N.H. Code Admin. R. Env-Wq 304.28
Current through Register No. 25, June 20, 2024
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
| Item | Points |
| 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. Code Admin. R. Env-Wq 304.28
(See Revision Note at part heading for Env-Wq 304) #10392, eff 8-1-13