20000659 Ver 2_More Info Received - Email_20161212

Higgins, Karen
From: Chris Wu <[e-mail]>
Sent: Monday, December 12, 2016 2:54 PM
To: Higgins, Karen; Burdette, Jennifer a
Cc: Trevor Crawford; James Zieglmeier
Subject: RE: 3M
Attachments: PBOR-888-C-723 esc-plan-with pumps.pdf
Karen — here is 3M's response to your questions from November 22, 2016.
Under Phase 1 expansion, an additional stripping area will be added, which is referred to as "Stripping Area V (see
attached figure). This area is located in between 2 of the streams, outside the buffers, and outside the contributing
drainage area to these streams. An additional temporary sediment basin will be added as a BMP to control runoff during
stripping activities. This stripping area will allow 3M to extend the existing quarry northward between these streams and
create a low -point in the topography which can be utilized, in conjunction with permanent/temporary stormwater
diversions, to intercept surface water which would normally flow through these streams to Jordan Lake.
Phase 2 expansion will require these streams to be immediately diverted to the existing quarry, away from Jordan Lake.
In order to do that, temporary water pumping measures will be implemented until earthen diversion channels can be
constructed. There are 3 intermittent streams that will be diverted to "Stripping Area V. The individual streams and
respective measure(s) to divert surface water runoff to the existing quarry are listed below:
Stream SA3:
Upon Phase 2 start, a 4' tall embankment with 2:1 side slopes will be constructed within the streambed and pumping
measures will be implemented immediately. This embankment will create a temporary surface water reservoir capable
of storing 0.33 ac -ft. A temporary diesel powered pump capable of producing minimum 5,000 gpm of flow will ensure
that the water level in the temporary reservoir is regulated. A 25yr-24hr storm event pumped at 5,000 gpm will maintain
a minimum freeboard to top of embankment of 1.66'. This stream is intermittent and the pump will be operated based
on water levels within the temporary reservoir.
While pumping occurs, a stormater diversion will be constructed to intercept this stream flow and divert the water
"stripping Area V. The diversion will be approximately 600 feet long and it is anticipated to take about 3-4 weeks to
construct (pumping would need to occur for this construction duration). The diversion is designed to pass the 100yr-
24hr storm with 12" minimum of freeboard.
Additional Data:
Contributing Drainage Area: 6.9 ac
25yr-24hr peak flow rate: 15.83 cfs
25yr-24hr runoff volume: 1.66 ac -ft
Temporary Pump Flow Rate: 5,000 gpm (11.14 cfs)
Anticipated pumping duration: 3-4 weeks
Stream SA4:
Pumping will occur immediately out of the existing ACOE jurisdictional pond which is near the end of this stream where
planned to be removed. A temporary diesel powered pump capable of producing minimum 5,000 gpm of flow is
estimated to provide a minimum 12" of freeboard to top of existing embankment for the 25yr-24hr storm event.
While pumping occurs, a stormwater diversion will be constructed to intercept this stream flow and divert the water to
the quarry. This specific stormwater diversion will be a portion of the diversion needed for stream SA3 (SA3 and SA4 will

share one diversion). Stream SA4 is closer to "Stripping Area E", and it is anticipated to take 1-2 weeks to construct this
portion of the diversion. Pumping would need to occur for 1-2 weeks on an intermittent basis. The pump will operate
based upon water levels within the existing pond.
Additional Data:
Contributing Drainage Area: 8.02 ac
25yr-24hr peak flow rate: 25.65 cfs
25yr-24hr runoff volume: 1.93 ac -ft
Temporary Pump Flow Rate: 5,000 gpm(11.14 cfs)
Anticipated pumping duration: 1-2 weeks
Stream SBI:
Pumping will not be required at this location because "stripping area V will be nearby, and construction within the
buffer/streambed areas will be planned during a time when there is not any flow. This is an intermittent stream that
does not always flow. An 150 foot long stormwater diversion will be constructed immediately which will be capable of
passing the 100yr-24hr storm with 12" minimum of freeboard. This diversion should take approximately 1 week to
construct.
Please let us know if you have any questions.
Thanks,
Chris
Christopher Wu
Water Resource Project Manager
Environmental Consulting & Technology, Inc.*
7208 Falls of Neuse Road, Suite 102 ( Raleigh, NC 27615
919.861.8888 (Office) 1919.423.1045 (Cell)
cwu(abectinc.com I www.ectinc.com
*Operating within North Carolina as "Environmental Consulting & Technology of North Carolina, PLLC."
From: Higgins, Karen[mailto:[e-mail]]
Sent: Tuesday, November 22, 2016 4:29 PM
To: Christopher Wu <[e-mail]>
Cc: Burdette, Jennifer a <[e-mail]>; Trevor Crawford <[e-mail]>; James Zieglmeier
<[e-mail]>
Subject: RE: 3M
Chris -
Thanks for taking the time to meet with Jennifer, Kim and me this morning. I wanted to follow up on our
meeting to request some additional information regarding the drainage away from the Jordan Lake
watershed:
• Please provide additional details regarding the pumps and their installation. What kind of pumps will
be used, where will they be installed, how will the intake in the channel be constructed, and how will
they be powered. Will a temporary road be constructed to install the pumps? Please include design
drawings if available.
• What is the long term plan for maintaining the water flow towards the Deep River and not the Jordan
Lake watershed, considering it may be several decades before that area is mined? Will it continue to
be pumped for all that time or will something else be constructed long-term.

Please feel free to email us the requested info instead of sending paper copies.
Thanks-
Karen
hanks-
Karen
Karen Higgins
401 & Buffer Permitting Branch Supervisor
Division of Water Resources
Department of Environmental Quality
919 807-6360 office
klrur.:_Ih_i.c iu�s(rncdenir.gov
512 N. Salisbury Street, Suite 942-E, Raleigh, NC 27604
1617 Mail Service Center, Raleigh, NC 27699-1617
EFn7 it correspomYence to amY from this aYY Yr ss is subiect to the
lVoill`r Carolina Public ReconYs Law amY rr7a�Yisclose� Y to thi Y paili s,
From: Christopher Wu [rna_ilto. C u(�ectlnc._ carry]
Sent: Thursday, November 17, 2016 1:52 PM
To: Higgins, Karen <ka_re_n_:_h.igg�_n C__n denr:gcav>
Cc: Burdette, Jennifer a <Je_n_n fey...Burdette_C�_n_cd_en_r:.ggy>; Trevor Crawford <tccra_w ordC _rrrrr m :com>; James Zieglmeier
__ ...........
<iazie�lmeier(c�mmm.com>
Subject: Re: 3M
Karen - I am available then and invited Jim Zieglmeier and Trevor Crawford with 3M as well.
Thanks
Christopher Wu
Water Resource Project Manager
Environmental Consulting &Technology, Inc.
7208 Falls of Neuse Road, Suite 102
Raleigh, NC 27615
919-861-8888 (office) 1919-423-1045 (cell)
Sent from my iPhone
On Nov 17, 2016, at 1:35 PM, Higgins, Karen <kers_n_:_h.lg.g�nsC__ndenr:gcrv> wrote:
Hi Chris -
I just got off the phone with Craig Bromby regarding the 3M expansion project. He asked that
we speak with you regarding the drainage of land to Jordan Lake/Deep River and the Jordan

Lake buffer rules. Would it be possible to have a meeting or conference call with you next
Tuesday, Nov. 22 at 9:00 to discuss further?
Thanks-
Karen
hanks-
Karen
Karen Higgins
401 & Buffer Permitting Branch Supervisor
Division of Water Resources
Department of Environmental Quality
919 807-6360 office
kiru.:_Ih_i.c iu�s(ru�cdeu�ir.gov
512 N. Salisbury Street, Suite 942-E, Raleigh, NC 27604
1617 Mail Service Center, Raleigh, NC 27699-1617
lV ill? Carolina Public ReconYs Law amY n7 .V V �Yiscl se�Y to thinY pads s,