20081199 Ver 2_Approval Letter_20090617

A ?
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins
Governor Director
June 17, 2009
Ms. Lori Hurd
c/o Girl Scouts Hornets Nest Council
7007 Idlewild Road
Charlotte, NC 28212
Re: Girl Scout Environmental Academy At Oak Springs, Mecklenburg County
DWQ #20081199, Vera 2; USACE Action ID. No. 200800858
Ut to Cedar Creek [030301; 28-29-(2), C, NSW]
APPROVAL of 401 Water Quality Certification with Additional Conditions
Dear Ms. Hurd:
Dee Freeman
Secretary
Attached hereto is a copy of Certification No. 3801 issued to Ms. Lori Hurd and the Girl Scouts
Hornets Nest Council, dated June 17, 2009. In addition, you should get any other federal, state
or local permits before you go ahead with your project including (but not limited to) Solid
Waste, Sediment and Erosion Control, Stormwater, Dam Safety, Non-discharge and Water
Supply Watershed regulations.
If we can be of further assistance, do not hesitate to contact us.
Sinc ly,
leen H. Sullins
CHS/cbk/ijm
Attachments: Certificate of Completion
NC DWQ 401 WQC Summary of Permitted Impacts and Mitigation Requirements
Predictability Study Protocol for Sampling Reference Impoundments (NCDWQ,
March 12, 2008).
cc: Becky Fox, EPA Region 4, 1307 Firefly Road, Whittier, NC 28789
U.S. Army Corps of Engineers, Asheville Regulatory Field Office, Wilmington District
Alan Johnson, DWQ Mooresville Regional Office
DLR Mooresville Regional Office
File Copy
Michael T. Brame, ECS, LLP, 4811 Koger Boulevard, Greensboro, NC 27455
Filename: 081199Ver2GirlScoutsEnvironmentalAcademyProposedLake(Iredell)401_IC
401 Oversight/Express Review Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 2321 Crabtree Blvd., Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone]
Internet: http://h2o.enr.state.nc.uslncwetlands/
North Carohna
Natmallrf
An Equal Opportunity 1 Affirmative Action Employer
Ms. Lori Hurd and the Girl Scouts Hornets Nest Council
Page 2 of 6
June 17, 2009
NORTH CAROLINA 401 WATER QUALITY CERTIFICATION
THIS CERTIFICATION is issued in conformity with the requirements of Section 401 Public
Laws 92-500 and 95-217 of the United States and subject to the North Carolina Division of Water
Quality (DWQ) Regulations in 15 NCAC 2H, Section .0500 to Ms. Lori Hurd and the Girl Scouts
Hornets Nest Council to fill or otherwise impact 0.0104 acres of 404/wetland, 3,993 linear feet of
perennial stream (323 linear feet perennial stream fill for dam, 115 linear feet of perennial stream
impact for the spillway, and 3,555 linear feet of perennial stream flooding), and 1,268 linear feet of
intermittent stream flooding, to construct the Girl Scout Environmental Leadership Center and
recreational lake at the referenced site. The site is located off Hay Meadow Lane and Fairmont
Road, north of Statesville, in Iredell County, North Carolina, pursuant to an application dated May
7, 2009 (received by the DWQ on May 8, 2009, and Public Notice issued by the U.S. Army Corps
of Engineers on September 30, 2008 (received by the DWQ on September 30, 2008).
The application and supporting documentation provides adequate assurance that the proposed
work will not result in a violation of applicable Water Quality Standards and discharge
guidelines. Therefore, the State of North Carolina certifies that this activity will not violate the
applicable portions of Sections 301, 302, 303, 306, 307 of PL 92-500 and PL 95-217 if
conducted in accordance with the application, the supporting documentation, and conditions
hereinafter set forth.
This approval is only valid for the purpose and design submitted in the application materials and
as described in the Public Notice. If the project is changed, prior to notification a new
application for a new Certification is required. If the property is sold, the new owner must be
given a copy of the Certification and approval letter and is thereby responsible for complying
with all conditions of this Certification. Any new owner must notify the Division and request the
Certification be issued in their name. Should wetland or stream fill be requested in the future,
additional compensatory mitigation may be required as described in 15A NCAC 2H.0506 (h) (6)
and (7). If any plan revisions from the approved site plan result in a change in stream or wetland
impact or an increase in impervious surfaces, the DWQ shall be notified in writing and a new
application for 401 Certification may be required. For this approval to be valid, compliance with
the conditions listed below is required.
Conditions of Certification:
1. Impacts Approved
The following impacts are hereby approved as long as all of the other specific and
general conditions of this Certification (or Isolated Wetland Permit) are met. No other
impacts are approved including incidental impacts:
Type of Impact Amount Approved Units Plan Location or Reference
404/Wetland 0.0104 (acres) Application materials and
USACE Public Notice
Stream - perennial 3,993 [(linear feet) 323 linear feet perennial stream Application materials and
fill for dam, 115 linear feet of perennial stream USACE Public Notice
impact for the spillway, and 3,555 linear feet of
perennial stream flooding]
Ms. Lori Hurd and the Girl Scouts Hornets Nest Council
Page 3 of 6
June 17, 2009
Stream - intermittent 1,268 (linear feet) - flooding Application materials and
USACE Public Notice
Sediment and Erosion Control:
2. Erosion and sediment control practices must be in full compliance with all specifications
governing the proper design, installation and operation and maintenance of such Best
Management Practices in order to protect surface waters standards:
a. The erosion and sediment control measures for the project must be designed,
installed, operated, and maintained in accordance with the most recent version of the
North Carolina Sediment and Erosion Control Planning and Design Manual.
b. The design, installation, operation, and maintenance of the sediment and
erosion control measures must be such that they equal, or exceed, the requirements
specified in the most recent version of the North Carolina Sediment and Erosion
Control Manual. The devices shall be maintained on all construction sites, borrow
sites, and waste pile (spoil) projects, including contractor-owned or leased borrow
pits associated with the project.
c. Sufficient materials required for stabilization and/or repair of erosion control
measures and stormwater routing and treatment shall be on site at all times.
3. No waste, spoil, solids, or fill of any kind shall occur in wetlands, waters, or riparian areas
beyond the footprint of the impacts depicted in the 404/401 Permit Application. All
construction activities, including the design, installation, operation, and maintenance of
sediment and erosion control Best Management Practices, shall be performed so that no
violations of state water quality standards, statutes, or rules occur;
4. Sediment and erosion control measures shall not be placed in wetlands or waters without prior
approval from the Division. If placement of sediment and erosion control devices in wetlands
and waters is unavoidable, design and placement of temporary erosion control measures shall
not be conducted in a manner that may result in dis-equilibrium of wetlands or stream beds or
banks, adjacent to or upstream and down stream of the above structures. All sediment and
erosion control devices shall be removed and the natural grade restored within two (2) months
of the date that the Division of Land Resources or locally delegated program has released the
project;
5. Protective Fencing - The outside buffer, wetland or water boundary and along the construction
corridor within these boundaries approved under this authorization shall be clearly marked
with orange warning fencing (or similar high visibility material) for the areas that have been
approved to infringe within the buffer, wetland or water prior to any land disturbing activities
to ensure compliance with 15A NCAC 2B .0259;
Continuing Compliance:
6. Ms. Lori Hurd and the Girl Scouts Hornets Nest Council shall conduct construction activities
in a manner consistent with State water quality standards (including any requirements
resulting from compliance with section 303(d) of the Clean Water Act) and any other
appropriate requirements of State law and federal law. If the Division determines that such
standards or laws are not being met (including the failure to sustain a designated or achieved
Ms. Lori Hurd and the Girl Scouts Hornets Nest Council
Page 4 of 6
June 17, 2009
use) or that State or federal law is being violated, or that further conditions are necessary to
assure compliance, the Division may reevaluate and modify this Certification to include
conditions appropriate to assure compliance with such standards and requirements in
accordance with 15A NCAC 2H.0507(d). Before modifying the Certification, the Division
shall notify Ms. Lori Hurd and the Girl Scouts Hornets Nest Council and the US Army Corps
of Engineers, provide public notice in accordance with 15A NCAC 211.0503 and provide
opportunity for public hearing in accordance with 15A NCAC 2H.0504. Any new or revised
conditions shall be provided to Ms. Lori Hurd and the Girl Scouts Hornets Nest Council in
writing, shall be provided to the United States Army Corps of Engineers for reference in any
Permit issued pursuant to Section 404 of the Clean Water Act, and shall also become
conditions of the 404 Permit for the project;
Deed Notifications:
7. Deed notifications or similar mechanisms shall be placed on all lots with remaining
jurisdictional wetlands and waters or areas within 50 feet of all streams and ponds. These
mechanisms shall be put in place within 30 days of the date of issuance of the
401 Certification letter or the issuance of the 404 Permit (whichever is later). A sample deed
notification format can be downloaded from the 401/Wetlands Unit web site at
http://h2o.enr.state.ne.us/ncwetlands DWQ shall be sent copies of all deed restrictions
applied to these lots;
8. Construction Stormwater Permit NCG010000
Upon the approval of an Erosion and Sedimentation Control Plan issued by the Division of
Land Resources (DLR) or a DLR delegated local erosion and sedimentation control program,
an NPDES General stormwater permit (NCGO10000) administered by DWQ is automatically
issued to the project. This General Permit allows stormwater to be discharged during land
disturbing construction activities as stipulated by conditions in the permit. If your project is
covered by this permit [applicable to construction projects that disturb one (1) or more acres],
full compliance with permit conditions including the sedimentation control plan, self-
monitoring, record keeping and reporting requirements are required. A copy of this permit
and monitoring report forms may be found at
http: //h2o. enr. state. nc. us/su/Forms Documents. htm. ;
9. The minimum water release plan for the proposed dam must be approved in writing by this
Office before the approved impacts may occur. The plan must include a written explanation
of the specific discharge rate and mechanism to provide.for each required release. The plan
must also include any design specifications, details and calculations to show that the release
shall be achieved in the given conditions. The plan shall also include monitoring that ensures
compliance. The plan and any associated facilities, once approved, must be in place and
implemented upon the completion of the dam.
10. The impoundment discharge should be monitored to ensure thermal impacts to
waters will not exceed the temperature standard for piedmont streams. Unless
otherwise stipulated by the Division of Water Quality, discharge water temperatures
should be routinely monitored and compared to inflow water temperatures to ensure
Ms. Lori Hurd and the Girl Scouts Hornets Nest Council
Page 5 of 6
June 17, 2009
compliance.
11. The discharge should be aerated to enhance dissolved oxygen levels.
12. Littoral shelves and native vegetation should be provided along the shoreline for
stability, safety, shading and habitat.
13. The use of motorized equipment as well as fertilizers and other chemicals in the
lake and around the shoreline should be strictly controlled so as not to cause direct or
ancillary pollutant issues downstream.
14. An impoundment sampling schedule and methodology must be finalized before the proposed
impacts may occur. This Office recommends utilizing the attached guidance document
Predictability Study Protocol for Sampling Reference Impoundments (NCDWQ, March 12,
2008).
15. Final design details for the dam and impoundment shall be submitted to DWQ for approval
in writing before the proposed impacts may occur. The final plan shall include a discussion
of how water quality standards will be monitored and maintained within the impoundment.
The final plan shall also include the structural design drawings and details for the dam,
including the plan and profile views illustrating the height, toe, materials, spillway, as well as
the operation and maintenance plan.
Mitigation:
16. Compensatory Mitigation Using the Ecosystem Enhancement Program (EEP)
Mitigation must be provided for the proposed impacts as specified in the table below. We
understand that you wish to make a payment to the Wetlands Restoration Fund administered
by the NC Ecosystem Enhancement Program (EEP) to meet this mitigation requirement.
This has been determined by the DWQ to be a suitable method to meet the mitigation
requirement. Until the EEP receives and clears your check (made payable to: DENR -
Ecosystem Enhancement Program Office), no impacts specified in this Authorization
Certificate shall occur. The EEP should be contacted at [phone] if you have any
questions concerning payment into a restoration fund. You have 60 days from the date of
this approval to make this payment. For accounting purposes, this Authorization
Certificate authorizes payment into the Wetlands Restoration Fund to meet the
following compensatory mitigation requirement:
Type of Impact Compensatory Mitigation Required River and Sub-basin Number
Stream (perennial) 408 (linear feet) Yadkin/03040102
17. Certificate of Completion
Upon completion of all work approved within the 401 Water Quality Certification or
applicable Buffer Rules, and any subsequent modifications, the applicant is required to return
the attached certificate of completion to the 401 Oversight/Express Review Permitting Unit,
Ms. Lori Hurd and the Girl Scouts Hornets Nest Council
Page 6 of 6
June 17, 2009
North Carolina Division of Water Quality, 1650 Mail Service Center, Raleigh, NC, 27699-
1650.
Also, this approval to proceed with your proposed impacts or to conduct impacts to waters
as depicted in your application shall expire upon expiration of the 404 Permit.
If this Certification is unacceptable to you, you have the right to an adjudicatory hearing upon
written request within sixty (60) days following receipt of this Certification. This request must be
in the form of a written petition conforming to Chapter 150B of the North Carolina General
Statutes and filed with the Office of Administrative Hearings, 6714 Mail Service Center,
Raleigh, N.C. 27699-6714. If modifications are made to an original Certification, you have the
right to an adjudicatory hearing on the modifications upon written request within sixty (60) days
following receipt of the Certification. Unless such demands are made, this Certification shall be
final and binding.
This the 17`h day of June 20
DIVIS N OF WAT R Q ITY
oleen H. Sullins
CHS/cbk/ijm
3801
w A rF9P?
0 r
Michael F. Easley, Governor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Coleen H. Sullins, Director
Division of Water Quality
North Carolina Division of Water Quality
401 Water Quality Certification
Summary of Permitted Impacts and Mitigation Requirements
In accordance with 15A NCAC 2H.0500, Ms. Lori Hurd and the Girl Scouts Hornets Nest Council, have
permission as outlined below to fill or otherwise impact 0.0104 acres of 404/wetland, 3,993 linear feet of perennial
stream (323 linear feet perennial stream fill for dam, 115 linear feet of perennial stream impact for the spillway,
and 3,555 linear feet of perennial stream flooding), and 1,268 linear feet of intermittent stream flooding, to
construct the Girl Scout Environmental Leadership Center and recreational lake at the referenced site, which is
located off Hay Meadow Lane and Fairmont Road, north of Statesville, in Iredell County, North Carolina. All
activities associated with these authorized impacts must be conducted with the conditions listed in the attached
Permit transmittal letter. THIS CERTIFICATION IS NOT VALID WITHOUT THE ATTACHMENTS.
COMPENSATORY MITIGATION REQUIREMENTS, ECOSYSTEM ENHANCEMENT PROGRAM
NC EEP NAME: Girl Scouts Environmental Academy
DWQ PROJECT #: 20081199, Ver. 2
LOCATION: Near Statesville
COUNTY Iredell
BASIN/ SUB BASIN Yadkin/03040102
As required by 15A NCAC 2H.0500, and the conditions of this Certification, you are required to compensate for
the above mitigable impacts through the restoration, creation, enhancement or preservation of wetlands, surface
waters and riparian buffers as outlined below prior to conducting any activities that impact or degrade the waters of
the state.
Note: Acreage requirements proposed to be mitigated through the Ecosystem Enhancement Program must be
rounded to one-quarter acre increments and linear foot requirements must be rounded up to the nearest
foot according to 15 2R.0503(b).
Impacts Mitigation
408 Linear Feet of Perennial Stream 408 Linear Feet of Perennial Stream
One of the options you have available to satisfy the compensatory mitigation requirement is through the payment of
a fee to the Wetlands Restoration Fund per NCAC 2R.0503. If you choose this option, please sign this form and
mail the form along with a copy of your 401 Certification or Buffer Approval to the Ecosystem Enhancement
Program at the address below. An invoice for the appropriate amount of payment will be sent to you upon receipt
of this form. PLEASE NOTE, THE ABOVE IMPACTS ARE NOT AUTHORIZED UNTIL YOU RECEIVE
NOTIFICATION THAT YOUR PAYMENT HAS BEEN PROCESSED BY THE ECOSYTEM ENHANCMENT
PROGRAM.
Signature
Date
ECOSYSTEM ENHANCEMENT PROGRAM
1652 Mail Service Center
RALEIGH, N.C. 27699-1652
[phone]
Filename: 081199Ver2GirlScoutsEnvironmentalAcademyProposedLake(Iredell)401 _IC-EEP
Noo;etttCarolma
401 Oversight/Express Review Permitting Unit !ltltCRllj?
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone [phone] / Fax [phone]
Internet: http://www.ncwaterquality.org
An Equal Opportunity/Affirmative Action Employer - 50% Recycled/ 10% Post Consumer Paper
Predictability Study Protocol for
Sampling Reference Impoundments
Prepared by North Carolina Division of Water Quality,
Wetlands and Stormwater Branch
March 12, 2008
Background
NC has a regulatory Antidegradation Policy (15A NCAC 02B .0201) that states that it is
the "policy of the Environmental Management Commission to maintain, protect, and
enhance water quality within the State of North Carolina". Activities that may cause a
degradation of water quality should be avoided unless the applicant can show that denial
of the proposed project will inhibit "important social and economic development".
The NC Division of Water Quality receives requests to impound streams and rivers to
create amenity lakes, particularly in housing developments. These reservoirs do not serve
a great public need, such as serving as a water supply, and often do not provide
"important social and economic development" sufficient to over-ride the primary policy
of the state to maintain and protect water quality. Lakes are not naturally occurring in the
majority of the state and impoundments often result in a degradation of water quality,
mainly due to a high acceleration of the eutrophication process, so any impoundment
should come under additional scrutiny. Changing the character of a waterbody from a
lotic (flowing) to a lentic (impounded) system may result in:
• higher sensitivity to nutrient enrichment, with levels that may not cause issues in a
lentic system leading to overgrowths of algae and nuisance aquatic plants in a
lotic system;
• increased nuisance growths, which can degrade water quality as reflected in
dissolved oxygen concentrations, pH, water temperature, chlorophyll-a, and total
dissolved gases, and may result in the waterbody no longer meeting NC numerical
water quality standards (refer to 15A NCAC 2B .0200);
• degradation of water quality downstream of the impoundment (e.g., instream
dissolved oxygen and/or temperature can be increased or decreased to undesirable
levels, depending on the type of release; concentrations of ammonia and TKN
may be increased, particularly in the case of bottom releases);
• negative impacts on channel morphology of the downstream reach, including a
higher susceptibility to vertical downcutting and lateral (bank) erosion, resulting
in channel incision, streambank instability, and a long-term imbalance of the
sediment and flow regime;
• deleterious impacts on instream fauna downstream of the impoundment due to the
cumulative effects of all the above factors.
The rate of impoundment requests and the high potential for impoundments to degrade
water quality and to violate water quality standards has led to the need for additional
information from the applicant for use by DWQ staff in the permitting process.
Protocol for Sampling Reference Impoundments, March 12, 2008
Page 1 of 5
Therefore, it is incumbent on the permit applicant to show that a proposed impoundment
project is unlikely to cause a degradation in water quality within the affected reach,
which includes not only the impounded section of stream but also upstream and
downstream of the proposed project. The guidelines outlined in this document are to be
used by applicants to collect appropriate water quality data to support their assertion that
the proposed project will not cause degradation of water quality.
Introduction
In order to show that the proposed project will not cause a degradation of water quality
within the affected reach, the applicant shall collect appropriate water quality data in a
minimum of two existing impoundments that are similar to the project being proposed.
These data will be assessed by DWQ to ensure that numerical water quality standards are
not being exceeded, and also to determine if a significant change in water quality exists
by comparing data from the upstream and downstream reaches.
The applicant shall use the following guidelines to develop a written study plan and
sampling schedule, which will be submitted to DWQ staff for approval at least 30 days in
advance of the proposed start of monitoring.
Site Selection
A minimum of two comparable impoundments will be selected by the applicant for
monitoring. It is unlikely that completely comparable impoundments will exist, and each
proposed project will likely have slightly different concerns; the following criteria are
shown in relative order of importance and shall be used to select the most comparable
sites. The applicant shall specify why the proposed sampling sites meet these criteria,
and if not, what impact(s) that may have on the interpretation of the resulting data, and
the relative importance of the impact(s).
The study sites shall be:
• Within the same 8-digit hydrologic unit (HUC) as defined by the USGS
(http://water.usms.gov/GIS/huc.html);
• Within the same Level IV ecoregion
(ftp://fti).epa.gov/wed/ecore iog ns/nc sc/nc eco.pdf) preferred;
• Of a comparable design, particularly in terms of type of release (e.g., epilimnion
or hypolimnion)
• Land use similar to what is anticipated in the built-out area surrounding and
upstream of the proposed project (cumulative impacts from housing development,
etc. taken into account), and has a comparable vegetated (woody) buffer (if
present);
• Of comparable character in terms of size, primarily surface area, though mean
depth and volume should also be taken into consideration;
• The impounded stream will be of the same or similar stream order;
• Similar drainage area of the watershed;
• Have a similar retention time, if known.
Protocol for Sampling Reference Impoundments, March 12, 2008
Page 2 of 5
At the applicant's discretion, additional data may
be collected from nearby (within the same Level
IV ecoregion) natural lakes (where available, see
below for list) to show that conditions within the
study impoundments are not significantly
different from those found under natural
conditions with minimal impacts.
Sampling schedule
A minimum total of ten sample sets should be
collected. Sampling and measurements should
occur during the "growing season", defined as the
period from May 1 through September 30. All
sampling and measurements should be performed
during daylight hours. Data may be collected:
every other week during the growing
season within a single calendar year, or
collected monthly during the growing season over two consecutive calendar
years.
Sampling stations
For each impoundment sampled, four to six specific sampling stations should be
identified as follows:
• one station on the stream located in a flowing (lotic) reach upstream of the
reference impoundment;
• two to four stations (depending on size and heterogeneity of the system under
study), evenly spaced across the centerline of the impoundment (i.e., bank to bank
transect) (lentic);
• one station on the project stream located in a flowing (lotic) reach downstream
(within 500 feet) of the reference impoundment.
Locations of all sampling stations should be georeferenced in the field using NAD83
datum.
Water Quality Indicators
The indicators to be measured include water temperature, dissolved oxygen saturation,
dissolved oxygen concentration, pH, specific conductance, Secchi depth transparency,
total suspended residue, turbidity, nutrients (total phosphorus, total Kjeldahl nitrogen,
ammonia [NH3], nitrate + nitrite [N02+NO31), chlorophyll-a(corrected for pheophytin),
and fecal coliform. Depth to bottom should also be recorded for the two to four lentic
stations (i.e., within the impoundment).
Table 1: Natural lakes in NC
Lei
N'ainez, . -
YRver Balm . ,
Alligator Lake Pas uotank
Bay Tree Lake Cape Fear
Catfish Lake White Oak
Ellis Lake Neuse
Great Lake White Oak
Jones Lake Cape Fear
Lake Mattamuskeet Tar-Pamlico
Lake Phelps Pas uotank
Lake Waccamaw Lumber
Pun go Lake Tar-Pamlico
Salters Lake Cape Fear
Singletary Lake Cape Fear
Swan Creek Lake Pas uotank
Protocol for Sampling Reference Impoundments, March 12, 2008
Page 3 of 5
Sampling methods
All sampling, field measurements, and QA/QC procedures should conform to the
methods outlined in the DWQ Intensive Survey Unit (ISU) Physical and Chemical
Monitoring Standard Operating Procedure (SOP), available online at
htti):Hh2o.enr.state.nc.us/esb/isu.html. Two different sampling methods will be used,
depending on whether the station is lotic (upstream and downstream reaches) or lentic
(within the impoundment), as described below and summarized in Table 2:
• Lotic stations: Field measurements (temperature, DO, pH, specific conductance)
will be taken in situ at a depth of approximately 0.1m below the surface. Water
samples for nutrients, total suspended residue, turbidity, and fecal coliform are to
be taken as grab samples at a depth of approximately 0.1 m below the surface. All
measurements and samples should be taken in a flowing, well-mixed area of the
stream, generally at or near the thalweg.
• Lentic stations: Field measurements (temperature, DO, pH, specific conductance)
will be taken at each station just below the surface (depth of approximately 0.1m),
and at 1 m intervals to the lake bottom. Secchi depth transparency should be taken
at each sampling location. Fecal coliform samples shall be collected as grab
samples at a depth of approximately 0.1m below the surface. Samples for
nutrients, total suspended residue, chlorophyll a, and turbidity shall be taken as
spatial composites of the photic zone, defined as twice the Secchi depth. The
preferred method of composite sampling is to use a LabLine (see ISU SOP for
description) or similar type sampler that allows continuous sampling as it is
lowered and raised throughout the photic zone. Less desirable but acceptable is
the use of a Van Dorn or similar sampler to collect multiple grab samples at
regular intervals throughout the photic zone, and composite them before
distributing into sample bottles.
Table 2: Summary of water quality indicators to be measured. All depths are measured from the water
surface.
Parameter Upstream of
impoundment
(1 station) Impoundment Cross section
(2-4 stations) Downstream of
impoundment
(1 station)
Field measurements Yes, 0.1 m only 0.1 m and every meter
to bottom Yes, 0.1 m only
Depth to bottom N/A Yes N/A
Secchi transparency N/A Yes N/A
Fecal coliform Grab Grab Grab
Total suspended
residue Grab Photic zone composite Grab
Turbidity Grab Photic zone composite Grab
Nutrients Grab Photic zone composite Grab
Chlorophyll a N/A Photic zone composite N/A
Protocol for Sampling Reference Impoundments, March 12, 2008
Page 4 of 5
Analytical methods
All measurements and analyses shall be performed by a laboratory with a current North
Carolina Wastewater Laboratory Certification for the parameters of interest (including
field parameters). A list of certified laboratories is available at
http://h2o.enr.state.nc.us/lab/cert.htm. All sample handling, preservation, and analysis
should be performed using approved. methods (see
http://h2o.enr.state.nc.us/lab/inorgparam.htm).
Reporting
The applicant should provide an interpretive report summarizing all results and findings
to DWQ 401 Oversight Unit for review. Results from all samples and measurements
should also be provided in electronic form, e.g., Excel spreadsheet or delimited text file.
DWQ will review for completeness, comparison of raw values to appropriate surface
water quality standards included in the NC Administrative Code (15A NCAC .0200, see
http://h2o.enr.state.nc.us/admin/rules/codes statutes.htm), and significant differences
between lotic sites.
Protocol for Sampling Reference Impoundments, March 12, 2008
Page 5 of 5