SW8060511_COMPLIANCE_20061113

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW�j
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
Fy COMPLIANCE EVALUATION INSPECTION
DOC DATE
(1�
YYYYM M DD

Permit No. SN$ o(Cosri
(to be provider! by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION 1~ORNI
UNDERGROUND INFILTRATION TRENCH SUPPLEMENT
This form may he photocopied for use as at? original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
underground infiltration trench supplement for each system, design calculations, and plans and specifications
showing all stormwater conveyances and system details.
L PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE Phone Number: 910-343-1048
For projects with multiple infiltration systems, a supplement form must be completed for each system. This worksheet
applies to:
Trench 1 In Drainage Area 1
(from plans) (from Form SWU-101)
11. DESIGN INFORMATION (attach supporting calculations/documentation):
Soils Report Summary (based upon an actual field investigation and soil borings)
Soil Type Baymeade
Infiltration Rate 23 Ed or cUhr/sf (circle appropriate units)
SHWT Elevation 48.0 fmsl (Seasonal High Water Table elevation)
Trench Design Parameters
Design Volume
12,023
c.f.
Design Storrn
3
inch event (1.5 inch event for SA waters, I inch event for others)
Drawdown Time
0.061
days
Perforated Pipe Size
36
inch diameter
Perforated Pipe Length
1,440
ft.
No. Observation Wells
24
(may be required on a case -by -case basis)
Stone Type (if used)
#57
Stone Void Ratio
0.4
Trench Elevations (in feet mean sea level)
Bottom Elevation
50.0
frrtsl
Storage/Overflow Elevation NA lowest rim el. = 54.2 fmsl
Form SW U-107 Rev 3.99 Page 1 of 4

Trench Dimensions
Height 3.5 ft. Length 240 ft.
Width 36 ft. Volume Provided 18,203 cuff
III. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices manual (N.C.
Department of Environment, Health and Natural Resources, November 1995) and Administrative Code Section: 15
A NCAC 2H .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
"W a. System is located 50 feet from class SA waters and 30 feet from other surface waters.
b. System is located at least 100 feet from water supply wells.
c. Bottom of system is at least 2 feet above the seasonal high water table.
r. d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
N/ e. Off-line system, runoff in excess of the desi n volumeebpasse,; the system (bypass detail
provided). 2.4'1no%i5ow e�1�'•e%eM)
f. System is designed to draw down the design storage volume to the proposed bottom
elevation under seasonal high water conditions within five days based upon infiltration
through the bottom only (a hydrogeologic evaluation may be required).
C► g. Soils have a minimum hydraulic conductivity of 0.52 inches per hour.
h. System is not sited on or in fill material or DWQ approval has been obtained.
i. Plans ensure that the installed system will meet design specifications (constructed or
restored) upon initial operation once the project is complete and the entire drainage area is
G stabilized.
j. System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage.
G k. System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way.
I. System captures and infiltrates the runoff from the first 1.0-inch of rainfall (1.5 inch event
W.e for areas draining to SA waters).
m. Drainage area for the device is less than 5 acres.
n. A pretreatment device (filter strip, grassed swale, sediment trap, etc.) is provided.
o. Trench bottom is covered with a layer of clean sand to an average depth of 4 inches.
I�InG p. Sides of the infiltration trench are lined with geotextile fabric.
q. Rock used is free of fines (washed stone) and has a large void ratio.
—G r. Side to bottom area ratio is less than 4: l .
Form SWU-107 Rev 3.99 Page 2 of 4

Aw-es. Observation well(s) are provided (case -by -case basis).
N/� t. Vegetated filter is provided for overflow (50 feet for SA waters, 30 feet for other waters)
and detail is shown on plans.
i00,i u. A benchmark for checking sediment accumulation is provided.
IV. UNDERGROUND INFILTRATION TRENCH OPERATION AND MAINTENANCE AGREEMENT
1. After every runoff producing rainfall event and at least monthly inspect the bypass/overflow structure for
blockage and deterioration and the infiltration system for erosion, trash accumulation, grass cover, and general
condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and remove trash and blockages as needed to maintain system
performance.
Remove accumulated sediment annually or when depth is reduced to 75% of the original design depth. Restore
depth to original design depth without over -excavating. Over -excavating may cause the required water table
separation to be reduced and may compromise the ability of the system to perform as designed.
4. The water level in any monitoring wells will be recorded after a 1-inch rainfall event and at least once a month.
Chronic high water table elevations (within I foot of the bottom of the system for a period of three months) shall
be reported to DWQ immediately.
5. If DWQ determines that the system is failing, the system will immediately be repaired or replaced to original
design specifications. if the system cannot be repaired to perform its design function, other stormwater control
devices as allowed by NCAC 21­1 .1000 must be designed, approved and constructed.
6. Remove accumulated sediment from the infiltration system annually or when depth in the unit is reduced to
75% of the original design depth. The system shall be restored to the original design depth without over
excavating. Over -excavating may cause the required water table separation to be reduced and may
compromise the ability of the system to perform as designed. Removed sediment shall be disposed of in an
appropriate manner and shall not be handled in a manner that will adversely impact water quality (i.e.
stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the infiltration system. The benchmark will document the original
design depth so that accurate sediment accumulation readings can be taken. The measuring device used to
determine the depth at the benchmark shall be such that it will give an accurate depth reading and not
readily penetrate into accumulated sediments.
When the depth at the benchmark reads NIA , the accumulated sediment shall be removed
from the system.
Form SWU-107 Rev 3.99 Page 3 of 4

t, acknowledge and agree by my signature below that I am responsible for maintaining the stormwater collection
system in accordance with the six 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 party.
Print name: Mark Raaozzino
TitEe: Managing, Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone]
Signature: �'1L—j
Date:
Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a
resident of the subdivision has been named the president.
f, t SO as Notary Public for the State of 67 f Lhounty of
O0e;r , do hereby certify that Aka r-i, aay-LZ [t)o personally appeared before me this
i S4� day of s'�' , a0O4 and acknowledge the due execution of the forgoing infiltration
basin maintenance requirements. Witness my hand and official seal,
- ma`'',
0
pTArq
QtF�L� My commission expires
VI:� aata�``
llllllll1aa
Form SWU-107 Rev 3,99 Page 4 of 4

T ` Permit No. 5W X d Cp0 S 1(
(to be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
UNDERGROUND INFILTRATION TRENCH SUPPLEMENT
This for n may be photocopied for use as can original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
underground infiltration trench supplement for each system, design calculations, and plans and specifications
showing all stormwater conveyances and system details.
1. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE Phone Number: 910-343-1048
For projects with multiple infiltration systems, a supplement form must be completed for each system. This worksheet
applies to:
Trench 2 In Drainage Area 2
(frown plans) (from Form SaVU-10/)
IL DESIGN INFORMATION (attach supporting calculations/documentation):
Soils Report Summary (based upon an actual field investigation and soil borings)
Soil Type Mandarin / Baymeade
Infiltration Rate 23 in or ef/hr/Sf (circle' appropriate units)
SHWT Elevation 48.0 fmsl (Seasonal High Water Table elevation)
Trench Design Parameters
Design Volume
20,010
c.f.
Design Storm
3
inch event (1.5 inch eventfor SR waters, 1 inch event for others)
Drawdown Time
0.075
days
Perforated Pipe Size
36
inch diameter
Perforated Pipe Length
1,925
ft.
No. Observation Wells
42
(nary be required on a case -by -case basis)
Stone Type (if used)
#57
Stone Void Ratio
0.4
Trench Elevations (inn feet mean sea level)
Bottom Elevation
50.0
fms]
Storage/Overflow Elevation NA lowest rim el. = 53.9 fmsl
Form SWU-107 Rev 3.99 Page 1 of 4

Trench Dimensions
Height 3.5 fi. Length 275 ft.
Width 42.0 It. Volume Provided 24,334 cu.ft.
III. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices manual (N.C.
Department of Environment, Health and Natural Resources, November 1995) and Administrative Code Section: 15
A NCAC 2H .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
a.
b.
C.
d,
C.
System is located 50 feet from class SA waters and 30 feet from other surface waters.
System is located at least 100 feet from water supply wells.
Bottom of system is at least 2 feet above the seasonal high water table.
Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
Off-line system, runoff in excess of the design volume bypasses the system (bypass detail
provided). 3. Q"600Y.-T C,�i •Wid
System is designed to draw down the design storage volume to the proposed bottom
elevation under seasonal high water conditions within five days based upon infiltration
through the bottom only (a hydrogeologic evaluation may be required).
Soils have a minimum hydraulic conductivity of 0.52 inches per hour.
System is not sited on or in fill material or DWQ approval has been obtained.
i. Plans ensure that the installed system will meet design specifications (constructed or
restored) upon initial operation once the project is complete and the entire drainage area is
stabilized.
,A ` J. System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage.
k. System is located in a recorded drainage easement for the puIposes of operation and
maintenance and leas recorded access casements to the nearest public right-of-way.
1. System captures and infiltrates the runoff from the first 1.0-inch of rainfall (1.5 inch event
for areas draining to SA waters).
- m. Drainage area for the device is less than 5 acres.
n. A pretreatment device (filter strip, grassed swale, sediment trap, etc.) is provided.
o. Trench bottom is covered with a layer of clean sand to an average depth of 4 inches.
p. Sides of the infiltration trench are lined with geotextile fabric.
q. Rock used is free of fines (washed stone) and has a large void ratio.
r. Side to bottom area ratio is less than 4:1.
Form SWU-107 Rev 3.99 Page 2 of 4

/ZI s. Observation well(s) are provided (case -by -case basis).
t. Vegetated filter is provided for overflow (50 feet for SA waters, 30 feet for other waters)
and detail is shown on plans.
u. A benchmark for checking sediment accumulation is provided.
IV. UNDERGROUND INFILTRATION TRENCH OPERATION AND MAINTENANCE AGREEMENT
1. After every runoff producing rainfall event and at least monthly inspect the bypass/overflow structure for
blockage and deterioration and the infiltration system for erosion, trash accumulation, grass cover, and general
condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and remove trash and blockages as needed to maintain system
performance.
3. Remove accumulated sediment annually or when depth is reduced to 75% of the original design depth. Restore
depth to original design depth without over -excavating. Over -excavating may cause the required water table
separation to be reduced and may compromise the ability of the system to perform as designed.
4. The water level in any monitoring wells will be recorded after a 1-inch rainfall event and at least once a month.
Chronic high water table elevations (within 1 foot of the bottom of the system for a period of three months) shall
be reported to DWQ immediately.
5. If DWQ determines that the system is failing, the system will immediately be repaired or replaced to original
design specifications. if the system cannot be repaired to perform its design function, other stormwater control
devices as allowed by NCAC 21-1 .1000 must be designed, approved and constructed.
6. Remove accumulated sediment from the infiltration system annually or when depth in the unit is reduced to
75% of the original design depth. The system shall be restored to the original design depth without over
excavating. Over -excavating may cause the required water table separation to be reduced and may
compromise the ability of the system to perform as designed. Removed sediment shall be disposed of in an
appropriate manner and shall not be handled in a manner that will adversely impact water quality (i.e.
stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the infiltration system. The benchmark will document the original
design depth so that accurate sediment accumulation readings can be taken. The measuring device used to
determine the depth at the benchmark sliall be such that it will give an accurate depth reading and not
readily penetrate into accumulated sediments.
When the depth at the benchmark reads NIA , the accumulated sediment shall be removed
from the system.
Form SWU-107 Rev 3.99 Page 3 of 4

i acknowledge and agree by my signature below that I am responsible for maintaining the stormwater collection
system in accordance with the six maintenance procedures listed above. 1 agree to notify DWQ of any problems
with the systern or prior to any changes to the system or responsible party.
Print name: Mark Ra ozzino
Title: Managing Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone]
Signature: "_�.j
Date: x l k� 10
Note: The legally responsible party should not be a homeowners association unless n:ore than 50% of the lots have been sold and a
resident of the subdivision has been named the president.
1, rd Lk., e, CAI EONS , a Notary Public for the State of county of Moo
Q `h?iOV do hereby certifyr that r 1[Q� ZZ1 Np personally appeared before me this
S�k day of t ')DOLo ,and acknowledge the due execution of the forgoing infiltration
ki
basin maintenance requirements. Witness my hand and official seal,
p„u 11 F1 rp",/
y�
TA�y n
y /t7 - My commission expires o3 J 10 �i
+rrroili�r,
Form SWU-107 Rev 3.99 Page 4 of 4

Permit No. s(N F0CPo5l r
(io be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
UNDERGROUND INFILTRATION TRENCH SUPPLEMENT
This form may be photocopier) for use as an original
DWQ Storinwater Management Plan Review -
A complete stormwater management plan submittal includes a stormwater management permit application, an
underground infiltration trench supplement for each system, design calculations, and plans and specifications
showing all stormwater conveyances and system details.
I. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE Phone Number: 910-343-1048
For projects with multiple infiltration systems, a supplement form must be completed for each system. This worksheet
applies to:
Trench 3A In Drainage Area 3A
(from plans)
(from Form SWU-101)
II. DESIGN INFORMATION (attach supporting calculations/documentation):
Soils Report Summary (based upon an actual field investigation and ,roil borings)
Soil Type Mandarin / Baymeade
Infiltration Rate 23 in/h or cflhrlsf (circle appropriate units)
SHWT Elevation 48.0 fmsl (Seasonal High Water Table elevation)
Trench Design Parameters
Design Volume
6,621
c.f.
Design Storm
3
inch event (I,S inch event for SA waters, 1 inch event for others)
Drawdown Time
0.063
days
Perforated Pipe Size
42
inch diameter
Perforated Pipe Length
195
ft.
No. Observation Wells
0
(may be required on a case -by -case basis)
Stone Type (if used)
#57
Stone Void Ratio
0.4
Trench Elevations (in feet meal)
sea level)
Bottom Elevation
50.0
fins]
Storage/Overflow Elevation NA lowest rim el. = 54.1 fmsl
Form SWU-107 Rev 3.99 Page 1 of 4

Trench Dimensions
Height 4.13 ft. Length 195 ft.
Width 23.5 ft. Volume Provided 8,687 cu.ft.
111. REQUIRED ITEMS ClTECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices manual (N.C.
Department of Environment, Health and Natural Resources, November 1995) and Administrative Code Section: 15
A NCAC 2H .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Dorm, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
a.
b.
C.
rr d.
�V f.
[,��
0 rw 9.
46 h.
System is located 50 feet from class SA waters and 30 feet from other surface waters.
System is located at least 100 feet from water supply wells.
Bottom of system is at least 2 feet above the seasonal high water table.
Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
Off-line system, runoff in excess of the design volume bypasses the system (bypass detail
67 provided). *ItOT 14(Lo
System is designed to draw down the design storage volume to the proposed bottom
elevation under seasonal high water conditions within five days based upon infiltration
through the bottom only (a hydrogeologic evaluation may be required).
Soils have a minimum hydraulic conductivity of 0.52 inches per hour.
System is not sited on or in fill material or DWQ approval has been obtained.
Plans ensure that the installed system will meet design specifications (constructed or
restored) upon initial operation once the project is complete and the entire drainage area is
stabilized.
System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage.
k. System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way,
1. System captures and infiltrates the runoff from the first 1.0-inch of rainfall (1.5 inch event
for areas draining to SA waters).
h/ m. Drainage area for the device is less than 5 acres.
n. A pretreatment device (filter strip, grassed swale, sediment trap, etc.) is provided.
o. Trench bottom is covered with a layer of clean sand to an average depth of 4 inches.
p. Sides of the infiltration trench are lined with geotextile fabric.
q. Rock used is free of fines (washed stone) and has a large void ratio.
r. Side to bottom area ratio is less than 4:1.
Form SWU-107 Rev 3.99 Page 2 of 4

s. Observation well(s) are provided (case -by -case basis).
t. Vegetated filter is provided for overflow (50 feet for SA waters, 30 feet for other waters)
and detail is shown on plans.
' u. A benchmark for checking sediment accumulation is provided.
IV. UNDERGROUND INFILTRATION TRENCH OPERATION AND MAINTENANCE AGREEMENT
1. After every runoff producing rainfall event and at least monthly inspect the bypass/overflow structure for
blockage and deterioration and the infiltration system for erosion, trash accumulation, grass cover, and general
condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and remove trash and blockages as needed to maintain system
performance.
3. Remove accumulated sediment annually or when depth is reduced to 75% of the original design depth. Restore
depth to original design depth without over -excavating. Over -excavating may cause the required water table
separation to be reduced and may compromise the ability of the system to perform as designed.
4. The water level in any monitoring wells will be recorded after a 1-inch rainfall event and at least once a month.
Chronic high water table elevations (within 1 foot of the bottom of the system for a period of three months) shall
be reported to DWQ immediately.
5. If DWQ determines that the system is failing, the system will immediately be repaired or replaced to original
design specifications. If the system cannot be repaired to perform its design function, other stormwater control
devices as allowed by NCAC 21-1 .1000 must be designed, approved and constructed.
6. Remove accumulated sediment from the infiltration systern annually or when depth in the unit is reduced to
75% of the original design depth. The system shall be restored to the'original design depth without over
excavating. Over -excavating may cause the required water table separation to be reduced and may
compromise the ability of the system to perform as designed. Removed sediment shall be disposed of in an
appropriate manner and shall not be handled in a manner that will adversely impact water quality (i.e.
stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the infiltration system. The benchmark will document the original
design depth so that accurate sediment accumulation readings can be taken. The measuring device used to
determine the depth at the benchmark shall be such that it will give an accurate depth reading and not
readily penetrate into accumulated sediments.
When the depth at the benchmark reads NIA , the accumulated sediment shall be removed
from the system.
Form SWU-107 Rev 3.99 Page 3 of 4

• itcknowledge and agree by my signature below that I am responsible for maintaining the stormwater collection
system in accordance with the six 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 party.
Print name: Mark RaLozzino
Title: Managing Member
Address: The Commons at Calabash LLC, 234_Sea Gull Lane`Wilmitlgto 1,_NC_28409___
Phone: [phone]
Signature:-'
Date: tt\ D
Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a
resident of the subdivision has been named the president.
I, _ i SOIL a Notary Public for the State of Nlor-4 111,11;)County ofPO
L38T- do hereby certify that fkaf rJD personally appeared before me this
l day of , Zd1)CO , and acknowledge the due execution of the forgoing infiltration
basin maintenance requirements. fitness my hand and official seal,
0
0�t44111114/���,,
IOTA
Y
B - My conunission expires
mW
Form SWU-107 Rev 3.99 Page 4 of 4

Peiimt No. SGu go&ost f
(to be provided by 1)fYQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
UNDERGROUND INFILTRATION TRENCH SUPPLEMENT
This form may be photacopied for use as an original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
underground infiltration trench supplement for each system, design calculations, and plans and specifications
showing all stormwater conveyances and system details.
1. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE Phone Number: 910-343-1048
For projects with multiple infiltration systems, a supplement form must be completed for each system. This worksheet
applies to:
'French 9 In Drainage Area 9
(front plans) (from Form SWU-101)
11. DESIGN INFORMATION (attach supporting calculations/documentation):
Soils Report Summary (based upon an actual field investigation and soil borings)
Soil Type Mandarin / Leon
Infiltration Rate 23 Fin7q or cf/hr/sf (circle appropriate units)
SH WT Elevation 48.0 fmsl (Seasonal High Water Table elevation)
Trench Design Parameters
Design Volume
7,242
c.f.
Design Storm
3
inch event (1.5 inch event for SR waters, 1 inch event for others)
Drawdown Time
0.087
days
Perforated Pipe Size
36
inch diameter
Perforated Pipe Length
520
ft.
No. Observation Wells
8
(nary be required on a case -by -case basis)
Stone Type (if used)
#57
Stone Void Ratio
0.4
Trench Elevations (in feet mean sea level)
Bottom Elevation
50.0
fmsl
Storage/Overflow Elevation NA lowest rim el. = 55.0 fmsl
Form SWU-107 Rev 3.99 Page 1 of 4

:-/
Trench Dimensions
Height 3.5 ft. Length 130 ft.
Width 28 ft. Volume Provided 7,301 cu.ft.
III. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices manual (N.C.
Department of Environment, Health and Natural Resources, November 1995) and Administrative Code Section: 15
A NCAC 211 .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Bonn, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
P,(� a. System is located 50 feet from class SA waters and 30 feet from other surface waters.
7 b. System is located at least 100 feet from water supply wells.
c. Bottom of system is at least 2 feet above the seasonal high water table.
1� d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
e. Off-line system, runoff in excess of the design volume bypasses the system (bypass detail
provided).
f. System is designed to draw down the design storage volume to the proposed bottom
elevation under seasonal high water conditions within five days based upon infiltration
through the bottom only (a hydrogeologic evaluation may be required).
/ g. Soils have a minimum hydraulic conductivity of 0.52 inches per hour.
h. System is not sited on or in fill material or DWQ approval has been obtained.
i. Plans ensure that the installed system will meet design specifications (constructed or
restored) upon initial operation once the project is complete and the entire drainage area is
stabilized.
y� j. System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off=site drainage.
k. System is located in a recorded drainage casement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way.
System captures and infiltrates the runoff from the first 1.0-inch of rainfall (1.5 inch event
for areas draining to SA waters).
Drainage area for the device is less than 5 acres.
A pretreatment device (filter strip, grassed swale, sediment trap, etc.) is provided.
Trench bottom is covered with a layer of clean sand to an average depth of 4 inches.
Sides of the infiltration trench are lined with geotextile fabric.
Rock used is free of fines (washed stone) and has a large void ratio.
Side to bottom area ratio is less than 4:1.
Form SWU-107 Rev 3.99 Page 2 of 4

i s. Observation well(s) are provided (case -by -case basis).
t. Vegetated filter is provided for overflow (50 feet for SA waters, 30 Feet for other waters)
and detail is shown on plans.
u. A benchmark for checking sediment accumulation is provided.
IV. UNDERGROUND INFILTRATION TRENCH OPERATION AND MAINTENANCE AGREEMENT
1. After every runoff producing rainfall event and at least monthly inspect the bypass/overflow structure for
blockage and deterioration and the infiltration system for erosion, trash accumulation, grass cover, and general
condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and remove trash and blockages as needed to maintain system
performance.
3. Remove accumulated sediment annually or when depth is reduced to 75% of the original design depth. Restore
depth to original design depth without over -excavating. Over -excavating may cause the required water table
separation to be reduced and may compromise the ability of the system to perform as designed.
4. The water level in any monitoring wells will be recorded after a 1-inch rainfall event and at least once a month.
Chronic high water- table elevations (within 1 foot of the bottom of the system for a period of three months) shall
be reported to DWQ immediately.
5. If DWQ determines that the system is failing, the system will immediately be repaired or replaced to original
design specifications. If the system cannot be repaired to perform its design function, other stormwater control
devices as allowed by NCAC 21-1 .1000 must be designed, approved and constructed.
G. Remove accumulated sediment from the infiltration system annually or when depth in the unit is reduced to
75% of the original design depth. The system shall be restored to the original design depth without over
excavating. Over -excavating may cause the required water table separation to be reduced and may
cornprornise the ability of the system to perform as designed. Removed sediment shall be disposed of in an
appropriate manner and shall not be handled in a manner that will adversely impact water quality (i.e.
stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the infiltration system. The benchmark will document the original
design depth so that accurate sediment accumulation readings can be taken. The measuring device used to
determine the depth at the benchmark shall be such that it will give an accurate depth reading and not
readily penetrate into accumulated sediments.
When the depth at the benchmark reads NIA , the accumulated sediment shall be removed
from the system.
Form SWU-107 Rev 3.99 Page 3 of 4

'Y I acknowledge and agree by my signature below that l am responsible for maintaining the storrnwater collection
• system in accordance with the six 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 party.
Print name: Mark Ragozzino
Title: Manaeina Member
Address: The Commons at Calabash LLCM 234 Sea Gull Lane, Wilmington, NC 28409����
Phone: [phone]
Signature:
Date:��-
Note.- The legally responsible parry should not be a homeowners association unless more than 50% of the lots have been sold and a
resident of the subdivision has been named the president.
I, (�. { a Notary Public for the State of 6"&24A County of New
r W;4j do hereby certify that ZM j4V U personally appeared before me this
1 S4'�%, day of 't- aDb[p and acknowledge the due execution of the forgoing infiltration
basin maintenance requirements. Witness my hand and official seal,
�pTAq�,
G �� ���
y� I1 � My commission expires _ _0q
"NOVO-
41+il111 [ IAA
Form SWU-107 Rev 3.99 Page 4 of 4

Permit No. 56k) '5GCPO Sf 1
(to be provided by DW(Q)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
UNDERGROUND INFILTRATION TRENCH SUPPLEMENT
This fornr nroy be photocopied for use as an original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
underground infiltration trench supplement for each system, design calculations, and plans and specifications
showing all stormwater conveyances and system details.
I. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE Phone Number: 910-343-1048
For projects with multiple infiltration systems, a supplement form must be completed for each system. This worksheet
applies to:
Trench 9A In Drainage Area 9A
(from plans) (from Form SrVU-101)
II. DESIGN INFORMATION (attach supporting calculations/documentation):
Soils Report Summary (based upon (rn actual field investigation and soil borings)
Soil Type Mandarin
Infiltration Rate 23 in/ or cf/hr/sf (circle appropriate units)
SFIWT Elevation 48.0 fmsl (Seasonal High Water Table elevation)
Trench Design Parameters
Design Volume
5,587
c.f.
Design Storm
3
inch event (1.5 inch event for SA waters, I inch event for others)
Drawdown Time
0.083
days
Perforated Pipe Size
36
inch diameter
Perforated Pipe Length
420
ft.
No. Observation Wells
12
(lnay be required on a case-bj,-case basis)
Stone Type (if used)
#57
Stone Void Ratio
0.4
Trench Elevations (in feet mean sea level)
Bottom Elevation
50.0
fmsl
Storage/Overflow Elevation NA (Double Storage) fmsl
Form SWU-107 Rev 3.99 Page 1 of 4

Trench Dimensions.
Height 3.5 ft. Length 70 ft.
Width 42 ft. Volume Provided 5,897 cu.ft.
III. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices manual (N.C.
Department of Environment, Health and Natural Resources, November 1995) and Administrative Code Section: 15
A NCAC 2H .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. if the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
0 a_ System is located 50 feet from class SA waters and 30 feet from other surface waters.
b. System is located at least 100 feet from water supply wells.
c. Bottom of system is at least 2 feet above the seasonal high water table.
d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
e. Off-line system, runoff in excess of the design volume bypasses the system (bypass detail
provided).
f. System is designed to draw down the design storage volume to the proposed bottom
elevation under seasonal high water conditions within five days based upon infiltration
through the bottom only (a hydrogeologic evaluation may be required).
g. Soils have a minimum hydraulic conductivity of 0.52 inches per hour.
h. System is not sited on or in fill material or DWQ approval has been obtained.
Plans ensure that the installed system will meet design specifications (constructed or
restored) upon initial operation once the project is complete and the entire drainage area is
stabilized.
System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage.
k. System is located in a recorded drainage easement for the purposes of operation and
�K! maintenance and has recorded access easements to the nearest public right-of-way.
M f 1. System captures and infiltrates the runoff from the first 1.0-inch of rainfall (1.5 inch event
for areas draining to SA waters).
m. Drainage area for the device is less than 5 acres.
n. A pretreatment device (filter strip, grassed swale, sediment trap, etc.) is provided.
o. 'french bottom is covered with a layer of clean sand to an average depth oi'4 inches.
j p. Sides of the infiltration trench are lined with geotextile fabric.
q. Rock used is free of fines (washed stone) and has a large void ratio.
r. Side to bottom area ratio is less than 4:1.
Form SWU-107 Rev 3.99 Page 2 of 4

:i
s. Observation well(s) are provided (case -by -case basis).
t. Vegetated filter is provided for overflow (50 feet for SA waters, 30 feet for other waters)
and detail is shown on plans.
i u. A benchmark for checking sediment accumulation is provided.
IV. UNDERGROUND INFILTRATION TRENCH OPERATION AND MAINTENANCE AGREEMENT
1. After every runoff producing rainfall event and at least monthly inspect the bypass/overflow structure for
blockage and deterioration and the infiltration system for erosion, trash accumulation, grass cover, and general
condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and remove trash and blockages as needed to maintain system
performance.
Remove accumulated sediment annually or when depth is reduced to 75% of the original design depth. Restore
depth to original design depth without over -excavating. Over -excavating may cause the required water table
separation to be reduced and may compromise the ability of the system to perform as designed.
4. The water level in any monitoring wells will be recorded after a 1-inch rainfall event and at least once a month.
Chronic high water table elevations (within f foot of the bottom of the system for a period of three months) shall
be reported to DWQ immediately.
5. If DWQ determines that the system is failing, the system will immediately be repaired or replaced to original
design specifications. If the system cannot be repaired to perform its design function, other stormwater control
devices as allowed by NCAC 21-I .1000 must be designed, approved and constructed.
6. Remove accumulated sediment from the infiltration system annually or when depth in the unit is reduced to
75% of the original design depth. The system shall be restored to the original design depth without over
excavating. Over -excavating may cause the required water table separation to be reduced and may
compromise the ability of the system to perform as designed. Removed sediment shall be disposed of in an
appropriate manner and shall not be handled in a manner that will adversely impact water quality (i.e.
stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the infiltration system. The benchmark will document the original
design depth so that accurate sediment accumulation readings can be taken. The measuring device used to
determine the depth at the benchmark shall be such that it will give an accurate depth reading and not
readily penetrate into accumulated sediments.
When the depth at the benchmark reads NIA , the accumulated sediment shall be removed
from the system.
Form SWU-107 Rev 3.99 Page 3 of 4

I acknowledge and agree by my signature below that I am responsible for maintaining the stonnwater collection
systern in accordance with the six maintenance procedures listed above. I agree to noti Fy D WQ of any problems
with the system or prior to any changes to the system or responsible party.
Print name: Mark Ragozzino
Title: Managing Member
Address: The Commons at Calabash LLC, 2.34 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone]
Signature:
Date
--OLJ(
0ff-I
Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a
resident of the subdivision has been named the president.
1 I(1G� j °� -,a Notary Public for the State of Nt>kJ-karDj;r%k-.•bounty of NP k1
►v�E do hereby certify that Xrf-k PjO40 z7-r NU personally appeared before me this
S-i-� day of cwo4b and acknowledge the due execution of the forgoing infiltration
basin maintenance requirements. Witness my hand and official seal,
,tµtltnurp,,,
LG _ My commission expires �.3 f ) 4I�
A
UN
.,ko
,,!'
Form 5WU-107 Rev 3.99 Page 4 of 4

Permit No. —<�&) L'TOG'05 I
(to be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of 'Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
INFILTRATION BASIN SUPPLEMENT
This form may be photocopied far use as an original
DWQ Stormwater Management__l'lan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications showing
all stormwater conveyances and system details.
I. PROJECT INFOR-NMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE
This worksheet applies to: Basin No
IA
(as identifier) on plans)
Phone Number:
in Drainage Area
10)343-1048
I
(front Form SWU-101)
II. DESIGN INFORMATION — Attach supporting calculations / documentation. The soils report must be based upon an
actual field investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean seal level (fms]).
Soils Report Summary
Soil 'Type
Infiltration Rate
SHWT Elevation
Basin Design Parameters
Design Storm.
Design Volume
Drawdown Time
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
Top Elevation
Baymeade
23 in/h or cf/hr/sf (circle appropriate units)
48 fmsl (Seasonal High Water Table elevation)
3 inch (1.5 inch event for SA waters, I inch event for others)
10,694 c.f.
0.088 days
20.1 ft. x 263.5 ft. = 5,297 sq. ft. tho non dimensions)
16,548 c. f.
50 fmsl
51.40 frnsl
52 Fmsl
Form SWU-103 Rev 3.99 Page 1 of 3

W
,III. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C.
Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 2 1-1.1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants initials
AM& a. System is located 50 feet from class SA waters and 30 feet from other surface waters.
b. System is located at least 100 feet from water supply wells.
,i c. Bottom of system is at least 2 feet above the seasonal high water table.
d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
/ e. System is not sited on or in fill material or DWQ approval has been obtained.
F. System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way.
g. Drainage area for the device is less than 5 acres.
h. Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
i. System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for
areas draining to SA waters ). Design volume and infiltration calculations attached.
System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage. Calculations attached.
k. All side slopes stabilized with vegetated cover are no steeper than 3:1 (I -IN).
1. A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment
trap is provided.
m. Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or
dense vegetative cover is provided.
n. Vegetated filter is provided for overflow and detail is shown on plans (Required minimum
length is 50 feet for SA waters, 30 feet for other waters).
o. o. Flow distribution mechanism within the basin is provided.
p. A benchmark is provided to determine the sediment accumulation in the pretreatment device.
q. Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
r. System is designed to draw down the design storage volume to the proposed bottom elevation
under seasonal high water conditions within five days. A soils report and all pertinent draw -
down calculations are attached.
s. Plans ensure that the installed system will meet design specifications (constructed or restored)
(/ upon initial operation once the project is complete and the entire drainage area is stabilized.
Form 5WU-103 Rev 3.99 Page 2 of 3

,1N'. INFILTRATION BASIN OPERATION AND MAINTENANCE AGREEMENT
1. After every runoff producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without over -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the design depth reads 51.05 feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the infiltration basin.
5. If the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design function, other stonmwater control devices
as allowed by NCAC 21-1 .1000 must be designed, approved and constructed.
I acknowledge and agree by my signature below that I am responsible for the performance of the five
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 party.
Print Name and Title: Mark Ragozzino, Managing Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone] Date: ?�tsjUb
Signature:
Note: The legally responsible party should not he a homeowners association unless more than 50% of the lots
have been sold (Ind
%/a�resident of the subdivision has been named the president.t.� j
I, 1 rzk-, N a Notary Public for the State of Nor4,CA Olwex,county of
NIF(A) 00Ver , do herebycertifythat ( r K _ Z,Z.I I,iU personally appeared before me this
day of I " " b(U , and acknowledge the due execution of the forgoing infiltration basin maintenance
requirem % Hess m ind official seal,
�oTARr _ TQ
SP_r& _ My commission expires 0 3) I4 1 V 1
's Z '°U BLOC''
Form 8WU-1h1l,G`Page 3 of 3

Permit No. 56U'9D[pU S 1(
(to be provided by, D1110
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
ST0RMWA'f13R MANAGEMENT PERMIT APPLICATION FORM
INFILTRATION BASIN SUPPLEMENT
This form may be photocopied for use as an original
DWQ Stormwater Mana )ement flan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications showing
all stormwater conveyances and system details.
1. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE Phone Number: 910 343-1048
This workshect applies to: Basin No. 3 in Drainage Area 3
(as identified on plans) 01•om Form SWU-101)
IL DESIGN INFOIZ IATION — Attach supporting calculations / documentation. The soils report must be based upon an
actual field investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean seat level (fms]).
Soils Report Summary
Soil Type
Infiltration Ratc
SH W"I' Elevation
I3asin Design Parameters
Design Storm
Desigm Volume
Drawdown "Time
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
Top Elevation
Baymeade
23 in/h or eflhrlsf (circle appropriate toots)
48 fmsl (Seasonal High Water Table elevation)
3 inch (1.5 inch event for SA waters, I inch even! for others)
1,448 c.f.
0.104 days
16.2 ft. x 37.3 ft. = 604 sq. ft. (bottom dimensions)
2,521 c.f.
51 fins[
52.33 fmsl
53 l:msl
Form SWU-103 Rev 3.99 Page 1 of 3

Ill. REQUIRED ITEMS CHECKLIST
-'The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C.
Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 21-1 .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
System is located 50 feet from SA 30 feet from
a.
class waters and other surface waters.
+✓ b.
System is located at least 100 feet from water supply wells.
c.
Bottom of system is at least 2 feet above the seasonal high water table.
d.
Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
C.
System is not sited on or in fill material or DWQ approval has been obtained.
f.
System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right -of --way.
fY..,o g.
Drainage area for the device is less than 5 acres.
h.
Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
i.
System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for
areas draining to SA waters ). Design volume and infiltration calculations attached.
J.
System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage. Calculations attached.
k.
All side slopes stabilized with vegetated cover are no steeper than 3:1 (H:V).
1.
A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment
trap is provided.
in.
Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or
dense vegetative cover is provided.
n.
Vegetated filter is provided for overflow and detail is shown on plans (Required minimum
length is 50 feet for SA 30 feet for
+
waters, other waters).
o.
o. Flow distribution mechanism within the basin is provided.
p.
A benchmark is provided to determine the sediment accumulation in the pretreatment device,
q.
Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
r.
System is designed to draw down the design storage volume to the proposed bottom elevation
under seasonal high water conditions within five days. A soils report and all pertinent draw -
down calculations are attached.
s. Plans ensure that the installed system will meet design specifications (constructed or restored)
upon initial operation once the project is complete and the entire drainage area is stabilized.
Form SWU-1 03 Rev 3.99 Page 2 of 3

IV. !;NFILTRATION BASIN OPERATION AND MAINTENANCE AGREEMENT
•11. After every runoff producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without over -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the design depth reads 52.00 feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the infiltration basin.
5. If the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design ftinction, other stormwater control devices
as allowed by NCAC 21-1 .1000 must be designed, approved and constructed.
I acknowledge and agree by my signature below that I. am responsible for the performance of the five
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 party.
Print Name and Title: Mark Ra-ozzino, Managing Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone]
Signature: ri'h--J
Date: V � yo O .
Note: The legally responsible party shoulcl not be a homeowners association unless more than 50% of the lots
have been sold and a resiclent of the subdivision has been named the president.
t , . ( N�
1, 1 , J� a Notary Public for the State of �jr �-p � I`�Gy.Caunty of L
do hereby certify that
qZf personally appeared before me this 5T
day of -f�D and acknowledge the due execution of the forgoing infiltration basin maintenance
10
requireni�SQ}i id aj nid official seal,
s y P LIiG My commission expires ©f 141 pq
Form SWU-103 Rev . 9 Page 3 of 3

Permit No. Sri ff0605 ( (
(io be provided by DPVQJ
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMEN'r PERMIT APPLICATION FORM
INFILTRATION BASIN SUPPLEMENT
This form may be photocopied for use as an original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications showing
all stormwater conveyances and system details.
1. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE
This worksheet applies to: Basin No.
(as identified on plans)
Phone Number: [phone]
in Drainage Area
4
(from Form SWU--101)
II. DESIGN INFORMATION — Attach supporting calculations / documentation. The soils report must be based upon an
actual field investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean seal level (fmsl).
Soils Report Summary
Soil Type
Infiltration Rate
SHWT Elevation
Basin Design Parameters
Design Storm
Design Volume
Drawdown Time
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
Top Elevation
Rnvrne,gHe
23 PR or cf/hr/sf (circle appropriate units)
48 fmsl (Seasonal High I'Vater Table elevation)
3 inch (1.5 inch event for SA ivaters, 1 inch event for others)
6,011 c.f.
0.088 days
37.1 ft. x 79.7 ft. = 2,955 sq. ft. (bottom dimensions)
8,578 c.f.
51 frnsl
52.48 fms]
53 Fmsl
Form SWU-103 Rev 3.99 Page 1 of 3

IHsREQUIRED ITEMS CHECKLIST.
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C. .
Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 21­1 .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
441- a.
System is located 50 feet from class SA waters and 30 feet from other surface waters.
04 b.
System is located at least 100 feet from water supply wells.
06 c.
Bottom of system is at least 2 feet above the seasonal high water table.
04 d.
Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
e.
System is not sited on or in fill material or DWQ approval has been obtained.
f.
System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way.
g.
Drainage area for the device is less than 5 acres.
A - h.
Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
i.
System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for
areas draining to SA waters ). Design volume and infiltration calculations attached.
j.
System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage. Calculations attached.
k.
All side slopes stabilized with vegetated cover are no steeper than 3:1 (H:V).
1.
A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment
trap is provided.
m.
Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or -
dense vegetative cover is provided.
n.
Vegetated filter is provided for overflow and detail is shown on plans (Required minimum
length is 50 feet for SA waters, 30 feet for other waters).
o.
o. Flow distribution mechanism within the basin is provided.
PC p. A benchmark is provided to determine the sediment accumulation in the pretreatment device.
146 q. Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
r. System is designed to draw down the design storage volume to the proposed bottom elevation
under seasonal high water conditions within five days. A soils report and all pertinent draw -
down calculations are attached_
s. Plans ensure that the installed system will meet design specifications (constructed or restored)
upon initial operation once the project is complete and the entire drainage area is stabilized.
Form SWU-103 Rev 3.99 Page 2 of 3

IV. -,INFILTRATION BASIN OPERATION AND MAINTENANCE AGREEMENT
After every runoff producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without over -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the design depth reads 52.78 feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the infiltration basin.
5. If the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design function, other stormwater control devices
as allowed by NCAC 2H .1000 must be designed, approved and constructed.
I acknowledge and agree by my signature below that I am responsible for the performance of the five
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 party.
Print Name and Title: _ T Mark Ragozzino, Managing Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone] Date: 3U(tk
Signature:
Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots
have been sold and a resident of the subdivision has been named the president.
a�Nlotary Public for the State of G )49 k �xir 1�- rlCounty of j a w 1 r
DV Ilu+111fst'40 fie reby certify that fir L 7_2I k3h personally appeared before me this
clay of R and acknowledge the due execution of the forgoing infiltration basin maintenance
requirengnt _`tIORTA$W, d'a0 official seal,
p�aG My commission expires
NOVF-9-
"Paol1151111
Form SWU-103 Rev 3.99 Page 3 of 3

4
Permit No. S(U 5OC 056(
(to be provided by DIVQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
INFILTRATION BASIN SUPPLEMENT
This fornr may be photocopied for use as an original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement For each system, design calculations, soils report and plans and specifications showing
all stormwater conveyances and system details.
1. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PEPhone Number: [phone]
This worksheet applies to: Basin No. 5 in Drainage Area 5
(as identified on plans) (from Form SWU-101)
11. DESIGN INFORMATION -- Attach supporting calculations / documentation. The soils report must be based upon an
actual field investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean sea] level (fmsl).
Soils Report Summary
Soi i Type
Infiltration Rate
SHWT Elevation
Basin Design Parameters
Design Storm
Design Volume
Drawdown Time
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
`Cop Elevation
Bavmeade
23 in/ or cf/hr/sf (circle appropriate units)
48 fmsl (Seasonal High Water Table elevation)
3 inch (1.5 inch event for SA waters, 1 inch event for others)
3,104 c.f.
0.131 days
32 ft. x 32.3 ft. = 1,034 sq. ft. (bonoin dimensions)
3,671 c.f.
51 fmsl
52.75 fmsl
53 Fmsl
Form SWU-103 Rev 3.99 Page 1 of 3

Ill. REQUIRED ITENIS CFIECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C.
Department ofEnvironment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 21-I .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
a. System is located 50 feet from class SA waters and 30 feet from other surface waters.
YKb. System is located at least 100 feet from water supply wells.
(14 c. Bottom of system is at least 2 feet above the seasonal high water table.
d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
e. System is not sited on or in fill material or DWQ approval has been obtained.
f. System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way.
g. Drainage area for the device is less than 5 acres.
h. Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
I. System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for
r areas draining to SA waters ). Design volume and infiltration calculations attached.
j. System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage. Calculations attached.
k. All side slopes stabilized with vegetated cover are no steeper than 3.:1 (I-I:V).
1. A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment
trap is provided.
m. Bottom of the device is covered with a layer of clean sand to an average depth oF4 inches or
dense vegetative cover is provided.
n. Vegetated filter is provided for overflow and detail is shown on plans (Required minimum
length is 50 feet for SA waters, 30 feet for other waters).
o. o. Plow distribution mechanism within the basin is provided.
p. A benchmark is provided to determine the sediment accumulation in the pretreatment device.
q. Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
r. System is designed to draw down the design storage volume to the proposed bottom elevation
under seasonal high water conditions within five days. A soils report and all pertinent draw -
down calculations are attached.
s. Plans ensure that the installed system will meet design specifications (constricted or restored)
upon initial operation once the project is complete and the entire drainage area is stabilized.
Form SWU-103 Rev 3.99 Page 2 of 3

r W. INFILTRATION BASIN OPERATION AND MAINTENANCE AGREEMENT
1. After every runo IT producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without over -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the design depth reads 52.31 feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the infiltration basin.
5. If the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design function, other stormwater control devices
as allowed by NCAC 2I-1 .1000 must be designed, approved and constructed.
I acknowledge and agree by my signature below that I am responsible for the performance of the five
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 party.
Print Name and Title: Mark Ragozzino, Managing Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone] Date: g � U10 (�'
Signature:
Note: The legally resp6isible party should not be a homeowners association unless more than 50% of the lots
have been sold` and a resident of the subdivision has been named (he president. h
I,_�k 1 1<SO f) , a Notary Public for the State of ! V0_4k(ILI- 'I (kiG , County of lit e( U
Q 0Do do hereby certify that Ma r—L 930P 2?'l OJ0 personally appeared before me this
day of _ 4/ and acknowledge the clue execution of the forgoing infiltration basin maintenance
require r en rle�s�ly to?end official seal,
Y
y A My commission expires
3�
Form SWU-103`9 Page 3 of 3

t Permit No. SGu 9 0 WS l
(to be provided by DPVQ
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
INFILTRATION BASIN SUPPLEMENT
This form nray be photocopied for rue as an original
DWQ Stormwater Management -Plan-Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications showing
all stonnwater conveyances and system details.
I. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE _ Phone Number: _ [phone]
This wodcsheet applies to: Basin No. 6 in Drainage Area 6
(as identified oir plaits) {from Form SWU-101)
II. DESIGN INFORMATION — Attach supporting calculations / documentation. The soils report must be based upon an
actual field investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean seal level (fmsl).
Soils Report Summary
Soil Type
Infiltration Rate
SHWT Elevation
Basin Design Parameters
Design Storm
Design Volume
Drawdown Time
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
Top Elevation
Ravmeade
23 in/h or cf/hr/sf (circle appropriate units)
48 fmsl (Seasonal High Water Table elevation)
3 inch (1.5 inch event for SA waters, 1 inch event for others)
4,672 c. f.
0.067 days
22.9 ft. x 133 ft. = 3,046 sq. ft. (bottom dimensions)
8.040 c. f.
50 fmsl
51.15 fmsl
52 Fmsl
Form SWU-103 Rev 3.99 Pagel of 3

W.'REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C.
Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 21-1 .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
a. System is located 50 feet from class SA waters and 30 feet from other surface waters.
040 b. System is located at least 100 feet from water supply wells.
/ c. Bottom of system is at least 2 feet above the seasonal high water table.
i� _ d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
C. System is not sited on or in bill material or DWQ approval has been obtained.
£ System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access casements to the nearest public right-of-way.
g. Drainage area for the device is less than 5 acres.
h. Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
i. System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for
areas draining to SA waters ). Design volume and infiltration calculations attached.
J. System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage. Calculations attached.
u/ k. All side slopes stabilized with vegetated cover are no steeper than 3:1 (H:V).
1. A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment
trap is provided.
m. Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or
(16 n
AM 0
p
q
dense vegetative cover is provided.
Vegetated filter is provided for overflow and detail is shown on plans (Required minimum
length is 50 feet for SA waters, 30 feet for other waters).
o. Flow distribution mechanism within the basin is provided.
A benchmark is provided to determine the sediment accumulation in the pretreatment device.
Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
System is designed to draw down the design storage volume to the proposed bottom elevation
under seasonal high water conditions within five days. A soils report and all pertinent draw -
down calculations are attached.
♦ s. Plans ensure that the installed system will meet design specifications (constructed or restored)
A(/ upon initial operation once the project is complete and the entire drainage area is stabilized.
Form SWU-103 Rev 3.99 Page 2 of 3

I)'ANFILTRATION BASIN OPERATION AND MAINTENANCE AGREEMENT
After every runoff producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without aver -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the design depth reads 50.86 feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the infiltration basin.
5. If the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design function, other stormwater control devices
as allowed by NCAC 214 .1000 must be designed, approved and constructed.
I acknowledge and agree by my signature below that I am responsible for the performance of the five
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 party.
Print Name and Title: Mark Ragozzino, Managing Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone] Date:
Signature:
Nate: The legally responMle party should not be a homeowners association unless more than 50% of the lots
have been sold and a resident of the subdivision has been named the president. r
e, (It Soi� a Notary Public for the State of lyp ��p�t �� , County of NPw
0NSA Ue.tr , do hereby certify that personally appeared before me this
�tlHl tlrpr/
day of � ' r','4r V& , and acknowledge the due execution of the forgoing infiltration basin maintenance
1-1w u
requircriA l i�� i J and official seal,
f
My commission expires
- U13
1� 10
Form SW U,1;a99��` Page 3 of 3

Permit No. 6(A-) ly OCoUU 50
(to be provided by DPJ"Q)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
INFILTRATION BASIN SUPPLEMENT
This fornr may be photocopied for use as on orignzal
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications showing
all stormwater conveyances and system details.
I. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE Phone Number: [phone]
This workslieet applies to: Basin No. 7 in Drainage Area 7
(as identified on plans) (fonr Form SWU401)
It. DESIGN INFORMATION — Attach supporting calculations / documentation. The soils report must be based upon an
actual field investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean seal level (fmsl).
Soils Report Summary
Soil Type
Infiltration Rate
S14WT Elevation
Basin Design Parameters
Design Storm
Design Volume
Drawdown Time
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
Top Elevation
Mandarin /
Baymeade
23 EEd or cf/hr/sf (circle appropriate units)
48 fmsl (Seasonal High Water Table elevation)
3 inch (1.5 inch event for SA walers, I inch event far others)
2,668 c.f.
0.17 days
4.1 ft. x 166 ft. = 688 sq. ft. (bottom rlirnensions)
5,011 c.f,
52 fmsl
53.32 fms]
54 Fmsl
Form SWU-103 Rev 3.99 Page I of 3

;III_ REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C.
Department of Environment, FIealth and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 2H .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
a. System is located 50 feet from class SA waters and 30 feet from other surface waters.
b. System is located at least 100 feet from water supply wells.
c. Bottom of system is at least 2 feet above the seasonal high water table.
d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
e. System is not sited on or in fill material or DWQ approval has been obtained.
f. System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access casements to the nearest public right-of-way.
g. Drainage area for the device is less than 5 acres.
It. Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
i. System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for
areas draining to SA waters ). Design volume and infiltration calculations attached.
j. System is sized to take into account the runoffat the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage. Calculations attached.
k. All side slopes stabilized with vegetated cover are no steeper than 3:1 (H:V).
.94 1. A pretreatment device such as a catch basin, grease trap, filter strip, grassed Swale or sediment
trap is provided.
m. Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or
dense vegetative cover is provided.
n. Vegetated filter is provided for overflow and detail is shown on plans (Required minimum
length is 50 feet for SA waters, 30 feet for other waters).
o. o. Flow distribution mechanism within the basin is provided.
p. A benchmark is provided to determine the sediment accumulation in the pretreatment device.
Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
System is designed to draw down the design storage volume to the proposed bottom elevation
under seasonal high water conditions within five days. A soils report and all pertinent draw -
down calculations are attached.
s. Plans ensure that the installed system will meet design specifications (constructed or restored)
upon initial operation once the project is complete and the entire drainage area is stabilized.
Form SWU-103 Rev 3.99 Page 2 of 3

"IV. INFILTRAT[ON BASIN OPERATION AND MAINTENANCE AGREEMENT
Y. After every runoff producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure. to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without over -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the design depth reads 52.99 feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the infiltration basin.
5. If the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design function, other stormwater control devices
as allowed by NCAC 21-1 A000 must be designed, approved and constructed.
[ acknowledge and agree by my signature below that I am responsible for the performance of the five
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 party.
Print Name and Title: _ Mark Ragozzino,_Managing Member
Address: The Commons at Calabash LLC 234 Sea Gull Lane Wilmin ton NC 28409
Phone: [phone] Date:] O b
Signature:
Note: The legally respo4ki5 e party should not be a homeowners association unless more than 50% of the lots
have been sold and a resident of the subdivision has been named the president.i
1, � e— (-74A1 &jrJ, a Notary Public for the State of Nbr4k art,1
3 Lkx, County of 1Veo
III avec =_ do hereby certify that Mat Zzll D personally appeared before me this
day of f=�'-ILlL' ^t- 27 ,and acknowledge the due execution of the forgoing infiltration basin maintenance
requiremcZ?i1t@� fitness my ltynd official seal,
-fR`
a ���r _yes
My commission expires l vl
PUB Cj
Farm 5WU 1�Nli,�``�� Page 3 of 3
)Si�k

Permit No. SLv 5 UCvU51(
(to be provided by UWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
.INFILTRATION BASIN SUPPLEMENT
This form may be photocopied for use as an original
DW , Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications showing
all stormwatcr conveyances and system details.
I. PROJECT INFOI;LMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE
This worksheet applies to: Basin No. 8
(as identified on plans)
Phone Number: [phone]
in Drainage Area
0
(front Form SWU-101)
II. DESIGN INFORMATION — Attach supporting calculations / documentation. The soils report must be based upon an
actual field investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean seal level (Fmsl).
Soils Report Summary
Soil Type
Infiltration Rate
SFIWT Elevation
Basin Design Parameters
Design Storm
Design Volume
Drawdown Time
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
Top Elevation
Mandarin /
RAVMf-q CjP
23 in/h or cflhrlsf (circle appropriate units)
48 fmsl (Seasonal High Water Table elevation)
3 inch (1.5 inch event far SA waters, I inch event for others)
4,323 c.f.
0.24 days
4 ft. x 197 ft. = 792 sq. ft. (bottom dimensions)
5,854 c. F.
52 fmsl
53.62 fmsl
54 hmsl
Form SWU-103 Rev 3.99 Page 1 of 3

_r
v
.Ili. REQUIRED ITEms CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C.
Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 21-I .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
116
System is located 50 feet from class SA waters and 30 feet from other surface waters.
b. System is located at least 100 feet from water supply wells.
Bottom of system is at least 2 feet above the seasonal high water table.
d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
System is not sited on or in fill material or DWQ approval has been obtained.
System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way.
Drainage area for the device is less than 5 acres.
Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for
areas draining to SA waters ). Design volume and infiltration calculations attached.
System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage. Calculations attached.
46 k. All side slopes stabilized with vegetated cover are no steeper than 3:1 (H:V).
1. A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment
16 trap is provided.
r� m. Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or
dense vegetative cover is provided.
n. Vegetated Filter is provided for overflow and detail is shown on plans (Required minimum
length is 50 feet for SA waters, 30 feet for other waters).
o. o. Flow distribution mechanism within the basin is provided.
p. A benchmark is provided to determine the sediment accumulation in the pretreatment device.
q. Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
r. System is designed to draw down the design storage volume to the proposed bottom elevation
under seasonal high water conditions within five days. A soils report and all pertinent draw -
down calculations are attached.
Ael
s. Plans ensure that the installed system will meet design specifications (constructed or restored)
upon initial operation once the project is complete and the entire drainage area is stabilized.
Form SWU-103 Rev 3.99 Page 2 of 3

IV. INFILTRATION BASIN OPERATION AND MAINTENANCE AGREEMENT
After every runoff producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without over -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shalt not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the design depth reads 53.22 feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the infiltration basin.
5. If the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design function, other stormwater control devices
as allowed by NCAC 21-1 .1000 must be designed, approved and constructed.
I acknowledge and agree by my signature below that I am responsible for the performance of the five
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 party.
Print Name and Title: Mark Ragozzino, Managing Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone] Date: eus_-1 bb
Signature:
Note: The legally responsYble party should not be a homeowners association unless more than 50% of the lots
have been sold and a resident of the subdivision has been named the president.
I �e. t =}� - , __-, a Notary Public for the State of IVDI'�F-h ,6�C t�ounty of We Uj
Qt0g g IOC do hereby certify thaty r _. l k� ZZ�A}p personally appeared before me this
day of AUL6+ ,,, L�b�o and acknowledge the due execution of the forgoing infiltration basin maintenance
requireme� � � 0;pjid official sea],
` O
aor�A�
My commission expires
Form SWU 1 G�+`'Page 3 of 3
ffffflfflFl llll/j1��`

Permit No. d (J�lstr
(to be provided by D K'Q)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
INFILTRATION BASIN SUPPLEMENT
This form may be photocopied for use as an original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications showing
all stormwater conveyances and system details.
I. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE
This worksheet applies to: Basin No. 9B
(as identified on plans)
Phone Number: T [phone]
in Drainage Area
9B
(froth Form SWU-101)
II. DESIGN INFORMATION — Attach supporting calculations / documentation. The soils report must be based upon an
actual held investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean seal level (fms]).
Soils Report Summary
Soil Type
Infiltration Rate
SHWT Elevation
Basin Design Parameters
Design Storm
Design Volume
Drawdown "rime
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
Top Elevation
Baymeade
I Leon
23 in/tior cf/hr/sf (circle appropriate units)
48 fmsl (Seasonal High Water Table elevation)
3 inch (1.5 inch event for SA waters, 1 inch event for others)
7,792 c.f.
0.14 days
20.73 ft. x 117 ft. = 2,425 sq. ft. (botionr dimensions)
14.155 c.f.
50 fmsl
51.99 fnlsl
53 Fmsl
Form SWU-103 Rev 3.99 Page 1 of 3

III. WCQUIRED ITEMS CIIECKIAST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C.
Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 214 .1005.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
116 a. System is located 50 feet from class SA waters and 30 feet from other surface waters.
b. System is located at least 100 feet from water supply wells.
c. Bottom of system is at least 2 feet above the seasonal high water table.
d. Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
e. System is not sited on or in fill material or DWQ approval has been obtained.
f. System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way.
g. Drainage area for the device is less than 5 acres.
h. Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
i. System captures and infiltrates the runoff from the first 1.0 inch of rainfall (1.5 inch event for
areas draining to SA waters ). Design volume and infiltration calculations attached.
j. System is sized to take into account the runoff at the ultimate built -out potential from all
surfaces draining to the system, including any off -site drainage. Calculations attached.
k. All side slopes stabilized with vegetated cover are no steeper than 3:1 (H:V).
1. A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment
trap is provided.
m. Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or
dense vegetative cover is provided.
n. Vegetated filter is provided for overflow and detail is shown on plans (Required minimum
�W length is 50 feet for SA waters, 30 feet for other waters).
o. o. Flow distribution mechanism within the basin is provided.
p. A benchmark is provided to determine the sediment accumulation in the pretreatment device.
Nq. Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
r. System is designed to draw down the design storage volume to the proposed bottom elevation
1�/ under seasonal high water conditions within five days. A soils report and all pertinent draw-
-calculations are attached.
s. Plans ensure that the installed system will meet design specifications (constructed or restored)
upon initial operation once the project is complete and the entire drainage area is stabilized.
Form SWU-103 Rev 3.99 Page 2 of 3

IV. 10ILTRA'TION 13ASIN OPERATION AND MAINTE NANCE AGREEMENT
.1
1. After every runoff'producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without over -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the design depth reads 51.49 feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the infiltration basin.
5. if the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design function, other stormwater control devices
as allowed by NCAC 2H .1000 must be designed, approved and constructed.
I acknowledge and agree by my signature below that I am responsible for the performance of the five
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 party.
Print Name and. Title: Mark Ra ozzino Managing_Member
Address: The Commons at Calabash LLC, 234 Sea Gull Lane, Wilmington, NC 28409
Phone: [phone] Date: i>
Signature:
Note: The legally responsible party should not be a homeowners association unless niore than 50% of the lots
Have been sold and a resident of the subdivision has been named the president.
1, ` �l L el (_ eklt So fV , a Notary Public for the State of94 Ui1r,0, fN X , County of �A o
I` nW VVP_t- do hereby certify that _Nyt ,—L Zzt ND personally appeared before me this JE 4—
day ofu�[j,DD D (o , and acknowledge the due execution of the forgoing infiltration basin maintenance
requireme�t{S.��t .4y�i'ftd and official seal,
a, z6- '.
[MIA IEAir
Form SW 13e� 0�1
O Y e 5`t\
t101i1111ij11R
My commission expires
Page 3 of 3
D3{ 1`t}Pei

Permit No. � Bo(xsj(
(to be provided by DWo
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
INFILTRATION BASIN SUPPLEMENT
This form may be photocopied for use as an original
DWO Storm_water Management Plan Review:
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications showing
all stormwater conveyances and system details.
I. PROJECT INFORMATION
Project Name: The Commons at Calabash
Contact Person: Richard M. Collier, PE
This worksheet applies to: Basin No.
(as identified on plans)
Phone Number: __(910)343-1048__
in Drainage Area 10
(from Form SWU-101)
II. DESIGN INFORMATION -- Attach supporting calculations I documentation. The soils report must be based upon an
actual field investigation and soil borings. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean seal level (fmsl).
Soils Report Summary
Soil Type
Infiltration Rate
SHWT Elevation
Basin Design Parameters
Design Storm
Design Volume
Drawdown Time
Basin Dimensions
Basin Size
Basin Volume Provided
Basin Elevations
Bottom Elevation
Storage Elevation
Top Elevation
Form SWU-103 Rev 3.99
Mandarin /
Leon
23 0 or eM r/sf (circle appropriate units)
48 frnsl (Seasonal High Water Table elevation)
3
inch (L5 inch event for SA waters, 1 inch event for others)
6,719
c.f.
0.15
days
42.5
ft. x 45.6
ft. = 1,938 sq. ft. (bottom dimensions)
6,822
c.f.
50
fmsl
RECEIVED
51.98
fms]
NOV 0 6 2006
52
Fmsl
DWQ
PROJ #
Page 1 of 3

J 111. REQUIRED ITEIINIS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual (N.C.
Department of Environment, Health and Natural Resources, February 1999) and Administrative Code Section: 15 A
NCAC 21-1 .1008.
Initial in the space provided to indicate that the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. Attach justification if a requirement has not been met.
Applicants Initials
a.
b.
C.
d.
C.
lie
System is located 50 feet from class SA waters and 30 feet from other surface waters.
System is located at least 100 feet from water supply wells.
Bottom of system is at least 2 feet above the seasonal high water table.
Bottom of the system is 3 feet above any bedrock or impervious soil horizon.
System is not sited on or in fill material or DWQ approval has been obtained.
System is located in a recorded drainage easement for the purposes of operation and
maintenance and has recorded access easements to the nearest public right-of-way.
g. Drainage area for the device is less than 5 acres.
h. Soils have a minimum hydraulic conductivity of 0.52 inches per hour and soils report is
attached.
i. System captures and infiltrates the runoff from the First 1.0 inch of rainfall (1.5 inch event for
areas draining to SA waters ). Design volume and infiltration calculations attached.
j. System is sized to take into account the runoff at the ultimate built -out potential from all
Surfaces draining to the system, including any off -site drainage. Calculations attached.
k. All side slopes stabilized with vegetated cover are no steeper than 3:1 (I-I:V).
1. A pretreatment device such as a catch basin, grease trap, filter strip, grassed swale or sediment
trap is provided.
m. Bottom of the device is covered with a layer of clean sand to an average depth of 4 inches or
dense vegetative cover is provided.
n. Vegetated filter is provided for overflow and detail is shown on plans (Required minimum
length is 50 feet for SA waters, 30 feet for other waters).
o. o. Flow distribution mechanism within the basin is provided.
p. A benchmark is provided to determine the sediment accumulation in the pretreatment device.
q. Runoff in excess of the design volume bypasses off-line systems (bypass detail provided).
r. System is designed to draw down the design storage volume to the proposed bottom elevation
under seasonal high water conditions within five days. A soils report and all pertinent draw -
down calculations are attached.
s. Plans ensure that the installed system will meet design specifications (constructed or restored)
)46 upon initial operation once the project is complete and the entire drainage area is stabilized.
Form SWU-103 Rev 3.99 Page 2 of 3

f-_
,),IV. INFILTRATION BASIN OPERATION AND MAINTENANCE AGREEMENT
1. After every runoff producing rainfall event and at least monthly inspect the infiltration system for erosion, trash
accumulation, vegetative cover, and general condition.
2. Repair eroded areas immediately, re -seed as necessary to maintain adequate vegetative cover, mow vegetated
cover to maintain a maximum height of six inches, and remove trash as needed.
After every runoff producing rainfall event and at least monthly inspect the bypass, inflow and overflow
structures for blockage and deterioration. Remove any blockage and repair the structure to approved design
specifications.
4. Remove accumulated sediment from the pretreatment system and infiltration basin annually or when depth in the
pretreatment unit is reduced to 75% of the original design depth. The system shall be restored to the original
design depth without over -excavating. Over -excavating may cause the required water table separation to be
reduced and may compromise the ability of the system to perform as designed. Removed sediment shall be
disposed of in an appropriate manner and shall not be handled in a manner that will adversely impact water
quality (i.e. stockpiling near a stormwater treatment device or stream, etc.).
A benchmark shall be established in the pretreatment unit. The benchmark will document the original design
depth so that accurate sediment accumulation readings can be taken. The measuring device used to determine the
depth at the benchmark shall be such that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
�c
When the design depth reads feet in the pretreatment unit, the sediment shall be removed from both
the pretreatment unit and the inf;ltratian basin.
5. If the Division determines that the system is failing, the system will immediately be repaired to original design
specifications. If the system cannot be repaired to perform its design function, other stormwater control devices
as allowed by NCAC 211 .1000 must be designed, approved and constructed.
I acknowledge and agree by my signature below that I am responsible for the performance of the five
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 party.
Print Name and Title: Mark Ragozzino, Managing Member
Address:
The Commons at Calabash LLC
234 Sea Gull Lane Wilmington,
NC 28409
Phone:
910-392-5793
Date:
F I I:d o ko
Signature: ' Yv�w
Note: The legally responsible" party should not be a homeowners association unless more than 50% of the lots
have been sold and a resiclent of the subdivision has been named the president.
I, i ed, t a ma
Public for the State of N1 p I -IL O.1`pl � � � County of >fl vj
Q WP U a° (r , do hereby certify that I' VAR C' i� QQZ--Zj hjO personally appeared before me this
day of , and acknowledge the due execution of the forgoing infiltration basin maintenance
requiremleltfbtOnYmyynd official seal,,
SCt\l My commission expires
Form SW U-1t % 9,110 Page 3 of 3

INFILTRATION TRENCH ANALYSIS
Filename:
S:1WQSlSTORMWATERIEXCELSPREADSHEETSIINTRENCH1060511.nov06
Initial Run Date: July 17, 2006
Project # SW8
060511.nov06
Date
06-Nov-06
Project Name
The Commons at Calabash
Reviewer
L. Lewis
Receiving Stream
Calabash River
Classification SA
Drainage Basin
LBR59
Index #
15-25-5
Site Area
15.79 acres
Impervious Area Calculation
Trench 1 Trench 2
Trench 3A
Trench 9
Trench 9A
Buildings, sf=
7561
8029
10776
23579
23678
Parking/Street, sf=
41487
74458
15929
6913
Concrete, sf =
1481
.1683
1027
Future, sf =
Other, sf =
Total SUA
50529
84170
27732
30492
23678
0
Drainage Area
52272
87556
27732
30492
23678
% Impervious=
96.7%
96.1 %
100.0%
100.0%
100.0%
#DIV/0!
Cc=
0.931
0.926
0.962
0.973
0.980
#DIV/01
Design Storm, in.: 3 3
3
3
3
Rv 0.92 0.92
0.95
0.95
0.95
#DIV/0!
Req. Volume, cf : :-12022 20033
6586. , , ....'
..::7:242 ......
':.....''5624......
Pipe 1 Diameter, ft= 3 3
3.5
3
3
Pipe 1 Run Length,ft 240 275
195
130
70
No. of Pipe 1 Runs 6 7
1
4
6
Pipe 1 Area,'sf = 42 49
10
28
42
0
Storage in Pipe 1,cf 10179 13607
1876
3676
2969
0
Length Of Trench,ft 240 275
195
130
70
Width Of Trench,ft 36 42
23.5
28
42
Height Of Trench.ft 3.5 3.5
4.13
3.5
3.5
Voids Volume, cf 8024 10727
6820
3626
2928
1 0
Volume Provided
Bottom Elevation 50 50
50
50
50
SHWT Elevation 48 48
48 .
48
48
Overflow Elevation 53.5 53.5
54.13
53.5
53.5
Infiltration Rate,inlhr 13 13
13
13
13
SA @Bottom , sf 8640 11550
4582.5
3640
2940
0
Drawdown Time ...:..1:28 .... ;1 60
;1.33
184......
.:.....17:7 :....>
.....4DIVI4!
25 YEAR 24 HOUR STORM
Qr= C i A = 0.37 0.61
0.20
0.22
0.18 #DIV/0!
Qp, bottom of basin= 2.60 3.48
I
1.38
1.10
0.88 0.00
I
10 YEAR 10 MIN HIGH INTENSITY EVENT
i = 7 inches 1
hour
Volume = 4692.23 1 7814.63
I 2571.36
I 2861.20
2237.34 I #DIV/01