20011551 Ver 5_Monitoring Report_20140821

The
Catena
Group 10 -B Millstone Drive
p Hillsborough, NC 27278
(919) 732 -1300
August 18, 2014
NC DWR, Wetlands Branch
1650 Mail Service Center
Raleigh, NC, 27699 -1650
Subject: Post Construction Monitoring Report #4, NCGC, Mount Airy, Surry
County, North Carolina
References: Permit No: SAW- 2011 -01765
The Catena Group, Inc. (Catena) has been retained by the North Carolina Granite
Corporation (NCGC) to conduct post construction monitoring of the structures installed
under the above referenced permit. Please find enclosed the Post Construction
Monitoring Report #4 as required in Special Condition E of the 404 permit and
Conditions 3 and 4 of the 401 Permit. Flow in the side channel and structure stability
both meet permit requirements. This is the final monitoring required under the terms of
both permits.
If we can provide any additional information or if you have any questions, please contact
me at 919- 732 -1300 (office) or 919- 417 -8027 (mobile).
Sincerely,
The Catena Group, Inc.
�G.
Michael G. Wood, NCLSS
President
Enclosures: Post Construction Monitoring Report #4
CC: Carlos Goad
North Carolina Granite Corporation
P.O. Box 151
Mount Airy, NC 27030
AUG 2 12014
IT -_ vna ouALITY
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Post Construction Monitoring Report #4
North Carolina Granite Corporation
Hydrologic Flow and Function of Side Channel Monitoring
In- Channel Structure Stability Monitoring
Mt. Airy, North Carolina
Prepared for:
North Carolina Granite Corporation
P.O. BOX 151
Mount Airy, NC 27030
Tel: [phone]
August 2014
20011551 v'S
Prepared by:
The
Catena
gGroup.
The Catena Group
410B Millstone Drive
Hillsborough, NC 27278
Tel: [phone]

t
Table of Contents
1.0 Introduction ........................................................................................... ............................... 1
2.0 Methodology .......................................................................................... ..............................1
2.1. Hydrologic Flow and Function of Side Channel Monitoring ........... ............................... 1
2.2. In- Channel Structure Stability Monitoring ....................................... ..................... ........... 2
3.0 Results and Discussion ......................................................................... ............................... 2
Appendix A — Figures
Appendix B — Photos
Appendix C — Raw Data Sheets
NCGC Monitoring Report #4
Catena Job# 4159
August 2014
Page i

1.0 INTRODUCTION
The North Carolina Granite Corporation (NCGC) received a 404 Permit (SAW- 2011 - 01765) on
September 5, 2012, and a 401 Water Quality Certification (No. 3936) on July 30, 2012,
authorizing impact to 265 linear feet of the Ararat River through the placement of 1,680 cubic
yards of granite to stabilize river banks while also deflecting now toward the intake of the
holding pond. In addition, after - the -fact authorization was given for an additional 600 cubic
yards of permanent fill for river bank reconstruction. To maintain flow in a side channel, a 2 -inch
PVC pipe was installed providing water from the Ararat River to the side channel. Both permits
were modified in February 2013, to allow a closed inlet structure between the Ararat River and
the holding pond.
The 404 and 401 Permits both included Special Conditions that must be met for the permits to be
valid. Specifically, Special Condition E of the 404 Permit and Condition 3 of the 401
Certification require that the side channel receiving the flow from the 2 -inch PVC pipe be
monitored biannually, each February and August, for two years following construction of the
stream structures. Hydrologic flow /function will be monitored to determine if the side channel
still provides habitat for aquatic life propagation and maintains biological integrity — indicated by
a measured flow of greater than 26,500 gallons /day. In addition, Condition 4 of the 401
Certification requires biannual monitoring of the in- channel structures to insure stability.
2.0 METHODOLOGY
On August 8, 2014, Kate Montieth and Nancy Scott of The Catena Group ( Catena) monitored
the site by walking the length of the side channel. Photos of the structures were taken at
previously established photo stations to document current conditions (Appendix B).
Z L Hydrologic Flow and Function of Side Channel Monitoring
Flow, or stream discharge, in the side channel was measured at one location (Appendix A:
Figure 1) using a Global Water flow meter (Model FP111). Flow was calculated using the
following formulas and measurements taken in the field:
Flow (stream discharge) = Q
Q = velocity (ft /sec) * area (ft)
• Area = width of stream (ft) * depth of stream (ft)
At each location, stream width was divided into equal intervals and flow (velocity) was
measured at each interval; raw data sheets are in Appendix C. Using the above formulas, flow
was calculated for each location.
NCGC Monitoring Report #4 August 2014
Catena Job# 4159 Page 1

22 In- Channel Structure Stability Monitoring
The main channel of the Ararat River was walked from below the lower structure (double drop
cross vane) upstream to the bridge over Linville Road (SR 1727). Structures were visually
inspected from the bank and photos were taken at four photo points (Appendix A and B).
3.0 RESULTS AND DISCUSSION
Flow was measured only at the upper cross - section ( #2 in previous reports) of the side channel.
Flow at the upper cross - section ( 42) was measured at 154,245 gal /day (Table 1). As occurred
during the August 2013 and February 2014 monitoring periods, flow at the lower cross - section
(#1) was not able to be accurately measured due to the presence of aquatic vegetation hindering
the flow meter readings. Therefore, only the flow at the upper cross - section ( #2) is reported here
with the assumption that downstream flow would be at a minimum equal to the upstream.
Conditions of the permit require measured flow to be a minimum of 26,500 gal /day. Therefore,
as of this forth monitoring period, Special Conditions E and 3 have both been met and exceeded.
Table 1. Flow (gal/day in side channel to Ararat River
Monitoring Period
Survey Date
Cross - section #1
Cross - section #2
#1
March 28, 2013
71,957 gal/day
92,423 gal/day
#2
August 30, 2013
—
36,804 gal/day
#3
February 25, 2014
88,869 gal/day
#4
August 8, 2014
154,254 gal /day
Construction of the in- stream structures was completed on March 15, 2013. Inspection of the
structures during this monitoring period did not indicate any instability; therefore Condition 4 of
the 401 Certification has been met.
As all permit conditions have been successfully met and documented, this will be the final
monitoring report.
NCGC Monitoring Report #4 August 2014
Catena Job# 4159 Page 2

Appendix A:
Figures
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1 17
Cross-Section,
cti
C Cross_Secti #1
Cross - Section
DI
N
A
ON
PIC PIC
Oy
jr-A

Appendix B:
Photos
NCGC Monitoring Report #4 August 2014
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Hydrologic Flow and Function of Side Channel Monitoring
Photo Station 4: Side Channel enters Ararat at
center of photo (yellow arrow)
Photo Station 4: Upstream of side channel nexus
with Ararat River
Photo Station 4: Downstream of side channel Cross - Section 1: After flow measurement
nexus with Ararat River
Cross - Section 2: Before flow measurement
NCGC Monitoring Report #4 August 2014
Catena Job# 4159 Page 6

In- Channel Structure Stability Monitoring
Photo Station 1: Looking Downstream at
structures in Ararat from bridge over Linville
Road (SR 1727)
Photo Station 2: Single Wing Deflector
Photo Station 3: W -weir
NCGC Monitoring Report #4
Catena Job# 4159
Photo Station 1: Looking Upstream Ararat from
bridge over Linville Road (SR 1727)
Photo Station 2: NCGC intake structure with
flood gate
Photo Station 3: Upstream towards bridge.
August 2014
Page 7

Double Drop Cross Vane
NCGC Monitoring Report #4 August 2014
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Appendix C:
Raw Data Sheets
NCGC Monitoring Report #4 August 2014
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Appendix C:
Raw Data Sheets
NCGC Monitoring Report #4 August 2014
Catena Job# 4159 Page 9