NC0004308_OFF-SITE_20160831

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ALCOA
VIA ELECTRONIC MAIL
Alcoa Badin Works
293 Highway 740
Badin, NC 28009
�Or
August 22, 2016
Ms. Teresa Rodriguez OVA OF WM R=
North Carolina Department of Environmental Quality
Division of Water Resources
Water Quality Permitting Section, Complex Permitting Branch
1617 Mail Service Center
Raleigh, NC 27699-1617
Physical Address: 512 N. Salisbury Street, 9th Floor -Archdale Bldg, Raleigh, NC 27604
Re: Alcoa Badin Works - Badin, North Carolina
NPDES Permit No. NC 0004308
Dear Ms. Rodriguez:
In recent months it was discovered that storm water from off-site of the Badin Works property is contributing to
areas of standing water on portions of the Badin property. Alcoa completed a site reconnaissance of the area, which
confirmed the grade break in the topography, as well as overall shallow grade of the drainage ditches, which were
originally designed to carry this surface water north to Outfall 013. However, due to the shallow grade and silting of
the ditches, storm water is able to pool, and the water must either evaporate or infiltrate into the subsurface.
Alcoa believes it would be more efficient to re -grade and direct surface water to the more steeply sloped southern
direction and then tie into the facility's existing storm sewer system. This would result in the non -contact storm
water identified above to flow to Outfall 005. During our June 30, 2016 teleconference regarding this matter, you
suggested your office would be comfortable with Alcoa's suggested modifications. As requested during this call,
please find the accompanying updated drainage basin map. Finally, based on our discussion, Alcoa understands no
further permit modifications are necessary to redirect this clean, non -contact storm water.
Alcoa plans to complete this action in the 3rd quarter of 2016. Please feel free to contact me or Randall Kiser with
any questions you might have.
Sincerely,
ParkJ. Gss
APGI Yadk' Division Technical Manager
Badin Works Facility Manager
Enclosure