"Seasonal high water table (SHWT)" means the level at which the uppermost soil horizon contains 2% or more distinct or prominent redoximorphic features that increase in percentage with increasing depth.
N.H. Admin. Code § Env-Wq 1502.56
(See Revision Note #1 at chapter heading for Env-Wq 1500) #9343, eff 1-1-09