HomeMy WebLinkAbout20140189 Ver 1_Some soil comments_20151013Strickland, Bev
From: Haupt, Mac
Sent: Tuesday, October 13, 2015 10:35 AM
To: Scarbraugh, Anthony
Cc: Hughes, Andrea W SAW
Subject: Some soil comments regarding Arrington Bridge III
Attachments: Figure 9 with soil areas of concern in mit plan.pdf
Anthony,
I have looked at the Arrington Bridge III Mitigation Plan and here are my comments:
1. There are three soils series mapped on site which are hydric:
a. Coxville- (Typic Paleaquult)
b. Pantego- (Umbric Paleaquult), probably the wettest...
c. Weston- (Typic Paleaquult)
2. Other soils series while not hydric may have hydric inclusions, however, a number of these soils are quite sandy
and therefore usually moderately to well drained,
3. The wetland hydrologic success criteria of 8% is acceptable given the series on site, but I certainly would not
have gone lower,
4. There are several areas in the wetland restoration shaded areas that have significant non -hydric polygons and
other areas which will susceptible to drainage given the surrounding land use and soils types. These areas of
concern are marked in the attachment.
5. These areas of concern were supported by several borings in the 2015 Hydric Soil Assessment in the document
(boring #s: 222, 228, 229, and 235)
6. 1 would recommend a gauge be placed in these noted polygons. In addition, they may want to put a couple of
gauges near the boundaries of the wetland restoration shaded areas which are located near borrow pits.
7. 1 could not reproduce some of the numbers in their modelling approach but I don't think we should belabor that
now...
8. 1 am in part concerned about excessive drainage in areas while at the same time concerned there may be a lot of
standing water in the first several years (I know those points conflict, just a comment...), for example, some of
the model numbers plus seeing a channel plug with a spillway...
I guess just cut and paste these as you see fit .... thanks
Mac
Mac Haupt - LSS
401 & Buffer Permitting Unit
Division of Water Resources, NCDEQ
Office 919-807-6476