20000846 Ver 1_Stormwater Info_20060101

Michael Baker Jr., Inc.
A Unit of Michael Baker Corporation
19 October 2001
P.O. Box 12259
Pittsburgh, Pennsylvania 15231-0259
[phone]
Ms. Cyndi Karoly FAX [phone]
North Carolina Department Office Location:
of Environmental and Natural Resources Airport Office Park, Building 3
420 Rouser Road
1617 Mail Service Central Coraopolis, Pennsylvania 15108
Raleigh, NC 27699-1617
Subject: Piedmont Triad Airport Authority - Stormwater Management Plan Version 1.0
Update Number 1
Dear Ms. Karoly:
Enclosed is Update Number 1 to the Stormwater Management Plan Version 1.0. This update
should be posted in your copy of the Stormwater Management Plan along with this transmittal
letter. Your copy of the Plan are numbers 1 and 2.
This update provides a final copy of Section 7.0 Storm Water Plan for Deep River (Randleman
Lake) Watershed.
Section 7.0 includes:
1. Certificate of Adoption
2. Resolution Adopting Randleman Lake Storm Water Management Plan
3. Pages 7-1 through 7-8
4. Deep River High Point Watershed Map
As updates are published, a copy will be forwarded to your attention.
Sincerely,
BAKER AND ASSOCIATES
Allan R. Berenbrok, P.E.
Project Manager
OCT 3 0 2001
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CERTIFICATE OF ADOPTION
I certify that I am the Secretary of the Piedmont Triad
Airport Authority and that at a meeting duly called and held on
August 21, 2001, the attached resolution and accompanying "Sto=
Water Plan for Deep River (Randleman Lake) Watershed" were duly
adopted by said Authority.
This the '71 day of August, 2001
Authority
F t ?
F OCT 3 0 2001
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4k
Resolution Adopting Randleman Lake Storm Water Management Plan
WHEREAS, under 15A NCAC 213; 0251 of the North Carolina Code of Regulations, local
governments having land in the Randleman Lake Watershed, including the Authority, must
adopt a comprehensive storm water management plan, that is approved by the North Carolina
Environmental Management Commission, for the portion of their jurisdiction that is within
the watershed boundary and;
WHEREAS, the staff of the Authority has developed a proposed plan in accordance with the
state regulations entitled A Storm Water Plan for the Deep River (Randleman Lake)
Watersheds @ (the AProposed Plan@), a copy of which has been furnished to each of the
members of the Authority, and such plan has been approved on behalf of the North Carolina
Environmental Management Commission by its Water Quality Committee; and
WHEREAS, the adoption and implementation of the Proposed Plan would fulfill the
Authority's obligations under the applicable regulations, would promote good watershed
management of the portion of the Randleman Lake Watershed that is within the Authority's
jurisdiction, and would help to improve water quality within the Randleman Lake Watershed
and the Randleman Lake Reservoir now under construction;
NOW, THEREFORE, BE IT RESOLVED by the Piedmont Triad Airport Authority that the
Proposed Plan is hereby approved and adopted as the Randleman Lake Storm Water
Management Plan of the Authority in accordance with 15A NCAC 2B. 0251 and that the
officers and staff of the Authority are hereby directed to Implement such plan in accordance
with its terms.
August, 2001 Section 7 Resolution Randleman Lake
7.0 Storm Water Plan for Deep River (Randleman Lake) Watershed
Under 15A NCAC 2B. 0251 (4), local governments with land use authority within the
proposed Randleman Lake Watershed are required to adopt comprehensive storm water
management plans for the portion of the watershed that is under their jurisdiction. The Deep
River, High Point Watershed, as described in this SWMP, and as shown on the Watershed
Map that appears at the end of this Section, is a part of the larger Randleman Lake
Watershed, and PTAA is therefore required by 15A NCAC 2B.0251(4) to adopt a
comprehensive storm water plan for the portion of the Airport that is within this area. This
Section 7 sets forth the plan the PTAA has adopted. It is intended as a supplement to the rest
of this SWMP, and applies only to land within the Deep River, High Point Watershed that
PTAA presently owns or acquires in the future.
The regulations describe six separate components to be included in the plan. The applicable
requirements of the regulations, and the corresponding provisions of PTAA's plan, are as
follows:
Evaluation of Existing Land Use
Regulation:
(a) Evaluation of existing land use within Oak Hollow Lake subwatershed, High Point
Lake subwatershed and Deep Riverl subwatershed in the Randleman Lake Watershed
with recommendations that show how overall built-upon area (for existing and future
development) for each subwatershed can be minimized and high intensity land uses
can be targeted away from surface waters and sensitive areas. Oak Hollow Lake
subwatershed is defined as all land areas draining to Oak Hollow Lake. High Point
Lake subwatershed is defined as all land areas draining to High Point Lake, East Fork
Deep River and West Fork Deep River from Oak Hollow Lake Dam. Deep River 1
subwatershed is defined as all land areas draining to the Deep River from High Point
Lake Dam to Freeman Mill Dam. This evaluation shall be done by the local
governments having jurisdiction in those watersheds, working in cooperation with the
PTRWA.
Goal:
Evaluate and possibly modify existing land use plans and development patterns to
achieve better protection of the Randleman Lake Watershed.
August, 2001 Section 7-Page 1 Randleman Lake

Action Items:
The Watershed Map appearing at the end of this Section identifies three separate
zones within the Deep River, (Randleman Lake) Watershed, for planning purposes, as
follows:
¦ Zone 1: Zone 1 consists of the Runway Protection Zone (RPZ) in the approach to
existing Runway 5R, as shown on the map, plus some adjoining land outside of
the RPZ. PTAA owns most of the land within Zone 1 as shown on the map. The
land that is owned by PTAA within Zone 1 is presently undeveloped, except for
an instrument landing system, other navigational aids, and a gravel service road.
¦ Zone 2: Zone 2 consists of all of the land that is owned by PTAA within the
Randleman Lake Watershed that is not within Zone 1 or Zone 3. Zone 2 includes
major airport facilities, including a portion of Runway 14-32 and associated
taxiways, an air cargo building and major aircraft hangars. PTAA is presently
relocating its Maintenance Building within Zone 2.
¦ Zone 3: Zone 3 is located at the southwest end of proposed Runway 5L-23R. It
will consist of the portion of the RPZ for the proposed runway north of the right-
of-way of U.S. 421 and east of the right-of-way for U.S. 68, plus some additional
land adjacent to the RPZ. PTAA now owns a portion of the land within Zone 3
and may acquire additional land within Zone 3 in the future. At present, Zone 3
contains extensive commercial and light industrial development. The Watershed
Map shows the boundaries of Zone 3 based on the RPZ and runway location that
is currently proposed by the PTAA. If the location of the RPZ changes in the
final design of the runway, Zone 3, as referred to in this Plan, will coincide with
the revised RPZ plus the adjacent land shown on the Map.
There are three water bodies within the Airport portion of the Randleman Lake
Watershed as shown on the U.S.G.S. Topographic Map ("Guilford, N.C." revised
1994) for the area: (1) a stream along the southeast boundary of Zone 1, (2) a pond on
the northwest side of Zone 3 and (3) a stream, also within Zone 3, below the pond.
These streams are ephemeral.
PTAA's plan for meeting the requirements of this portion of the Randleman Lake
Regulations is as follows:
1. PTAA's goal is to direct future development within its portion of the Randleman
Lake Watershed primarily to Zone 2.
2. PTAA plans to demolish a portion of the existing development within Zone 2, in
the vicinity of the proposed runway, as well as a portion of the existing
development within Zone 3, including warehouses and adjacent parking areas
August, 2001 Section 7-Page 2 Randleman Lake

within those zones. As a result of this demolition, approximately 20 acres of
existing Built Upon Area will actually be removed and will be replaced with
natural ground cover.
3. The only new development that is currently planed by PTAA within Zone 1 is an
upgrade of the instrument approach to Runway 5R. If PTAA decides in the future
to undertake any other development within Zone 1, it will comply with FAA
restrictions that apply to the Runway Protection Zone (RPZ) in the approach to
the runway. (The limits of the RPZ are shown on the Watershed Map.) These
restrictions prohibit residential development, places of public assemblage, and
fuel storage facilities from being relocated within an RPZ.
4. Subject to the issuance by the FAA of a favorable Record of Decision and to the
satisfaction of certain other conditions, PTAA presently plans to construct a
proposed Runway 5R-23L and to establish the RPZ for the new runway. If the
new runway is constructed, the only development currently planned by PTAA
within its portion of Zone 3 is the installation of an instrument approach system
for the new runway, other navigational aids, and a service road. If PTAA decides
in the future to undertake any other development within Zone 3, PTAA will
comply with the FAA restrictions on development within the new RPZ; and
PTAA will also maintain on Object Free Area, 800 feet wide, running the entire
length of the runway and extending 1000 feet beyond the runway end. Additional
Object Free Areas will be required for each taxiway. Although there are no
current plans for doing so, PTAA may in the future extend the new runway to the
southwest, but in such case the Object Free Area and RPZ for the runway would
also be extended in that direction.
This plan applies only to land that is owned by the PTAA within Zones 1 - 3 and not
to any land that is owned by other parties. If PTAA acquires additional land within
Zones 1 -3 in the future, the additional land will become subject to this plan at the
time of its acquisition.
The foregoing plan will not only minimize Built Upon Area within the Watershed,
but will actually reduce Built Upon Area, in and around Zone 3, by approximately 20
acres. By establishing a goal of concentrating new development primarily in Zone 2,
the plan will also target high intensity land uses away form surface waters and
sensitive areas because the only water bodies within PTAA's portion of the
Watershed are located in Zones 1 and 3.
In carrying out the foregoing plan, PTAA will cooperate with the PTRWA by
attending the annual update meetings for which it receives notice or is otherwise
aware among the PTRWA and the local government units having territory within the
Randleman Lake Watershed.
August, 2001 Section 7-Page 3 Randleman Lake
Coordinated Planning Efforts
Regulation:
(b) Coordination between all affected jurisdictions to encourage their development in the
existing urban areas. The planning effort shall include provisions for areas of
contiguous open space to be protected through conservation easements or other long-
term protection measures and provisions to direct infrastructure growth towards
existing urban development corridors rather than to rural lands.
Goal:
To achieve greater watershed protection and efficiency through regional coordination
among the jurisdictions in the Randleman Lake Watershed.
Action Items:
PTAA's goal of locating new development primarily in Zone 2, will help to
concentrate development in the areas in which it already exists and to divert
development away from the open space that is owned by PTAA within Zone 1 and
away from the area that will be restored to natural growth in Zone 3. Long-term
protection measures will be imposed for all of these areas by PTAA's maintenance of
the RPZ for the Runway 5R approach, by PTAA's establishment of an RPZ for the
Runway 5L approach, and by the creation of the Object Free Areas for the new
runway and taxiways, as described above. These protections will remain in effect for
as long as the runways are operational. These restrictions will help to protect the
open areas within Zones 1 and 3 and improve storm water quality within these Zones.
PTAA will cooperate with the other jurisdictions within the Randleman Lake
Watershed by attending the annual update meetings sponsored by the PTRWA, as
stated above. PTAA will also assist the efforts of adjoining jurisdictions to develop
land use plans that are compatible with airport development for areas outside the
Airport boundaries, including plans for the maintenance of open space, where
appropriate.
August, 2001 Section 7-Page 4 Randleman Lake
Evaluation of Existing Ordinances
Regulation:
(c) Evaluation of existing ordinances, municipal programs (maintenance, street cleaning,
etc.) and other local policies to identify opportunities for storm water quality
improvements including reducing the amount of built-upon area that is required for
uses such as parking, building set-backs, road widths and cul-de-sacs. The
evaluations shall consider development options such as multiple story buildings,
mixed use to encourage pedestrian travel and mass transit and an identification of
municipal activities and procedures that may be modified to allow for storm water
pollution prevention opportunities.
Goal:
To identify opportunities to fine tune existing ordinances and policies so as to achieve
better quality in the Randleman Lake Watershed.
Action Items:
PTAA is restricted in its ability to alter land use requirements by FAA development
standards, such as height and setback requirements, and by PTAA's obligation to
conform to Airport Layout Plan that is approved for the Airport by the FAA.
However, PTAA will attempt to achieve storm water quality improvements as
follows:
1. In undertaking new development projects within the Randleman Lake
Watershed, PTAA will investigate design alternatives that reduce new Built
Upon Area.
2. In grading areas within the Randleman Lake Watershed, PTAA will attempt to
control soil erosion and sedimentation by phasing grading operations, and by
accelerating the establishment new ground cover over graded areas, so as to
reduce the time that unprotected areas are exposed to erosion.
3. All new development projects that are undertaken by PTAA throughout the
Airport, including Zones 1 - 3, will comply with the watershed protection
requirements set forth in PTAA's Watershed Ordinance and this SWMP
unless a valid Variance is granted under the procedures set forth in the
Ordinance. Pursuant to the Watershed Ordinance, PTAA has elected to apply
high density criteria to all new development projects resulting in a new Built
Upon Area of more than five acres. This requirement is in excess of the state
minimum requirements because the Built Upon Percentage at the Airport is
less than 241/0, and therefore PTAA could have elected to apply low-density
August, 2001 Section 7-Page 5 Randleman Lake
criteria to all new development at the Airport. As a result of the election made
by PTAA, engineered storm water controls will be required for all projects in
excess of the five-acre limit. The Watershed Ordinance also requires that new
development projects resulting in new Built Upon Area of five acres or less be
designed, to the maximum extent practicable, to minimize Built Upon Area, to
direct storm water runoff away from surface waters, and to incorporate Best
Management Practices to minimize water quality impacts. A Watershed
Protection Plan will be required for all new development projects (regardless
of size) showing how the applicable criteria will be met. These requirements
will greatly reduce the impact of any new development that does occur within
the Randleman Lake Watershed.
4. PTAA will implement a Spill Prevention Control and Countermeasure Plan
(SPCCP) that will establish procedures to help prevent, control and remediate
spills of oil or hazardous materials at the Airport.
Public Education Programs
Regulation:
(e) Implementation of watershed protection public education programs.
Goal:
To educate the community about impacts of storm water discharge on water bodies
and what is needed to reduce storm water pollution in the Randleman Lake
Watershed.
Action Items:
There is no population living within the portion of the Airport that leis within the
Randleman Lake Watershed. However, PTAA will undertake, through distribution of
this SWMP and PTAA's SPCCP, to educate Airport tenants concerning the impacts
of storm water discharge and the actions that are necessary to improve storm water
quality at the Airport. PTAA will also make a presentation to Airport tenants, upon
the final adoption of this SWMP, of the requirements of the plan and of the SPCCP,
and of the impact of storm water discharge on water quality. PTAA will also explore
the possibility of participating in a multi jurisdictional interlocal agreement to meet
the educational requirements of the Randleman Rules. The proposed interlocal
agreement would allow the communities to cooperate in the creation and
dissemination of educational material that would educate the community about the
effects of storm water pollution on our limited water resources.
August, 2001 Section 7-Page 6 Randleman Lake
Identification and Removal of Illegal Discharges
Regulation:
(e) Identification and removal of illegal discharges.
Goal:
To improve water quality through the identification and removal of illegal discharges
within the Randleman Lake Watershed.
Action Items:
Through the implementation of its SPCCP, PTAA will attempt to locate areas at the
Airport form which an illegal discharge might occur and to identify the storm water
outlet that would be affected.
PTAA also anticipates the issuance of an NPDES permit to PTAA, in which Airport
tenants will be named a co-permittees, with respect to storm water discharge at the
Airport. The permit is expected to require periodic monitoring of storm water outfalls
at the Airport for various substances, including oil and hazardous material.
If an illegal discharge is identified by PTAA on PTAA property within the
Randleman Lake Watershed, PTAA will attempt to determine the source. If PTAA's
own activities are the source of the discharge, the discharge will be discontinued. If
the discharge results from a source other than PTAA, such as a PTAA tenant, PTAA
shall take such reasonable actions as it shall determine, within its authority, to assist
in the removal of the discharge. PTAA will also include in all new lease agreements
that it enters into with its tenants a requirement that, upon discovery by the tenant or
the receipt of notification, the tenant will take such remedial actions as may be legally
required with respect to any illegal use or release of hazardous materials by the tenant
on PTAA property.
Identification of Potential Storm Water Retrofit Locations
Regulation:
(f) Identification of suitable locations for potential storm water retrofits (such as riparian
areas) that could be funded by various sources.
Goal:
To develop a process to identify and plan for storm water retrofits in the Randleman
Lake Watershed.
August, 2001 Section 7-Page 7 Randleman Lake
y
Action Items:
The removal of existing Built Upon Area from Zone 3 and surrounding land, as
described above, will result in the restoration of natural ground cover, including grass and
low shrub-type vegetation. (Tall growing trees will not be permitted within the RPZ in the
approach to Runway 5L). In grading the previously developed land, PTAA will develop a
series of meandering grass swales. A grass Swale is noted by the NCDENR in its publication
of Best Management Practices as potentially removing up to 35% of Total Suspended Solids
(TSS). PTAA will also consider planing grass filter strips below any remaining impervious
surface to filter runoff from these areas. Filter strips are noted by the NCDENR as
potentially removing up to 40% of TSS.
August, 2001 Section 7-Page 8 Randleman Lake
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CERTIFICATE OF ADOPTION
I certify that I am the Secretary of the Piedmont Triad
Airport Authority and that at a meeting duly called and held on
August 21, 2001, the attached resolution and accompanying "Storm
Water Plan for Deep River (Randleman Lake) Watershed" were duly
adopted by said Authority.
This the I( day of August, 2001.
-Secretary,`' Piedmont Triad
Airpor Authority
k
Resolution Adopting Randleman Lake Storm Water Management Plan
WHEREAS, under 15A NCAC 213; 0251 of the North Carolina Code of Regulations, local
governments having land in the Randleman Lake Watershed, including the Authority, must
adopt a comprehensive storm water management plan, that is approved by the North Carolina
Environmental Management Commission, for the portion of their jurisdiction that is within
the watershed boundary and;
WHEREAS, the staff of the Authority has developed a proposed plan in accordance with the
state regulations entitled A Storm Water Plan for the Deep River (Randleman Lake)
Watersheds @ (the AProposed Plan@), a copy of which has been furnished to each of the
members of the Authority, and such plan has been approved on behalf of the North Carolina
Environmental Management Commission by its Water Quality Committee; and
WHEREAS, the adoption and implementation of the Proposed Plan would fulfill the
Authority's obligations under the applicable regulations, would promote good watershed
management of the portion of the Randleman Lake Watershed that is within the Authority's
jurisdiction, and would help to improve water quality within the Randleman Lake Watershed
and the Randleman Lake Reservoir now under construction;
NOW, THEREFORE, BE IT RESOLVED by the Piedmont Triad Airport Authority that the
Proposed Plan is hereby approved and adopted as the Randleman Lake Storm Water
Management Plan of the Authority in accordance with 15A NCAC 2B. 0251 and that the
officers and staff of the Authority are hereby directed to Implement such plan in accordance
with its terms.
August, 2001 Section 7 Resolution Randleman Lake

7.0 Storm Water Plan for Deep River (Randleman Lake) Watershed
Under 15A NCAC 2B. 0251 (4), local governments with land use authority within the
proposed Randleman Lake Watershed are required to adopt comprehensive storm water
management plans for the portion of the watershed that is under their jurisdiction. The Deep
River, High Point Watershed, as described in this SWMP, and as shown on the Watershed
Map that appears at the end of this Section, is a part of the larger Randleman Lake
Watershed, and PTAA is therefore required by 15A NCAC 2B.0251(4) to adopt a
comprehensive storm water plan for the portion of the Airport that is within this area. This
Section 7 sets forth the plan the PTAA has adopted. It is intended as a supplement to the rest
of this SWMP, and applies only to land within the Deep River, High Point Watershed that
PTAA presently owns or acquires in the future.
The regulations describe six separate components to be included in the plan. The applicable
requirements of the regulations, and the corresponding provisions of PTAA's plan, are as
follows:
Evaluation of Existing Land Use
Regulation:
(a) Evaluation of existing land use within Oak Hollow Lake subwatershed, High Point
Lake subwatershed and Deep Riverl subwatershed in the Randleman Lake Watershed
with recommendations that show how overall built-upon area (for existing and future
development) for each subwatershed can be minimized and high intensity land uses
can be targeted away from surface waters and sensitive areas. Oak Hollow Lake
subwatershed is defined as all land areas draining to Oak Hollow Lake. High Point
Lake subwatershed is defined as all land areas draining to High Point Lake, East Fork
Deep River and West Fork Deep River from Oak Hollow Lake Dam. Deep River 1
subwatershed is defined as all land areas draining to the Deep River from High Point
Lake Dam to Freeman Mill Dam. This evaluation shall be done by the local
governments having jurisdiction in those watersheds, working in cooperation with the
PTRWA.
Goal:
Evaluate and possibly modify existing land use plans and development patterns to
achieve better protection of the Randleman Lake Watershed.
August, 2001 Section 7-Page 1 Randleman Lake
Action Items:
The Watershed Map appearing at the end of this Section identifies three separate
zones within the Deep River, (Randleman Lake) Watershed, for planning purposes, as
follows:
¦ Zone 1: Zone 1 consists of the Runway Protection Zone (RPZ) in the approach to
existing Runway 5R, as shown on the map, plus some adjoining land outside of
the RPZ. PTAA owns most of the land within Zone 1 as shown on the map. The
land that is owned by PTAA within Zone 1 is presently undeveloped, except for
an instrument landing system, other navigational aids, and a gravel service road.
¦ Zone 2: Zone 2 consists of all of the land that is owned by PTAA within the
Randleman Lake Watershed that is not within Zone 1 or Zone 3. Zone 2 includes
major airport facilities, including a portion of Runway 14-32 and associated
taxiways, an air cargo building and major aircraft hangars. PTAA is presently
relocating its Maintenance Building within Zone 2.
¦ Zone 3: Zone 3 is located at the southwest end of proposed Runway 5L-23R. It
will consist of the portion of the RPZ for the proposed runway north of the right-
of-way of U.S. 421 and east of the right-of-way for U.S. 68, plus some additional
land adjacent to the RPZ. PTAA now owns a portion of the land within Zone 3
and may acquire additional land within Zone 3 in the future. At present, Zone 3
contains extensive commercial and light industrial development. The Watershed
Map shows the boundaries of Zone 3 based on the RPZ and runway location that
is currently proposed by the PTAA. If the location of the RPZ changes in the
final design of the runway, Zone 3, as referred to in this Plan, will coincide with
the revised RPZ plus the adjacent land shown on the Map.
There are three water bodies within the Airport portion of the Randleman Lake
Watershed as shown on the U.S.G.S. Topographic Map ("Guilford, N.C." revised
1994) for the area: (1) a stream along the southeast boundary of Zone 1, (2) a pond on
the northwest side of Zone 3 and (3) a stream, also within Zone 3, below the pond.
These streams are ephemeral.
PTAA's plan for meeting the requirements of this portion of the Randleman Lake
Regulations is as follows:
1. PTAA's goal is to direct future development within its portion of the Randleman
Lake Watershed primarily to Zone 2.
2. PTAA plans to demolish a portion of the existing development within Zone 2, in
the vicinity of the proposed runway, as well as a portion of the existing
development within Zone 3, including warehouses and adjacent parking areas
August, 2001 Section 7-Page 2 Randleman Lake
within those zones. As a result of this demolition, approximately 20 acres of
existing Built Upon Area will actually be removed and will be replaced with
natural ground cover.
3. The only new development that is currently planed by PTAA within Zone 1 is an
upgrade of the instrument approach to Runway 5R. If PTAA decides in the future
to undertake any other development within Zone 1, it will comply with FAA
restrictions that apply to the Runway Protection Zone (RPZ) in the approach to
the runway. (The limits of the RPZ are shown on the Watershed Map.) These
restrictions prohibit residential development, places of public assemblage, and
fuel storage facilities from being relocated within an RPZ.
4. Subject to the issuance by the FAA of a favorable Record of Decision and to the
satisfaction of certain other conditions, PTAA presently plans to construct a
proposed Runway 5R-23L and to establish the RPZ for the new runway. If the
new runway is constructed, the only development currently planned by PTAA
within its portion of Zone 3 is the installation of an instrument approach system
for the new runway, other navigational aids, and a service road. If PTAA decides
in the future to undertake any other development within Zone 3, PTAA will
comply with the FAA restrictions on development within the new RPZ; and
PTAA will also maintain on Object Free Area, 800 feet wide, running the entire
length of the runway and extending 1000 feet beyond the runway end. Additional
Object Free Areas will be required for each taxiway. Although there are no
current plans for doing so, PTAA may in the future extend the new runway to the
southwest, but in such case the Object Free Area and RPZ for the runway would
also be extended in that direction.
This plan applies only to land that is owned by the PTAA within Zones 1 - 3 and not
to any land that is owned by other parties. If PTAA acquires additional land within
Zones 1 -3 in the future, the additional land will become subject to this plan at the
time of its acquisition.
The foregoing plan will not only minimize Built Upon Area within the Watershed,
but will actually reduce Built Upon Area, in and around Zone 3, by approximately 20
acres. By establishing a goal of concentrating new development primarily in Zone 2,
the plan will also target high intensity land uses away form surface waters and
sensitive areas because the only water bodies within PTAA's portion of the
Watershed are located in Zones 1 and 3.
In carrying out the foregoing plan, PTAA will cooperate with the PTRWA by
attending the annual update meetings for which it receives notice or is otherwise
aware among the PTRWA and the local government units having territory within the
Randleman Lake Watershed.
August, 2001 Section 7-Page 3 Randleman Lake
Coordinated Planning Efforts
Regulation:
(b) Coordination between all affected jurisdictions to encourage their development in the
existing urban areas. The planning effort shall include provisions for areas of
contiguous open space to be protected through conservation easements or other long-
term protection measures and provisions to direct infrastructure growth towards
existing urban development corridors rather than to rural lands.
Goal:
To achieve greater watershed protection and efficiency through regional coordination
among the jurisdictions in the Randleman Lake Watershed.
Action Items:
PTAA's goal of locating new development primarily in Zone 2, will help to
concentrate development in the areas in which it already exists and to divert
development away from the open space that is owned by PTAA within Zone 1 and
away from the area that will be restored to natural growth in Zone 3. Long-term
protection measures will be imposed for all of these areas by PTAA's maintenance of
the RPZ for the Runway 5R approach, by PTAA's establishment of an RPZ for the
Runway 5L approach, and by the creation of the Object Free Areas for the new
runway and taxiways, as described above. These protections will remain in effect for
as long as the runways are operational. These restrictions will help to protect the
open areas within Zones 1 and 3 and improve storm water quality within these Zones.
PTAA will cooperate with the other jurisdictions within the Randleman Lake
Watershed by attending the annual update meetings sponsored by the PTRWA, as
stated above. PTAA will also assist the efforts of adjoining jurisdictions to develop
land use plans that are compatible with airport development for areas outside the
Airport boundaries, including plans for the maintenance of open space, where
appropriate.
August, 2001 Section 7-Page 4 Randleman Lake
Evaluation of Existing Ordinances
Regulation:
(c) Evaluation of existing ordinances, municipal programs (maintenance, street cleaning,
etc.) and other local policies to identify opportunities for storm water quality
improvements including reducing the amount of built-upon area that is required for
uses such as parking, building set-backs, road widths and cul-de-sacs. The
evaluations shall consider development options such as multiple story buildings,
mixed use to encourage pedestrian travel and mass transit and an identification of
municipal activities and procedures that may be modified to allow for storm water
pollution prevention opportunities.
Goal:
To identify opportunities to fine tune existing ordinances and policies so as to achieve
better quality in the Randleman Lake Watershed.
Action Items:
PTAA is restricted in its ability to alter land use requirements by FAA development
standards, such as height and setback requirements, and by PTAA's obligation to
conform to Airport Layout Plan that is approved for the Airport by the FAA.
However, PTAA will attempt to achieve storm water quality improvements as
follows:
1. In undertaking new development projects within the Randleman Lake
Watershed, PTAA will investigate design alternatives that reduce new Built
Upon Area.
2. In grading areas within the Randleman Lake Watershed, PTAA will attempt to
control soil erosion and sedimentation by phasing grading operations, and by
accelerating the establishment new ground cover over graded areas, so as to
reduce the time that unprotected areas are exposed to erosion.
3. All new development projects that are undertaken by PTAA throughout the
Airport, including Zones 1 - 3, will comply with the watershed protection
requirements set forth in PTAA's Watershed Ordinance and this SWMP
unless a valid Variance is granted under the procedures set forth in the
Ordinance. Pursuant to the Watershed Ordinance, PTAA has elected to apply
high density criteria to all new development projects resulting in a new Built
Upon Area of more than five acres. This requirement is in excess of the state
minimum requirements because the Built Upon Percentage at the Airport is
less than 24%, and therefore PTAA could have elected to apply low-density
August, 2001 Section 7-Page 5 Randleman Lake
criteria to all new development at the Airport. As a result of the election made
by PTAA, engineered storm water controls will be required for all projects in
excess of the five-acre limit. The Watershed Ordinance also requires that new
development projects resulting in new Built Upon Area of five acres or less be
designed, to the maximum extent practicable, to minimize Built Upon Area, to
direct storm water runoff away from surface waters, and to incorporate Best
Management Practices to minimize water quality impacts. A Watershed
Protection Plan will be required for all new development projects (regardless
of size) showing how the applicable criteria will be met. These requirements
will greatly reduce the impact of any new development that does occur within
the Randleman Lake Watershed.
4. PTAA will implement a Spill Prevention Control and Countermeasure Plan
(SPCCP) that will establish procedures to help prevent, control and remediate
spills of oil or hazardous materials at the Airport.
Public Education Programs
Regulation:
(e) Implementation of watershed protection public education programs.
Goal:
To educate the community about impacts of storm water discharge on water bodies
and what is needed to reduce storm water pollution in the Randleman Lake
Watershed.
Action Items:
There is no population living within the portion of the Airport that leis within the
Randleman Lake Watershed. However, PTAA will undertake, through distribution of
this SWMP and PTAA's SPCCP, to educate Airport tenants concerning the impacts
of storm water discharge and the actions that are necessary to improve storm water
quality at the Airport. PTAA will also make a presentation to Airport tenants, upon
the final adoption of this SWMP, of the requirements of the plan and of the SPCCP,
and of the impact of storm water discharge on water quality. PTAA will also explore
the possibility of participating in a multi jurisdictional interlocal agreement to meet
the educational requirements of the Randleman Rules. The proposed interlocal
agreement would allow the communities to cooperate in the creation and
dissemination of educational material that would educate the community about the
effects of storm water pollution on our limited water resources.
August, 2001 Section 7-Page 6 Randleman Lake
Identification and Removal of Illegal Discharges
Regulation:
(e) Identification and removal of illegal discharges.
Goal:
To improve water quality through the identification and removal of illegal discharges
within the Randleman Lake Watershed.
Action Items:
Through the implementation of its SPCCP, PTAA will attempt to locate areas at the
Airport form which an illegal discharge might occur and to identify the storm water
outlet that would be affected.
PTAA also anticipates the issuance of an NPDES permit to PTAA, in which Airport
tenants will be named a co-permittees, with respect to storm water discharge at the
Airport. The permit is expected to require periodic monitoring of storm water outfalls
at the Airport for various substances, including oil and hazardous material.
If an illegal discharge is identified by PTAA on PTAA property within the
Randleman Lake Watershed, PTAA will attempt to determine the source. If PTAA's
own activities are the source of the discharge, the discharge will be discontinued. If
the discharge results from a source other than PTAA, such as a PTAA tenant, PTAA
shall take such reasonable actions as it shall determine, within its authority, to assist
in the removal of the discharge. PTAA will also include in all new lease agreements
that it enters into with its tenants a requirement that, upon discovery by the tenant or
the receipt of notification, the tenant will take such remedial actions as may be legally
required with respect to any illegal use or release of hazardous materials by the tenant
on PTAA property.
Identification of Potential Storm Water Retrofit Locations
Regulation:
(f) Identification of suitable locations for potential storm water retrofits (such as riparian
areas) that could be funded by various sources.
Goal:
To develop a process to identify and plan for storm water retrofits in the Randleman
Lake Watershed.
August, 2001 Section 7-Page 7 Randleman Lake
Action Items:
The removal of existing Built Upon Area from Zone 3 and surrounding land, as
described above, will result in the restoration of natural ground cover, including grass and
low shrub-type vegetation. (Tall growing trees will not be permitted within the RPZ in the
approach to Runway 5L). In grading the previously developed land, PTAA will develop a
series of meandering grass swales. A grass swale is noted by the NCDENR in its publication
of Best Management Practices as potentially removing up to 35% of Total Suspended Solids
(TSS). PTAA will also consider planing grass filter strips below any remaining impervious
surface to filter runoff from these areas. Filter strips are noted by the NCDENR as
potentially removing up to 40% of TSS.
August, 2001 Section 7-Page 8 Randleman Lake
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JOB NAME ???' ' TASK Q
"?? (u?GGC
LAW Engineering & Environmental Services, Inc.
3301 Atlantic Avenue
BY
DATE / B
Raleigh, NC 27604

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Piedmont Triad International Airport November 01, 2001
LAW Project 30740-0-4253 Wetland and Stream Mitigation Plan
Table 3b Proposed USACE Wetland and Stream Mitigation Summary
WETLAND PRESERVATION CREATION RESTORATION TOTAL CREDIT
MITIGATION acres ratio credit acres ratio credit acres ratio credit Acres (23.8 needed)
Horsepen Creek 0.0 10.0 0.0 11.0 6.0 1.8 6.0 2.0 3.0 17.0 18% 4.8 20%
0 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
Brush Creek 52.3 5.0 10.5 5.3 6.0 0.9 7.1 2.0 3.6 64.7 69% 14.9 61%
0 5.0 5.0 1.0 0.0 6.0 0.0 0.0 2.0 0.0 5.0 5% 1.0 4%
North Park 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
Robinson Park 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
WillowBrook Par] 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
0 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
Benaja Swamp 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
0 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
Couch Property 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
0 0.0 10.0 0.0 0.0 6.0 0.0 0.0 2.0 0.0 0.0 0% 0.0 0%
Causey Farms 0.0 10.0 0.0 0.0 6.0 0.0 7.0 2.0 3.5 7.0 7% 3.5 14%
SUBTOTAL: 57.3 9.2 11.5 16.3 6.0 2.7 20.1 2.0 10.1 93.7 24.2
61% 47% 17% 11% 21% 41% 3.9 0.5
STREAM PRESERVATION ENH ANCEMENT RESTORATION TOTAL CREDIT
MITIGATION l.f. ratio credit 1.f ratio credit l.f. ratio credit Linear Feet (13917 needed)
Horsepen Creek 0 10.0 0 0 4.0 0 4,960 1.0 4,960 4,960 24% 4,960 36%
0 0 10.0 0 0 4.0 0 0 1.0 0 0 0% 0 0%
Brush Creek 3,690 5.0 738 0 4.0 0 100 1.0 100 3,790 18% 838 6%
0 2,000 5.0 400 0 4.0 0 0 1.0 0 2,000 10% 400 3%
North Park 0 10.0 0 0 4.0 0 650 1.0 650 650 3% 650 5%
Robinson Park 0 10.0 0 0 4.0 0 950 1.0 950 950 5% 950 7%
WillowBrook Parl 0 10.0 0 0 4.0 0 910 1.0 910 910 4% 910 7%
0 0 10.0 0 0 4.0 0 0 1.0 0 0 0% 0 0%
Benaja Swamp 0 10.0 0 0 4.0 0 0 1.0 0 0 0% 0 0%
0 0 10.0 0 0 4.0 0 0 1.0 0 0 0% 0 0%
Couch Property 0 10.0 0 800 5.0 160 0 1.0 0 800 4% 160 1%
0 0 10.0 0 0 4.0 0 0 1.0 0 0 0% 0 0%
Causey Farms 0 10.0 0 2,250 4.0 563 4,500 1.0 4,500 6,750 32% 5,063 36%
SUBTOTAL: 5,690 9.2 1,138 3,050 4.1 723 12,070 1.0 12,070 20,810 13,931
27% 8% 15% 5% 58% 87% 1.5 14
Prepared / Date:
1 of 1 Checked / Date:

AMACTEC
' November 3, 2003
Ms. Jean B. Manuele, Chief
' Raleigh Regulatory Field Office
U.S. Department of the Army
Wilmington District Corps of Engineers
Regulatory Division
' P.O. Box 1890
Wilmington, NC 28402-1890
WETLANDS/ 401 GROUP
NO V 0 4 2003
WATER QUALITY SECTION
Mr. John R. Dorney, Chief
401 Wetlands 'Certification Unit
N.C. Dept. Environment and Natural Resources
Division of Water Quality
1650 Mail Service Center
Raleigh, NC 27699-1650
' Attention: Mr. John Thomas . Ms. Cyndi Karoly
Subject: Proposed Revision to Off-Site Component of Mitigation Plan for
' Piedmont Triad International Airport
Section 404 Action ID No. 200021655
Section 401 Water Quality Certification No. 3428
' Dear Ms. Manuele and Mr. Dorney:
' Pursuant to discussions of October 30, 2003, on behalf of the Piedmont Triad Airport Authority
(PTAA, applicant) we are hereby requesting your concurrence that the three off-site stream
restoration components located in Burlington (2,510 linear feet total), of the Wetland and Stream
' Mitigation Plan for the referenced project, be replaced by an equal linear footage of additional
stream restoration at the Causey Farm site (to total 5,910 linear feet, if approved). It is
anticipated that the contiguous Causey Farm stream restoration project will provide better success
potential and more appropriate functional replacement for stream impacts than the relatively
' short, separate Burlington stream segments constrained by utilities, landfill, park/municipal
ordinances, adjacent landowners, and public use. We respectfully request that the attached
Conceptual Mitigation Report replace the Burlington and previously submitted Causey Farm
t components of the Wetland and Stream Mitigation Plan for this project. Please do not hesitate to
contact me regarding the proposed revisions to the off-site mitigation component.
Sincerely,
MACTEC ENGINEERING AND CONSULTING, INC.
' Richard B. Darling, C.E
Principal Environmen Scientist
' Enclosures: Conceptual Mitigation Report for Causey Farm Mitigation Site
cc: Mickie L. Elmore, PTAA.
Kevin J. Baker, Baker & Associates.
' RBD/KJB/MLE:rbd
P:\30740\2000 Projects\4253 PTTA\MOdification\Request Modification Ldoc
' MACTEC Engineering and Consulting
3301 Atlantic Avenue • Raleigh, NC 27604
' 919-876-0416 • Fax: [phone]
WETLANDS Preservation Creation Restoration Total
Horse en Creek 12.6 acres 2.0 acres 14.6 acres
Brush Creek 69.9 acres 5.3 acres 7.4 acres 82.6 acres
Cause Farms 4.0 acres 4.0 acres
Subtotal: 69.9 acres 17.9 acres 13.4 acres 101.2 acres
STREAMS Preservation Restoration Total
Horse en Creek 6,107 linear feet 6,107 linear feet
Brush Creek 14,510 linear feet 200 14,710 linear feet
Cause Farms 5,910 linear feet 5,910 linear feet
Subtotal: 14,510 linear feet 12,217 linear feet 26,727 linear feet

O
CONCEPTUAL MITIGATION REPORT
CAUSEY FARM MITIGATION SITE
GUILFORD COUNTY, NORTH CAROLINA
Prepared for:
d'+ d
Restoration Systems
1101 Haynes Street, Suite 203
Raleigh, North Carolina 27604
Prepared by:
1
EcoScience
EcoScience Corporation
1101 Haynes Street, Suite 101
Raleigh, North Carolina 27604
February 2002
i
1
1
1

1
1

TABLE OF CONTENTS
Page
LIST OF APPENDICES, FIGURES, AND TABLES ............................ ii
1.0 INTRODUCTION ............................................ 1
2.0 RELEVANT FEATURES ........................................ 5
2.1 Physiography, Topography, and Land Use ...................... 5
2.2 Vegetation ........................................... 8
2.3 Stream Characterization .................................. 8
2.3.1 Stream Classification ............................... 10
2.3.2 Dimension ...................................... 10
2.3.3 Profile ......................................... 12
2.3.4 Plan Form ....................................... 12
2.4 Wetlands ............................................ 13
3.0 CONCEPTUAL MITIGATION PLAN ................................ 15
3.1 Stream Restoration ..................................... 15
3.1.1 Channel Construction on New Location .................. 17
3.1.2 Bank Stabilization and Grade Control Structures ............. 17
3.1.3 Bankfull Bench Construction .......................... 18
3.1.4 Ford Removal and Construction ........................ 18
3.2 Wetland Restoration .................................... 19
3.3 Vegetative Planting ..................................... 19
4.0 MONITORING PLAN ......................................... 21
4.1 Stream Monitoring ...................................... 21
4.2 Stream Success Criteria ................................... 21
4.3 Wetland Monitoring ..................................... 21
4.4 Wetland Success Criteria ................................. 22
4.5 Vegetation Monitoring ................................... 22
4.6 Vegetation Success Criteria ............................... 23
4.7 Contingency .......................................... 23
5.0 DISPENSATION OF THE PROPERTY .............................. 24
6.0 REFERENCES ..............................................25
E
r
i
i
i
LIST OF FIGURES
Figure 1: Site Location ...................... .................... 2
Figure 2: Service Area ....................... ................... 3
Figure 3: Topography ....................... .................. . 6
Figure 4: Land Use ......................... ................... 7
Figure 5: Hydric Soils ....................... ................... 14
Figure 6: Conceptual Mitigation Plan ............. ................... 16
LIST OF TABLES
Table 1: Stream Geometry Attributes ............................... 9
APPENDICES
Appendix A: Stream Gauge Data
Appendix B: On-Site Cross Section Data
t

CONCEPTUAL MITIGATION REPORT
CAUSEY FARM MITIGATION SITE
GUILFORD COUNTY, NORTH CAROLINA

1
1.0 INTRODUCTION
Restoration Systems is currently evaluating stream and wetland restoration potential at a site
located in southeastern Guilford County, approximately 5 miles north of the Town of Liberty
(Figure 1). The Causey Farm Mitigation Site encompasses approximately 288 acres of land
which is currently utilized for livestock grazing and hay production. Streams and wetlands
within the property have been cleared of native forest vegetation and are accessible to
livestock, resulting in local disturbance to stream banks and wetland soil surfaces.
The Site is located in U.S. Geological Service (USGS) Hydrological unit #03030002 of the
Cape Fear River Basin (Figure 2). This portion of the Cape Fear River Basin encompasses
portions of Guilford, Rockingham, Caswell, Alamance, Orange, Chatham, and Durham
Counties. Towns potentially serviced by this mitigation project include Greensboro,
Burlington, Reidsville, and Chapel Hill. The Site is intended to be developed to provide stream
and riverine wetland mitigation credit to various projects in the region.
The purpose of this study is to determine potential restoration alternatives on the Causey
Farm Mitigation Site (hereafter referred to as the "Site"). This study is designed to address
the following objectives:
1) Provide plan views of the Site including land use constraints, topographic
features, wetlands, existing vegetation, or other features that may effect the
restoration project.
2) Classify on-site streams according to fluvial geomorphic attributes measured
within each reach.
3) Develop a preliminary, conceptual plan of potential stream and wetland
mitigation activities.
4) Determine a monitoring strategy including mitigation success criteria.
5) ..Assess potential managers for the Site once mitigation activities are complete.
This document is intended to provide information to agency personnel for discussion of
project parameters, including Site suitability and mitigation options / activities. Potential
restoration alternatives have been presented based primarily upon professional judgement.
1

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Co -pai- ion

SITE LOCATION

CAUSEY FARM MITIGATION SITE Dwn. by:
MAF
Ckdby:
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Date:
FIGURE

- Guilford County, North Carolina FEB 2002
Raleigh, North Carolina Project:
98-029

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If restoration is implemented on the Site, a detailed restoration plan will be prepared that
includes stream geometry measurements and wetland characterization from a reference
(relatively undisturbed) site in the region. Quantitative data collected during the design
planning stage may affect mitigation activities proposed in this preliminary study.
4
1 2_0 RELEVANT FEATURES
2.1 PHYSIOGRAPHY, TOPOGRAPHY, AND LAND USE
The Site is located in the southeastern corner of Guilford County, north of the Town of
Liberty (Figure 1). This portion of the state is underlain by the Carolina Slate Belt geologic
formation within the Piedmont physiographic province of North Carolina. The
hydrophysiographic region is characterized by broad, rolling, interstream divides intermixed
with steeper slopes along well-defined drainage ways (Figure 3). This region is characterized
' by moderately high rainfall with precipitation averaging 41 inches per year (NRCS 1977).
' The Site encompasses reaches of two streams including North Prong Stinking Quarter Creek
and an associated unnamed tributary. Drainage areas for each of the streams are depicted
in Figure 3. Drainage basin size ranges from approximately 5.8 square miles for North Prong
Stinking Quarter Creek to approximately 1.0 square mile for the unnamed tributary at the
respective Site outfall. The unnamed tributary and its adjacent floodplain represent the
primary hydrologic feature of the Site. The unnamed tributary flows in a northerly direction
for approximately 6300 linear feet through the Site prior to its convergence with North Prong
Stinking Quarter Creek near the northern property boundary (Figure 3).
The unnamed tributary is characterized as a second order stream extending through a
relatively narrow, steeply sloped valley (approximately 0.006 rise/run [based on USGS 7.5
minute quadrangles]). As the unnamed tributary descends towards North Prong Stinking
Quarter Creek, the valley widens and flattens to an average slope of approximately 0.0023
rise/run (based on USGS 7.5 minute quadrangles). The unnamed tributary watershed
upstream from the Site is characterized mainly by agricultural land use (livestock, row crops,
and hay production), low density residential development, and an airstrip / hanger complex
associated with the Causey Airport facility. Impervious surfaces appear to account for less
than 10 percent of the upstream land coverage.
On-site land use is characterized by livestock and hay production. A residential structure and
I complex of barns and hay storage structures are located centrally within the Site (Figure 4).
The Site is primarily characterized by open pasture and agricultural fields with isolated
hardwood forest stands. Pasture is heavily grazed by livestock with stocking rates of
approximately 5 animal units per acre. Livestock have access to a majority of the Site. No
exclusionary barriers occur adjacent to on-site streams or wetlands and livestock appear to
have degraded stream banks and wetland soils.

5

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CAUSEY FARMS '
MITIGATION
SITE BOUNDARY

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f'orporation
Raleigh, North Carolina 27605
Client:

Project:
CAUSEY FARMS
MITIGATION
SITE
GUILFORD COUNTY,
NORTH CAROLINA
Title:
TOPOGRAPHY
Dwn By: Date:
MAF FEB2002
NORTH PRONG STINKING
QUARTER CREEK WATERSHED
0 2000 ft. 4000 ft.
1:24.000 _ .'•2?J?. ' (?" _
Source: USGS 7.5 Minute Topo Maps (Climax. Kimesville. N.C.) - - ' 'i
-- ? - -- ate- ?? .-•?..,?? :. . ?_????? « ?. T,T T,,,? ,????,- ,,,_, ,.. ...??.?.. _ . .. .
UNNAMED TRIBUTARY
-? WATERSHED

Ckd By. Scale:
WGL As Shown
ESC Project No. 98-029
FIGURE
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Raleigh, North Carolina 27605
Project:
CAUSEY FARMS
MITIGATION
SITE
GUILFORD COUNTY,
NORTH CAROLINA
Title:
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FOREST
v
TIMBERED LAND
BEAVER IMPOUNDMENT
EXIST. STREAM CHANNELS
PROJECT BOUNDARY
LAND USE
Dwn By. Dale:
MAF FEB 2002
Ckd By: Scale:
WGL As Shown
Esc Project No 98-029
FIGURE
4

' 2.2 VEGETATION
The Site is characterized by pasture land with a few isolated forest stands. The Site is
heavily grazed and / or receives regular vegetative maintenance and does not appear to be
advancing past a secondary seral community. Riparian fringes have little vegetative cover and
are dominated by species such as blackberry (Rubus argutas) and multiflora rose (Rosa
multiflora).
i Isolated patches of both hardwood forest and mixed pine forest occur in the floodplain south
of Smithwood Road which bisects the property from west to east. Livestock have access to
the mixed pine forest while the hardwood forest remains mostly fenced. The remaining
forested communities are narrow strips of trees and shrubs growing along fence lines. The
primary species are eastern red cedar (Juniperus virginiana), persimmon (Diospyros virginiana),
f sweetgum (Liquidambar styraciflua), and Chinese privet (Ligustrum sinense).
' Pasture land dominates the Site and is characterized by native grasses with various invasive
species such as pig weed (Chenopodium album), cocklebur (Xanthium strumarium), and
ragweed (Ambrosia artemisiifolia). Patches of shrubby species occur adjacent to the streams
and tributaries; however, these species have been bush hogged (mowed) or manually cleared.
Shrubby species include blackberry, multiflora rose, black willow (Salix nigra), red maple (Acer
rubrum), and sweetgum. Multiple wetland depressional areas support a wet herbaceous
assemblage dominated by rushes and sedges (Juncus and Carex spp.).

Reforestation of hardwood species may be achievable within the entire on-site floodplain
complex. Forest species are expected to vary from bottomland hardwood forest to a more
mesic levee mixed forest based on topographic variations. Species composition should mimic
reference forest measurements of similar undisturbed floodplains in the region. An ecological
approach to restoration is expected within the Site; therefore, a varied forest structure should
target habitat diversity.
2.3 STREAM CHARACTERIZATION
On-site streams have been characterization based on fluvial geomorphic principles (Rosgen
1996). Table 1 provides a summary of measured stream geometry attributes under existing
conditions (considered to be unstable) and a preliminary estimate of potentially stable stream
attributes. Establishment of specific design channel attributes will require measurement of
a reference (relatively undisturbed and stable) stream reach within the hydrophysiographic
region. Preliminary estimates of stable stream attributes are based primarily upon data
observations along the existing reaches, regional curves (Harman et. al. 1999), and stream
gauge data collected in stream gauges in the vicinity of the Site.
8

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BEAVER IMPOUNDMENT
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PROJECT BOUNDARY
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' 2.3.1 Stream Classification
Stream geometry and substrate data have been evaluated to orient stream restoration based
on a classification, utilizing fluvial geomorphic principles (Rosgen 1996). This classification
m
classes associated with the Site include E, C, and G. Each stream type is modified by a
' number from one through six (example: C5) denoting a stream type which indicates a
substrate dominated by 1) bedrock, 2) boulders; 3) cobble, 4) gravel, 5) sand, or 6) silt/clay.
stratifies width/depth streams ratio, into sinuosity, comparable channel groups slope, based and on stream pattern, substrate dimension, profile, composition and substrate
characteristics. Primary components of the classification include degree of . Strea entrenchment,
Historically, on-site reaches may have been characterized as E4-type streams. E-type streams
are characterized as slightly entrenched, riffle-pool channels exhibiting high sinuosity (> 1.5).
In North Carolina, E-type streams often occur in narrow to wide valleys with well- developed
alluvial floodplains (Valley Type VIII). E-type streams typically exhibit a sequence of riffles
and pools associated with a sinuous flow pattern. E-type channels are typically considered
stable. However, these streams are sensitive to disturbance and may rapidly convert to other
stream types.
Clearing of riparian vegetation, ditching and straightening activities, and hoof shear from
livestock entering the channels, have resulted in bank collapse and erosion of on-site reaches.
A majority of the on-site reaches are currently characterized as unstable, E/C- and E/G -type
channels which are systematically entrenching (G-type) and widening (F-type) due primarily
to the lack of deep rooted riparian vegetation. Bank materials are expected to continue to
erode until a stable floodplain has been scoured at the current elevation of the disturbed
streams.
A majority of the unnamed tributary reach appears to have been dredged, straightened, and
impacted by land clearing and livestock grazing. Grazing of livestock near stable streams (E
stream-type) typically leads to channel adjustments including increases in bank erosion,
width/depth ratio, stream gradient, and sediment supply. In addition, these impacts may lead
to decreases in channel sinuosity, meander width ratio, and sediment transport capacity
(Rosgen 1996). Straightening of channels induces erosion of bed and bank materials, which
exasperates sediment transport problems. The unnamed tributary is expected to continue to
erode and deposit sediment into receiving streams until a stable stream pattern has been
_ carved from. the adjacent floodplain.
2.3.2 Dimension
' Regional curves (Harman et. a/. 1999) and field indicators of bankfull were utilized to
determine bankfull channel cross-sectional area in on-site reaches. The cross-sectional areas
10

' were then utilized to determine the bankfull width, average bankfull depth, maximum depth,
and floodprone area of existing on-site channels. Using this method, a departure from
stability could be estimated based on a comparison of existing and proposed (stable)
dimension variables.
Based on preliminary information, regional curves appear to overestimate the stable channel
cross-sectional area at the Site. The existing North Prong Stinking Quarter Creek is
characterized by a downstream cross-sectional area of approximately 38 square feet. This
reach of the creek is classified as an E-type channel with a bank-height-ratio of 1.0. The
channel does not exhibit excessive bank collapse and appears relatively stable. Regional
curves indicate that a cross-sectional area of greater than 70 square feet is expected to occur
in this reach.
' Regional curve comparisons to on-site cross-sectional data prompted a search of nearby
stream gauges to verify the accuracy of regional curve predictions of bankfull discharge at
the gauged site. Three gauged streams were identified which appear to represent similar
drainage basin characteristics to the Site (Reedy Fork near Oak' Ridge, Rocky River at SR
' 1300, and Cane Creek Near Orange Grove). A peak annual discharge with a return interval
of 1 .3 years has been utilized to predict bankfull discharge for this study.
' Regional curves predicted a 1.7 year return interval at two of the three gauges, indicating that
regional curves may slightly overestimate bankfull discharge and bankfull cross-sectional area
' at the Site (gauge data is included in Appendix A). This information suggests that
measurement of a nearby reference (relatively undisturbed) reach is imperative for the
development of dimension variables to be constructed at the Site. However, for the purposes
of this preliminary study, the regional curves have been utilized to predict stable channel
dimension variables (Table 1).
Based on regional curve estimations of cross-sectional area, it appears that various stream
bank erosional scenarios occur on-site. The majority of the Site is characterized by channel
incision which results in bank-height-ratios ranging from 1.0 to 1.5 (low bank height / bankfull
height). The down-cut may have resulted from a lack of adjacent deep-rooted riparian
vegetation. The down-cut has resulted in an incised channel that has begun to actively erode
channel banks below the effective rooting depth of existing riparian vegetation.
These channels are expected to widen, causing the stream type to migrate towards an F-type
(widened gully) or disturbed C-type stream. However, until an active floodplain has been
' carved, the channel is expected to remain an unstable, narrow and deep, E/G-type channel.
11

' Based on this assessment, measures designed to reduce the bank height ratio and widen the
active floodplain are recommended along the channel.
2.3.3 Profile
Based on USGS quadrangles, the on-site valley slope measures approximately 0.0023 rise
r / run for North Prong Stinking Quarter Creek and 0.006 rise / run for the unnamed tributary.
Estimated valley slopes appear typical for the Piedmont physiographic region of North Carlina.
Water surface slopes were estimated by dividing the valley slope by channel sinuosity.
Sinuosity was inferred from aerial photography and /or Global Positioning System technology.
Sinuosity for North Prong Stinking Quarter Creek and its unnamed tributary were measured
at 1.3 and 1.1, respectively. Calculated water surface slopes (Tables 1), range from
approximately 0.0018 rise/run for North Prong Stinking Quarter Creek and 0.0055 rise / run
for the unnamed tributary.
Dredging and straightening of the unnamed tributary appears to have resulted in an over
steepened water surface profile. Currently the water surface profile is approximately equal
to the valley surface slope; 0.0055 versus 0.006 (Table 1). In addition, channel
modifications have obliterated the riffle-pool morphology characteristics of stable streams in
the region. Existing riffle slopes and pool slopes are, on average, outside the range of
acceptable values considered for E-type streams in the region.
An over steepened water surface slope may be detrimental to on-site channels due to
increased erosive forces, altered secondary flow cells, and energy dissipation, possibly
resulting in a step-pool channel morphology. Measures designed to reduce water surface
slope and restore riffle-and pool-slopes to suitable ranges is expected to be targeted
throughout the unnamed tributary.
' 2.3.4 Plan Form
Aerial photography and in-field surveys were utilized to determine existing on-site plan form
variables. Once the existing plan form variables were identified, they were compared to ratios
' of stable plan form variables based on fluvial geomorphic methods (Rosgen 1996). Using this
method, a departure from stability could then be estimated.
On-site channels support sinuosities ranging from between 1.1 to 1.3 (thalweg distance /
valley distance). The unnamed tributary sinuosity (1.1) is considered low (based on
' geomorphic priciples) and North Prong Stinking Quarter Creek is considered moderate (1 .3).
Stable sinuosities for E-type streams are expected to measure approximately 1.5. Reduced
sinuosities may result from bank collapse, channel obliteration, and dredging and straightening
of channels. The unnamed tributary exhibits a belt width that ranges from 38 to 112 feet

12

which is well below the expected range of 134 to 268 feet. The North Prong Stinking
Quarter Creek belt width ranges from 228 to 342 feet and appears to represent stable pattern
characteristics (based on regional curve estimates and reference ratios). On-site meander
wavelengths average approximately 114 feet on the North Prong Stinking Quarter Creek but
no distinct, repetitive pattern of sinuous riffle and / or pools were identifiable in the unnamed
tributary due to straightening activities. A stable maximum wavelength for the unnamed
tributary is expected to range between 94 to 160 feet with pool-to-pool spacings of
approximately 54 to 80 feet (Table 1).
Based on plan form variables, on-site channels include reaches that have been dredged and
' straightened or have been degraded by bank collapse and channel obliteration, thereby
reducing the beltwidth, meander length, and sinuosity of the reach. Mitigation efforts
' targeting increases in sinuosity, beltwidth, and meander wavelength will be investigated along
degraded sections to establish parameters within the range of potentially stable values for
these attributes.
2.4 WETLANDS
Jurisdictional wetlands are defined by the presence of three criteria: hydrophytic vegetation,
hydric soils, and evidence of wetland hydrology during the growing season (DOA 1987).
Portions of the Site historically supporting jurisdictional wetlands may have been characterized
by palustrine, forested wetlands and groundwater seeps which were seasonally flooded.
These wetland areas have been impacted by ditching, capping of spring heads, livestock
' trampling, deforestation, and groundwater draw-down from stream channel downcutting.
Currently, on-site wetlands are characterized by a monoculture of sedges and rushes which
' are subjected to livestock trampling and heavy grazing pressure. Jurisdictional wetlands are
underlain by alluvial soils of the Wehadkee series which occur in a large patch-like network
' throughout the on-site floodplains (Figure 5). Significant areas of jurisdictional wetlands
occur adjacent to both the unnamed tributary and North Prong Stinking Quarter Creek.

I

Based on aerial photography and on-site investigations, approximately 21 acres of the
floodplain currently are underlain by hydric soils that may have at one time supported
jurisdictional wetlands. Down-cutting of stream channels and ditching of spring heads may
have effectively lowered the adjacent groundwater table and soil saturation to below
jurisdictional thresholds. In addition, livestock trampling and regular maintenance of
agricultural fields have disturbed the natural state of these sensitive areas. Removal of
livestock and planting with native forested vegetation may allow the floodplain to preform
wetland functions such as flood-flow suppression, nutrient cycling, pollutant removal, and
provide habitat for native species.
13

r
r
r
r
r
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F
TABLE 1
STREAM GEOMETRY ATTRIBUTES
CAUSEY FARM MITIGATION SITE

Wbkfl
D.,

lt
Wb

Wrpa
BHR
Wbkfl/ eve Abkfl

(riffle) Aexist
(riffle)
SWB
(rise/run)
Salley
(rise/run)
Sin
Substrate
Stream Type
Reach (Mies
} (riffle) (riffle) e
(ft) (ft) (ft) (ft) bank height ratio Mdth•depthratio (ft2) (ft2)
(ft) (ft)

Existing Stream Attributes, North Prong Stinking Quarter Creek, Piedmont Physiographic Province
55 0018 ,0023 1.3
1
0 66,1 .
3
23 4
2 278 323 114 57.4 .
Average . . F

9
6-32
13

9-2.8
1

228-342

277-369

76186

38-93 -- -7 61,9 70,3 38 72 ------- --°°. Sand and

Silt
E/C
Range 5.8 .
. . .____
._ Average X1S„,° 1.3 --- ---
-°°""
------•
13
15.2
5.4
2.7
------
Average XIW?fl -------
7
8 4
L8-4
-------
Range X1S„,°
'•""'-"
11-16 13-17.3 .
3.6- .
Range X/W
fl
bk
Stable Attributes based on Regional Curves
0023
3
1
26 5
2 278 323 260 130 1,0
g
66.1
-------
.0018
.
,
Average .

------

28 342

77 369

82 312

04 156

-------
8-10
61.9-70.3
-----
""""-" -------
•------
Sand and

Gravel
E
Range
Range
5,8 ------ Average X/S„,°
4
12 10 5 ------- -
Average X/Wbkfl ------- ------- 11 . __.
__..
6 ------- ------- Range X/S„,° -_•.•.-
2
7.13
8 10.6 14.1 7-12 4-
Range XlWEkfl .
.

A
Wbkfl

BVg
D

Wb
lt

Wfia

Lm

LP•P

BHR

b/t)x„e Abkfl

(riffles Aexlet

(riffle)

L

Swe

rise/run) S?euey

)

(rise/ru

in

ubstrate

tream Type
Reach `h
?
(mi i riffle)
( le)
(ri ff e
(ft) (ft) (ft) (ft) bank height ratio width•depth ratio (ft2)
(ft2)
(fits (ft) 7?

Existing Stream Attributes, Unnamed Tributary, Piedmont Physiographic Province

1
1
F
1
2 8 20.9 40 .0055 .006 .
A 12 1
5 42 99 .
verage . No distinct, repetitive

1
6-15
7

3-1
7
1

38 112

80 117 pattern of riffles and 1.0.1.5 5-12 20-21.4 12.8-88 ------ ---•--- •°---- Sand and

Silt
E E1G
Range .
. .
. pools due to ditching 1
1 -•-•
1.0 Average XIS„„ .
------- 3
5 8.3 and straightening ------
Average X/Wbkfl --•---- . activities
Range X/S,,°
Range XlWbkfl ------'
------
3.2-9.3
6.7-10

Stable Attributes based on Regional Curves
1
5
009 ,006 .
Average 13.4 1.6 200 99 134 67 1.0 9
20.9
-------
.
••-•--- -----•- Sand and
Range 13.1-13,6 1,5-1.6 134-268 80-117 94-160 54-80 -------
8.10
20-21.4
--- _ _
•-""•"

Gravel
E
1.0

10

5 -------
Average X1S„,°
1,5
-•- --
Average X/Wbkfl ______' __."___
15
7.4
, 2 4-6 ------
-------
Range XIS,,
10 20 6-8.7 7-1
Range X/Wbkn

11

3_0 CONCEPTUAL MITIGATION PLAN
The primary goals of this mitigation plan include: 1.) construction of a stable, riffle-pool stream
channel; 2) enhancement of the water quality functions in the on-site, upstream, and
downstream segments of North Prong Stinking Quarter Creek and its associated unnamed
tributaries; 3) creation of a natural vegetation buffer along on-site stream channels; 4)
restoration of wildlife habitat associated with a riparian corridor / stable stream; and 5)
restoration of jurisdictional wetland hydrology to the floodplain of North Prong Stinking
Quarter Creek and the unnamed tributary.
Primary activities designed to restore the stream and wetland complex include: 1) stream
restoration; 2) stream enhancement; 3) wetland restoration; and 4) vegetative community
restoration (Figure 6). The mitigation concept outlined in Figure 6 is expected to restore
approximately 6840 linear feet of stream and 5 to 7 acres of jurisdictional wetland, along
with the subsequent enhancement of 3180 linear feet of stream and 14 to 16 acres of
jurisdictional wetland.
3.1 STREAM RESTORATION
Alternatives for stream restoration are designed to provide a stable stream channel and in-
stream aquatic habitat while protecting the adjacent stream banks from extensive erosion.
The alternatives proposed for this project are based primarily on professional judgement and
potentially stable stream attributes characteristic of the region.
' The majority of the on-site stream channels are classified as E/G stream types. The cross-
sectional area of on-site channels appear to have become unstable due to excessive bank
' erosion from deforestation, livestock trampling, and channel dredging / straightening. In
addition, the bank height ratio of on-site channels, especially in the unnamed tributary,
appears to have been elevated from 1.0 (stable stream channel) to between 1.0 and 1.5.
' Bank collapse, channel straightening, and erosion also appears to have reduced sinuosity of
on-site channels to below the modal concept for stable E-type (highly sinuous) and C-type
(moderately sinuous) streams in the region.
Stream mitigation options should focus on the reduction of channel cross-sectional area
(decreasing bank-height-ratio) and increasing sinuosity (reducing water surface slope). Stream
mitigation activities which may be utilized to achieve these results include: 1) the construction
of a channel on new location throughout most of the unnamed tributary; 2) bank stabilization
and installation of grade control structures within secondary tributaries and North Prong
Stinking Quarter Creek; and 3) the construction of bankfull benches near the upstream and
' downstream terminus of the Site. These mitigation activities are expected to result in
? 15

VEGETATIVE PLANTING AREAS
BEAVER IMPOUNDMENT
acres
45
EcoScience
Corporation
Raleigh, North Carolina 27605
Client:

Project
CAUSEYFARMS
MITIGATION
SITE
GUILFORD COUNTY,
NORTH CAROLINA
Title:
CONCEPTUAL
MITIGATION
PLAN
own By. Date:
MAF FEB2002
Ckd By: Scale:
WGL As Shown
ESC Project No.: 98-029
FIGURE
6

approximately 6840 linear feet of stream restoration and 3180 linear feet of stream
enhancement (Figure 6).
' 3.1.1 Channel Construction on New Location
Channel construction on new location is expected to occur predominantly in the unnamed
tributary due to limited concerns of hydrologic trespass. Channel construction is expected
to entail the preparation of a belt width corridor prior to channel excavation. Belt width
' corridor preparation will entail channel staking and any necessary grading prior to channel
excavation. Spoil material excavated during the grading and channel excavation process is
expected to be stockpiled adjacent to the existing unnamed tributary channel that will be
' abandoned and then backfilled.
t Once belt width corridor preparation is complete, the proposed channel will be excavated to
the average width, depth, and cross-sectional area derived from reference reach studies and
detailed measurements of on-site streams. The stream banks and local belt width area of
' constructed channels will be immediately planted with shrub and herbaceous vegetation.
Black willow shrubs may be removed from the banks of the abandoned channel and
stockpiled during clearing to be replanted in the new stream channel. Root mats may also
be selectively removed from adjacent areas and placed as erosion control features on channel
' banks.
Particular attention will be directed toward providing vegetative cover and root growth along
' the outer bends of each stream meander. Available root mats or biodegradable, erosion
control matting may be embedded into the break-in-slope to promote more rapid development
' of an overhanging bank. Willow stakes will be collected on-site and inserted through the root
/ erosion mat into the underlying soil. The reconstructed channel and vegetation will be
allowed to stabilize for a minimum of four months during the growing season prior to
' diversion of flow. Flow will be diverted incrementally to allow for adaption within the
reconstructed channel.
' 3.1.2 Bank Stabilization and the Installation of Grade Control Structures
Bank stabilization may be performed along eroding outer bends within existing channel
' reaches of North Prong Stinking Quarter Creek, the hardwood forest section of the unnamed
tributary, and two secondary tributaries entering the unnamed tributary from the east (Figure
6). Particular attention should be placed on outer bends of eroding pools or excessively
' eroding banks. Bank slopes will be protected through placement of appropriate structures
such as brush mattresses, live brush layering, matting, rock toe protection, root wads, cross-
vanes, and / or J-Hook vanes.
17

Grade control structures may be placed in the channel to elevate local water surface profiles
in the channel, potentially flattening the water energy slope or gradient. The structures would
' likely consist of boulder-size rock vanes or step-pool devices designed primarily to direct
stream energy into the center of the channel and away from actively eroding banks. In
addition, the structures would be placed in relatively straight reaches to provide secondary
r (perpendicular) flow cells during bankfull events.
' 3.1.3 Bankfull Bench Construction
The potential excavation of a bankfull floodplain bench in North Prong Stinking Quarter Creek
is expected to: 1) remove the eroding material and collapsing banks; 2) promote overbank
flooding during bankfull flood events; 3) reduce the erosive potential of flood waters; and 4)
increase the width of the active floodplain. After excavation, the bench would provide a
' relatively level floodplain surface which could be stabilized with suitable erosion control
measures. Planting of the bench with native floodplain vegetation may reduce erosion of
bench sediments, reduce flow velocities in flood waters, filter pollutants, and provide wildlife
' habitat.
' Floodplain benches may be constructed in North Prong Stinking Quarter Creek and reaches
where hydrologic trespass may preclude increased water surface elevation. Stream reaches
that may receive floodplain bankfull benches are located at the upper extent of on-site
' streams, near property boundaries, and at the Site outfall.
' 3.1.4 Ford Removal and Construction
Several on-site fords have been identified in both the unnamed tributary and North Prong
Stinking Quarter Creek. These existing fords have resulted in impoundment of on-site
' streams and obliteration of stream banks; therefore, removal of the fords is proposed within
the Site. Replacement fords may be constructed to allow the passage of cattle and or
' vehicles. The fords are expected to consist of a shallow depression in the stream banks
where vehicular crossings can be made. Flexibility in the location of the fords exists and may
be changed upon request by landowners or on-site construction managers. The fords shall
' be constructed of hydraulically stable rip-rap or suitable rock and should be large enough to
handle the weight of anticipated vehicular traffic. Approach grades to the fords should be
' approximately 30 feet in length and constructed of hard, weather-resistant crushed rock or
other permeable material which is free of fines. The bed elevation should be equal to the bed
elevation of the design stream channel above and below the fords to reduce the risk of
headcutting.
18
t
' 3.2 WETLAND RESTORATION
Alternatives for wetland restoration are designed to restore a fully functioning wetland system
' which will provide surface water storage, nutrient cycling, removal of imported elements and
compounds, and will create a variety and abundance of wildlife habitat. Wetland restoration
alternatives are based primarily on professional judgement and a reference wetland is
r expected to be measured to determine vegetative features, micro- and macro- topographic
variations, and soil structure components to be targeted during development of the Site.
' Portions of the Site underlain by hydric soil have been impacted by ditching of natural springs,
channel incision, vegetative clearing, livestock grazing, and earth movement associated with
' agricultural practices. These areas are characterized by a near mono-culture community of
sedges, grasses, and rushes, under severe impact from soil compaction by livestock
' trampling. Wetland mitigation options should focus on the restoration of vegetative
communities, elevating groundwater tables to jurisdictional conditions, and the re-
establishment of soil structure and micro-topographic variations within the existing floodplain.
Restoration of wetland hydrology and wetland soil attributes may' involve: 1) excavation and
' grading of elevated spoil and sediment embankments; 2) placement of impervious channel
plugs along abandoned reaches; 3) backfilling of entrenched stream reaches; and 4)
scarification of pasture soils prior to planting. In addition, the construction of (or provisions
' for) surface water storage depressions (ephemeral pools) also adds an important component
of groundwater restoration activities. These mitigation activities are expected to result in the
' restoration of approximately 5 to 7 acres and enhancement of approximately 14 to 16 acres
of jurisdictional wetland at the Site.
3.3 VEGETATIVE PLANTING
Deep-rooted, riparian vegetation will be restored within the entire floodplain complex of both
' the unnamed tributary and North Prong Stinking Quarter Creek. Planting vegetation on
cleared stream banks is proposed to re-establish vegetation community patterns within the
stream corridor, associated side slopes, and transition areas. Vegetating the floodplain and
' stream banks is expected to provide stream bank stability, shade and cool surface waters,
filter pollutants from adjacent runoff, and provide habitat for area wildlife. The vegetated
' stream buffer will extend to a minimum of 50 feet on both sides of the stream. Scarification
of floodplain surfaces will be required prior to vegetation planting.
' Variations in vegetative planting may occur based on topographic locations and hydraulic
conditions of the soil. Vegetative species composition should mimic reference forest data and
' on-site observations. Species expected for this project may include the following elements.
19

Shrubs I Trees
1. Green Ash (Fraxinus pennsylvanica.)
2. Northern Red Oak (Quercus rubra)
3. American Sycamore (Platanus occidentalis)
4.
5. American Elm (Ulmus americana)
Ironwood (Carpinus caroliniana)
6. Black Cherry (Prunus serotina)
7. Smooth Black Haw (Virburnum prunifolium)
8. Black Gum (Nyssa Sylvatica)
Stream-Side Assemblage
1 . Black Willow (Salix nigra)
2. Box Elder (Acer negundo)
3. Ironwood (Carpinus caroliniana)
' 4.
5 River Birch (Betula nigra)
American Sycamore (Platanus occidentalis)
.
' Stream-Side Shrub Assemblage
1. Tag Alder (Alnus serrulata)

' 2.
3. Buttonbush (Cephalanthus occidentalis)
Elderberry (Sambucus canadensis)
4. Arrow-wood Viburnum (Viburnum dentatum)
' 5. Possumhaw Viburnum (Viburnum nudum)
6. Bankers Dwarf Willow (Salix cotteli)
' 7. Black Willow (Salix nigra)
Approximately 45 acres of on-site floodplain is expected to be re-vegetated during mitigation
' construction. Species distribution and densities are expected to be determined during the
detailed mitig ation planning phase of the project.

1 20

1-1
r 4_0 MONITORING PLAN
Monitoring of Site restoration efforts is expected. to be performed until success criteria are
' fulfilled. A monitoring plan and detailed success criteria are expected to be developed during
the detailed mitigation planning phase of the project. However, some guidelines which may
be utilized to develop a monitoring strategy and success criteria follow.
r
4.1 STREAM MONITORING
Annual fall monitoring may include development of a channel plan view, channel cross-
sections on riffles and pools, pebble counts, and a water surface profile of the channel. The
data may be presented in graphic and tabular format. Data to be presented is expected to
include: 1) cross-sectional area; 2) bankfull width; 3) average depth; 4) maximum depth; 5)
width / depth ratio; 6) meander wavelength; 7) belt width; 8) water surface slope; 9)
sinuosity; and 10) stream substrate composition. The streams should subsequently be
classified according to stream geometry and substrate (Rosgen 1996). Significant changes
in channel morphology are expected to be tracked and reported by comparing data in each
' successive monitoring year.
' 4.2 STREAM SUCCESS CRITERIA
Success criteria for stream restoration may include: 1) successful classification of the reach
as a functioning stream system (Rosgen 1996); 2) channel stability indicative of a stable
stream system; and 3) development of diagnostic biological communities over time.
t The channel configuration may be measured on an annual basis to track changes in channel
geometry, profile, or substrate. These data are expected to be utilized to determine the
success in restoring stream channel stability. Specifically, the width / depth ratio should
' remain at or below a value of 14 in each monitoring year. In addition the channel should not
become incised relative to the adjacent floodplain. Modifications to the channel should be
performed to increase or, decrease the sediment transport capacity, or other unstable
attributes, as needed. If the stream channel is down-cutting or the channel width is enlarging
due to bank erosion, additional bank or slope stabilization methods may be employed.
4.3 WETLAND MONITORING
Groundwater gauges are expected to be installed in accordance with specifications in U.S.
Corps of Engineers', Installing Monitoring Wells/Piezometers in Wetlands (WRP Technical Note
HY-IA-3.1, August 1993). Monitoring gauges should be set to a predetermined depth of
' approximately 40 inches below the soil surface in order to obtain a more accurate depiction
of watertable fluctuations. Hydrological sampling may be performed on-site and within
' reference areas throughout the year to compare pre- and post-construction conditions.

21

r 4.4 WETLAND SUCCESS CRITERIA
Target hydrological characteristics may include a minimum regulatory wetland hydrology
criteria based upon reference groundwater modeling. Evaluation of success criteria is
expected to be supplemented by groundwater gauge data and comparison between
restoration and reference areas.
Target hydrological characteristics during years with average rainfall include saturation or
' inundation (free water) within one foot of the soil surface for at least 12.5 percent of the
growing season. Upper landscape reaches and hummocks within wetland areas may exhibit
surface saturation / inundation between 5 percent and 12.5 percent of the growing season.
These 5 to 12.5 percent areas are expected to support hydrophytic vegetation within hydric
soils. If wetland parameters are marginal as indicated by vegetation and hydrology
monitoring, consultation with U.S. Army Corps of Engineers (COE) personnel will be
undertaken to determine jurisdictional extent in these areas.

e

4.5 VEGETATION MONITORING
Restoration monitoring procedures for vegetation are expected to'be designed in accordance
with U.S. Environmental Protection Agency (EPA) guidelines enumerated in (EPA 1990) and
(DOA 1994). A general discussion of the restoration monitoring program is provided.
After planting has been completed in winter or early spring, an initial evaluation may be
performed to verify planting methods and to determine initial species composition and
density. Supplemental planting and additional site modifications are expected to be
implemented, if necessary.
During the first year, vegetation should receive cursory, visual evaluation on a periodic basis
to ascertain the degree of overtopping of planted elements by nuisance species.
Subsequently, quantitative sampling of vegetation should be performed between September
1 and October 30 after each growing season until the vegetation success criterion is
achieved.
During quantitative vegetation sampling in early fall of the first year, sample plots may be
randomly placed within the Site. In each sample plot, vegetation parameters to be monitored
may include species composition and species density. Visual observations of the percent
cover of shrub and herbaceous species are expected to be recorded.
22

' 4.6 VEGETATION SUCCESS CRITERIA
Success criteria have been established to verify. that the vegetation component supports
community elements necessary for floodplain forest development. Success criteria may be
dependent upon the density and growth of characteristic forest species.
Guidelines including survivorship of approximately 320 stems per acre in the first three
monitoring years may be utilized. Subsequently, 290 character tree species per acre may be
surviving in year 4, and 260 tree species per acre in year 5. Planted species should represent
a minimum of 30 percent of the required stem per acre total (96 stems/acre). Each naturally
recruited character species may represent up to 10 percent of the required stem per acre
t total. In essence, seven naturally recruited character species may represent a maximum of
70 percent of the required stem / acre total. Additional stems of naturally recruited species
' above the 10 percent - 70 percent thresholds are discarded from the statistical analysis.
If vegetation success criteria are not achieved based on average density calculations from.
combined plots over the entire restoration area, supplemental planting may be performed with
tree species approved by regulatory agencies. Supplemental planting may be performed as
, needed until achievement of vegetation success criteria.
No quantitative sampling requirements are proposed for herb assemblages as part of the
vegetation success criteria. Development of floodplain forests over several decades are
expected to dictate the success in migration and establishment of desired understory and
groundcover populations. Visual estimates of the, percent cover of herbaceous species and
photographic evidence may be reported for information purposes.

4.7 CONTINGENCY
In the event that vegetation, hydrology, and / or stream success criteria are not fulfilled, a
mechanism for contingency may be implemented. For vegetation contingency, replanting and
extended monitoring periods will be implemented if community restoration does not fulfill
minimum species density and distribution requirements.
Stream reconstruction failure may occur due to increased sediment and discharge during
development within the upper watershed. Stream contingency will likely include identification
and modification of upstream sediment sources, additional stabilization of stream banks, and
re-establishment of stream substrates required to support target aquatic communities.
Recommendations for stream contingency will also be solicited, implemented, and monitored
until the Stream Success Criteria are achieved.
23

Wetland hydrology failure may occur due to insufficient hydrologic flow and or unpredictable
hydraulic conductivities of disturbed soils. Wetland contingency may likely include
modifications of floodplain and or subsurface soils required to support target hydrologic
regimes.
r Recommendations for vegetation, stream, and wetland contingency is expected to be
solicited, implemented, and monitored until the Success Criteria are achieved.
5.0 DISPENSATION OF PROPERTY
Restoration Systems will maintain the conservation easement within the Site until all
mitigation activities are completed and the mitigation site has been deemed successful. Once
the Site has been developed, the easement may be deeded to a land trust organization or
community entity suitable to the regulatory agencies. A likely candidate for perpetual
maintenance of the easement is Guilford County. The Site may be incorporated into the
Guilford County Division Parks and Recreation for use in environmental education and / or
open space.
The current landowner (Mr. Trager) is expected to retain ownership of the properties. The
conservation easement is expected to be transferred perpetually with the properties upon sale
or development of the property. Covenants and / or restrictions on the deed will be included
t that will ensure adequate management and protection of the Site in perpetuity.

1 24

6.0 REFERENCES
Department of the Army (DOA). 1987. Corps of Engineers Wetlands Delineation Manual.
Tech. Rpt. Y-87-1, Waterways Experiment Station, COE, Vicksburg, MS.
Department of the Army (DOA). 1994. Corps of Engineers Wilmington District.
Compensatory Hardwood Mitigation Guidelines (12/8/93).
Environmental Protection Agency (EPA). 1990. Mitigation Site Type Classification (MIST).
EPA Workshop, August 13-15, 1989. EPA Region IV and Hardwood Research
Cooperative, NCSU, Raleigh, North Carolina.
' Harman, W.A., G.D. Jennings, J.M. Patterson, D.R. Clinton, L.A. O'Hara, A. Jessup, R.
Everhart. 1999. Bankfull Hydraulic Geometry Relationships for North Carolina
Streams. N.C. State University, Raleigh, North Carolina.
Natural Resource Conservation Service (NRCS). 1977. Soil Survey of Guilford County, North
Carolina. U.S. Department of Agriculture.
Rosgen, D. 1996. Applied River Morphology. Wildland Hydrology (Publisher). Pagosa
Springs, Colorado.
Rosgen, D. 1996b. "Classification of Natural Rivers: Reply to the comments by J.R. Miller
and J.B. Ritter." Catena. 27:301-307

25

r

I

1
APPENDIX A
STREAM GAUGE DATA

t
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Peak Streamflow
Reedy Fork Near Oak Ridge, NC
USGS Station #02093800
Drainage Area 20.6 square miles
Return
Water Discharge Exceedance Exceedance Interval
Year (cfs) Probability Probability % (years)
1 1960 3950 0.02 2 46.0
2 1972 2990 0.04 4 23.0
3 1979 2880 0.07 7 15.3
4 1978 2350 0.09 9 11.5
5 1996 2330 0.11 11 9.2
6 1984 2090 0.13 13 7.7
7 2000 2050 0.15 15 6.6
8 1997 1880 0.17 - 17 5.8
9 1993 1590 0.20 20 5.1
10 1969 1500 0.22 22 4.6
11 1959 1460 0.24 24 4.2
12 1991 1440 0.26 26 3.8
13 1989 1310 0.28 28 3.5
14 1973 1250 0.30 30 3.3
15 1987 1250 0.33 33 3.1
16 1965 1210 0.35 35 2.9
17 1977 1210 0.37 37 2.7
18 1975 1040 0.39 39 2.6
19 ' 1982 995 0.41 41 2.4
20 1986 965 0.43 43 2.3
21 1963 960 0.46 46 2.2
22 1974 957 0.48 48 2.1
23 1990 952 0.50 50 2.0
24 1992 864 0.52 52 1.9
25 1970 858 0.54 54 1.8
26 1994 837 0.57 57 1.8
28 1962 . 756 0.61 61 1.6
29 1958 746 0.63 63 1.6
30 1998 741 0.65 65 1.5
31 1971 729 0.67 67 1.5
32 1957 719 0.70 70 1.4
33 1980 670 .,0.72 72 1.4
34 1966 664 0.74 74 1.4
35 1983 664 0.76 76. 1.3
37 1995 582 0.80 80 1.2
38 1981 517 0.83 83 1.2
39 1999 412 0.85 85 1.2
40 1961 408 0.87 87 1.2
41 1964 388 0.89 89 1.1
42 1976 379 0.91 91 1.1
43 9985 378 0.93 93 1.1
44 1988 148 0.96 96 1.0
45 1967 147 0.98 98 1.0

J am F Ltt cz PLed 4, GA C 0-

I-
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I

Peak Streamflow
Cane Creek Near Orange Grove, NC
USGS Station #02096846
Drainage Area 7.5 square miles
Return
Water Discharge Exceedance Exceedance Interval
Year (cfs) Probability Probability % (years)
1 1996 2060 0.08 8 13.0
2 1993 1740 0.15 15 6.5
3 1995 1280 0.23 23 4.3
4 1998 1110 0.31 31 3.3
5 2000 903 0.38 38 2.6
6 1989 864 0.46 46 2.2
7 1994 725 0.54 54 1.9
8 1999 689 0.62 62 1.6
9 1991 516 0.69 69 1.4
10 1997 458 0.77 77 1.3
TT 1992 433 0.85 85 1.2
12 1990 421 0.92 92 1.1

ab a< k

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I

Peak Streamflow
Rocky River at SR1300 Near Crutchfield Crossroads, NC
USGS Station #0210166029
Drainage Area 7.4 square miles
Return
Water Discharge Exceedance Exceedance Interval
Year (cfs) Probability Probability % (years)
1 1998 864 0.08 8 12.0
2 1995 698 0.17 17 6.0
3 1997 673 0.25 25 4.0
4 1991 469 0.33 33 3.0
5 1994 429 0.42 42 2.4
6 1999 427 0 50 _ 50 2.0
7 1989 395 0.58 58 1.7 ,? V L
8 1993 340 0.67 67 1.5 Teppt i c , Cave ?'`
9 1990 256 0.75 75 1.3 Dr.?vt k }
10 1 2 238 0.83 83 1.2
11 2000 201 0.92 92 1.1w?t:ud

APPENDIX B
ON-SITE CROSS-SECTIONAL DATA

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0
CONCEPTUAL MITIGATION REPORT
CAUSEY FARM MITIGATION SITE
GUILFORD COUNTY, NORTH CAROLINA
Prepared for:

Restoration Systems
1101 Haynes Street, Suite 203
Raleigh, North Carolina 27604
Prepared by:

EcoScience
EcoScience Corporation
1101 Haynes Street, Suite 101
Raleigh, North Carolina 27604
February 2002
R
NOV ?i 3 20'03
RALEIGH REGULATORY FIELD OFFICE

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MACTEC
November 3, 2003
Ms. Jean B. Manuele, Chief
Raleigh Regulatory Field Office
U.S. Department of the Army
Wilmington District Corps of Engineers
Regulatory Division
P.O. Box 1890
Wilmington, NC 28402-1890
Attention: Mr. John Thomas
RECEIVED
NOV 0 3 2003
RALEIGH REGULATORY FIELD OFFICE
Subject: Proposed Revision to Off-Site Component of Mitigation Plan for
Piedmont Triad International Airport
Section 404 Action ID No. 200021655
Section 401 Water Quality Certification No. 3428
Dear Ms. Manuele:
Pursuant to discussions of October 30, 2003 on behalf of the Piedmont Triad Airport Authority
(PTAA, applicant) we are hereby requesting your formal concurrence that the three off-site
stream restoration components located in Burlington (2,510 linear feet total), of the Wetland and
Stream Mitigation Plan for the referenced project, be replaced by an equal linear footage of
additional stream restoration at the Causey Farm site (to total 5,910 linear feet, if approved). It is
anticipated that the contiguous Causey Farm stream restoration project will provide better success
potential and more appropriate functional replacement for stream impacts than. the relatively
short, separate Burlington stream segments constrained by utilities, landfill, parklmunicipal
ordinances, adjacent landowners, and public use. We respectfully request that the attached
Conceptual Mitigation Report replace the Burlington and previously submitted Causey Farm
components of the Wetland and Stream Mitigation Plan for this project. Please do not hesitate to
contact me regarding the proposed revisions to the off-site mitigation component.
Sincerely,
MACTEC ENGINEERING AND CONSULTING, INC.
Richard B. Darling, C.E
Principal Environmental Scientist
Enclosures: Conceptual Mitigation Report for Causey Farm Mitigation Site
cc: Mickie L. Elmore, PTAA.
Kevin J. Baker, Baker & Associates.
RBD/KJB/MLE:rbd
P:W401 M Pmjac =253 MAVKodd'i=Wn\RgU st Modification Ldoc
MACTEC Engineering and Consulting
3301 Atlantic Avenue • Raleigh, NC 27604
919-876-0416 • Fax: [phone]

' TABLE OF CONTENTS
Paae
I
' LIST OF APPENDICES, FIGURES, AND TABLES ........................... . ii
1.0 INTRODUCTION ............................................ 1
2.0 RELEVANT FEATURES ........................................ 5
' 2.1 Physiography, Topography, and Land Use ...................... 5
2.2 Vegetation ........................................... 8
2.3 Stream Characterization .................................. 8
' 2.3.1 Stream Classification .............. 10
2.3.2 Dimension ...................................... 10
2.3.3 Profile ......................................... 12
2.3.4 Plan Form ....................................... 12
I' 2.4 Wetlands ........... ..... ............... ......... 13
0
3 CONCEPTUAL MITIGATION PLAN ................................ 15
' . . 15
I ......
3.1 Stream Restoration ... ................ .......
3.1.1 Channel Construction on New Location .................. 17
t 3.1.2 Bank Stabilization and Grade Control Structures ............. 17
3.1.3 Bankfull Bench Construction 18
1.4 Ford Removal and Construction .......... ...... .....
3 18
I' .
3.2 Wetland Restoration .................................... 19
3.3 Vegetative Planting ..................................... 19
.
. 21
4.0 .........
.
MONITORING PLAN .............................

I, 4.1 Stream Monitoring ......................................
4.2 Stream Success Criteria ........ .... ...................... 21
21
4.3 Wetland Monitoring ................ ........ • • • • . • • . • • .. 21
I 4.4 Wetland Success Criteria 22
'
`` ::::::::::::::::::: : :::::::: : ::
4.5 Vegetation Monitoring . • 22
Vegetation Success Criteria ...............................
4.6 23
' .
7 Contingency .........................................:
4 23
.
' 5.0' DISPENSATION OF THE PROPERTY .......... ...... • • • • • • ... • • • 24
6.0 REFERENCES ............................................... 25

?ll

0
1
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i
LIST OF FIGURES
Figure 1: Site Location ...................... ................... 2
Figure 2: Service Area ....................... ................... 3
Figure 3: Topography ....................... ........... ..... . 6
Figure 4: Land Use ......................... .................... 7
Figure 5: Hydric Soils ........ ............... ..... ............. 14
Figure 6: Conceptual Mitigation Plan .. ......... ................... 16
LIST OF TABLES
Table 1: Stream Geometry Attributes` .. ............................ 9
APPENDICES
Appendix A: Stream Gauge Data
Appendix B: On-Site Cross Section Data

1

A
t CONCEPTUAL MITIGATION REPORT
CAUSEY FARM MITIGATION SITE
' GUILFORD COUNTY, NORTH CAROLINA
1.0 INTRODUCTION
' Restoration Systems is currently evaluating stream and wetland restoration potential at a site
located in southeastern Guilford County, approximately 5 miles north of the Town of Liberty
' (Figure 1). The Causey Farm Mitigation Site encompasses approximately 288 acres of land
which is currently utilized for livestock grazing and hay production. Streams and wetlands
within the property have been cleared of native forest vegetation and are accessible to
t livestock, resulting in local disturbance to stream banks and wetland soil surfaces.
' The Site is located in U.S. Geological Service (USGS) Hydrological unit #03030002 of the
Cape Fear River Basin (Figure 2). This portion of the Cape Fear River Basin encompasses
portions of Guilford, Rockingham, Caswell, Alamance, Orange, Chatham, and Durham
Counties. Towns potentially serviced by this mitigation project include Greensboro,
Burlington, Reidsville, and Chapel Hill. The Site is intended to be developed to provide stream
' and riverine wetland mitigation credit to various projects in the region.
The purpose of this study is to determine potential restoration alternatives on the Causey
Farm Mitigation Site (hereafter referred to as the "Site"). This study is designed to address
the following objectives:
1 Provide plan views of the Site including land use constraints, topographic
'
)
features, wetlands, existing vegetation, or other features that may effect the
restoration project.
2) Classify on-site streams according to fluvial geomorphic attributes measured
' within each reach.
3) Develop a preliminary, conceptual plan of potential stream and wetland
mitigation activities.
4) Determine a monitoring strategy including mitigation success criteria.
5) ....Assess potential managers for the Site once mitigation activities are complete.
' This document is intended to provide information to agency personnel for discussion of
project parameters, including Site suitability and mitigation options / activities. Potential
restoration alternatives have been presented based primarily upon professional judgement.
1

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' If restoration is implemented on the Site, a detailed restoration plan will be prepared that
includes stream geometry measurements and wetland characterization from a reference
(relatively undisturbed) site in the region. Quantitative data collected during the design
' planning stage may affect mitigation activities proposed in this preliminary study.
4

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2_0 RELEVANT FEATURES
' 2.1 PHYSIOGRAPHY, TOPOGRAPHY, AND LAND USE
The Site is located in the southeastern corner of Guilford County, north of the Town of
_ Liberty (Figure 1). This portion of the state is underlain by the Carolina Slate Belt geologic
' formation within the Piedmont physiographic province of North Carolina. The
hydrophysiographic region is characterized by broad, rolling, interstream divides intermixed
with steeper slopes along well-defined drainage ways (Figure 3). This region is characterized
by moderately high rainfall with precipitation averaging 41 inches per year (NRCS 1977).
The Site encompasses reaches of two streams including North Prong Stinking Quarter Creek
and an associated unnamed tributary. Drainage areas for each of the streams are depicted
in Figure 3. Drainage basin size ranges from approximately 5.8 square miles for North Prong
Stinking Quarter Creek to approximately 1.0 square mile for the unnamed tributary at the
respective Site outfall. The unnamed tributary and its adjacent floodplain represent the
primary hydrologic feature of the Site. The unnamed tributary flows in a northerly direction
for approximately 6300 linear feet through the Site prior to its convergence with North Prong
' Stinking Quarter Creek near the northern property boundary (Figure 3).
The unnamed tributary is characterized as a second order stream extending through a
relatively narrow, steeply sloped valley (approximately 0.006 rise/run (based on USGS 7.5
minute quadrangles]). As the unnamed tributary descends towards North Prong Stinking
Quarter Creek, the valley widens and flattens to an average slope of approximately 0.0023
rise/run (based on USGS 7.5 minute quadrangles). The unnamed tributary watershed
upstream from the Site is characterized mainly by agricultural land use (livestock, row crops,
and hay production), low density residential development, and an airstrip / hanger complex
associated with the Causey Airport facility. Impervious surfaces appear to account for less
than 10 percent of the upstream land coverage.
On-site land use is characterized by livestock and hay production. A residential structure and
complex of barns and hay storage structures are located centrally within the Site (Figure 4).
The Site is primarily characterized by open pasture and agricultural fields with isolated
hardwood forest stands. Pasture is heavily grazed by livestock with stocking rates of
' approximately 5 animal units per acre. Livestock have access to a majority of the Site. No
exclusionary barriers occur adjacent to on-site streams or wetlands and livestock appear to
' have degraded stream banks and wetland soils.

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Raleigh, North Carolina 27605
Client:

Project:
CAUSEY FARMS
MITIGATION
SITE
GUILFORD COUNTY,
NORTH CAROLINA
Title:
TOPOGRAPHY
Dwn By
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Source: USGS 7.5 Minute Topo Maps (Climax. Kimesville. N.C.) ?f
NORTH PRONG STINKING
QUARTER CREEK WATERSHED
UNNAMED TRIBUTARY
WATERSHED

MAF FEB 2002
Ckd By: Scale:
WGL As Shown
ESC Project No.: 98-029
FIGURE
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CAUSEYFARMS
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SITE
GUILFORD COUNTY,
NORTH CAROLINA
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Title:
LAND USE
Dwn By. Dale:
MAF FEB2002
Ckd By: Scale:
WGL As Shown
ESC Project No 98-029
FIGURE
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' 2:2 VEGETATION
The Site is characterized by pasture land with a few isolated forest stands. The Site is
' heavily grazed and / or receives regular vegetative maintenance and does not appear to- be
advancing past a secondary seral community. Riparian fringes have little vegetative cover and
are dominated by species such as blackberry (Rubus argutas) and multiflora rose (Rosa
' multif/ora).
' Isolated patches of both hardwood forest and mixed pine forest occur in the floodplain south
of Smithwood Road which bisects the property from west to east. Livestock have access to
the mixed pine forest while the hardwood forest remains mostly fenced. The remaining
' forested communities are narrow strips of trees and shrubs growing along fence lines. The
primary species are eastern red cedar (Juniperus virginiana), persimmon (Diospyros virginiana),
sweetgum (Liquidambar styraciflua), and Chinese privet (Ligustrum sinense).
Pasture land dominates the Site and is characterized by native grasses with various invasive
' species such as pig weed (Chenopodium album), cocklebur (Xanthium strumarium), and
ragweed (Ambrosia artemisiifolia). Patches of shrubby species occur adjacent to the streams
' and tributaries; however, these species have been bush hogged (mowed) or manually cleared.
Shrubby species include blackberry, multiflora rose, black willow (Salixnigra), red maple (Acer
rubrum), and sweetgum. Multiple wetland depressional areas support a wet herbaceous
assemblage dominated by rushes and sedges (Juncus and Carex spp.).
Reforestation of hardwood species may be achievable within the entire on-site floodplain
complex. Forest species are expected to vary from bottomland hardwood forest to a more
mesic levee mixed forest based on topographic variations. Species composition should mimic
' reference forest measurements of similar undisturbed floodplains in the region. An ecological
approach to restoration is expected within the Site; therefore, a varied forest structure should
,' target habitat diversity.
. 2.3 STREAM CHARACTERIZATION
On-site streams have been characterization based on fluvial geomorphic principles (Rosgen
1996). Table 1 provides a summary of measured stream geometry attributes under existing
conditions (considered to be unstable) and a preliminary estimate of potentially stable stream
attributes. Establishment of specific design channel attributes will require measurement of
a reference (relatively undisturbed and stable) stream reach within the hydrophysiographic
' region. Preliminary estimates of stable stream attributes are based primarily upon data
observations along the existing reaches, regional curves (Harman et. al. 1999), and stream
gauge data collected in stream gauges in the vicinity of the Site.
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TABLE 1
STREAM GEOMETRY ATTRIBUTES
CAUSEY FARM MITIGATION SITE
S. S Sin Substrate Stream Type
aV9 BHR wbk11, o (riffle) (riselrun) (riselrun)
Reach Ai
(mi) = Ift) (ft) wdt•depth (ft2) (ft21

Existing Stream Attributes, North Prong Stinking Quarter Creek, Pie dmont Physiographic Province 0023 1
3
Average 23.3 2.4 278 323 114 57.4 1.0
11
66.1
55 0018 . .

86
38-93
- 5-17 61.9-70.3 38.72 --°--• -----•- Sand and
Silt E1C
9
6-32
13 1.9-2.8 228.342 277.369 76-1
Range 5.8 .
. .--_-- Average X1S. 1.3 -•- _
Average XlWbkn ' ?- ?- 13 15.2 5.4 2.7 ---
---
Range XIS.
11 16 13-17.3 3.6-8J L8 4.4 - .-

Range Xlwbkn "-•----
l Curves
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Stable Attributes based on 0018 0023 1.3
Average 26 2.5 278 323 260 130 1.0 9 66.1 ------

312

104-156

------

8-10 1,9-70.3

6 --- •-°
----._
------
-
Sand and

l
G
E
------ 228.342 277.369 182- rave
Range 5.8 -------
----

Average XISwa 1.3 _•....-
Average X1Wbkn ------- 11 12.4 10 5 •---_- --- ------- :j
-•--- Range XIS,
------ 8.7-13.2 10.6-14.1 7-12 4-6 ----- -
Range Xlw,ko ------

A A
M .I S. S"a ' Sin Substrate Stream Type
Wbkn D.9 wb
i
w?,
L..
? BHR wbknlDwg (riffle) (riffle) (rise/run) (rise/run)
Reach (n (riff le) (riff le) e
t
(ft) (ft) (ft) Ift) bankheiphtrato width-depth rato (ft2) (ft2)
(ft) (ft)
Existing Stream Attributes, Unnamed Tributary, Piedmont Physiographic Province 006 1.1
1
2 8 20.9 40 0055 .
Average 12 1.5 42 89 etitive
re
ti
t
di
N .
p
nc
,
s
o ---••-• •°--•- Sand and

7
3 1
1
38-112
80117 pattern of riffles and 1.0-1.5 5-12 20-21.4 12.8-88 ----- -

Silt E -D E1G
Range 7.6-15.1 .
. pools due to ditching S
1,0 .
Average X1
------- 3
5 8.3 and straightening ----•-
Average Xlwbkn °""'
.
activities

--- Range XIS„„
V11 "-""
------
3.2-9.3
6.7-10
----
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Range X/
l Curves
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Stable Attributes based on
009 006 1.5
99 134 67 1.0
9
20.9
•---••-
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Average 13.4 1.6 200

60
54-80
-------
8.10
20-21.4
------
•--•••-
---•••-
Sand
l and E
6
1-13
13 1.5-1.6 134-268 80-117 941 Grave
Range 1.0 .
. ------ Average XIS,,
Average Xlwbkn -""" .--._- 15 7.4 10 5 •------ -
. Range XIS„„
Range XMbe, 10-20 6.8.7 7-12 4-6 --•

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' 2.3.1 Stream Classification
Stream geometry and substrate data have been evaluated to orient stream restoration based
on a classification, utilizing fluvial geomorphic principles (Rosgen 1996). This classification
stratifies streams into comparable groups based on pattern, dimension, profile, and substrate
characteristics. Primary components of the classification include degree of entrenchment,
width/depth ratio, sinuosity, channel slope, and stream substrate composition. Stream.
classes associated with the Site include E, C, and G. Each stream type is modified by a
number from one through six (example: C5) denoting a stream type which indicates a
' substrate dominated by 1) bedrock, 2) boulders; 3) cobble, 4) gravel, 5) sand, or 6) silt/clay.
' Historically, on-site reaches may have been characterized as E4-type streams. E-type streams
are characterized as slightly entrenched, riffle-pool channels exhibiting high sinuosity (> 1.5).
' In North Carolina, E-type streams often occur in narrow to wide valleys with well- developed
alluvial floodplains (Valley Type VIII). E-type streams typically exhibit a sequence of riffles
and pools associated with a sinuous flow pattern. E-type channels are typically considered
stable. However, these streams are sensitive to disturbance and may rapidly convert to other
stream types.
Clearing of riparian vegetation, ditching and straightening activities, and hoof shear from
livestock entering the channels, have resulted in bank collapse and erosion of on-site reaches.
A majority of the on-site reaches are currently characterized as unstable, E/C- and E/G -type
channels which are systematically entrenching (G-type) and widening (F-type) due primarily
to the lack of deep rooted riparian vegetation. Bank materials are expected to continue to
erode until a stable floodplain has been scoured at the current elevation of the disturbed
streams.
A majority of the unnamed tributary reach appears to have been dredged, straightened, and
impacted by land clearing and livestock grazing. Grazing of livestock near stable streams (E
stream-type) typically leads to channel adjustments including increases in bank erosion,
width/depth ratio, stream gradient, and sediment supply. In addition, these impacts may lead
to decreases in channel sinuosity, meander width ratio, and sediment transport capacity
(Rosgen 1996). Straightening of channels induces erosion of bed and bank materials, which
exasperates sediment transport problems. The unnamed tributary is expected to continue to
erode and deposit sediment into receiving streams until a stable stream pattern has been
carved from the adjacent floodplain.
r
2.3.2 Dimension
Regional curves (Harman et.. a/. 1999) and field indicators of bankfull were utilized to
determine bankfull channel cross-sectional area in on-site reaches. The cross-sectional areas
1 10

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' were then utilized to determine the bankfull width, average bankfull depth, maximum depth,
and floodprone area of existing on-site channels. Using this method, a departure from
' stability could be estimated based on a comparison of existing and proposed (stable)
dimension variables.
Based on preliminary information, regional curves appear to overestimate the stable channel
cross-sectional area at the Site. The existing North Prong Stinking Quarter Creek is
characterized by a downstream cross-sectional area of approximately 38 square feet. This
reach of the creek is classified as an E-type channel with a bank-height-ratio of 1.0. The
channel does not exhibit excessive bank collapse and appears relatively stable. Regional
curves indicate that a cross-sectional area of greater than 70 square feet is expected to occur
in this reach.
Regional curve comparisons to on-site cross-sectional data prompted a search of nearby
stream gauges to verify the accuracy of regional curve predictions of bankfull discharge at.
' the gauged site. Three gauged streams were identified which appear to represent similar
drainage basin characteristics to the Site (Reedy Fork near Oak' Ridge, Rocky River at SR
' 1300, and Cane Creek Near Orange Grove). A peak annual discharge with a return interval
of 1.3 years has been utilized to predict bankfull discharge for this study.
' Regional curves predicted a 1.7 year return interval at two of the three gauges, indicating that
regional curves may slightly overestimate bankfull discharge and bankfull cross-sectional area
at the Site (gauge data is included in Appendix A). This information suggests that
measurement of a nearby reference (relatively undisturbed) reach is imperative for the
development of dimension variables to be constructed at the Site. However, for the purposes
' of this preliminary study, the regional curves have been utilized to predict stable channel
dimension variables (Table 1).
Based on regional curve estimations of cross-sectional area, it appears that various stream
bank erosional scenarios occur on-site. The majority of the Site is characterized by channel
incision which results in bank-height-ratios ranging from 1.0 to 1.5 (low bank height / bankfull
height). The down-cut may have resulted from a lack of adjacent deep-rooted riparian
vegetation. The down-cut has resulted in an incised channel that has begun to actively erode
channel banks below the effective rooting depth of existing riparian vegetation.
' These channels are expected to widen, causing the stream type to migrate towards an F-type
(widened gully) or disturbed C-type stream. However, until an active floodplain has been
carved, the channel is expected to remain an unstable, narrow and deep, E/G-type channel.

11

Based on this assessment, measures designed to reduce the bank height ratio and widen the
active floodplain are recommended along the channel.
2.3.3 Profile
_ Based on USGS quadrangles, the on-site valley slope measures approximately 0.0023 rise
/ run for North Prong Stinking Quarter Creek and 0.006 rise / run for the unnamed tributary.
Estimated valley slopes appear typical for the Piedmont physiographic region of North Carlina.
Water surface slopes were estimated by dividing the valley slope by channel sinuosity.
Sinuosity was inferred from aerial photography and /or Global Positioning System technology.
Sinuosity for North Prong Stinking Quarter Creek and its unnamed tributary were measured
' at 1.3• and 1.1, respectively. Calculated water surface slopes (Tables 1), range, from
approximately 0.0018 rise/run for North Prong Stinking Quarter Creek and 0.0055 rise / run
for the unnamed tributary.
Dredging and straightening of the unnamed tributary appears to have resulted in' an over
' steepened water surface-profile. Currently the water surface profile is approximately equal
to the valley surface slope; 0.0055 versus 0.006 (Table 1). In addition, channel
' modifications have obliterated the riffle-pool morphology characteristics of stable streams in
the region. Existing riffle slopes and pool slopes are, on, average, outside the range of
acceptable values considered for E-type streams in the region.
An over steepened water surface slope may be detrimental to on-site channels due to
increased erosive forces, altered secondary flow cells, and energy dissipation, possibly
' resulting in a step-pool channel morphology. Measures designed to reduce water surface
slope and restore riffle-and pool-slopes to suitable ranges is expected to be targeted
' throughout the unnamed tributary.
' 2.3.4 Plan Form
Aerial photography and in-field surveys were utilized to determine existing on-site plan form
variables. Once the existing plan form variables were identified, they were compared to ratios
of stable plan form variables based on fluvial geomorphic methods (Rosgen 1996). Using this
method, a departure from stability could then be estimated.
On-site channels support sinuosi ties ranging from between 1.1 to 1,3 (thalweg distance /
valley distance). The unnamed tributary sinuosity (1.1) is considered low (based on
geomorphic priciples) and North Prong Stinking Quarter Creek is considered moderate (1:3).
Stable sinuosities for E-type streams are expected to measure approximately 1.5. Reduced
sinuosities may result from bank collapse, channel obliteration, and dredging and straightening
' of channels. The unnamed tributary exhibits a belt width that ranges from 38 to 112 feet
1 12

11

1
1

11

n
' which is well below the expected range of 134 to 268 feet. The North Prong Stinking
Quarter Creek belt width ranges from 228 to 342 feet and appears to represent stable pattern
characteristics (based on regional curve estimates and reference ratios). On-site meander
wavelengths average approximately 114 feet on the North Prong Stinking Quarter Creek but
no distinct, repetitive pattern of sinuous riffle and / or pools were identifiable in the unnamed
tributary due to straightening activities. A stable maximum wavelength for the unnamed
tributary is expected to range between 94 to 160 feet with pool-to-pool spacings of
approximately 54 to 80 feet (Table 1).
Based on plan form variables, on-site channels include reaches that have been dredged and
' straightened or have been degraded by bank collapse and channel obliteration, thereby
reducing the beltwidth, meander length, and sinuosity of the reach. Mitigation efforts
targeting increases in sinuosity, beltwidth, and meander wavelength will be investigated along
' degraded sections to establish parameters within the range of potentially stable values for
these attributes.
2.4 WETLANDS
' Jurisdictional wetlands are defined by the presence of three criteria: hydrophytic vegetation,
hydric soils, and evidence of wetland hydrology during the growing season (DOA 1987). .
Portions of the Site historically supporting jurisdictional wetlands may have been characterized
by palustrine, forested wetlands and groundwater seeps which were seasonally flooded.
These wetland areas have been impacted by ditching, capping of spring heads, livestock
trampling, deforestation, and groundwater draw-down from stream channel downcutting.
Currently, on-site wetlands are characterized by a monoculture of sedges and rushes which
i are subjected to livestock trampling and heavy grazing pressure. Jurisdictional wetlands are
underlain by alluvial soils of the Wehadkee series which occur in a large patch-like network
throughout the on-site floodplains (Figure 5). Significant areas of jurisdictional wetlands
' occur adjacent to both the unnamed tributary and North Prong Stinking Quarter Creek.
' Based on aerial photography and on-site investigations, approximately 21 acres of the
floodplain currently are underlain by hydric soils that may have at one time supported
jurisdictional wetlands. Down-cutting of stream channels and ditching of spring heads may
have effectively lowered the adjacent groundwater table and soil saturation to below
jurisdictional thresholds. In addition, livestock trampling and regular maintenance of
agricultural fields have disturbed the natural state of these sensitive areas. Removal of
livestock and planting with native forested vegetation may allow the floodplain to preform
wetland functions such as flood-flow suppression, nutrient cycling, pollutant removal, and
' provide habitat for native species.
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EcoScience
Corporation
Raleigh, North Carolina 27605
Client:

Project:
CAUSEYFARMS
MITIGATION
SITE
GUILFORD COUNTY,
NORTH CAROLINA
Title:
HYDRIC SOILS
'd ?Y6P
v1°w` ' Dwn By Date:
S f
Ft MAF FEB2002
Ckd By. Scale:
WGL AS Shown
ESC Project No.: 98-029
FIGURE
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' 3_0 CONCEPTUAL MITIGATION PLAN
The primary goals of this mitigation plan include: 1.) construction of a stable, riffle-pool stream
' channel; 2) enhancement of the water quality functions in the on-site, upstream, and
downstream segments of North Prong Stinking Quarter Creek and its associated unnamed
tributaries; 3) creation of a natural vegetation buffer along on-site stream channels; 4)
' restoration of wildlife habitat associated with a riparian corridor / stable stream; and 5)
restoration of jurisdictional wetland hydrology to the floodplain of North Prong Stinking
Quarter Creek and the unnamed tributary.
Primary activities designed to restore the stream and wetland complex include: 1) stream
' restoration; 2) stream enhancement; 3) wetland restoration; and 4) vegetative community
restoration (Figure 6). The mitigation concept outlined in Figure 6 is expected to restore
' approximately 6840 linear feet of stream and 5 to 7 acres of jurisdictional wetland, along
with the subsequent enhancement of 3180 linear feet of stream and 14 to 16 acres of
' jurisdictional wetland.
3.1 STREAM RESTORATION
' Alternatives for stream restoration are designed to provide a stable stream channel and in-
stream aquatic habitat while protecting the adjacent stream banks from extensive erosion.
The alternatives proposed for this project are based primarily on professional judgement and
potentially stable stream attributes characteristic of the region.
' The majority of the on-site stream channels are classified as E/G stream types. The cross-
sectional area of on-site channels appear to have become unstable due to excessive bank
erosion from deforestation, livestock trampling, and channel dredging / straightening. In
addition, the bank height ratio of on-site channels, especially in the unnamed tributary,
appears to have been elevated from 1.0 (stable stream channel) to between 1 .0 and 1 .5.
' Bank collapse, channel straightening, and erosion also appears to have reduced sinuosity of
on-site channels to below the modal concept for stable E-type (highly sinuous) and C-type
(moderately sinuous) streams in the region.
Stream mitigation options should focus on the reduction of channel cross-sectional area
' (decreasing bank-height-ratio) and increasing sinuosity (reducing water surface slope). Stream
mitigation activities which may be utilized to achieve these results include: 1) the construction
of a channel on new location throughout most of the unnamed tributary; 2) bank stabilization
and installation of grade control structures within secondary tributaries and North Prong
Stinking Quarter Creek; and 3) the construction of bankfull benches near the upstream and
' downstream terminus of the Site. These mitigation activities are expected to result in
15

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EcoScrence
Corporation
Raleigh, North Carolina 27605
Client:
Project:
CAUSEY FARMS
MITIGATION
SITE
GUILFORD COUNTY,
NORTH CAROLINA
Title:
CONCEPTUAL
MITIGATION
PLAN
R ' a i 4,w Dwn By: Date:
MAF FEB 2002
` 4 soh Ckd By. Scale:
>?p WGL As Shown
ESC Project No.: 98-029
FIGURE
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t approximately 6840 linear feet of stream restoration and 3180 linear feet of stream
enhancement (Figure 6).
' 3.1.1 Channel Construction on New Location
_ Channel construction on new location is expected to occur predominantly in the unnamed
tributary due to limited concerns of hydrologic trespass. Channel construction is expected
to entail the preparation of a belt width corridor prior to channel excavation. Belt width
' corridor preparation will entail channel staking and any necessary grading prior to channel
excavation. Spoil material excavated during the grading and channel excavation process is
expected to be stockpiled adjacent to the existing unnamed tributary channel that will be
abandoned and then backfilled.
' Once belt width corridor preparation is complete, the proposed channel will be excavated to
the average width, depth, and cross-sectional area derived from reference reach studies and
detailed measurements of on-site streams. The stream banks and local belt width area of
' constructed channels will be immediately planted with shrub and herbaceous vegetation.
Black willow shrubs may be removed from the banks of the abandoned channel and
' stockpiled during clearing to be replanted in the new stream channel. Root mats may also
be selectively removed from adjacent areas and placed as erosion control features on channel
banks.
Particular attention will be directed toward providing vegetative cover and root growth along
t the outer bends of each stream meander. Available root mats or biodegradable, erosion
control matting may be embedded into the break-in-slope to promote more rapid development
of an overhanging bank. Willow stakes will be collected on-site and inserted through the root
' / erosion mat into the underlying soil. The reconstructed channel and vegetation will be
allowed to stabilize for a minimum of four months during the growing season prior to
' diversion of flow. Flow will be diverted incrementally to allow for adaption within the
reconstructed channel.
' 3.1.2 Bank Stabilization and the Installation of Grade Control Structures
Bank stabilization may be performed along eroding outer bends within existing channel
' reaches of North Prong Stinking Quarter Creek, the hardwood forest section of the unnamed
tributary, and two secondary tributaries entering the unnamed tributary from the east (Figure
6). Particular attention should be placed on outer bends of eroding pools or excessively
eroding banks. Bank slopes will be protected through placement of appropriate structures
such as brush mattresses, live brush layering, matting, rock toe protection, root wads, cross-
1 vanes, and / or J-Hook vanes.
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' Grade control structures may be placed in the channel to elevate local water surface profiles
in the channel, potentially flattening the water energy slope or gradient. The structures would
likely consist of boulder-size rock vanes or step-pool devices designed primarily to direct
stream energy into the center of the channel and away from actively eroding banks. In
_ addition, the structures would be placed in relatively straight reaches to provide secondary
(perpendicular) flow cells during bankfull events.
' 3.1.3 Bankfull Bench Construction
The potential excavation of a bankfull floodplain bench in North Prong Stinking Quarter Creek
is expected to: 1) remove the eroding material and collapsing banks; 2) promote overbank
' flooding during bankfull flood events; 3) reduce the erosive potential of flood waters; and 4)
increase the width of the active floodplain. After excavation, the bench would provide a
' relatively level floodplain surface which could be stabilized with suitable erosion control
measures. Planting of the bench with native floodplain vegetation may reduce erosion of
bench sediments, reduce flow velocities in flood waters, filter pollutants, and provide wildlife
habitat.
' Floodplain benches may be constructed in North Prong Stinking Quarter Creek and reaches
where hydrologic trespass may preclude increased water surface elevation. Stream reaches
that may receive floodplain bankfull benches are located at the upper extent of on-site
streams, near property boundaries, and at the Site outfall.
' 3.1.4 Ford Removal and Construction
Several on-site fords have been identified in both the unnamed tributary and North Prong
Stinking Quarter Creek. These existing fords have resulted in impoundment of on-site
' streams and obliteration of stream banks; therefore, removal of the fords is proposed within
the Site. Replacement fords may be constructed to allow the passage of cattle and or
' vehicles. The fords are expected to consist of a shallow depression in the stream banks
where vehicular crossings can be made. Flexibility in the location of the fords exists and may
be changed upon request by landowners or on-site construction managers. The fords shall
' be constructed of hydraulically stable rip-rap or suitable rock and should be large enough to
handle the weight of anticipated vehicular traffic. Approach grades to the fords should be
approximately 30 feet in length and constructed of hard, weather-resistant crushed rock or
other permeable material which is free of fines. The bed elevation should be equal to the bed
elevation of the design stream channel above and below the fords to reduce the risk of
headcutting.

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3.2 WETLAND RESTORATION
Alternatives for wetland restoration are designed to restore a fully functioning wetland system
' which will provide surface water storage, nutrient cycling, removal of imported elements and
compounds, and will create a variety and abundance of wildlife habitat. Wetland restoration
alternatives are based primarily on professional judgement and a reference wetland is
' expected to be measured to determine vegetative features, micro- and macro- topographic
variations, and soil structure components to be targeted during development of the Site.
Portions of the Site underlain by hydric soil have been impacted by ditching of natural springs,
channel incision, vegetative clearing, livestock grazing, and earth movement associated with
' agricultural practices. These areas are characterized by a near mono-culture community of
sedges, grasses, and rushes, under severe impact from soil compaction by livestock
' trampling. Wetland mitigation options should focus on the restoration of vegetative
communities, elevating groundwater tables to jurisdictional conditions, and the re-
establishment of soil structure and micro-topographic variations within the existing floodplain.
Restoration of wetland hydrology and wetland soil attributes may involve: 1) excavation and
' grading of elevated spoil and sediment embankments; 2) placement of impervious channel
plugs along abandoned reaches; 3) backfilling of entrenched stream reaches; and 4)
scarification of pasture soils prior to planting. In addition, the construction of (or provisions
' for) surface water storage depressions (ephemeral pools) also adds an important component
of groundwater restoration activities. These mitigation activities are expected to result in the
restoration of approximately 5 to 7 acres and enhancement of approximately 14 to 16 acres
of jurisdictional wetland at the Site.
' 3.3 VEGETATIVE PLANTING
Deep-rooted, riparian vegetation will be restored within the entire floodplain complex of both
' the unnamed tributary and North Prong Stinking Quarter Creek. Planting vegetation on
cleared stream banks is proposed to re-establish vegetation community patterns within the
stream corridor, associated side slopes, and transition areas. Vegetating the floodplain and
stream banks is expected to provide stream bank stability, shade and cool surface waters,
filter pollutants from adjacent runoff, and provide habitat for area wildlife. The vegetated
stream buffer will extend to a minimum of 50 feet on both sides of the stream. Scarification
of floodplain surfaces will be required prior to vegetation planting.
' Variations in vegetative planting may occur based on topographic locations and hydraulic
conditions of the soil. Vegetative species composition should mimic reference forest data and
' on-site observations. Species expected for this project may include the following elements.
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Shrubs / Trees
1 . Green Ash (Fraxinus pennsylvanica)
' 2. Northern Red Oak (Quercus rubra)
3. American Sycamore (Platanus occidentalis)
4. American Elm (Ulmus americana)
7 5. Ironwood (Carpinus caroliniana)
6. Black Cherry (Prunus serotina)
' 7. Smooth Black Haw (Virburnum prunifolium)
8. Black Gum (Nyssa Sylvatica)
' Stream-S
1.
' 2.
3.
4.
5.
ide Assemblage
Black Willow (Salix nigra)
Box Elder (Acer negundo)
Ironwood (Carpinus caroliniana)
River Birch (Betula nigra)
American Sycamore (Platanus occidentalis)
Stream-Side Shrub Assemblage
1. Tag Alder (Alnus
2. Buttonbush (Ceph
' 3. Elderberry (Sambu
4. Arrow-wood Vibu
5. Possumhaw Vibur
6. Bankers Dwarf W
7. Black Willow (Sall
Approximately 45 acres of on-sit
' construction. Species distribut
detailed mitigation planning pha
serrula to )
alanthus occidentalis)
cus canadensis)
rnum (Viburnum dentatum)
num (Viburnum nudum)
illow (Salix cotteli)
'x nigra)

e floodplain is expected to be re-vegetated during mitigation
ion and densities are expected to be determined during the
se of the project.

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4_0 MONITORING PLAN
Monitoring of Site restoration efforts is expected to be performed until success criteria are
fulfilled. A monitoring plan and detailed success criteria are expected to be developed during
the detailed mitigation planning phase of the project. However, some guidelines which may
be utilized to develop a monitoring strategy and success criteria follow.
4.1 STREAM MONITORING
'
Annual fall monitoring may include development of a channel plan view, channel cross-
sections on riffles and pools, pebble counts, and a water surface profile of the channel. The
data may be presented in graphic and tabular format. Data to be presented is expected to
' include: 1) cross-sectional area; 2) bankfull width; 3) average depth; 4) maximum depth; 5)
width / depth ratio; 6) meander wavelength; 7) belt width; 8) water surface slope; 9)
sinuosity; and 10) stream substrate composition. The streams should subsequently be
classified according to stream geometry and substrate (Rosgen 1996). Significant changes
in channel morphology are expected to be tracked and reported by comparing data in each
' successive monitoring year.
' 4.2 STREAM SUCCESS CRITERIA
Success criteria for stream restoration may include: 1) successful classification of the reach
as a functioning stream system (Rosgen 1996); 2) channel stability indicative of a stable
' stream system; and 3) development of diagnostic biological communities over time.
The channel configuration may be measured on an annual basis to track changes in channel
geometry, profile, or substrate. These data are expected to be utilized to determine the
success in restoring stream channel stability. Specifically, the width / depth ratio should
' remain at or below a value of 14 in each monitoring year. In addition the channel should not
become incised relative to the adjacent floodplain. Modifications to the channel should be
performed to increase or decrease the sediment transport capacity, or other unstable
attributes, as needed. If the stream channel is down-cutting or the channel width is enlarging
due to bank erosion, additional bank or slope stabilization methods may be employed.
4.3 WETLAND MONITORING
Groundwater gauges are expected to be installed in accordance with specifications in U.S.
Corps of Engineers', Installing Monitoring Wells/Piezometers in Wetlands (WRPTechnical Note
HY-IA-3.1, August 1993). Monitoring gauges should be set to a predetermined depth of
' approximately 40 inches below the soil surface in order to obtain a more accurate depiction
of watertable fluctuations. Hydrological sampling may be performed on-site and' within
reference areas throughout the year to compare pre- and post-construction conditions.
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' 4.4 WETLAND SUCCESS CRITERIA
Target hydrological characteristics may include a minimum regulatory wetland hydrology
criteria based upon reference groundwater modeling. Evaluation of success criteria is
expected to be supplemented by groundwater gauge data and comparison between
restoration and reference areas.
Target hydrological characteristics during years with average rainfall include saturation or
' inundation (free water) within one foot of the soil surface for at least 12.5 percent of the
growing season. Upper landscape reaches and hummocks within wetland areas may exhibit
surface saturation / inundation between 5 percent and 12.5 percent of the growing season.
These 5 to 12.5 percent areas are expected to support hydrophytic vegetation within hydric
soils. If wetland parameters are marginal as indicated by vegetation and hydrology
monitoring, consultation with U.S. Army Corps of Engineers (COE) personnel will be
undertaken to determine jurisdictional extent in these areas.
' 4.5 VEGETATION MONITORING
Restoration monitoring procedures for vegetation are expected to'be designed in accordance
' with U.S. Environmental Protection Agency (EPA) guidelines enumerated in (EPA 1990) and
(DOA 1994). A general discussion of the restoration monitoring program is provided.
' After planting has been completed in winter or early spring, an initial evaluation may be
performed to verify planting methods and to determine initial species composition and
' density. Supplemental planting and additional site modifications are expected to be
implemented, if necessary.
During the first year, vegetation should receive cursory, visual evaluation on a periodic basis
to ascertain the degree of overtopping of planted elements by nuisance species.
Subsequently, quantitative sampling of vegetation should be performed between September
1 and October 30 after each growing season until the vegetation success criterion is
' achieved.
During quantitative vegetation sampling in early fall of the first year, sample plots may be
randomly placed within the Site. In each sample plot, vegetation parameters to be monitored
may include species composition and species density. Visual observations of the percent
cover of shrub and herbaceous species are expected to be recorded.

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' 4.6 VEGETATION SUCCESS CRITERIA
Success criteria have been established to verify that the vegetation component supports
community elements necessary for floodplain forest development. Success criteria may be
' dependent upon the density and growth of characteristic forest species.
' Guidelines including survivorship of approximately 320 stems per acre in the first three
monitoring years may be utilized. Subsequently, 290 character tree species per acre may be
' surviving in year 4, and 260 tree species per acre in year 5. Planted species should represent
a minimum of 30 percent of the required stem per acre total (96 stems/acre). Each naturally
recruited character species may represent up to 10 percent of the required stem per acre
total. In essence, seven naturally recruited character species may represent a maximum of
70 percent of the required stem / acre total. Additional stems of naturally recruited species
above the 10 percent - 70 percent thresholds are discarded from the statistical analysis.
If vegetation success criteria are not achieved based on average density calculations from
' combined plots over the entire restoration area, supplemental planting may be performed with
tree species approved by regulatory agencies. Supplemental planting may be performed as
' needed until achievement of vegetation success criteria.
No quantitative sampling requirements are proposed for herb assemblages as part of the
vegetation success criteria. Development of floodplain forests over several decades are
expected to dictate the success in migration and establishment of desired understory and
groundcover populations. Visual estimates of the percent cover of herbaceous species and
i photographic evidence may be reported for information purposes.
4.7 CONTINGENCY
In the event that vegetation, hydrology, and / or stream success criteria are not fulfilled, a
mechanism for contingency may be implemented. For vegetation contingency, replanting and
extended monitoring periods will be implemented if community restoration does not fulfill
minimum species density and distribution requirements.
Stream reconstruction failure may occur due to increased sediment and discharge during
development within the upper watershed. Stream contingency will likely include identification
' and modification of upstream sediment sources, additional stabilization of stream banks, and
re-establishment of stream substrates required to support target aquatic communities.
Recommendations for stream contingency will also be solicited, implemented, and monitored
until the Stream Success Criteria are achieved.

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' Wetland hydrology failure may occur due to insufficient hydrologic flow and or unpredictable
hydraulic conductivities of disturbed soils. Wetland contingency may likely include
modifications of floodplain and or subsurface soils required to support target hydrologic
' regimes.
' Recommendations for vegetation, stream, and wetland contingency is expected to be
solicited, implemented, and monitored until the Success Criteria are achieved.
5.0 DISPENSATION OF PROPERTY
Restoration Systems will maintain the conservation easement within the Site until all
mitigation activities are completed and the mitigation site has been deemed successful. Once
the Site has been developed, the easement may be deeded to a land trust organization or
community entity suitable to the regulatory agencies. A likely candidate for perpetual
maintenance of the easement is Guilford County. The Site may be incorporated into the
Guilford County Division Parks and Recreation for use in environmental education and / or
' open space.
The current landowner (Mr. Trager) is expected to retain ownership of the properties. The
' conservation easement is expected to be transferred perpetually with the properties upon sale
or development of the property. Covenants and / or restrictions on the deed will be included
that will ensure adequate management and protection of the Site in perpetuity.

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' 6.0 REFERENCES
Department of the Army (DOA). 1987. Corps of Engineers Wetlands Delineation Manual.
Tech. Rpt. Y-87-1, Waterways Experiment Station, COE, Vicksburg, MS.
Department of the Army (DOA). 1994. Corps of Engineers Wilmington District.
Compensatory Hardwood Mitigation Guidelines (12/8/93).
Environmental Protection Agency (EPA). 1990. Mitigation Site Type Classification (MiST).
EPA Workshop, August 13-15, 1989. EPA Region IV and Hardwood Research
Cooperative, NCSU, Raleigh, North Carolina.
Harman, W.A., G.D. Jennings, J.M. Patterson, D.R. Clinton, L.A. O'Hara, A. Jessup, R.
' Everhart. 1999. Bankfull Hydraulic Geometry Relationships for North Carolina
Streams. N.C. State University, Raleigh, North Carolina.
' Natural Resource Conservation Service (NRCS). 1977. Soil Survey of Guilford County, North
Carolina. U.S. Department of Agriculture.
Rosgen, D. 1996. Applied River Morphology. Wildland Hydrology (Publisher). Pagosa
Springs, Colorado.
Rosgen, D. 1996b. "Classification of Natural Rivers: Reply to the comments by J.R. Miller
' and J.B. Ritter." Catena. 27:301-307

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1 APPENDIX A
STREAM GAUGE DATA

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' Peak Streamflow
Reedy Fork Near Oak Ridge, NC
USGS Station #02093800
Drainage Area 20.6 square miles

Water Discharge Exceedance Exceedance
Year (cfs) Probability Probability %

eturn
Interval
(years)
' 1 1960 3950 0.02 2 46.0
2 1972 2990 0.04 4 23.0
3 1979 2880 0.07 7 15.3
4 1978 2350 0.09 9 11.5
5 1996 2330 0.11 11 9.2
' 6 1984 2090 0.13 13 7.7
7 2000 2050 0.15 15 6.6
8 1997 1880 0.17 - 17 5.8
9 1993 1590 0.20 20 5.1
10 1969 1500 0.22 22 4.6
' 11 1959 1460 0.24 24 4.2
12 1991 1440 0.26 26 3.8
13 1989 1310 0.28 28 3.5
14 1973 1250 0.30 30 3.3
15 1987 1250 0.33 33 3.1
' 16 1965 1210 0.35 35 2.9
17 1977 1210 0.37 37 2.7
18 1975 1040 0.39 39 2.6
19
20 1982
1986 995
965 0.41
0.43 41
43 2.4
2.3
' 21 1963 960 0.46 46 2.2
22 1974 957 0.48 48 2.1
23 1990 962 0.50 60 2.0
24
25 1992
1970 864
858 0.52
0.54 52
54 1.9
1.8
' 26 1994
- 837
MMM 0.57 57 1.8
M
28 9905
E
1962 MI
756 0.61 61 1.6
29
30 1956
1998 746
741 0.63
0.65 63
65 1.6
1.5
31 1971 729 0.67 67 1.5
32 1957 719 0.70 70 1.4
33 1980 670 -0.72 72 1.4
34 1966 664 0.74 74 1.4
35 1983 664 0.76 76• 1.3
r3
37 n
1995 w'
582
0.80
80
1.2
38 1981 517 0.83 83 1.2
39 1999 412 0.85 85 1.2
40 1961 408 0.87 87 1.2
' 41 1964 388 0.89 89 1.1
42 1976 379 0.91 91 1.1
43 1985 378 0.93 93 1.1
44 1968 148 0.96 96 1.0
' 45 1967 147 0.98 98 1.0

"Jk '?Gby
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Peak StreamfloW
Rocky River at SR1300 Near Crutchfield Crossroads, NC
USGS Station #0210166029
Drainage Area 7.4 square miles
Return
Water Discharge Exceedance Exceedance Interval
Year (cfs) Probability Probability % (years)
1 1998 864 0.08 8 12.0
2 1995 698 0.17 17 6.0
' 3 1997 673 0.25 25 4.0
4 1991 469 0.33 33 3.0
5 1994 429 0.42 42 2.4
6 1999 427 0 50 2.0
7 1989 395 0.58 58 1.7 Gz ,? V
8 1993 340 0.67 67 1.5
' 9 1990 256 0.75 75 1.3 Lkvi k i
10 1 2 238 0.83 83 1.2
11 2000 201 0.92 92 1.1wwi

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Peak Streamflow
Cane Creek Near Orange Grove, NC
USGS Station #02096846
Drainage Area 7.5 square miles
Return
Water Discharge Exceedance Exceedance Interval
Year (cfs) Probability Probability % (years)
' 1 1996 2060 0.08 8 13.0
2 1993 1740 0.15 15 6.5
' 3
4 1995
1998 1280
1110 0.23
0.31 23
31 4.3
3.3
5 2000 903 0.38 38 2.6
6
7 1989
1994 864
725 0.46
0.54 46
54 2.2
1.9
8 1999 689 0.62 62 1.6 C??
9
10 1991
1997 516
458 0.69
0.77 69 1.4
1.3 e?
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1992 433 0.85 85 1.2
12 1990 421 0.92 92 1.1

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APPENDIX B
ON-SITE CROSS-SECTIONAL DATA

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Baker and Associates
A Unit of Michael Baker Corporation
200 CentrePort Drive, Suite 225
Greensboro, NC 27409
[phone]
FAX [phone]
October 30, 2003
Mr. Todd St. John
North Carolina Department of Environmental and Natural Resources
Division of Water Quality - Wetlands Unit
2321 Crabtree Boulevard
Raleigh, NC 27604-2260
Subject: FedEx Development Program
Stormwater Management Review
Dear Mr. St. John:
WETLANDS / 401 GROUP
OCT 3 1 2003
WATER QUALITY SECTION
Per your request, we are providing additional information for the subject effort. We have
enclosed the following:
¦ Drawing depicting the stormwater ponds, associated water quality BMP's, and the
surrounding natural terrain
¦ Signed/notarized maintenance agreement for the proposed ponds
¦ Surface Area Drainage Area (SADA) calculations for each system
¦ Detail of Baffle tie-ins
¦ Revised detail (typical section) of flow spreaders
The proposed system is a modification of the standard BMP manual, as it includes the use of
natural and restored wetlands, as well as a modified dry pond that will function like a non-marsh
wetland. The proposed system is meant to function like an extended detention wetland. It
includes similar design features, such as a 2-5 day detention of the runoff from a 1-inch rain. It
provides more surface area than would be required for an extended detension wetland, without
the marsh-type characteristics that could endanger aircraft.
As we have discussed, during construction, these ponds will function in an E&S role. They will
only truly begin to function as stormwater management ponds upon completion of the proposed
FedEx development, which is scheduled to occur in the 2008-2009 timeframe. In response to
specific issues discussed, we offer the following solutions for the final stormwater management
plan:
1.) Flow Spreaders have been reconfigured per our discussion. These will be further
lengthened in the field, if such modification is approved by USAGE.
2.) Pond F2 Emergency Spillway has been relocated per our discussion.
3.) The bottom of the pond will be graded per your suggestion, with small recesses to
form ephemeral ponds. The area will be graded, ripped and topsoiled with stockpiled
material to encourage vegetative growth. Specifically, per your suggestion, we
propose that approximately 50% of the basin will have small depressions not larger
than 20' x 20', and average depth of 3-6 inches. Additional small pools not larger
than 10' x 10' and average depth of 3 feet will be provide on approximately 100 foot
centers to encourage mosquito control species. The entire basin floor of the ponds
will be planted with herbaceous and shrubby vegetation as approved by DWQ.
Approximately 20%0 of the basin floors will be planted with shrubby wet tolerant
vegetation to discourage unwanted wildlife on 3-5 foot centers depending on plant
size. MACTEC has provided a suggested planting list that is included with this
submittal.
4.) If permitted by the USACE, logs will be placed near the toe of the embankments, and
in the natural wetlands to assist with dispersion of higher flows.
5.) Sides of the ponds incorporate 2:1 slopes as recommended by FAA to deter wildlife.
The system will use a combination of dry ponds modified per item three, level spreaders, natural
buffer area, and natural wetlands to achieve water quality standards. The attached SADA
calculations are based upon DENR criteria for Extended Detention Wetlands, and show that more
than adequate area is available.
Please feel free to call me at 336/931-1500 with any questions.
Sincerely,
BAKER AND ASSOCIATES
evin J. Baker, P.E.
Assistant Vice President
Enclosures
cc: Cindi Karoli, DWQ (w/o Enclosure)
M. L. Elmore, PTAA (w/o Enclosure)
WETLAND-type DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wetland-type detention basin system is defined as the wetland-type detention basin, pretreatment
including energy dissipators and flow spreaders.
Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, re-seed as necessary to maintain good vegetative cover, mow
vegetative cover on side slopes, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the detention basin system semi-annually or when depth is reduced
to 75% of the original design depth. Removed sediment shall be disposed of in an appropriate manner
and shall be handled in a manner that will not adversely impact water quality (i.e. stockpiling near a
detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
Natural and restored wetlands will be inspected every six months. Corrective action will be taken for any
areas of erosion or concentrated flow. Heavy equipment will be used for these repairs only when so
approved by NCDENR and USACE. During project construction, and until the site is release by the DLR,
the natural wetlands, constructed wetlands, and wetland buffers will be inspected every quarter for signs
of erosion and sediment accumulation. Repairs to eroded areas and removal of accumulated sediment
shall be conducted as needed.
When basins are maintained, basin bottoms will be returned to the grades shown on the as-built plans.
The disturbed surface will be ripped if compacted, and re-vegetated. As necessary, the top 0.3 feet of the
basin bottom will be stockpiled and re-applied to the disturbed area to achieve final grade, or the
disturbed area shall be re-vegetated according to the vegetation planting plan.
5. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
6. All components of the detention basin system shall be maintained in good working order.
7. Flow spreaders that provide diffuse flow shall be maintained every six months. All accumulated sediment
and debris shall be removed from the structure, and a level elevation shall be maintained across the
entire flow spreading structure. Any down gradient erosion must be repaired and/or replanted as
necessary.
Page 1 of 2
acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.
Print name: MICV4e, L e:tmorz
I, SCE ,? , a Notary Public for the State of C 'rUl I Vhi
County of 'u , do her9by certify that Vh.Di*`
personally appeared before me this day of K)??bet- and acknowledge the due
execution of the forgoing wetland-type detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
My commission expires o 93 ? 60
Page 2 of 2
Title: 1 ??'D ?VLo?,th?T
Address: 64 15 V?2KYAnt f,.X, IO ?f?f?F.?t?3 ego W401
(.!.14-011

October 30, 2003
Mr. Todd St. John
North Carolina Department of Environmental and Natural Resources
Division of Water Quality - Wetlands Unit
2321 Crabtree Boulevard
Raleigh, NC 27604-2260
Subject: FedEx Development Program
Stormwater Management Review
Dear Mr. St. John:
Baker and Associates
A Unit of Michael Baker Corporation
200 CentrePort Drive, Suite 225
Greensboro, NC 27409
[phone]
FAX [phone]
WEI fwfts/401 GROUP
OCT 31 2003
WATER QUALITysECT
ION
Per your request, we are providing additional information for the subject effort. We have
enclosed the following:
¦ Drawing depicting the stormwater ponds, associated water quality BMP's, and the
surrounding natural terrain
¦ Signed/notarized maintenance agreement for the proposed ponds
¦ Surface Area Drainage Area (SADA) calculations for each system
¦ Detail of Baffle tie-ins
¦ Revised detail (typical section) of flow spreaders
The proposed system is a modification of the standard BMP manual, as it includes the use of
natural and restored wetlands, as well as a modified dry pond that will function like a non-marsh
wetland. The proposed system is meant to function like an extended detention wetland. It
includes similar design features, such as a 2-5 day detention of the runoff from a 1-inch rain. It
provides more surface area than would be required for an extended detention wetland, without
the marsh-type characteristics that could endanger aircraft.
As we have discussed, during construction, these ponds will function in an E&S role. They will
only truly begin to function as stormwater management ponds upon completion of the proposed
FedEx development, which is scheduled to occur in the 2008-2009 timeframe. In response to
specific issues discussed, we offer the following solutions for the final stormwater management
plan:
1.) Flow Spreaders have been reconfigured per our discussion. These will be further
lengthened in the field, if such modification is approved by USACE.
2.) Pond F2 Emergency Spillway has been relocated per our discussion.
3.) The bottom of the pond will be graded per your suggestion, with small recesses to
form ephemeral ponds. The area will be graded, ripped and topsoiled with stockpiled

material to encourage vegetative growth. Specifically, per your suggestion, we
propose that approximately 50% of the basin will have small depressions not larger
than 20' x 20', and average depth of 3-6 inches. Additional small pools not larger
than 10' x 10' and average depth of 3 feet will be provide on approximately 100 foot
centers to encourage mosquito control species. The entire basin floor of the ponds
will be planted with herbaceous and shrubby vegetation as approved by DWQ.
Approximately 20% of the basin floors will be planted with shrubby wet tolerant
vegetation to discourage unwanted wildlife on 3-5 foot centers depending on plant
size. MACTEC has provided a suggested planting list that is included with this
submittal.
4.) If permitted by the USACE, logs will be placed near the toe of the embankments, and
in the natural wetlands to assist with dispersion of higher flows.
5.) Sides of the ponds incorporate 2:1 slopes as recommended by FAA to deter wildlife.
The system will use a combination of dry ponds modified per item three, level spreaders, natural
buffer area, and natural wetlands to achieve water quality standards. The attached SADA
calculations are based upon DENR criteria for Extended Detention Wetlands, and show that more
than adequate area is available.
Please feel free to call me at 336/931-1500 with any questions.
Sincerely,
BAKER AND ASSOCIATES
4evin J. Baker, P.E.
Assistant Vice President
Enclosures
cc: Cindi Karoli, DWQ (w/o Enclosure) ?---
M. L. Elmore, PTAA (w/o Enclosure)
10/30/2003 THU 13;51 FAX [phone] Baker and Associates
LC : fvt.IF,
Engineering and Energy
Baker and Associates Fax Transmittal Letter
A&Wsmo0fAi &d8alta Cwp abw
Baker and Associates
200 CentrePod Drive, Suite 225
Greensboro, NC 27409
[phone] OUR TELEFAX NO. IS: [phone]
jo f 3a ?d - -?0 :'1
Date:
To: (Company) f0 'mil - cJ d ?P- -
(AttenUon) WL-TW QS
Receiving Telecopier No.
From:
gooliou3
IIMtGiti?- L?f" 1!?
TOTAL NUMBER OF PAGES 3 (INCLUDING THIS TRANSMITTAL PAGE) X08 - dz?
IF YOU DO NOT RECEIVE THE NUMBER OF PAGES INDICATED, PLEASE
CONTACT OUR OFFICE AS SOON AS POSSIBLE.
i
UAAXM7W#1"7U•81FAXIitAMJ)0C . i.,. ` :: -....•::.:.:,: -.::e:.-ti :,.
10/30/2003 THU 13:51 FAI 336 931 1501 Baker and Associates 4UUI/003
00, 30, 2003 11:42AM PIEDMONT TRIAD AIR DEVELOPMENT No-0347 P. 1
WETLAND-type DETENTION BASIN OPERATION AND MAINTENANCF- AGREEMENT
The wetland-type detention basin system Is defined as the wetland-type detention basin, pretreatment
including energy dissipators and flow spreaders.
Maintenance activities shall be performed as foilows.
1. After every significant runoff producing rainfall event and at least monthly:
a. Inspect the detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition-
b, Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, reseed as necessary to maintain good vegetative cover, mow
vegetative cover on side slopes, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the detention basin system serni?nnually or when depth is reduced
to 7516 of the original design depth. Removed sediment shall be disposed of in an appropriate manner
and shall be handled in a manner that will not adversely impact water quality (i.e. stockpiling near a
detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments-
Natural and restored wetlands will be inspected every six months. Corrective action will be taken for any
areas of erosion or concentrated flow. Heavy equipment will be used for these repairs only when so
approved by NCDENR and USACE. During project construction, and until the site is release by the DLR,
the natural wetlands, constructed wetlands, and wetland buffers will be Inspected every quarter for signs
of erosion and sediment accumulation. Repairs to eroded areas and removal of accumulated sediment
shall be conducted as needed.
When basins are maintained, basin bottoms will be returned to the grades shown on the as-built plans.
The disturbed surface will be ripped if compacted, and re vegetated. As necessary, the top 0,3 feet of the
basin bottom will be stockpiled and re-applied to the disturbed area to achieve final grade, or the
disturbed area shall be re-vegetated according to the vegetation planting plan.
5. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
8. All components of the detention basin system shall be maintained in good working order.
7, Flow spreaders that provide diffuse Clow shall be maintained every six months. All accumulated sediment
and debris shall be removed from the structure, and a level elevation shall be maintained across the
entire flow spreading structure- Any down gradient erosion must be repaired and/or replanted as
necessary.
pw l of 2
10/30/2003 THU 13:51 FAI 336 931 1501 Baker and Associates 4UUS/UUJ
Oct-30. 2003 11:42AM PIEDMONT TRIAD AIR DEVELOPMENT No-0347 P. 2
1 acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or priorto any
changes to the system or responsible party.
Print
t, 1 + a Notary Public for the State of Q f`t7 I
County of ?u 1 do hergby certify that -it
personally appeared before me this day of and acknowledge the due
execution of the forgoing wetland-type detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
My commission expires
Page 2 of 2
Tide: 9 92t
Address: ,,,f 15 IYA '?LY acs aka _74Q`i
10/30/2003 THU 11:44 FAI 336 931 1501 Baker and Associates
& _ Ik_F,L' ?
Engineering and Energy
Baker and Associates Fax Transmittal Letter
A DMWW of,Wd aal B*src«po/ada?
Baker and Associates
200 CentrePort Drive, Suite 225
Greensboro, NC 27409
[phone] OUR TELEFAX NO. IS: [phone]
d
Date: 10 N6 1D:> 110 `•
To: , (Company) lpri7lD ?LLl -rr J 6 Vj
(Attention)
Receiving Telecopler No:
From:
?t
4001/003
IF YOU DO NOT RECEIVE THE NUMBER OF PAGES INDICATED, PLEASE
CONTACT OUR OFFICE AS SOON AS POSSIBLE.
..... L1 AKEFtTOA),LATEWFAXTPANS.DOC •.-- Y:. _.,_........ .. ... ... . .
TOTAL NUMBER OF PAGES 3 (INCLUDING THIS TRANSMITTAL PAGE)
10/30/2003 THU 11:45 FAI 336 931 1501 Baker and Associates 1002/003
Oct-30. 2003 11:42AM PIEDMONT TRIAD AIR DEVELOPMENT No-H47 P. 1
WETLAND-type DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wetland-type detention basin system is defined as the wetland-type detention basin, pretreatment
Including energy dissipators and flow spreaders.
Maintenance activities shall be performed as follows:
1. After every significant runoff producing rainfall event and at least monthly:
a. Inspect the detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition.
b. Check and clear the orfice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, rem as necessary to maintain good vegetative cover, mow
vegetative cover on side slopes, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, rlprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the detention basin system semi-annually or when depth is reduced
to 75% of the original design depth. Removed sediment shall be disposed of in an appropriate manner
and shall be handled in a manner that will not adversely impact water quality (i.e. stockpiling near a
detention basin or stream, etc.)_
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
Natural and restored wetlands will be inspected every six months. Corrective action will be taken for any
areas of erosion or concentrated flow. Heavy equipment will be used for these repairs only when so
approved by NCDENR and USACE. During project construction, and until the site Is release by the DI-R,
the natural wetlands, constructed wetlands, and wetland buffers will be inspected every quarter for signs
of erosion and sediment accumulation. Repairs to eroded areas and removal of accumulated sediment
shall be conducted as needed.
When basins are maintained, basin bottoms will be returned to the grades shown on the ss-built plans.
The disturbed surface will be ripped if compacted, and re..vegetated. As necessary, the top 0.3 feet of the
basin bottom will be stockpiled and re-applied to the disturbed area to achieve final grade, or the
disturbed area shall be re-vegetated according to the vegetation planting plan.
5. If the basin must be drained for an emergency or to perfoan maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
6. All components of the detention basin system shall be maintained in good working order.
7. Flow spreaders that provide diffuse flow shall be maintained every six months. All accumulated sediment
and debris shall be removed from the structure, and a level elevation shall be maintained across the
entire flow spreading structure. Any down gradient erosion must be repaired and/or replanted as
necessary.
Pop l of 2
10/30/2003 THU 11:45 FAI 336 931 1501 Baker and Associates 4003/003
00-30, 2003 11:42AM PIEDMONT TRIAD AIR DEVELOPMENT No-0347 P. 2
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.
j?Ie ati
Print name:
Title' Krfi it. V'"CE& 19
Address: 15r YA V 090 o
A I.
!, 1 (E a Notary Public for the State of 1
County of eta 1 do heby certify that
personally appeared befor'a me this . ?day of , and acknowledge the due
execution of the forgoing wetland-type detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
1
My commission expires 0 -
Page 2 of 2
OCT-31-2003 17:43 CHARLOTTE ENGINEERING DEP P•01
cwtfofte- k*knbwy
M
STOR
1 -V
Ppi S!'IVIGt'S
Fax
To: ? CA S+- Q
90 - 733-
From: ^ 'L
`Date: 16 3r'/ 473
lu? Phone: 9 / t
V- 1 7-
?p Total # of pages:
11,wco. 5,?C- "p # Ate /e?
rgent Rari*w []Please COMMeftf []Please Reply []please Regd&
Comment:
City of Charlotte
Enoneering & Property Management
600 E_ f=ourth Street, Charlotte, NC 28202-2844
704-336-2291 telephone
704-336-6586 fox
rr
OCT-31-2003 17:43
S"RN
NAM
s
October 31, 2003
CHARLOTTE ENGINEERING DEP
NC Division of 'Dater Quality
401 Wetlands Certification Unit
Attn: Todd St. John
2321 Crabtree Blvd.
Raleigh, NC 27604
Subject: Comment on the September 30, 2003 Request for Comments on joint state and
federal stream mitigation guidelines
Dear Mr. St. John;
P.02
Thank you for repeating the opportunity to review and comment on the draft joint state and Federal
stream mitigation guidelines (Guidelines). As indicated in your September 30, 2003 Memo, the
Guidelines are intended to provide uniform guidance among the US Army Corps of Engineers,
DWQ, EPA, and NC Wildlife Resources Commission with respect to stream mitigation
requirements. The following comments on the draft Guidelines are provided on behalf of the City of
Charlotte Storm Water Services (CSWS), Charlotte, North Carolina.
CSW S commends the agencies, commitment to collaborating on this effort and producing a
document that is cohesive and usable. We can appreciate the effort that has gone into developing
this document and offer our comments, suggestions, and edits for constructive use. In general our
comments are focused on clarifying whether information in the guidance is presented as
requirements versus recommendations and making the document more reader-friendly (e.g,,
numbering/lettering of sections and sequence of information in Section 11, Monitoring). Our
comments are as follows:
Table of Contents:
Editorial: Update page numbers in Table of Contents to match document.
"Appendices"_
• Consider adding the Macroinvertebrate Monitoring Protocol as an Appendix.
• Include the following forms in the list under Appendix V
o Monitoring Data Record
o Site Selection Determination Form (Under Development)
o Suggested Reference Channel Data Sheet (Under Development)
"1. Introduction°':
• At the end of the last sentence of first paragraph, consider adding the language DWQ
included in the September 30, 2003 Memo to read "...and supersedes DWQ's stream
mitigation guidelines in the .interim, Internal Stream Mitigation and Macroinvertebrate
Monitoring Policy, previously adopted on May 10, 2000_"
To report drainage problems. 336-RAIN Printed on recycled papar.
OCT-31-2003 1?:43 CHARLOTTE ENGINEERING DEP
October 31, 2003 Coxunent Letter
Yhaft Stream Mitigation Guidelines
P.03
Page 2 of 2
• CSW S recommends that the document be modified to allow more project specific flexibility.
Attempting to standardize the requirements by categorizing all projects may restrict
innovative approaches to restoration practices in urban areas. Mitigation requirements (e.g.,
siting, design, monitoring) may need to be proj ect specific in some cases such as the Edwards
Branch Watershed Improvemexit Project_ The guidance should focus on recommended
characteristics to monitor and include the preferred standard or method, to use in performing
the monitoring. The emphasis should be on standardizing what specific parameters are
monitored and how data should be collected for typical projects that fall within each of the
proposed categories. Paragraph 3 and 4 of the Introduction should be modified to clarify that
the agencies are providing recommendations and that for certain projects a modified
approach may be more appropriate.
• Information in this section has been very helpful to CSW S as we are trying to standardize our
monitoring protocols and consultant scope of services for our mitigation projects. Additional
resources on recommended methodologies for performing the various categories of
monitoring would also be beneficial to the regulated community.
• The guidance is not very specific in relation to plant survival monitoring. Are there any
recommendations for monitoring of plant survival for typical stream restoration projects? Is
there a standard total percentage of the site area/stream length that should be surveyed
through the plots? Should the plots be selected randomly each year or just randomly during
an as-built survey and revisited for subsequent years?
• To simplify the presentation of the infornnation and help facilitate quick reference to specific
categories, CSWS offers several hand written suggestions for this section as shown on the
attachment to this comment letter. See attached.
"A endix V Monitorin Data Record",
• CSWS recommends adding a data field in Section 2, Plant Survival for sterns/acre and
percent survival so that a quick reference to success criteria can be made.
Thank you again for the opportunity to review and comment on the draft Guidelines. Again, if you
have any questions concerning our comments or would like further detail, please don't hesitate to
contact me at 704-336-45$$ or mkmurray [e-mail]_nc.us.
Sincerely,
?r
7Ma C.1VI ay
Charlotte Storm Water Services
Attachment
CC' S_ McLendon, US Army Corps of Engineers
OCT-31-2003 17:44 CHARLOTTE ENGINEERING DEP
xxf 1ItTt(TKl0fJ W%0E?1JV5
Reference: NCDENR Stormwater BMP Manual, April 1999
2000 Maryland Stormwater Design Manual Volumes I & B
B. Other Approaches
Other actions that result in demonstrable stream improvements may also be
eligible for stream mitigation crediting on a case-by-case basis. However, these measures
(BMP's or any other activity) must not be a requirement of a NPDES permit or other
regulatory requirement. These options would have to be beyond those measures required
by regulations and should be part of a local watershed restoration plan. These other
options can provide long-term protection for a stream segment or a watershed and
therefore have a role in stream mitigation. However, the US Army Corps of Engineers
and the NC Division of Water Quality may limit the use of these other options in the
context of stream mitigation since these agencies need to ensure that aquatic life uses are
being replaced. These options must receive case-by-case approval from the US Army
Corps of Engineers and the NC Division of Water Quality and must include a provision
for monitoring that will demonstrate the water quality and aquatic life benefits of the
project. As such, projects that target waters with impaired water quality such as 303(d)
waters, closed SA waters and Nutrient Sensitive Waters are more likely to be approved.
11. MONITORING
The purpose of monitoring is to determine the degree of success a mitigation
project has achieved in meeting the objectives of providing proper channel function and
increased habitat quality. Specific objectives trust be included in a project design and
may also be evaluated. In general, monitoring data should provide the District and DWQ
with evidence that the goals of the project were met. Monitoring should be directed at
evaluating primary activities accomplished through mitigation projects. Monitoring
secondary benefits or accomplishments may also be appropriate for large-scale projects,
when projects are done in ecologically important areas or when secondary benefits are a
primary objective. Secondary benefits are those that are not directly accomplished or
established during site construction. For example: a primary activity would be
constructing a root wad revetment, the secondary benefit would be the enhancement of
OVA aquatic populations' three levels of monitoring will be required based on the complexity
roposed. It'` ? AcAA- "y" av?n 'L'am
p
of the mitigation p;-,, ect being
3
1? -to-
C. Upon complet?on o e project, an as-built channel survey sha conduct it
is recommended that stream surveys, for both project construction and project
monitoring, follow the methodology contained in the USDA Forest Service Manual,
Stream Channel Reference Sites (Harrelson, et.al, 1990. The survey should document
the dimension, pattern and profile of the restored channel. Permanent cross-sections
should be established at an approximate frequency of one per 20 (bankfull-width)
lengths. In general, the locations should be selected to represent approximately 50%
pools and 50% riffle areas. Flexibility in the location and frequency will be allowed for
22
P.04
?jogf
P, ' 1t'p- Ma boe
pool 'Ps
?0
OCT-31-2003 17:44 CHARLOTTE ENGINEERING DEP
different levels of mitigation wou require different eve s of monitorin
P.05
cross-sections and should be based on best professional judgment. The selection of
locations should always include areas that may be predisposed for potential problems. In
the case of very narrow streams, two cross-sections per 1,0001f will generally be,
sufficient. The as-built survey should also include photo documentation at all cross-
sections and structures, a plan view diagram, a longitudinal profile, vegetation
information and a pebble count for at least six cross-sections (or all cross sections if less
than six required for project). If the restored stream section is less than 3,000 If, the
longitudinal profile should include the entire 3,000 If, if the stream section is greater than
3,000 If, the profile should be conducted for either 30 % of the restored stream or 3,0001f
(whichever is greater). Subsequent annual surveys will be required Per instructions on 317-
d the monitorin forms (biannual for photo documentation). t should be noted that
escribe the specific_re uirements for the
0-4
Q6'MCI?.?e
C. A3
X Monitvrirrg woos rain
j, Monitoring Level )(:'this level of monitoring willfp Iy to Restoration and Enhancement
Level I projects. Because these projects involve the greatest degree of complexity they
will require a more complex monitoring protocol. The required monitoring shall be
performed each year for the 5-year monitoring period and no less than two bankfull flow
events must be documented through the monitoring period. If less than two bankfull
events occur during the first 5 years, monitoring will continue until the second bankfull
event is documented. The bankfull events must occur during separate monitoring years.
In the event that the required bankfuli events do not occur during the five-year
monitoring period, the Corps and DWQ, in consultation with the resource agencies, may
determine that further monitoring is not required. It is suggested that all bankfull
occurrences be monitored and reported through the required monitoring period.
Monitoring data collected at ipvei I sites should include the following: reference photos,
Apr. plant survival analysis, channel stability analysis, and biological data if specifically
Bi to ical samplin evaluates second im acts of

?iat1?'S Cse?,,)
required?iy permit con ikons ?o g
restoration rojects. D pans o eva uate $0 projects across the state to determine the
nerits of these data in a mitigation monitoring protocol (see "Interim, Internal
'technical Guide Summary - Benthic IVlacroinvertebrate Monitoring Protocols For
Compensatory Stream Restoration Projects, dated July 2002, Version l.3) which is
available on DW 's website h ://h 2aenr.state.nc.us/newetlands/.
W40r**=Tr10i.- Pic th"6 WARM . Biological data may be
required for ethff projects on a case-by-case basi . D e to be collected prior to
construction and for at least 3 years following C01116ucW. A I-year
recolonization/population adjustment time of biological monitoring following
construction is usually warranted. In addition, the yearly data should be collected during
the sam onVhoto documentation will be required twice a year - summer and
winter. eviations from the required monitoring protocol will generally not be
acceptable. However, proposed exceptions will be evaluated on a case-by-case basis by
the District and DWQ, and will be coordinated with appropriate permit review agencies-
,2'L
f1i
Yto
?. 1'llcr?ni o? plank- &AfV1Y4L( ivr fkt riptirun edyvidDY (burger and bd-At" d '1ACIUAesi
I.. M6 feffew2*
sung?{ 6F 5u" 4 pp 1ot,5) lc c- Counts a.r?d '1ec.. coa?+n -
?¢x c?b?11y Vat se.lecl?ed rond6VAto Co. wwoe.Year-abyea(?) and. r<eptes?? -°? d?
'61te. tma. car %Tean "th?).
met
OCT-31-2003 17:44 CHARLOTTE ENGINEERING DEP
J C"-_4 J? I.cu•i s tr 1u.)J11. 1J LAM" tv i-3
j . Monitoring Level 2: This level of monitoring will apply to Enhancement Leve12
projects. Because these projects will generally be on a smaller scale and less complex a
simpler protocol is required. Monitoring data at these sites should include the following:
reference photos and plant survival. Channel stability should also be evaluated when the
mitigation project alters the bankfull channel. Additional types of information may be
required from mitigating parties if recommended and justified by project reviewers. Data
must be collected each year for 5 years at the same time of year. No less than two
bankfulI flow events must be documented through the required 5-year monitoring period.
If less than two bankfull events occur during the first 5 years, monitoring will continue
until the second bankfull event is documented- The bankfull events must occur during
separate monitoring years. It is suggested that all bankfull occurrences be monitored and
reported through the required monitoring period. Deviations from this protocol may be
acceptable when they can be justified.
Monitoring Level 3: This level of monitoring will apply to mitigation consisting only of
preservation. Since the only action in this case is administrative, protecting a reach, a 5-
year monitoring plan is not required. However, reference photos should be taken and
provided to the District and DWQ. These should well document the reach, including the
riparian zone being preserved. As for all photo reference sites, a detailed description of
the location at which the photo was taken should also be provided. Additional types of
information may be required from mitigating parties if recommended and justified by
project reviewers. re cDmow&
prof
f' .Success Criteria: As described above, this guidance r?uee forms of monitoring
to evaluate the success of the project; photo documen ion, ecological function, and
channel stability measurements. These criteria will be used to evaluate success by
considering the following:
Photo documentation
Channel aggradation or degradation
Bank erosion
Success of riparian vegetation
Effectiveness of erosion control measures
Presence or absence of developing instream bars (should be absent)
P.06
Ecolo ical Function
Health and survival of vegetation (80% survival of planted species required after 5 years) ' AI'??
bt 1(1 restoration reach should mimic upstream conditions (or reference reach when applicable) W00U1N1??1C1.
.04
6f l or- 54e
Channel Stability I? f ?
Should be insignificant change from the as-built dimension arO Ix
/!?
Do changes represent a movement in the direction of instability (e.g. increased width to
weA
depth ratio or a decreased width to depth ratio with decreased entrenchment ratio) or are _5(A[W
changes minor and represent an increase in stability (e.g. decreased width to depth ratio IF n qd d
without a decrease in entrenchment ratio)? to &5CU5196"
Should be little change from the as-built longitudinal profile CiAdfr
ryw. U(Id S.
24
OCT-31-2003 17:44 CHARLOTTE ENGINEERING DEP
Pool/riffle spacing should remain fairly constant
pools should not be filling in (aegradation) or riffles starting to change to pools
(degradation)
Pebble count should show a change in the size of bed material toward a desired
composition.
Annual monitoring forms require as-built plans and current data. Monitoring reports
should contain a discussion of any deviations from as-built and an evaluation of the
significance of -these deviations and whether they are indicative of a stabilizing or
destabilizing situation. Appendix H summarizes the measures of success, failure, and
required remedial actions.
P.07
t
- IWE frame.
Specific biological success criteria are currently a subject of applied research being
coordinated by the NC Division of Water Quality. Formal development and adoption of
biological success criteria (if any) will be done upon completion of that research.
25
re?,?r+crmend?
(u mos. 'Fym
VCA- 7)
TOTAL P.07
Re: [Fwd: (no subject)]
Subject: Re: [Fwd: (no subject)]
From: "Kevin Baker" <kjbaker@ mbakercorp.com>
Date: Wed, 29 Oct 2003 14:36:45 -0500
To: <[e-mail]>
I'll be here. Give a yell w/any questions.
tx
"Todd St. John" <[e-mail]> 10/29/2003 2:34:58 PM
got the fax... i've got to leave the office this pm... if the
package
gets in i'll take a look at it first thing tomorrow...
todd
Kevin Baker wrote:
Todd - Check your fax.
course the revised plan
Original
of
the package and Drawing
this
afternoon. It's on the
kevin
We're sending the all the info (except, of
sheet) via fax for you to review.
will arrive in standard FedEx delivery
fax as I'm typing.
"Todd St. John" <[e-mail]> 10/29/2003 10:43:45
AM
as far as lifes little ironies go... fed ex hasn't come by yet, so
I'm
told...
todd
Kevin Baker wrote:
Todd:
Have adjusted per your comments. All the information is in a
FedEx
1 of 8 10/30/03 7:54 AM
Re: [Fwd: (no subject)]
box
on it's way to you. Please call me in the am if you have any
questions,
or don't receive the package.
Thanks for your help!
Kevin
"Todd St. John" <[e-mail]> 10/27/2003 2:24:53
PM
Sorry, Kevin...
-------- Original Message --------
Subject: (no subject)
Date: Mon, 27 Oct 2003 14:22:34 -0500
From: Todd St. John <[e-mail]>
Organization: NC DENR DWQ
To: [e-mail], [e-mail]
CC: john.dorney <[e-mail]>, Cyndi Karoly
<[e-mail]>
Per our meeting today:
I decided to email as oppose to fax. I would like to recommend
the
following additions/modifications to your DRAFT letter that you
provided
at today's meeting:
1) I think it will be more accurate to describe these devices as
flow
2 of 8 10/30/03 7:54 AM
Re: [Fwd: (no subject)]
spreaders since they will not function like level spreaders as
described
in our Design Guidance. In other words the purpose of these
devices
will
be to disperse stormwater into the wetlands so that it will cover
a
certain area of the wetlands as opposed to achieving diffuse
flow,
for
instance. Also, please add the comment that we discussed that
additional
level spreader length may be provided if USACE approval is
obtained
to
impact the wetland buffer.
3) I think we should specifically add some parameters for grading
the
basin bottoms to encourage hydrophytic vegetation. For instance,
I
would
suggest something like: The of the bottom of the basin shall be
graded
and then ripped in such a way to encourage vegetation growth and
that
shall result in approximately 50% of the basin bottom having
small
depressions of no more than 20 feet by 20 feet and that average
0.3
3 of 8 10/30/03 7:54 AM
Re: [Fwd: (no subject)]
to
0.5 feet below the grade shown in the plans. Additionally, small
pools
at least 3 feet deep and at least 10 feet by 10 feet in size
shall
be
spaced at no more than 100 foot centers to provide refugia for
species
such as Gambousia [sp?] for mosquito control. Except for the
baffles
and
inlet and outlet structures, the remaining basin bottom should be
at
or
below the grade shown in the plans. I would suggest that the
second
sentence read something like: Top soil will be stockpiled during
construction and and spread along the bottom of the basins to
establish
the final grade to encourage vegetation growth. Also, I would
recommend
that you provide a planting plan for the bottom of the basins
that
4 of 8 10/30/03 7:54 AM
Re: [Fwd: (no subject)]
will
include the use of a herbaceous wetland seeding mix that will be
recommended by MACTEC and that small, native wetland shrubs of at
least
two species will be planted across approximately 20% of basin
floor
at
a
density of 3 to 5 foot centers. The goal of this planting plan
will
be
to provide hydrophytic vegetation that will also discourage geese
and
other large birds from visiting the basins. Finally, I recommend
that
you provide as built plans to show that the above has been
achieved
once
the basins are converted to permanent stormwater management
devices.
4) "As" should be changed to "If".
5) Please describe why the side slopes are proposed at 2:1.
6) We need some sort of provision in the restored wetlands that
would
5 of 8 10/30/03 7:54 AM
Re: [Fwd: (no subject)]
require repairs that would preclude the formation of any channels
and
maintain disperse flow of stormwater. That aspect could be worked
into
the restoration plan but should be addressed in the Operation and
Maintenance Agreement.
The Operation and Maintenance Agreement (O&M) should address the
fact
that the dry basin will function like a wetland and that the
natural
and
restored wetlands need to be maintained. I recommend that you
review
the
O&M at http://h2o.ehnr.state.nc.us/ncwetlands/oandm.doc.
Additionally, the O&M needs to address the following topics:
1) The natural and restored wetlands need to be inspected every
six
months. If any areas of erosion or concentrated flow are noted,
measures
must be immediately taken to repair eroded areas and to disperse
concentrated flow. None of these repair or maintenance
activities
shall
be conducted with heavy equipment without written authorization
from
DWQ
and the USACE. Also, during the project construction phase and
until
the
6 of 8 10/30/03 7:54 AM
Re: [Fwd: (no subject)]
site is released by DLR the natural wetlands, constructed
wetlands
(once
they are built) and wetland buffers shall be inspected every
quarter
at
a minimum for signs of erosion or sediment accumulation. Repairs
to
eroded areas and removal of significant accumulated sediment
shall
be
conducted as needed without the use of heavy equipment (unless
its
use
is authorized in writing by the USACE and DWQ).
2) I recommend that the term level spreader be changed to flow
spreader.
3) When the basins are maintained. The basin bottoms should be
returned
to the grade as shown in the as built plans. Also, the disturbed
surface
must be ripped if compacted and re-vegetated. The following
methods
of
re-vegetation may be used. The top 0.3 feet of the basin bottom
may
be
stockpiled and reapplied to the disturbed area to achieve final
7 of 8 10/30/03 7:54 AM
Re: [Fwd: (no subject)]
grade.
Or the disturbed area shall be revegetated according to the
vegetation
planting plan above.
8 of 8 10/30/03 7:54 AM
10/30/2003 THU 14:10 FAX [phone] Baker and Associates
m,a-m
Engineering and Energy
Baker and Associates Fax `transmittal Le er
a Don oraehaaearkrcareaeto?
Baker and Associates
200 CenhvParf Drive, Suite 225
Greensboro, NC 27409
[phone] OUR TELEFAX NO. IS. [phone]
Date: I C) 156 In
To: (Cc
(At
Receiving
From:
MESSAGE:

IF YOU DO NOT RECEIVE THE NUMBER OF PAGES INDICATED, PLEASE
CONTACT OUR OFFICE AS SOON AS POSSIBLE. . .

X1001/002
Lie TEMPLATESYFAXTRMSJWC
TOTAL. NUMBER OF PACES L (INCLUDING THIS TRANSMITTAL PAGE)
10/30/2003 THU 14;10 FAY 336 931 1501 Baker and Associates
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40
SEE SHEET SG17 FOR H
<,• J r• t1 .:'??'?..,?' : . • AND VERTICAL LOCATIC
ENERGY DISSIPATER TABLE
• SEE MCDOT STD, DRAWING #838.27
O SEE NCDOT STD. DRAWING #838.01
WA = NO DISSIPATER REQUIRED
- I
PIEDMONT TRIAD INTERNATION
MIMED -PCL _ PIEPInONT TRIAD AIRPORT AWHORITY GkLEHSk
DAAWN woJ M I
SAILER AND ASSQCIA,
CNEGI?a MICER AND ASSOMTES
-25470
$O ?CEfTR NM ItII?SUITI 225 GBEENSI

CONSULTING ENGINEERS
(336)M41SOO FAM(3361"1-1Sa'I
T. - 1 ?:i
OF WATER
?O? QG
Michael F. Easley
Governor
William G. Ross, Jr., Secretary
Department of Environment and Natural Resources
Alan W. Klimek, P.E., Director
Division of Water Quality
October 30, 2003
Mr. Mickie Elmore
Director of Development
Piedmont Triad Airport Authority
P.O. Box 35445
Greensboro, NC, 27425
Subject: Piedmont Triad Airport Authority
Modified Dry Pond/Wetlands
DWQ Project No. 000846
Guilford County
Dear Mr. Elmore:
This Office is in receipt of the plans dated August 20, 2003 with the modifications to the basin baffles
received October 29, 2003, the flow spreaders dated October 29, 2003, and for the plan narrative and
Operation and Maintenance Agreement dated October 30, 2003 for the three modified dry detention/wetland
basins followed by flow spreading devices that will discharge into natural and restored wetlands for the "Fed Ex"
portion of the subject facility prepared on your behalf by Baker and Associates and submitted to the Division on
October 30, 2003. Staff from the Wetlands Unit reviewed the plans and found them acceptable for the purpose
of meeting the requirements of Condition no. 8a of Certification no. 3428 (only). Please note that this approval
is for water quality purposes only and shall not be construed as an approval of the design for dam/outlet
structure integrity, Dam Safety, public safety, or flood attenuation purposes.
If you have any questions regarding this matter, please contact Mr. Todd St. John at [phone].
Sincerely,
`
Jo R. Dorney
Wetlands Unit Supervisor
cc: Winston-Salem Regional Office
USACE Raleigh Regional Office
Todd St. John
File
North Carolina Division of Water Quality, 401 Wetlands Certification Unit,
1650 Mail Service Center, Raleigh, NC 27699-1650 (Mailing Address)
2321 Crabtree Blvd., Raleigh, NC 27604-2260 (Location)
919-733-1786 (phone), 919-733-6893 (fax), http://h2o.enr.state.nc.us/ncwetiands/
WATfi
`OHO A?,G Michael F. Easley
Governor
r William G. Ross, Jr., Secretary
5 _q Department of Environment and Natural Resources
n T Alan W. Klimek, P.E., Director
Division of Water Quality
October 30, 2003
Mr. Mickie Elmore
Director of Development
Piedmont Triad Airport Authority
P.O. Box 35445
Greensboro, NC, 27425
Subject: Piedmont Triad Airport Authority
Modified Dry Pond/Wetlands
DWQ Project No. 000846
Guilford County
Dear Mr. Elmore:
This Office is in receipt of the plans dated August 20, 2003 with the modifications to the basin baffles
received October 29, 2003, the flow spreaders dated October 29, 2003, and for the plan narrative and
Operation and Maintenance Agreement dated October 30, 2003 for the three modified dry detention/wetland
basins followed by flow spreading devices that will discharge into natural and restored wetlands for the "FedEx"
portion of the subject facility prepared on your behalf by Baker and Associates and submitted to the Division on
October 30, 2003. Staff from the Wetlands Unit reviewed the plans and found them acceptable for the purpose
of meeting the requirements of Condition no. 8a of Certification no. 3428 (only). Please note that this approval
is for water quality purposes only and shall not be construed as an approval of the design for dam/outlet
structure integrity, Dam Safety, public safety, or flood attenuation purposes.
If you have any questions regarding this matter, please contact Mr. Todd St. John at [phone].
Si cerely,
Jo R. Dorney
Wetlands Unit Supervisor
cc: Winston-Salem Regional Office
USACE Raleigh Regional Office
Todd St. John
File
North Carolina Division of Water Quality, 401 Wetlands Certification Unit,
1650 Mail Service Center, Raleigh, NC 27699-1650 (Mailing Address)
2321 Crabtree Blvd., Raleigh, NC 27604-2260 (Location)
919-733-1786 (phone), 919-733-6893 (fax), http://h2o.enr.state.nc.us/ncwetlands/
Re: Fwd: PTIA seed mix?
Subject: Re: Fwd: PTIA seed mix?
From: "Kevin Baker" <[e-mail]>
Date: Thu, 30 Oct 2003 13:55:28 -0500
To: <todd. st. j ohn @ ncmail. net>
My understanding is that we are to treat each baffle that way. The
detail we sent you will be standard to all ponds/all baffels, unless
you
direct otherwise.
Would you like to see it done differently for each pond?
"Todd St. John" <[e-mail]> 10/30/2003 1:44:01 PM
Kevin, is there going to be a low point in the baffle SG111SG10
also?
In
other words, does that typical apply to both F3 and F2 in about the
same
place?
Kevin Baker wrote:
Todd:
Karisa Sandiford in our office said that she thinks the fax number
may
have changed? Is the number I gave you below correct? She's
going
to
try it again at that number, and at another number she thinks may
be
the
new one. She is also scanning the document and will e-mail it.
If
none
of the electron-oriented methods work, call me and I'll drive it
over.
tx
Kevin
"Todd St. John" <[e-mail]> 10/30/2003 12:23:09
PM
1 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
i do not have the fax... it is not in the machine...
Kevin Baker wrote:
Todd:
Just faxed (to 919/733-9959) revised, signed & notarized 0&M
agreement.
Let me know if you don't receive it.
tx
Kevin
"Todd St. John" <todd.st.johnCncmail.net> 10/30/2003 9:48:33
AM
Yes... i think that would be fine...
Kevin Baker wrote:
Can we deal with this one by saying that we will seed it with a
mix
that
is approved by DENR at the time?
2 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
"Todd St. John" <[e-mail]> 10/30/2003
9:24:21 AM
the seed mix sounds like a food plot for deer... some of the
species
may
do ok in wetlands,
se...
todd
Kevin Baker wrote:
but it does not sound like a wetland mix per
Wetlands was the direction Richard provided. Do you want to
see
something different?
"Todd St. John" <[e-mail]> 10/30/2003
9:10:55 AM
3 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
is that proposed seed mix for wetlands or uplands?
Kevin Baker wrote:
Todd:
MACTEC's suggested plantings. See number 8 for my reason on
the
10-15
foot centers.
tx
Kevin
"Leatherland, Ben" <[e-mail]>
4 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
10/27/2003
4:14:02
spoke
look
PM
Kevin,
Richard Darling asked me to send you potential seed mix
recommendations
for detention basins at PTIA. He mentioned that one of the
main
issues
would be to discourage waterfowl from using these basins. I
with
the N.C. Wildlife Resources Commission (NCWRC), and also
took a
5 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
spp.) .
at
the N.C Erosion and Sediment Control Planning and Design
Manual.
Here
are some suggestions:
1) Use native herbaceous species. Avoid using low
grasses
(e.g.,
fescue), as these may attract geese.
2) Avoid using deep-rooting species along dams or
berms.
3) Avoid planting Phragmites spp. or cat-tails (Typha
4) Consider letting the detention basin 'naturalize'
over
time,
6 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
dam
and only periodically remove the largest vegetation.
5) Consider strip mowing along the dam (i.e., mow 1/3
of
face
each year, and rotate which 1/3 is mowed annually).
6) NCWRC recommends considering the following species,
in a
seed
mix applied at 7 lbs/acre (we've seen similar mixes applied
at 15
lbs/acre):
20% - Switchgrass (Panicum virgatum)
20% - Panicgrass (Panicum dichotomiflorum)
20% - Deertongue (Panicum clandestinum)
10% - Orchard grass (Dactylic glomerata)
10% - Alfalfa (Medicago sativa).
10% - Ladino clover (Trifolium repens)
10% - Wheat (Triticum aestivum) in fall/winter
7) Also apply a temporary cover crop of annual rye
(Secale
cereale) in the autumn, winter, or spring (at 120 lbs/acre),
or
7 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
apply
a
temporary cover crop of German millet (Setaria italica) in
summer
(at
40
lbs/acre).
8) Consider seeding or planting (at 10-15 ft
on-center) the
following woody species also:
Serviceberry (Amelanchier spp.)
Persimmon (Diospyros virginiana)
Black haw (Viburnum prunifolium)
Sumac (Rhus coppallina)
Black willow (Salix nigra)
Please call with any questions. I hope these general
suggestions
help.
Ben Leatherland, P.W.S., CPESC
MACTEC Engineering and Consulting, Inc.
8 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
the
2801 Yorkmont Road, Suite 100
Charlotte, NC 28208
704.357.5610 (direct)
704.357.8638 (fax)
[e-mail]
www.mactec.com
MACTEC Engineering and Consulting, Inc. (MACTEC) reserves
all
copyright
rights, but grants a temporary license to the recipient to
use
materials contained in the attached computer data file for
use in
development of recipient's work associated with this
project.
MACTEC
said
and
if
does not warrant the accuracy of any information contained
in
data
file. MACTEC assumes no liability for unauthorized
alterations
alterations to the information contained herein.
This e-mail is confidential and legally privileged
information.
9 of 11 10/30/03 1:58 PM
Re: Fwd: PTIA seed mix?
you
are not the intended recipient kindly inform the sender
immediately
and
destroy the original and all
distribution,
disclosure, or the taking of
copies. Any copying,
any action in reliance on the
contents
of
this e-mail, or part thereof, in any form whatsoever,
without the
sender's express written consent, is prohibited and may be
unlawful.
10 of 11 10/30/03 1:58 PM
Engineering and Energy
Baker and Associates Fax Transmittal Letter
A Dhlskn ofMiehad Baker Corporation
Baker and Associates
200 CentrePort Drive, Suite 225
Greensboro, NC 27409
[phone] OUR TELEFAX NO. IS: [phone]
a
Date: 10 /Ab tTo: (Cc
(At
Receiving
From:
MESSAGE:
IF YOU DO NOT RECEIVE THE NUMBER OF PAGES INDICATED, PLEASE
CONTACT OUR OFFICE AS SOON AS POSSIBLE.
L.WKER TEMPLATESTAXTRANSAOC .. .. J. -.ti::.. _ _ .
TOTAL NUMBER OF PAGES 2- (INCLUDING THIS TRANSMITTAL PAGE)
0('- - lk - F,
Baker and Associates
200 CentrePort Drive, Suite 225
Greensboro, NC 27409
[phone] OUR TELEFAX NO. IS: [phone] / lwl 0j }m
Date: 1() (36 16 -)"),
To: (Company) IUD 4 ? d
(Attention) f.i1 - C" 6L
Receiving Telecopier No:
From:i Ct 13 8a?7
TOTAL NUMBER OF PAGES 3 (INCLUDING THIS TRANSMITTAL PAGE)p? d23'Z
MESSAGE:

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IF YOU DO NOT RECEIVE THE NUMBER OF PAGES INDICATED, PLEASE
CONTACT OUR OFFICE AS SOON AS POSSIBLE.
... '. L:18AKER 7EMPLATESTAXTRANS.DOC . - , ....:. , : • - -
Oct-30. 2003 11:42AM PIEDMONT TRIAD AIR DEVELOPMENT No-0347 P. 1
WETLAND-type DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wetland-type detention basin system is defined as the wetland-type detention basin, pretreatment
including energy dissipators and flow spreaders.
Maintenance activities shall be performed as follows:
1. After every significant runoff producing rainfall event and at least monthly:
a. Inspect the detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, re-seed as necessary to maintain good vegetative cover, mow
vegetative cover on side slopes, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the detention basin system semi-annually or when depth is reduced
to 75% of the original design depth. Removed sediment shall be disposed of in an appropriate manner
and shall be handled in a manner that will not adversely impact water quality (i.e. stockpiling near a
detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
Natural and restored wetlands will be inspected every six months. Corrective action will be taken for any
areas of erosion or concentrated flow. Heavy equipment will be used for these repairs only when so
approved by NCDENR and USAGE. During project construction, and until the site is release by the DLR,
the natural wetlands, constructed wetlands, and wetland buffers will be inspected every quarter for signs
of erosion and sediment accumulation. Repairs to eroded areas and removal of accumulated sediment
shall be conducted as needed.
When basins are maintained, basin bottoms will be returned to the grades shown on the as-built plans.
The disturbed surface will be ripped if compacted, and re-vegetated. As necessary, the top 0.3 feet of the
basin bottom will be stockpiled and re-applied to the disturbed area to achieve final grade, or the
disturbed area shall be re-vegetated according to the vegetation planting plan.
5. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
6. All components of the detention basin system shall be maintained in good working order.
7. Flow spreaders that provide diffuse flow shall be maintained every six months. All accumulated sediment
and debris shall be removed from the structure, and a level elevation shall be maintained across the
entire flow spreading structure. Any down gradient erosion must be repaired and/or replanted as
necessary.
Pala l of 2
Oct-30. 2003 11:42AM PIEDMONT TRIAD AIR DEVELOPMENT No.0341 P. 2
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.
Printname:
Title:
Address: 64 15 YAN jI &V 6--fte9S 0 0
Phc
Sig
Dal
pp a Notary Public for the State of i i ru,
Coun of &-a 1 , do her9by certify that
personally appeared before me this ? 5J day of ,,71LY 3, and acknowledge the due
execution of the forgoing wetland-type detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
My commission expires o ^
Page 2 of 2
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PIEDMONT TRIAD INTERNATION
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CHECKED ARB
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OCT-29-2003 WED 02:28 PH ENV SCIENCES BRANCH FAX NO, 919 733 9959
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October 30, 2003
Mr. Todd St. John
North Carolina Department of Environmental and Natural Resources
Division of Water Quality - Wetlands Unit
2321 Crabtree Boulevard
Raleigh, NC 27604-2260
Subject: FedEx Development Program
Stormwater Management Review
Dear Mr. St. John:
Per your request, we are providing additional information for the subject effort. We have
enclosed the following:
¦ Drawing depicting the stormwater ponds, associated water quality BMP's, and the
surrounding natural terrain
¦ Signed/notarized maintenance agreement for the proposed ponds
¦ Surface Area Drainage Area (SADA) calculations for each system
¦ Detail of Baffle tie-ins
¦ Revised detail (typical section) of flow spreaders
The proposed system is a modification of the standard BMP manual, as it includes the use of
natural and restored wetlands, as well as a modified dry pond that will function like a non-marsh
wetland. The proposed system is meant to function like an extended detention wetland. It
includes similar design features, such as a 2-5 day detention of the runoff from a 1-inch rain. It
provides more surface area than would be required for an extended detension wetland, without
the marsh-type characteristics that could endanger aircraft.
As we have discussed, during construction, these ponds will function in an E&S role. They will
only truly begin to function as stormwater management ponds upon completion of the proposed
FedEx development, which is scheduled to occur in the 2008-2009 timeframe. In response to
specific issues discussed, we offer the following solutions for the final stormwater management
plan:
l.) Flow Spreaders have been reconfigured per-our discussion. These will be further
lengthened in the field, if such modification is approved by USACE.
2.) Pond F2 Emergency Spillway has been relocated per our discussion.
3.) The bottom of the pond will be graded per your suggestion, with small recesses to
form ephemeral ponds. The area will be graded, ripped and topsoiled with stockpiled
material to encourage vegetative growth. Specifically, per your suggestion, we
propose that approximately 50% of the basin will have small depressions not larger
than 20' x 20', and average depth of 3-6 inches. Additional small pools not larger
than 10' x 10' and average depth of 3 feet will be provide on approximately 100 foot
centers to encourage mosquito control species. The entire basin floor of the ponds
will be planted with herbaceous and shrubby vegetation as approved by DWQ.
Approximately 20% of the basin floors will be planted with shrubby wet tolerant
vegetation to discourage unwanted wildlife on 3-5 foot centers depending on plant
size. MACTEC has provided a suggested planting list that is included with this
submittal.
4.) If permitted by the USAGE, logs will be placed near the toe of the embankments, and
in the natural wetlands to assist with dispersion of higher flows.
5.) Sides of the ponds incorporate 2:1 slopes as recommended by FAA to deter wildlife.
The. system will use a combination of dry ponds modified per item three, level spreaders, natural
buffer area, and natural wetlands to achieve water quality standards. The attached SADA
calculations are based upon DENR criteria for Extended Detention Wetlands, and show that more
than adequate area is available.
Please feel free to call me at 336/931-1500 with any questions.
Sincerely,
BAKER AND ASSOCIATES
Kevin J. Baker, P.E.
Assistant Vice President
Enclosures
cc: Cindi Karoli, DWQ (w/o Enclosure)
M. L. Elmore, PTAA (w/o Enclosure)
10/30/2003 THU 13:52 FAI 336 931 1501 Baker and Associates

It! w
Engineering and Energy
Baker and Associates
A O1r sftd of Miohad Baklr CmrMr wn
Baker and Assodatas
200 CentrePart Drive, Suite 225
Fax Transmittal Leger
Greensboro, NC 27409 1
(336) 9a1-1500 OUR TELEFAX NO. IS: [phone] J CA IS PO
1
Date: I?ic1 ?}J Q!
To: (Company) lU J b' IJ
(Attention) -?
Receiving Tetecopier No:
From:
Z001/003
TOTAL NUMBER OF PAGES (INCLUDING THIS TRANSMITTAL PAGE) 108 -- d z3
IF YOU DO NOT RECEIVE THE NUMBER OF PAGES INDICATED, PLEASE
CONTACT OUR OFFICE AS SOON AS POSSIBLE.
L1 MrM,
10/30/2003 THU 13:52 FA,I 336 931 1501 Baker and Associates ? 002/003
Oct.30. 2003 11.42AM PIEDMONT TRIAD AIR DEVELOPMENT No.0347 P. 1
WETLAND-type DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wetland-type detention basin system is defined as the wetland-type detention basin, pretreatment
including energy dissipators and flow spreaders-
Maintenance activities shall be performed as follows:
1. After every significant runoff producing rainfall event and at least monthly.
a. Inspect the detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition.
b. Check and clear the orifice of any obstructlons such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, reseed as necessary to maintain good vegetative cover, mow
vegetative cover on side slopes, and remove trash as needed.
3. Inspect and repair the collection system (Le- catch basins, piping, swales, riprap, etc-) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the detention basin system semi-annually or when depth is reduced
to 75% of the original design depth- Removed sediment shall be disposed of in an appropriate manner
and shall be handled In a manner that wig not adversely impact water quality (i.e. stockpiling near a
detention basin or stream, etc.)-
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
Natural and restored wetlands will be inspected every six months. Corrective action will be taken for any
areas of erosion or concentrated flow. Heavy equipment will be used for these repairs only when so
approved by NMENR and USACE. During project construction, and until the site is release by the DLR,
the natural wetlands, constructed wetlands, and wetland buffers will be inspected every quarter for signs
of erosion and sediment accumulation. Repairs to eroded areas and removal of accumulated sediment
shall be conducted as needed.
When basins are maintained, basin bottoms will be returned to the grades shown on the as-built plans.
The disturbed surface will be ripped if compacted, and re-vegetated- As necessary, the top 4.3 fleet of the
basin bottom will be stockpiled and re-applied to the disturbed area to achieve final grade, or the
disturbed area shall be re-vegetated according to the vegetation planting plan.
5. If the basin must be dralned for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
6. All components of the detention basin system shall be maintained in good working order.
7. Flow spreaders that provide diffuse flow shall be maintained every six months. All accumulated sediment
and debris shall be removed from the structure, and a level elevation shall be maintained across the
entire flow spreading structure- Any down gradient erosion must be repaired and/or replanted as
necessary.
Page t oft
10/30/2003 THU 13:53 FAI 336 931 1501 Baker and Associates Z003/003
Oct-30. 2003 11,-L2AM PIEDMONT TRIAD AIR DEVELOPMENT No-OW P. 2
1 acknowledge and agree by my signature below that I am responsible fear the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.
Print narne; G k? P, L 1 a
I, 1 a Notary Public for the State of i
County of t , do heby certify that
,
personally appeared before me this _day of and acknowledge the due
execution of the forgoing wetland-type detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
My commission expires d ^ -
Page 2 of 2
Title. . + t?
Address. 64
(no subject)
Subject: (no subject)
From: "Todd St. John" <[e-mail]>
Date: Mon, 27 Oct 2003 14:22:34 -0500
To: [e-mail], [e-mail]
CC: "john.dorney" <[e-mail]>, Cyndi Karoly
<Cyndi. Karoly @ NCMai1. Net>
Per our meeting today:
I decided to email as oppose to fax. I would like to recommend the
following additions/modifications to your DRAFT letter that you
provided at today's meeting:
1) I think it will be more accurate to describe these devices as
flow spreaders since they will not function like level spreaders as
described in our Design Guidance. In other words the purpose of
these devices will be to disperse stormwater into the wetlands so
that it will cover a certain area of the wetlands as opposed to
achieving diffuse flow, for instance. Also, please add the comment
that we discussed that additional level spreader length may be
provided if USACE approval is obtained to impact the wetland buffer.
3) I think we should specifically add some parameters for grading
the basin bottoms to encourage hydrophytic vegetation. For instance,
I would suggest something like: The of the bottom of the basin shall
be graded and then ripped in such a way to encourage vegetation
growth and that shall result in approximately 500 of the basin
bottom having small depressions of no more than 20 feet by 20 feet
and that average 0.3 to 0.5 feet below the grade shown in the
plans. Additionally, small pools at least 3 feet deep and at least
10 feet by 10 feet in size shall be spaced at no more than 100 foot
centers to provide refugia for species such as Gambousia [sp?] for
mosquito control. Except for the baffles and inlet and outlet
structures, the remaining basin bottom should be at or below the
grade shown in the plans. I would suggest that the second sentence
read something like: Top soil will be stockpiled during construction
and and spread along the bottom of the basins to establish the final
grade to encourage vegetation growth. Also, I would recommend that
you provide a planting plan for the bottom of the basins that will
include the use of a herbaceous wetland seeding mix that will be
recommended by MACTEC and that small, native wetland shrubs of at
least two species will be planted across approximately 200 of basin
floor at a density of 3 to 5 foot centers. The goal of this planting
plan will be to provide hydrophytic vegetation that will also
discourage geese and other large birds from visiting the basins.
Finally, I recommend that you provide as built plans to show that
the above has been achieved once the basins are converted to
permanent stormwater management devices. . 4) "As" should be changed
to "If" .
5) Please describe why the side slopes are proposed at 2:1.
1 of 2 10/27/03 3:02 PM
(no subject)
6) We need some sort of provision in the restored wetlands that
would require repairs that would preclude the formation of any
channels and maintain disperse flow of stormwater. That aspect could
be worked into the restoration plan but should be addressed in the
operation and maintenance Agreement.
The Operation and Maintenance Agreement (0&M) should address the
fact that the dry basin will function like a wetland and that the
natural and restored wetlands need to be maintained. I recommend
that you review the O&M at
http://h2o.ehnr.state.nc.us/ncwetlands/oandm.doc.
Additionally, the O&M needs to address the following topics:
1) The natural and restored wetlands need to be inspected every six
months. If any areas of erosion or concentrated flow are noted,
measures must be immediately taken to repair eroded areas and to
disperse concentrated flow. None of these repair or maintenance
activities shall be conducted with heavy equipment without written
authorization from DWQ and the USACE. Also, during the project
construction phase and until the site is released by DLR the natural
wetlands, constructed wetlands (once they are built) and wetland
buffers shall be inspected every quarter at a minimum for signs of
erosion or sediment accumulation. Repairs to eroded areas and
removal of significant accumulated sediment shall be conducted as
needed without the use of heavy equipment (unless its use is
authorized in writing by the USACE and DWQ).
2) I recommend that the term level spreader be changed to flow
spreader.
3) When the basins are maintained. The basin bottoms should be
returned to the grade as shown in the as built plans. Also, the
disturbed surface must be ripped if compacted and re-vegetated. The
following methods of re-vegetation may be used. The top 0.3 feet of
the basin bottom may be stockpiled and reapplied to the disturbed
area to achieve final grade. Or the disturbed area shall be
revegetated according to the vegetation planting plan above.
2 of 2 10/27/03 3:02 PM
Baker and Associates
A Unit of Michael Baker Corporation
200 CentrePort Drive, Suite 225
Greensboro, NC 27409
[phone]
FAX [phone]
October 28, 2003
Mr. Todd St. John
North Carolina Department of Environmental and Natural Resources
Division of Water Quality - Wetlands Unit
2321 Crabtree Boulevard
Raleigh, NC 27604-2260
Subject: FedEx Development Program
Stormwater Management Review
Dear Mr. St. John:
WETLANDS 1401 GROUP
OCT 2 9 2003
WATER QUALITY SECTION
Per your request, we are providing additional information for the subject effort. We have
enclosed the following:
¦ Drawing depicting the stormwater ponds, associated water quality BMP's, and the
surrounding natural terrain
¦ Signed/notarized maintenance agreement for the proposed ponds
¦ Surface Area Drainage Area (SADA) calculations for each system
¦ Detail of Baffle tie-ins
¦ Revised detail (typical section) of flow spreaders
As we have discussed, during construction, these ponds will function in an E&S role. They will
only truly begin to function as stormwater management ponds upon completion of the proposed
FedEx development, which is scheduled to occur in the 2008-2009 timeframe. In response to
specific issues discussed, we offer the following solutions for the final stormwater management
plan:
1.) Flow Spreaders have been reconfigured per our discussion. These will be further
lengthened in the field, if such modification is approved by USACE.
2.) Pond F2 Emergency Spillway has been relocated per our discussion.
3.) The bottom of the pond will be graded per your suggestion, with small recesses to
form ephemeral ponds. The area will be graded and topsoiled with stockpiled
material to encourage vegetative growth. Specifically, per your suggestion, we
propose that approximately 50% of the basin will have small depressions not larger
than 20' x 20', and average depth of 3-6 inches. Additional small pools not larger
than 10' x 10' and average depth of 3 feet will be provide on approximately 100 foot
centers to encourage mosquito control species. The ponds will be planted with
herbaceous and shrubby vegetation as recommended by Mactec, to a total of
approximately 20% of the basin floors on 10-15 foot centers (as recommended by
MACTEC). MACTEC has provided a list of recommended species, which is
included in the attached e-mail.
4.) If permitted by the USACE, logs will be placed near the toe of the embankments, and
in the natural wetlands to assist with dispersion of higher flows.
5.) Sides of the ponds incorporate 2:1 slopes as recommended by FAA to deter wildlife.
The system will use a combination of dry ponds modified per item three, level spreaders, natural
buffer area, and natural wetlands to achieve water quality standards. The attached SADA
calculations are based upon DENR criteria for Extended Detention Wetlands, and show that more
than adequate area is available.
Please feel free to call me at 336/931-1500 with any questions.
Sincerely,
BAKE AND ASSOCIATES
Kevin J. Baker, P.E.
Assistant Vice President
Enclosures
cc: Cindi Karoli, DWQ (w/o Enclosure)
M. L. Elmore, PTAA (w/o Enclosure)
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WETLAND-type DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wetland-type detention basin system is defined as the wetland-type detention basin, pretreatment
including energy dissipators and flow spreaders.
Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, re-seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the detention basin system semi-annually or when depth is reduced
to 75% of the original design depth (see diagram below). Removed sediment shall be disposed of in an
appropriate manner and shall be handled in a manner that will not adversely impact water quality (i.e.
stockpiling near a detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
Natural and restored wetlands and wetland buffers will be inspected every six months. Corrective action
will be taken for any areas of erosion or concentrated flow. Heavy equipment will be used for these
repairs only when so approved by NCDENR and USACE.
When basins are maintained, basin bottoms will be returned to the grades shown on the as-built plans.
As necessary, the top 0.3 feet of the basin bottom will be stockpiled and re-applied to the disturbed area
to achieve final grade, or the disturbed area shall be revegetated according to the vegetation planting
plan.
5. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
6. All components of the detention basin system shall be maintained in good working order.
7. Flow spreaders that provide diffuse flow shall be maintained every six months. All accumulated sediment
and debris shall be removed from the structure, and a level elevation shall be maintained across the
entire flow spreading structure. Any down gradient erosion must be repaired and/or replanted as
necessary.
Page 1 of 2
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.
Print name: ( t? L ?I mvte a
Title:
Note: The legally responsible party should not be a homeowners association unless more than 50% of the
lots have been sold and a resident of the subdivision has been named the president.
I, , a Notary Public for the State of b County of L 2 , do herby certify that
personally appeared before me this C?M day of clq- 'e. and acknowledge the due
execution of the forgoing wetland-type detention basin maintenance requirements. Witness my hand and
official seal,
SEAL ?t
My commission expires
Page 2 of 2
z74og
Address: &4r lb Kt(A,J 61-VD.
DVA-rr
October 27, 2003
Mr. Todd St. John
North Carolina Department of Environmental and Natural Resources
Division of Water Quality - Wetlands Unit
2321 Crabtree Boulevard
Raleigh, NC 27604-2260
Subject: FedEx Development Program
Stormwater Management Review
Dear Mr. St. John:
Per your request, we are providing additional information for the subject effort. We have
enclosed a drawing depicting the stormwater ponds, associated water quality BMP's, and the
surrounding natural terrain. Also enclosed is a signed/notarized maintenance agreement for the
nproposed ponds, and Surface Area Drainage Area (SARA) calculations for each pond.
94"14n response to specific issues discussed, we offer the following:
1.) Level Spreaders have been reconfigured per our discussion.
2.) Pond F2 Emergency Spillway has been relocated per our discussion. d
3.) The bottom of the pond will be graded per your suggestion, with small recesses to s/T t
(? form ephemeral ponds. The area will be topsoiled to encourage vegetative growth.
?G 4.) j ? permitted by the USACE, logs will be placed near the toe of the embankments, W'
and in the natural wetlands to assist with dispersion of higher flows.
The syste will use a combination of dry ponds modified per item three, level spreaders, natural
buffer area, and natural wetlands to achieve water quality standards. The attached SADA
calculations are based upon DENR criteria for Extended Detention Wetlands, and show that more
than adequate area is available.
Please feel free to call me at 336/931-1500 with any questions.
Sincerely,
BAKER AND ASSOCIATES
G? r

SS?
Kevin J. Baker, P.E.
AV Assistant Vice President f
60,
Enclosures d?
cc: Cindi Karoli, DWQ (w/o Enclosure)
M. L. Elmore, PTAA (w/o Enclosure)
P
15Z Kz2;-
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33b 13/ /FV)
DRY DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The dry detention basin system is defined as the dry detention basin, associated energy dissipators and level
spreaders.
Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the dry detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, re-seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the dry detention basin system semi-annually or when temporary
pool depth is reduced to 75% of the original design depth (see diagram below). Removed sediment shall
be disposed of in an appropriate manner and shall be handled in a manner that will not adversely impact
water quality (i.e. stockpiling near a dry detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
When the elevation of the sediment areas exceed the designed temporary pool elevation, the sediment
should be removed to design levels. The basin will be seeded and mulched again following removal of the
sediment.
`* gl? All components of the dry detention basin system shall be maintained in good working order.
6. Level spreaders or other structures that provide diffuse flow shall be maintained every six months. All
accumulated sediment and debris shall be removed from the structure, and a level elevation shall be
maintained across the entire flow spreading structure. Any down gradient erosion in must be repaired
and/or replanted as necessary.
I acknowledge and agree by my signature below that I am responsible for the performance of the maintenance
procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to
the system or responsible party.
Print name:
Title:
Address:
Phone:
Signature:
Date:
Page 1 of 2
a Notary Public for the State of ,
County of , do hereby certify that
personally appeared before me this day of , and acknowledge the due
execution of the forgoing dry detention basin maintenance requirements. Witness my hand and official seal,
SEAL
My commission expires
Page 2 of 2
OCT-29-2003 WED 02:19 PM ENV SCIENCES BRANCH FAX NO, 919 733 9959
10/29/2003 WED 14;47 FA% 336 931 1501 Baker and Associates
Eno[ ne?King andnwrey
Baker and Associates
ADMdara/AfthW40 C60NOW
Fax Transmittal Letter
Saker and Assn WOS
280 Cemmpott twW, Suite 225
Greensboro, NC 27909
(338) 9,11400 OUR TELEFAX NO. 15. [phone]
a
Date,
To: (Company) --
(AtfenEion} D
ReWvft -foleoopler tdb:
From: 1?0 Y! h T6.1 .et( _. - - -- -- J
TOTAL NUMBER OF PAOEs B. (INCLUmo YW TRAN816TTAL PAGE)
P. 01
gaol/008
IF YOU DO NOT RECEIVE THE NUMBER OF PAGES INDICATED, PLEASE
CONTACT OUR OFFICE AS SOON AS POSSIBLE.
,. ,. .raeaxs?zrwwsaras+rrunwws.ooc ? .. .. ,., ., ., ? ...........:.:? ,•,:.str,, .. ...... ....., , ,??,: ..
OCT-29-2003 WED 02,19 PM ENV SCIENCES BRANCH FAX NO. 919 733 9959
10/29/2003 WED 14.47 FAX [phone] Baker and Associates
Ta
[phone]
FAX [phone]
October 26, 2003
Mr. Todd St. John
North Carolina Department of Environmental and Natural Resources
Division of Watac Quality - Wetlands Unit
232t Crabtree Boulevard
Raleigh, NC 276042260
Subject: FedE.x Development Program
Stormwater Management Review
Dear Mr. 5t. John-.
Per your reques4 we are providing additional infonnadon for the subject effort, We have
enclosed the following:
¦ Drawing depicting the stotmwater ponds, associated water quality BMP's, and the
surrounding natural terrain
• Signedlnotatizcd maintenance agreement for the proposed ponds
¦ Surface Area Drainage Area (SARA) calculations for each systems
¦ Detail of BaM* tie-ins
¦ Revised detail (typical section) of flow spreaders
As we have discussed, during construction, these ponds will function in an US role. 't'hey will
only truly begin to Ammon as stormwater mia ugement ponds upon completion of the proposed
FW& development, which is scheduled to occur in the 2009-2009 timeframc, in response to
specific issues discassad, we offer the following solutions for the final storrawater marmSemert
plan:
1.) Flow Spreaders have been reconfigured. per our discussion. These will be hither
lengthened in the #kki. if such modification is approved by USACE.
2.) Pond F2 Emergency Spillway has been relocated per our discussion.
3.) The bottom of the pond will be graded per your suggestion, with small recesses to
form ephemeral ponds. The area will be graded and top-soiled with stockpiled
material to encourage vegetative growth. Spocifrcally, per your suawtion, we
propose that, approximately 501% of the basin will save small depressions not larger
than 20' x 20', and average depth of 3-6 inches. Additional small pools not larger
than 10'x 10' and avcrage-depth of 3 feet will be provide on approximately 100 foot
centers to encourage mosquito control species. The ponds will be planted with
herbaceous and shrubby vegetation as recommended by Mactec, to a total of
approximately 200% of the basin floors on 10-15 foot centers (as r mommended by
P. 02
1002/00$
OCT-29-2003 WED 02:20 PN ENV SCIENCES BRANCH FAX NO, 919 733 9959 P. 03
10/29/2003 fil)11:48 FAI 336 931 1601 Baker and Associates gQ03/908
IvtACIEC). MACIEC has provided a list of recommended species, which is
included in the attached a-mail.
4.) If permitted by the USACE, logs will be placed new the toe of the embanlonents, and
the natural wetlands to assist with dispersion of higher flows.
5,) Sides of the ponds incorporate 2:1 slopes as recommended by FAA to deter wildlife,
The system will use a combination of dry ponds modified per item throe, level spreaders, natural
buffer area, and natural wetlands to achieve water quality standards. The attached SARA
calculations are based upon DEW criteria for Extendod Detention. Wetlands, and show that more
than adequate area is available.
Please feel free to call me at 336/931-1$00 with any questions.
i
Sincerely,
. BAK t?ND ASSOCIATES
Keviti T. Baker, P.E.
Assistant Vice President
Enclosures
cc: Cindi Karoli DWQ (w/o Enclosure)
M. L. Elmore, PTAA (w/o Enclosure)
OCT-29-2003 WED 02:20 PM ENV SCIENCES BRANCH FAX NO. 919 733 9959 P. 04
10/29/2003 WED 14;48 FAI 336 931 1501 Baker and Associates gm /m

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OCT-29-2003 WED 02:20 PM ENV SCIENCES BRANCH FAX NO. 919 733 9959 P. 05
10/29/2003 14,48 FAX [phone] Baker and Associates A005/008
WETLAND-type DETENTION BASIN OPERATION AND MAINTCNANCE AGREEMENT
The wetland-type detention basin system Is deiined as the wetland-type detention basin, pretreatment
including energy dissipators and flow spreaders.
Maintenance activities shall be performed as follows:
1. After every signfiicant runoff producing rainfall event and at least monthly:
a. inspect the detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition.
b. Check and dear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, re-seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, rlprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the detention basin system seml-annually or when depth Is reduced
to 76% of the original design depth (see diagram below). Removed sediment shall be disposed of in an
appropriate manner and shall be handled in a manner that will not adversely impact water quality (i.e.
stockpiling near a detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
Natural and restored wetlands and wetland buffers wiN be inspected every six months. Corrective action
will be taken for any areas of erosion or concentrated flow. Heavy equipment will be used for these
repairs only when so approved by NCDENR and USACE.
When basins are maintained, basin bottoms will be returned to the grades shown on the as-built plans.
As necessary, the top 0.3 feet of the basin bottom will be stockpiled and reapplied to the disturbed area
to achieve final grade, or the disturbed area shall be revegetated according to the vegetation planting
plan.
5. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
6. All components of the detention basin system shall be maintained in good working order.
7. now spreaders that provide diffuse flow shall be maintained every six months. All accumulated sediment
and debris shall be removed from the structure, and a level elevation shall be maintained across the
entire flow spreading structure. Any down gradient erosion must be repaired and/or replanted as
necessary.
Page t of 2
OCT-29-2003 WED 02:27 PM ENV SCIENCES BRANCH FAX NO. 919 733 9959
10/29/2003 WED 14:48 M 336 931 1501 faker and Associates
P. 01/04
WETLAND-typo DETENTION BASIN OPERATION AND MAJNTENANCE AGREEMENT
The wetland-type detention basin system Is defined as the wetland-type detention basin, pretreatment
including energy dissipators and flow spreaders.
Maintenance activities shall be performed as follows:
1. After every significant nurwff producing rainfall event and at least monthly:
a. Inspect the detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2, Repair eroded areas Immediately, re-seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. inspect and repair the collection system (i.e. catch basins, piping, sweles, dprep, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the detention basin system semi-annually or when depth Is reduced
to 75% of the original design depth (see diagram below). Removed sediment shall be disposed of in an
appropriate manner and shall be handled In a manner that will not adversely impact water quality (i.e.
stockpiling near a detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shalt be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
Natural and restored wetlands and wetland buffers wiN be inspected every six months. Corrective action
will be taken for any areas of erosion or concentrated flow. Heavy equipment will be used for these
repairs only when so approved by NCDENR and tlSACE.
When basins are maintained, basin bottoms will be returned to the grades shown on the as-built plans.
As necessary, the top 0.3 feet of the basin bottom will be stockpiled and re-applied to the disturbed area
to achieve final grade, or the disturbed area shall be revegetated according to the vegetation planting
plan.
5 N the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maxlrnum extent practical.
6. All components of the detention basin system shall be maintained In good working order.
7. Flow spreaders that provide diffuse flaw shall be matntained every six months. All accumulated sediment
and debris shall be removed from the structure, and a level elevation shall be maintained across the
entire flow spreading structure. Any down gradient erosion must be repaired and/or replanted as
necessary.
0
Page 1 of 2
OCT-29-2003 WED 02:27 PM ENV SCIENCES BRANCH FAX NO, 919 733 9959
10/29/2003 WED 14:48 FAI 336 931 1501 Baker and Associates
P. 02/04
@006/008
I acknowledge and agree by my signature below that 1 am responsilAe for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.
Print name: ia 9 L I iLimyfp -------___---
Note; The legally responsible party should not be a homeowners association unless more than 6A'61' the
lots have been soW and a resident of the subdivision has been named the president.
1, a Notary Public jfr the State of
County of OU-i 14" do he y certify/that _
personally appeared before me this day of Ci J(' b?e jjXZ and acknowledge the due
execution of the forgoing wetland-type detention basin maintenance requirements. Witness my hand and
official seal,
SEAL
My commission expires- / "
OCT-29-2003 WED 02:28 PM ENV SCIENCES BRANCH FAX NO. 919 733 9959
10/29/2003 IED 14;48 FAI 336 931 1501 Baker and Associates
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Baker and Associates ?? I r„
200 CentrePort Drive, Suite 225 `fi1 ?'("J
Greensboro, NC 27409
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FED EX stormwater plan
Subject: FED EX stormwater plan
From: "Todd St. John" <[e-mail]>
Date: Fri, 26 Sep 2003 08:45:42 -0400
To: [e-mail]
CC: John.dorney" <[e-mail]>, Cyndi Karoly
<[e-mail]>, "daryl.lamb" <[e-mail]>
Mickie,
(I seem to have lost Kevin's email address, could you please forward
this to him?)
As we discussed yesterday during our meeting, it does not appear
that you will be able to meet the 85% TSS removal requirement for a
WSIII watershed by traditional means. However, the Wetalnds Unit
does believe that a combination of created or designed wetlands the
will discharge via flow dispersing devices into natural and restored
wetlands can achieve the above requirement. I have made this
determination based on the extent of the existing natural wetlands
and by suggesting revisions to the existing plans as we discussed
yesterday. The following is a summary of the necessary revisions to
the plan:
1) The length, width, design and location of the flow spreading
devices and the emergency spillway must be modified as we discussed
and hand-drew on the plans. The width of the flow spreading devices
must also be maximized. If the USACE agrees, the lip must be
constructed of hard material such as block, concrete, or other
materials to achieve precise, even flow. If not the lip must be
precisely graded, compacted and stabilized to provide even flow.
2) The bottoms of the detention basins must be graded and ripped to
encourage small ephemeral pond areas thereby creating a constructed
wetland. We can discuss exact grading parameters later. We would
also want to apply 4" to 8" inches of top soil (if available) to
encourage vegetation growth.
3) As we discussed, we would like to explore the use of hand-placed
natural materials such as logs, etc. generated by the site
construction to help maintain and maximize dispersed flow into and
in the wetlands (pending USACE agreement).
4) The Operation and Maintenance Agreement will also have to be
crafted to reflect the need to conduct hand repairs and maintenance
in the existing, natural wetlands as well as normal maintenance of
the basins and flow dispersion devices.
5) There were other items that we discussed that we all agreed would
be provided.
1 of 2 9/26/03 9:03 AM
FED EX stonnwater plan
This email is not the formal approval of your stormwater plan for
the FED Ex phase, but is intended to provide confirmation of what we
discussed. I discussed these concepts with John and Cyndi and we are
willing to accept the concepts if they can be achieved.
Thanks, todd
2 of 2 9/26/03 9:03 AM
Sunset Beach - 2003
April 2003
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Subject ?.ev?/ eaC?e-, Ty?vica,l gyros -.Iwbon
Page No. of
The Business of Airports
www.mbakercorp.com
Michael F. Easley
Governor
William G. Ross, Jr., Secretary
Department of Environment and Natural Resources
Alan W. Klimek, P.E., Director
Division of Water Quality
September 19, 2003
Mr. Kevin Baker, PE
Baker and Associates
200 Centre Port Drive, Suite 225
Greensboro, NC 27409
Subject:
Dear Mr. Baker:
FedEx Development Program
DWQ Project No. 000846
Guilford County
The Wetlands Unit staff reviewed the stormwater management plans for the subject project and determined that additional
information is necessary to complete the technical review process. The required additional information is as follows:
Site Plans
2.
3.
4.
5.
6.
7
Please provide a set of full sized site plans that includes all of the detail requested below.
Temporary Water Quality Pool
You indicated that the runoff from the one inch rain will be used to size the temporary water quality related volume
to be stored and release over a 4 day period. Please provide that volume for each pond. Also, please provide a
worksheet for each dry detention basin available at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.html.
Conditions 8, 9, 10, and 11 of the 401 Water Quality Certification
Please review conditions 8, 9, 10 and 11 of the 401 Water Quality Certification no. 3428. Each of these conditions
has interrelated aspects that must be integrated with the current proposed stormwater management plan. It is
recommended that a meeting be set up to discuss these issues and how the conditions can be met. I thought we
had a meeting scheduled for September 17, 2003, but apparently it was not confirmed.
Draw Down Orifice Outlet
Please provide additional detail regarding the orifice installed directly through the end cap. Please provide
protection of the outlet from debris.
Forebays
It is not clear from the plans provided for ponds F2 and F3 will prevent short circuiting or provide a 3:1 flow path.
Please reconfigure the berms to lengthen the flow path.
Vegetated Side Slopes
The basin side slopes above the permanent pool down to the vegetative shelf should be stabilized with vegetation
and side slopes no steeper than 3:1 (horizontal to vertical). The bottom of the basins should also be vegetated. We
had previously discussed the types of vegetation that may be acceptable in regards to FAA safety guidelines.
Level Spreaders
Level spreaders must be designed according to the Level Spreader Design Options available at
http://h2o.ehnr.state.nc.us/ncwetlands/level.pdf with the intent to provide a forested filter strip as described in the
North Carolina Division of Water Quality, 401 Wetlands Certification Unit,
1650 Mail Service Center, Raleigh, NC 27699-1650 (Mailing Address)
2321 Crabtree Blvd., Raleigh, NC 27604-2260 (Location)
919-733-1786 (phone), 919-733-6893 (fax), http://h2o.enr.state.nc.us/ncwetlands/
Page 2 of 2
NC DENR Stormwater Best Management Practices Manual. It is not clear that the level spreaders have actually
been designed or provided (The plan detail is very small and I cannot clearly see the contours). It is essential the
level spreaders be precisely level as well as able to withstand the flows that enter them and those that overflow the
lip. The proposed lengths appear to be inadequate based on the 10 year discharge entering them. It is
recommended that the discharge from the orifice that draws down the captured runoff from the 1" rain be isolated
and sent to the level spreader. In any event, the discharge from the level spreader as well as the receiving
(infiltration) area down to the nearest stream or other feature that would tend to intercept the flow and concentrate it
must be independent from that of larger discharges. Additionally, the larger discharges cannot be released at a
velocity that would be erosive to the receiving area, buffer or wetland. In this case, the discharges that will be
entering the level spreader. The presumed level spreaders provided also appear to be discharging onto very steep
slopes. This issue must also be addressed. It will also be necessary to provide an adequate site plan to show the
distance of flow and existing topography down to any intercepting feature that will tend to concentrate the flow. Also,
it is not clear from the plans provided what the fate of the flows from the level spreaders will be. The level spreaders
must be located in the most optimal location to provide the greatest amount of flow diffusion and infiltration,
particularly into the existing wetlands. It is my anticipation that the proposed ponds.and outlets will have to be
reconfigured to meet these criteria.
Please provide a typical detail for the level spreaders. The typical plans must show appropriate materials for and
design of the lip and that adequate flow dissipation will be provided to prevent the flow from discharging in a
concentrated manner (or jumping) at any point along the spreading device. The proposed dissipaters may be
adequate to slow the discharge but it is not clear whether or not the discharge would jump over the level spreader at
the discharge point during larger discharge events.
Please fill out a worksheet for each level spreader used. These are available at
hftp://h2o.ehnr.state.nc.us/ncwetiands/mitresto.html.
8. Drainage Area
Stormwater BMPs must be designed to treat all of the runoff draining to the basin. Please provide the site plans
including the collection system draining to each basin. Also, the purpose and function of the junction chamber
(SG10, JC1) is not clear. Please provide and explanation.
9. Worksheets
Please provide a worksheet for each dry detention basin and level spreader available at
hftp://h2o.ehnr.state.nc.us/ncwetiands/mitresto.html.
10. Operation and Maintenance Agreement
An operation and maintenance agreement is required. An example operation and maintenance plan can be found
at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.html. The operation and maintenance agreement must also be
signed by the responsible party and notarized.
If you have any questions or would like to discuss this project, please contact me at [phone]. Also, please note
that the NC DENR Stormwater Best Management Practices Manual as well as other documents and information can be
downloaded from the Wetlands Unit web site at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.htmi.
Sincerely,
v
Todd St. John, PE
Environmental Engineer
cc: Winston-Salem Regional Office
Cyndi Karoly
File

t/q A N
QG
Michael F. Easley
Governor
William G. Ross, Jr., Secretary
Department of Environment and Natural Resources
Alan W. Klimek, P.E., Director
Division of Water Quality
September 19, 2003
Mr. Kevin Baker, PE
Baker and Associates
200 Centre Port Drive, Suite 225
Greensboro, NC 27409
Subject: FedEx Development Program
DWQ Project No. 000846
Guilford County
Dear Mr. Baker:
The Wetlands Unit staff reviewed the stormwater management plans for the subject project and determined that additional
information is necessary to complete the technical review process. The required additional information is as follows:
1. Site Plans
Please provide a set of full sized site plans that includes all of the detail requested below.
2. Temporary Water Quality Pool
You indicated that the runoff from the one inch rain will be used to size the temporary water quality related volume
to be stored and release over a 4 day period. Please provide that volume for each pond. Also, please provide a
worksheet for each dry detention basin available at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.html.
3. Conditions 8, 9, 10, and 11 of the 401 Water Quality Certification
Please review conditions 8, 9, 10 and 11 of the 401 Water Quality Certification no. 3428. Each of these conditions
has interrelated aspects that must be integrated with the current proposed stormwater management plan. It is
recommended that a meeting be set up to discuss these issues and how the conditions can be met. I thought we
had a meeting scheduled for September 17, 2003, but apparently it was not confirmed.
4. Draw Down Orifice Outlet
Please provide additional detail regarding the orifice installed directly through the end cap. Please provide
protection of the outlet from debris.
5. Forebays
It is not clear from the plans provided for ponds F2 and F3 will prevent short circuiting or provide a 3:1 flow path.
Please reconfigure the berms to lengthen the flow path.
6. Vegetated Side Slopes
The basin side slopes above the permanent pool down to the vegetative shelf should be stabilized with vegetation
and side slopes no steeper than 3:1 (horizontal to vertical). The bottom of the basins should also be vegetated. We
had previously discussed the types of vegetation that may be acceptable in regards to FAA safety guidelines.
7. Level Spreaders
Level spreaders must be designed according to the Level Spreader Design Options available at
http://h2o.ehnr.state.nc.us/ncwetlands/level.pdf with the intent to provide a forested filter strip as described in the
North Carolina Division of Water. Quality, 401 Wetlands Certification Unit,
1650 Mail Service Center, Raleigh, NC 27699-1650 (Mailing Address)
2321 Crabtree Blvd., Raleigh, NC 27604-2260 (Location)
919-733-1786 (phone), 919-733-6893 (fax), http://h2o.enr.state.nc.us/ncwetlands/
Page 2 of 2
NC DENR Stormwater Best Management Practices Manual. It is not clear that the level spreaders have actually
been designed or provided (The plan detail is very small and I cannot clearly see the contours). It is essential the
level spreaders be precisely level as well as able to withstand the flows that enter them and those that overflow the
lip. The proposed lengths appear to be inadequate based on the 10 year discharge entering them. It is
recommended that the discharge from the orifice that draws down the captured runoff from the 1" rain be isolated
and sent to the level spreader. In any event, the discharge from the level spreader as well as the receiving
(infiltration) area down to the nearest stream or other feature that would tend to intercept the flow and concentrate it
must be independent from that of larger discharges. Additionally, the larger discharges cannot be released at a
velocity that would be erosive to the receiving area, buffer or wetland. In this case, the discharges that will be
entering the level spreader. The presumed level spreaders provided also appear to be discharging onto very steep
slopes. This issue must also be addressed. It will also be necessary to provide an adequate site plan to show the
distance of flow and existing topography down to any intercepting feature that will tend to concentrate the flow. Also,
it is not clear from the plans provided what the fate of the flows from the level spreaders will be. The level spreaders
must be located in the most optimal location to provide the greatest amount of flow diffusion and infiltration,
particularly into the existing wetlands. It is my anticipation that the proposed ponds.and outlets will have to be
reconfigured to meet these criteria.
Please provide a typical detail for the level spreaders. The typical plans must show appropriate materials for and
design of the lip and that adequate flow dissipation will be provided to prevent the flow from discharging in a
concentrated manner (or jumping) at any point along the spreading device. The proposed dissipaters may be
adequate to slow the discharge but it is not clear whether or not the discharge would jump over the level spreader at
the discharge point during larger discharge events.
Please fill out a worksheet for each level spreader used. These are available at
hftp://h2o.ehnr.state.nc.us/ncwetiands/mitresto.htmi.
8. Drainage Area
Stormwater BMPs must be designed to treat all of the runoff draining to the basin. Please provide the site plans
including the collection system draining to each basin. Also, the purpose and function of the junction chamber
(SG10, JC1) is not clear. Please provide and explanation.
9. Worksheets
Please provide a worksheet for each dry detention basin and level spreader available at
hftp://h2o.ehnr.state.nc.us/ncwetlands/mitresto.htmi.
10. Operation and Maintenance Agreement
An operation and maintenance agreement is required. An example operation and maintenance plan can be found
at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.htmi. The operation and maintenance agreement must also be
signed by the responsible party and notarized.
If you have any questions or would like to discuss this project, please contact me at [phone]. Also, please note
that the NC DENR Stormwater Best Management Practices Manual as well as other documents and information can be
downloaded from the Wetlands Unit web site at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.htmi.
Sincerely,
Todd St. John, PE
Environmental Engineer
cc: Winston-Salem Regional Office
Cyndi Karoly
File
WAT
pG
September 19, 2003
Mr. Kevin Baker, PE
Baker and Associates
200 Centre Port Drive, Suite 225
Greensboro, NC 27409
Subject:
Dear Mr. Baker:
Michael F. Easley
Governor
William G. Ross, Jr., Secretary
Department of Environment and Natural Resources
Alan W. Klimek, P.E., Director
Division of Water Quality
FedEx Development Program
DWQ Project No. 000846
Guilford County
The Wetlands Unit staff reviewed the stormwater management plans for the subject project and determined that additional
information is necessary to complete the technical review process. The required additional information is as follows:
Site Plans
Please provide a set of full sized site plans that includes all of the detail requested below.
2. Temporary Water Quality Pool
You indicated that the runoff from the one inch rain will be used to size the temporary water quality related volume
to be stored and release over a 4 day period. Please provide that volume for each pond. Also, please provide a
worksheet for each dry detention basin available at http://h2o.ehnr.state.ne.us/ncwetlands/mitresto.htnil.
3.
4.
5.
6.
7.
Conditions 8, 9, 10, and 11 of the 401 Water Quality Certification
Please review conditions 8, 9, 10 and 11 of the 401 Water Quality Certification no. 3428. Each of these conditions
has interrelated aspects that must be integrated with the current proposed stormwater management plan. It is
recommended that a meeting be set up to discuss these issues and how the conditions can be met. I thought we
had a meeting scheduled for September 17, 2003, but apparently it was not confirmed.
Draw Down Orifice Outlet
Please provide additional detail regarding the orifice installed directly through the end cap. Please provide
protection of the outlet from debris.
Forebays
It is not clear from the plans provided for ponds F2 and F3 will prevent short circuiting or provide a 3:1 flow path.
Please reconfigure the berms to lengthen the flow path.
Vegetated Side Slopes
The basin side slopes above the permanent pool down to the vegetative shelf should be stabilized with vegetation
and side slopes no steeper than 3:1 (horizontal to vertical). The bottom of the basins should also be vegetated. We
had previously discussed the types of vegetation that may be acceptable in regards to FAA safety guidelines.
Level Spreaders
Level spreaders must be designed according to the Level Spreader Design Options available at
http://h2o.ehnr.state.nc.us/ncwetlands/level.pdf with the intent to provide a forested filter strip as described in the
North Carolina Division of Water. Quality, 401 Wetlands Certification Unit,
1650 Mail Service Center, Raleigh, NC 27699-1650 (Mailing Address)
2321 Crabtree Blvd., Raleigh, NC 27604-2260 (Location)
919-733-1786 (phone), 919-733-6893 (fax), http://h2o.enr.state.nc.us/ncwetlands/
Page 2of2
NC DENR Stormwater Best Management Practices Manual. It is not clear that the level spreaders have actually
been designed or provided (The plan detail is very small and I cannot clearly see the contours). It is essential the
level spreaders be precisely level as well as able to withstand the flows that enter them and those that overflow the
lip. The proposed lengths appear to be inadequate based on the 10 year discharge entering them. It is
recommended that the discharge from the orifice that draws down the captured runoff from the 1" rain be isolated
and sent to the level spreader. In any event, the discharge from the level spreader as well as the receiving
(infiltration) area down to the nearest stream or other feature that would tend to intercept the flow and concentrate it
must be independent from that of larger discharges. Additionally, the larger discharges cannot be released at a
velocity that would be erosive to the receiving area, buffer or wetland. In this case, the discharges that will be
entering the level spreader. The presumed level spreaders provided also appear to be discharging onto very steep
slopes. This issue must also be addressed. It will also be necessary to provide an adequate site plan to show the
distance of flow and existing topography down to any intercepting feature that will tend to concentrate the flow. Also,
it is not clear from the plans provided what the fate of the flows from the level spreaders will be. The level spreaders
must be located in the most optimal location to provide the greatest amount of flow diffusion and infiltration,
particularly into the existing wetlands. It is my anticipation that the proposed ponds.and outlets will have to be
reconfigured to meet these criteria.
Please provide a typical detail for the level spreaders. The typical plans must show appropriate materials for and
design of the lip and that adequate flow dissipation will be provided to prevent the flow from discharging in a
concentrated manner (or jumping) at any point along the spreading device. The proposed dissipaters may be
adequate to slow the discharge but it is not clear whether or not the discharge would jump over the level spreader at
the discharge point during larger discharge events.
Please fill out a worksheet for each level spreader used. These are available at
http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.htmI.
8. Drainage Area
Stormwater BMPs must be designed to treat all of the runoff draining to the basin. Please provide the site plans
including the collection system draining to each basin. Also, the purpose and function of the junction chamber
(SG10, JC1) is not clear. Please provide and explanation.
9. Worksheets
Please provide a worksheet for each dry detention basin and level spreader available at
http://h2o.ehnr.state.nc.usincwetlands/mitresto.html.
10. Operation and Maintenance Agreement
An operation and maintenance agreement is required. Ad example operation and maintenance plan can be found
at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.html. The operation and maintenance agreement must also be
signed by the responsible party and notarized.
If you have any questions or would like to discuss this project, please contact me at [phone]. Also, please note
that the NC DENR Stormwater Best Management Practices Manual as well as other documents and information can be
downloaded from the Wetlands Unit web site at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.html.
Sincerely,
Todd St. John, PE
Environmental Engineer
cc: Winston-Salem Regional Office
Cyndi Karoly
File
W AT F9
II??QG
Michael F. Easley
Governor
William G. Ross, Jr., Secretary
Department of Environment and Natural Resources
Alan W. Klimek, P.E., Director
Division of Water Quality
February 21, 2003
Mr. Alan R. Berenbrok, P.E.
Baker and Associates
200 CenterPort Drive, Suite 225
Greensboro, NC 27409
Subject: Dry Basins F1, F2 and F3
PTAA
DWQ Project No.
Guilford County
Dear Mr. Berenbrok:
The Wetlands Unit staff reviewed the stormwater management plans for the subject ponds that are part of this project. In
order to receive final approval for these ponds further information would be necessary. The additional information is as
follows:
. Temporary Water Quality Pool
It is presumed that the temporary water quality pool volume has changed from previous submittals. It will be
necessary to provide the calculations and volume to be stored.
. Dry Basin Location
It is not clear where the dry basins are to be located at the facilities.
. Inlet/Outlet Structure Location
The inlet and outlet structures of F2 and F3 must be placed to minimize short circuiting and turbulence. A long flow
path will help to maximize the settling efficiency of the water quality structure. You had previously indicated that a
flow path of 3:1 would be provided. This may be achieved by configuring the forebay berms to create a longer flow
path, for instance. A
. Level Spreaders
Level spreaders should be designed according to the Level Spreader Design Options available at
http://h2o.ehnr.state.nc.us/ncwetlands/level.pdf. The level spreader length must be sized to accommodate the
maximum release rate as opposed to the maximum release rate from the 1" rain draw down orifice, unless the only
discharge to the level spreader is from the 1" rain draw down orifice. The latter does not appear to be the case in
this situation. It maybe necessary to reconfigure the discharge outlets and/or emergency spill ways so that all of the
discharges beyond that of the 1" rain draw down orifice bypass the level spreader/filter strip system.
Y¥. Remainder of the Stormwater Management Plan
As you mentioned in your correspondence, there have been several additions and revisions to the stormwater
management plan for this project over an extended period of time. As such, it is no longer clear which aspects of
the plans and revisions that have been submitted are still applicable. As such, I recommend that a summary of the
current stormwater management plan, as it relates to the application for 401 Water Quality Certification, be
completely and at one time, resubmitted. The submittal should contain the specific BMPs proposed, the specific
drainage areas tributary to the specific BMPs, the amount or percentage of anticipated impervious area in each
North Carolina Division of Water Quality, 401 Wetlands Certification Unit,
1650 Mail Service Center, Raleigh, NC 27699-1650 (Mailing Address)
2321 Crabtree Blvd., Raleigh, NC 27604-2260 (Location)
919-733-1786 (phone), 919-733-6893 (fax), http://h2o.enr.state.nc.u6/ncwetlands/
Page 2 of 2
drainage area, and other BMP sizing information used in your calculations. The submittal should also include the
pertinent design information for each BMP, such as temporary storage volumes, surfaces areas, swale lengths, etc.
Also, specific references to previously submitted detailed aspects of the plans should be provided, if applicable.
Please note that it is important that adequate areas and site locations be provided that will allow for the construction
of BMPs that will meet the DWQ design criteria for 85% TSS removal for each drainage area.
I understand that you may have provided most or all of this information previously. However, as stated above due to
the extended period of time and number of various submittals and revisions, I am no longer certain which aspects of
the plan are correct. As such, to avoid any potential delays in a decision in regards to the 401 Water Quality
Certification application. I recommend providing a summary each time any part of the stormwater management plan
is revised and submitted to this Office. This will help clarify which revisions are current.
. Worksheets
Worksheets for dry basins, stormwater ponds, wetlands, grassed swales, level spreaders and bioretention areas
can be found at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.htmi. Also, an example operation and maintenance
agreement can be found at http://h2o.ehnr.state.nc.us/ncwetlands/mitresto.html.
If you have any questions or would like to discuss this project, please contact me at [phone]. Also, please note
that the NC DENR Stormwater Best Management Practices Manual as well as other documents and information can be
downloaded from the Wetlands Unit web site at http://h2o.ehnr.state.ne.us/ncwetlands/mitresto.htmi.
Sincerely,
Todd St. John, PE
Environmental Engineer
cc: Winston-Salem Regional Office
File
STATE OF
NORTH CAROLINA
DEPARTMENT OF n`
ENVIRONMENT, HEALTH
.NATURAL RESOURCES
L
DIVISION OF
WATER QUALITY
Administrative Code Section:
15A NCAC 2H.0500
Water Quality Certification
Amended Effective: October 1, 1996
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EHNR - ENVIRONMENTAL MANAGEMENT T15A: 02H .0500
SECTION .0500 - WATER QUALITY CERTIFICATION

.0501 PURPOSE
(a) The provisions of this Section shall apply to all division regulatory, planning, resource management, liaison
and financial aid determinations that affect surface waters and wetlands as defined by 15A NCAC 2B .0202. This
Section shall only apply to specific activities which require state review after the effective date of this Rule and
which require a Division determination concerning effects on surface waters or wetlands. Activities that are
described in Section 404(f)(1)(A)-M of the Clean Water Act (33 U.S.C. 1344) are exempt from this Rule.
(b) These Rules outline the application and review procedures for activities that require water quality
certifications (certifications) pursuant to Section 401 of the Clean Water Act (33 U.S.C. 1341). Certifications are
required whenever construction or operation of facilities will result in a discharge into navigable waters as described
in 33 CFR Part 323. The federal definition of navigable waters includes wetlands as defined at 33 CFR 328.3 and'
40 CFR 230.3.
(c) Certifications may be issued for individual activities (individual certifications) or issued for specific types or
groups of activities (general certifications):
(1) Individual certifications are issued on a case-by-case basis and the procedures outlined in the following
Rules are required for each individual certification.
(2) General certifications are issued for specific types or groups of activities that are similar in nature and
considered to have minimal impact. The application and review procedures for requesting concurrence
from the Division that the general certification can be used for the proposed activity are the same as the
procedures outlined in the following Rules for individual certifications unless specifically stated otherwise
in the general certification.
History Note: Authority G.S. 143-215.3(a)(1), 143-215.3(c); 143B-282(1)(u),
RRC Objection Eff. July 18, 1996 due to lack of statutory authority and ambiguity,
Eff. October 1, 1996.
.0502 APPLICATION
(a) Application for Certification. Any person, as defined in Article 21, Chapter 143, North Carolina General
Statutes, desiring issuance of the state certification or coverage under a general certification required by Section 401
of the Federal Water Pollution Control Act as amended shall file with the Director of the North Carolina Division
of Water Quality (director), at the office in Raleigh, North Carolina, an original and six copies of an application
for certification. Submission of an application to the Division of Coastal Management for permits to develop in
North Carolina's coastal area shall suffice as an application for certification. The application shall specify:
(1) the date of application;
(2) the name, address, and phone number of the property owner;
(3) if the applicant is a corporation, the state in which it is domesticated, the name of its principal officers,
the name and address of the North Carolina process agency, and the name of the individual who shall be
primarily responsible for the conduct of the activity for which certification is sought;
(4) the nature of the activity to be conducted by applicant;
(5) whether the discharge has occurred or is proposed;
(6) the location of the discharge, stating the municipality, if applicable; the county; the drainage basin; the
name of the receiving waters; and the location of the point of discharge with regard to the receiving
waters;
(7) a description of the receiving waters, including type (creek, river, swamp, canal, lake, pond or estuary)
if applicable; nature (fresh, brackish or salt); and wetland classification;
(8) description of the type of waste treatment facilities if applicable.
(b) Maps. There shall be attached to the application a map(s) or sketch(es) of sufficient detail to accurately
delineate the boundaries of the lands owned or to be utilized by the applicant in carrying out its activity; the
location, dimensions and type of any structures erected or to be erected on said lands for use in connection with the
activity; and the location and extent of the receiving waters including wetlands within the boundaries of said lands.
(c) Power to Request Additional Information. The Director may request, and the applicant shall furnish, any
additional information that may be found necessary for the proper consideration of the application.
(d) Omissions From Applications. If the applicant considers that it is not feasible or is unnecessary to furnish
any portion of the information required by Paragraphs (a) and (b) of this Rule, applicant shall submit a detailed
NORTH CAROLINA ADMINISTRATIVE CODE 10115196 Page 1
EHNR - ENVIRONMENTAL MANAGEMENT TISA: 02H.0500
statement explaining the reasons for omission of any such information.
(e) Investigations. The staff of the Department of Environment, Health, and Natural Resources (department)
shall conduct such investigation as the Director deems necessary; and applicant shall cooperate in the investigation
to the extent that it shall furnish necessary information, allow the staff safe access to the lands and facilities of the
applicant and lend such assistance as shall be reasonable.
(f) Who Must Sign Applications. The application shall be considered a "valid application" only if the application
bears the signature of a responsible officer of the company, municipal official, partner or owner. This signature
certifies that the applicant has title to the property, has been authorized by the owner to apply for certification or
is a public entity and has the power of eminent domain. Said official in signing the application shall also certify
that all information contained therein or in support thereof is true and correct to the best of his knowledge.
(g) An application form may be obtained from the Division of Water Quality, the Division of Coastal
Management, or the U.S. Army Corps of Engineers, Wilmington District, Regulatory Branch.
History Note: Authority G.S. 143-215.3(a)(1); 143-215(c), 143B-282(1)(u);
E„ f `: February 1, 1976,
Amended Eff. December 1, 1984; January 1, 1979;
RRC Objection Eff. July 18, 1996 due to lack of statutory authority and ambiguity;
Recodifted from 15A NCAC 2H. 0501 E„ . October 1, 1996;
Amended Eff. October 1, 1996.
.0503 PUBLIC NOTICE
(a) Notice by Publication. Notice of each pending application for an individual certification shall be published
one time in a newspaper having general circulation in the county in which the discharge will occur, or as provided
in Paragraph (c) of this Rule. Publication shall be made at least 15 days prior to proposed final action by the
Director upon the application and not more than 20 days after acceptance of a completed application.
(b) Contents of Notice. The notice shall set forth the name and address of the applicant; the action requested
in the application; the nature and location of the discharge; and the proposed date of final action to be taken by the
Director upon the application. The notice shall also state that additional information is on file with the department
and may be inspected at any time during normal working hours. Copies of such information on file shall be made
available upon request and upon payment of the cost thereof to the department.
(c) The public notice requirement may also be satisfied by a joint notice with the Division of Coastal
Management (15A NCAC 7J .0206) or the U.S. Army Corps of Engineers according to their established procedures.
(d) Notice of Hearing. If the Director determines that a hearing should be held concerning the granting or denial
of the application, the Director shall publish notice of the hearing one time in a newspaper having general circulation
in the county in which the discharge will occur. The notice shall be published at least 30 days prior to the date of
the hearing. The notice shall state the time, place and nature of the hearing.
(e) Water Quality Certification Mailing List. Any person, may request that he or she be mailed copies of all
public notices required by this Rule. The Director shall add the name of any such person to a water quality
certification mailing list and shall mail copies of notices to all persons on the list.
(f) Payment of Costs of Public Notice. The applicant shall pay to, the department the costs of advertising public
notice required by Paragraphs (a) and (d) of this Rule. Certification shall be withheld until such costs have been
paid.
History Note. Authority G .S. 143-215.3(a)(1), 143-215.3(c), 143B-282(1)(u),
E„f: February 1, 1976;
Amended Eff. December 1, 1984; September 1, 1984
RRC Objection Eff. July 18, 1996 due to lack of statutory authority and ambiguity;
Recodied from 15A NCAC 2H.0502 Eff October 1, 1996,
Amended Eff. October 1, 1996
.0504 HEARING
(a) Public Hearing on Certification. If the Director determines that it is in the public interest that a public
hearing for the purpose of reviewing public comment and additional information be held prior to granting or denying
certification, the Director shall so notify the applicant by registered or certified mail, return receipt requested, and
shall publish and give notice as required in Rule .0503(d) and (e) of this Section. Such hearing shall be held within
90 days following date of notification. The record of each hearing held under this Paragraph shall remain open for
a period of 30 days.
.1
NORTH CAROLINA ADMINISTRATIVE CODE 10115196 Page 2
EHNR - ENVIRONMENTAL MANAGEMENT T15A: 02H.0500
(b) Hearing for Applicant Upon Certification Denial. An applicant whose certification is denied or granted
subject to unacceptable conditions, shall have the right to a contested case hearing pursuant to the provisions of G.S.
150B-23.
History Note. Authority G.S. 143-215.3(a)(1); 143-215.3(c); 143B-282(1)(u);
Eff. February 1, 1976;
Amended E„ . July 1, 1988; December 1, 1984;
RRC Objection E„f: July 18, 1996 due to lack of statutory authority and ambiguity;
Recodified from 15A NCAC 2H. 0503 Eff. October 1, 1996;
Amended Eff. October 1, 1996.
.0505 DELEGATIONS
History Note. Authority G.S. 143-215.3(a)(1), 143-215.3(c);
Eff. February 1, 1976;
Repealed Eff. December 1, 1984.
.0506 REVIEW OF APPLICATIONS
(a) In evaluating requests for certification based on the procedures outlined in Paragraphs (b) through (e) of this
Rule, the Director shall determine if the proposed activity has the potential to remove or degrade those significant
existing uses which are present in the wetland or surface water. Activities which would not remove or degrade
existing uses shall be reviewed according to the procedures found in Subparagraph (c)(2)-(5) of this Rule. Those
activities covered by general certifications [15A NCAC 2H .0501(c)(2)] which do not require written concurrence
from the Division shall be deemed certified if the conditions of the certification are followed and may proceed
without the review procedures outlined in Paragraphs (b) through (e) of this Rule. An applicant may also
demonstrate that designated uses are not present at a particular site using a wetland evaluation procedure approved
by the Director according to the criteria found in 15A NCAC 2B .0103(c); otherwise the designated uses as outlined
at 15A NCAC 2B .0231(a)(1)-(6) are assumed to exist in all classes of wetlands, and the appropriate review
procedures shall be undertaken. Certification shall be issued where the Director determines water quality standards
are met, including protection of existing uses.
(b) The Director shall issue a certification upon determining that existing uses are not removed or degraded by
a discharge to classified surface waters for an activity which:
(1) has no practical alternative under the criteria outlined in Paragraph (f) of this Rule;
(2) will minimize adverse impacts to the surface waters based on consideration of existing topography,
vegetation, fish and wildlife resources, and hydrological conditions under the criteria outlined in
Paragraph (g) of this Rule;
(3) does not result in the degradation of groundwaters or surface waters;
(4) does not result in cumulative impacts, based upon past or reasonably anticipated future impacts, that cause
or will cause a violation of downstream water quality standards;
(5) provides for protection of downstream water quality standards through the use of on-site stormwater
control measures; and
(6) provides for replacement of existing uses through mitigation as described at Subparagraphs (h)(1) of this
Rule.
(c) The Director shall issue a certification upon determining that sufficient existing uses are not removed or
degraded by a discharge to Class WL wetlands as defined at 15A NCAC 2B .0101(c)(8), for an activity which:
(1) has no practical alternative as described in Paragraph (f) of this Rule, or impacts less than three acres of
Class WL wetlands;
(2) will minimize adverse impacts to the wetland based on consideration of existing topography, vegetation,
fish and wildlife resources, and hydrological conditions under the criteria outlined in Paragraph (g) of this
Rule; or impacts less than one acre of wetland within 150 feet (including less than 1/3 acre of wetland
within 50 feet), of the mean high water line or normal water level of any perennial or intermittent water
body as shown by the most recently published version of the United State Geological Survey 1:24,000
(7.5 minute) scale topographical map or other site specific data;
(3) does not result in the degradation of groundwaters or surface waters;
(4) does not result in cumulative impacts, based upon past or reasonably anticipated future impacts, that cause
or will cause a violation of downstream water quality standards;
(5) provides protection for downstream water quality standards through the use of on-site stormwater control
NORTH CAROLINA ADMINISTRATIVE CODE 10115196 Page 3
EHNR - ENVIRONMENTAL MANAGEMENT TISA: 02H .OS00
measures; and
(6) provides for replacement of existing uses through wetland mitigation under U.S. Army Corps of Engineers
requirements or as described in Subparagraph (h)(1)-(8) of this Rule.
(d) The Director shall issue a certification upon determining that significant existing uses are not removed or
degraded by a discharge to Class SWL wetland as defined at 15A NCAC 2B .0101(d)(4),wetlands that are
contiguous to waters designated as ORW, HQW, SA, WS-I, WS-1I or Trout, or wetlands that are contiguous to
rivers designated as a North Carolina or National Wild and Scenic River for an activity which satisfies
Subparagraphs (c)(2)-(5) of this Rule, and:
(1) for wetlands classified as coastal wetlands pursuant to 15A NCAC 7H .0205:
(A) has no practical alternative as described in Paragraph (f) of this Rule; and
(B) is water dependent and requires access to water as a central element of its basic function, although,
projects funded by government agencies may be exempted from this requirement; and
(2) provides for replacement of existing uses through wetland mitigation under U.S. Army Corps of Engineers
requirements, or as described in Subparagraphs (h)(1)-(7) and (9) of this Rule.
(e) The Director shall issue a certification upon determining that significant existing uses are not removed or
degraded by a discharge to wetlands of exceptional state or national ecological significance including but not limited
to Class UWL wetlands, and wetlands that have been documented to the satisfaction of the Director as habitat
essential for the conservation of state or federally listed threatened or endangered species, provided that the wetlands
have been so classified or designated prior to the date of application for certification or a draft environmental impact
statement has been submitted to the Director, for an activity which satisfies Subparagraphs (c)(2)-(5) and (d)(1)-(2)
and:
(1) the wetland impacts are necessary for the proposed project to meet a demonstrated public need; and
(2) provides for replacement of existing uses through wetland mitigation under U.S. Army Corps of Engineers
requirements, or as described in Subparagraphs (h)(1)-(7) and (10) of this Rule.
(f) A lack of practical alternatives may be shown by demonstrating that, considering the potential for a reduction
in size, configuration or density of the proposed activity and all alternative designs the basic project purpose cannot
be practically accomplished in a manner which would avoid or result in less adverse impact to surface waters or
wetlands.
(g) Minimization of impacts may be demonstrated by showing that the surface waters or wetlands are able to
continue to support the existing uses after project completion, or that the impacts are required due to:
(1) The spatial and dimensional requirements of the project; or
(2) The location of any existing structural or natural features that may dictate the placement or configuration
of the proposed project; or
(3) The purpose of the project and how the purpose relates to placement, configuration or density.
(h) Replacement or mitigation of unavoidable losses of existing uses shall be reviewed in accordance with the
following guidelines:
(1) The Director shall coordinate mitigation requirements with other permitting agencies that are requiring
mitigation for a specific project. Mitigation required by the U.S. Army Corps of Engineers shall be
considered to constitute the mitigation required by the certification unless the Director determines that the
mitigation proposal does not meet the criteria established in Subparagraph (6) of this Paragraph.
(2) Mitigation shall not be required for impacts to Class WL wetlands of less than one acre.
(3) Participation in wetland restoration programs coordinated by the Department of Environmental, Health,
and Natural Resources shall be preferred to individual project mitigation whenever the Director finds that
such participation is available and satisfies the other requirements of this Paragraph, unless the applicant
can demonstrate that participation in these restoration programs is not practical. Mitigation sites approved
by the U.S. Army Corps of Engineers shall be deemed to be consistent with the Department's restoration
plan.
(4) Acceptable methods of wetlands mitigation are listed below in the order of preference:
(A) Restoration: the re-establishment of wetland hydrology and vegetation in an area where it
previously existed.
(B) Creation: the construction of a wetland in an area where wetlands did not exist in the recent past.
(C) Enhancement: increasing one or more of the functions of an existing wetland by manipulation of
vegetation or hydrology.
(D) Preservation: protection of wetlands through purchase, donation or conveyance of a conservation
easement to an appropriate government or non-profit agency for management.
(5) Restoration is the preferred method of wetlands mitigation. The other methods may be utilized if the
applicant can demonstrate that restoration is not practical or that the proposed alternative is the most
. V
NORTH CAROLINA ADMINISTRATIVE CODE 10/15196 Page 4
EHNR - ENVIRONMENTAL MANAGEMENT T15A: 0211.0500
ecologically viable method of replacing the lost functions and values.
(6) All mitigation proposals shall provide for the replacement of wetland acres lost due to the proposed
activity at a minimum of a 1:1 ratio through restoration or creation prior to utilizing enhancement or
preservation to satisfy the mitigation requirements, unless the Director determines that the public good
would be better served by other types of mitigation.
(7) Wetlands mitigation shall be conducted based on the following ratios (acres mitigated to acres loss); 4:1,
for wetlands located within 150 feet of the mean high water line or normal water level of any perennial
or intermittent water body as shown by the most recently published version of the United States
Geological Survey 1:24,000 (7.5 minute) scale topographical map; 2:1, for wetlands located between 150
feet and 1,000 feet from the mean high water line or normal water level of any perennial or intermittent
water body as shown by the most recently published version of the United States Geological Survey
1:24,000 (7.5 minute) scale topographical map; and 1:1, for all other wetlands. For linear projects which
impact less than 3 acres of wetlands the ratio shall be 2:1 regardless of the distance from surface waters.
The above ratios apply only to restoration. The acres of required mitigation for the other types of
mitigation shall be determined by multiplying the above ratios by 1.5 for creation, 2 for enhancement,
and 5 for preservation. The above ratios do not apply to approved mitigation sites where the state and
federal review agencies have approved credit/debit ratios. This Subparagraph shall not apply to general
certifications until the Department has established a wetlands restoration program or until January 1, 1997,
whichever occurs first.
(8) Mitigation for impacts to wetlands designated in Paragraph (c) of this Rule shall be conducted within the
same river basin and physiographic province when practical. Unavoidable losses of wetlands adjacent to
waters classified as WS-III shall be replaced within the water supply watershed when practical.
(9) Mitigation for impacts to wetlands designated in Paragraph (d) of this Rule shall be of the same wetland
type and located within the same river sub-basin when practical. Mitigation for impacts to wetlands
adjacent to waters classified as WS-I or WS-II shall be replaced within the water supply watershed when
practical.
(10) Mitigation for impacts to wetlands designated in Paragraph (e) of this Rule shall be of the same wetland
type and within the same watershed when practical.
(i) The Director shall not duplicate the site-specific application of any guidelines employed by the United State
Army Corps of Engineers in evaluating permit applications under 33 U.S.C. 1344 and applicable federal regulations.
History Note. Authority G.S. 143-215.3(a)(1); 143-215.3(c); 143B-282(1)(u),
RRC Objection Eff. July 18, 1996 due to lack of statutory authority and ambiguity;
Eff. October 1, 1996.
.0507 ISSUANCE OF CERTIFICATION
(a) Time Limit for Final Action on Certification Application. All applications for certification shall be granted
or denied within 60 days after receipt at the offices of the Director in Raleigh, North Carolina. Failure to take final
action within 60 days shall result in a waiver of the certification requirement by the Director, unless:
(1) The applicant agrees, in writing, to a longer period;
(2) Final decision is to be made pursuant to a public hearing;
(3) Applicant fails to furnish information necessary to the Director's decision;
(4) Applicant refuses the staff access to its records or premises for the purpose of gathering information
necessary to the Director's decision or;
(5) Information necessary to the Director's decision is unavailable.
(b) Tmie Limit for Final Action on Certification Application After Hearing. All applications for certification
shall be granted or denied within 60 days after public hearing. Failure to take final action within 60 days shall
result in a waiver of the certification requirement by the Director unless the applicant otherwise agrees in writing,
or unless Subparagraph (a)(3), (4), or (5) of this Rule shall apply.
(c) Conditions of Certification. Any certification issued pursuant to this Rule may contain such conditions as
the Director shall deem necessary to insure compliance with Sections 301, 302, 303, 306, and 307 of the Federal
Water Pollution Control Act Amendments.
(d) Modification or Revocation of Certification
(1) Any certification issued pursuant to this Rule shall be subject to revocation or modification for violation
of conditions of 301, 302, 303, 306, and 307 of the Federal Water Pollution Control Act Amendments.
(2) Any certification issued pursuant to this Rule shall be subject to revocation or modification upon a
determination that information contained in the application or presented in support thereof is incorrect or
NORTH CAROLINA ADMINISTRATIVE CODE 10115196 Page 5
EHNR - ENVIRONMENTAL MANAGEMENT
TISA: 02H.0500
if conditions under which the certification was made have changed.
(e) Notification of Unapproved Application. In the event that the Director denies the application for certification
or for any reason is unable to approve the application, the Director shall so notify the applicant by certified or
registered mail, return receipt requested, specifying in such notification the reasons for the denial or inability to
approve; and a copy of the notification shall be mailed to the appropriate federal licensing or permitting agency and
EPA.
History Note: Statutory Authority G.S. 143-215.3(a)(1); 143-215.3(c); 143B-282(1)(u);
Eff. February 1, 1976;
Amended Eff.. July 1, 1988; December 1, 1984;
RRC Objection E„8`: July 18, 1996 due to lack of statutory authority and ambiguity,
Recodifed from 15A NCAC 2H .0504 Eff. October 1, 1996;
Amended Eff. October 1, 1996.
1000 copies of this document were printed at a cost of $ 181.80 or $ .18 per copy

. V
NORTH CAROLINA ADMINISTRATIVE CODE 10115196 Page 6
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Baker and Associates
A Unit of Michael Baker Corporation
200 CentrePort Drive, Suite 225
Greensboro, NC 27409
[phone]
FAX [phone]
February 13, 2003
Mr. Todd St. John, P.E.
North Carolina Division of Water Quality
1650 Mail Service Center
Raleigh, NC 27699-1650
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Subject: Stormwater Management Plan
Piedmont Triad International Airport
Dear Mr. St. John:
Baker and Associates (Baker) has been in contact with you over the past two years regarding the
Stormwater Management Plan for the Piedmont Triad Airport Authority (PTAA) and the 401 Water
Quality Permit. Previous correspondence during the 2001 calendar year dated August 22, September 12,
October 9 and the most recent correspondence dated March 5, 2002 addressed water quality issues relating
to the operation of the proposed stormwater management ponds for the future development a the Piedmont
Triad International Airport
The subject of these past discussions was the operation of the ponds as they relate to the removal of Total
Suspended Solids (TSS). As you are aware, the proposed stormwater management ponds have been
designated as dry detention ponds and the published TSS removal rate for dry ponds is 50 percent. It is
understood that additional measures are to be put in place in order to reach the Division of Water Quality's
goal of 85 percent removal of TSS prior to the runoff entering Brush Creek. The March 5, 2002 letter as
authored by Baker identified a plan to strive toward reaching the 85 percent TSS removal goal. In March
2002, the design of the ponds had not started and the level of detail that is desired by your office for review
and comment was not available.
Attached are the final grading and pond configuration drawings of the three proposed dry ponds. The
ponds will operate in the following manner:
• The runoff from the one inch storm will be contained in each pond to the elevation of the principal
riser
• The one inch storm - temporary water quality storage volume - will discharge over a four day period
through a dewatering orifice
• The principal spillway will discharge into an energy dissipator and then into the level spreaders under
low flow conditions.
• The ten year storm event will discharge through the principal spillway
• The one hundred year storm will discharge through a combination of the principal spillway and the
emergency spillway
Level spreaders will be constructed at the outfall of the energy dissipators that control the flow from the
principal spillways. These level spreaders have a minimum bottom width of one foot with maximum
bottom width of 5 feet. The level spreaders are designed that the crest elevation of the spreader is
undisturbed ground at a constant elevation. These level spreaders have been sized in accordance with the
level spreader design options as published by the DWQ which is the option to discharge the one-inch
rainfall at a maximum of one cubic foot per second per one hundred feet of level spreader for forested
areas. The following is a summary of the level spreader design:
• Pond F-1- discharge rate of 1.65 cubic feet per second - the proposed length of level spreader is 210
linear feet. Crest elevation 805.
• Pond F-2 - discharge rate of 1.71 cubic feet per second - the proposed length of level spreader is 275
linear feet. Crest elevation 804.
• Pond F-3 - discharge rate of 1.30 cubic feet per second - the proposed length of level spreader is 215
linear feet. Crest elevation 810.
The level spreaders have been proposed to the maximum extent possible in order to provide as much time
as possible for the settling of suspended solids prior to the runoff entering the buffer.
Attached are the calculations for the peak discharge through the dewatering orfices into the level spreader.
The water quality system is comprised of four components that operate in series to remove TSS prior to the
runoff entering Brush Creek. This system utilizes the existing natural system in combination with the
construction of sediment removal tools as defined in the Best Management Practices manual. Table
Number 1 reflects the combination of the TSS removal percentages for each Best Management Practice
(BMP) structure that is proposed for the ultimate build out of the site.
Should you require any additional information regarding the efficiency of the proposed water quality
controls for the development of the site, please contact this office at any time.
Sincerely,
PA?KER AND ASSOCIATES
Wan R. Berenbro ,k
Project Manager
Attachments
Table 1
Pond Drawings SG 10 and SG 11
Dewatering Orifice Spreadsheet
cc: Mickie Elmore (w/aft)
Bill Cooke (w/att)
orifice equation

Dewaterin Orifices for Ponds F-1, F-2 and F-3

orifice equation calculat ions

Q=ca 2 h ^.5 pipe diame ter

C= 0.6 h= top of grate - pipe centerline
9= 32.2

tructure

diameter of
dewatering
orifice (inches)

diameter of
dewatering
orifice (feet)

(ft^2 Crest of Principal
Spillway /
Temporary Water
Quality Storage
Elevation

invert of
dewatering
orifice

Maximum
Head
(feet)
Q Maximum
Dewatering
Discharge
(CFS)

Principal
Riser

F-1 5 0.42 0.14 817.25 810.75 6.29 1.65

F-2 5 0.42 0.14 817.25 810.25 6.79 1.71

F-3 5 0.42 0.14 826.3 821.59 4.50 1.39
Page 1
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Richard L. Phillips
Professional Engineer
N.C. Divisiop of Water Quality
ATTN: Cyndi Karoly
1650 Mail Service Center
Raleigh, NC 27699-1650
RE: Fed Ex Water Quality Certification
September 13, 2002
Attached are the minutes of a meeting July 17a' with the PTAA engineering staff. Please
make these available to Mr. John Dorney and other decision-makers in DWQ.
I talked to Mr. Dorney yesterday, and he suggested I send these in and also call for an
appointment with you and possibly Mr. StJohn. To me, the minutes reflect the current
thinking on the part of the Airport Authority. Because I am concerned with their
approach, I share these with you. These minutes were accepted by the ABEQ (Guilford
Co. Advisory Board for Environmental Quality) at their August meeting.
Thank you,
Richard L. Phillips, P E

;rl

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of
V'
Construction • Erosion Control • Water
J1 };? `3955 Bittle Road
. SEP 1 7 2002
Gibsonville, NC 27249
Wa TLANDS [phone]
DPhillengr@aol-com
1 6
Y
Quality • Constructed ? 1etlands

MEETING JULY 17, 2002
ABEQ sub-committee members John Robinson, Mike Wescott, and Dick
Phillips met on July 17th with PTAA engineering staff. These were
Mickie Elmore, Kevin Baker, Alan Berenbrock, and Melinda King. The
following is a record of items discussed plus some additional comments
by sub-committee members.
1. PLAN. The PLAN (Stormwater Management Plan) is an "ongoing
document, subject to change as new information becomes available."
It is "conceptual", containing examples and location and examples of
ponds. It is "subject to change as new information becomes
available."
2. OBJECTIVES. Mr. Ellmore stated that PTAA is committed to protecting
our water quality, following the most stringent of State or County
requirements, and assured us "that a dam safety permit will be secured
if needed." In addition to water quality protection, their objective
is to limit post-development flow to pre-development flow for the 10
year storm, release the one inch storm runoff over 4-6 days (Guilford
Co. regs), and pass the 100 year storm through the emergency spillway.
3. GRADING PLAN. Baker &Associates are working on the final grading
plan at this time, and expect it to be done in late 2002. They are
planning the F series of ponds also and will check with ABEQ at the 50
or 75% point of completion.
4. TEMPORARY STORAGE. A considerable amount of time was spent
discussing the design of the F series ponds. They appear to be very
short of the required temporary storage needed (probably less than half
that required) when the 10 year storm occurs. With the present plan,
flow would occur through the emergency spillway when this storm occurs,
thus they would not meet the 10 year criteria. It was agreed that Alan
would re-examine the model, then contact Dick Phillips. The
discrepancies may be due to the model used, the mixing of the Rational
Formula with some type of hydrograph, and the routing technique. A
suggestion was made that perhaps too much information is provided in
the Plan, and this should be for internal use only. This was countered
by the fact that the Plan is a public document and is the basis for the
401 permit and for future consulting contracts. Thus it needs to be
based on correct hydraulics and hydrology, even though it is a
"document in progress."
5. DAM SAFETY PERMIT. The reason that consideration of a dam safety
permit is so critical in the planning stage is that it will affect the
size and the location of all structures, particularly the F series.
ABEQ's calculations show that the present F series ponds already
require a permit, even though the PLAN shows lightly less than 10 acre
feet to the emergency spillway. When the additional storage is
provided to pass the 10 year storm, this undoubtedly will increase the
storage far belong the 10 acre feet. ADDITIONALLY, North Carolina
requires the storage measured to top of dam, not emergency spillway as
shown in the Plan. The F series ponds are really major structures, and
sub-committee members were pleased that they are being designed as
part of the grading plan at this time.
« f K..
6. OTHER DETENTION PONDS. It was the general consensus that the
remaining detention ponds are not as critical as the F series, and
probably can be left to consultants to design in the future. ABEQ's
review show these to also be deficient in temporary storage and this
should be addressed now along with the review of the F ponds.. The
sub-committee was disappointed to learn that the remaining "may also
become dry ponds."
7. EMERGENCY SPILLWAY DESIGN. There was a length discussion of the "C"
values for emergency spillway flow. Different values can be obtained,
depending on the source, ranging from 2.63 to 3.00. ABEQ's position
is that water surface profiles should be used to determine correct
flow (or tables incorporating this). Mike W. offered a technique,
which could be used. ABEQ reluctantly agreed to use a C of 3.0,
currently acceptable to Guilford County. Dick Phillips for the record
stated that "It is not adequate engineering design for these major
structures to simply drop the flow over a low point on the dam and
release over the downstream slope." All agreed. The magnitude of flow
from 240 acres of impervious areas during the 100 year storm should be
noted. This is in the order of 145 acre feet, almost 900 of which will
flow through the emergency spillway(s). Further restrictions will be
added to the design since these will undoubtedly require a dam safety
permit and State review. It is quite possible some type of reinforced
concrete spillway will be required, particularly considering the
limited space between the F structures and the jurisdictional wetlands.
The use of riprapped emergency spillways for this type of flow was
seriously questioned by Phillips.
8. WATER QUALITY. Water quality was discussed at length, particularly
with the F series ponds. The majority of ABEQ members do not believe
that the proposals in the PLAN go far enough in reducing pollutants,
that is they are not the "Best Available Technology." Also ABEQ does
not accept as adequate the minimum State standard of 85% removal of TSS
(total suspended solids) considering the proximity of the pollution
source to municipal water supplies. It is ABEQ's belief that either
(1) wet detention ponds should be used, or (2) extended dry detention
ponds with further treatment in existing wetlands or preferably
constructed wetlands..
9. WETLAND USE. The efficient use of existing wetlands poses a very
difficult task for the F structures, as three things are required for
treatment: (1)Sheet flow, (2) very slow velocity, less than 2 fps, and
(3) several days of detention time, 14 days being the preferred.
Conveying flow from the detention structures to the wetlands will be a
major challenge, and use of "grass swales and level spreaders at 150
feet" below principal spillway pipes will not be adequate according to
Phillips, and will be a continual maintenance headache in order to
secure treatment. The use of a separate piping system to distribute
the one inch of temporary water quality storage was discussed,
particularly the use of distribution pipes separate and apart from the
principal spillway. Several suggestions were given. Mr. Wescott's
experience with the detention ponds at Oak Hollow Mall can be very
useful.
10. PLAN CHANGES. The present PLAN is being reviewed by a number of
regulatory agencies, and ABEQ's position is that if DWQ approves the
plan as presently written as to structure size and location and use or

non-use of wetlands, this locks the PTAA into the plan as presented.
For example, if the present wet detention ponds alongside the new
runway were to be changed later to dry ponds, this would be a violation
of the PLAN, and not in keeping with a 401 water quality certification.
If it is anticipated that if changes are necessary, they should be
made at this time and DWQ notified. ABEQ's position is that in
keeping with (8) above, that there are two solutions-- either wet
detention ponds, or extended dry detention ponds followed by flow
through wetlands. If wetlands downstream of the ponds are not
feasible, then this alternative is no longer feasible. In any event,
ABEQ believes that the PLAN sets the design of all these structures,
and there is no leeway once the 401 permit is issued based on a precise
PLAN, which DWQ has reviewed and accepted.
11. SUMMARY. The meeting was cordial and appreciated by ABEQ sub-
committee members and they look forward to further contact to address
a number of questions. The bottom line is that a number of decisions
by regulatory agencies are ongoing, all based on the current PLAN. For
this reason we believe the PLAN should reflect any changes under
consideration, and DWQ should be notified of pending changes so these
can be considered in their deliberations, all before the 401 water
quality certification is issued.
. 1
00
Richard L. Phillips
Professional Engineer
N.C. Division of Water Quality
ATTN: Cyndi Karoly
1650 Mail Service Center
Raleigh, NC 27699-1650
RE: Fed Ex Water Quality Certification
U
3955 Bittle Road
Gibsonville, NC 27249
[phone]
[e-mail]
September 13, 2002
Attached are the minutes of a meeting July 17th with the PTAA engineering staff. Please
make these available to Mr. John Dorney and other decision-makers in DWQ.
I talked to Mr. Dorney yesterday, and he suggested I send these in and also call for an
appointment with you and possibly Mr. StJohn. To me, the minutes reflect the current
thinking on the part of the Airport Authority. Because I am concerned with their
approach, I share these with you. These minutes were accepted by the ABEQ (Guilford
Co. Advisory Board for Environmental Quality) at their August meeting.
Thank you,
Richard L. Phillips, P E

Construction e Erosion Control • Water Quality • Constructed Wetlands
MEETING JULY 17, 2002
ABEQ sub-committee members John Robinson, Mike Westcott, and Dick
Phillips met on July 17th with PTAA engineering staff. These were
Mickie Elmore, Kevin Baker, Allan Berenbrok, and Melinda King. The
following is a record of items discussed plus some additional comments
by sub-committee members.
1. PLAN. The PLAN (Stormwater Management Plan) is an "ongoing
document, subject to change as new information becomes available."
It is "conceptual", containing location and examples of ponds.
2. OBJECTIVES. Mr. Ellmore stated that PTAA is committed to protecting
our water quality, following the most stringent of State or County
requirements, and assured us "that a dam safety permit will be secured
if needed." In addition to water quality protection, their objective
is to limit post-development flow to pre-development flow for the 10
and the 2 year storms, release the one inch storm runoff over 2-5 days
and pass the 100 year storm through the emergency spillway. Note:
Guilford Co. regs are 4-6 days and ABEQ's position has always been 8-10
days for the release rate, and limit post-development flow for the 25
year storm, see Position Statement of 5-12-99, and subsequent
statements.
3. GRADING PLAN. Baker &Associates are working on the final grading
plan at this time, and expect it to be done in late 2002. They are
planning the F series of ponds also and will check with the sub-
committee at the 50 or 75% point of completion.
4. TEMPORARY STORAGE. A considerable amount of time was spent
discussing the design of the F series ponds. They appear to be very
short of the required temporary storage needed (probably less than half
that required) when the 10 year storm occurs. With the present plan,
flow would occur through the emergency spillway when this storm occurs,
thus they would not meet the 10 year criteria. It was agreed that Alan
would re-examine the model, then contact Dick Phillips. The
discrepancies may be due to the model used, the mixing of the Rational
Formula with some type of hydrograph, and the routing technique. A
suggestion was made that perhaps too much information is provided in
the Plan, and this should be for internal use only. This was countered
by the fact that the Plan is a public document and is the basis for the
401 permit and for future consulting contracts. Thus it needs to be
based on correct hydraulics and hydrology, even though it is a
"document in progress."
5. DAM SAFETY PERMIT. The reason that consideration of a dam safety
permit is so critical in the planning stage is that it will affect the
size and the location of all structures, particularly the F series.
ABEQ's calculations show that the present F series ponds already
require a permit, even though the PLAN shows lightly less than 10 acre
feet to the emergency spillway. When the additional storage is
provided to pass the 10 year storm, this undoubtedly will increase the
storage far belong the 10 acre feet. ADDITIONALLY, North Carolina
requires the storage measured to top of dam, not the emergency
spillway level as shown in the Plan. The F series ponds are really
major structures., and sub-committee members were pleased that they are
being designed as part of the grading plan at this time.
, ,,,. K
6. OTHER DETENTION PONDS. It was the general consensus that the
remaining detention ponds are not as critical as the F series, and
probably can be left to consultants to design in the future. ABEQ's
review show these to also be deficient in temporary storage and this
should be addressed now along with the review of the F ponds. The
sub-committee was disappointed to learn that the remaining "may also
become dry ponds." 4`
7. EMERGENCY SPILLWAY DESIGN. There was a lengthy discussion of the
"C" values for emergency spillway flow. Different values can be
obtained, depending on the source, ranging from 2.63 to 3.00.
Phillips' position is that water surface profiles should be used to
determine correct flow (or tables developed from these). Mike W.
offered a technique, which could be used. The sub-committee
reluctantly agreed to use a C of 3.0, currently acceptable to Guilford
County. Dick Phillips for the record stated that "It is not adequate
engineering design for these major structures to simply drop the flow
over a low point on the dam and release over the downstream slope."
All agreed. The magnitude of flow from 240 acres of impervious areas
during the 100 year storm should be noted. This is in the order of 145
acre feet, almost 90% of which will flow through the emergency
spillway(s). Further restrictions will be added to the design since
these will undoubtedly require a dam safety permit and State approval.
It is quite possible some type of reinforced concrete spillway will be
required, particularly considering the limited space between the F
structures and the jurisdictional wetlands. The use of riprapped
emergency spillways for this type of flow was seriously questioned by
Phillips.
8. WATER QUALITY. Water quality was discussed at length, particularly
with the F series ponds. The majority of ABEQ members do not believe
that the proposals in the PLAN go far enough in reducing pollutants,
that is they are not the "Best Available Technology." Also the sub-
committee does not accept as adequate the minimum State standard of 85%
removal of TSS (total suspended solids) considering the proximity of
the pollution source to municipal water supplies. It is ABEQ's belief
that either (1) wet detention ponds should be used, or (2) extended dry
detention ponds with further treatment in existing wetlands or
(preferably) constructed wetlands. (Refer to previous ABEQ position
statements.)
9. WETLAND USE. The efficient use of existing wetlands poses a very
difficult task for the F structures, as three things are required for
treatment: (1)Sheet flow, (2) very slow velocity, less than 2 fps, and
(3) several days of detention time, 14 days preferred. Conveying flow
from the detention structures to the wetlands will be a major
challenge, and use of "grass swales and level spreaders at 150 feet"
below principal spillway pipes will not be adequate according to
Phillips, and will be a continual maintenance headache in order to
secure treatment. The use of a separate piping system to distribute
the temporary water quality storage was discussed, particularly the
use of distribution pipes separate and apart from the principal
spillway. Several suggestions were given. Mr. Westcott's experience
with the detention ponds at Oak Hollow Mall can be very useful.

10. PLAN CHANGES. The present PLAN is being reviewed by a number of
regulatory agencies, and the sub-committee's position is that if DWQ
approves the plan as presently written as to structure size and
location and use or non-use of wetlands, this locks the PTAA into the
plan as presented. For example, if the present wet detention ponds
alongside the new runway were to be changed later to dry ponds, this
would be a violation of the PLAN, and not in keeping with a 401 water
quality certification. If it is anticipated that if changes are
necessary, they should be made at this time and DWQ notified. If
wetlands downstream of the ponds are not feasible, then the alternative
of dry ponds only is no longer feasible. In any event, the sub-
committee believes that the PLAN sets the location and type of these
structures, and there will be no leeway once the 401 permit is issued
based on the PLAN as submitted to DWQ (which they will review and
accept as part of their approval process.)
11. SUMMARY. The meeting was cordial and appreciated by ABEQ sub-
committee members and they look forward to further contact to address
a number of questions. The bottom line is that a number of decisions
by regulatory agencies are ongoing, all based on the current PLAN. For
this reason we believe the PLAN should reflect any changes under
consideration, and DWQ should be notified of pending changes so these
can be considered in their deliberations, all before the 401 water
quality certification is issued.
4

Post Office Box 3427
Greensboro, N.C. 27402
[phone]
Guilford County
ADVISORY BOARD FOR ENv'VIRONTMENTAL QUALITY
Mr. Greg Thorpe November 15, 2001
NC Department of Environment and Natural Resources
Division of Water Quality
1650 Mail Service Center
Raleigh, NC t7s' i- Dear Mr. Thorpe, RE: FedEx Water Quality Certification

I realize the official comment period is over but I have now had the opportunity to
receive and review the Stormwater Management Plan (which was not available during the
comment period). Thus I offer the following for your deliberations on this project.
This project has more water quality impact than any other in North Carolina and as such
deserves the highest possible level of protection for our municipal water supplies. It is
my opinion that the Plan does not go far enough toward this end. I base this on a review
of segments of the plan which show a number of inadequacies and errors (see the
attachment).
I trust these will be helpful in your analysis of this project. If you would like to explore
these further, I would be happy to discuss these in person at your time and convenience.
My home phone is 336 698 0028.
Sincerely,
Richard L. Phillips, PE
Member, ABEQ
Attachment
M
CONCERNS--STORMWATER MANAGEMENT PLAN--PTAA Nov 15, 01
1. Emergency spillway flows are incorrectly calculated, ranging in an error of 67% for a
1.0 foot depth, to a 33% error for a 3.0 foot depth. As a result, the top of dam
elevations are too low and should be approximately 0.5 feet higher.
2. The Plan uses orifice flow to calculate discharge through the principal spillways.
This is not correct for higher stages when the control passes to pipe flow.
3. The research shows dry detention ponds to be only 30 to 35% effective in removing
TSS. If dry detention ponds are used, the temporary water quality storage should be
directed to a constructed wetland downstream (an extended detention wetland.) This
has not been planned.
4. The use of grass waterways to achieve a 35% removal of pollutants is not supported
by the literature. It is true that a vegetated filter strip using sheet flow is quite
effective in removing pollutants, but the flow characteristics in a waterway are more
concentrated with a higher velocity and short contact time. For this reason, the
coupling of dry detention ponds with grass waterways is without a doubt insufficient
to achieve a 85% removal rate. The literature would rate this combination as probably
less than 50% efficient.
5. The 0.8 inches of runoff from the impervious areas should be increased to one inch.
It is acknowledged that for Runoff Curve Number 98 there will be slightly less than
one inch of runoff. However, a better design for a watershed which is completely
impervious is to use 100% runoff. In the case of F-1 (as well as F-2 and F-3) the
temporary water quality storage should be 6.67 acre feet rather than 6.33 acre feet.
6. Although the Rational Formula has been in existence for the last 100 years or so,
there are recent hydrologic methods which are improved. Using the SCS (now
NRCS) methodology, the peak flow for P-7 is in an additional 39%, and for F-1, an
additional 17%. The second problem with the Rational Formula is that it computes
only peak flows and was never intended for the design of storage and detention
structures.
7. Temporary storages were computed for P-7 and F-1 using SCS TR-55 and compared
to the model used in the Plan. P-7 requires 7.04 acre feet and F-1 requires 15.3 acre
feet. In both cases the available storage is insufficient, providing only 56% and 48%
of the required storage respectively. This would (like 41 above) raise the top of the
dam
8. It appears that the planners had an overriding concern to avoid a dam safety permit
from NC DENR, as this is addressed on all the design forms available. This approach
limits the solution and in some cases is not the most economical. For example, the
runoff from the 240 acres of impervious surfaces is presently divided into 3 sites (17-
1,2, 3). A better solution might be to use one larger structure requiring a dam safety
permit and direct the temporary water quality storage to an extended detention
wetland. As it is, the three structures appear to be "hung" on the side of the
embankment immediately adjacent to the existing wetlands. In any event, dry
detention ponds will not sufficiently remove the pollutants from 240 acres of
impervious surfaces.
'^ s
Richard L. Phillips
Professional Engineer
Mr. William G. Ross, Jr.
Secretary, NC DENR
1601 Mail Service Center.
Raleigh, NC 27599-1601
Re: FEDEX hub, Greensboro, NC.
Dear Mr. Ross,

3955 Bittle Road
Gibsonville, NC 27249
[phone]
[e-mail]
June 17, 2002
This is a follow-up to Elaine Stover's letter of January 29, 2002
which expresses the opinion that the Piedmont Triad Airport Authority
has not demonstrated that they will adequately protect the water
supplies of Greensboro with the best available technology. It is
directed to you since it involves two Divisions in your Department. In
addition to the water quality issues listed in that letter, I have
additional concerns which warrant your consideration.
1. The Airport Authority has shown an overriding desire to avoid any
future review by your Department, as they repeatedly state in their
documents that none of their ponds will require a dam safety permit
as all have been sized below the 10 acre feet requirement.
2. There are a number of design deficiencies in the hydraulics and
hydrology of detention dams shown in the Stormwater Management Plan
with the result that only about half of the required storage has been
provided. Details of this are provided in an attached letter written
November 15th '2001 to Mr. Greg Thorpe, Division of Water Quality.
3. Once DENR grants the 401 Water Quality Certification, the Airport
Authority is no longer subject to any oversight by your Department as
"The PTAA is considered a local authority permitted by NCDENR to
develop its own stormwater ordinances..."
The end result of all this is that there seems to be a determined
effort to avoid any oversight by your Department after the 401 Water
Quality Certification is granted. As a result water quality will be
diminished. For this reason, I suggest you ask the Dam Safety
personnel in the Division of Land Quality to: (1) review Sites F-1 and
P-7 to see if they meet the 24 hour-25 year criteria (2)determine if
they are governed by the Dam Safety Law of 1967 (as amended). I know
your staff is busy, but I believe this action would be in the best
interests of all citizens of Guilford County as well as the State of
North Carolina.
May I please have eply at your earliest convenience?
Sincerely, f
Richard L. Phillips
Attach: Nov. 15, 01 letter to Greg Thorpe
January 29, 02 letter to William Ross,.Jr.
Construction • Erosion Control Water Quality 0 Constructed Wetlands

July 11, 2002 ABEQ Meeting.
Questions from ABEQ to PTIA officials - Mickie Elmore, Kevin Baker and Alan
Berenbrock. Questions in italics, answers in regular font.
1. We in ABEQ have been asking for details for the last two years as to specific designs
of the detention ponds, starting with our letter of July 24, 1999. Is the Stormwater
Management Plan finalized? Our copy is a preliminary final one dated April, 2001, and
is of a conceptual nature.
The document is not finished. Completed, as is, in April 2001. It is a work in progress.
Randleman rules have been adopted. All BMP structures are conceptual in nature.
2. Is there a grading plan for the new runway sorting facility, taxiways, etc.? Does it
include any of the detention ponds, particularly the F series? We note the precision of the
1,174, 174,582 cubic yards of fill discharged into jurisdictional wetlands, thus believe grading
plans do exist. The F series structures are major structures and are of such importance
that they justify detailed planning, and without this type of planning we cannot analyze
them.
Agree that F series ponds are important. None. Have been designed. Fill numbers are
preliminary and subject to change. New grading plan due in October. A copy will be sent
to ABEQ when it is completed.
3. Do you have specific plans for the F series (a) limiting flow to the existing wetlands,
thus increasing detention time, (b) providing sheet flow through the wetlands, (c) limiting
velocity to one or two feet per second through the wetlands?
We have guidelines but not specific plans. The space for ponds is very tight. The
document was written to meet or exceed current city, state, county guidelines.-
4. Will the ou flow from the larger storms, like the 10 and 100 year, also flow through the
existing wetlands? Yes.
5. How do you propose to remove soluble pollutants, lead, zinc, rubber, and oil and
grease in the runofffrom the impervious areas? ABEQ s position is that the removal of
TSS is not enough, since this is a critical area draining immediately into a municipal
water supply, and all pollutants must be addressed.
Don't. Not required by state. State actually requires 85% removal of TSS.
6 Do you have a policy of complying with criteria in the Guilford County Watershed
Protection Manual (January 1997)?
Yes. County requirements have been adopted into Master Plan. Watershed plans can be
submitted to us for review. They always meet or exceed requirements be it watershed or
building plans.
w . ?
7. Have you seen comments over the last year or so by ABEQ and its members directed to
the NC Division of Water Quality? These are a matter of public record, but in cae you
have not, we are attaching copies.
Have seen the comments they work closely with NCDENR and have taken any
comments into consideration.
8. It is apparent that there has been an effort to avoid a NC Dam Safety Permit. As will
be noted in the attached comments, the structures are lacking in storage capacity, which
compromises water quality, and fail to meet Guilford County criteria. Are we correct in
this? It is our view that the runofffrom 240 acres of impervious area is so major that a
dam safety permit will be necessary, particularly when the proper storage is provided.
Aware of Dam Safety Laws -
- Instead of 1 pond they have broken it down into 3 ponds.
- They would rather have several non-high hazard dams than 1 high hazard dam.
- There is a document in master plan that asks designer of pond "is a dam safety
permit required" if so it is obtained.
- Ponds might be use specific (i.e. runoff from plane maintenance areas goes to one
pond, runways go to another pond.
- -Airport is in the process of obtaining a NPDES permit.
Plans due in October will have pond design information.
NPDES permits will include soluble pollutants and give corrective activities should
pollutant levels exceed those allowed by the permit.