SW8020516_HISTORICAL FILE_20061005 (2)

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW8
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
HISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
lw g \ 00 5
YYYYMMDD

P. 1
* * COMMUNICATION RESULT REPORT ( OCT. 6.2006 10:10AM ) *
TTI
FILE MODE OPTION
616 MEMORY TX
ADDRESS (GROUP)
9-7635631
* *
NCDENR WIRO
1------ PAGE
REASON FOR ERROR
E-1) HANG UP OR LINE FAIL E-2) BUSY
E-3) NO ANSWER E-4) NO FACSIMILE CONNECTION
State of North Carolina
Department of Environment and Natural Resources
Wilmington Regional Office
[phone]
Michael F. Easley, Governor William G, Ross Jr,, Secretary
FAX COVER SHEET
Date: 6G # pages (excluding cover)
O E From: Gloria Jones
CO
C: Division; Express .Permitting
FAX #:3 — 3 FAX#: [phone]
RE -MARKS:
'/ 9t;rl
127 Cardinal Driva Extension, \vllmington. Y.C. 28405-3845 T91cphnne(910) 796-7215 Fax[phone]
An Equal Opportunity AtOnnnlive Action Employer
P. 9/9

TRwp ENGINEERING, P.C. E C V'L LD
0 419 Chestnut Street
Wilmington, North Carolina 28401 SEP b[UU5
Ph6ne: [phone] • FAX: [phone]Rt,,__
September 1, 2006
NCDENR
Division Water Quality
127 Cardinal Drive
Wilmington, NC 28405-3845
Attn: Ms. Linda Lewis
Re: Lot 57-Northehase
SW8 020516 Mod.
TE 05163
Dear Linda:
In response to your comments dated August 22, 2006, we offer the following:
1. A note has been added.
2. The corrected application page 2 is enclosed.
3. The corrected calculations are enclosed.
4. A highlighted C-1 is enclosed.
5. The detail has been corrected.
6. The detail has been corrected.
7. The normal pool has been dimensioned.
8. The detail has been corrected.
Please review for approval and contact us with any questions, comments or if you need
additional information. Thank you.
Sincerely,
Tripp Engineering, P.C.
Jonathan W. Ham, E.I.
JWH:bgw
Enc.

9/1/2006 Lot 57 - Northchase 05163
JWH Stormwater Calculations
Total Drains %Area
s .ft.
acres
37,026
1 0.85
Im ervious Area
Land Use
sq. ft.
acres
Building Area
13,568
0.31
Asphalt Area
7,176
0.16
Concrete Area
1,708
0.04
Total
1 22,452
0.52
Stormwater Calculations:
Time of Concentration
Hydraulic Length (L) = 285 ft.
change in Height (H) = 4 ft.
Tc = (L' /H)'d°O / 128
= 3.14 min.
Flow for 2 year, 6 hour Storm (0,)
CPRE= (CPRE) x (40) x (Area)
= 0.90 cfs
Cposr = (Cposr) x (I+o) x (Area)
= 2AE cfs
84
P = 3.30 in. fo2yr, 6 hr storm
S = 1000/CN - 10
1.90
Depth (D)= (P-(0.2)(S)]2 / [P+(0.8)(S)]
1.77 in.
Time to Peak Flow:
TP= [(43.5)(D)(Area)J/D2,posr
26.59 min.
Detention Pond Design:
Pond Size:
Elevation
R.)
Surface Area
(sq. ft.
Normal Pool
41.00
3.878
Flood Pool
42.30
5.246
Top of Bank
44.25
7.769
Bottom of Pool
38.00
397
Provided Storage Volume:
Vol. _ ((Normal pool SA+ Flood Pool SA) / 2]
x (F.P. elev. - N.P. elev.)
5,931 cu. ft.
RECEIVED
SEP 0 5 2006
PROJ #
&w-So 20S((o MyD
%impervious= 0.606
= 60.6%
say 61.0%
CPRE= 0.25
Cposr= (%tmp.)(.95)+(1 %imp.)(.25)
0.68
12= 4.25 in/hr
ha= 492 in/hr
Flow for 10 year, 6 hour Storm (DER)
CPRE _ (CPRE) x (125) x (Area)
1.05 cfs
Qrosr = (CPosr) x (125) x (Area)
2.84 cfs
Soil Stora a Capacity for 10 year Storm:
CN = (98)(% imp.) + (60)(1-% imp.)
= 84 .
P = 4.82 in. for 10 yr, 6 hr storm
S = 1000/CN - 10
1.90
Depth (D)= [P-(0.2)(S)]2 / [P+(0.8)(S)]
- 3.11 in.
Time to Peak Flow:
Tp= [(43.5)(D)(Area)]/D10.P0,r
40.39 min.
State Surface Area Requirement at normalpool:
Pond side slopes = 3 :1
Depth below N.P. = 3 ft.
SAJDA = 0.0711
(Chart for 90 % TSS Removal for Wet Detention
Pond without Vegetative Filter
Required SA = (SA/DA) x (Total Drainage Area)
2,633 s . ft.
State Volume Required for Storage of first 1" of runoff
Rv= .05+,009(%imp)
= 0.595746
V= (Design rainfall)(Rv)(Drainage Area)
- 1,838 cu. ft.
Ess/ '
acer C
<--I-1.o6
05163pondl

�, . �; as a
:-y� ssssa
��. �°, s agar �.;�,
a�
"'aoo ,'�' C��� e�°�
°-�.aa..��e��+

9112006 Lot 57 - Northchase
JWH Stormwater Calculations
Pond Volume:
ttom SA = 391 sq. ft.
NormBoal Pool SA = 3,878 sq. ft.
Vol. _ ((N.P. SA + Bottom SA) / 2] x (N.P. of. - Bottom el.)
6,412 cu. ft.
Forebav,
Required Volume
Vol. = 20% of storage volume
1,282 cu. ft.
Outlet Structure Design:
Flow for 2-day drawdown:
for 1st 1' of stormwater,
Q = Required Vol. / 172,800 sec. (2-days)
= 0.011 cfs
Required Area of Pipe for 2-day drawdown:
A= Q/(CdxSQRT(2xgxh)]
Cd = 0.6
g = 32.2 fUs'
h = (F.P. elev.- N.P. elev.) /2
0.65 ft.
A= 0,0027 sq. ft.
Diameter of Pioe for 2-dav drawdown:
DIA. = SQRT[(A x 4) / pi)
- 0,0591 ft.
- 0.71 in.
'Use: 0.5 in diameter pipe
Outlet Structure Check:
Using a 4' x 4' Basin,
Perimeter L = - 16 ft.
Q= CIA
C = (% imp)(95) + (1-% imp.)(.25)
0.68
1= 4.92 in. for a 25 yr. Storm
A= 0.85 Acres
2.84 cfs
Q= CwxLxH
H = (Q / (Cw x L)]m
Cw = 3
0.15 ft.
Peak elevation = Flood pool elevation + H
42.45 ft.
Provided Volume
Bottom SA =
102 sq. ft.
Normal Pool SA =
785 sq. ft.
Vol. _
I(N.P. SA+ Bottom SA) / 2] x (N.P. el. - Bottom el.)
=
1,331 cu. ft.
Flow for 5-day drawdown:
for 1 st 1' of stormwater,
Q = Required Vol. /432,000 sec.(5-days)
0.004 cfs
Re uired Area of Pipe for 5-day drawdown:
A= Q/[Cdx SQRT(2xgxh)]
Cd = 0.6
g = 32.2 ftJs2
h = (F.P. elev. - N.P. elev.) / 2
0.65 ft.
A= 0.0011 sq. ft.
Diameter of Pipe for 5-day drawdown:
DIA. = SQRT[(A x 4) / pi]
= 0.0374 ft.
0.45 in.
05163
05163pondl 2 of

SW8 020516 Mod. Express Review Comments
Subject: SW8 020516 Mod. Express Review Comments
From: Linda Lewis <[e-mail]>
Datep.Tue, 22 Aug 2006 12:48:37 -0400
To: Joriatfian Ham <jonathan w [e-mail]>, Tripp Engineering <[e-mail]>
Jonathan;.
In addition to my previous comments, attached please find my remaining Express
review comments, assuming that Mr. Jensen will be the permittee of record for Lots
54, 55, 56 and 57.
Linda
020516mod.aug06.doc Content -Type: application/msword
f Content -Encoding: base64
1 of 1 8/23/2006 9:28 AM

SWO 020516 Mod.
Subject: SWO 020516 Mod.
From: Linda Lewis <[e-mail]>
Date: Tue, 22 Aug 2006 12:21:14 -0400
To: Tripp Engineering <[e-mail]>, Jonathan Ham <[e-mail]>
Jonathan:
I'm in the process of reviewing this application, but I'm confused and want to make
sure you, Mr. Jensen and I all understand what it is you are asking of the Division
in regards to this permit modification. You submitted Lot 57 as a modification to
SW8 020516, which was originally issued to Chris Wilcox. It covered the
construction on Lots 54, 55 and 56 within Technology Court, permitted under SW8
961004. By submitting as a permit modification to SW8 020516, you realize that Mr.
Jensen will become the permittee of record for Lots 54, 55 and 56 as well as Lot
57?
If this is not your intent, please submit the project as a stand alone high density
wet detention project.
Linda
I of 1 8/22/2006 12:49 PM

SW8 020516 Mod. Express Review Comments
1
Subject: SW8 020516 Mod. Express Review Comments
From: Linda Lewis <[e-mail]>
Date: Tue, 22 Aug 2006 12:48:37 -0400
To: Jonathan Ham <jonathan_w [e-mail]>, Tripp Engineering <[e-mail]>
Jonathan,
In addition to my previous comments, attached please find my remaining Express
review comments, assuming that Mr. Jensen will be the permittee of record for Lots
54, 55, 56 and 57.
Linda
020516mod.aug06.doc Content -Type: application/msword
Content -Encoding: base64
I of 1 8/22/2006 12:48 PM

RE: SW8 020516 Mod. Express Review Comments
Subject: RE: SW8 020516 Mod. Express Review Comments
From: 'Jonathan Ham" <[e-mail]>
Date: Tue, 22 Aug 2006 12:55:43 -0400
To: [e-mail]
Hi Linda,
Mr. Jensen is to be the permittee of record for all four lots. Chris Wilcox was and is the
contractor for the construction of the previous project and the current one as well. Thank you
so much for your quick response and I will address the comments as soon as possible. Have a
great day!
Sincerely,
Jonathan
Jonathan W. Ham, E.I.
Civil Engineering
Tripp Engineering, P.C.
419 Chestnut Street
Wilmington, NC 28401
(910)-763-5100
From: Linda Lewis <linda.lewis@ncmail. net>
To: Jonathan Ham <jonathan w ham@hotmail. com>, Tripp Engineering <trippeng@ec. rr.com>
Subject: SWS 020516 Mod. Express Review Comments
Date: Tue, 22 Aug 2006 12:48:37 -0400
Jonathan,
In addition to my previous comments, attached please find my remaining Express review comments,
assuming that Mr. Jensen will be the permittee of record for Lots 54, 55, 56 and 57.
Linda
« 020516mod.aug06.doc »
Get real-time traffic reports with windows Live Local Search
http://local live com/default.aspx?v=2&cp=42.336065--109.392273&style=r&lvl=4&scene=3712634&trfc=l
I of 1 8/22/2006 1:00 PM

TRIPP ENGINEERING, P.C.
419 Chestnut Street
Wilmington, North Carolina 28401
Phone: [phone] • FAX: [phone]
August 21, 2006
NCDENR
Division Water Quality
127 Cardinal Drive
Wilmington, NC 28405-3845
Attn: Ms. Linda Lewis
Re: Lot 57 - NorthChase
New Hanover County, NC
TE 05163
Dear Linda:
IkEC]EIV D
AUG 2 2 2006
In response to your correspondence dated August 17, 2006, we offer the following:
1. A corrected wet detention supplement page 3 is enclosed.
2. An updated, signed and notarized offsite supplement is enclosed.
Please review for approval and contact us with any questions, comments or if you
need additional information. Thank you.
Sincerely,
Tripp Engineering, P.C.
WP7-/''//��
Jonathan W. Ham, E.I.
JWH:bgw
Enc.

t-YPMSS-- U- bf 2Z <)("'
TRIPP ENGINEERING, P.C. 5GvXo2O51& /(Op
(la- wet- PC4J
419 Chestnut Street��
Wilmington, North Carolina 28401
Phone: [phone] • FAX: [phone]
August 22, 2006
NCDENR
Division Water Quality
127 Cardinal Drive
Wilmington, NC 28405-3845
Attn: Mr. Cameron Weaver
Re: Lot 57 Northchase — EXPRESS REVIEW
New Hanover County, NC
TE 05163
Dear Cameron:
AUG 177 ruLa
/nk cGe Sinn
0 1/.
C7,` �
Enclosed please find two (2) sets of plans, one (1) signed original and one (1)
copy of the application form with narrative, one (1) wet detention basin supplement, two
(2) sets of calculations and one check for the express review fee.
Please review for approval and contact us with any questions or comments.
Thank you.
Sincerely,
Tripp Engineering, P.C.
Jennifer Rohde
JLR:dcb
Enc.

Lo7 NorthChase
Subject: Lot 57 NorthChase
From: Linda Lewis <[e-mail]>
Date: Thu, 17 Aug 2006 09:52:09 -0400
To: Jennifer Rohde <[e-mail]>
CC: Cameron Weaver <[e-mail]>
Jennifer:
I received this Express application today, and have a few preliminary comments:
1. A wet detention pond may never be less than three (3) feet deep, therefore, the
sediment removal depth listed on the wet pond supplement, which is currently
specified as 2.251, must be revised to 3.01. Essentially, no sediment will be
allowed to accumulate in this pond.
2. The narrative indicates that some of this runoff will be treated by an offisite
pond, however, no offsite supplement was provided with the application.
Please submit these items prior to the scheduled Express review date of Augusut 22,
2006.
Thanks,
Linda
1 of 1 8/17/2006 9:54 AM

JUN 30,2006 02:32P Tripp Engineering 9107635631
page 2
NCDENR MDJ
North Caroline Departrnent of Environment and Natural Resources
127 Cardinal Drive Extension. Wilmington, NC 28405 [phone] FAX [phone] n
Request for Express Permit Review
FILL-IN all informadon below and CHECK required Pe►mitis).
FAX or email to Cameron.WeaverOncmall.net along with a narrative and vicinity man of the project lociti , oo� / �-7
Projects must be submitted by 9:00 A.M. of the review date, unless prior arrangements are made. \�
APPLICANT Name Carsten Jensen
Company
Address.4536-1 Technology Drive City/State Wilmington NC Zip 28405 County New Hanover
Phone [phone] Fax Email
PROJECT Name Lot 57 Northchase
PROJECT SYSTEM(S) TRIBUTARY TO Smith Creek (STREAM NAME) Cane Fear RIVER BASIN
ENGINEER/CONSULTANT Phillip Tripp
State or National Environmental Policy Act (SEPA, NEPA) — EA or EIS Required
❑ STREAM ORIGIN Determination; # of stream calls; Stream Name
® STORMWATER ❑ Low Density ® High Density -Detention Pond ❑ High Density -Other
Wetlands MUST be addressed below ❑ Low Density -Curb & Gutter ❑ High Density -Infiltration ❑ Off Site
❑ COASTAL ❑ Excavation & Fill ❑ Bridges & Culverts ❑ Structures Information
MANAGEMENT ❑ Upland Development ❑ Marina Development ❑ Urban Waterfront
❑ LAND QUALITY ❑ Erosion and Sedimentation Control Plan with acres to be disturbed.
WETLANDS (401) Wetlands on Property ❑ Yes ® No Isolate Wetlands on Property ❑ Yes ❑ No
Check all that aonly Wetlands Will Be Impacted ❑ Yes ® No Welland Irp acts: Acre(s)
Wetlands Delineation has been completed ❑ Yes [I No LJ Buffers Impacted: Acre(s)
USACOE Apporval of Delineation completed ❑ Yes ❑ No
404 Application in process w/USACOE ❑Yes ❑No I Permit received from USACOE❑Yes ❑No
401 Application required ❑ Yes ❑ No If Yes, ❑ Regular ❑ Express
Addldonal fees, not to exceed 50% of the original Express Review permit application fee, may be charged for
subsequent reviews due to the Insufficiency of the permit applications.
For DENR use only
SUBMITTAL DATES: Fee Split for multiple permits:
SW $
CAMA $
LQS $
401 $ Total Fee Amount $

JUN 30,2006 02:32P Tripp Engineering 9107635631
0
Job No. 05163
TRIPP ENGINEERING, P.C.
419 Chestnut Strect, Wilmington, NC 28401
Phone: [phone] • FAX: [phone]
Email: trippcng(,ec.rr.com
LETTER OF TRANSMITTAL
To: _NCDENR
Attention: Sameron Weaver
Subject: EXPRESS PERMIT REVIEW - Lot 57 Northchase
X FAX TRANSMITTAL: NUMBER OF PAGES INCLUDES COVER 4_
I am sending you: ( X ) ATTACHED ( ) UNDER SEPARATE COVER
( ) Prints ( ) Tracings ( ) Copy of letter ( ) Specifications ( X ) Other
Cooies Item No Description
1 ExgrecS Permit Review Reguest
-- 1 S ormwater Narrative
These are transmitted as checked below:
( ) For Approval ( X ) For Your Use ( ) Sign & Return ( ) Review
Remarks: Please let us know the time and date for the ore aooll atf n m etino
cc:
Signed: Jonathan Ham
page 1

06/07/06
Stormwater Narrative
Lot 57 Northchase
New Hanover County, NC
TE05163
Lot 57 Northchase is an existing 2.46 acre tract of land. The site is proposed for an
industrial office building in addition to the existing office building. The proposed
construction includes one 13,658 sf building, 7,502 sf of asphalt, and 1,708 sf of concrete
sidewalk totaling 22,778 sf of proposed impervious. Existing construction includes one
17,990 sf building, 31,482 sf of asphalt, 2,380 sf of concrete, bringing the total for the
site to 74,630 s£ This total impervious constitutes 68.70% impervious coverage.
Stormwater runoff for the existing construction is handled by an offsite wet detention
pond designed to exceed the state's requirement of the first one inch of runoff. The
proposed construction will be handed by an onsite wet detention pond designed for the
state's requirement of the first one inch of runoff and the county's 10-year pre -post
requirement. Both ponds will drain to Smith Creek with a classification of C-SW.