20120348 Ver 1_Staff Comments_20120912

Lucas, Annette
From: Lucas, Annette
Sent: Wednesday, September 12, 2012 11:12 AM
To: Witherspoon, Lauren
Cc: Lowther, Brian; Lucas, Annette
Subject: 12 -0348 Marquee Station
Attachments: 12 -0348 Marquee Station.docx
LC,
Comments are attached (courtesy of Brian Lowther in the SW unit).
Thanks,
AL
Annette M. Lucas, PE
Environmental Engineer
NCDENR I DWQ I Wetlands and Stormwater Branch
1650 Mail,Service Center, Raleigh, NC 27699 -1650 (Mail)
512 N. Salisbury St, Raleigh, NC 27604 1 9th Floor (Location & Parcels)
Phone: [phone] Fax: [phone] Email: Annette. Lucas(cDncdenr.gov
Website: http://Portal.ncdenr.org/web/wq/"swpZws/401
A Before printing this email, please consider your budget and the environment.
E -mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to
third parties.
1)

12 -0348 Marquee Station
BL comments
September 12, 2012
The plans (CE -2) state that the amount of impervious is 2.2 acres; however, the Supplement
Form states that it is 1.6 acres. The calculations for the WQV are based on a 1.6 acre drainage
area. Also, it appears that there is an offsite drainage that may not be included in the WQV
calculation. Please address these inconsistencies.
2. The Supplement Form indicates that an Internal Water Storage (IWS) is used in the bioretention
area but the plans do not reflect this.
3. The plans are missing the BMP detail sheet.
4. The outlet of the bioretention area is directly adjacent to the wetland. Please provide
calculations showing that the discharge would at a non - erosive velocity.

Lucas, Annette
From:
Lowther, Brian
Sent:
Tuesday, September 11, 2012 4:24 PM
To:
Lucas, Annette
Subject:
Review comments for Marquee Station
Annette,
I have reviewed the documents for Marquee Station and I have a few comments below that may need to be addressed
by the engineer.
- The plans (CE -2) say the amount of impervious is 2.2 acres and the supplement says 1.6 acres. The calculations
for the WQV are done with 1.6 acres. Also, it looks like there is offsite drainage I am not sure is included in the
WQV calculation. Please ask the engineer to fix these inconsistencies.
- The supplement indicates IWS is used but I don't think that is the case.
- Second set of plans is missing the BMP detail sheet and has a different one instead.
- The outlet of the bioretention basin is directly to the wetland. I didn't see any calculations showing the
discharge would be non - erosive.
Let me know if you have any questions about these.
Brian
Brian C Lowther, PE
Environmental Engineer
NCDENR I DWQ I Stormwater Permitting Unit
1617 Mail Service Center, Raleigh, NC 27699-1617
512 N. Salisbury St, Raleigh, NC 27604
(919) 807 -6368
brian. lowtherQa ncdenr. gov
http: / /portal.ncdenr.org/web /wg /ws /su
E -mail correspondence to and from this _address may -be subject to the North Carolina Public Records Law and maybe disclosed to
third parties unless the content is exempt by statute or other regulation.