20081121 Ver 2_More Info Letter_20111220

Beverly Eaves Perdue
Governor
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North Carolina Department of Environment and Natural Resources
Division of Water Qualiiy
Coleen H Sullins
Director
December 20 2011
Diamond W Builders LLC
Mr Gary White
9814 US Highway 311 Suite 2
Archdale North Cazolma 27263
Sub�ect Property Diamonds Keep Subdivision
Dee Freeman
Secretary
DWQ Pro�ect # 08 1121
Randolph County
REQUEST FOR MORE INFORMATION STORMWATER MANAGEMENT PLAN
Dear Mr Wlute
On March 15, 2010, the NC Division of Water Quality (DWQ) issued a 401 Water Quality
Certification to impact 1381mear feet of Caraway Creek and 0 493 acres of npanan wetlands to
construct Diamonds Keep Subdivision in Archdale North Carohna Concurrent with the issuance of
the 401 Water Quality Certificahon the DWQ approved a stormwater management plan for tlus
pro�ect Condition number three (3) of the certification requ�res that the stormwater management
plan as approved by DWQ be constructed and operahonal before any permanent building is occupied
at the site and be maintamed m perpetuity
On November 18, 2011, the DWQ received a modified stormwater management plan (dated
November 17 2011) that was submitted by your consultant, Mr Mack Summey, Jr of Summey
Engmeering Associates
The DWQ has determmed that the stormwater management plan was mcomplete as discussed below
Addihonal Informahon Requested
1 Please provide an updated overall srte plan showing the dra�nage azea boundanes and impervious
surface calculations one mch topograpluc contours and proposed locat�ons of BMPs Your
narrative refers to Sheet 1 of 17 wluch was omitted from the subnuttal
2 Please provide a table that illustrates your proposal for the trade off of dra�nage and BUAs that
shows how ttus plan treats an equivalent or greater BUA than a convent�onal plan requinng 85
percent TSS removal from the lugh density drainage areas
3 Please explaui whether the proposed Sand Filters will be constructed m accordance with the
previously approved stormwater management plan for this pro�ect or whether those designs will
be modified
4 For the wet detention basins please provide the requ�red items checklists and all requued items
that were omitted on the submittal received by the DWQ on November 18 2011 Some of the
Wetlands Buffers Stormwater Compliance and Permittmg Unit (WeBSCaPe)
1650 Mad Serwce Center Raleigh North Carolina 276991650
Phone [phone] FAX [phone]
Internet http //portal ncdenr org/web/wqlws
An Equal Opportun�iy \ Affirmative Action Employer

Diamonds Keep SD
Page 2 of 2
December 20 2011
omitted items mclude a depicrion of the proposed boundaries of the dramage easements, a stage
storage table for each pond and a soils study that documents the level of the seasonal lugh water
table
5 Please provide liners for the wet detent�on ponds if requ�red per 5ection 10 3 8 of the BMP
Manual
6 Please provide specifications for the anri seep collars
7 Please correct enors m the values of the dnving head that have been entered in the Wet Detentaon
Basm Supplement Forms The drivmg head is equal to the temporary pool elevat�on muius the
permanent pool elevation
8 It does not appeaz that the correct SA/DA ratios for the wet detention ponds have been selected
Please refer to Table 10 3 of the BMP Manual
9 Please provide calculations of the average depth of the wet detention ponds wluch must be a
mirumum of three feet per the BMP Manual Please note that the average depth is not eqwvalent
to the maxunum depth
10 For ease of maintenance, the DWQ lughly recommends the use of a submerged onfice outlet as
depicted on page 10 18 of the BMP Manual
The DWQ will require the above additional mformat�on to finalize review of the stormwater
management plan for the sub�ect property Please provide tlus informahon within 30 calendar days
If you have any quesrions, please telephone me at [phone]
Smcerely
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Annette M Lucas P E
Wetlands, Buffers and Stormwater Compliance and
Permittmg Umt
AML/aml
cc Sue Homewood DWQ WSRO
John Thomas USACE Raleigh Regulatory Field Office
Mack Summey Summey Engmeenng Associates P O Box 968 Asheboro NC 27204
File Copy
F�lename 081121D�mondaKeepSD(Randolph) SVV Hold