20061925 Ver 1_More Info Received_20070228

•N
:'W E•~ BURDETTE LAND CONSULTING, INC.
308D W Millbrook Road, Suite 200 -Raleigh, North Carolina 27609
Telephone [phone] -Fax [phone]
S
February 28, 2007
Mr. Ian McMillan
401 Oversight/Bxpress Review Permitting Unit
North Carolina Division of Water Quality
2321 Crabtree Boulevard, Suite250
Raleigh, North Carolina 27604
RE: Additional Information
Mill Ridge Subdivision -Phase 5 & 6
DWQ Project # 06-1925
BLC Project #: 60044
Dear Mr. McMillan:
`~ ~~ _ _
.'.~ ~ _r:i~:
Attached is a revised site plan showing all proposed stormwater and sediment and erosion
controls, level spreader worksheets, a plan detail of the proposed level spreaders, and an
Operations and Maintenance agreement for all of the proposed level spreaders to provide
the additional information requested for the subject project.
We have placed a building envelope on lot number 28, revised the drawing to show pipe
P-7's discharge through level spreader P-11, and added a level spreader at pipe P-5 as
requested. Mr. Alan Keith of Diehl & Phillips indicated that P-7 had been routed to P-11
at the time the worksheet for this level spreader was prepared, but an older version of the
drawing was inadvertently submitted. Therefore, the level spreader worksheets provided
in the original PCN application for pipes P-ll, P-21, and P-25 remain valid.
The site plan was also revised to reflect a buffered stream channel present across the
northwestern property corner. We originally believed this channel was located off of the
property. The stream channel and associated wetlands were subsequently located, and
the site plan revised to avoid any impacts to these features by removing a proposed cul-
de-sac and lot number 6. The presence of this buffered channel also required the addition
of another level spreader (P-14), for which a worksheet is also attached.
It is important to note that the proposed impacts for the project have not changed from the
original PCN application. All of the changes have been to stormwater controls, sediment
and erosion controls, lots, and a cul-de-sac with no additional impacts to jurisdictional
waters or riparian buffers.

Mr. Ian McMillan
February 28, 2007
Page 2 of 2
If you have any questions or require more information, please do not hesitate to contact
me at [phone].
Sincerely,
BURDETTE LAND CONSULTING, INC.
`.
Jenni er A. Burdette
Environmental Specialist
Attachments
c: Wayne Mauldin -Mauldin-Watkins Surveying
Alan Keith -Diehl & Phillips
Jamie Shern - US Army Corps of Engineers
Mike Horan - DWQ Raleigh Regional Office

Received 02 08 2007 16:58
02108/2007 15:56 919-467-5327 DIEHL & PHILLIPS PAGE 02
r ""^~~ 'r1 f i r rr r r rr r•- r r TRAN$1710N
1 r rR~y.~ ~~ j~r~y ~a ~ J ~ .iJ aaa JJ)~J ~' r 0 GRADE TO
~1 rr W. ~a"~~% r ~/. ~ ~ AJ d J 4r
1~ W` ~ y= ~r~a ~ ^ l J~'~~d~a J `~
y ~ ~ aar r ` I ' ~~ ~'
Yr~ .r- ~ ~' y ..~ ~ 4 d ` , y, ~, •.,-!:r" y, STA8ILIZEO
M..`-.. :°' f~i V / `''r' ,~r, -~ / SLOP
tea;., ~ Ott q ,„ l,/ .ar. • .ar. /r E
r~-y ~. MI"„'~p.~.u~~,l~ryrt''y/r Y/l``~` `~' .Ph~iy ~;r
M. r' "' ~• yr, yr, . yr, ` ~ _~ .~ y ..i. -aH ~• y,-N.
yry y!, y4 yr' 11r, yr, vr' yr~ ~~J ~~~ ~" ~'' ,y,'~v ,~ ~
_ yr, 114 yr' >I41y1i~4114 114 Vr ~) /~ ~ ~~u, ~,~" .y" ~'
iBED y411a r,li4 ~ yr, 11r,11r, 11411x, \ _ ~ y.d,, -xwy-air ~,,d,,
114 b4 yr, 114 114 11x, y4114 \~ \\ mow- ''"' ~ y,
11n y4114 yr, yr, 114 114 1141ir~v'' 114114\ ~ ~~\ ~"y,
114 114 y4 114 yyr' 114 yrllryr' yr, ~ -~
114 yr, yn y4 114 y41I4 yryr, 11x,
yr, yryr1/4 114 y4 114 llq yallr,yn yyr' y4
yryryr~ yr~frl yr' 114 y4 yr, 11x,
eD IN ~ ~-~-~-'
,~.~v ^ ~ 6" MIN
~~"'~r I I I I-_ - ~ I-I I I I
_I.~I I I=1 `III=1 I I=1 I- =- I I=1 I I=1 I'
III-III III-1 I Iil 11= I~ II I I~ I I I III-
~---- I I 1=1 11=
~--III 11=1 I I~-1 I I`-1 I I i l-1 11=1 i ICI I I--1 I I-~I
I---I ~-II I=1 I i-1 I I I I 1=III=1 I lil I I- 1=
-li iii-~~~---~~~ II~~I-,I~~~I~~_.._~~,III,,II
'EL LIP BURIEO
SPREADER 6"MIN
DETAIL OF LEVEL SPREADER CROSS SECTION.
CONST UCTION SPECIFICATIONS
1, THE MATTING SHOULD BE A MINIMUM OF 4 FT. WIDE EXTENDING 8 INCHES OVER THE LIP
AND @URIED B INCHES DEEP IN A VERTICAL TRENCH ON THE LOWER EDGE. THE UPPER
EDG SHOULD BUTT AGAINST SMOOTHLY CUT S00 AND BE SECURELY HELD IN PUCE WITH
CLO ELY SPACED HEAVY DUTY WIRE STAPLES AT (EAST 12 INCHES LONG.
2. ENS RE THAT THE SPREADER LIP IS LEVEL FOR UNIFORM SPREADING OF STORM RUNOFF.
3_ CON UCT THE LEVEL SPREADER ON UNDISTUR6ED SOIL (NOT ON FILL).
4. CON UCT A 20 FT TRANSITION SECTION FROM THE DIVERSION CHANNEL TO BLENO
SM THIY TO THE WIDTH AND DEPTH OF THE SPREADER.
5. DISP SE RUNOFF FROM THE SPREADER ACROSS A PROPERLY STABIUZEO SLOPE NOT
TO E CEED 10X. MAKE SURE THE SLOPE IS SUFFlCIENTLY SMOOTH TO KEEP FLOW FROM
CON ENTRATING_
8, IMMEC~VITELY AFTER ITS CONSTRUCTION, APPROPRIATELY SEED AND MULCH THE ENTIRE
GIST 9ED AREA OF THE SPREADER_
MAINTEHIANCE
INSPE LEVEL SPREADERS AFTER EVERY RAINFALL VNTIL
VEGET TION IS ESTABLISHED, AND PROMPTLY MAKE NEEDED REPAIRS. AFTER THE AREA
HAS EEN STABILIZED, MAKE PERIODIC INSPECTIONS AND KEEP vEGETAnoN IN A
HEALT VIGOROUS CONDITION.
LEVEL SPREADER
NOT TO SCALE

Received 02 08 2007 16 59
02/08/2607 15:56 919-467-5327 DIEHL & PHILLIPS PAGE 03
DWQ Project
o~-~qa.s
DMSION OF WATER QUALITY -LEVEL SPREAbER WORKSHEET
I. PROD C
Project Na
Contad Pe
Level Spree r
Level Spree
Drainage A
Impervious
Maximum F
grass
INFORMATION (please complete the
inforrnationl;
ID:- ~~~~~ SP2~~Ea ~ /~ S
I.sngth
Strip/Buffer Slope
ft.
ac.
x ~ ac.
3.S %
(perpendicular to flow)
(vn-site and off-site drainage 1n tl~e level spreader)
(on-site and off-site dralnage to the level spreader}
(li% for Forested, IeaF Ilttler rover, 894 for thick ground cover)'
Max. D from a 10 Year Storm ~,~ cFs
Mex. Dlsche a to Level Spreader B . A cfs
FIRer StripB r Vegetation ~~"~u ~c ~~ad~ (thick ground cover or grass, canopied forest with leaf Iltter
:_..... _ ..... _ ............... _ _.............. .:....._ ........ .... ..... .. - --- roundcover _ _ .. _-~-- - - - - - . .
~ti.. -
or Bypass Method Nli~
II. REOUI(tED ITEMS CHECKLIST
Initial in the s oe provided m indicate the following design requirements have been met and supporting documentation is attached. If a
requirement es not been met, altacb an expfanalivn of why. At a minimum, a complete storrnwater management plan submlttal Indudes
a worksheet or each BMP, design calculations, plans and spedflcadons showing all BMPs and outlet sUudure details, a detailed
drainage plc and a fully executed operation and malntenenc~ agreement An incomplete submittal package will result in a request for
additional in nnation and witl substantially delay final review and approval of the project
spreader is at least 13 R per cis for thick ground cover or grass or 100 ft per cfs in canopied forest with leaf
litter.
Pre-Form Scour Holes are on flat slopes only
No structures are located in protected butters'
If bypass
specified in the Draft Level Spreader Design Option Document
Bypass meU~od is spedfied (if applicable) and plan details and calculations are provided
Disct-ange to level spreader and subsequent filter ship is hydreulically and spatiatly separate From the bypass
discharge.
No sbudures are located in protected butters_
Plan details for the bypass and outlets are provided.
The operation and mainterranoe agreement inductee annual erosion and vegetation repair.
The operation and maintenance agreement signed and notarized by the responsible party is provided.
• Level spre ere in series can be used on slopes of up to 15% in forested areas with leaf littler cover or on slopes of up to 2596 in areas
with (hide gro nd Dover or grass 'rf designed aocording to the Draft Levet Spreader Design Option Document. This potentially requires a
minor verian in protected buffer areas. In any event the second level spreader cannot be located in Zone 1 of a protected buffer area.

Received 02 26 2007 12:23
Et2126/2DD? 11:213 919-46?-532? DIEHL & PHILLIPS PAGE D2
awQ Project
DIVISION OF WATER QUALITY -LEVEL SPREAbER WORKSHEET
[. PROJECT INFORMATION (please co plate the following information):
Project Name
Contact pin; Phone Number.
Level Spreader ID:. L-~UrL. SPR.CAI~~j~- t~ '~ 1'~'
Level Spreader Length f ,~ ft. (perpendicular to flow)
Drainage Area ac. (on-site and off-site drainage to the level spreader)
Impervious Area ~~ ac. (on-site and off-site drainage to the Level spreader)
Maximum Etter StripJBuffer Slope 4. ~ % {6% for forested, leaf littler cover, B% for thick ground cover)'
grass
Max. Discharge cram a 10 Year Storm `~'~ ~ cfs
Max. discharge b Level Spreader ^ '~"~ ds
Filter StriplBuffer Vegetation T~~~. ~1J (thick ground cover or grass, canopied forest with leaf litter
ronn cover _._-.-_.----. _--_ _.__--__._--.- __
Pre-treatment or Bypass Method 11.1/W
!l. REQUIRED ITEMS CHECIQ.IST
Initial in the space provided b indicate the idiowing design requirements have been met and supporting documentation is attached. tf a
n3quin:merrt has not been meG attach an exptanaGon of why. At a minimum, a complete sbmrwater management plan submittal indudes
a worksheet for each BMP, design calculations, plans and spedficafions showing all BMPs and outlet sinx:Wre details, a detailed
drainage plan and a fully executed operation and maintenance agreement. An incomplete submittal package wrll result in a request for
additional information and vwTl substmrtialty delay float review and approval of the project.
Aanticants Initials
~,df!L _ l.,evel spreader is at least 13 ft. per efs for thick ground cover or grass or 100 tt per cfs in canopied forest with leaf
titter.
N/f~ ___ _Pn~-Farm Scour Notes are on flat slopes only
_. A~.rc., No structures are loca#ed in protected buffers'
If bypass method speafied in the Draft Level Spreader Design Option DocumenE
Bypass method is specified (rf applicable) and plan details and cak~lations are pnnrided
Disd~arge b level spreader and subsequent fitter strip is hydraulically. and spatially separate from the bypass
discharge.
No struchrres are located in protected buffers.
Plan details for the bypass and outtefs are provided.
The operation and maintenance agreement tndudes annual erasion and vegetation repair.
The operation and maintenance agreement signed and natarixed by the responsible party is provided.
Level spreaders in series can be used on slopes of up to 1596 in forested areas with leaf iitfler saver or on slopes of up to 25% in areas
with thick ground cover or grass 'rf designed according to the Draft Level Spreader Design dptian Document. This potentially requires a
minor variance in protected butler areas. In any event the second level spreader cannot be located in Zone 1 of a protected buffer area.

LEVEL SPREADER OPERATION AND MAINTENANCE AGREEMENT
{P-5, P-11, P-14, P-21, & P-25)
The level spreader is defined as an elongated, level threshold, designed to diffuse stormwater runoff.
Maintenance activities shall be performed as follows:
1. After construction and until vegetation has been established, level spreader(s) shall be inspected after
every rainfall. Thereafter, level spreader(s) shall be inspected at /easf every month and more
frequently during the fall season and after heavy rainfall events:
a. Accumulated sediment, leaves, and trash shall be removed, and repairs made if required.
b. Inspect level spreader(s) for evidence of scour, undercutting, settlement of the structure, and
concentrated flows downhill from the level spreader(s).
c. A level elevation shall be maintained across the entire flow-spreading structure at all times.
Repair or replace the level spreader if it is damaged.
d. Mow vegetative cover to a height of six (6) inches and prune plants if they cover over half of the
level spreader surface.
e. Repair eroded areas and replace/replant dead or damaged vegetation.
2. The contractor should avoid the placement of any material on and prevent construction traffic across
the structure. If the measure is damaged by construction traffic, it shall be repaired immediately.
3. Inspect and repair the collection system (e.g., catch basins, pipes, swales, riprap) four (4) times a year
to maintain proper functioning.
I acknowledge and agree by my signature below that I am responsible for the performance of the maintenance
procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to
the system or responsible pasty.
Print name;
{ Ue ~e/i~er1'
Title: t
Address: /1071 ~lOaKS~ilre D~

Note: The legally responsible party should not be a homeowners association unless more than 50% of the
lotsfiave been sold and a resident of the subdivision has been named the president. .
,. ~,
1, _~~ , a Notary Public fort a State of ~~~~y 1~-y/~
County of , do hereby certify that ,~fG
personally appeared before me this ~'r day of , a~, and ac ledge the/d/u/e
execution of the forgoing wet [wetland] detention basin maintenanc~fequirements. Witness my hand and
official seal,
~`~°.e`v` Y AQ e~°ev
e~°•J~GVC ......4 4~'~
r ~ ~''~ ~
;" NOTARY i
_~: ~** _~
~s PUBLIC i
r
`9~ ~' V
'1A°0ee1p ~aO ~l jj ~n-~~~```~``a`s
SEAL
My commission expires / ~/
Page 1 of 1