20060367 Ver 1_Information Letter_20070731

Re: Construction issue on U-3344A (Airport Blvd.) in Wake Co.
Subject: Re: Construction issue on U-3344A (Airport Blvd.) in Wake Co.
From: Rob Ridings <[e-mail]>
Date: Tue, 31 Ju12007 15:05:22 -0400
To: Chris Murray <[e-mail]>
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Chris,
I agree, this shouldn't need a mod as long as the riprap is completely within already permitted impact area. Just include it in
as-builds.
-Rob
Chris Murray wrote:
Reference: NCDOT permit application dated 3/3/06
DWQ 401 WQCBuffer Authorization dated 4/24/06 (Project No. 20060367)
USACE Action ID No.: Not Issued
Rob and Eric,
The Department is currently constructing the widening of Airport Boulevard in Wake County and have encountered as
stability problem on the project at Site 1 (near 21+50 Rt). This issue is addressed below:
Issue
The NCDOT is currently constructing a rip_rap lined lateral base ditch located on the right hand side of the project to
Station 21+00 Rt.. Runoff from development on the other side of the roadway enters three 24" concrete pipes (which go
under the roadway) that discharge to the lateral base ditch around Station 21+10 Rt. In this particular discharge area, the
plans call for not using rip rap for stability as the ditch is actually being "excavated" in a wetland. Close examination of
the attached permit drawing do indicate that it is permitted as "excavation" in wetland. The off-site water that is being
conveyed through the 24" concrete pipes is just blowing out the lateral base ditch. The Department proposes to install
Class I rip rap in the footprint of the lateral base ditch that has been permitted as "excavation" in wetland which will
provide long-term stability. This will extend to approximately 21+g5 Rt.
Permit Analysis
The slight construction revision addressed in this email does not result in additional impacts to wetlands, streams or
riparian buffers. Downstream water quality will not be negatively impacted by this proposal. In fact, the rip rap may slow
down the water velocity prior to where it enters the unimpacted wetland near 22+00 Rt. A review of the permit
application indicates that the Department has paid compensatory mitigation for the wetland impacts at this site. We would
only be proposing to add rip rap in the area depicted as "excavation" in wetland. It appears that this slight construction
revision should not require a permit modification.
Please let me know if you agree with my assessment of the issue. Thank you in advance for your review of this
information.
Chris Murray
1 of 3 7/31 /2007 3:06 PM

Re: Construction issue on U-3344A (Airport Blvd.) in Wake Co.
~--rrr
2 of 3 7/31/2007 3:06 PM