparable 5
On-site generation of disinfectant 5
Dechlorination 5
Ultraviolet 5
Effluent post aeration 2
Effluent flow equalization 1
Odor Control. Primary consideration is complexity of odor control system operation and maintenance. Point values are: 0-2
Soil or carbon filters or equivalent 1
Chemical/wet scrubber systems or equivalent 2
SCADA System 1
Laboratory Control by Plant Personnel. Primary consideration is complexity of lab work done by plant personnel. Point values are: 0-10
Push button or visual methods for simple tests such as pH, chlorine residual, settleable solids 1
Standard procedures such as DO, COD, BOD, TSS, gas analysis, filtrations, solids, volatile content, nutrients, bacteriological analysis (membrane filter, MPN, E. coli, fecal coliform, Enterococci) 3
More advanced determinations, such as total oils, phenols, metals 5
Biological identification 7
Virus studies or similarly complex work conducted on site 10
Highly sophisticated instrumentation such as atomic absorption and gas chromatography 10

N.H. Admin. Code § Env-Wq 304.28

(See Revision Note at part heading for Env-Wq 304) #10392, eff 8-1-13