20061302 Ver 2_Application_20080424

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~1RTIFEX inc
ENVIRONMENTAL DESIGN
2363 Blake Street, Suite 202
Denver, CO 80205
[phone] phone
[phone] /ax
www.ortl jexed.com
April 23, 2008
OI.P-~~D2 V~
North Carolina Department of Environment and Natural Resources
Division of Water Quality /401 Wetlands Unit
1650 Mail Service Center
Raleigh, NC 27699-1650
RE: North Carolina Museum of Art Expansion
Dear Sir or Madam:
Please find the attached permit application and supporting materials for the 401 Water Quality
Cert~cation Permit for the North Carolina Museum of Art Expansion.
The North Carolina Museum of Art is expanding the existing facilities at its location in Raleigh, North
Carolina. The existing museum requires a number of upgrades to meet current building requirements.
At the same time, the museum has outgrown the existing facility and is planning improvements to the
existing buildings and construction of a new gallery wing.
Stormwater for the Museum Expansion development will be managed through the use of several grass
swales, a vegetated Swale floodway reach, and a wetland marsh adjacent to the existing pond.
Improvements to the pond configuration and outlet structure will increase the detention capacity of the
pond. A number of water quality improvements will be made to realize the full water quality benefits of a
combined wetpond with a wetland marsh, through rehabilitation of the existing infrastructure.
We have provided the following:
• Five (5) copies of the permit application and supporting documents;
• Five (5) copies of the 11x17 construction drawings;
• Two (2) copies of the full size construction drawings; and
• Electronic submittal on CD.
.Also enGosed are the buffer determination for the referenced blueline stream and existing stormwater
pond (both determined "not subject"), which was received after publication of the bound report.
Permit fees have been submitted where required, via electronic payment.
Please feel free to contact this office for further information at any time.
Sincerely,
Stephen H. Blake, P.E.
Director of Engineering
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A RTIFEX
ENVIRONMENTAL DESIGN
2363 Blake Street, Suite 202
Denver, CO 80205
[phone] phone
[phone] fax
www.artiJexed.com
April 23, 2008
NCDENR Division of Water Quality
Stormwater Permitting Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
919-733-5083
KS ,
inc
RE: North Carolina Museum of Art Expansion
Dear Sir or Madam:
Please find the attached permit application and supporting materials for the Stormwater Permit for the
North Carolina Museum of Art Expansion.
The North Carolina Museum of Art is expanding the existing facilities at its location in Raleigh, North
Carolina. The existing museum requires a number of upgrades to meet current building requirements.
At the same time, the museum has outgrown the existing facility and is planning improvements to the
existing buildings and construction of a new gallery wing.
Stormwater for the Museum Expansion development will be managed through the use of several grass
swales, a vegetated swale floodway reach, and a wetland marsh adjacent to the existing pond.
Improvements to the pond configuration and outlet structure will increase the detention capacity of the
pond. A number of water quality improvements will be made to realize the full water quality benefits of a
combined wetpond with a wetland marsh, through rehabilitation of the existing infrastructure.
We have provided the following:
• Three (3) copies of the permit application and supporting documents;
• Three (3) copies of the 11 x17 construction drawings; and
• Electronic submittal on CD.
Also enclosed are the buffer determination for the referenced blueline stream and existing stormwater
pond (both determined "not subject"), which was received after publication of the bound report.
Permit fees have been submitted where required, via electronic payment.
Please feel free to contact this office for further information at any time.
Sincerely,
~.~,,L... ~ ~._
Stephen H. Blake, P.E.
Director of Engineering

D
~~
Office Use Only: Form Version Match OS
USACE Action ID No. DWQ No. ~ to ~ 3 O ~. y 2
iii any parucuiar item is not appucaoie w uus project, please enter "Not Applicable" or "N/A".)
I. Processing
1. Check all of the approval(s) requested for this project:
® Section 404 Permit ® Riparian or Watershed Buffer Rules
^ Section 10 Permit ^ Isolated Wetland Permit from DWQ
® 40I Water Quality Certification ^ Express 401 Water Quality Certification
2. Nationwide, Regional or General Permit Number(s) Requested: #3, #39, #43
3. If this notification is solely a courtesy copy because written approval for the 401 Certification
is not required, check here: ^
4. If payment into the North Carolina Ecosystem Enhancement Program (NCEEP} is proposed
for mitigation of impacts, attach the acceptance letter from NCEEP, complete section VIII,
and check here: ^
5. If your project is located in any of North Cazolina's twenty coastal counties (listed on page
4), and the project is within a North Carolina Division of Coastal Management Area of
Environmental Concern (see the top of page 2 for further details}, check here
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II. Applicant Information , ,S -- ~ ~ j
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Owner/Applicant Information

Name: North Carolina Museum of Art ~ c~TC'LtEB - ~a, , . -_ :- , ,;,, ~
Mailing Address:2110 Blue Ridae Roa , Raleigh, NC. 27607 'rG'E. e ~.~~» Fr~~ s~~ ~?~?"'N`a; t=~' '~'~.r~`:~'
Telephone Number:___(919) 839-6262 Fax Number: [phone]
E-mail Address: d~ottlieb(a,ncmamail.dcr.state.nc.us
2. AgenUConsultant Information (A signed and dated copy of the Agent Authorization letter
must be attached if the Agent has signatory authority for the owner/applicant.}
Name: Stephen H. Blake
Company Affiliation: Artifex Environmental Design
Mailing Address: 2363 Blake Street, Suite 202, Denver, CO. 80205
Telephone Number: [phone] Fax Number: [phone]
E-mail Address: steve.blake(a~artifexed.com
III. Project Information
Attach a vicinity map clearly showing the location of the properly with respect to local
landmarks such as towns, rivers, and roads. Also provide a detailed site plan showing property
boundaries and development plans in relation to surrounding properties. Both the vicinity map
u~r~a itiii2oos
Page 5 of 12

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and site plan must include a scale and north arrow. The specific footprints of all buildings,
impervious surfaces, or other facilities must be included. Tf possible, the maps and plans should
include the appropriate USGS Topographic Quad Map and NRCS Soil Survey with the property
boundaries outlined. Plan drawings, or other maps may be included at the applicant's discretion,
so long as the property is cleazly defined. For administrative and distribution purposes, the
USAGE requires information to be submitted on sheets no larger than 11 by 17-inch format;
however, DWQ may accept paperwork of any size. DWQ prefers full-size construction
drawings rather than a sequential sheet version of the full-size plans. If full-size plans are
reduced to a small scale such that the fmal version is illegible, the applicant will be informed that
the project has been placed on hold until decipherable maps are provided.
1. Name of project: North Carolina Museum of Art -Museum Expansion Proiect
2. T.LP. Project Number or State Project Number {NCDOT Only):
3. Property Identification Number (Tax FIN):
4. Location
County: Wake Nearest Town: Raleigh
Subdivision name (include phase/lot number):
Directions to site (include road numbers/names, landmarks, etc.): From Interstate 440 head
-west on Raleigh -Chanel Hill Expv/ Wade Ave Take the Blue Ridge Road exit Turn n~ht
at Blue Ride Road.
5. Site coordinates (For lineaz projects, such as a road or utility line, attach a sheet that
sepazately lists the coordinates for each crossing of a distinct waterbody.)
Decimal Degrees (6 digits minimum): 3~° 48' 36"" °N -78° 42" 20"' °W
6. Properly size (acres): 165
7. Name of nearest receiving body of water: House Creek
8. River Basin: Neuse River Basin
(Note -this must be one of North Carolina's seventeen designated major river basins. The
River Basin map is available at http://h2o.enr.state.nc.us/admin/mans/.)
9. Describe the existing conditions on the site and general land use in the vicinity of the project
at the time of this application: The existing site consists of the museum core maintenance
facility (warehouse and building) roadway narking-structures and small miscellaneous
structures. There is also a Museum Park and Preserve a riparian corridor and a museum
Green that includes trees, Qazdens and landscaping
10. Describe the overall project in detail, including the type of equipment to be used: The
proiect consists of expansion to the existing museum building construction of new exhibition
space, and revised site nazkinQ and roadway configuration There will also be improvements
Updated 11/I/2005
Page 6 of 12

to the existing pond including water quality terraces, bioretention, and created stormwater
marsh features.
11. Explain the purpose of the proposed work: The museum was designed in the late 1970's
and requires upgrades to meet current building requirements. Also, the museum has
outgrown the existin facility and needs to expand Rehabilitation of the pond and the
adjacent Swale will improve stormwater management and water quality of stonnwater runoff'
from existing_and proposed surfaces.
IV. Prior Project History
If jurisdictional determinations and/or permits have been requested and/or obtained for this
project (including all prior phases of the same subdivision) in the past, please explain. Include
the USACE Action ID Number, DWQ Project Number, application date, and date permits and
certifications were issued or withdrawn. Provide photocopies of previously issued permits,
certifications or other useful information. Describe previously approved wetland, stream and
buffer impacts, along with associated mitigation (where applicable). If this is a NCDOT project,
list and describe permits issued for prior segments of the same T.LP. project, along with
construction schedules. Stream and water body buffer determinations have been requested for the
site. Documentation is provided in the appendix. A preliminary review has been requested by
USACE to determine jurisdictional issues. Erosion and sediment control permits have been
obtained from NCDENR division of land resources, which are also included in the appendix.
V. Future Project Plans
Are any future permit requests anticipated for this project? If so, describe the anticipated work,
and provide justification for the exclusion of this work from the current application.
The North Carolina Water Qualii~ Improvement Project, funded through a Brant from Clean
Water Management Trust Fund, will be positioned on the upper banks and azeas adjacent to the
pond. The outfall will be reconfigured at this time, along with a number of related modifications
to existing- storm sewers. This work is currently in an early designn stage, and will be desi n
accommodate the grades established in the construction activity that is the subject of this permit
application.
VI. Proposed Impacts to Waters of the United StateslWaters of the State
It is the applicant's (or agent's) responsibility to determine, delineate and map all impacts to
wetlands, open water, and stream channels associated with the project. Each impact must be
listed separately in the tables below (e.g., culvert installation should be listed sepazately from
riprap dissipater pads). Be sure to indicate if an impact is temporary. All proposed impacts,
permanent and temporary, must be listed, and must be labeled and clearly identifiable on an
accompanying site plan. All wetlands and waters, and all streams (intermittent and perennial)
should be shown on a delineation map, whether or not impacts are proposed to these systems.
Wetland and stream evaluation and delineation forms should be included as appropriate.
Photographs may be included at the applicant's discretion. If this proposed impact is strictly for
Updated 11/1/2005
Page 7 of 12

6. List the cumulative im act to all Waters of the U.S. resultin from the ro'ect:
Stream Im act (acres): 0
Wetland Im act (acres): 0
O en Water Im act (acres): 0.8
Total Im act to Waters of the U. S. (acres) 0.8
Total Stream Im act (linear feet): 0
Isolated Waters
Do any isolated waters exist on the property? ^ Yes ~ No
Describe all impacts to isolated waters, and include the type of water (wetland or stream) and
the size of the proposed impact (acres or linear feet). Please note that this section only
applies to waters that have specifically been determined to be isolated by the USACE.
There are no isolated waters on the properly.
8. Pond Creation
If construction of a pond is proposed, associated wetland and stream impacts should be
included above in the wetland and stream impact sections. Also, the proposed pond should
be described here and illustrated on any maps included with this application.
Pond to be cre_ ated in (check all that apply): ®uplands ^ stream ^ wetlands
Describe the method of construction (e.g., dam/embankrnent, excavation, installalion of
draw-down valve or spillway, etc.): modification to existing pond
Proposed use or purpose of pond (e.g., livestock watering irrigation, aesthetic, trout pond,
lOCal StOTnlwatCr requlrelllerlt, etl;.). SiATIIIlw'clte~ 11Iai1dgeiYleClt
Current land use in the vicinity of the pond: existing pond
Size of watershed draining to pond: 47.64 ac Expected pond surface area: 48,648 sf
VII. Impact Justification (Avoidance and Minimization)
Specifically describe measures taken to avoid the proposed impacts. It may be useful to
provide information related to site constraints such as topography, building ordinances,
accessibility, and financial viability of the project. The applicant may attach drawings of
alternative, lower-impact site layouts, and explain why these design options were not
feasible. Also discuss how impacts were minimized once the desired site plan was
developed. If applicable, discuss construction techniques to be followed during construction
to reduce impacts. Rehabilitation of the stormwater pond was determined to be the most
feasible means of providing additional stormwater detention and improving water Quality for
the site's stormwater runoff. The proposed pond rehabilitation and outlet structure
i~rovements aze necessary to provide additional stonmwater management and capacity at
the existing stormwater pond. Proposed chances to the pond and surrounding areas have been
desigrled to improve the performance of the existing stormwater pond as a water quality
feature while minimizing disturbance to the landscape.
Updated 11/i/2005
Page 9 of 12

VIII. Mitigation
DWQ - In accordance with 15A NCAC 2H .0500, mitigation may be required by the NC
Division of Water Quality for projects involving greater than or equal to one acre of impacts to
freshwater wetlands or greater than or equal to 150 lineaz feet of total impacts to perennial
streams.
USACE - In accordance with the Final Notice of Issuance and Modification of Nationwide
Permits, published in the Federal Register on January 15, 2002, mitigation will be required when
necessary to ensure that adverse effects to the aquatic environment are minimal. Factors
including size and type of proposed impact and function and relative value of the impacted
aquatic resource will be considered in determining acceptability of appropriate and practicable
mitigation as proposed. Examples of mitigation that may be appropriate and practicable include,
but are not limited to: reducing the size of the project; establishing and maintaining wetland
and/or upland vegetated buffers to protect open waters such as streams; and replacing losses of
aquatic resource functions and values by creating, restoring, enhancing, or preserving similar
functions and values, preferable in the same watershed.
If mitigation is required for this project, a copy of the mitigation plan must be attached in order
for USACE or DWQ to consider the application complete for processing. Any application
lacking a required mitigation plan or NCEEP concurrence shall be placed on hold as incomplete.
An applicant may also choose to review the current guidelines for stream restoration in DWQ's
Draft Technical Guide for Stream Work in North Carolina (see DWQ website for most current
version.).
Provide a brief description of the proposed mitigation plan. The description should provide
as much information as possible, including, but not limited to: site location (attach directions
and/or map, if offsite), affected stream and river basin, type and amount (acreage/lineaz feet)
of mitigation proposed (restoration, enhancement, creation, or preservation), a plan view,
preservation mechanism (e.g., deed restrictions, conservation easement, etc.), and a
description of the current site conditions and proposed method of construction. Please attach
a separate sheet if more space is needed.
This project does not involve anv wetlands impacts or stream impacts and therefore does
not require a mitigation plan.
2. Mitigation may also be made by payment into the North Carolina Ecosystem Enhancement
Program (NCEEP). Please note it is the applicant's responsibility to contact the NCEEP at
[phone] to determine availability, and written approval from the NCEEP indicating
that they are will to accept payment for the mitigation must be attached to this form. For
additional information regarding the application process for the NCEEP, check the NCEEP
website at http://www.nceep.net/pages/irilieureplace.htm. If use of the NCEEP is proposed,
please check the appropriate box on page five and provide the following information:
Amount of stream mitigation requested (linear feet): n/a
Amount of buffer mitigation requested (square feet): n/a
Amount of Riparian wetland mitigation requested (acres): n/a
Updated 11/1/2005
Page 10 of 12

Amount of Non-riparian wetland mitigation requested (acres): n/a
Amount of Coastal wetland mitigation requested (acres): n/a
IX. Environmental Documentation (required by DWQ)
1. Does the project involve an expenditure of public (federaUstate/local) funds or the use of
public (federaVstate) land? Yes ~ No ^
2. If yes, does the project require preparation of an environmental document pursuant to the
requirements of the National or North Carolina Environmental Policy Act (NEPA/SEPA)?
Note: If you are pat sure whether a NEPA/SEPA document is required, call the SEPA
coordinator at [phone] to review current thresholds for environmental documentation.
Yes ^ No
3. If yes, has the document review been finalized by the State Clearinghouse? If so, please
attach a copy of the NEPA or SEPA final approval letter. Yes ^ No ^
X. Proposed Impacts on Riparian and Watershed Buffers (required by DWQ)
It is the applicant's (or agent's) responsibility to determine, delineate and map all impacts to
required state and local buffers associated with the project. The applicant must also provide
justification for these impacts in Section VII above. All proposed impacts must be listed herein,
and must be clearly identifiable on the accompanying site plan. All buffers must be shown on a
map, whether or not impacts are proposed to the buffers. Correspondence from the DWQ
Regional Office may be included as appropriate. Photographs may also be included at the
applicant's discretion.
Will the project impact protected riparian buffers identified within 15A NCAC ZB .0233
(Meuse), 15A NCAC 2B .0259 (Tar-Pamlico), 15A NCAC 02B .0243 (Catawba} 15A NCAC
2B .0250 (Randleman Rules and Water Supply Buffer Requirements), or other (please
identify )? Yes ^ No
2. If `des", identify the square feet and acreage of impact to each zone of the riparian buffers.
If buffer mitigation is required calculate the required amount of mitigation by applying the
buffer multipliers.
s ~P~t Required
Zone ram„„~~ f o*~ Multiplier
a r:..:._,...,._
3 (2 for Catawba)
1.5
Total
* Zone I extends out 30 feet perpendicular from the top of the near bank of channel; Zone 2 extends an
additional 20 feet from the edge of Zone 1.
If buffer mitigation is required, please discuss what type of mitigation is proposed (i.e.,
Donation of Properly, Riparian Buffer Restoration /Enhancement, or Payment into the
Riparian Buffer Restoration Fund). Please attach all appropriate information as identified
within 15A NCAC 2B .0242 or .0244, or .0260. NIA
Updated 11/1/2005
Page 11 of 12

XI. Stormwater (required by DWQ)
Describe impervious acreage (existing and proposed) versus total acreage on the site. Discuss stormwater
controls proposed in order to protect surface waters and wetlands downstream from the properly. If
percent impervious surface exceeds 20%, please provide calculations demonstrating total proposed
impervious level. The redeveloped site consists of SS 8S acres There aze 14 63 acres (26 2%) of existing
impervious area and 2.04 (3.7%) acres of additional vronosed impervious area. which results in a total of
16.67 acres (30%) of impervious surface for the site {Calculations of impervious surfaces are on Site
Area Tabulations sheet in the appendix) The Museum Expansion development wilt manage stormwater
throu¢h the use of several Brass swales. a vegetated swaie floodway reach and a constructed stormwater
marsh adiacent to the existing pond.
XII. Sewage Disposal (required by DWQ)
Clearly detail the ultimate treatment methods and disposition (non-discharge or discharge) of
wastewater generated from the proposed project, or available capacity of the subject facility. n/a
XIII. Violations (required by DWQj
Is this site in violation of DWQ Wetland Rules (15A NCAC 2H .0500) or any Buffer Rules?
Yes ^ No
Is this anafter-the-fact permit application? Yes ^ No
XIV. Cumulative Impacts (required by DWQ)
Will this project (based on past and reasonably anticipated future impacts) result in additional
development, which could impact nearby downstream water quality? Yes ^ No
If yes, please submit a qualitative or quantitative cumulative impact analysis in accordance with
the mast recent North Carolina Division of Water Quality policy posted on our website at
http://h2o.enr.state.nc.us/ncwetlands. If nq please provide a short narrative description:
Expansion of the North Carolina Museum of Art is a sinaulaz protect that will not lead to future
impacts on downstream water Quality The majority of the art museum's 165 acres will continue
to be managed as open space as this open space is a major focus of the museum's outdoor
environmental art program. Future site development may include trails temporary installations
and art installations, which will be of a dispersed nature and include only small amounts of
impervious area.
XV. Ottielr Circumstances (Optional):
It is the applicant's responsibility to submit the application sufficiently in advance of desired
construction dates to allow processing time for these permits. However, an applicant may
ose to list constraints associated with construction or sequencing that may impose limits on
work edules (e.g., draw-down schedules for lakes, dates associated with Endangered and
Threaten d Species, accessibility problems, or other issues outside of the applicant's control).
• ~ ' L'?
,pplieant/Agent's Signature Date
signature is valid only if an authorization letter from the applicant is provided.)
u~cea ivlraoos
Page 12 of 12

Permit No.
(to be provided by DVV(J)

~~ O~O~ W A TF9QG
~
NCDENR ~ ti
STORMWATER MANAGEMENT P ERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be 611ed out, printed and submitted.
The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
...
Project name North Carolina Museum of Art -Museum Expansion Project
Contact person Stephen H. Blake
Phone number [phone]
Date 3/2412008
Drainage area number
ItJ _~ItFtA
Site Characteristics
Drainage area 2,075,198 ft
Impervious area 706,108 ft
impervious 34.02605438 °~
Design rainfall depth 8.0 in
Storage Volume: Non-SR Waters
Minimum volume required 27,443 fta
Volume provided 243,517 ft3
Storage Volume: SR Waters
1-yr, 24-hr runoff depth 1.55 in
Pre-development 1-yr, 24-hr runoff 258790 ft3
Post-development 1-yr, 24-hr runoff 268286 ft3
Minimum volume required 9496 ft3
Volume provided 243,517 ft3
Peak Flow Calculations
Is pre/post control of the 1-yr 24-hr peak flow required? Y (Y or N)
1-yr, 24-hr rainfall depth 1.6 in
Rational C, pre-development (unitless)
Rational C, post-development (unitless)
Rainfall intensity: 1-yr, 24-hr storm 0.2 inmr
Pre-development 1-yr, 24-hr peak flow 60.2 ft3/sec
Post-development 1-yr, 24-hr peak flow 55.9 ft3/sec
PrelPost 1-yr, 24-hr peak flow control -4.3 ft3/sec
Basin Elevations
Basin bottom elevation 392.90 ft
Sediment cleanout elevation 393.90 ft
Permanent pool elevation 398.70 ft
Temporary pool elevation 399.75 ft
Volume and Surface Area Calculations
SAIDA ratio 0.02 (unitless)
Permanent pool, surface area required 46,874 ft
Permanent pool, surface area provided 46,874 ftz OK
Permanent pool volume 144,055 ft3
Average depth for SA/DA tables 3.073238896 ft OK
Forebay volume 10,993 ft3
Forebay % of permanent pool volume 8 % Must be approx. 20%, Adjust pond dimensions
Temporary pool, surface area provided 79,645 ftz
Fonn SW401-Wet Detention Basin-Rev.2 Parts I. 8 II. Design Summary, Page 1 of 2

Permit No.
(to be provided by DWC])

Drawdown Calculations
Treatment volume drawdown time 5 days OK
Treatment volume discharge rate 0.95 ft'Is
Pre-development 1-yr, 24-hr discharge 60.22 ft31s OK
Post-development 1-yr, 24-hr discharge 55.88 ft3/s OK
Additional Information
Diameter of orifice 3.00 in
Design TSS removal 85
Basin side slopes 3 :1 OK
Vegetated shelf slope 14 :1 OK
Vegetated shelf width 14 ft OK
Length of flowpath to width ratio 2.545454545 :1 Too short, increase ratio to at least 3:1
Length to width ratio 2.045454545 :1 OK
Trash rack for overflow & orifice? Y (Y or N) OK
Freeboard provided 1 ft OK
Vegetated filter provided? Y (Y or N) OK
Recorded drainage easement provided? Y (Y or N) OK ~
Capures all runoff at ultimate build-out? Y (Y or N) OK
Drain mechanism for maintenance or emergencies Ex. Drain
'~ SE1c' A~q-c fa'~
OK
Forth SW401-Wet Detention Basin-Rev.2 Parts I. & II. Design Summary, Page 2 of 2

Permit No.
~- (to be provided by DWQ)
IIC REQUIRED ITEMS"CHECKt.IST,
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will decay final review and approval of the project. Initial in the space provided fo
indicate the following design requirements have been met. ff the applicant has designated an agent, the agent may initial below. If a
requirement has.not been met, attach just cation.
Pagel Plan
Ini 'als Sheet No.
1. Plans (1° - 50' or larger) of the entire site showing:
-Design at ultimate build-out,
-Off-site drainage ('rf applicable),
- Delineated drainage basins (include Rational C coefficient per basin),
-Basin dimensions,
-Pretreatment system,
- High flow bypass system,
-Maintenance access,
- Recorded drainage easement and public right of way (RO111r), -'~.'
- Overflow device, and
- Boundaries of drainage easement.
2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing:
- Outlet structure with trash rack or similar,
- Maintenance access,
- Permanent pod dimensions,
- Forebay and main pond with hardened emer~ncy spillway,
- Basin cross-section,
-Vegetation speafication for planting shelf, and
- Filter strip.
3. Section view of the dry detention basin (1' = 20' or larger) showing:
- Side slopes, 3:1 or lower,
- Pretreatment and treatment areas, and
-Inlet and outlet stnictures.
4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
5. A table of devotions, areas, intxemental volumes & acalmulated vdumes for overall pond and for forebay,
to verify volume provided.
~_ 6. An assurance that the installed system will meet design specifications upon initial operation once the
project is cornplete and the enfire drainage area is stablized.
7. A c~tstrucfion sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
'~ 8. The supporting ca~ulations.
~~ 9. A copy of the signed and notarized inspection and maintenance (I&IN) agreement.
5~ 10. A copy of the deed restricfion. -~ S~ ~~,~~.J-^
Form SW401-Wet Detention Basin-Rev.1 Part III. Required Items Checklist, Page 1 of 1

Permit Number:
- (to be provided by DWQ)
O~O~ W ATF9QG
~ v
r
NCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
GRASSED SWALE SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part 111) must also be tilled out, punted and submitted along with all of the required information.
t. EIRIiiFA
Project name North Carolina Museum ofArt -Museum Expansion Project
Contact name Stephen H. Blake
Phone number [phone]
Date March 24, 2008
Drainage area number
11. 'ft~i
Site Characteristics
Drainage area 403,366 ft~
Impervious area 130,933 ftz
Percent impervious 32.5%
Design rainfall depth 5.3 inch
Peak Flow Calculations
10-yr, 24-hr runoff depth
10-yr, 24-hr intensity
Post-development 10-yr, 24-hr peak flow
Velocity
Maximum non-erosive velocity (peak 10-year storm)
Soil characteristics (enter "x" below)
Sand/silt (easily erodible)
Clay mix (erosion resistant)
Grass Type (enter "x" below)
Bermuda
Tall fescue
Bahiagrass
Kentucky bluegrass
Grass-legume mixture
Swale type: Fill out one of the options below:
Option 1: Curb Outlet Swale:
Maximum velocity
Side slopes
Swale length
Option 2: Convevance Swale. Seekino Pollutant Credit:
Maximum velocity for 10-yr storm
Side slopes
Swale length
Option 3: Convevance Swale. Not Seekin~Pollutant CreditCredit:
Maximum velocity
Side slopes
1.Zt3 in
0.22 in/hr
41.04 ft3/sec
5.5 ft/sec
Y
x (tJL~nJE Y1-1C SPEZ~FiC"Y~
N (Y or N)
:1
ft
N (Y or N)
ft/sec
:1
ft
Y (Y or N)
4.2 OK
6 :1 OK
Form SW401-Grassed Swale-Rev.1 Parts I and II. Project Design Summary, Page 1 of 2

Permit Number:
(to be provided by DWQ}
Swale Characteristics
Swale Shape: Enter an "x" in the appropriate cell below:
Trapezoidal x
Parabolic
V-shaped
Width of the bottom of the swale 10 ft
Width of the top of the swale 20-45 ft
Maintenance agreement: Is this included in the application? Y (Y or N)
This design is for the following design option:
Option 1: Curb outlet swale N
Option 2: Conveyance swale, seeking pollutant credit N
Option 3: Conveyance swale, not seeking pollutant credit N
Additional Information
Is the swale sized for all runoff from ultimate build-out? Yes OK
Is the BMP located in a recorded drainage easement with a

recorded access easement to a public Right of Way (ROW)? Yes (Y or N) OK
What is the distance from the bottom of the swale to the SHWT? 10.0 ft OK
What is the ground level elevation? 420.0 fmsl
What is the elevation of the bottom of the swale? 416.0 fmsl
What is the SHWT elevation? 406.0 fmsl
What is the longitudinal slope of the swale? 4.3 % OK
What is the depth of freeboard? 1.5 ft OK
Form SW401-Grassed Swale-Rev.1 Parts I and II. Project Design Summary, Page 2 of 2

Permit No:
(to be assigned by DWQ)
Ilt. REQUIRED ITEMS CHECKLIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package
will result in a request for additional information. This will delay final review and approval of the project. Initial in the space
provided to indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial
below. ff a requirement has not been met, attach justification.
Initials
Sly
Pagel Plan
Sheet No.
1. Plans (1" + 50' or larger) of the entire site showing:
- Design at ultimate build-out,
- Off-sfte drainage (if applicable),
- Delineated drainage basins (include Rational C coefficient per basin),
-Swale dimensions (width, length, depth),
- Maintenance access,
- Recorded drainage easement and public right of way (ROW), ~
-Grass species, and
- Boundaries of drainage easement.

~L
~~
SUS,
2. Plan details (1' = 50' or larger) for the grassed swale showing:
- Swale dimensions (width, length, depth),
- Maintenance access,
- Recorded drainage easement and public right of way (ROW), ~
- Design at ultimate build-out,
-Grass species,
- Off-site drainage (if applicable),and
- Boundaries of drainage easement.
Section view of the grassed swale (1" = 20' or larger) showing:
- Side slopes,
- Longitudinal slope,
- Freeboard
-Swale dimensions, and
- SHWT level(s)
4. Supporting calculations (including maximum velocity calculations for applicable storms)
5. An assurance that the installed system will meet design specifications upon initial operation once the
project is complete and the entire drainage area is stabilized.
6. A construction sequence that shows how the bioretention cell will be protected from sediment until the
entire drainage area is stabilized.
7. The supporting calculations (including underdrain calculations, if applicable).
S. A copy of the signed and notarized inspection and maintenance (I&M) agreement.
9. A copy of the deed restriction. .~ ~{~ ~~p~r}~-•rJ
SW401-Grassed Sw21e-Rev.1 0~.. ~~~ o...... + ..~

Wet lletention Basin lnspection and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
The wet detention basin system is defined as the wet detention basin,
pretreatment including forebays and the vegetated filter if one is provided.
This system (check one):
^ does ®does not incorporate a vegetated filter at the outlet.
This system (check one):
® does ^does not incorporate pretreatment other than a forebay.
Important maintenance procedures:
- Immediately after the wet detention basin is established, the plants on the
vegetated shelf and perimeter of the basin should be watered twice weekly if
needed, until the plants become established (commonly six weeks).
- No portion of the wet detention pond should be fertilized after the first initial
fertilization that is required to establish the plants on the vegetated shelf.
- Stable groundcover should be maintained in the drainage area to reduce the
sediment load to the wet detention basin.
- If the basin must be drained for an emergency or to perform maintenance, the
flushing of sediment through the emergency drain should be minimized to the
maximum extent practical.
- Once a year, a dam safety expert should inspect the embankment.
After the wet detention pond is established, it should be inspected once a month and
within 24 hours after every storm event greater than 1.0 inches (or 1.5 inches if in a
Coastal County). Records of inspection and maintenance should be kept in a known set
location and must be available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential roblem: How I will remediate the roblem:
The entire BMP Trash/debris is resent. Remove the trash/debris.
The perimeter of the wet Areas of bare soil and/or Regrade the soil if necessary to
detention basin erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer a lication.
Vegetation is too short or too Maintain vegetation at a height of
lon a roximatel six inches.

BMP element: ~ Potential
The inlet device: pipe or I The pipe is clogged.
swaIe
The pipe is cracked or
otherwise damaged.
Erosion is occurring in the
Swale.
How I will remediate the probl
Unclog the pipe. Dispose of the
sediment off-site.
Replace the pipe.
Regrade the swale if necessary to
smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
ft7hirP nrnhlamc Seri+}, nrncinn
The forebay Sediment has accumulated to Search for the source of the
a depth greater than the sediment and remedy the problem if
original design depth for possible. Remove the sediment and
sediment storage. dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Erosion has occurred. Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
revent future erosion roblems.
Weeds are present. Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the lants rather than s ra in .
The vegetated shelf Best professional practices Prune according to best professional
show that pruning is needed practices
to maintain optimal plant
health.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide aone-time
fertilizer application to establish the
ground cover if a soil test indicates
it is necessar .
Weeds are present. Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the lants rather than s ra in .
The main treatment area Sediment has accumulated to Search for the source of the
a depth greater than the sediment and remedy the problem if
original design sediment possible. Remove the sediment and
storage depth. dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Algal growth covers over Consult a professional to remove
50% of the area. and control the al al owth.
Cattails, phragmites or other Remove the plants by H~iping them
invasive plants cover 50% of with pesticide (do not spray).
the basin surface.

BMP element: Potential roblem: How I will remediate the roblem:
The embankment Shrubs have started to grow Remove shrubs immediately.
on the embankment.
Evidence of muskrat or Use traps to remove muskrats and
beaver activity is present. consult a professional to remove
beavers.
A tree has started to grow on Consult a dam safety specialist to
the embankment. remove the tree.
An annual inspection by an Make all needed repairs.
appropriate professional
shows that the embankment
needs re air.
The outlet device Clogging has occurred. Clean out the outlet device. Dispose
of the sediment off-site.
The outlet device is dama ed Re air or re lace the outlet device.
The receiving water Erosion or other signs of Contact the local NC Division of
damage have occurred at the Water Quality Regional Office, or
outlet. the 401 Oversight Unit at 919-733-
- 1786.
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 permanent pool depth reads 2.8 feet uz the main pond, the sediment
shall be removed.
When the permanent pool depth reads 426.5 feet in the forebay, the sediment
shall be removed.
BASIN ll1A(~lZAM
(fU in the blanks)
Sediment Removal
Bottom
Permanent Pool Elevation 398.7
395.9 ~ Pe manen'~
----------------- Volume
~ 395.0 -ft Min.
Sediment
Storage
Pool
~ Sediment Removal Elevation 395_9 ----- Volume
------~
Bottom Elevation
I-ft
FOREBAI'
MAIN POND
Storage

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:Mr. Dan Gottlieb
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.
~x. ~~
I, J G ~1K o , a Notary Public for the State of
n~o< ~~,,('e t :na ,County of (p f e~ K~ , do hereby certify that
~_(rp~-~; mot,, personally appeared before me this ~ ~
day of ~-pr, ~ , ~, and acknowledge the due execution of the
forgoinb wet detention basin maintenance requirements. Witness my hand and official
seal,
SEAL
My commission expires q /~ f 2010
Title: Deputy Director of Design, North Carolina Museum of Art

Grassed Swale Inspection and Maintenance Agreement
I will keep a maintenance record on this BMP. • This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
Important maintenance procedures:
The drainage area of the grassed Swale will be carefully managed to reduce the
sediment Load to the grassed swale.
After the first time fertilization to establish the grass in the Swale, fertilizer will
not be applied to the grassed swale.
The grassed swale will be inspected once a quarter. Records of inspection and
maintenance will be kept in a known set location and will be available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential roblem: How I will remediate the roblem:
The entire length of the Trash/debris is present. Remove the trash/debris.
swaie
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then re-sod
{or plant with other appropriate
species) and water until established.
Provide lime and aone-time
fertilizer a lication.
Sediment covers the grass at Remove sediment and dispose in an
the bottom of the Swale. area that will not impact streams or
]iMPs. Re-sod if necessar .
Vegetation is too short or too Maintain vegetation at a height of
Ion . a roximatel six inches.
The receiving water Erosion or other signs of Contact the ITC Division of Water
damage have occurred at the Quality 401 Oversight Unit at 919-
outlet. 733-1786.

v +~
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: Mr. Dan Gottlieb
Title: Deputy Director of Design, North CarolinA Museum of Art
Address: 2110 Blue Ride Road, Raleiuh. NC 27607 .
Signature:
Date: ~ ~ •~__n ~
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, .~t,~~.(`t,~ ~{, ~~ ~~it ~'. ~ , a Notary Public for the State of
/~bl~ (~,~,~ t i n..~ ,County of In1aY~.~ , do hereby certify that
~~~_('~-~~,~,~, personally appeared before me this Fstt'`
day of f3Pri 1 , ~`~, and acknowledge the due execution of the
forgoing wet detention basin maintenance requirements. Witness my hand and official
seal,
SEAL
My commission expires `~ ~25 ~Zo t~

~~O~~AT~RQG
> :~
O „ . ..~
Ste~~e Blake
:artifexED, Inc.
2363 Blake Street .202
Den~~er. CO 8020
p ~ ~ ` ~ (~ ~ V ~ 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
Apn116, 2008
NBRRO#08-08b
Wake County
BASLti
Neuse River X Tar-Pamlico
-(15A~TCAC-2B .0233)-- - - -- (15A NCAC 2&.0259) - _ --
Project dame: \C Museum of Art
Location Directions: Blue Ridge Rd, Raleigh NC
Subiect Stream: UT to House Creek
Date of Determination: March 21, 2008
Feature(s) Not
Subject Subject Start @ Stop@ Stream
Form Pts. Soil Survey USGS
Topo
Pond A X X X
A X X
Explanation: The feature(s) listed above has or have been located on the Soil Survey of Wake County, North
Carolina or the most recent copy of the USGS Topographic map at a 1:24,000 scale. Each feature that is checked
"Not Subject" has been determined not to be a stream or is not present on the property. Features that aze checked
"Subject" base been located on the property and possess characteristics that qualify it to be a stream There may be
other streams located on your property that do not show up on the maps referenced above but, still may be
considered jurisdictional according to the US Army Corps of Engineers andlor to the Division of Water Quality.
This on-site determination shall ezpire five (5) years from the date of this letter. Landowners or affected
parties that dispute a determination made by the DWQ or Delegated Local Authority that a surface water
ezists and that it is subject to the buffer rule may request a determination by the Director. A request for a
determination by the Director shaII be referred to the Director in writing c% Cyndi Karoly ,DWQ
Wetlauds/401 Unit, 2321 Crabtree Blvd., Raleigh, NC 27h04-2260. Individuals that dispute a determination
by the DWQ or Delegated Local Authority that Kezempts" a surface water from the buffer rule may ask for
an ad judicatory hearing. You must act within 60 days of the date that you receive this letter. Applicants are
hereby notified that the 60-day statutory appeal time does not start until the affected party (including
downstream and adjacent landowners) ffi notified of this decision. DWQ recommends that the applicant
conduct this notification in order to be certain that third party appeals are made in a timely manner. To ask
for a hearing, send a written petition, which conforms to Chapter ISOB of the North Carolina General
Statutes to the Ot~ice of Administrative Hearings, 6714 Mail Service Center, Raleigh, N.C. 27649-6714. This
determination is final and binding unless you ask for a hearing within 60 days.
IVotthC~~~
~Q
North Carolina Division of Wafer Quality Raleigh Regiomal O~'ice Surface Water Protection Phone [phone] Customer Service
Internet fi2o.enr.statenc.us 1628 Mail Service Center Raleigh, NC_27699-1628 FAX [phone]

•• NC Museum of Art
Wake County
April 16, 2008
Page 2 of 2
The (owner/future owners) should notify the Division of Water Quality (including any other Local, State, and
Federal Agencies) of this decision concerning any future correspondences regarding the subject property
(stated above). This project may require a Section 404/401 Permit for the proposed activity. Any inquiries
should be directed to the Division of Water Quality (Central Office) at (919)-733-1786, and the US Army
Corp of Engineers (Raleigh Regulatory Field Office) at (919)-876-8441.
Respecrfulhr, r:
_~- _ .~
~lar[in Rici~ond
Enzzronmental ~p.cialist
CC: Wetlands/ Stormwater Branch, 2321 Crabtree Blvd, Suite 2~0, Raleigh, NC 27604
Central Files
Nio ` Carolii
~11~atura!!r!
North Carolina Ilivision of Water Quality Raleigh Regional Office Surface Water Protection Phone [phone] Customer Service
Internet: h2o.enrstate.ne.us 1628 Mail Service Cen[er Raleigh, NC 27699-1628 FAX {919) 571-47tH 1-877-623-6748
. _ r_.._, n.._...~....,..r. ac..__.:..,, n,.,:,~.. c.....bw ro.__ cAO! Oenr.Jeri71lWL Onc1 /`m,c„mor Panty

., "1;opoGone - USUS Raleigh West (NC) Topo Map
~~
Page 1 of 1

• ~-..

i i
M*
0 0.1 0.2 0.3 0.4 0.5 km G
0 0.09 0.18 O.Za 0.36 0.45 mi
UTM 17 707700E 3965197N (NAD83/WGS84)
USGS Raleigh West (NC) Quadrangle ~=_8, 77;
Projection is UTM Zone 17 NAD83 Datum G=1.346

---- -- -- DWQ USE ONLY - ---
Date Received Fee Paid Permit Number
Olc--~~'~2V2
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMTI' APPLICATION F ~_ ; r~ "~'~ ~ ~~ r-`a
This form maybe photocopied for use as an original ~~~
~.PR 2 4 ZO~J8
I. GENERAL INFORMATION
DcNR-WATER OtiAUl`d
'~"ETLA.NDS AND STORMN:ATER 3RP,NGH
1. Applicants name (specify the name of the corporation, individual, etc. who owns the project):
North Carolina Museum of Art
2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance):
North Carolina Depaztment of Cultural Affairs/ Mr. Dan Gottlieb, Deputy Director of Design
3. Mailing Address for person listed in item 2 above:
2110 Blue Ridge Road
City:Raleigh State:NC Zip:27607
Phone: (919 ) 839-6262 Fax:
Email:
4. Project Name (subdivision, facility, or establishment name - should be consistent with project name on plans,
specifications, letters, operation and maintenance agreements, etc.):
North Carolina Museum of Art
Museum Expansion Project
5. Location of Project (street address):
2110 Blue Ridge Road
City:Raleigh County:Wake
6. Directions to project (from nearest major intersection):
From Interstate 440 head west on Raleigh-Chapel Hill Expy/ Wade Ave. Take the Blue Ridge Road exit.
Turn right at Blue Ridge Road.
7. Latitude:35 deg. 48 min. 36 sec. Longitude:-78 deg,. 42 min. 20 sec. of project
8. Contact person who can answer questions about the project:
Name:Stephen H. Blake Telephone Number: (720 )855-3721
Email: steve.blaket~3artifex.com
II. PERMIT INFORMATION:
1. Specify whether project is (check one):
®New
^Renewal OModification
Form SWU-101 Version 8.07 Page 1 of 4

2. If this application is being submitted as the result of a renewal or modification to an existing permit, list the
existing permit number and its issue date (if known)
3. Specify the type of project (check one):
^Low Density OHigh Density ^Redevelop ®Generai Permit ^Universal SMP QOther
4. Additional Project Requirements (check applicable blanks):
~CAMA Major ®Sedimentation/Erosion Control ®404/401 Permit ®NPDES stormwater
Information on required state permits can be obtained by contacting the Customer Service Center at
1-877-623-6748.
III. PROJECT INFORMATION
1. In the space provided below, summarize how stormwater will be treated. Also attach a detailed narrative
(one to two pages) describing stormwater management for the project .
stormwater will be treated through the use of several grass swales, a vegetated Swale floodway reach, and a
constructed stormwater marsh adjacent to the existingpond.
2. stormwater runoff from this project drains to the Neuse River basin.
3. Total Site Area: 47.64 acres 4. Total Wetlands Area: 0 acres
5. 100' Wide Strip of Wetland Area: acres (not applicable if no wetlands exist on site)
6. Total Project Area**:25.3 acres 7. Project Built Upon Area:33.0 %
8. How many drainage areas does the project have?5
9. Complete the following information for each drainage area. If there are more than two drainage areas in the
project, attach an additional sheet with the information for each area provided in the same format as below.
Basin Information Drainage Area 1 Drainage Area 2
Receiving Stream Name See Attached Sheet See Attached Sheet
Stream Class & Index No.
Drainage Area (sf)
Existin hn ervious* Area (sf)
Proposed Impervious*Area (sf)
% Impervious* Area (total)
Impervious* Surface Area Drainage Area 1 Drainage Area 2
On-site Buiidings (sf1 See Attached Sheet See Attached Sheet
On-site Streets (sf)
On-site Parking (sf)
On-site Sidewalks (sf)
Other on-site (sQ
Off-site (sf)
Total (sf):
* Impervious area is defined as the built upon area including, but not limited to, buildings, roads, parking areas,
sidewalks, gravel areas, etc.
Form SWU-101 Version 8.07 Page 2 of 4

VI. SUBMITTAL REQUIREMENTS
Only complete application packages will be accepted and reviewed by the Division of Water Quality (DWQ).
A complete package includes all of the items listed below. The complete application package should be
submitted to the appropriate DWQ Office. (Appropriate office may be found by locating project on the
interactive online map at http://h2o.enr.state.nc.us/su/msi mans.htm)
Form SWU-101 Version 8.07 Page 4 of 4
1. Please indicate that you have provided the following required information by initialing in the space provided
next to each item.
Initials
• Original and one copy of the Stormwater Management Permit Application Form SiQ~
• Original and one copy of the Deed Restrictions do Protective Covenants Form ~~
• Original of the applicable Supplement Form(s) and OkM agreement(s) for each BMP ~~
• Permit application processing fee of $505 ($4,000 for Express) payable to NCDENR ~1~1~j-
• Calculations do detailed narrative description of stonnwater treatment/management
• Copy of any applicable soil report ~
• Three copies of plans and specifications (sealed, signed & dated), including: .
- Development/Project name
- Engineer and firm
- Legend
- North arrow
- Scale
- Revision number & date
- Mean high water line
- Dimensioned property/project boundary
- Location map with named streets or NCSR numbers
- Original contours, proposed contours, spot elevations, finished floor elevations
- Details of roads, drainage features, collection systems, and stormwater control measures
- Wetlands delineated, or a note on plans that none exist
- Existing drainage (including off-site), drainage easements, pipe sizes, runoff calculations
- Drainage areas delineated
- Vegetated buffers (where required)
VII. AGENT AUTHORIZATION
If you wish to designate authority to another individual or firm so that they may provide information on your
behalf, please complete this section.
Designated agent (individual or firm):Stephen Blake
Mailing Address:2363 Blake Street Suite 202
City:Denver State:CO Zip:80205
Phone: (720 ) 855-3721 Fax: (720 ) 855-4210
Email: steve. blake®a r tifexed.com
VIII. APPLICANT'S CERTIFICATION
I, (print or type name of person listed in General Information, item 2) Dan Gottlieb
certify that the information included on this permit application form is, to the best of my knowledge, correct and
that the project will be constructed in conformance with the approved plans, that the required deed restrictions
and protective covenants will be recorded, and that the proposed project complies with the requirements of 15A
NCAC 2 .1
Signatu Date: ~ ~ ~ ' d

**Total project area shall be calculated based on the current policy regarding inclusion of wetlands in the built upon area
percentage calculation.
10. How was the off-site impervious area listed above derived
IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS
One of the following deed restrictions and protective covenants are required to be recorded for all subdivisions,
outparcels and future development prior to the sale of any lot. If lot sizes vary significantly, a table listing each
lot number, size and the allowable built-upon area for each lot must be provided as an attachment.
Form DRPC-1 High Density Commercial Subdivisions
Form DRPC-2 High Density Developments with Outparcels
Form DRPC-3 High Density Residential Subdivisions
Form DRPC-4 Low Density Commercial Subdivisions
Form DRPC-5 Low Density Residential Subdivisions
Form DRPC-6 Low Density Residential Subdivisions with Curb Outlets
By your signature below, you certify that the recorded deed restrictions and protective covenants for this
project shall include all the applicable items required in the above form, that the covenants will be binding
on all parties and persons claiming under them, that they will run with the land, that the required covenants
cannot be changed or deleted without concurrence from the State, and that they will be recorded prior to the
sale of any lot.
V. SUPPLEMENT FORMS
The applicable state stormwater management permit supplement form(s) listed below must be submitted for
each BMP specified for this project. Contact the Stormwater and General Permits Unit at [phone] for the
status and availability of these forms.
Form SW401-Low Density
Form SW401-Curb Outlet System
Form SW401-Off-Site System
Form SW401-Wet Detention Basin
Form SW401-Infiltration Basin
Form SW401-Infiltration Trench
Porm SW401-Bioretention Cell
Form SW401-Level Spreader
Form SW401-Wetland
Form SW401-Grassed Swale
Form SW401-Sand Filter
Low Density Supplement
Curb Outlet System Supplement
Off-Site System Supplement
Wet Detention Basin Supplement
Infiltration Basin Supplement
Underground Infiltration Trench Supplement
Bioretention Cell Supplement
Level Spreader/Filter Strip/Restored Riparian Buffer Supplement
Constructed Wetland Supplement
Grassed Swale Supplement
Sand Filter Supplement
Form SWU-101 Version 8.07 Page 3 of 4

Permit No.
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
(to be provided by DWQ
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form maybe photocopied for use as an original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes an application form, a wet detention basin
supplement for each basin, design calculations, and plans and specifications showing all basin and outlet
structure details.
I. PROJECT INFORMATION
Project Name: North Carolina Museum of Art -Museum Expansion Project
Contact Person: Stephen H. Blake Phone Number: (720 ) 855-3721
For projects with multiple basins, specify which basin this worksheet applies to:
elevations
Basin Bottom Elevation 392.90 ft.
Permanent Pool Elevation 398.70 ft.
Temporary Pool Elevation 399.74 ft.
areas
Permanent Pool Surface Area 48,87 sq. ft
Drainage Area
Impervious Area
47.64 ac
15.51 ac
volumes
Permanent Pool Volume
Temporary Pool Volume
Forebay Volume
Other parameters
SA/DA 1
Diameter of Orifice
Design Rainfall
Design TSS Removal 2
(floor of the basin)
(elevation of the orifice)
(elevation of the discharge structure overflow)
(water surface area at the orifice elevation)
(on-site and off-site drainage to the basin)
(on-site and off-site drainage to the basin)
144,055 cu. ft. (combined volume of main basin and forebay)
54,538 cu. ft. (volume detained above the permanent pool)
10,993 cu. ft. (approximately 20% of total volume)
1.21 X85%) 1.8 (90%) (surface area to drainage area ratio from DWQ table)
3 in. (2 to S day temporary pool draw-down required)
8 in.
85% % (minimum 85% required)
Form SWU-102 Rev 3.99 Page 1 of 4

Footnotes:
When using the Division SA/DA tables, the correct SA/DA ratio for permanent pool sizing should be computed based upon the
actual impervious % and permanent pool depth. Linear interpolation should be employed to determine the correct value for non-
standard table entries.
In the 20 coastal counties, the requirement for a vegetative filter may be waived if the wet detention basin is designed to provide
90%TSS removal. The NCDENR BMP manual provides design tables for both 85%TSS removal and 90% TSS removal.
II. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual
(N.C. Department of Environment, Health and Natural Resources, February 1999} and Administrative Code
Section: 15 A NCAC 2H .1008.
Initial in the space provided to indicate the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. If a requirement has not been met, attach justification.
Initials
l~ a. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet}.
b. The forebay volume is approximately equal to 20% of the basin volume. -~
C~ c. The temporary pool controls runoff from the design storm event.
~d. The temporary pool draws down in 2 to 5 days.
~e. If required, a 30-foot vegetative filter is provided at the outlet (include non-erosive flow
calculations)
~~: The basin length to width ratio is greater than 3: 1. ~
g. The basin side slopes above the permanent pool are no steeper than 3:1.
h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail).
i. Vegetative cover above the permanent pool elevation is specified.
~j'~ A trash rack or similar device is provided for both the overflow and orifice.
~l~ A recorded drainage easement is provided for each basin including access to nearest right-
of-way. ~~
1. If the basin is used for sediment and erosion control. during construction, clean out of the
basin is specified prior to use as a wet detention basin.
~. m. A rnechanisrn is specified which will drain the basin for maintenance or an emergency.

III. WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and the
vegetated filter if one is provided.
This system (check one} 0 does ~oes not incorporate a vegetated filter at the outlet.
This system (check one) 'does 0 does not incorporate pretreatment other than a forebay.
Form SWU-102 Rev 3.99 Page 2 of 4

Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet 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 wet 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 mariner that will not adversely impact water quality (i.e.
stockpiling near a wet 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 permanent pool depth reads 2.8 feet in the main pond, the sediment shall be removed.
When the permanent pool depth reads 2.8 feet in the forebay, the sediment shall be removed.
BASIN DIAGRAM
Ull in the blanks)
Permanent Pool Elevation 398.7
Sediment Rer~'1ova1 El. 395.9
- - - - - - - - - - Sediment Removal Elevation 395.9 75 /
------- °
Bottom Ele ation 395 25%~ --------------------------------------------- -------
FOREBAY
Bottom Elevation 395 25
MAIN POND
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6. 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.
Form SWU-102 Rev 3.99 Page 3 of 4

7. All components of the wet detention basin system shall be maintained in good working order.
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: 7RK-~~ C~~LiE3
Title: ~~re-i-~yf aF- ~~~,v-v~~ tnq $~ ~esigy~
Phone:
Signature:
Date: ~~ ~ • ~_~
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, .~Gtrtq~ K. Gam/ ~ ~ ,~', C~,~>, a Notary Public for the State of d r ~~ ~,y, ,
County of A~ , do hereby certify that n ~.~ ~_(' t'
personally appeared before me this $~ day of n ~ 2o'aff ,and acknowledge the due
execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal,
SEAL
My commission expires q ~25 I20 ~~
Form SWU-102 Rev 3.99 Page 4 of 4

RTIFEX ~ inc
ENVIRONMENTAL DESIGN
2363 Blake Street, Suite 202
Denver, CO 80205
[phone] phone
[phone] fax
www.°rtlJexed.com
April 23, 2008
Permit Attachment
Wet Detention Basin and Grassed Swale Supplements -Additional Explanations
1. The existing pond has been rehabilitated to maximize the storage for suspended sediment by
providing three distinct forebays at the entrance of all stormwater outfalls tot eh pond. Given the
existing pond's large initial wet pool, however, a maximum ratio of forebay volume to wet pool volume
of 8% is provided. It was determined preferable to retain the wet pool size, even though it is sign~cantly
larger than required for the site's water quality requirements. The required ratio of total sediment
storage to site impervious area has been provided in the proposed design.
2. The existing pond configuration is relatively rectangular. With grading of the pond margins and
aquatic shelf, and the effects of vegetation around the pond perimeter, a length to width ratio of 2.5:1
has been provided in the proposed design. Relocation of the outfall may help improver this ratio for the
majority of the site's stormwater runoff, but was not deemed feasible within this project due to cost
considerations.
3. The property is owned in its entirety by the State of North Carolina. The portion of the property in
question is part of the North Carolina Museum of Art Park, and will not be sold or subdivided. The area
where the BMPs are to be created is currently dedicated to Stormwater Management, with existing
storm sewers, inlets and a detention pond. Access is provided from the public right of way along Blue
Ridge Road, along the site roads and concrete path, which also serves as the pond embankment and
access, and provides access to the existing electrical power transmission towers.