20000659 Ver 1_More Info Received_20010116

3111 Environmental Technology PO Box 33331
and SerNices St. Paul, MN 55133-3331
651 778 6442
January 11, 2001
V'%5 1, 1 1A
Federal Express
Todd St. John
North Carolina Dept. of Environment and Natural Resources
Division of Water Quality, 401 Certification Unit
4401 Reedy Creek Road
Raleigh, NC 27607
Re: Individual 401/404 Permit Application
USACE Action ID 200021531
DWQ # 001007
3M Site in Pittsboro, North Carolina
Dear Mr. St. John:
c.
Per your request of 1/4/01, please refer to the following comments and documents for your review:
1) Site plan maps at scale of 60:1 or larger
Please find enclosed numerous construction drawings at the map scale requested. These drawings show the
pond contours, pond inlets and outlets, culverts associated with the stormwater ponds in the 3M
manufacturing area of the Pittsboro site. The following is the list of attached drawings:
a) PBOR-888-C-704 (Overall 3M plant)
b) PBOR-888-C-209E (Grading & Drainage Plan - Pond 3)
c) PBOR-888-C-210D (Grading & Drainage Plan - Pond 1)
d) PBOR-888-C-210E (Grading & Drainage Plan - Pond 2)
e) PBOR-888-C-409E (Sewer Plan - Pond 3 inlet/outlet structures)
f) PBOR-888-C-410D (Sewer Plan -Pond 1 inlet/outlet structures)
g) PBOR-888-C-410E (Sewer Plan- Pond 2 inlet/outlet structures)
2) Shortcuircuting of inlet and outlet strictures on pond 2
Please note that the culvert running from pond 1 into pond 2 has been relocated to prevent short-circuiting
in pond 2. Drawing PBOR-888-C-410E shows this inlet relocated at an angle discharge into the center of
pond 2, instead of across from pond 2 outlet. Shortly after your last site visit, this culvert/inlet was dug-up
and moved to the new location as shown on the attached drawing.
In summary, the attached supporting documentation should allow you to finish your review of the
Stormwater BMP requirements. If you have any questions, please contact me at the above address or call
me at [phone].
Sincerely,
&/
Belinda Wirth
Senior Environmental Engineer
Enc.
cc: (via first class mail)
John Thomas, Army Corps of Engineers, 6508 Falls of the Neuse Road, Suite 120, Raleigh, NC, 27615