Section Env-Wq 711.02 - Secondary Settling Tanks: Number and Types of Units(a) Multiple secondary settling tank units capable of independent operation shall be provided.(b) A minimum of 3 independent secondary settling tanks shall be provided when the average daily design flow is equal to or greater than 5.0 MGD.(c) Secondary settling tanks for activated sludge may be rectangular or circular, and shall be designed to separate and concentrate mixed liquor, remove settled sludge, and skim, collect, and remove scum and other floatables.(d) Secondary settling tank walls shall: (1) Extend at least 6 inches above the surrounding ground; and(2) Provide not less than 12 inches of freeboard.N.H. Admin. Code § Env-Wq 711.02
(See Revision Note at chapter heading for Env-Wq 700) #8590, eff 3-25-06
Amended byVolume XXXIV Number 46, Filed November 13, 2014, Proposed by #10693, Effective 10/15/2014, Expires10/15/2024.