HomeMy WebLinkAboutCENTERPOINT PLAZA (RE-APPLICATION) - PDP - PDP150014 - REPORTS - EROSION CONTROL LETTER/REPORT1
EROSIONCONTROLREPORT FOR
CENTERPOINT PLAZA FIRST REPLAT
Job Number 1028
November 11, 2015
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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
November 11, 2015
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Table of Contents
1.0 Introduction
1.1 Site Description………………………………………………………………………5
1.2 Stormwater Management Controls: …………………………………………………6
1.3 Disturbed Soils ………... ……………………………………………………………6
1.4 Vehicle Tracking Control……………………………………………………………6
1.5 Location of Contaminated Soils ……………………………………………………6
1.6 Vehicular Traffic………………………………………………………….…………7
1.7 Location of Material Stockpile……………………………………………..………..7
1.8 Batching Plant………………………………………………………………….……7
1.9 Portable Toilets, Workers Trash and Onsite Waste Management Practices…,,,.…... 7
1.10 Dewatering………………………………………………………...,...…………..…7
1.11 Soil Characteristics………………………………………………….,……,,………7
1.12 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…………………………………………………………………5
List of Tables:
Table 1 Construction Sequence…………………………………………………………………8
Table 2 Estimate of Probable Cost for Erosion Control Escrow Security…………………… 11
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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
designated by the City of Fort Collins or FEMA.
Figure 1: Project Location
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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. 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. The SWMP Administrator shall be
responsible for all SWMP needs including immediate maintenance and correction of BMPs on site.
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 Disturbed and Stored Soils
Approximately 1.57 acres will be disturbed during construction and any disturbed soils shall be
stabilized with the appropriate BMPs on site as shown on the erosion control plan and sequencing
chart. Earthwork on site is anticipated to be a balance, and/or any excess shall be hauled off-site.
No large stock piles are anticipated and no stock pile shall exceed 10 feet in height. Minimal stock
piles of utility spoils may occur on site and shall be stabilized to prevent sediment transport by
surface roughing, watering and perimeter silt fencing.
1.4 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 Vehicle Tracking Control (VTC) pad shall be installed and maintained throughout
construction, as shown on the drainage and erosion control plan. The contractor shall be
responsible for clearing tracked mud on a daily basis.
1.5 Location of Contaminated Soils
There are no contaminated soils located on the project site.
1.6 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 is minimized. Contractors shall take advantage of
parking, loading and unloading on the existing paved areas to the north of the site, where available,
in order to minimize parking on the active construction site.
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1.7 Location of Material Stockpile
Location of Material Stockpiles shall be located a minimum 50 feet away from any inlet structure
or watercourse. Material stock piles such as utility piping, construction building materials are
anticipated to be located to the west of the site, in the proposed parking areas, south of the
proposed building. During construction, material stock piles shall be secured and covered during
any storm events.
1.8 Batch Plant
There shall not be any asphalt or concrete batch plants on the site.
1.9 Portable Toilets, Workers Trash and Onsite Waste Management Practices
Portable toilets shall be provided by the contractor. Toilets shall be located a minimum of 50 feet
away from any inlet or water source.
Dumpsters and waste piles shall be located a minimum of 50 feet away from any inlet or water
source and shall be secured appropriately.
1.10 Dewatering
It is anticipated that the project site will not involve groundwater and stormwater dewatering
practice and hence any scope of spills is minimal
1.11 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.
1.12 Seeding and Mulching
Proposed seeding and mulching shall be per the approved landscape plan.
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
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2.0 Construction Sequence:
A construction schedule has not yet been completed due to the project being in the entitlement
stage. A construction sequencing chart for construction activities is provided in Table 1 below and
on the drainage and erosion control plan.
Table 1: Sequencing Chart
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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: 11‐11‐15
Itemized Costs:
Item Unit Quantity Unit Cost Total
Silt Fence LF 880 $ 2.00 $ 1,760.00
Inlet
Protection LF 35 $ 4.00 $ 140.00
Sed. Bas. EA 1 $ 2,500.00 $ 2,500.00
VTC EA 1 $ 2,000.00 $ 2,000.00
Subtotal $ 6,400.00
Multiplier 1.5
Total $ 9,600.00
Formula Based:
Unit Quantity Unit Cost Total
Revegetation AC 1.57 $ 1,500.00 $ 2,355.00
Multiplier 1.5
Total $ 3,532.50
Escrow Security (greater of two estimates, $ 3000.00 min.) $ 9,600.00