Wastewater must be treated by an approved septic tank prior to being discharged into a disposal field, unless the applicant receives a primitive system permit, as described in Section 5 or a holding tank permit as described in Sections 9 and 10. The use of an aerobic treatment unit or any other device in lieu of, or in conjunction with, a septic tank not be permitted by the LPI without prior approval of the device by the Department.
TABLE 7A
SEPTIC TANK CAPACITY
FOR DWELLING UNITS
Number of bedrooms per Unit | Minimum septic tank liquid capacity per Unit |
1 Bedroom | 750 gallons |
2 Bedrooms | 750 gallons |
3 Bedrooms | 1,000 gallons |
4 Bedrooms | 1,000 gallons |
5 Bedrooms | 1,250 gallons or |
For each additional | 250 gallons per bedroom |
Equation 7B Q=[M][GL][ST][LF] Where: Q is the liquid capacity of external grease interceptor, gallons; M is the total number of meals served per day; GL is the gallons of wastewater per meal, typ. 2.0 gallons; ST is the storage capacity, typ. 2; and LF is a loading factor depending on type of facilities present: LF is 1.0 with dish washing; and; LF is 0.5 without dish washing. |
Minimum pitch: Connecting pipes must have a minimum grade as follows:
TABLE 7B
Sizing for "Bio-Diffuser", "Infiltrator", "EnviroChamber", and "Contactor" proprietary disposal devices
Device | Model | Height | Configuration | |
Cluster | Trench | |||
Bio-Diffuser | Standard | 11 inches | 36 square feet/unit | 44 square feet/unit [a] |
Bio Diffuser | High Capacity | 16 inches | 36 square feet/unit [b] | 50 square feet/unit [c,d] |
Bio-Diffuser | Bio 2 | 12 inches | 28.8 square feet/unit [b] | 28.8 square feet/unit [c,d] |
Bio-Diffuser | Bio 3 | 12 inches | 26.4 square feet/unit | 43.2 square feet/unit |
Bio-Diffuser | Bio 2 | 12 inches | 28.8 square feet/unit [b] | 28.8 square feet/unit [c,d] |
Bio-Diffuser | ARC 18 | 12 inches | 2.5 square feet/linear foot [b] | 4.0 square feet/linea r foot [c,d] |
Bio-Diffuser | ARC 24 | 12 inches | 3.7 square feet/linear foot | 6.0 square feet/linea r foot |
Bio-Diffuser | ARC 36 Standard | 12 inches | 5.8 square feet/linear foot | 7.0 square feet/linea r foot |
Bio-Diffuser | ARC 36 High Capacity (HC) | 16 inches | 5.8 square feet/linear foot | 8.0 square feet/linea r foot |
Infiltrator | EQ 24 | 11 inches | 33.3 square feet/unit [b] | 33.3 square feet/unit [c,d] |
Infiltrator | Quick4 EQ 24 | 11 inches | 16.0 square feet/unit | 16.0 square feet/unit [c,d] |
Infiltrator | Quick4 EQ 24 LP | 8 inches | 10.8 square feet/unit | 14 square feet/unit [c,d] |
Infiltrator | Quick4 EQ 36 | 12 inches | 14.8 square feet/unit | 20.8 square feet/unit |
Infiltrator | Standard | 12 inches | 36 square feet/unit | 44 square feet/unit [a] |
Infiltrator | Quick4 Standard | 12 inches | 23.2 square feet/unit | 28 square feet/unit [a] |
Infiltrator | High Capacity | 16 inches | 36 square feet/unit | 50 square feet/unit [a] |
Infiltrator | Quick4 High Capacity | 16 inches | 23.2 square feet/unit | 32 square feet/unit [a] |
Contactor | EZ-24 | 12 inches | 16.5 square feet/unit | 6.21 square feet/linea r foot |
Contactor 75 | Contactor "C" | 12 inches | 36 square feet/unit | 44 square feet/unit [e] |
Contactor 100 | 100 | 12 inches | 48 square feet/unit | 57 square feet/unit |
Contactor 125 | 125 | 18 inches | 36 square feet/unit | 50 square feet/unit [e] |
Contactor | Recharger 180 | 20 inches | 44 square feet/unit | 63 square feet/unit |
Contactor 375 | Tripdrain | 30 inches | 64 square feet/unit | 90 square feet/unit [e] |
Contactor | Recharger 330 | 30 inches | 65.25 square feet/unit | 98.25 square feet/unit |
Contactor | Recharger 400 | 32 inches | 29 square feet/unit | 57.6 square feet/linea r foot |
Contactor | Field Drain C1-C4 | 8 inches | 57.8 square feet/unit | N/A |
Infiltrator Quick 4 Plus [f] | Without End Cap, Trench | Without End Cap, Cluster | ||
Quick4 Plus High Capacity | 8.0 square feet/linear foot | 5.8 square feet/linear foot | ||
Quick 4 Plus Standard | 7.0 square feet/linear foot | 5.8 square feet/linear foot | ||
Quick 4 Plus Standard LP | 7.0 square feet/linear foot | 5.8 square feet/linear foot | ||
Quick 4 Plus Equalizer 36 LP | 5.2 square feet/linear foot | 3.7 square feet/linear foot | ||
Quick 4 Equalizer 24 LP | 3.5 square feet/linear foot | 2.7 square feet/linear foot |
TABLE 7C
Sizing for "GeoFlow" "Enviro-Septic" and
"Infiltrator ATL" gravel-less disposal tubing
Device | Model | Configuration+ | |
Cluster | Trench | ||
GeoFlow | 10 inches | N/A | 5.0 square feet per linear foot |
Enviro-Septic & Advanced Enviro-Septic | 12 inches | N/A | 5.0 square feet per linear foot |
Infiltrator ATL System | 12 inches | N/A | 5.0 square feet per linear foot |
TABLE 7D
Sizing for "Geotextile Sand Filter"
gravel-less cloth disposal system
Device | Model | Configuration | |
Cluster[b] | Trench[a] | ||
GSF | Type A | 24 square feet/ unit | 24 square feet/unit |
GSF | Type B | 48 square feet/unit | 48 square feet/unit |
TABLE 7E
Sizing for Synthetic Aggregate Cylinders
EZflow Model | Height | Configuration | |
Cluster | Trench | ||
803H/ 803H GEO | 8 inches | 3.25 square feet per linear foot | 4.0 square feet per linear foot |
904H/ 904H GEO | 9 inches | 4.9 square feet per linear foot | 6.0 square feet per linear foot |
1201P/1201P GEO | 12 inches | N/A | 4.0 square feet per linear foot |
1202H/1202H GEO | 12 inches | 5.36 square feet per linear foot | 6.0 square feet per linear foot |
1203H/1203H GEO | 12 inches | 6.4 square feet per linear foot | 7.0 square feet per linear foot |
Table 7F
Minimum Porous Hose Effluent Quality
Total Suspended Solids | 10 milligrams per liter, 30-day arithmetic mean |
Five Day Biochemical Oxygen Demand | 10 milligrams per liter, 30-day arithmetic mean |
Total nitrogen | 53 milligrams per liter, five-month arithmetic mean |
Total coliform | 10 (Log 10) colony forming units per 100 milliliters |
Table 7G Minimum Drip Emitter Effluent Quality
Total Suspended Solids | 30 milligrams per liter, 30-day arithmetic mean |
Five Day Biochemical Oxygen Demand | 30 milligrams per liter, 30-day arithmetic mean |
Total nitrogen | 53 milligrams per liter, five-month arithmetic mean |
Total coliform | 100 (Log10) colony forming units per 100 milliliters |
TABLE 7H
PLUMBING MATERIAL STANDARDS FOR DISPOSAL SYSTEMS
ASTM NUMBER FOR PLASTIC PIPE MUST BE LATEST EDITION AS LISTED IN ANNUAL BOOK OF ASTM STANDARDS, PART 34 NOTES: (A) PLASTIC PIPE MUST BE SLEEVED WHEN PASSING THROUGH MASONRY (B) PERFORATED PIPE MUST BE USED WITHIN THE ACTUAL DISPOSAL FIELD (C) WATER AND SEWER PIPE LESS THAN 10 FEET (CENTER TO CENTER) OR WATER AND SEWER PIPE IN THE SAME TRENCH REQUIRES THE WATER PIPE TO BE ON A SHELF AT LEAST 18 INCHES ABOVE AND 24 INCHES (CENTER TO CENTER) APART FROM EACH OTHER (HORIZONTAL MEASURE) X = PERMISSIBLE |
x | x | x | x | x | ABS (ASTM D1527) Sch. 40, 80 |
x | x | ABS (ASTM D2282) SDR 13.5, 17, 21, 26 | |||
x | x | x | x | ABS (ASTM D2661) DWV Sch. 40 | |
x | x | x | ABS (ASTM D2751, F810) Sewer Grade | ||
x | x | Cast Iron | |||
x | Concrete (ASTM C75, C200) | ||||
x | x | x | PB (ASTM D2662) Pipe SDR 7, 9, 11.5, 15 | ||
x | x | x | PE (ASTM D1248) Straight Wall | ||
x | x | x | PE (ASTM D2239) Pipe SDR 5.3, 7,9, 11.5, 15, 19 | ||
x | x | x | PE (ASTM D2737) Tubing SDR 7.3, 9, 11 | ||
x | x | PE (ASTM 3350) Smooth Wall Pipe, SDR 38, 35 | |||
x | x | x | x | x | PVC (ASTM D1785) Sch. 40, 80, 120 |
x | x | x | PVC (ASTM D2241) SDR 13.5, 17, 21, 26, 32.5, 41,64 | ||
x | x | x | x | PVC (ASTM D2665) DWV Sch. 40 | |
x | PVC (ASTM D2629; F810) Thin Walled Perforated, Disposal Field Only | ||||
x | x | x | x | PVC (ASTM D3034) SDR 23.5, 26, 35, 41 |
PRESSURE SEWER (OR PRESSURE LINE FROM PUMP CHAMBER TO DISPOSAL AREA) EFFLUENT PIPE (LINE FROM TREATMENT TANK TO DISPOSAL FIELD FOOTPRINT) DISTRIBUTION PIPE (PIPING WITHIN THE DISPOSAL FIELD FOOTPRINT) (SEE B) BUILDING SEWER (WATER SERVICE IN SAME TRENCH) (SEE C) BUILDING SEWER (SEPARATE FROM WATER SERVICE) BUILDING SEWER (SEPARATE FROM WATER SERVICE) |
Table 7I
FRICTION LOSS IN SCHEDULE 40 PLASTIC PIPE FEET
OF HEAD LOSS PER 100 FEET OF PIPE
Flow | Pipe diameter in inches | ||
11/2 Inch | 2 Inch | 3 Inch | |
3 gpm | 0.07 feet | ||
4 gpm | 0.12 feet | ||
5 gpm | 0.18 feet | ||
6 gpm | 0.25 feet | 0.07 feet | |
7 gpm | 0.36 feet | 0.10 feet | |
8 gpm | 0.46 feet | 0.14 feet | |
9 gpm | 0.58 feet | 0.17 feet | |
10 gpm | 0.70 ft | 0.21 feet | |
11 gpm | 0.84 feet | 0.25 feet | |
12 gpm | 1.01 feet | 0.30 feet | |
13 gpm | 1.17 feet | 0.35 feet | |
14 gpm | 1.33 feet | 0.39 feet | |
15 gpm | 1.45 feet | 0.44 feet | 0.07 feet |
16 gpm | 1.65 feet | 0.50 feet | 0.08 feet |
17 gpm | 1.86 feet | 0.56 feet | 0.09 feet |
18 gpm | 2.07 feet | 0.62 feet | 0.10 feet |
19 gpm | 2.28 feet | 0.68 feet | 0.11 feet |
20 gpm | 2.46 feet | 0.74 feet | 0.12 feet |
25 gpm | 3.75 feet | 1.10 feet | 0.16 feet |
30 gpm | 5.22 feet | 1.54 feet | 0.23 feet |
35 gpm | 2.05 feet | 0.30 feet | |
40 gpm | 2.62 fee | 0.39 feet | |
45 gpm | 3.27 feet | 0.48 feet | |
50 gpm | 3.98 feet | 0.58 feet |
TABLE 7J
HOLDING CAPACITY OF PIPES
Diameter | Pipe Volume | |
Inches | Gallons/Foot | Length/Gallon |
1 1/4 | 0.0776 | 12 feet 10 5/8 inches |
1 1/2 | 0.1057 | 9 feet 5 1/2 inches |
2 | 0.1632 | 6 feet 1 1/2 inches |
2 1/2 | 0.2549 | 3 feet 11 3/4 inches |
3 | 0.3672 | 2 feet 8 3/4 inches |
4 | 0.6528 | 1 foot 6 inches |
5 | 1.0199 | 1 foot 0 inches |
6 | 1.469 | 8 inches |
7 | 1.999 | 6 inches |
8 | 2.611 | 4 1/2 inches |
1 gallon of water = 8.35 pounds
1 cubic foot of water = 7.48 gallons
10-144 C.M.R. ch. 241, § 7