HomeMy WebLinkAboutCENTERPOINT PLAZA (RE-APPLICATION) - PDP - PDP150014 - REPORTS - EROSION CONTROL LETTER/REPORT (3)1
EROSIONCONTROLREPORT FOR
CENTERPOINT PLAZA FIRST REPLAT
Job Number 1028
September 30, 2015
2
EROSION CONTROL REPORT
FOR
CENTERPOINT PLAZA
PREPARED FOR:
NEXGEN PROPERTIES, LLC
One Denver Tech Center
5251 DTC Parkway, Suite 8000
Greenwood Village, CO 80111
(303) 923-2442
PREPARED BY:
RICK ENGINEERING COMPANY, INC.
4 Inverness Court East #300
Englewood, CO 80112
(303) 565-8080
JN 1028
September 30, 2015
3
Table of Contents
1.0 Introduction
1.1 Site Description………………………………………………………………………5
1.2 Stormwater Management Controls: …………………………………………………6
1.3Vehicle Tracking Control……………………………………………………………6
1.4 Location of Contaminated Soils ……………………………………………………6
1.5 Vehicular Traffic……………………………………………………………………6
1.6 Location of Material Stockpile……………………………………………………..6
1.7 Batching Plant………………………………………………………………………6
1.8 Dewatering………………………………………………………......………………7
1.9 Soil Characteristics………………………………………………….………………7
1.10 Seeding and Mulching……………………………………………………………7
2.0 Construction Sequence………………………………………………………………………8
2.1 Erosion Control Plan…………………………………………………………………….…10
2.2 Erosion Control Security Calculations…………………………………………….…….…11
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List of Figures
Figure, 1 Project Site Location…………………………………………………………………1
List of Tables:
Table 1 Construction Sequence……………………………………………………………………
Table 2 Estimate of Probable Cost for Erosion Control Escrow Security………………………
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1.0 Introduction
1.1 Site Description
Centerpoint Plaza (project site) is located in the northwest quarter of Section 20,
Township 7 North, Range 68 West of the 6th
Principal Meridian in the City of
Fort Collins, Colorado. More specifically, the project site is bounded by
Timberline Road on the west, Midpoint Drive on the north, Railroad Right of
Way on the north and industrial development to the east as shown on the location
map (Figure 1) below.
The project site is a total of approximately 2.34 acres. Phase 1 development was
completed in May of 2006. The Phase 2 area is approximately 1.57 acres. Soil is in
undisturbed state on the site and consists of native weeds and grasses. There are no
impervious areas on the site other than a walkway running North South. The project is
going to be a 2.5 story commercial building with other site infrastructure consisting of
paved parking areas with curb, gutter and sidewalk, utility service line and storm utilities.
The site is not near any major waterbody and not within any regulatory floodplains
Figure 1: Project Location
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designated by the City of Fort Collins or FEMA.
Silt fence will be installed before any site disturbance to check erosion. After the site is
graded, it will be protected using Wattles laid on contours and the site will be hydroseeded
to prevent any erosion post grading. Inlets shall be protected using Rock socks and wattles.
Silt fences will be removed after the site has stabilized and there is required amount of
vegetation. In addition to stormwater discharge there are no other sources of non
stormwater discharge through the site.
1.2 Stormwater Management Controls:
Description of all SWMC:
The project has no SWMP administrator as of now, a SWMP Administrator will be designated to
the project when the project will be awarded to a contractor. During the performance of the work
required by the plans, the contractor shall carry out proper measures wherever necessary to reduce
dust nuisance. The contractor will be held liable for any damage resulting from dust originating
from his operations under these plans, on right-of-way or elsewhere.
1.3 Vehicle Tracking Control:
Wherever construction vehicles access routes intersect paved roads, provisions shall be made to
minimize the transport of sediments by runoff or vehicles tracking on the paved surface. A
stabilized construction is required as per shown on the map. The contractor shall be responsible for
clearing tracked mud on a daily basis.
1.4 Location of Contaminated Soils
There are no contaminated soils located on the project site.
1.5 Vehicular Traffic
All the vehicular traffic on site will pass through North East side of the site and over the Vehicle
Tracking pad so that tracking of mud on streets can be minimized.
1.6 Location of Material Stockpile
Location of Water Material Stockpile (Should be minimum 50 feet away from any inlet structure
or watercourse). Please see attached plan
1.7 Batching Plant
There shall not be any asphalt or concrete batch plant on the site. Portable toilets shall be provided
by the contractor (Provide location, 50 feet away from any inlet or water source) Please see
attached plan
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1.8 Dewatering
It is anticipated that the project site will not involve groundwater and stormwater dewatering
practice and hence any scope of spills is minimal
1.9 Soil Characteristics
According to Natural Resources Conservation Services (NRCS) Hydrologic Soil Group of site is C
and the vegetation consists of native weed and grasses.
1.10 Seeding and Mulching
For evergreen trees, 6 feet diameter mulch shall be provided with a 6” planting rim for trees in
dryland planting beds and in irrigated native seeds areas where irrigation zones are to be shut down
after establishment.
For deciduous trees, 4” depth of mulch is suggested with a 6’ diameter mulch ring. Mulch has to be
kept away from woody trunk. For shrubs 4” mulch depth is suggested
2.0 Construction Sequence:
A construction timeline has not yet been completed due to the project being in the “entitlement:”
stage. A construction schedule and the below sequence will be completed.
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Table 1: Construction Sequence
Mobiliz
ation
Demoli
tion
Grad
ing
Utilities
Installati
on
Flat
work
Installa
tion
Vertica
l
Installa
tion
Landsc
ape
Demobili
zation
Best
Management
Practices
(BMPs)
Structural
“Installation”
Silt Fence
Barriers*
Contour
Furrows
(Ripping /
Disking)
Sediment Trap
/ Filter
Vehicle
Tracking Pad*
Flow Barriers
(Wattles)*
Inlet Filter
Bags*
Any
prior
inlets
that
could
use
protecti
ng
Rock Bags* Any
prior
inlets
that
could
use
protecti
ng
Terracing
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Stream Flow
Diversion*
Rip Rap
Collecting
Asphalt /
Concrete Saw
Cutting Waste
*All BMPs to
be Removed
once
Construction is
Complete.
Vegetative
Temporary
Seeding
Planting
Any
time
the site
will sit
dorman
t longer
than 30
Days.
Mulching/Seal
ant
Any
time
the site
will sit
dorman
t longer
than 30
Days.
Permanent
Seeding
Planting
Sod
Installation
Rolled
Products :
Netting/Blanke
ts/Mats
Any
time
the site
will sit
dorman
t longer
than 30
Days.
Other:
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2.1 Erosion Control Plan: Please see next page.
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2.2 Erosion Control Security Calculations:
Table 2 Estimate of Probable Cost for Erosion Control Escrow Security
Engineer’s Estimate of Probable Cost for Erosion Control Escrow Security
Project: Center Point Plaza First Replat
Project No: 1028
Calculations By: Rick Engineering Company Date:
Itemized Costs:
Item Unit Quantity Unit Cost Total
Silt Fence LF 880 $ 2.00 $ 1,760.00
Sandbags LF 35 $ 4.00 $ 140.00
Sed. Bas. EA 1 $ 1,600.00 $ 1,600.00
Subtotal $ 3,500.00
Multiplier 1.5
Total $ 5,250.00
Formula Based:
Unit Quantity Unit Cost Total
Revegetation AC 1.57 $ 775.00 $ 1,216.75
Multiplier 1.5
Total $ 1,825.13
Escrow Security (greater of two estimates, $ 3000.00 min.) $ 5,250.00