HomeMy WebLinkAboutDrainage Reports - 07/02/2018 (2)North Star
design
700 Automation Drive, Unit I
Windsor, CO s0550.
Phone: 970-686-6939
Fax: 970-686-11H
April 30, 2018
Heather McDowell
City of Fort Collins Stormwater
700 Wood Street
Fort Collins, CO 80522-0580
City of Fort Coll ns Approved Plans
ee
"Mimed by.
Date:
13E; Drainage Addendum to the "Final Drainage Report for the Seventh Filing of
the Centre for Advanced Technology"
700 Centre Avenue
Dear Heather,
I am pleased to submit this drainage addendum in conjunction with the minor amendment for this
site for your review and approval. This drainage addendum serves to summarize the drainage
design of the Summitstone Health Partner project. This letter will detail the effect of the proposed
improvements for the site and show that the site complies with the drainage concepts and designs
presented in the.previous studies for this site.
This addendum has been prepared in conformance with the Fort Collins Stormwater Criteria
Manual with exceptions made for the circumstance that this project is being processed as a minor
amendment. I certify that this report for the drainage design was prepared 'in accordance with the
Master Plan and the criteria in the City of Fort Collins Storm Drainage Manual.
I appreciate your time and consideration in reviewing this submittal. Please call if you have any
questions.
Sincerely,
Patricia Kroetch, P.E
The Summitstone Health Partners project is a Minor Amendment to the Centre for Advanced
Technology Seventh Filing which was designed and detailed in the plans and report completed by
RBD Engineering Consultants dated August51 1988. This site -is located on Tract of that original
plat. In the time since those plans were approved, changes have been made to the site design on
Tracts A and C which have been detailed in multiple plan sets and drainage reports and addendums
most notably, Amended Master Drainage Plan for the Centre for Advanced Technology (dated
February 1987), The Centre Avenue Residences (A replat of Tracts A and C) by Northern
Engineering dated October 13, 2009, The Arrowhead Cottages (a replat of Centre Avenue
Residences) by Northern Engineering dated August 2016, and The Centre for Advanced
Technology Fourteenth Filing. The drainage plan for this proposed project will conform to these
previously approved reports.
Historically, the majority of the site sheet flowed north and west to an existing detention pond
located in the northwest portion of the site. The proposed site will follow similar drainage.patterns
as the historical drainage patterns. The majority of the site basins will be collected in the parking
lot and routed to the detention pond via pans and curb openings or direct discharge into the
detention pond as has historically occurred.
A summary of the onsite basins continue below.
Basin A is the east half of the existing parking lot. This basin is being modified slightly as 3
additional parking stalls are being added in the northeast comer of the parking lot. The runoff will
flow to a 2' curb opening as it has historically done and enter the detention pond.
Basin B is the west half of the existingparking lot. This basin is being modified slightly as the
loading area is being removed from the northwest portion of the parking lot. The runoff will be
1 collected in a 4' concrete pan and flow north to a 2' curb opening and enter the detention pond as
it has historically done.
Basin C is the west most portion of the site which includes all of the existing building on site and
the proposed building addition. The flow patterns for this basin are around the west side of the
' building and flowing north into the detention pond. This drainage pattern will be maintained with
the roof runoff from the proposed addition being collected in underground pipes and conveyed to
the detention pond.
Basin D is the undeveloped area of the site that contains the New Mercer Ditch. Runoff from this
basin enters the New Mercer Ditch and does not enter the detention pond. No changes to this basin
are proposed.
Stomiwater detention is provided by an existing detention facility constructed with the Seventh
Filing of the Centre for Advanced Technology and certified with the Final Drainage and Erosion
Control Report for Centre Avenue Residences. This pond is shared with the Arrowhead Cottages
site which is adjacent to the west of this site and the CAT Filing 14 site which is northwest of the
Arrowhead Cottages. The original design for this pond included a total area of 7.81 acres which
includes Basins D2, D3 and Worthington Circle with all basins having a minor C-value of 0.71
and a major (100 year) C-value of 0.89 (0.71*1.25). The revision to the drainage report included
with the Arrowhead Cottages development shows a composite minor C-value of 0.51 and a major
C-value of 0.72.
The Summitstone site has an existing minor C-value of 0.62 and a major C-value of 0.77. The
proposed site will have an increase of 1,753 square feet of imperviousness which will increase the
imperviousness from 48% to 50%. These values were used to compile revised composite C-values
for the 7.81 acres (Basins D2 and D3) contributing to the detention pond. The revised composite
values for the 7.81 acres area 44.4% impervious and a.major c-value of 0.72. These values were
then used to recalculate the required water quality capture volume and the detention volume for
the pond. The water quality increases from 0.147 to 0.150 acre feet and the detention volume
remains the same at 1.44 acre feet which are negligible changes in the required volume for this
pond. For this reason, no increase to the existing detention pond sizing is proposed.
The proposed construction will disturb approximately 8,840 square feet which is below the
threshold of 10,000 square feet at which.additional erosion control design is required.
The detention pond will be modified to accommodate the building addition as a portion of this
addition encroaches on the existing detention pond. In order to minimize the impact of this
encroachment, a small landscape wall is being proposed along the portion of the building that is
adjacent to the pond.. The pond will also be expanded in two small areas in order to compensate
for the storage volume that is being removed for the building addition. It is anticipated that the
pond volume will remain at 1.44 acre feet at an elevation of 5046.35 NAVD 88 (elevation 504335
NGVD 29) as was determined in the Arrowhead Cottages drainage report. Calculations are
included at the end of this letter that show the impact of the increased imperviousness and the
modification of the existing pond. In summary, the impact of the proposed building expansion and
modifications to the site will have very minor impacts and the pond has been modified to
accommodate the encroachments.
In conclusion, this. addendum has been prepared. in accordance with the Fort Collins Stormwater
Criteria Manual and conforms to design completed with previous utility plans and drainage reports.
APPENDIX A
PROJEC
LOCATIO
VICINITY MAP
M ►1
HYDROLOGY CALCULATIONS
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APPENDIX C
DETENTION POND MODIFICATIONS
MODIFIED DETENTION VOLUME REQUIRED
FAA METHOD
(BASINS D2& D3,100-YEAR)
LOCATION: Summitstone Health Partners
PROJECT NO: 378-01
COMPUTATIONS', BY: PPK
SUBMITTED BY: North Star Design, Inc.
DATE: 4/30/2018
Equations_:
A trib. To pond =
7.81
acre
Qo = CiA
CIDO =
0.72
"* see below
V; = T"CIA = T*Qn
Developed C*A =
5 :6
acre
V. =K*QPo*T
QPo =
1.4
cfs
S=V; -Vo
K=
1
(from fig 2.1)
Rainfall intensity from City of Fort Collins IDF Curve
Storm
Duration, T
(min)
Rainfall
Intensity, i
(in/hr)
Qn
(cfs)
Vol. In
Vi
(ft)
Vol. Out --
V.
(f f')
Storage
S
(4)
Storage -
S
(ac-ft)
5.
9.95
56.0
16785
-420
-16365
0.376
10
7.72
434
26047
840
25207
0.579
20
5.60
31.5
37788
1680
36108
0.829
30
4.52
25.4
.45750-
2520.
43230
0.992
40--_-..
_ .-3.74
.21.0
50474
3360
47114
1.082
50
3.23
18.2
54489
4200
50289
1.154
60
2.86
16.1
57896
5046
52856
1.213
70
2.62 _
_ _ ._ 14.7_ -_ __
- - . 61878
5880,
55998
1.286
80
2.38
13A
64239.
__6720--
- -57519
1.320
90
2.22
12.5
67411
7560
59851
1.374
100
2.05
11.5
69165
8400 _ _
._ 60765_ _
1395
110__-__
_ _-1.93 - _
_ 10.9.
71628
9240
62388
1.432
120
1.80
10.1-
72877
10080
62797
1.442
130
1.60
9.0
70178
10920
59258
1.360
140
1.40
7.9
66129
11760
54369
1.248
150
1.20
6.7
60731
12600
48131
1.105
160
1.15
6.5
62080
13440
48640
L117
170
1.10
62
63092
14280
48812
1.121
180
1.05
5.9
63767
15120_ _
_ 48647
_ 1.117__
Required Storage Volume: 62797 f?
1A42 acre-ft
* * (1.5 acres at 0.77 + 6.31 acres at 0.71) / 7.81 acre: = 0.72
cc
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' STAGE -. STORAGE TABLE
(100-YEAR)
LOCATION: Summitstone Health Partners
PROJECT NO: 378-01
'CALCS BY: PPK
SUBMITTED BY: North Star Design, Inc.
DATE: 4/20/2018
EXISTING POND
WQC Volume Required= 0.147
100 yr Detention Volume Required = 1.446
(On NGVD 1929 datum)
Stage
(ft)
Surface
Area
(ft)
Incremental
Storage
(ac-ft)
Total
Storage
(ac-ft)
5039.20
645.33
_ _
5039.40
2450.42
0.007
-0'.007
5039.60
5291.24
0.017
0.024
5039.80
7639.85, _
0.030 _
0.054 _
5040.00
9359.05,
0:039
0.093
5040.20
10856.29
-0.046
0.139
5040.23
11008.61
0.608
0.147
5040.40.
11808.30
0.052
0.191
5040.60
12559.23
0.056
0.247
5040.80
13148.15
0.059
0.306
5041.00
14013.52
0.062
0.368_
5041.20
14680.01
0.066
0.434
5041.40
15433.82
- 0.069
0.503
5041.60
16171.07
0.073
0.576
5041.80
17156.13_.
_ 0.076.-.
_ 0.652
5042.00
18654.88
0:082
0.734
5042.20
20134.80
0.089
0.823
5042.4.0
21217.82
0.095
0.918
5042.60
22292.83
--0:100K1.445
5042.80
23490.37
_ 0_105_ _5043.00
24775:61
0.1115043.20
26171.89
0.117
5043.35
27239.15
0.0945043.40
27557.94
0.123
-=WQCV
100 yr HWEL
MODIFIED POND
WQC Volume Required= 0.149
100 yr Detention Volume Required = 1.442
(On NAVD 1988 datum)
To convert from 1929 datum_ add 3.19'
Stage
(ft)
Surface
Area
(ftZ)
ldcremefiti
Storage
_ (ac-ft)_
--Tota1
Storage
_ .(ao-ft)
5042.38
. - 645.33
5042.58
2450.42
0.007
0.007
5042.78
5291.24
0.017
0.024
5042.98.
7639.85
0.030
0:054
5043a-18
9359105
0.039
0.093
-5043.38
10856.29
0.046
0.139
5043.42
11046.69_ -
0.010
0.149
5043.58
11808.30
0.052
0.191
5043.78
12559.23
0.056
0.247
5043.98
13148.15
0.059
0.306_ _
5044.18
14013.52
0.062
0.368
5044.38
14680.01
0.066
0.434
5044.58
15433.82
0.069
0.503
5044.78
_ 16171.07
0.073
0.576
5044.98
17156.13
0.076
0.652
5045.18
18654.88
0.082
0.734
504538
20134.80
0.089
0.823
5045.58
21217,82
0.095
0.918
5045.78
22292.83
0.100
1.018
5045 98
:.. 23703.95 ;;
0406
= .. 1.124-
5046 18.
-:. 24861.31':' :
_. 0.111 ""
5046 38!
"; 26018.68 :
G 0 117
2:5046.53
26909:85
0.094 '
:" :;1:446
.504658.'<2717604_i
. 0122__
:_. 1474
Modified values, (dueto.ret wall),have been shaded
c=WQCV
=100 yr HWE
Final Drainage and Erosion Control Report
for
Centre Avenue Residences
(Being a Re -plat of Tract A and Tract C, Centre for Advanced Technology P.U.D., Se nth Filing)
Fort Collins, ColoOb of Ft Coffinsp, Mans
Approved By
PRO PMTY 07F Date
p=-r eojj2?.«YT, j1TyQpPPO 3, 2009
Prepared for
Mr. Stan Everitt
Everitt Companies
3003 East Harmony'Road, Suite 400
Fort Collins, Colorado 80528
Prepared by:
NORTHERN
ENGINEERING
200SO=C011epAwm. Swm 100
FW. Cu ins, Calm do 80524
P .e 970.221.4158 F.;970.221.4159
...Mmmwwneomig;�nm
Project Number: 110-034
,loaded on
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APPENDIX D
EROSION CONTROL SURETY
Erosion and Sediment Control Escrow/Security Calculation
for The City_ of Fort Collins
Project: SUMMITSTONE HEALTH. PARTNERS
Disturbed Acres: 0.21
EROSION CONTROL BMPs
Units
Quantity
Price
Price
Silt Fence
L.F.
302
$3.00
$906.00
Rock Sock
each
6
$85.00
$510.00
Rock Berm
each
0
$220.00
$o.ob
Vehicle Tracking Control Pad
each
1
$1,500.00
$1,500.00
Concrete Washout
each
1
$1,200.00
$1,200.60
Inlet Protection
each
0
$210.00
$0.00
Sub -Total: $4,116.00
1.5 x Sub -Total: $6,174.00
Amount of security. $6,174.00
" Reseedln
g
Amount
Total Acres x Price/acre: $252.00
Unit Price of Seeding per acre: $1,200.00
Sub -Total: $252.00
1.5 x Sub -Total`. $378.00
Amount to Re -seed: $378.00
Minimum escrow amount:
"The amount ofthe security must be base/ on one and one-half dines the es imale ofthe cast to install the approved measures, or one and one-half times
the cost to re -vegetate the disturbed land to drylandgmases based upon unit cost determined by the City'sAnnual Revegetadon and Stabilzadon Bid,
whichever lsgreoter. In no instance, will the a amount afsecurlty be fens than one thoumnd five hundred d0Bars($1,500) for residemial developmem or three
thousand dollars ($3,000) for commercial development"
10/26/2017 3:54.PM NM7M1 summusmmloi�napelEmabnsiaw.x,
APPENDIX E
EROSION & SEDIMENT CONTROL REPORT
O EROSION & SEDIMENT CONTROLS
1.0 Written Analysis
An Erosion and Sediment Control Plan is included herewith It should be noted, however,
that any such Erosion and Sediment Control Plan serves only as a general guide to the
Contractor. Staging and/or phasing of the BMPs depicted, and additional or different BMPs
from those included may be necessary during construction, or as required by the authorities
having jurisdiction.
It shall be the responsibility of the Contractor to ensure erosion control measures are
properly maintained and followed. The Erosion and Sediment Control Plan is intended to
be a living document, constantly adapting to site conditions and needs. The Contractor shall
Qupdate the location of BMPs as they are installed, removed or modified in conjunction with
construction activities. It is imperative to appropriately reflect the current site conditions
n at all times.
The Erosion and Sediment Control Plan shall address both temporary measures to be
implemented during construction, as well as permanent erosion control protection. Best
Management Practices froth the Volume 3, Chapter 7 - Construction BMPs will be utilized.
n Measures may include, but are not limited to, silt fencing along the disturbed perimeter,
�A gutter protection in the adjacent roadways and inlet protection at proposed storm inlets.
a Vehicle tracking control pads, spill containment and clean-up procedures, designated
concrete washout areas, dumpsters, and job site restrooms shall also be provided by the
Contractor.
Grading, and Erosion Control Notes can be found on Sheet 2 of the Utility Plans. In addition
to this report and the plan sheets, the Contractor shall be aware of and adhere to the
applicable requirements outlined all Development Agreements pertaining to this property.
Also, the Site Contractor for this project will be required to secure a Stormwater
Construction General Permit from the Colorado Department of Public Health and
Environment (CDPHE), Water Quality Control Division - Stormwater Program, before
commencing any earth disturbing activities. The Contractor shall also develop a
comprehensive .Storm Water Management Plan (SWMP) confonning to applicable
requirements including descriptions of the ongoing activities, inspections and maintenance
- . of construction BMPs.
QThe site is approximately 1.50 acres and approximately 9300 square feet of which will
a undergo earthmoving operations. The existing site has an existing building, parking lot and
landscaping cover approximately 75% of the site and an irrigation ditch that covers
approximately 20% of the site.
Runoff from this site currently discharges into an existing detention pond and the
improvements will continue this runoff pattern.
a The soils on this site are classified by the USGS Soil Survey as Nunn Clay Loam and are
classified in the hydrologic group C. These soils are characterized as having a slow
infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that
impedes the downward movement of water or soils of moderately fine texture or fine
texture. These soils have a slow rate of water transmission. The rainfall erodibility is
deemed to be moderate and the wind erodibility is deemed to be moderate to high.
The site is surrounded by developed sites including streets, buildings and paved areas. The
construction shall utilize silt fence around the perimeter to control sediment transport from
rainfall and from wind. The silt fence that is located in the proposed pavement areas will
0 be removed prior to placing new pavement. Rock socks will be utilized in the existing curb
and detention pond to capture sediments that are not fully contained by the silt fence
placement. The locations of the rock socks will be in the areas of concentrated flow such
as in the existing curb and on the concrete pans.
The site will also utilize a vehicle tracking control pad to minimize sediment from being
tracked onto adjacent pavements. Sediment that is tracked will be removed and placed
Within the site or permanently disposed of offsite. A concrete washout.will be used on.site
during the concrete placement. All hardened concrete will be disposed of offsite. These
BMP's have not been located on the site map due to the fact that the site is very small and
these BMP's will need to be placed by the contractor in locations that are most beneficial
and will minimize disruption of adjacent traffic.
Permanent erosion control consists of covering the soils with a building, concrete walks,
concrete pavement, recycled asphalt pavement and sod. No soil will be left exposed to
erosion after the construction is complete. Refer to the landscape plan for areas of and
instructions for placement of sod and soil amendments required prior to placement of sod.
Refer to Appendix D for the Erosion Control Surety calculations.
2.0 SWMP contact information
Permit holder:
Name:
Address:
Phone Number:
Email Address:
APpoifited agent:
Name:
Address:
Phone Number:
Email Address:
3.0 Identification and location of all potential pollution sources
Potential Pollutant Source'Acttvrty^
7777
Potential Poili}tant
-- Generated
Apphca6le to
—this project
Control Measure
Disturbed Areas
Sediment
X
Silt Fence, RockSocks
Soil stockpiles
Sediment
X
Silt Fence; Rock Socks
Travel to adjacent public streets
Tracked sediment
X
Tracking Pad; street sweeping
Contaminated soils
Sediment, chemicals
Possible
Remove contaminated'soils
from site **
Loading and unloading chemicals
Chemicals
Unloading of building materials
Trash, debris
X
Trash dumpsters, Waste
Management Firm
Outdoor storage of chemicals
Chemical's
On site equipment maintenance
Oil, grease
On site equipment fueling
Diesel, gasoline
X
Containment berm **
Dust generating activities
Particulates, sediment - -
- X
Water (ruck
Use of fertilizer, pesticides, herbicides
Fertilizer, pesticides
Use of detergents, solvents, oils
Detergents, solvents, oil
X
If spilled, remove
contaminated soils from site
*s
Waste dumpsters, waste piles
Chemicals, trash, debris
X
Waste Management Firm
Concrete washout
Concrete, sediment, wash
water
X
Remove hardened concrete,
dispose of offsite **
On site equipment washing
Detergents, oil
On site asphalt batch plant
Asphaltic cement, sediment
On site concrete batch plant
Cement, sediment
Portable toilets
Domestic sewage
X
Waste Management Firm
** Refer to Section 1.5.2 for additional Materials Handling & Spill Prevention BMP
4.0 Best Management Practices (BMP's) for Stormwater Pollution Prevention
Structural Practices for Erosion and Sediment Control
Structural practices for the site will consist mainly of silt fence and rock sock filters and
are described in detail in the following paragraphs. These BMP's are expected to change as
the construction progresses and it is the responsibility of the contractor to ensure
appropriate BMP's are in place and/or removed at the appropriate time in the construction
sequence. All temporary and permanent erosion and sediment control practices must be
maintained and repaired as needed to assure continued performance of their intended
function.
Silt fence and rock sock filters shall be in place prior to commencement of construction
activities, During clearing and grubbing necessary for silt fence installation, all cleared
material shall -be placed -on the -uphill side so that if erosion occurs from the "cleared
material, the sediment will be trapped and not transported downstream. Rock socks shall
be implemented in the existing curb line as shown on the Drainage & Erosion Control Plan.
All BMP's shall be installed per the details shown on the construction plan set
QTemporary & Permanent Structural BMP's:
Structural BMP
m Approximate IocaUon on site
Apphcable'to this',
Project.:; '
Silt Fence
Site perimeter, refer to site map
X
Straw bale dams
Rock Socks
At existing sidewalk culverts, in existing
gutters, refer to site map
X
Earthen -diversion dams
Vegetated swales
Sediment trap/pond
Pipe slope drains
Geogrid
Inlet/outlet protection
In the detention Pond
X
Culverts
Refer to site map
X
Riprap
Erosion control mats
Inlet protection
Vehicle Tracking Control Pad
At site entrance, refer to site map
X
Concrete Washout
To be located by Contractor
X
Non -Structural Practices for Erosion and Sediment Control:
Soils exposed during the earthwork phase and landscape prep phase shall be kept in a
roughened condition by ripping or disking along land contours until mulch, vegetation, or
other permanent erosion control is installed. No large amount of soils (in excess of 15
yards) will be allowed to be stock piled on site. Overburden from the utility pipe trenching
Will be piled adjacent to trenches upstream of sediment controls and will be replaced in the
trenches within 12 hours.
Excess excavated materials from the demolition and grading phases of the project that
cannot be reused on site will be exported as it is. excavated. This includes any asphalt
pavement from the existing site that is to be removed.
A vehicle tracking pad will be installed at a location most beneficial to the site construction
as determined by the contractor. Vehicles will not be permitted in the excavated area if
soil is muddy. Gravel sub base will be placed and compacted in the areas indicated for
pavement following excavation. In the current pre construction state the site enables
tracking of silt onto the adjacent streets during wet conditions. During construction
activities the street will be monitored for foreign debris tracked out of the site and
mechanical sweeping and clean up will be performed as needed.
u No area shall remain exposed by land disturbing activity for more than thirty (30) days
before required temporary or permanent erosion control (e.g. seed/mulch, landscaping,
li etc.) is installed,
Temporary & Permanent non-structural BMP's:
Non -Structural BMP
A ioximate location on site's
pp
Apphcalile t6 this ,"
Prolecf
Surface roughening
Soil stockpile height limit (less than
--
10')
'
Perimeter vegetative buffer
All boundaries of site
X
Minimization of site disturbance
Mulch
-
Seed & mulch stockpiles after 30
days
Stockpile toe protection (silt fence,
wattles or ditch)
Preservation & protection of existing
All boundaries of site
X
vegetation & trees
Good site housekeeping (routine
Entire Site
X
cleanup of trash & constr debris)
Sweeping & scraping of hardscape
On and off site pavements
X
areas
Heavy equip staged on site, properly
maintained & inspected daily (no
Staging area
X
onsite maintenance)
I5.0B..MP Implementation
5:1 Phased BMP Implementation
BMP's are expected to change as the construction progresses and it is the responsibility of
the contractor to ensure appropriate BMP's are in place and/or removed at the appropriate
time in the construction sequence. A construction sequence schedule has been included on
the Drainage & Erosion Control Plan and included in the construction plans
lans for this site.
All BMP's shall be inspected and repaired or replaced as required to satisfy the conditions
of the Stormwater Discharge Permit. All BMP's must be maintained and repaired as
needed to assure continued performance of their intended function. Refer to Appendix E
for the BMP schedule and estimated costs..
5.2 Materials Handling and Snill Prevention-
Materials Handling & Spill Prevention BMP
Approximaterlocidon on site
AOpli6abl6'to V.
,
hi *
t sPrb , ject:--,,
Portable toilets, anchored & located away from
drainages
Contractor to determine
X
Fuel storage located in bulk tanks with secorkdary
containment & spill kit
Mobile fueling performed at least 200 feet away from
drainages & fully attended
Contractor to determine
X
Fertilizers, form oil, solvents, cleaners, detergent
stored in 55 gal or smaller containers, kept in storage
Contractor to determine
X
units
Dumpsters containing used chemicals containers &
liquid wastes kept covered
Contractor to determine
X
Equipment cle*ng (on site) uses no detergents &
flows to onsite retention basin
In case of a rele6e of fuel or other chemicals,
absorbent booms or earthen berms will be
immediately' - - constructed to contain the spill &
Location of spill
X
prevent runoff to adjacent surface waters
MSDS sheets for onsite chemicals will be kept at the
construction trailer to facilitate spill response &
Contractor to determine
X
cleanup
5.3 Dedicated Asphalt or Concrete Batch Plant:
Not proposed with this development
5.4 Vehicle Tracking Pad:
Vehicle tracking control pad shall be installed wherever construction vehicle access
- - --- - -- - _ _. _ -- -- -- - - -
routes intersect paved public roads. Vehicle tracking control pads shall be installed to
minimize the transport of sediment (mud) by runoff or vehicles tracking onto the paved
surface. Any mud tracked to public roads shall be removed on a daily basis and after any
significant storm that causes sediment to be transported. It is unlawful to track
sedimentimud onto public streets and may be enforced by the City of Fort Collins, by the
State of Colorado or by the EPA.
5.5 Waste Management and Disposal:
Portable toilets will be anchored & periodically maintained by waste management
company.Dumpsters on site will be covered & periodically emptied by waste management
company. Concrete waste will be allowed to harden and then will be removed from site.
No washing activities will occur on site.
' Location of the concrete washout is shown on the site map. The washout will be sufficiently
deep to accommodate all anticipated concrete truck wash water. Waste concrete will be
allowed to harden and be removed from site periodically as the washout reaches 50% of its
capacity. Truck wash water will not be allowed to reach the curb & gutter or any other
water course.
5.6 Groundwater and Stormwater Dewatering:.
No groundwater was encountered during soils exploration therefore ground water is not
anticipated to be an issue: If groundwater is encountered a groundwater discharge permit
shall be obtained and a detailed report shall be completed describing the location and the
route of where pumped groundwater will be conveyed and the measures taken to prevent
the transport of any pollutants to downstream waters.
5.7 Inspection & Maintenance.
It is required that routine site inspections are performed to effectively address maintenance
and repair of Best Management Practices (BMP's). The site inspections are to performed
t by the contractor or an inspector designated by the administrator at a minimum of once
every fourteen (14) calendar days on active construction sites and after any significant
storm event (an event causing runoff). As part of the site inspections the inspector is
required to keep documentation of all inspections and BMP maintenance, including an
updated Site Map indicating new BMP's or the removal of BMP's since the previous
' inspection.
' Any maintenance, repair, or necessary installation of BMP's that are noted during the
inspection must be completed within seven (7) calendar days from the date of the
inspection.