20201195 Ver 17_More Info Recevied_20200723

Strickland, Bev
From: Thames, Kelly <[e-mail]>
Sent: Thursday, July 23, 2020 6:28 PM
To: Homewood, Sue
Subject: RE: [External] CLT Airport Public Notice Response
Attachments: AppendixE_Proposed Monitoring Plan_20200717.docx
Follow Up Flag: Follow up
Flag Status: Flagged
External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachmentm
[e-mail]
Sue,
Please find attached the revised monitoring plan in word format in case you'd like to add comments easier.
Don't hesitate to reach out to discuss further or if you have any clarifying questions you'd like me to answer.
Thanks!
Kelly
Kelly Thames, Pws
D 704.338.6710 M 704.996.9986
hdrinc.com/follow-us
From: Homewood, Sue [mailto:[e-mail]]
Sent: Monday, July 13, 2020 8:28 AM
To: Thames, Kelly <[e-mail]>
Cc: Geiger, Ronald A. <[e-mail]>
Subject: RE: [External] CLT Airport Public Notice Response
CAUTION: [EXTERNAL] This email originated from outside of the organization. Do not click links or open attachments
unless you recognize the sender and know the content is safe.
Thank you Kelly,
I will consider the application on hold until receipt of the updated monitoring plan.
Sue Homewood
Division of Water Resources, Winston Salem Regional Office
Department of Environmental Quality
336 776 9693 office
336 813 1863 mobile
Sue. [e-mail]
450 W. Hanes Mill Rd, Suite 300
Winston Salem NC 27105
1

From: Thames, Kelly <[e-mail]>
Sent: Monday, July 13, 2020 7:47 AM
To: Homewood, Sue <[e-mail]>
Cc: Geiger, Ronald A. <[e-mail]>
Subject: RE: [External] CLT Airport Public Notice Response
External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Hi Sue,
Thanks for talking with us last week about the Airport and some of your additional concerns regarding the detention
basins.
We've been able to loop in the airport and I am currently revising the plan with the goal of providing it to the airport later
this week or early next week. We want to make sure they are comfortable with the commitment and to begin the process
of training and/or identifying a resource that can assist them with the monitoring.
Once we have their buyoff, I will provide to you for review.
Thanks!
Kelly
Kelly Thames, Pws
D 704.338.6710 M 704.996.9986
hdrinc.com/follow-us fhdrinc.coml
From: Thames, Kelly
Sent: Thursday, July 2, 2020 9:08 AM
To: 'Homewood, Sue' <[e-mail]>
Cc: 'Shaeffer, David Leigh (Dave) CIV USARMY CESAW (USA)' <[e-mail]>
Subject: RE: [External] CLT Airport Public Notice Response
Ok, thank you, just let me know what I can do!
Kelly Thames, Pws
D 704.338.6710 M 704.996.9986
hdrinc.com/follow-us fhdrinc.coml
From: Homewood, Sue [mailto:[e-mail]]
Sent: Thursday, July 2, 2020 9:04 AM
To: Thames, Kelly <[e-mail]>
Cc: 'Shaeffer, David Leigh (Dave) CIV USARMY CESAW (USA)' <[e-mail]>
Subject: RE: [External] CLT Airport Public Notice Response
CAUTION: [EXTERNAL] This email originated from outside of the organization. Do not click links or open attachments
unless you recognize the sender and know the content is safe.

Hi Kelly,
I wanted to let you know that I reviewed your addinfo response but I need to follow up with Olivia and I want to talk to
David before I get back to you.
Sue Homewood
Division of Water Resources, Winston Salem Regional Office
Department of Environmental Quality
336 776 9693 office
336 813 1863 mobile
[e-mail]
450 W. Hanes Mill Rd, Suite 300
Winston Salem NC 27105
From: Homewood, Sue <[e-mail]>
Sent: Monday, June 29, 2020 10:04 PM
To: Thames, Kelly <[e-mail]>
Cc: 'Shaeffer, David Leigh (Dave) CIV USARMY CESAW (USA)' <[e-mail]>
Subject: Re: [External] CLT Airport Public Notice Response
Sorry. My schedule was derailed by rule re -writes that I didn't know would need my involvement last week. I'm trying to
get back on track this week but have meetings and piles of emails.
Get Outlook for iOS [naml2.safelinks.protection.outlook.com
From: Thames, Kelly <[e-mail]>
Sent: Monday, June 29, 2020 9:48:12 AM
To: Homewood, Sue <[e-mail]>
Cc: 'Shaeffer, David Leigh (Dave) CIV USARMY CESAW (USA)' <[e-mail]>
Subject: RE: [External] CLT Airport Public Notice Response
External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
[e-mail]
Sue,
Let me know about the below when you get to it. Dave reviewed the response and doesn't have any objections. The next
step is for me to update his EA with the information in the response.
However, I don't want to begin until we've heard from you!
Thanks,
Kelly
Kelly Thames, Pws
D 704.338.6710 M 704.996.9986
hdrinc.com/follow-us fhdrinc.coml [nam12.safelinks. protection. outlook.coml

From: Thames, Kelly
Sent: Friday, June 19, 2020 8:06 AM
To:'Homewood, Sue' <[e-mail]>
Subject: RE: [External] CLT Airport Public Notice Response
Thanks for the update!
Kelly Thames, Pws
D 704.338.6710 M 704.996.9986
hdrinc.com/follow-us fhdrinc.comlfnam12.safelinks.protection.outlook.coml
From: Homewood, Sue [mailto:[e-mail]]
Sent: Thursday, June 18, 2020 1:20 PM
To: Thames, Kelly <[e-mail]>
Subject: RE: [External] CLT Airport Public Notice Response
CAUTION: [EXTERNAL] This email originated from outside of the organization. Do not click links or open attachments
unless you recognize the sender and know the content is safe.
Hi. It's next on my review list but I have some other commitments to finish up right now. I expect I'll get a chance to
look at it sometime next week.
Sue Homewood
Division of Water Resources, Winston Salem Regional Office
Department of Environmental Quality
336 776 9693 office
336 813 1863 mobile
Sue. [e-mail]
450 W. Hanes Mill Rd, Suite 300
Winston Salem NC 27105
x 1: - .
ti... x... t x.t x. +xt ..+x.. ;x.... x x.., .... .+.. xx.+ . x....t x t x. ..x.:�.
+., 3 3 ,T�° a ...# ...,, €.rh*a ++,:.
..:. ..r ... ,.. . ,...... ,... a t ...
From: Thames, Kelly <[e-mail]>
Sent: Thursday, June 18, 2020 1:08 PM
To: Homewood, Sue <[e-mail]>
Cc:'Shaeffer, David Leigh (Dave) CIV USARMYCESAW (USA)' <[e-mail]>
Subject: [External] CLT Airport Public Notice Response
•17EExternal email. Do
[e-mail]
Hi Sue,
attachment to
I wanted to check in and see if you had any questions or comments regarding the public notice response for the Airport?
My goal is to stay on top of it for the Airport's schedule!
4

Thanks!
Kelly Thames, Pws
Environmental Project Manager
HDR
440 S. Church Street, Suite 1000
Charlotte, NC 28202-2075
D 704.338.6710 M 704.996.9986
kelly.thames(a)_hdrinc.com
hdrinc.com/follow-us fhdrinc.coml fnaml2.safelinks.protection.outlook.coml fnaml2.safelinks.protection.outlook.coml

Appendix E
Monitoring Plan

CLT Airport Expansion I SAW-2018-01071
In -Line Detention Monitoring Plan
July 17, 2020
Proposed Monitoring Plan
Introduction
The City of Charlotte — Aviation Department (Applicant) submitted a Department of the Army Phased
Individual Permit (IP) on January 31, 2020, for the proposed expansion of the Charlotte Douglas
International Airport (CLT or Airport) in Mecklenburg County, North Carolina. A component of the Phased
I proposes stormwater detention in -line with existing channels. During the Public Notice period, the
United States Army Corps of Engineers (USACE) and the North Carolina Department of Environmental
Quality (NCDEQ) Division of Water Resources (DWR) requested a monitoring plan of those channels
subject to in -line detention.
In the application, in -line detentions are proposed on Ticer Branch (Stream 1 [S1]) for the North End
Around Taxiway (NEAT) element and on Coffey Creek (S25) for the South Crossfield Taxiway (SCF)
element. The purpose of an in -line detention is to provide peak discharge reduction for storm events up to
the 100 year event. Both in -line detentions propose permanent impacts as a result of a culvert and berm
that would be sized to reduce peak flows downstream. For purposes of analysis storm frequencies
modeled include the 2-, 10-, 25-, 50-, and 100-year storm events. Additionally, each detention basin also
proposes a culverted stream crossing for road access within a basin for construction and maintenance.
During the design storm event, the streams would overtop their banks and flood the detention area (i.e.
the stream's floodplain) for stormwater detention, but attenuate within 48 hours. Beyond the culvert and
berm and access road culvert in each basin, no other direct impacts as a result of the in -line detention are
proposed to the stream channels. However, the streamside areas of both Ticer Branch and Coffey Creek
would require an earthen embankment, grading, and removal of trees in order to provide the capacity
necessary to detain the designed storm event. A 10-foot vegetated buffer along each stream will be
maintained.
In the Ticer Branch in -line detention, S1 and S2 are proposed to experience flooding of streamside area.
In the Coffey Creek in -line detention, S25, S32, and S34 are proposed to experience flooding of
streamside area. All five channels will require monitoring per the USACE and DWR request.
Monitoring Locations
The location and number of monitoring locations within both the Ticer Branch and Coffey Creek detention
areas and one monitoring location downstream of each detention basin will be identified. These locations
will be submitted to the DWR prior to baseline monitoring implementation. For the Ticer Branch detention
basin, this location will be located downstream of the detention, but before Ticer Branch enters a culvert
that goes beneath 1-485. For the Coffey Creek detention basin, this location will be downstream of the
detention but upstream of the next downstream stream confluence. Permanent monitoring locations will
be field located using GPS grade accuracy, and set prior to construction by setting permanent
monuments on both stream banks to facilitate comparison of data collected during future monitoring
events.
Monitoring locations within the detention basins will be subject to dimension, substrate, Bank Erosion
Hazard Index (BEHI), and NCSAM assessments, as well as photographic documentation. Monitoring
locations downstream of the detention basins will be subject to substrate and Bank Erosion Hazard Index
(BEHI), as well as photographic documentation.
Page 1 1

CLT Airport Expansion I SAW-2018-01071
In -Line Detention Monitoring Plan
July 17, 2020
All monitoring locations are subject to baseline pre- and post -construction events. The monitoring
locations within the detention basins will be subject to both the annual and quarterly monitoring events.
The monitoring locations downstream of the detention basins will be monitored on a quarterly basis only,
within 30 days of a 2-year storm event (defined as a rain event of at least 2 inches within 6 continuous
hours).
Timing/Frequency
BASELINE MONITORING
The baseline monitoring events will take place pre -construction and post -construction. The purpose of the
pre -construction event is to capture existing conditions of streams subject to detention. The post -
construction event is to document any changes between pre -construction and post -construction and
construction conditions; ideally, the post -construction conditions of streams would be the same as
existing conditions pre -construction with the exception of the streamside areas being converted to
detention areas. If a 2-year storm occurs between the pre -construction and post -construction events, it
should be documented and noted that the post -construction baseline would capture any changes from
said storm event prior to the detentions becoming operational. The data collected immediately following
construction would be expected to be representative of conditions that subsequent monitoring events
would be compared to, taking into account normal stream dynamics and fluctuation.
Baseline monitoring event data collection will include dimension, substrate, Bank Erosion Hazard Index
(BEHI), and NCSAM assessments, as well as photographic documentation.
ANNUAL MONITORING
Annual monitoring events will be held on an annual basis for a period of five years post -construction of
both the Ticer Branch and the Coffey Creek detention basins. The first annual monitoring event shall
occur six months after the post -construction baseline event occurs. If at the end of the five year period of
monitoring, the results during the monitoring events have not significantly changed since the post -
construction baseline condition, then the annual monitoring requirements shall be successfully satisfied.
Annual monitoring event data collection will include dimension, substrate, Bank Erosion Hazard Index
(BEHI), and NCSAM assessments, as well as photographic documentation.
QUARTERLY MONITORING
On a quarterly basis, monitoring shall occur within 30 days following the first 2-year storm event of the
respective quarter up to two years. Only one monitoring event per quarter per 2-year storm event is
necessary. If a 2-year storm event does not occur, then monitoring during that respective quarter is not
required. If at the end of the two year period of quarterly monitoring, the results during the monitoring
events have not significantly changed since the post -construction baseline condition, then the quarterly
monitoring requirements shall be successfully satisfied.
Quarterly monitoring event data collection will include substrate and BEHI assessments, as well as
photographic documentation.
Methods
DIMENSION ASSESSMENT
Dimensional data will be collected based on The Key to the Rosgen Stream Classification of Natural
Rivers which is a classification system that assigns a channel type based on channel slope, width to
depth ratio, bed material, entrenchment ratio, and sinuosity. Permanent cross section monitoring will be
conducted at one or more riffle features that are established during the baseline monitoring events on
Page 12

CLT Airport Expansion I SAW-2018-01071
In -Line Detention Monitoring Plan
July 17, 2020
each channel subject to in -line detention. A stream classification type will be determined at each cross
section during the baseline events as well as subsequent monitoring events. Graphical representations of
cross sections will be provided and as data is collected year to year, the graphical representations will be
overlaid to each other for comparison.
Data collected in dimensional assessment will be presented as a list of parameters (Table 1) resulting in a
Rosgen Classification channel type, which represents the measure of all dimension assessment
parameters. Classifying a channel type based on Rosgen methodology on an annual basis allows for
observation in shifts of channel geomorphology, if any. Geomorphological evolution is a natural channel
process, that when observed, doesn't necessarily indicate channel degradation, but does provide insight
as to whether or not a channel is widening, incising, straightening, or experiencing sediment loading
based on the measured parameters.
The Rosgen Classification channel type is not expected to significantly change from baseline conditions;
however, if channel type changes do occur, then it would be expected that one or more parameter has
significantly been altered from the baseline channel classification type. Further analysis of the individual
parameters (i.e. substrate) would need to be evaluated to determine if degradation has occurred.
SUBSTRATE
A Wolman pebble count is a characterization of the composition of streambed and bank substrate
material. Monitoring substrate during monitoring events can indicate changes in stream character, erosion
rates, and sediment supply. Wolman pebble counts categorize substrate types into silt/clay, sands,
gravels, cobbles, boulders, and bedrock, which are sub -categorized within the substrate types based on
diameter size. The data collected from a substrate sample can be analyzed by sizes (diameter in mm)
and by distribution of size. For example, D50 is the median diameter of a substrate sample and also the
diameter size at which 50% of the substrate particles are smaller and 50% of the substrate particles are
larger than the mean diameter distributed across a sample.
Wolman pebble count methodology will be utilized to calculate the D50 of the stream bed material to
establish baseline particle size and distribution at the permanent cross -sections to aid in determining
Rosgen classification channel type. The post -construction baseline D50 will also be the parameter to
which future substrate analysis would be compared. If future substrate monitoring indicates a trend of the
D50 shifting to a smaller particle size diameter (by more than 20% of original size) after three substrate
monitoring events, then DWR will be notified and remedial actions will be evaluated for consideration.
BANK EROSION HAZARD INDEX
While stream bank erosion is a natural process that occurs in every watershed, excessive erosion has
serious adverse consequences for the physical and biological function of streams and rivers. It is often
difficult, however, to distinguish between streambanks that are eroding at a natural rate from those that
are or have the potential to erode at unnaturally high rates due to altered watershed hydrology or
sediment loads. The Bank Erosion Hazard Index (BEHI) is a methodology for assessing streambank
erosion condition and potential that assigns point values to bank condition. BEHI will be assessed utilizing
the modified BEHI procedure that includes ratios of root depth to bank height, root density in percentage,
surface protection in percent, and bank angle in degrees.
The BEHI scoring falls into six categories ranging from Very Low to Extreme. In reference to the post -
construction baseline BEHI scores, if future monitoring events produce a BEHI score two categories
greater than the baseline from three subsequent events, then DWR will be notified and remedial actions
will be evaluated for consideration. DWR will be contacted if the baseline score is "Extreme", for further
discussion and possible procedure modification.
Page 13

FN CLT Airport Expansion I SAW-2018-01071
In -Line Detention Monitoring Plan
July 17, 2020
NORTH CAROLINA STREAM ASSESSMENT METHODOLOGY
The North Carolina Stream Assessment Methodology (NCSAM) will be utilized to assess stream quality
and function at each cross section. The assessment length at each cross section will be 100 feet
upstream and downstream of the cross section location. The NCSAM method provides for an evaluation
of streamside riparian vegetation as well as a field assessment of hydrological influence, water quality,
and biology within a reach. However, due to the nature of the detention construction, the streamside
areas will be cleared of trees with the exception of a 10-foot vegetated buffer. The NCSAM assessments
should take into consideration the NCSAM matrices that assess vegetated buffer parameters so that the
detention construction itself does not influence the NCSAM scores.
PHOTOGRAPHIC DOCUMENTATION
Photographs looking upstream and downstream at each monitoring location will be taken during the
baseline monitoring to visually document the existing conditions of the channels. Photographs will also be
taken post -construction, and at annual and quarterly monitoring events. Photographs will be provided in
both the annual and quarterly reports, but will also be displayed side by side over time as the
photographs are collected.
Summary
The proposed monitoring plan for the channels subject to in -line detention will consist of multiple
measurements and assessments noted above that will provide a way to track the geomorphology,
substrate, stability, and quality of the channels over time. Pre- and post -construction baseline conditions
will be presented with a short cover letter and report of findings will be provided to the USACE and DWR
for review. Subsequently, after each annual and quarterly monitoring event, a short cover letter and report
of findings will be provided for review.
At each cross section identified within the detention basins, dimensional data, substrate characterization,
NCSAM, BEHI will be assessed and described above. A variation of the following table will be utilized to
report baseline, annual, and quarterly data at each cross-section. At each monitoring location identified
downstream of the detention basins, substrate characterization and BEHI will be assessed and described
above.
Table 1. Example Table for Assessment Data
Stream # Stream # Stream #
Cross Section # Cross Section # Cross Section #
Bankfull Width (ft)
Floodprone Width (ft)
Bankfull Mean Depth (ft)
Bankfull Max Depth (ft)
Bankfull Cross Sectional Area (ft')
Width/Depth Ratio
Entrenchment Ratio
Dso (mm)
Rosgen Classification
NCSAM Score
BEHI
Page 14

FN
CLT Airport Expansion I SAW-2018-01071
In -Line Detention Monitoring Plan
July 17, 2020
A variation of the following table will be utilized to report overall data after each collection event over time.
Table 2. Example Table of Results Summary
Year
mkiClass
Rosgen D5o NCSAM BEHI Rosgen p5o NCSAM BEHI Rosgen p5o NCSAM BEHI Class Class
Stream # #
Stream # #
Stream # #
Stream # #
Methodology References
The Key to the Rosgen Stream Classification of Natural Rivers:
https://wiIdlandhydrology.com/resources/docs/River%20Restoration%20and%20Natural%20Channel%20
Design/Rosgen 2011 Natural Channel Design.pdf
Wolman Pebble Count:
https://dep.wv.gov/WWE/getinvolved/sos/Documents/SOPs/PebbleCount Methods.pdf
Bank Erosion Hazard Index:
https://dep.wv.gov/WWE/getinvolved/sos/Documents/SOPs/BEH I -Overview. pdf
North Carolina Stream Assessment Methodology:
https://www.saw.usace.army.miI/Portals/59/docs/regulatorv/publicnotices/2013/NCSAM Draft User Man
ual 130318.pdf
Page 15