New Jersey Administrative Code › Title 7 - ENVIRONMENTAL PROTECTION › Chapter 9A - STANDARDS FOR INDIVIDUAL SUBSURFACE SEWAGE DISPOSAL SYSTEMS › Subchapter 9 - EFFLUENT DISTRIBUTION NETWORKS › Section 7:9A-9.2 - Dosing tanks

Current through Register Vol. 56, No. 14, July 15, 2024
(a) A dosing tank
				using a siphon or pump is required for systems using gravity or pressure dosing
				and shall meet the requirements of (b) through (f) below.
(b) The minimum capacity of dosing tanks
				using pumps shall be determined as follows:
1. Dosing tanks using pumps shall have
				sufficient capacity to distribute septic tank effluent equally to all parts of
				the disposal field during each dosing cycle and to provide adequate reserve
				storage capacity in the event of a pump malfunction. The total liquid capacity
				shall be great enough to accommodate the minimum required dose volume (V[d])
				determined as prescribed in (b)2 below, plus the minimum required reserve
				storage capacity determined as prescribed in (b)3 below. Additional volume must
				be provided above the pumping level to accommodate the volume of water
				displaced by the pump and controls (V[pd]) as well as any quantity of effluent
				which will drain back into the dosing tank when the pump shuts off at the end
				of a dosing cycle (V[cp]). Additional volume must be provided below the pumping
				level so that the pump may be placed on a pedestal, above the dosing tank
				bottom, to prevent the pump from drawing in air or whatever solids may
				accumulate in the bottom of the dosing tank.
2. The dose volume (V[d]) shall be determined
				based upon the soil permeability or percolation rate, daily volume of sewage
				(Q) and the total internal volume of the distribution network (V), as shown
				below. In the case of pressure dosing systems, the volume of the distribution
				network, V, shall include the volume of the delivery pipe (V[p]), the manifold
				(V[m]) and the laterals (V[l]).
Soil
Percolation
Required
Required
Permeability
Rate
Dose
						  Volume
Dose Volume
(in/hr)
(min/in)
Gravity
						  Dosing
Pressure Dosing
6-20
3-15
minimum of 75
						  percent
minimum of 10V<2>
V<1>
maximum of 25 percent Q
maximum of 25
						  percent
Q
0.2-6
15-60
minimum of 75 percent
						  V
minimum of 10V
maximum of 100 percent Q
maximum of 100
						  percent
Q
[LESS THAN]1[GREATER THAN] In cases where 75 percent V is
				  larger than 25 percent Q, the 25 percent Q maximum rather than the percent
				  minimum shall be observed.
[LESS THAN]2[GREATER THAN] In cases where 10V is larger than
				  25 percent Q, the 25 percent Q maximum rather than the 10V minimum shall be
				  observed.
3. Reserve
				capacity is the inside volume of the dosing tank which lies between the level
				at which the high-water alarm switch is set and the invert elevation of the
				tank inlet, as shown in Figure 13 of Appendix A. A minimum reserve capacity
				equal to the daily volume of sewage shall be required except where a stand-by
				pump is provided which is equivalent in performance capacity to the primary
				pump and which will switch on automatically in the event that the primary pump
				malfunctions.