N.H. Admin. Code § Env-Ws 901.19
Current through Register No. 50, December 12, 2024
Classification points for wastewater treatment plants shall be assigned in accordance with Table 901.2 and Table 901.3:
Table 901.2 Point System for the Classification of Wastewater Treatment Plants
| Item | Points |
| Size | |
| Maximum population equivalent (p.e.) served, peak day | 1 per 10,000 p.e. or part thereof |
| Design flow (avg. day) or peak month's flow (avg. day) in million gallons per day (mgd), whichever is larger | 1 per MGD or part thereof |
| Effluent Discharge | |
| Receiving stream (sensitivity) See Table 901.3 for Range | 1-6 |
| Land disposal - evaporation | 2 |
| Subsurface disposal | 5 |
| Rapid infiltration basins | 6 |
| Variation in Raw Wastes (slight to extreme) See Table 901.3 for Range | 0-6 |
| Pretreatment | |
| Screening, comminution | 3 |
| Grit removal | 3 |
| Plant pumping of main flow | 3 |
| Primary Treatment | |
| Primary clarifiers | 5 |
| Combined sedimentation/digestion | 5 |
| Chemical addition (except chlorination and enzymes) | 4 |
| 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 w/secondary clarifiers | 10 |
| Fixed film media unit without/secondary clarifiers | 15 |
| Subsurface disposal | 5 |
| Rapid infiltration basins | 6 |
| Overland flow | 6 |
| Advanced Waste Treatment | |
| Polishing pond | 2 |
| Chemical/physical - without secondary | 15 |
| Chemical/physical - following secondary | 10 |
| Biological or chemical/biological | 12 |
| Ion exchange | 10 |
| Reverse osmosis or electrodialysis | 15 |
| Chemical recovery, carbon regeneration | 4 |
| Spray irrigation | 8 |
| Overland flow | 6 |
| Filtration | 8 |
| Solids Handling | |
| 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 |
| Autothermal Thermophilic Aerobic Digestion (ATAD) | 8 |
| Disinfection | |
| Chlorination or comparable | 5 |
| On-site generation of disinfectant | 5 |
| Dechlorination | 5 |
| Ultraviolet | 5 |
| Laboratory Control by Plant Personnel | |
| See Table 901.3 for range Bacteriological (complexity) | 0-10 |
| Chemical/physical (complexity) | 0-10 |
Table 901.3: Point System for the Evaluation of Effluent Discharge and
Laboratory Complexity
| Item | Points |
| Effluent Discharge | |
| Receiving stream sensitivity. The key concept 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 |
| Variation in raw wastes (slight to extreme) | |
| The key concept 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 |
| Laboratory Control by Plant Personnel | |
| Bacteriological/biological (complexity). The key concept is to credit lab work done by plant personnel. Point values are: | 0-10 |
| Lab work done outside the plant | 0 |
| Bacteriological analysis (membrane filter, MPN) | 5 |
| Biological identification | 7 |
| Virus studies or similarly complex work conducted on site | 10 |
| Chemical/physical (complexity). The key concept is to credit lab work done on-site by plant personnel. Point values are: | 0-10 |
| All lab work done outside the plant | 0 |
| Push button or visual methods for simple tests such as: pH, settleable solids - up to | 3 |
| Additional procedures such as: DO, COD, BOD, gas analysis, filtrations, solids, volatile content - up to | 5 |
| More advanced determinations, such as: nutrients, total oils, phenols, etc. - up to | 7 |
| Highly sophisticated instrumentation such as atomic absorption and gas chromatography | 10 |
N.H. Admin. Code § Env-Ws 901.19
#8327, eff 4-23-05