20091318 Ver 2_Modifications_20100712

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July 6,2010
Ms Tasha McCormick
USACE
Asheville Regulatory Field Office
151 Paton Ave,Rm 208 @
Asheville,NC 28801-5006 i5 L5 tJ
RE:Action ID:2010.0023 JUL 1 2 C t0
DWQ Project#:09-1318
Emergency Vet Clinic: Town of Boone,Watauga County,NC DENR-WATER QUALITY
- Modfication for Culvert Design Change WETLMos MD STOR.tirWATER BRANCH
Dear Tasha:
Inducted with this letter is a modified detail showing a concrete apron e)den&V approximately 6 feet
out from each end of the proposed dual-72"by W culvert structure.This change was requested by the
manufacturer of the precast structure, and is needed to provide greater stru ducal stability at inlet and
outlet ends of the precast concrete headwall and wingwaN structure. As shown in the pemitted design,
all flows less than bankfull will be maintained in the low Dow pipe, a concrete wall has been added to.
the upstream concrete apron with top elevation at approximately bankfull.
As a result of this change the amount of permanent impact to Hodges Creek will increase from 15 to 25
linear feet. Temporary impact lengths will remain the same and the total impact to all streams on the
project will increase from 48 linear feet to 58 linear feet. 1 have also attached sheet 5 of 11 from the
PCN form showing this change.
On behalf.of my client, Dr. David limey, I am requesting approval of this modification. If you have any
questions regarding this information please call me at 828-297-6946,thank you.
Sincerely,
J n C.Was
President,ENV Er vironmental Consulting Services Inc.
: Ms sue ca�iood
ike Trew
Mr.David Unzey

C. Proposed impacts Inventory
J. Impacts Summary
1 a. Which sections were completed below for your project(check all that apply):
®Wetlands ®Streams-tributaries ❑Buffers
❑Open Waters ❑Pond Construction
2. Welland Impacts
If there are wetland impacts proposed on the site,then complete this question for each wetland area impacted.
2a. 2b. 2c. 2d. 2e. 2f.
Welland impact Type of jurisdiction
number— Type of impact Type of wetland Forested (Corps-404, 10 Area of impact
Permanent(P)or (if known) MM—non-404,other) (acres)
Temporary
W1 ®P❑T Fill Riparian Yes ®Corps 0.065
®No ®DWQ
W2 ®P❑T Fill Riparian ❑Yes ®Corps 0.02
®No ®DWQ
W3 []POT excavation Riparian ❑Yes ®Corps No®No ®DWQ
W4 [IP❑T excavation Riparian- ❑Yes ®Corps 0.002
. No ®DWQ
W5 ❑ P❑T [I Yes ❑C�
❑No ❑DWQ
W6 ❑ P❑T ❑Yes ❑Corps
❑No ❑DWQ
2g.Total wetland impacts .098
2h.Comments:Wetlands are adjacent to trout waters
3. Stream Impacts
If there are perennial or intermittent stream impacts('mduding temporary impacts)proposed on the site,then complete this
question for all stream sites impacted.
3a: 3b. 3c. 3d. 3e. 3f. 39.
Stream impact Type of impact Stream name Perennial Type of jurisdiction Average Impact
number- (PER)or (Corps-404,10 stream length
Permanent(P)or intermittent DWQ—non..404, width (linear
Temporary('f) (INT)? other) (feet) feet)
S1 RP❑T Pipe Extension Hodges Creek ® PER ®Corps 9 25
❑INT ®DWQ
® PER ®Corps
S2 ❑P®T Utilities Hodges Creek ❑INT ®DWQ 9 8
Construction, PER ®Corps
S3 [] POT Grade Control and Hodges Creek 9 25
bank protection INT ® DWQ
S4 ❑ P❑T ❑PER ❑Corps
❑INT ❑DWQ
S5 ❑P❑T [I PER ❑Corps
❑INT ❑DWQ
S6 ❑ P❑T ❑PER ❑Corps
❑INT ❑DWQ
31L Total stream and tributary. impacts 58
3i.Comments:
Page 6 of 12
PCN Form—Version 1.3 December 10,2008 Version

I
ROP SED DRIVE EMERGENCY VET CLINIC
CULVERT INSTALLATION DETAIL
N 12-2-2009 MOD 6-29-2010
-
� NOTES
RIPRAP AT OUTLET OF Grade and install filter fabric and large riprap
�— HIGH-FLOW PIPE at outlet of proposed high-flow pipe
Precast concrete headwalls, Wingwalls, and apron to
CULV INLET be used to minimize time of construction and
CONTROL RM CMP use of wet concrete in proximity to stream.
Culvert installation to be performed in phases
7 Existing pipe to be shifted north and used as
CONCRETE L F 65 temporary diversion pipe while proposed low-flow
WALL :3 1 7 0- pipe and headwalls are installed in the dry. LoW-flaw
CMP - pipe invert to be one-foot below streambed.
W pj Following installation of proposed low-flow pipe,
HODGES CRaa
flow will be shifted to new pipe and proposed high-
flow pipe and headwall will be installed. High flout
pipe to be installed 0.8 feet above low-flow pipe.
3 1 88 Install inflow control berm according to detail and stabilize
�` �\ all disturbed stream bank and riparian areas.
Banks to be covered With coir matting or approved
8o ECAST ONCRET equal and seeded With temporary seed mix according
AP ON to Erosion Control Plan,
Install rock vanes as needed to protect stream
banks immediately above and below culvert.
Coordinate with Environmental Consultant on
design and placement of structures.
Overseed all disturbed areas with seed mix ERNMX-178
SCALE 1 "= 15 or approved equal.
0 15 30 PROJECT ENGINEER
MUNICIPAL ENGINEERING SERVICES COMPANY, PA
PO BOX 349, 178 - NC 28607
PH: WS-M-1787
SKPKYYLLINE S YORS
CULVERT INLET CONTROL BERM DETAIL PO BOX 442, BOWe NC 29807
(NTS) 828-252-3353
E AL
NT
NSU
E I IRONMENTAL CS TTIMp SERVICED, INC.
3 54 INGER RD, B�"R.ELK NC 28504
2.6'-3' NATIVE STONE BOULDERS PLACED TO NORMAL FLO� CULVERT: INSTALL ITH INVERT e2e-2G7-�CREATE A NEAR-BANKFULL BERM IN FRONT ONE-FOOT B LO STREAM BED ELErW7
OF THE HIGH-FLON PIPE. TIE TO BANKFULL W YATION. PERM�IT DRAWINGS PREPAID BY ENy-ECD, INC.
WALL. UBD BAR JrA AID RAN PROVIDED BY PROJECT
CONCRETE BANKFULL WALL TO EXTEND i
FROM HEADWALL TO EDGE OF APRON. TO
MAINTAIN ALL FLOWS LESS THAN BANKFULL
72' CMP IN LOW FLOW PIPE.
72'
PROPOSED BANKFULL (APPROX)
BANK
APPROX. EX. STREAM BED
C NCRETE APRO