20160196 Ver 2_More Info Received_20170217

PILOT ENVIRONMENTAL INC
U.S. Army Corps of Engineers
Attn: Mr. David Bailey
Raleigh Regulatory Field Office
Wilmington District U.S. Army Corps of Engineers
3331 Heritage Trade Drive, Suite 105 "fA
Wake Forest, North Carolina 27587
North Carolina Division of Water Resources
Attn: Ms. Sue Homewood
Winston-Salem Regional Office - 401 Wetlands Unit
450 West Hanes Mill Road
Winston Salem, North Carolina 27105
February 16, 2017
Reference: Request for NCDEQ-DWR #16-0196 401 Water Quality Certification Modification
Response to USACE SAW -2016-0049 Compliance Inspection
Proposed Qorvo Facility
Thorndike Road
Greensboro, Guilford County, North Carolina
PEI Project 1653.2
Dear Mr. Bailey and Ms. Homewood:
Mr. Robin Team of Carolina Investment Properties, Inc. received an electronic mail (e-mail)
dated February 3, 2017 from the U.S. Army Corps of Engineers (USACE) requesting information
following a compliance inspection at the referenced site. Impacts to Waters of the US (WoUS)
as a result of the project were previously authorized by the USACE in a Nationwide Permit
(NWP) dated April 8, 2016 (SAW -2016-0049) and a North Carolina Department of
Environmental Quality (NCDEQ) Division of Water Resources (DWR) 401 Water Quality
Certification (WQC) dated April 11, 2016. The purpose of this letter is to provide responses to
noted items during a February 2, 2017 USACE compliance inspection and to request a 401 WQC
modification from the NCDEQ-DWR.
USACE Comment 1): The 48" culvert shown on the permitted plans under the road crossing
does not appear to be buried 1' below the bed of the stream as shown on the permitted plans
(Plan Sheet C2.2). Please explain this discrepancy.
Applicant Response: The applicant recognizes that during construction the contractor could not
bury the 48" culvert one foot below the existing stream bed (see attached As -Built Profile).
During installation of the culvert, the contractor encountered areas of rock that limited the
PO Box 128, Kernersville, NC 27285
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Request for NCDEQ-DWR #16-0196 401 Water Quality Certification Modification
Response to USACE SAW -2016-0049 Compliance Inspection
Proposed Qorvo Facility
February 16, 2017
installation of the culvert such that it was not practical for burial of the culvert one foot
beneath the streambed.
According to USACE NWP 39 Regional Condition 3.6 -Safe Passage Requirements for Culverts,
"culverts greater than 48 inches in diameter will be buried at least one foot below the bed of
the stream. Culverts 48 inches in diameter or less shall be buried or placed on the stream bed
as practicable and appropriate to maintain aquatic passage, and every effort shall be made to
maintain the existing channel slope."
The installed culvert is 48 inches in diameter. The intermittent stream has been dry and not
contained water on numerous site visits by PEI throughout different weather conditions and
times of the year. The intermittent stream crossing is located approximately 100 feet down
gradient of a pond; thus, resulting in limited seasonal flow of the intermittent stream.
Additionally, the location of the pond respective to the culvert location, affords a very limited
area of stream that could potentially afford aquatic habitat. The reach of intermittent stream
between the pond and culvert location affords minimal aquatic habitat due to weakly defined
meanders, limited riffle -pool complexes and absent depositional bars/benches. Additionally,
PEI has not observed the presence or evidence/indicators of aquatic species within the reach of
stream between the pond and the location of the 48 -inch culvert. Based on our observations,
the stream provides minimal aquatic habitat. Therefore, the applicant feels that the above
conditions of the USACE NWP 39 have been satisfied in regards to the placement of the culvert
at the elevation of the streambed, as documented within the As -Built Profile, and that no
further action or written waiver from the above NWP 39 Regional Condition from the USACE
should be required.
According to the NCDEQ-DWR Water Quality Certification Number 3890, 13) Placement of
Culverts and Other Structures in Waters and Wetlands, "Placement of culverts and other
structures in waters and streams must be below the elevation of the streambed by one foot for
all culverts with a diameter greater than 48 inches, and 20 percent of the culvert diameter for
culverts with a diameter less than or equal to 48 inches, to allow low flow passage of water and
aquatic life."
As documented above, the stream is a very weak intermittent stream that affords minimal
aquatic habitat. Additionally, based on the contractor encountering areas of rock during site
culvert installation, burying the culvert 20 percent of culvert diameter was not practical.
Therefore, the applicant requests written waiver from the NCDEQ-DWR and modification of the
existing 401 WQC.
USACE Comment 2): The rip rap dissipater pad at the downstream end of the 48" culvert was not
keyed into the stream bank, and is not placed such that it is no higher than the previously existing
stream bed elevation as shown on the permitted plans (Plan Sheet C2.2). Specifically, the downstream
—13 I.f. of the rip rap pad includes rip rap piled between 1 and 2' higher than the stream bed elevation

Request for NCDEQ-DWR #16-0196 401 Water Quality Certification Modification
Response to USACE SAW -2016-0049 Compliance Inspection
Proposed Qorvo Facility
February 16, 2017
(see attached picture). Please reset the rip -rap pad such that it is placed no higher than the previously
existing stream bed elevation as shown on the permitted plans (Plan Sheet C2.2).
Applicant Response: The applicant recognizes that the rip -rap dissipater was incorrectly
installed. The applicant's contractor returned to the site and made repairs to properly key rip -
rap into the stream bank and correctly ensured it was not placed higher than the previously
existing stream bed elevation. Photographs, collected following the repair, that document the
repaired conditions are included as attachments.
Based on the above information, it is the applicant's opinion that the installed culvert, repair to
the rip -rap dissipater and provided documentation that no further action is required by the
applicant or the USACE following issuance of this letter. Additionally, the applicant requests
modification of the existing 401 WQC that provides written waiver of the NCDEQ-DWR WQC for
the installed culvert to not be buried 20 percent of culvert diameter below the existing
streambed. If there are questions regarding this response/request, or a need for further
information, please contact us at [phone].
Respectfully submitted,
PILOT ENVIRONMENTAL, INC.
Bradley S. Luckey, PWS
Project Manager
Attachments: As -Build Profile
Michael T. Brame, PWS
Principal
Site Photographs
NCDEQ-DWR 401 Review Fee Check of $570.00

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CONC .HEADWALL
STA, 0+45.60 ELEV, 848.61
(PIPE INV IN)
(13RIGINAL STREAM BED IN)
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SCALD V = 80'
STAB 1+50 ELEVi 846.05
(PIPE INV OUT)
STAo 1+74.34 ELEV, 845.95
—(TOP OF KEYED IN RIP—RAP)
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0+00 0+50 1+00 1+50 2+00
SCALD V = 80'
STAB 1+50 ELEVi 846.05
(PIPE INV OUT)
STAo 1+74.34 ELEV, 845.95
—(TOP OF KEYED IN RIP—RAP)

SITE PHOTOGRAPHS
Photograph 1- View of rip -rap dissipater.
Photograph 2 - View of rip -rap dissipater.