Current through Register No. 13, March 27, 2025
(a) Wetlands
shall be delineated in accordance with RSA 482-A and Env-Wt 100 et
seq.
(b) For sites in an
undisturbed natural state, the presence or absence of hydric soils shall be
determined by evaluating shovel or auger holes to a depth of 2 feet. A
sufficient number of holes shall be dug to establish the hydric soil boundary
to within 5 feet.
(c) The
suitability of a site as a receiving layer shall be determined in accordance
with (d), below, if any of the following apply:
(1) No fill has been placed on the site, but
the natural vegetation and soil have been disturbed to the extent that it is
not possible to determine the presence or absence of hydric soils based on a
visual examination of the soil horizons revealed by shovel or auger holes;
or
(2) Fill has been placed on the
site prior to 1967 for tidal areas, or prior to 1969 for freshwater areas, or
pursuant to authorization of the New Hampshire water resources board prior to
1979, or pursuant to a valid permit from the New Hampshire wetlands board
issued prior to August 9, 1996, or issued by the department pursuant to RSA
482-A, and either:
a. Visual examination of a
test pit establishes that the original soil was hydric, or
b. It cannot be determined by a visual
examination of a test pit whether the original soil was a hydric soil or not.
(d) If any
of the conditions set forth in (c) above apply, the presence of a suitable
receiving layer shall be determined based on the hydrology of the site as shown
by data obtained from piezometric monitoring wells in accordance with the
following:
(1) One monitoring well shall be
placed in the proposed leaching area and one monitoring well shall be placed at
a point between 65 and 75 feet downgradient of the proposed leaching
area;
(2) Additional monitoring
wells shall be installed as needed to establish the 20,000 square foot area
required for subdivision applications;
(3) Water level readings shall be taken every
2 weeks;
(4) Water level readings
may be taken more often at the option of the property owner;
(5) All readings taken shall be submitted
quarterly, in writing, to the department;
(6) Water levels shall be monitored for a
period of 2 years;
(7) Based on the
recorded data, the applicant shall estimate the seasonal high water table,
taking into account weather conditions such as the amount of precipitation over
the period, major storm events, frosts and thaws;
(8) The applicant shall submit the estimate
together with supporting data to the department; and
(9) The receiving layer shall be deemed
suitable if the estimated seasonal high water table is no closer than 15 inches
to the existing ground surface.
