Tenn. Comp. R. & Regs. 1200, 1200-01, ch. 1200-01-06, app II

Current through December 10, 2024

Appendix II

SOIL ABSORPTION / PERCOLATION RATES AND CORRESPONDING ABSORPTION AREA REQUIREMENTS

Absorption / Percolation	Absorption Area (As Trench Bottom Rates Area)
(mpi)	(ft²/gallon)	(ft²/bedroom)
10	1.2	165
15	1.4	190
30	2.0	250
45	2.5	300
60	2.9	330
75	3.2	370
80	3.3	380
85	3.4	390
90	3.5	400
95	3.6	415
100	3.7	430
105	3.8	445

NOTE: Round percolation rates to next highest increment of five (5).

NOTE: Trenches of two (2) to three (3) feet in width are preferred. For trenches greater than three(3) feet in width, increase the absorption area by the following factors:

Trench Width	Factor
4 ft	1.33
6 ft	1.50
8 ft	1.60

EXAMPLES:

1. The soil absorption rate is 15 minutes per inch. A factory with a daily flow of 3,000 gallons is to be located on this site.

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2. The soil absorption rate is 30 minutes per inch. A 4 bedroom house is to be constructed.

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NOTE: Flow rates for non-residential establishments shall be based on the memo from Kent D.

Taylor to the Division of Ground Water Protection Field Office Managers dated July 8, 1993, regarding expected sewage flow from non-residential establishments.

Tenn. Comp. R. & Regs. 1200, 1200-01, ch. 1200-01-06, app II