HomeMy WebLinkAboutReports - Erosion Control - 04/18/2025
EROSION CONTROL
REPORT
UPLIFT SELF STORAGE
AT RUDOLPH FARM
Fort Collins, CO
PREPARED FOR OWNER/DEVELOPER:
UPLIFT DEVELOPMENT, LLC
5388 Ronald Reagan Blvd., Unit 136
Johnstown, CO 80534
Phone: 970‐420‐1521
Contact: Tony Ollila
Email: tony@upliftdg.com
PREPARED BY:
KELLY DEVELOPMENT SERVICES, LLC
9301 Scrub Oak Drive
Lone Tree, Colorado 80124
Phone: 303‐888‐6338
Contact: Greg Kelly, PE
Email: greg@kellydev.com
CONTRACTOR:
TBD
EROSION CONTROL ADMINISTRATOR:
TBD
April 18, 2025
“THIS EROSION CONTROL REPORT HAS BEEN PLACED IN THE CITY OF FORT COLLINS FILE FOR THIS
PROJECT AND HAS BEEN DETERMINED TO COMPLY WITH THE APPLICABLECITY OF FORT COLLINS
STORMWATER MANAGEMENT CRITERIA. ADDITIONAL STORMWATER MANAGEMENT, EROSION AND
SEDIMENT CONTROL MEASURES MAY BE REQUIRED OF THE OWNER OR HIS/HER AGENTS, DUE TO
UNFORESEEN EROSION PROBLEMS OR IF THE SUBMITTED PLAN DOES NOT FUNCTION AS INTENDED.”
“REVIEW OF THIS PLAN BY THE CITY OF FORT COLLINS SHALL NOT IMPLY THAT IT HAS BEEN REVIEWED
FOR COMPLIANCE WITH THE REQUIREMENTS SET FORTH BY THE STATE OF COLORADO DEPARTMENT
OF PUBLIC HEALTH AND ENVIRONMENT GENERAL PERMIT FOR STORMWATER DISCHARGES
ASSOCIATED WITH CONSTRUCTION ACTIVITY.”
“SEE APPROVED EROSION CONTROL PLAN DESIGN DRAWINGS FOR SITE SPECIFIC BEST MANAGEMENT
PRACTICES.”
Project Owner/Developer Signature Block
I have reviewed the information contained within the Erosion Control Report and accept responsibility
for the requirements set forth.
Permittee/Affiliation Date
Uplift Development Group, LLC
Plan Preparer Signature Block
I acknowledge my responsibility for the preparation of the Erosion Control Report.
CO Professional Engineer Date
Greg S. Kelly, P.E
TABLE OF CONTENTS
I. PROJECT LOCATION
II. EXISTING SITE CONDITIONS
III. PROPOSED CONSTRUCTION ACTIVITIES
IV. POTENTIAL POLLUTANT SOURCES
V. CONSTRUCTION CONTROL MEASURES
VI. INSPECTION AND MAINTENANCE
VII. FINAL VEGETATION AND STABLIZATION
VIII. APPENDICES
1
I. PROJECT LOCATION
1. Vicinity Map
FIGURE 1
2. The overall Rudolph Farm project site is located in a tract of land located in Section 15,
Township 7 North, Range 68 West of the 6th Principal Meridian, City of Fort Collins, County of
Larimer, State of Colorado.
3. The Uplift Self Storage project site is located on Lot 11 of the Rudolph Farm Subdivision, just
north of the Timnath Reservoir Inlet Canal (TRIC) along the proposed Carriage Parkway.
II. EXISTING SITE CONDITIONS
1. The site area is 3.07 acres, bordered on the west and north by Carriage Parkway, TRIC to the
south, and Prospect Middle/High School property to the east. Onsite disturbed area is 1.82
acres, offsite disturbance area for drive connections and utility service connections is 0.10
acres.
2. The site is part of the Official Development Plan (ODP) and Infrastructure Final Development
Plan (FDP) for Rudolph Farm. All detention, standard water quality, LID, and all associated
storm water infrastructure will be installed with the overall developer infrastructure FDP
improvements.
2
3. The site is vacant farm land. Per the NCRS Soils Report (copy in report appendix), the site is
comprised of Garret loam (Hydrologic Soil Group B), Fort Collins loam (Hydrologic Soil Group
C), with some Nunn clay loams (Hydrologic Soil Group C).
4. The site is not within a FEMA 100‐year floodplain as shown on Flood Insurance Rate Map
Number 08069C1003G (included in the Appendix of this report) as a LOMR was approved by
FEMA on February 21, 2019 (Case No. 17‐08‐1354P) removing the majority of Rudolph Farm
from the floodplain.
5. No vegetation will exist on the project site at the commencement of the project as the overall
development will be mass graded.
6. Groundwater levels were encountered at varying depths of 4’‐10’ below existing grade,
approximately 10’ below the finished floor of the proposed building. Since the site is a fill site,
no dewatering is expected.
7. Slopes are mild, maximum being 4:1.
8. The NHBZ abuts the south property line as noted on the plans.
III. PROPOSED CONSTRUCTION ACTIVITIES
1. The proposed development will be in two Phases: Phase 1 will be a 3‐story climate‐controlled
building with a footprint of 34,075‐sf. Phase 2 will be a total of 13,860‐sf of single‐story self‐
storage, including one 6,650‐sf climate controlled building. Also proposed are access drives
with parking and landscaping. Construction activities include grading, building construction,
utility services installation, storm sewer construction, paving and landscaping.
2. Site stormwater discharge will be routed into the overall development water quality and
detention facility. Ultimate receiving waters of the entire development is the Poudre River via
storm infrastructure constructed by others.
3. Total site area is 3.07 acres. The Phase 1 disturbance area is 1.82 ac onsite and 0.10 ac offsite.
4. Staging and storage areas will be located on the north side of the site construction area,
approximately 4,500 sf in size.
5. The site is a fill (import) site, anticipated volume of 4,500 cy.
6. Because the site is greater than 1.0 ac of disturbance and part of a larger common
development, a State Discharge Permit will be required.
7. Erodibility of the site will be mitigated through good compaction and dust control practices.
3
IV. POTENTIAL POLLUTANT SOURCES
Potential
Pollution
Source
Potential
on this
site?
Control Measures (CM) CM Implementation (as needed)
Disturbed &
Stored Soils
‐ grading
‐ spoils
‐ stockpiles
Yes
ESC CMs (IP, SF, SSA, TRM,
RECP, TOP, SCL, SBB, RS, SB, ST)
Preservation of existing
vegetation (PV, VB, CF, CP)
Materials management
Solid waste management (SP,
GH)
Stockpile management (SP)
Vehicle tracking control (VTC)
1. Delineate protected areas prior to
construction.
2. Install CMs prior construction.
3. Manage materials effectively once
they arrive on site.
4. Place trash receptacles prior to
construction.
5. Implement spill response.
6. Implement stockpile mgnt controls.
7. Delineate vehicle travel areas prior
to construction, adjust as needed.
Vehicle
Tracking
‐ all permitted
vehicle traffic
Yes
ESC CMs (IP, SF, SSA, TRM,
RECP, TOP, SCL, SBB, RS, SB, ST)
Vehicle traffic controls
Vehicle tracking controls (VTC)
Street sweeping (SS)
1. Install CMs prior construction.
2. Delineate vehicle travel areas prior
to construction, adjust as needed.
3. Install VTC prior to construction.
4. Implement SS as needed, in
conjunction with start of
construction.
Contaminated
Soils No
Hazardous materials
management (GH, CT)
Spill response & notification
(GH)
Stockpile management (SP)
1. Implement hazardous materials
management.
2. Implement spill response
procedures.
3. Implement stockpile mgmt.
controls.
Loading &
Unloading
‐ construction
materials
Yes Material management (GH)
Vehicle traffic controls (VTC)
1. Manage materials effectively once
they arrive on site.
2. Delineate vehicle travel areas prior
to construction, adjust as needed.
Vehicle/equip
ment maint. &
fueling
‐ gas, oil,
‐ diesel
‐ lubricants
‐ hydraulic fluids
Yes
Spill prevention controls (GH)
Designated fuel storage area
(GH)
Spill response & notification
(GH)
1. Designate fuel storage area.
2. Implement spill prevention
controls.
3. Implement spill response and
notification procedures.
Outdoor
storage
‐ building
materials
‐ fertilizers
‐ chemicals
Yes Material storage procedures
(GH)
1. Designate material storage areas
prior to delivery.
2. Materials left outdoors must be
covered if they can pollute
stormwater.
3. Secondary containment must be
used for hazardous materials.
4
Dust
‐ wind transport
‐ saw cutting
Yes
Dust control (DC)
Temporary soil stabilization (SF,
SD, GB, SSA, TRM, RECP, TOP)
Street sweeping (SS)
Preservation of existing
vegetation (PV, VB, CF)
1. Delineate protected areas prior to
construction.
2. Implement dust control in
conjunction with soil disturbing
activities.
3. Implement temporary soil
stabilization measures as soon as
practical.
4. Implement street sweeping at the
start of major construction and
maintain as needed.
Routine
Maintenance
Activities
‐ fertilizers
‐ pesticides
‐ detergents
‐ solvents
‐ fuels, oils, etc.
Yes
Material storage (GH)
Hazardous waste management
(GH, Chemical Treatment)
ESC CMs (IP, SF, SSA, RECP,
TOP, SCL, SBB, RS, SB, ST)
1. Designate materials storage areas
prior to site arrival.
2. Practice hazardous waste
management procedures during
the storage of such materials.
3. Install ESC measures prior to
landscape work.
Non‐industrial
Waste
‐ worker trash
‐ portable toilets
Yes Sanitary waste (GH)
Solid waste management (GH)
1. Place temporary sanitary facilities
on site and prevent off‐site discharges.
2. Place trash receptacles on site.
On‐site
Industrial
Waste
‐ construction
debris, etc
Yes
Waste management (GH)
Liquid waste management (GH)
Hazardous waste management
(GH, CT)
1. Place trash receptacles on site.
2. Place designated watertight
receptacles or washout area(s) prior
to activities that produce liquid waste.
3. Implement hazardous waste
management procedures.
Concrete
Truck
Chute/Tool
Washing
Yes Concrete washout area (CWA) Install designated concrete washout(s)
prior to concrete work.
Drywall Mud
and Paint Yes Liquid waste management (GH)
Place designated watertight
receptacles or washout area(s) prior
to activities that produce liquid waste.
Fly Ash
‐ concrete
‐ flow fill
No
Concrete washout area (CWA)
Hazardous waste management
(GH)
1. Install designated CWA prior to
concrete activities.
2. Implement hazardous waste
management procedures.
Dedicated:
‐ Asphalt
Plants
‐ Concrete
Batch Plants
‐
Mortar/Maso
nry Mixing
Stations
No
Secondary containment
Concrete washout area (CWA)
Solid waste management (GH)
materials management (GH)
1. Install secondary containment CMs
prior to using dedicated batch
plants.
2. Establish dedicated washout area
before construction begins.
3. Place trash receptacles on site.
4. Manage materials effectively once
they arrive on site.
5
Waste from:
‐ Geo‐tech
Test
‐ Potholing
‐ Saw Cutting
‐ Utility
borings for
locates
No
Dust control (DC)
Material storage (GH)
Solid waste management (GH)
1. Implement dust control in
conjunction with soil disturbing
activities.
2. Designate materials storage areas
prior to their arrival on site.
3. Place trash receptacles on site.
Demolition of
infrastructure:
‐ concrete
curb
‐ asphalt road
‐ steel/rebar
No Dust control (DC)
Solid waste management (GH)
1. Implement dust control in
conjunction with soil disturbing
activities.
2. Place trash receptacles.
Electric
Generator
‐ pump
No
Secondary containment
Spill response & notification
(GH)
Hazardous waste management
(GH, CT)
1. Install secondary containment CMs
prior to using generators.
2. Implement hazardous waste
management procedures.
Areas where
potential spills
can occur
Yes
Hazardous waste management
(GH)
Spill response & notification
(GH)
1. Implement hazardous waste
management.
2. Implement spill response and
notification procedures.
Flushing
Waterlines No
ESC CMs
Low Risk Guidance for Potable
Water **See Appendix 12
1. Install ESC measures prior to
discharge.
2. Follow CMs required by the Low
Risk Guidance**See Appendix 12
6
V. CONSTRUCTION CONTROL MEASURES (BMPs)
BMP Description: Silt Fence
Intended Use/Purpose: Perimeter sediment control
Appropriate Installation
Timing:
Prior to land disturbance operations
Appropriate Removal
Timing:
Upon final site stabilization
BMP Description: Vehicle Tracking Control
Intended Use/Purpose: Prevention of sediment transport onto existing roadways and into
storm sewers
Appropriate Installation
Timing:
Prior to land disturbance operations
Appropriate Removal
Timing:
Immediately prior to paving
BMP Description: Inlet Protection
Intended Use/Purpose: Prevent sediment from entering detention ponds
Appropriate Installation
Timing:
Immediately after construction of inlet
Appropriate Removal
Timing:
Upon final stabilization
BMP Description: Stabilized Staging Area
Intended Use/Purpose: Prevent sediment transport onto public streets
Appropriate Installation
Timing:
Immediately after overlot grading and utility installation
Appropriate Removal
Timing:
Immediately prior to paving
7
BMP Description: Concrete Washout Area
Intended Use/Purpose: Prevention of concrete waste water or liquid concrete waste from
entering the groundwater or public streets
Appropriate Installation
Timing:
Prior to any concrete work on site.
Appropriate Removal
Timing:
Immediately prior to paving
BMP Description: Diversion Ditches
Intended Use/Purpose: Temporary stormwater conveyance to sediment control BMPs
Appropriate Installation
Timing:
Prior to any land disturbance operations
Appropriate Removal
Timing:
Upon final stabilization
BMP Description: Sediment Trap
Intended Use/Purpose: Capture eroded or disturbed soil transported in storm runoff.
Appropriate Installation
Timing:
Prior to any land disturbance operations
Appropriate Removal
Timing:
Prior to final grading for paving
BMP Description: Street Sweeping
Intended Use/Purpose: To remove accumulated sediment from public streets and prevent
transport to waterways.
Appropriate Installation
Timing:
Weekly or as needed, whichever occurs more frequently.
Appropriate Removal
Timing:
To be conducted until final site stabilization.
8
Phase Description: Dust Suppression
Intended Use/Purpose:
To prevent wind erosion.
Appropriate Installation
Timing:
As needed on site to prevent fugitive dust.
Appropriate Removal
Timing:
Applicable as long as land disturbance activities are occurring.
BMP Description: Temporary Seeding and Mulching
Intended Use/Purpose: To minimize wind and water erosion. See approved landscape
plans for Seed Mix
Appropriate Installation
Timing:
Any disturbed area that will be left open for more than 14 days
will be seeded and mulched
Appropriate Removal
Timing:
Upon final stabilization
BMP Description: Trash and Debris Removal
Locations Entire site.
Appropriate Installation
Timing:
As needed, the contractor will transport trash and debris off site
for proper disposal.
Appropriate Removal
Timing:
As needed.
BMP Description: Loading and Unloading
Intended Use/Purpose: To minimize contamination during the loading and unloading
process. Any loading and unloading of construction equipment or
materials shall be done in the stabilized staging area and not on
unprotected surfaces. If any spills occur the procedures outlined
above shall be followed.
Appropriate Installation
Timing:
See Stabilized Staging Area.
Appropriate Removal
Timing:
See Stabilized Staging Area.
9
VI. INSPECTION AND MAINTENANCE
1. Inspection Personnel:
Identify the person(s) who will be responsible for conducting stormwater inspections and
describe their qualifications:
TBD
2. Inspection Frequency:
Inspections shall start within 7 calendar days of commencement of construction activities.
Minimum Stormwater Inspection Schedule: A thorough inspection of the site inspection shall
be performed in accordance with one of the following minimum frequencies:
At least one inspection every 7 calendar days, or
At least one inspection every 14 calendar days, if post‐storm event inspections are conducted within 24
hours after the end of any precipitation or snowmelt event that causes surface erosion. Post‐storm
inspections may be used to fulfill the 14‐day routine inspection requirement.
Post‐Storm Inspections at Temporarily Idle Sites ‐ For permittees choosing to combine 14‐day
inspections and post‐storm‐event inspections, if no construction activities will occur following
a storm event, post‐storm event inspections must be conducted prior to re‐commencing
construction activities, but no later than 72 hours following the storm event. The delay of any
post‐storm event inspection must be documented in the inspection record. Routine
inspections must still be conducted at least every 14 calendar days.
Inspections at Completed Sites/Areas ‐ When the site, or portions of a site are awaiting
establishment of a vegetative ground cover and final stabilization, the permittee must conduct
a thorough inspection of the stormwater management system at least once every 30 days.
Post‐storm event inspections are not required under this schedule. This reduced inspection
schedule is allowed if all of the following criteria are met:
i. All construction activities resulting in ground disturbance are complete;
ii. All activities required for final stabilization, in accordance with the SWMP,
have been completed, with the exception of the application of seed that has
not occurred due to seasonal conditions or the necessity for additional seed
application to augment previous efforts; and
iii. The SWMP has been amended to locate those areas to be inspected in
accordance with the reduced schedule allowed for in this paragraph.
The minimum inspection frequency required does not affect the permittee’s responsibility to
implement and maintain effective control measures as prescribed in the SWMP. Proper
maintenance may require more frequent inspections.
10
BMP Maintenance or Inspection Description:
Sediment traps shall accumulated sediment removed when sediment depth equals one
foot.
BMP Maintenance or Inspection Description:
Perimeter silt fence, vehicle tracking control, diversion ditches, etc. repaired or replaced
as necessary.
BMP Maintenance or Inspection Description:
Silt fence shall be immediately refastened to the posts or replaced if not properly
fastened.
11
VII. FINAL VEGETATION AND STABLIZATION
Final vegetation and stabilization will be achieved per the approved site improvements of the Final
Development plan including paving, building construction, and the landscaping plan. Soil preparation,
planting methods and schedules will adhere to the approved landscaping plan.
VIII. APPENDICES
1. BMP Fact Sheets (Erosion Control Measures)
2. BMP Cost/Escrow Calculations
3. Soils Report
APPENDIX 1
BMP FACT SHEETS (EROSION CONTROL MEASURES)
MM-1 Concrete Washout Area (CWA)
CWA-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
setbacks infeasible or if highly permeable soils exist in the area, then the pit must be installed with an
impermeable liner (16 mil minimum thickness) or surface storage alternatives using prefabricated
concrete washout devices or a lined aboveground storage area should be used.
Design details with notes are provided in Detail CWA-1 for pits and CWA-2 for aboveground storage
areas. Pre-fabricated concrete washout container information can be obtained from vendors.
Maintenance and Removal
A key consideration for concrete washout areas is to ensure that adequate signage is in place identifying
the location of the washout area. Part of inspecting and maintaining washout areas is ensuring that
adequate signage is provided and in good repair and that the washout area is being used, as opposed to
washout in non-designated areas of the site.
Remove concrete waste in the washout area, as needed to maintain BMP function (typically when filled to
about two-thirds of its capacity). Collect concrete waste and deliver offsite to a designated disposal
location.
Upon termination of use of the washout site, accumulated solid waste, including concrete waste and any
contaminated soils, must be removed from the site to prevent on-site disposal of solid waste. If the wash
water is allowed to evaporate and the concrete hardens, it may be recycled.
Photograph CWA-3. Earthen concrete washout. Photo
courtesy of CDOT.
Photograph CWA-2. Prefabricated concrete washout. Photo
courtesy of CDOT.
Concrete Washout Area (CWA) MM-1
November 2010 Urban Drainage and Flood Control District CWA-3
Urban Storm Drainage Criteria Manual Volume 3
MM-1 Concrete Washout Area (CWA)
CWA-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Earth Dikes and Drainage Swales (ED/DS) EC-10
November 2010 Urban Drainage and Flood Control District ED/DS-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph ED/DS-1. Example of an earth dike used to divert
flows at a construction site. Photo courtesy of CDOT.
Description
Earth dikes and drainage swales are
temporary storm conveyance channels
constructed either to divert runoff around
slopes or to convey runoff to additional
sediment control BMPs prior to discharge
of runoff from a site. Drainage swales
may be lined or unlined, but if an unlined
swale is used, it must be well compacted
and capable of resisting erosive velocities.
Appropriate Uses
Earth dikes and drainage swales are
typically used to control the flow path of
runoff at a construction site by diverting
runoff around areas prone to erosion, such
as steep slopes. Earth dikes and drainage
swales may also be constructed as
temporary conveyance features. This will
direct runoff to additional sediment control
treatment BMPs, such as sediment traps or
basins.
Design and Installation
When earth dikes are used to divert water for slope protection, the earth dike typically consists of a
horizontal ridge of soil placed perpendicular to the slope and angled slightly to provide drainage along the
contour. The dike is used in conjunction with a swale or a small channel upslope of the berm to convey
the diverted water. Temporary diversion dikes can be constructed by excavation of a V-shaped trench or
ditch and placement of the fill on the downslope side of the cut. There are two types of placement for
temporary slope diversion dikes:
A dike located at the top of a slope to divert upland runoff away from the disturbed area and convey it
in a temporary or permanent channel.
A diversion dike located at the base or mid-slope of a disturbed area to intercept runoff and reduce the
effective slope length.
Depending on the project, either an earth dike or drainage swale may be more appropriate. If there is a
need for cut on the project, then an excavated drainage
swale may be better suited. When the project is primarily
fill, then a conveyance constructed using a berm may be the
better option.
All dikes or swales receiving runoff from a disturbed
area should direct stormwater to a sediment control
BMP such as a sediment trap or basin.
Earth Dikes and Drainage Swales
Functions
Erosion Control Yes
Sediment Control Moderate
Site/Material Management No
EC-10 Earth Dikes and Drainage Swales (ED/DS)
ED/DS-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Unlined dikes or swales should only be used for intercepting sheet flow runoff and are not intended
for diversion of concentrated flows.
Details with notes are provided for several design variations, including:
ED-1. Unlined Earth Dike formed by Berm
DS-1. Unlined Excavated Swale
DS-2. Unlined Swale Formed by Cut and Fill
DS-3. ECB-lined Swale
DS-4. Synthetic-lined Swale
DS-5. Riprap-lined Swale
The details also include guidance on permissible velocities for cohesive channels if unlined approaches
will be used.
Maintenance and Removal
Inspect earth dikes for stability, compaction, and signs of erosion and repair. Inspect side slopes for
erosion and damage to erosion control fabric. Stabilize slopes and repair fabric as necessary. If there is
reoccurring extensive damage, consider installing rock check dams or lining the channel with riprap.
If drainage swales are not permanent, remove dikes and fill channels when the upstream area is stabilized.
Stabilize the fill or disturbed area immediately following removal by revegetation or other permanent
stabilization method approved by the local jurisdiction.
Earth Dikes and Drainage Swales (ED/DS) EC-10
November 2010 Urban Drainage and Flood Control District ED/DS-3
Urban Storm Drainage Criteria Manual Volume 3
EC-10 Earth Dikes and Drainage Swales (ED/DS)
ED/DS-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Earth Dikes and Drainage Swales (ED/DS) EC-10
November 2010 Urban Drainage and Flood Control District ED/DS-5
Urban Storm Drainage Criteria Manual Volume 3
Good Housekeeping Practices (GH) MM-3
November 2010 Urban Drainage and Flood Control District GH-1
Urban Storm Drainage Criteria Manual Volume 3
Photographs GH-1 and GH-2. Proper materials
storage and secondary containment for fuel tanks
are important good housekeeping practices. Photos
courtesy of CDOT and City of Aurora.
Description
Implement construction site good housekeeping practices to
prevent pollution associated with solid, liquid and hazardous
construction-related materials and wastes. Stormwater
Management Plans (SWMPs) should clearly specify BMPs
including these good housekeeping practices:
Provide for waste management.
Establish proper building material staging areas.
Designate paint and concrete washout areas.
Establish proper equipment/vehicle fueling and
maintenance practices.
Control equipment/vehicle washing and allowable non-
stormwater discharges.
Develop a spill prevention and response plan.
Acknowledgement: This Fact Sheet is based directly on
EPA guidance provided in Developing Your Stormwater
Pollution Prevent Plan (EPA 2007).
Appropriate Uses
Good housekeeping practices are necessary at all construction sites.
Design and Installation
The following principles and actions should be addressed in SWMPs:
Provide for Waste Management. Implement management procedures and practices to prevent or
reduce the exposure and transport of pollutants in stormwater from solid, liquid and sanitary wastes
that will be generated at the site. Practices such as trash disposal, recycling, proper material handling,
and cleanup measures can reduce the potential for stormwater runoff to pick up construction site
wastes and discharge them to surface waters. Implement a comprehensive set of waste-management
practices for hazardous or toxic materials, such as paints, solvents, petroleum products, pesticides,
wood preservatives, acids, roofing tar, and other materials. Practices should include storage,
handling, inventory, and cleanup procedures, in case of spills. Specific practices that should be
considered include:
Solid or Construction Waste
o Designate trash and bulk waste-collection areas on-
site.
Good Housekeeping
Functions
Erosion Control No
Sediment Control No
Site/Material Management Yes
MM-3 Good Housekeeping Practices (GH)
GH-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Photograph GH-3. Locate portable toilet facilities on level
surfaces away from waterways and storm drains. Photo
courtesy of WWE.
o Recycle materials whenever possible (e.g., paper, wood, concrete, oil).
o Segregate and provide proper disposal options for hazardous material wastes.
o Clean up litter and debris from the construction site daily.
o Locate waste-collection areas away from streets, gutters, watercourses, and storm drains. Waste-
collection areas (dumpsters, and such) are often best located near construction site entrances to
minimize traffic on disturbed soils. Consider secondary containment around waste collection
areas to minimize the likelihood of contaminated discharges.
o Empty waste containers before they are full and overflowing.
Sanitary and Septic Waste
o Provide convenient, well-maintained, and properly located toilet facilities on-site.
o Locate toilet facilities away from storm drain inlets and waterways to prevent accidental spills
and contamination of stormwater.
o Maintain clean restroom facilities and empty portable toilets regularly.
o Where possible, provide secondary containment pans under portable toilets.
o Provide tie-downs or stake-downs for portable toilets.
o Educate employees, subcontractors, and suppliers on locations of facilities.
o Treat or dispose of sanitary and septic waste in accordance with state or local regulations. Do not
discharge or bury wastewater at the construction site.
o Inspect facilities for leaks. If found, repair or replace immediately.
o Special care is necessary during maintenance (pump out) to ensure that waste and/or biocide are
not spilled on the ground.
Hazardous Materials and Wastes
o Develop and implement employee and
subcontractor education, as needed, on
hazardous and toxic waste handling,
storage, disposal, and cleanup.
o Designate hazardous waste-collection
areas on-site.
o Place all hazardous and toxic material
wastes in secondary containment.
Good Housekeeping Practices (GH) MM-3
November 2010 Urban Drainage and Flood Control District GH-3
Urban Storm Drainage Criteria Manual Volume 3
o Hazardous waste containers should be inspected to ensure that all containers are labeled properly
and that no leaks are present.
Establish Proper Building Material Handling and Staging Areas. The SWMP should include
comprehensive handling and management procedures for building materials, especially those that are
hazardous or toxic. Paints, solvents, pesticides, fuels and oils, other hazardous materials or building
materials that have the potential to contaminate stormwater should be stored indoors or under cover
whenever possible or in areas with secondary containment. Secondary containment measures prevent
a spill from spreading across the site and may include dikes, berms, curbing, or other containment
methods. Secondary containment techniques should also ensure the protection of groundwater.
Designate staging areas for activities such as fueling vehicles, mixing paints, plaster, mortar, and
other potential pollutants. Designated staging areas enable easier monitoring of the use of materials
and clean up of spills. Training employees and subcontractors is essential to the success of this
pollution prevention principle. Consider the following specific materials handling and staging
practices:
o Train employees and subcontractors in proper handling and storage practices.
o Clearly designate site areas for staging and storage with signs and on construction drawings.
Staging areas should be located in areas central to the construction site. Segment the staging area
into sub-areas designated for vehicles, equipment, or stockpiles. Construction entrances and exits
should be clearly marked so that delivery vehicles enter/exit through stabilized areas with vehicle
tracking controls (See Vehicle Tracking Control Fact Sheet).
o Provide storage in accordance with Spill Protection, Control and Countermeasures (SPCC)
requirements and plans and provide cover and impermeable perimeter control, as necessary, for
hazardous materials and contaminated soils that must be stored on site.
o Ensure that storage containers are regularly inspected for leaks, corrosion, support or foundation
failure, or other signs of deterioration and tested for soundness.
o Reuse and recycle construction materials when possible.
Designate Concrete Washout Areas. Concrete contractors should be encouraged to use the washout
facilities at their own plants or dispatch facilities when feasible; however, concrete washout
commonly occurs on construction sites. If it is necessary to provide for concrete washout areas on-
site, designate specific washout areas and design facilities to handle anticipated washout water.
Washout areas should also be provided for paint and stucco operations. Because washout areas can
be a source of pollutants from leaks or spills, care must be taken with regard to their placement and
proper use. See the Concrete Washout Area Fact Sheet for detailed guidance.
Both self-constructed and prefabricated washout containers can fill up quickly when concrete, paint,
and stucco work are occurring on large portions of the site. Be sure to check for evidence that
contractors are using the washout areas and not dumping materials onto the ground or into drainage
facilities. If the washout areas are not being used regularly, consider posting additional signage,
relocating the facilities to more convenient locations, or providing training to workers and
contractors.
When concrete, paint, or stucco is part of the construction process, consider these practices which will
help prevent contamination of stormwater. Include the locations of these areas and the maintenance
and inspection procedures in the SWMP.
MM-3 Good Housekeeping Practices (GH)
GH-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
o Do not washout concrete trucks or equipment into storm drains, streets, gutters, uncontained
areas, or streams. Only use designated washout areas.
o Establish washout areas and advertise their locations with signs. Ensure that signage remains in
good repair.
o Provide adequate containment for the amount of wash water that will be used.
o Inspect washout structures daily to detect leaks or tears and to identify when materials need to be
removed.
o Dispose of materials properly. The preferred method is to allow the water to evaporate and to
recycle the hardened concrete. Full service companies may provide dewatering services and
should dispose of wastewater properly. Concrete wash water can be highly polluted. It should
not be discharged to any surface water, storm sewer system, or allowed to infiltrate into the
ground in the vicinity of waterbodies. Washwater should not be discharged to a sanitary sewer
system without first receiving written permission from the system operator.
Establish Proper Equipment/Vehicle Fueling and Maintenance Practices. Create a clearly
designated on-site fueling and maintenance area that is clean and dry. The on-site fueling area should
have a spill kit, and staff should know how to use it. If possible, conduct vehicle fueling and
maintenance activities in a covered area. Consider the following practices to help prevent the
discharge of pollutants to stormwater from equipment/vehicle fueling and maintenance. Include the
locations of designated fueling and maintenance areas and inspection and maintenance procedures in
the SWMP.
o Train employees and subcontractors in proper fueling procedures (stay with vehicles during
fueling, proper use of pumps, emergency shutoff valves, etc.).
o Inspect on-site vehicles and equipment regularly for leaks, equipment damage, and other service
problems.
o Clearly designate vehicle/equipment service areas away from drainage facilities and watercourses
to prevent stormwater run-on and runoff.
o Use drip pans, drip cloths, or absorbent pads when replacing spent fluids.
o Collect all spent fluids, store in appropriate labeled containers in the proper storage areas, and
recycle fluids whenever possible.
Control Equipment/Vehicle Washing and Allowable Non-Stormwater Discharges. Implement
practices to prevent contamination of surface and groundwater from equipment and vehicle wash
water. Representative practices include:
o Educate employees and subcontractors on proper washing procedures.
o Use off-site washing facilities, when available.
o Clearly mark the washing areas and inform workers that all washing must occur in this area.
o Contain wash water and treat it using BMPs. Infiltrate washwater when possible, but maintain
separation from drainage paths and waterbodies.
Good Housekeeping Practices (GH) MM-3
November 2010 Urban Drainage and Flood Control District GH-5
Urban Storm Drainage Criteria Manual Volume 3
o Use high-pressure water spray at vehicle washing facilities without detergents. Water alone can
remove most dirt adequately.
o Do not conduct other activities, such as vehicle repairs, in the wash area.
o Include the location of the washing facilities and the inspection and maintenance procedures in
the SWMP.
Develop a Spill Prevention and Response Plan. Spill prevention and response procedures must be
identified in the SWMP. Representative procedures include identifying ways to reduce the chance of
spills, stop the source of spills, contain and clean up spills, dispose of materials contaminated by
spills, and train personnel responsible for spill prevention and response. The plan should also specify
material handling procedures and storage requirements and ensure that clear and concise spill cleanup
procedures are provided and posted for areas in which spills may potentially occur. When developing
a spill prevention plan, include the following:
o Note the locations of chemical storage areas, storm drains, tributary drainage areas, surface
waterbodies on or near the site, and measures to stop spills from leaving the site.
o Provide proper handling and safety procedures for each type of waste. Keep Material Safety Data
Sheets (MSDSs) for chemical used on site with the SWMP.
o Establish an education program for employees and subcontractors on the potential hazards to
humans and the environment from spills and leaks.
o Specify how to notify appropriate authorities, such as police and fire departments, hospitals, or
municipal sewage treatment facilities to request assistance. Emergency procedures and contact
numbers should be provided in the SWMP and posted at storage locations.
o Describe the procedures, equipment and materials for immediate cleanup of spills and proper
disposal.
o Identify personnel responsible for implementing the plan in the event of a spill. Update the spill
prevention plan and clean up materials as changes occur to the types of chemicals stored and used
at the facility.
MM-3 Good Housekeeping Practices (GH)
GH-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Spill Prevention, Control, and Countermeasure (SPCC) Plan
Construction sites may be subject to 40 CFR Part 112 regulations that require the preparation and
implementation of a SPCC Plan to prevent oil spills from aboveground and underground storage tanks.
The facility is subject to this rule if it is a non-transportation-related facility that:
Has a total storage capacity greater than 1,320 gallons or a completely buried storage capacity
greater than 42,000 gallons.
Could reasonably be expected to discharge oil in quantities that may be harmful to navigable waters
of the United States and adjoining shorelines.
Furthermore, if the facility is subject to 40 CFR Part 112, the SWMP should reference the SPCC Plan.
To find out more about SPCC Plans, see EPA's website on SPPC at www.epa.gov/oilspill/spcc.htm.
Reporting Oil Spills
In the event of an oil spill, contact the National Response Center toll free at 1-800-424- 8802 for
assistance, or for more details, visit their website: www.nrc.uscg.mil.
Maintenance and Removal
Effective implementation of good housekeeping practices is dependent on clear designation of personnel
responsible for supervising and implementing good housekeeping programs, such as site cleanup and
disposal of trash and debris, hazardous material management and disposal, vehicle and equipment
maintenance, and other practices. Emergency response "drills" may aid in emergency preparedness.
Checklists may be helpful in good housekeeping efforts.
Staging and storage areas require permanent stabilization when the areas are no longer being used for
construction-related activities.
Construction-related materials, debris and waste must be removed from the construction site once
construction is complete.
Design Details
See the following Fact Sheets for related Design Details:
MM-1 Concrete Washout Area
MM-2 Stockpile Management
SM-4 Vehicle Tracking Control
Design details are not necessary for other good housekeeping practices; however, be sure to designate
where specific practices will occur on the appropriate construction drawings.
Rock Sock (RS) SC-5
November 2010 Urban Drainage and Flood Control District RS-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph RS-1. Rock socks placed at regular intervals in a curb
line can help reduce sediment loading to storm sewer inlets. Rock
socks can also be used as perimeter controls.
Description
A rock sock is constructed of gravel
that has been wrapped by wire mesh or
a geotextile to form an elongated
cylindrical filter. Rock socks are
typically used either as a perimeter
control or as part of inlet protection.
When placed at angles in the curb line,
rock socks are typically referred to as
curb socks. Rock socks are intended to
trap sediment from stormwater runoff
that flows onto roadways as a result of
construction activities.
Appropriate Uses
Rock socks can be used at the perimeter
of a disturbed area to control localized
sediment loading. A benefit of rock
socks as opposed to other perimeter controls is that they do not have to be trenched or staked into the
ground; therefore, they are often used on roadway construction projects where paved surfaces are present.
Use rock socks in inlet protection applications when the construction of a roadway is substantially
complete and the roadway has been directly connected to a receiving storm system.
Design and Installation
When rock socks are used as perimeter controls, the maximum recommended tributary drainage area per
100 lineal feet of rock socks is approximately 0.25 acres with disturbed slope length of up to 150 feet and
a tributary slope gradient no steeper than 3:1. A rock sock design detail and notes are provided in Detail
RS-1. Also see the Inlet Protection Fact Sheet for design and installation guidance when rock socks are
used for inlet protection and in the curb line.
When placed in the gutter adjacent to a curb, rock socks should protrude no more than two feet from the
curb in order for traffic to pass safely. If located in a high traffic area, place construction markers to alert
drivers and street maintenance workers of their presence.
Maintenance and Removal
Rock socks are susceptible to displacement and breaking due to vehicle traffic. Inspect rock socks for
damage and repair or replace as necessary. Remove sediment by sweeping or vacuuming as needed to
maintain the functionality of the BMP, typically when sediment
has accumulated behind the rock sock to one-half of the sock's
height.
Once upstream stabilization is complete, rock socks and
accumulated sediment should be removed and properly disposed.
Rock Sock
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management No
SC-5 Rock Sock (RS)
RS-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Rock Sock (RS) SC-5
November 2010 Urban Drainage and Flood Control District RS-3
Urban Storm Drainage Criteria Manual Volume 3
Sediment Control Log (SCL) SC-2
November 2015 Urban Drainage and Flood Control District SCL-1
Urban Storm Drainage Criteria Manual Volume 3
Photographs SCL-1 and SCL-2. Sediment control logs used as 1) a
perimeter control around a soil stockpile; and, 2) as a "J-hook"
perimeter control at the corner of a construction site.
Description
A sediment control log is a linear roll
made of natural materials such as
straw, coconut fiber, or compost. The
most common type of sediment control
log has straw filling and is often
referred to as a "straw wattle." All
sediment control logs are used as a
sediment barrier to intercept sheet flow
runoff from disturbed areas.
Appropriate Uses
Sediment control logs can be used in
the following applications to trap
sediment:
As perimeter control for stockpiles
and the site.
As part of inlet protection designs.
As check dams in small drainage
ditches. (Sediment control logs
are not intended for use in
channels with high flow
velocities.)
On disturbed slopes to shorten flow
lengths (as an erosion control).
As part of multi-layered perimeter control along a receiving water such as a stream, pond or wetland.
Sediment control logs work well in combination with other layers of erosion and sediment controls.
Design and Installation
Sediment control logs should be installed along the contour to avoid concentrating flows. The maximum
allowable tributary drainage area per 100 lineal feet of sediment control log, installed along the contour, is
approximately 0.25 acres with a disturbed slope length of up to 150 feet and a tributary slope gradient no
steeper than 3:1. Longer and steeper slopes require additional measures. This recommendation only
applies to sediment control logs installed along the contour. When installed for other uses, such as
perimeter control, it should be installed in a way that will not
produce concentrated flows. For example, a "J-hook"
installation may be appropriate to force runoff to pond and
evaporate or infiltrate in multiple areas rather than concentrate
and cause erosive conditions parallel to the BMP.
Sediment Control Log
Functions
Erosion Control Moderate
Sediment Control Yes
Site/Material Management No
SC-2 Sediment Control Log (SCL)
SCL-2 Urban Drainage and Flood Control District November 2015
Urban Storm Drainage Criteria Manual Volume 3
Although sediment control logs initially allow runoff to flow through the BMP, they can quickly become
a barrier and should be installed as if they are impermeable.
Design details and notes for sediment control logs are provided in the following details. Sediment logs
must be properly installed per the detail to prevent undercutting, bypassing and displacement. When
installed on slopes, sediment control logs should be installed along the contours (i.e., perpendicular to
flow).
Improper installation can lead to poor performance. Be sure that sediment control logs are properly
trenched (if lighter than 8 lb/foot), anchored and tightly jointed.
Maintenance and Removal
Be aware that sediment control logs will eventually degrade. Remove accumulated sediment before the
depth is one-half the height of the sediment log and repair damage to the sediment log, typically by
replacing the damaged section.
Once the upstream area is stabilized, remove and properly dispose of the logs. Areas disturbed beneath
the logs may need to be seeded and mulched. Sediment control logs that are biodegradable may
occasionally be left in place (e.g., when logs are used in conjunction with erosion control blankets as
permanent slope breaks). However, removal of sediment control logs after final stabilization is typically
appropriate when used in perimeter control, inlet protection and check dam applications. Compost from
compost sediment control logs may be spread over the area and seeded as long as this does not cover
newly established vegetation.
Sediment Control Log (SCL) SC-2
November 2015 Urban Drainage and Flood Control District SCL-3
Urban Storm Drainage Criteria Manual Volume 3
SC-2 Sediment Control Log (SCL)
SCL-4 Urban Drainage and Flood Control District November 2015
Urban Storm Drainage Criteria Manual Volume 3
Sediment Control Log (SCL) SC-2
November 2015 Urban Drainage and Flood Control District SCL-5
Urban Storm Drainage Criteria Manual Volume 3
SC-2 Sediment Control Log (SCL)
SCL-6 Urban Drainage and Flood Control District November 2015
Urban Storm Drainage Criteria Manual Volume 3
Silt Fence (SF) SC-1
November 2010 Urban Drainage and Flood Control District SF-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SF-1. Silt fence creates a sediment barrier, forcing
sheet flow runoff to evaporate or infiltrate.
Description
A silt fence is a woven geotextile fabric
attached to wooden posts and trenched
into the ground. It is designed as a
sediment barrier to intercept sheet flow
runoff from disturbed areas.
Appropriate Uses
A silt fence can be used where runoff is
conveyed from a disturbed area as sheet
flow. Silt fence is not designed to
receive concentrated flow or to be used
as a filter fabric. Typical uses include:
Down slope of a disturbed area to
accept sheet flow.
Along the perimeter of a receiving
water such as a stream, pond or
wetland.
At the perimeter of a construction site.
Design and Installation
Silt fence should be installed along the contour of slopes so that it intercepts sheet flow. The maximum
recommended tributary drainage area per 100 lineal feet of silt fence, installed along the contour, is
approximately 0.25 acres with a disturbed slope length of up to 150 feet and a tributary slope gradient no
steeper than 3:1. Longer and steeper slopes require additional measures. This recommendation only
applies to silt fence installed along the contour. Silt fence installed for other uses, such as perimeter
control, should be installed in a way that will not produce concentrated flows. For example, a "J-hook"
installation may be appropriate to force runoff to pond and evaporate or infiltrate in multiple areas rather
than concentrate and cause erosive conditions parallel to the silt fence.
See Detail SF-1 for proper silt fence installation, which involves proper trenching, staking, securing the
fabric to the stakes, and backfilling the silt fence. Properly installed silt fence should not be easily pulled
out by hand and there should be no gaps between the ground and the fabric.
Silt fence must meet the minimum allowable strength requirements, depth of installation requirement, and
other specifications in the design details. Improper installation
of silt fence is a common reason for silt fence failure; however,
when properly installed and used for the appropriate purposes, it
can be highly effective.
Silt Fence
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management No
SC-1 Silt Fence (SF)
SF-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Photograph SF-2. When silt fence is not installed along
the contour, a "J-hook" installation may be appropriate
to ensure that the BMP does not create concentrated
flow parallel to the silt fence. Photo courtesy of Tom
Gore.
Maintenance and Removal
Inspection of silt fence includes observing the
material for tears or holes and checking for slumping
fence and undercut areas bypassing flows. Repair of
silt fence typically involves replacing the damaged
section with a new section. Sediment accumulated
behind silt fence should be removed, as needed to
maintain BMP effectiveness, typically before it
reaches a depth of 6 inches.
Silt fence may be removed when the upstream area
has reached final stabilization.
Silt Fence (SF) SC-1
November 2010 Urban Drainage and Flood Control District SF-3
Urban Storm Drainage Criteria Manual Volume 3
SC-1 Silt Fence (SF)
SF-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Street Sweeping and Vacuuming (SS) SM-7
November 2010 Urban Drainage and Flood Control District SS-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SS-1. A street sweeper removes sediment and potential
pollutants along the curb line at a construction site. Photo courtesy of
Tom Gore.
Description
Street sweeping and vacuuming remove
sediment that has been tracked onto
roadways to reduce sediment transport
into storm drain systems or a surface
waterway.
Appropriate Uses
Use this practice at construction sites
where vehicles may track sediment
offsite onto paved roadways.
Design and Installation
Street sweeping or vacuuming should be
conducted when there is noticeable
sediment accumulation on roadways adjacent to the construction site. Typically, this will be concentrated
at the entrance/exit to the construction site. Well-maintained stabilized construction entrances, vehicle
tracking controls and tire wash facilities can help reduce the necessary frequency of street sweeping and
vacuuming.
On smaller construction sites, street sweeping can be conducted manually using a shovel and broom.
Never wash accumulated sediment on roadways into storm drains.
Maintenance and Removal
Inspect paved roads around the perimeter of the construction site on a daily basis and more
frequently, as needed. Remove accumulated sediment, as needed.
Following street sweeping, check inlet protection that may have been displaced during street
sweeping.
Inspect area to be swept for materials that may be hazardous prior to beginning sweeping operations.
Street Sweeping/ Vacuuming
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management Yes
Stabilized Staging Area (SSA) SM-6
November 2010 Urban Drainage and Flood Control District SSA-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SSA-1. Example of a staging area with a gravel surface to
prevent mud tracking and reduce runoff. Photo courtesy of Douglas
County.
Description
A stabilized staging area is a clearly
designated area where construction
equipment and vehicles, stockpiles, waste
bins, and other construction-related
materials are stored. The contractor
office trailer may also be located in this
area. Depending on the size of the
construction site, more than one staging
area may be necessary.
Appropriate Uses
Most construction sites will require a
staging area, which should be clearly
designated in SWMP drawings. The layout
of the staging area may vary depending on
the type of construction activity. Staging areas located in roadways due to space constraints require
special measures to avoid materials being washed into storm inlets.
Design and Installation
Stabilized staging areas should be completed prior to other construction activities beginning on the site.
Major components of a stabilized staging area include:
Appropriate space to contain storage and provide for loading/unloading operations, as well as parking
if necessary.
A stabilized surface, either paved or covered, with 3-inch diameter aggregate or larger.
Perimeter controls such as silt fence, sediment control logs, or other measures.
Construction fencing to prevent unauthorized access to construction materials.
Provisions for Good Housekeeping practices related to materials storage and disposal, as described in
the Good Housekeeping BMP Fact Sheet.
A stabilized construction entrance/exit, as described in the Vehicle Tracking Control BMP Fact Sheet,
to accommodate traffic associated with material delivery and waste disposal vehicles.
Over-sizing the stabilized staging area may result in disturbance of existing vegetation in excess of that
required for the project. This increases costs, as well as
requirements for long-term stabilization following the
construction period. When designing the stabilized staging area,
minimize the area of disturbance to the extent practical.
Stabilized Staging Area
Functions
Erosion Control Yes
Sediment Control Moderate
Site/Material
Yes
SM-6 Stabilized Staging Area (SSA)
SSA-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
See Detail SSA-1 for a typical stabilized staging area and SSA-2 for a stabilized staging area when
materials staging in roadways is required.
Maintenance and Removal
Maintenance of stabilized staging areas includes maintaining a stable surface cover of gravel, repairing
perimeter controls, and following good housekeeping practices.
When construction is complete, debris, unused stockpiles and materials should be recycled or properly
disposed. In some cases, this will require disposal of contaminated soil from equipment leaks in an
appropriate landfill. Staging areas should then be permanently stabilized with vegetation or other surface
cover planned for the development.
Minimizing Long-Term Stabilization Requirements
Utilize off-site parking and restrict vehicle access to the site.
Use construction mats in lieu of rock when staging is provided in an area that will not be disturbed
otherwise.
Consider use of a bermed contained area for materials and equipment that do not require a
stabilized surface.
Consider phasing of staging areas to avoid disturbance in an area that will not be otherwise
disturbed.
Stabilized Staging Area (SSA) SM-6
November 2010 Urban Drainage and Flood Control District SSA-3
Urban Storm Drainage Criteria Manual Volume 3
SM-6 Stabilized Staging Area (SSA)
SSA-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Temporary and Permanent Seeding (TS/PS) EC-2
June 2012 Urban Drainage and Flood Control District TS/PS-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph TS/PS -1. Equipment used to drill seed. Photo courtesy of
Douglas County.
Description
Temporary seeding can be used to
stabilize disturbed areas that will be
inactive for an extended period.
Permanent seeding should be used to
stabilize areas at final grade that will not
be otherwise stabilized. Effective seeding
includes preparation of a seedbed,
selection of an appropriate seed mixture,
proper planting techniques, and protection
of the seeded area with mulch, geotextiles,
or other appropriate measures.
Appropriate Uses
When the soil surface is disturbed and
will remain inactive for an extended
period (typically 30 days or longer),
proactive stabilization measures should be implemented. If the inactive period is short-lived (on the order
of two weeks), techniques such as surface roughening may be appropriate. For longer periods of
inactivity, temporary seeding and mulching can provide effective erosion control. Permanent seeding
should be used on finished areas that have not been otherwise stabilized.
Typically, local governments have their own seed mixes and timelines for seeding. Check jurisdictional
requirements for seeding and temporary stabilization.
Design and Installation
Effective seeding requires proper seedbed preparation, selection of an appropriate seed mixture, use of
appropriate seeding equipment to ensure proper coverage and density, and protection with mulch or fabric
until plants are established.
The USDCM Volume 2 Revegetation Chapter contains detailed seed mix, soil preparations, and seeding
and mulching recommendations that may be referenced to supplement this Fact Sheet.
Drill seeding is the preferred seeding method. Hydroseeding is not recommended except in areas where
steep slopes prevent use of drill seeding equipment, and even in these instances it is preferable to hand
seed and mulch. Some jurisdictions do not allow hydroseeding or hydromulching.
Seedbed Preparation
Prior to seeding, ensure that areas to be revegetated have
soil conditions capable of supporting vegetation. Overlot
grading can result in loss of topsoil, resulting in poor quality
subsoils at the ground surface that have low nutrient value,
little organic matter content, few soil microorganisms,
rooting restrictions, and conditions less conducive to
infiltration of precipitation. As a result, it is typically
necessary to provide stockpiled topsoil, compost, or other
Temporary and Permanent Seeding
Functions
Erosion Control Yes
Sediment Control No
Site/Material Management No
EC-2 Temporary and Permanent Seeding (TS/PS)
TS/PS-2 Urban Drainage and Flood Control District June 2012
Urban Storm Drainage Criteria Manual Volume 3
soil amendments and rototill them into the soil to a depth of 6 inches or more.
Topsoil should be salvaged during grading operations for use and spread on areas to be revegetated later.
Topsoil should be viewed as an important resource to be utilized for vegetation establishment, due to its
water-holding capacity, structure, texture, organic matter content, biological activity, and nutrient content.
The rooting depth of most native grasses in the semi-arid Denver metropolitan area is 6 to 18 inches. At a
minimum, the upper 6 inches of topsoil should be stripped, stockpiled, and ultimately respread across
areas that will be revegetated.
Where topsoil is not available, subsoils should be amended to provide an appropriate plant-growth
medium. Organic matter, such as well digested compost, can be added to improve soil characteristics
conducive to plant growth. Other treatments can be used to adjust soil pH conditions when needed. Soil
testing, which is typically inexpensive, should be completed to determine and optimize the types and
amounts of amendments that are required.
If the disturbed ground surface is compacted, rip or rototill the surface prior to placing topsoil. If adding
compost to the existing soil surface, rototilling is necessary. Surface roughening will assist in placement
of a stable topsoil layer on steeper slopes, and allow infiltration and root penetration to greater depth.
Prior to seeding, the soil surface should be rough and the seedbed should be firm, but neither too loose
nor compacted. The upper layer of soil should be in a condition suitable for seeding at the proper depth
and conducive to plant growth. Seed-to-soil contact is the key to good germination.
Seed Mix for Temporary Vegetation
To provide temporary vegetative cover on disturbed areas which will not be paved, built upon, or fully
landscaped or worked for an extended period (typically 30 days or more), plant an annual grass
appropriate for the time of planting and mulch the planted areas. Annual grasses suitable for the Denver
metropolitan area are listed in Table TS/PS-1. These are to be considered only as general
recommendations when specific design guidance for a particular site is not available. Local governments
typically specify seed mixes appropriate for their jurisdiction.
Seed Mix for Permanent Revegetation
To provide vegetative cover on disturbed areas that have reached final grade, a perennial grass mix should
be established. Permanent seeding should be performed promptly (typically within 14 days) after
reaching final grade. Each site will have different characteristics and a landscape professional or the local
jurisdiction should be contacted to determine the most suitable seed mix for a specific site. In lieu of a
specific recommendation, one of the perennial grass mixes appropriate for site conditions and growth
season listed in Table TS/PS-2 can be used. The pure live seed (PLS) rates of application recommended
in these tables are considered to be absolute minimum rates for seed applied using proper drill-seeding
equipment.
If desired for wildlife habitat or landscape diversity, shrubs such as rubber rabbitbrush (Chrysothamnus
nauseosus), fourwing saltbush (Atriplex canescens) and skunkbrush sumac (Rhus trilobata) could be
added to the upland seedmixes at 0.25, 0.5 and 1 pound PLS/acre, respectively. In riparian zones,
planting root stock of such species as American plum (Prunus americana), woods rose (Rosa woodsii),
plains cottonwood (Populus sargentii), and willow (Populus spp.) may be considered. On non-topsoiled
upland sites, a legume such as Ladak alfalfa at 1 pound PLS/acre can be included as a source of nitrogen
for perennial grasses.
Temporary and Permanent Seeding (TS/PS) EC-2
June 2012 Urban Drainage and Flood Control District TS/PS-3
Urban Storm Drainage Criteria Manual Volume 3
Seeding dates for the highest success probability of perennial species along the Front Range are generally
in the spring from April through early May and in the fall after the first of September until the ground
freezes. If the area is irrigated, seeding may occur in summer months, as well. See Table TS/PS-3 for
appropriate seeding dates.
Table TS/PS-1. Minimum Drill Seeding Rates for Various Temporary Annual Grasses
Speciesa
(Common name)
Growth
Seasonb
Pounds of
Pure Live Seed
(PLS)/acrec
Planting
Depth
(inches)
1. Oats Cool 35 - 50 1 - 2
2. Spring wheat Cool 25 - 35 1 - 2
3. Spring barley Cool 25 - 35 1 - 2
4. Annual ryegrass Cool 10 - 15 ½
5. Millet Warm 3 - 15 ½ - ¾
6. Sudangrass Warm 5–10 ½ - ¾
7. Sorghum Warm 5–10 ½ - ¾
8. Winter wheat Cool 20–35 1 - 2
9. Winter barley Cool 20–35 1 - 2
10. Winter rye Cool 20–35 1 - 2
11. Triticale Cool 25–40 1 - 2
a Successful seeding of annual grass resulting in adequate plant growth will
usually produce enough dead-plant residue to provide protection from
wind and water erosion for an additional year. This assumes that the cover
is not disturbed or mowed closer than 8 inches.
Hydraulic seeding may be substituted for drilling only where slopes are
steeper than 3:1 or where access limitations exist. When hydraulic
seeding is used, hydraulic mulching should be applied as a separate
operation, when practical, to prevent the seeds from being encapsulated in
the mulch.
b See Table TS/PS-3 for seeding dates. Irrigation, if consistently applied,
may extend the use of cool season species during the summer months.
c Seeding rates should be doubled if seed is broadcast, or increased by 50
percent if done using a Brillion Drill or by hydraulic seeding.
EC-2 Temporary and Permanent Seeding (TS/PS)
TS/PS-4 Urban Drainage and Flood Control District June 2012
Urban Storm Drainage Criteria Manual Volume 3
Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses
Commona
Name
Botanical
Name
Growth
Seasonb
Growth
Form
Seeds/
Pound
Pounds of
PLS/acre
Alakali Soil Seed Mix
Alkali sacaton Sporobolus airoides Cool Bunch 1,750,000 0.25
Basin wildrye Elymus cinereus Cool Bunch 165,000 2.5
Sodar streambank wheatgrass Agropyron riparium 'Sodar' Cool Sod 170,000 2.5
Jose tall wheatgrass Agropyron elongatum 'Jose' Cool Bunch 79,000 7.0
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5
Total 17.75
Fertile Loamy Soil Seed Mix
Ephriam crested wheatgrass Agropyron cristatum
'Ephriam' Cool Sod 175,000 2.0
Dural hard fescue Festuca ovina 'duriuscula' Cool Bunch 565,000 1.0
Lincoln smooth brome Bromus inermis leyss
'Lincoln' Cool Sod 130,000 3.0
Sodar streambank wheatgrass Agropyron riparium 'Sodar' Cool Sod 170,000 2.5
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 7.0
Total 15.5
High Water Table Soil Seed Mix
Meadow foxtail Alopecurus pratensis Cool Sod 900,000 0.5
Redtop Agrostis alba Warm Open sod 5,000,000 0.25
Reed canarygrass Phalaris arundinacea Cool Sod 68,000 0.5
Lincoln smooth brome Bromus inermis leyss
'Lincoln' Cool Sod 130,000 3.0
Pathfinder switchgrass Panicum virgatum
'Pathfinder' Warm Sod 389,000 1.0
Alkar tall wheatgrass Agropyron elongatum
'Alkar' Cool Bunch 79,000 5.5
Total 10.75
Transition Turf Seed Mixc
Ruebens Canadian bluegrass Poa compressa 'Ruebens' Cool Sod 2,500,000 0.5
Dural hard fescue Festuca ovina 'duriuscula' Cool Bunch 565,000 1.0
Citation perennial ryegrass Lolium perenne 'Citation' Cool Sod 247,000 3.0
Lincoln smooth brome Bromus inermis leyss
'Lincoln' Cool Sod 130,000 3.0
Total 7.5
Temporary and Permanent Seeding (TS/PS) EC-2
June 2012 Urban Drainage and Flood Control District TS/PS-5
Urban Storm Drainage Criteria Manual Volume 3
Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses (cont.)
Common
Name
Botanical
Name
Growth
Seasonb
Growth
Form
Seeds/
Pound
Pounds of
PLS/acre
Sandy Soil Seed Mix
Blue grama Bouteloua gracilis Warm Sod-forming
bunchgrass 825,000 0.5
Camper little bluestem Schizachyrium scoparium
'Camper' Warm Bunch 240,000 1.0
Prairie sandreed Calamovilfa longifolia Warm Open sod 274,000 1.0
Sand dropseed Sporobolus cryptandrus Cool Bunch 5,298,000 0.25
Vaughn sideoats grama Bouteloua curtipendula
'Vaughn' Warm Sod 191,000 2.0
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5
Total 10.25
Heavy Clay, Rocky Foothill Seed Mix
Ephriam crested wheatgrassd Agropyron cristatum
'Ephriam' Cool Sod 175,000 1.5
Oahe Intermediate wheatgrass Agropyron intermedium
'Oahe' Cool Sod 115,000 5.5
Vaughn sideoats gramae Bouteloua curtipendula
'Vaughn' Warm Sod 191,000 2.0
Lincoln smooth brome Bromus inermis leyss
'Lincoln' Cool Sod 130,000 3.0
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5
Total 17.5
a All of the above seeding mixes and rates are based on drill seeding followed by crimped straw mulch. These rates should be
doubled if seed is broadcast and should be increased by 50 percent if the seeding is done using a Brillion Drill or is applied
through hydraulic seeding. Hydraulic seeding may be substituted for drilling only where slopes are steeper than 3:1. If
hydraulic seeding is used, hydraulic mulching should be done as a separate operation.
b See Table TS/PS-3 for seeding dates.
c If site is to be irrigated, the transition turf seed rates should be doubled.
d Crested wheatgrass should not be used on slopes steeper than 6H to 1V.
e Can substitute 0.5 lbs PLS of blue grama for the 2.0 lbs PLS of Vaughn sideoats grama.
EC-2 Temporary and Permanent Seeding (TS/PS)
TS/PS-6 Urban Drainage and Flood Control District June 2012
Urban Storm Drainage Criteria Manual Volume 3
Table TS/PS-3. Seeding Dates for Annual and Perennial Grasses
Annual Grasses
(Numbers in table reference
species in Table TS/PS-1)
Perennial Grasses
Seeding Dates Warm Cool Warm Cool
January 1–March 15
March 16–April 30 4 1,2,3
May 1–May 15 4
May 16–June 30 4,5,6,7
July 1–July 15 5,6,7
July 16–August 31
September 1–September 30 8,9,10,11
October 1–December 31
Mulch
Cover seeded areas with mulch or an appropriate rolled erosion control product to promote establishment
of vegetation. Anchor mulch by crimping, netting or use of a non-toxic tackifier. See the Mulching BMP
Fact Sheet for additional guidance.
Maintenance and Removal
Monitor and observe seeded areas to identify areas of poor growth or areas that fail to germinate. Reseed
and mulch these areas, as needed.
An area that has been permanently seeded should have a good stand of vegetation within one growing
season if irrigated and within three growing seasons without irrigation in Colorado. Reseed portions of
the site that fail to germinate or remain bare after the first growing season.
Seeded areas may require irrigation, particularly during extended dry periods. Targeted weed control may
also be necessary.
Protect seeded areas from construction equipment and vehicle access.
Vehicle Tracking Control (VTC) SM-4
November 2010 Urban Drainage and Flood Control District VTC-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph VTC-1. A vehicle tracking control pad constructed with
properly sized rock reduces off-site sediment tracking.
Description
Vehicle tracking controls provide
stabilized construction site access where
vehicles exit the site onto paved public
roads. An effective vehicle tracking
control helps remove sediment (mud or
dirt) from vehicles, reducing tracking onto
the paved surface.
Appropriate Uses
Implement a stabilized construction
entrance or vehicle tracking control where
frequent heavy vehicle traffic exits the
construction site onto a paved roadway. An
effective vehicle tracking control is
particularly important during the following conditions:
Wet weather periods when mud is easily tracked off site.
During dry weather periods where dust is a concern.
When poorly drained, clayey soils are present on site.
Although wheel washes are not required in designs of vehicle tracking controls, they may be needed at
particularly muddy sites.
Design and Installation
Construct the vehicle tracking control on a level surface. Where feasible, grade the tracking control
towards the construction site to reduce off-site runoff. Place signage, as needed, to direct construction
vehicles to the designated exit through the vehicle tracking control. There are several different types of
stabilized construction entrances including:
VTC-1. Aggregate Vehicle Tracking Control. This is a coarse-aggregate surfaced pad underlain by a
geotextile. This is the most common vehicle tracking control, and when properly maintained can be
effective at removing sediment from vehicle tires.
VTC-2. Vehicle Tracking Control with Construction Mat or Turf Reinforcement Mat. This type of
control may be appropriate for site access at very small construction sites with low traffic volume over
vegetated areas. Although this application does not typically remove sediment from vehicles, it helps
protect existing vegetation and provides a stabilized entrance.
Vehicle Tracking Control
Functions
Erosion Control Moderate
Sediment Control Yes
Site/Material Management Yes
SM-4 Vehicle Tracking Control (VTC)
VTC-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Photograph VTC-2. A vehicle tracking control pad with wheel wash
facility. Photo courtesy of Tom Gore.
VTC-3. Stabilized Construction Entrance/Exit with Wheel Wash. This is an aggregate pad, similar
to VTC-1, but includes equipment for tire washing. The wheel wash equipment may be as simple as
hand-held power washing equipment to more advance proprietary systems. When a wheel wash is
provided, it is important to direct wash water to a sediment trap prior to discharge from the site.
Vehicle tracking controls are sometimes installed in combination with a sediment trap to treat runoff.
Maintenance and Removal
Inspect the area for degradation and
replace aggregate or material used for a
stabilized entrance/exit as needed. If the
area becomes clogged and ponds water,
remove and dispose of excess sediment
or replace material with a fresh layer of
aggregate as necessary.
With aggregate vehicle tracking controls,
ensure rock and debris from this area do
not enter the public right-of-way.
Remove sediment that is tracked onto the
public right of way daily or more
frequently as needed. Excess sediment
in the roadway indicates that the
stabilized construction entrance needs
maintenance.
Ensure that drainage ditches at the
entrance/exit area remain clear.
A stabilized entrance should be removed only when there is no longer the potential for vehicle tracking to
occur. This is typically after the site has been stabilized.
When wheel wash equipment is used, be sure that the wash water is discharged to a sediment trap prior to
discharge. Also inspect channels conveying the water from the wash area to the sediment trap and
stabilize areas that may be eroding.
When a construction entrance/exit is removed, excess sediment from the aggregate should be removed
and disposed of appropriately. The entrance should be promptly stabilized with a permanent surface
following removal, typically by paving.
Vehicle Tracking Control (VTC) SM-4
November 2010 Urban Drainage and Flood Control District VTC-3
Urban Storm Drainage Criteria Manual Volume 3
SM-4 Vehicle Tracking Control (VTC)
VTC-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Vehicle Tracking Control (VTC) SM-4
November 2010 Urban Drainage and Flood Control District VTC-5
Urban Storm Drainage Criteria Manual Volume 3
SM-4 Vehicle Tracking Control (VTC)
VTC-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Sediment Trap (ST) SC-8
November 2010 Urban Drainage and Flood Control District ST-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph ST-1. Sediment traps are used to collect sediment-laden
runoff from disturbed area. Photo courtesy of EPA Menu of BMPs.
Description
Sediment traps are formed by excavating
an area or by placing an earthen
embankment across a low area or
drainage swale. Sediment traps are
designed to capture drainage from
disturbed areas less than one acre and
allow settling of sediment.
Appropriate Uses
Sediment traps can be used in
combination with other layers of erosion
and sediment controls to trap sediment
from small drainage areas (less than one
acre) or areas with localized high sediment loading. For example, sediment traps are often provided in
conjunction with vehicle tracking controls and wheel wash facilities.
Design and Installation
A sediment trap consists of a small excavated basin with an earthen berm and a riprap outlet. The berm
of the sediment trap may be constructed from the excavated material and must be compacted to
95 percent of the maximum density in accordance with ASTM D698. An overflow outlet must be
provided at an elevation at least 6 inches below the top of the berm. See Detail ST-1 for additional design
and installation information.
Maintenance and Removal
Inspect the sediment trap embankments for stability and seepage.
Remove accumulated sediment as needed to maintain the effectiveness of the sediment trap, typically
when the sediment depth is approximately one-half the height of the outflow embankment.
Inspect the outlet for debris and damage. Repair damage to the outlet, and remove all obstructions.
A sediment trap should not be removed until the upstream area is sufficiently stabilized. Upon removal of
the trap, the disturbed area should be covered with topsoil and stabilized.
Sediment Trap
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management No
SC-8 Sediment Trap (ST)
ST-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Sediment Trap (ST) SC-8
November 2010 Urban Drainage and Flood Control District ST-3
Urban Storm Drainage Criteria Manual Volume 3
APPENDIX 2
BMP COST/ESCROW CALCULATIONS
Project:Disturbed Acres:1.92
EROSION CONTROL BMPs Units
Estimated
Quantity
Unit
Price
Total
Price
L.F. 590 $2.50 $1,475.00
EA. 4 $20.00 $80.00
EA. 1 $100.00 $100.00
EA. 1 $1,000.00 $1,000.00
EA. 2 $10.00 $20.00
L.F. 1060 $2.00 $2,120.00
EA. 2 $500.00 $1,000.00
L.F. 364 $1.60 $582.40
Sub-Total: $6,377.40
1.5 x Sub-Total: $9,566.10
Amount of security: $9,566.10
Total Acres x Price/acre: $2,880.00
$1,500.00 Sub-Total: $2,880.00
1.5 x Sub-Total: $4,320.00
Amount to Re-seed: $4,320.00
Minimum escrow amount: $3,000.00
Erosion Control Escrow:$9,566.10
Fields in yellow should be amended for this project.
Example Erosion and Sediment Control Escrow/Security
Calculation for The City of Fort Collins
BMP Amount
Silt Fence (SF)
Vehicle Tracking Control (VTC)
Curb Socks (CS)
Reseeding Amount
Construction Fence (CF)
Sediment Trap (ST)
Diversion Ditch (DD)
Miniumum Escrow Amount
Uplift Storage at Rudolph Farm Phase 1
Unit Price of Seeding per acre:
“The amount of the security must be based on one and one-half times the estimate of the cost to install the approved measures, or one and one-half times
the cost to re-vegetate the disturbed land to dry land grasses based upon unit cost determined by the City's Annual Revegetation and Stabilization Bid,
whichever is greater. In no instance, will the amount of security be less than one thousand five hundred dollars ($1,500) for residential development or three
thousand dollars ($3,000) for commercial development”
Inlet Protection (IP)
Concrete Washout (CW)
(add all other BMPs for the site in this list)
Final Escrow Amount
5/5/2025 9:11 AM D:\Projects\2207 PSS\Doc\Reports\SWMP\EC_Escrow_Phase 1.xls
Project:Disturbed Acres:1.00
EROSION CONTROL BMPs Units
Estimated
Quantity
Unit
Price
Total
Price
L.F. 630 $2.50 $1,575.00
EA. 1 $20.00 $20.00
EA. 1 $100.00 $100.00
EA. 2 $1,000.00 $2,000.00
Sub-Total: $3,695.00
1.5 x Sub-Total: $5,542.50
Amount of security: $5,542.50
Total Acres x Price/acre: $1,500.00
$1,500.00 Sub-Total: $1,500.00
1.5 x Sub-Total: $2,250.00
Amount to Re-seed: $2,250.00
Minimum escrow amount: $3,000.00
Erosion Control Escrow:$5,542.50
Fields in yellow should be amended for this project.
Example Erosion and Sediment Control Escrow/Security
Calculation for The City of Fort Collins
BMP Amount
Silt Fence (SF)
Vehicle Tracking Control (VTC)
Reseeding Amount
Miniumum Escrow Amount
Uplift Storage at Rudolph Farm Phase 2
Unit Price of Seeding per acre:
“The amount of the security must be based on one and one-half times the estimate of the cost to install the approved measures, or one and one-half times
the cost to re-vegetate the disturbed land to dry land grasses based upon unit cost determined by the City's Annual Revegetation and Stabilization Bid,
whichever is greater. In no instance, will the amount of security be less than one thousand five hundred dollars ($1,500) for residential development or three
thousand dollars ($3,000) for commercial development”
Inlet Protection (IP)
Concrete Washout (CW)
(add all other BMPs for the site in this list)
Final Escrow Amount
5/5/2025 9:13 AM D:\Projects\2207 PSS\Doc\Reports\SWMP\EC_Escrow_Phase 2.xls
APPENDIX 3
SOILS REPORT
GEOTECHNICAL ENGINEERING REPORT
PROSPECT SELF STORAGE PHASE 1
LOT 11 – RUDOLPH FARM
FORT COLLINS, COLORADO
EEC PROJECT NO. 1252011
Prepared for:
Uplift Development Group
2120 Midpoint Drive
Fort Collins, Colorado 80525
Attn: Mr. Tony Ollila (tony@upliftdg.com)
Prepared by:
Earth Engineering Consultants, LLC
4396 Greenfield Drive
Windsor, Colorado 80550
4396 Greenfield Drive
Windsor , C olorado 80 550
(970) 663-0282 FAX (970) 663-0282
www.earth -engineering.com
March 28, 2025
Revised April 4, 20251
Uplift Development Group
2120 Midpoint Drive
Fort Collins, Colorado 80525
Attn: Mr. Tony Ollila (tony@upliftdg.com)
Re: Geotechnical Engineering Report
Prospect Self Storage Phase 1
Lot 11 – Rudolph Farm
Fort Collins, Colorado
EEC Project No. 1252011
Mr. Ollila:
Enclosed are the results of the subsurface exploration completed by Earth Engineering
Consultants, LLC (EEC) for the referenced project. For this exploration, five (5) soil borings
were extended to depths of approximately 20 to 25½ feet below existing site grade. This
subsurface exploration was carried out in general accordance with our proposal dated February
20, 2025.
In summary, the subsurface conditions encountered in the test borings generally consisted of a
thin layer of vegetation and topsoil overlying approximately 3 to 7 feet of sandy lean clay
underlain by clayey, silty sand to the depths explored. No bedrock was encountered during the
exploration. Groundwater was measured at depths 5½ to 7 feet in the borings. The near surface
soils were slightly compressive to highly expansive and some of the soils were soft and expected
to have low support capacity.
Based on the subsurface conditions encountered, it is our opinion the proposed structure could be
supported on spread footing foundations bearing on minimum of 2 feet of imported structural fill
material placed upon over-excavated, moisture conditioned and recompacted existing soil.
Pavements and exterior flatwork should be supported on over-excavated, properly moisture
conditioned and recompacted soils. Geotechnical recommendations concerning design and
construction of the proposed building, floor slabs, flatwork and pavements are provided within
the attached report.
TABLE OF CONTENTS
INTRODUCTION......................................................................................................................... 1
PREVIOUS EXPLORATIONS ................................................................................................... 1
EXPLORATION AND TESTING PROCEDURES .................................................................. 1
EXISTING SITE CONDITIONS ................................................................................................ 2
SUBSURFACE CONDITIONS ................................................................................................... 3
Groundwater ............................................................................................................................... 4
SWELL-CONSOLIDATION TEST RESULTS ........................................................................ 4
ANALYSIS AND RECOMMENDATIONS ............................................................................... 5
Site Preparation ........................................................................................................................... 6
Foundations ................................................................................................................................. 7
Foundation and Utility Backfill .................................................................................................. 8
Floor Slabs and Exterior Flatwork .............................................................................................. 8
Lateral Earth Pressures ............................................................................................................... 9
Water Soluble Sulfates (SO4) .................................................................................................... 10
Seismic ...................................................................................................................................... 10
Pavement ................................................................................................................................... 10
Other Considerations ................................................................................................................ 11
GENERAL COMMENTS .......................................................................................................... 12
APPENDIX A — SITE PHOTOGRAPHS AND BORING LOCATION DIAGRAM
APPENDIX B — GENERAL NOTES, EXPLORATORY BORING LOGS AND FENCE
LOGS
APPENDIX C — LABORATORY TEST RESULTS
GEOTECHNICAL ENGINEERING REPORT
PROSPECT SELF STORAGE PHASE 1
LOT 11 – RUDOLPH FARM
FORT COLLINS, COLORADO
EEC PROJECT NO. 1252011
March 28, 2025
Revised April 4, 2025
INTRODUCTION
The geotechnical subsurface exploration for the proposed 3-story self-storage building in Fort
Collins, Colorado has been completed. The purpose of this report is to describe the subsurface
conditions encountered in the test borings, analyze and evaluate the field and laboratory test data and
provide geotechnical recommendations concerning design and construction of foundations, floors
and pavements. This scope of services was completed in general accordance with our proposal dated
February 20, 2025.
We understand the proposed project involves construction of Building A which is an approximately
34,000 square-foot, in plan line dimensions, 3-story building including paved parking and access
drives, planned for design and construction east of the Interstate 25 and north of East Prospect Road
in Fort Collins. The structure is expected to be a wood and/or steel-framed building, with stucco and
metal exterior, constructed with a slab-on-grade (no basement) main floor system. Foundation loads
for the planned building are assumed to be light to moderate with continuous wall loading less than 3
kips per foot and individual column loads less than 100 kips. Floor loads are expected to be
relatively with up to 200 psf. We understand that vehicle traffic on the site will likely be light duty to
medium duty vehicles with some heavy truck traffic. We understand that the building pad grade is
expected to be raised with up to 4½ feet of imported material.
PREVIOUS EXPLORATIONS
Earth Engineering Consultants, LLC performed a Preliminary Subsurface Exploration for the greater
Rudolph Farms development under EEC Project No. 1052027, report dated April 11, 2005, and a
Supplemental Preliminary Subsurface Exploration, report dated June 3, 2022 under EEC Project No.
1222014. Data from these reports were considered in preparation of this report.
EXPLORATION AND TESTING PROCEDURES
The building footprint was field located by others and the test boring locations were selected by
Earth Engineering Consultants, LLC (EEC) personnel. Approximate locations of the borings are
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 2
shown on the attached Boring Location Diagram. The test borings were advanced using a truck
mounted, CME-55 drill rig equipped with a hydraulic head employed in drilling and sampling
operations. The boreholes were advanced using 4-inch nominal diameter continuous flight solid
stem augers. Samples of the subsurface materials encountered in the borings were obtained using
split-barrel and California barrel sampling procedures in general accordance with ASTM
Specifications D1586 and D3550, respectively.
In the split-barrel and California barrel sampling procedures, standard sampling spoons are driven
into the ground by means of a 140-pound hammer falling a distance of 30 inches. The number of
blows required to drive the split-barrel and California barrel samplers is recorded and is used to
estimate the in-situ relative density of cohesionless soils and, to a lesser degree of accuracy, the
consistency of cohesive soils. In the California barrel sampling procedure, relatively intact samples
are obtained in removable brass liners. All samples obtained in the field were sealed and returned to
our laboratory for further examination, classification and testing.
Laboratory tests were conducted on select samples recovered from the borings with unconfined
compressive strength of appropriate samples estimated using a calibrated hand penetrometer.
Moisture content, dry density, Atterberg limits and washed sieve analysis tests were performed to
evaluate engineering characteristics and to determine the plasticity and quantity of fines in the
subgrades. Swell/consolidation tests evaluated the potential for volume changes due to moisture
variations and loading. Water-soluble sulfate content was measured in near-surface samples to assess
the risk of sulfate attack on concrete. The results of these tests are summarized in the attached boring
logs and summary sheets in the Appendices.
Samples were examined in the laboratory by a geotechnical engineer and classified in general
accordance with the Unified Soil Classification System as presented in the attached General Notes,
based on their texture and plasticity. The estimated group symbols are indicated on the boring logs
included in this report.
EXISTING SITE CONDITIONS
This 3.1-acre parcel is part of the larger proposed multi-use development known as Rudolph Farms.
The site is located approximately 850 feet north of East Prospect Road and east of Interstate 25 in
southeast Fort Collins, Colorado. Historically, the land has been used as agricultural cropland.
The Timnath Middle-High School facility lies to the east, while vacant land surrounds the site to the
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 3
north, south, and west. The terrain is relatively flat with about 3 feet of elevation change between
borings. Ground cover consisted of native weeds and grasses. The Timnath Reservoir Inlet Canal
forms the southern boundary of the site. Site photos taken during our drilling operations are included
in Appendix A. Below is an aerial image highlighting the proposed development area and its
surroundings.
Image 1: Google Earth Image (October 2024)
SUBSURFACE CONDITIONS
To develop subsurface information for the project, five (5) soil borings were advanced within the
proposed Building A footprint to depths of approximately 20 to 25½ feet below existing site grades.
EEC field personnel were on site during drilling to evaluate the subsurface conditions encountered
and direct the drilling activities. Field logs prepared by EEC site personnel were based on visual and
tactual observation of disturbed samples and auger cuttings. The final boring logs included with this
report may contain modifications to the field logs based on results of laboratory testing and
evaluation. Based on results of the field borings and laboratory testing, subsurface conditions can be
generalized as follows.
The subsurface conditions encountered in the exploratory borings generally consisted of a thin layer
of vegetation and topsoil overlying approximately 3 to 7 feet of sandy lean clay underlain by clayey,
silty sand to the depths explored. The clayey soils were soft to stiff and the sandy soils were loose to
dense based on standard penetration testing. The clay soils were slightly compressive to highly
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 4
expansive based on swell-consolidation test results. The sand is considered non-expansive. Bedrock
was not encountered during the exploration.
The stratification boundaries shown on the boring logs represent the approximate locations where
changes in soil types were observed. In the field, these transitions may be gradual and indistinct. The
conditions observed at the test boring locations may not fully reflect subsurface variations that can
occur over relatively short distances from these points.
Groundwater
Groundwater observations were made while drilling and several days after drilling to detect the
presence and depth to hydrostatic groundwater. Groundwater was encountered during drilling in all
of the borings at depths of 5½ to 7 feet below existing grade. When measured several days later
groundwater was at 6 to 7 feet in the borings. We recommend a minimum 3-foot separation between
foundation elements and slabs to groundwater. Provided grading plans indicate that the grade will be
raised approximately 1½ to 4½ feet above the existing grade, which should provide the necessary
separation. If plans change or that separation can’t be permanently maintained, a well-designed area
underdrain system could be considered to effectively lower and regulate groundwater levels in the
area. The estimated design groundwater elevations, based on the current known conditions, are
indicated on a fence boring diagram in Appendix B.
Groundwater levels may fluctuate over time due to changing hydrologic conditions and other factors
not evident at the time of this report. Depending on the condition of the Timnath Reservoir Inlet
Canal lining, it could be an influence on the local groundwater table while running. We typically see
a rise in groundwater beginning in late spring with elevated levels lasting until late October. To
accurately monitor these fluctuations, long-term observations of water levels in sealed cased wells
would be necessary.
SWELL-CONSOLIDATION TEST RESULTS
The swell-consolidation test evaluates the swell or collapse potential of soils and/or bedrock to
inform foundation, floor slab, and pavement design criteria. In this test, relatively intact samples,
obtained directly from the California sampler, are placed in a laboratory apparatus and subjected to
water inundation under a predetermined load. The swell index represents the percentage of swell or
collapse after the inundation period, based on the sample’s initial thickness under preload. Following
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 5
the inundation period, additional incremental loads are applied to assess swell pressure and/or
consolidation behavior.
For this evaluation, four (4) swell-consolidation tests were conducted on relatively intact soil
samples collected at various depths across the site. The samples tested exhibited (-) 0.4 to (-) 0.8
percent consolidation and (+) 4.1 to (+) 7.3 percent swell when wetted under approximate
overburden pressures. The swell index values ranged from slightly compressive to high swelling in
the upper few feet of soils.
Using the laboratory test results, we estimate that heave of up to 2½ inches is possible for the near
surface soils. More or less heave is possible. A swell mitigation plan should be considered for the
structures and on-site pavement and is discussed further in this report.
It should be noted that the predicted heave represents the potential movement if subsurface moisture
increases significantly after construction. If moisture levels remain stable or increase only
minimally, the full heave potential may not be realized. To mitigate surface water infiltration, proper
site grading, hardscaped surfaces adjacent to the building and drainage swales should be
implemented. Our report includes surface slope and drainage recommendations to reduce this risk.
ANALYSIS AND RECOMMENDATIONS
The subgrades encountered in the borings near anticipated foundation depths generally consisted of
slightly compressive to highly expansive sandy clay. Additionally, some of the near surface soils are
soft with a low bearing capacity. Improvements supported on the existing soils may be susceptible to
post-construction movement without mitigation. To enhance subgrade support and minimize the risk
of post-construction movement, we recommend placing improvements upon a uniform zone of
properly moisture treated and compacted imported structural fill and/or over-excavated, properly
moisture treated and re-compacted native soils. We understand that 1½ to 4½ feet of imported site
grading material is planned to build up the site elevation in this area. We recommend that this
imported material be placed upon improved existing soils. Detailed recommendations for over-
excavation and replacement below structures, flatwork and pavements are provided in the Site
Preparation section. Design and construction criteria for shallow foundations and slab-on-grade
floor systems are outlined in the Foundation and Floor Slabs and Exterior Flatwork section.
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 6
Site Preparation
Prior to placement of any fill and/or improvements, we recommend any existing vegetation, topsoil,
and any unacceptable debris be removed from the planned improvement areas. Any existing building
materials or previously placed, undocumented fill materials should also be removed. After stripping
the site and after making all cuts and prior to placing any fill for the improvements, we recommend
an over-excavation beneath the building foundation, floor slabs, exterior flatwork and pavements.
We recommend over-excavation, moisture conditioning and re-compaction of the upper 3 feet of the
existing soils below the entire building footprint followed by the incorporation of at least 2 feet of
Class 1 structural fill or similar material below foundations and slabs. At least 2 feet of subgrade
below the pavement and exterior flatwork should be over-excavated, properly moisture conditioned
and compacted engineered/controlled fill material.
Once the over-excavation depth is reached, the exposed soils should be scarified to a depth of 9
inches, adjusted in moisture content to within 0% to 3% of standard Proctor optimum moisture
content and compacted to at least 95% of the material's standard Proctor maximum dry density as
determined in accordance with ASTM Specification D698. The over-excavations should extend
laterally 8 inches for every 12 inches of over-excavation depth beyond the edges of the buildings,
exterior flatwork and pavements.
If groundwater or saturated conditions are encountered during the over-excavation, the over-
excavation should stop. The soil should be stabilized, if needed, by crowding 3-inch minus crushed
rock or recycled concrete until the subgrade deflects no more than ½-inch under compactive effort.
Once stabilized, the first fill lift can be placed as specified below.
We recommend all fill materials and foundation wall backfill materials, be placed in loose lifts not to
exceed 9 inches thick and adjusted in moisture content 0% to 3% of optimum for cohesive soils and
±2% for cohesionless granular soils and compacted to at least 95% of the materials standard Proctor
maximum dry density. If the site’s lean clay soils are used as fill material, care will be needed to
maintain the recommended moisture content prior to and during construction of overlying
improvements. Settlement of the backfill soils should be anticipated with total backfill settlement
estimated on the order of 1% of the backfill height.
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 7
Any fill soils used to develop the building elevations should consist of approved, low volume change
materials which are free from organic matter and debris. Imported structural fill materials should be
a Class 1 structural fill or material graded similarly to a CDOT Class 5, 6 or 7 aggregate base with
sufficient fines to prevent ponding of water within the fill. In general, we recommend a material with
low permeability be placed within the building envelope and especially around the exterior of the
foundation to prevent surface water infiltration. Any imported fill materials should be approved by
the geotechnical engineer.
Care should be taken after preparation of the subgrades to avoid disturbing the subgrade materials.
Materials which are loosened or disturbed by construction activities or materials which become wet
and softened or dry and desiccated should be reworked prior to placement of overlying
improvements.
Foundations
Based on materials observed at the test boring locations, it is our opinion that the proposed building
could be supported on a spread footing foundation system bearing on a uniform zone of over-
excavated and properly placed fill materials and structural fill as recommended in the section Site
Preparation. For design of footing foundations bearing on imported, properly placed structural fill,
we recommend using a net allowable total load soil bearing pressure not to exceed 3,000 psf. The
net bearing pressure refers to the pressure at foundation bearing level in excess of the minimum
surrounding overburden pressure. Total loads should include full dead and live loads. For transient
loads such as seismic or wind loads, the bearing pressure can be increased 33 percent. Care should
be taken to see that the foundation bear on uniform materials to prevent differential movement. We
estimate the long-term total settlement of footing foundations designed and constructed as outlined
above would be 1-inch or less with differential settlement expected to be half the total.
Exterior foundations and foundations in unheated areas should be located at least 30 inches below
adjacent exterior grade to provide frost protection. We recommend formed continuous footings have
a minimum width of 16 inches and isolated column footings have a minimum width of 36 inches.
Trenched foundations should not be used in granular subgrades.
No unusual problems are anticipated in completing the excavations required for construction of the
footing foundations. Care should be taken during construction to avoid disturbing the foundation
bearing materials. Materials which are loosened or disturbed by the construction activities or
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 8
materials which become dry and desiccated or wet and softened should be reworked or removed and
replaced prior to placement of foundation concrete.
Foundation and Utility Backfill
Backfill needed to develop site grades following installation of foundations and site utilities should
consist of low volume change materials which are free of organic matter and debris. The site
cohesive soils or similar could be used. Backfill soils should be placed in loose lifts not to exceed 9
inches thick, adjusted in moisture content to within 0% to 3% of optimum moisture content and
compacted to at least 95% of the material’s maximum dry density as determined in accordance with
ASTM Specification D698, the standard Proctor procedure. Care should be taken when backfilling
against laterally unrestrained walls to minimize unbalanced lateral pressures.
Floor Slabs and Exterior Flatwork
Subgrades for floor slabs and exterior flatwork should be prepared as outlined in the section Site
Preparation. For structural design of concrete slabs-on-grade supported on compacted native
cohesive materials, a subgrade modulus of 75 pounds per cubic-inch (pci) could be used. Where
granular structural fill is imported and properly placed, a subgrade modulus of 200 pci could be
used.
Additional floor slab design and construction recommendations are as follows:
• Interior partition walls should be separated/floated from floor slabs to allow for
independent movement. A minimum 2-inch void space should be constructed above,
or below non-bearing partition walls placed on the floor slab. Special framing details
should be provided at door jams and frames within partition walls to avoid potential
distortion. Partition walls should be isolated from suspended ceilings.
• Positive separations and/or isolation joints should be provided between slabs and all
foundations, columns, and utility lines to allow for independent movement.
• Control joints should be provided in slabs to control the location and extent of
cracking.
• Interior trench backfill placed beneath slabs should be compacted in a similar manner
as previously described for on-site materials.
• Floor slabs should not be constructed on frozen subgrade.
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 9
• Other design and construction considerations as outlined in the ACI Design Manual
should be followed.
For interior floor slabs, depending on the type of floor covering and adhesive used, those material
manufacturers may require that specific subgrade, capillary break, and/or vapor barrier requirements
be met. A vapor barrier is most effective when placed between the slab and underlying subgrade or
capillary break material. We understand that this could increase risk of shrinkage curling or cracking
for which, we believe, the concrete mix can be designed to reduce. We would refer you to American
Concrete Institute (ACI) Guide to Concrete Floor and Slab Construction ACI 302.1R-15 for
guidance. The project architect and/or material manufacturers could also be consulted with for
specific under slab requirements.
Care should be exercised after development of the floor slab subgrades to prevent disturbance of the
in-place materials. Subgrade soils which are loosened or disturbed by construction activities or soils
which become wet and softened or dry and desiccated should be removed and replaced or reworked
in place prior to placement of the overlying slabs.
Lateral Earth Pressures
Portions of the new structures or site improvements which are constructed below grade may be
subject to lateral earth pressures. The recommended soil parameters for evaluating lateral earth
pressures at the site are provided below. These parameters, summarized in Table 1, are based on our
experience, general observations of the site soils, and available laboratory test data. If these values
are critical to the design of any site improvements, they should be field-verified prior to construction.
Table 1. Lateral earth pressure parameters.
Material γwet (lb/ft3) Friction Angle, φ Ka Kp Ko
Lean Clay 130 20 0.49 2.04 0.66
Granular Structural Fill 135 35 0.27 3.69 0.42
The parameters presented in Table 1 should be adjusted for saturated and/or buoyant conditions, as
applicable. Construction-phase observation is recommended to account for potential variability in
the retained soils; additional soil parameters may be required depending on actual site conditions.
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 10
The provided parameters do not include a factor of safety and are based on assumed friction angles,
which should be verified once potential material sources have been identified.
Water Soluble Sulfates (SO4)
Results of water-soluble sulfate testing on select samples of the site soil indicate sulfate (SO4)
contents of approximately 0.01% to 0.08%. ACI 318-19, Section 19.3.1 indicates the site soils have a
low risk of sulfate attack on Portland cement concrete or reaction to calcium in chemical stabilizers
such as cement or lime. ACI 318-19 indicates site concrete can be designed with a sulfate exposure
of S0 with no restriction on type of cementitious materials.
Seismic
The site soil conditions generally consist of up to approximately 25 feet of soft to stiff clay over
loose to medium dense clayey silty sand to the bottom of the exploratory borings. In accordance
with ASCE 7 and considering International Building Code, we believe this site would have a
Seismic Site Classification of D. Wind loads, not seismic loads, typically govern design in this area.
If seismic classification is critical to the structural design of this building, additional investigation to
a greater depth with shear wave velocity testing would be needed.
Pavement
We understand that the new site pavements will be private with relatively low traffic volume. Paved
areas could include parking and an access drive for light to medium duty passenger vehicles with
occasional heavier truck traffic. The section provided should also support periodic use of emergency
vehicles up to 85,000 pounds. Our recommendations for minimum pavement sections based on
subgrade conditions and our experience are provided below in Table 2. The recommended pavement
sections are considered minimum.
The subgrades below the site pavements should be developed as recommended in the section titled
Site Preparation. After site grades are established, the pavement subgrades should be proof rolled to
identify any soft and unstable areas. Soft and unstable areas would require removal and replacement
and/or reworking in-place, mechanical stabilization or chemical stabilization consisting of cement or
fly ash (CTS). Mechanical stabilization can likely be achieved using suitable 3-inch minus crushed
rock material or geogrid installation.
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 11
Table 2: Recommended minimum pavement sections for assumed traffic conditions.
Design Information Pavement Sections
Flexible Pavement
Hot Mix Asphalt (HMA)
Aggregate Base Course (ABC)
Moisture/Chemical Treated Subgrade (MTS/CTS)
4̎
6̎
24̎
Rigid Pavement
Portland Cement Concrete (PCC)
Moisture/Chemical Treated Subgrade (MTS/CTS)
6̎
24̎
Aggregate base course should meet CDOT Class 5 or Class 6 aggregate base. Recycled asphalt
(RAP) and recycled concrete (RCP) pavement materials are acceptable as long as they can meet
Class 5 or Class 6 gradation specifications. Those materials should be placed in loose lifts not to
exceed 9 inches, adjusted in moisture content and compacted to achieve a minimum of 95% of
standard Proctor maximum dry density.
Asphalt pavement should be graded as S (75) PG 58-28 or PG 64-22 (HMA) material. If the mix
contains reclaimed asphalt pavement (RAP) material, we recommend using PG 58-28 binder. The
hot mix asphalt should be compacted to achieve 92 to 96% of the mix’s theoretical maximum
specific gravity (Rice Value). Portland cement concrete should be an approved exterior pavement mix
with a minimum 28-day compressive strength of 4,500 psi and should be air entrained.
The diversion of surface drainage away from a pavement is important to the satisfactory
performance of the pavement constructed on the anticipated cohesive soils on this site. Drainage
should provide for the efficient removal of water and snow melt runoff and should prevent ponding
and excessive wetting of subgrade soils.
Regular maintenance is essential to maximize the lifespan of a pavement and should be proactively
planned. For asphalt or concrete pavements crack sealing should limit damage due to water
intrusion. Repairs and sealing of rigid and flexible pavements should take place as soon as possible
after defects appear to be most effective.
Other Considerations
Positive drainage should be developed away from the structures and pavement areas with a
minimum slope of 1 inch per foot for the first 10 feet away from the improvements in landscape
areas. Care should be taken in planning of landscaping adjacent to the buildings to avoid features
Earth Engineering Consultants, LLC
EEC Project No. 1252011
March 28, 2025, Revised April 4, 2025
Page 12
which would pond water adjacent to the foundations or stemwalls. Placement of plants which
require irrigation systems or could result in fluctuations of the moisture content of the subgrade
material should be avoided adjacent to site improvements. Irrigation systems should not be placed
within 5 feet of the perimeter of the buildings and parking areas. Spray heads should be designed
not to spray water on or immediately adjacent to the structures or site pavements. Roof drains
should be designed to discharge at least 5 feet away from the structures and away from the pavement
areas.
The individual contractor(s) should be made responsible for designing and constructing stable,
temporary excavations as required to maintain stability of both the excavation sides and bottom. All
excavations should be sloped or shored in the interest of safety following local and federal
regulations, including current OSHA excavation and trench safety standards.
GENERAL COMMENTS
The analysis and recommendations in this report are based on data obtained from soil borings
conducted at the specified locations, along with other information discussed herein. This report does
not account for potential variations between boring locations or across the site, as such differences
may only become apparent during construction. Should significant variations arise, a re-evaluation
of the report's recommendations will be necessary.
We recommend retaining the geotechnical engineer to review the project plans and specifications to
ensure proper interpretation and integration of the geotechnical recommendations. Additionally, it is
advised to engage the geotechnical engineer for testing and observation during earthwork phases to
verify that the design requirements are met.
This report has been prepared for the exclusive use of Uplift Development Group and their team for
specific application to the project discussed and has been prepared in accordance with generally
accepted geotechnical engineering practices. No warranty, express or implied, is made. In the event
that any changes in the nature, design, or location of the project as outlined in this report are planned,
the conclusions and recommendations contained in this report shall not be considered valid unless
the changes are reviewed and the conclusions of this report are modified or verified in writing by the
geotechnical engineer.
APPENDIX A
Site Photographs
Test Boring Location Diagram
PROSPECT ELF TORAGE HASE
FORT COLLINS, COLORADO
EEC PROJECT NO. 1252011
MARCH 2025
APPENDIX B
Exploratory Boring Logs
Fence Logs
General Notes
Earth Engineering Consultants, LLC
DRILLING AND EXPLORATION
DRILLING & SAMPLING SYMBOLS:
SS: Split Spoon ‐ 13/8" I.D., 2" O.D., unless otherwise noted PS: Piston Sample
ST: Thin‐Walled Tube ‐ 2" O.D., unless otherwise noted WS: Wash Sample
R: Ring Barrel Sampler ‐ 2.42" I.D., 3" O.D. unless otherwise noted
PA: Power Auger FT: Fish Tail Bit
HA: Hand Auger RB: Rock Bit
DB: Diamond Bit = 4", N, B BS: Bulk Sample
AS: Auger Sample PM: Pressure Meter
HS: Hollow Stem Auger WB: Wash Bore
Standard "N" Penetration: Blows per foot of a 140 pound hammer falling 30 inches on a 2‐inch O.D. split spoon, except where noted.
WATER LEVEL MEASUREMENT SYMBOLS:
WL : Water Level WS : While Sampling
WCI: Wet Cave in WD : While Drilling
DCI: Dry Cave in BCR: Before Casing Removal
AB : After Boring ACR: After Casting Removal
Water levels indicated on the boring logs are the levels measured in the borings at the time indicated. In pervious soils, the indicated
levels may reflect the location of ground water. In low permeability soils, the accurate determination of ground water levels is not
possible with only short term observations.
DESCRIPTIVE SOIL CLASSIFICATION
Soil Classification is based on the Unified Soil Classification
system and the ASTM Designations D‐2488. Coarse Grained
Soils have move than 50% of their dry weight retained on a
#200 sieve; they are described as: boulders, cobbles, gravel or
sand. Fine Grained Soils have less than 50% of their dry weight
retained on a #200 sieve; they are described as : clays, if they
are plastic, and silts if they are slightly plastic or non‐plastic.
Major constituents may be added as modifiers and minor
constituents may be added according to the relative
proportions based on grain size. In addition to gradation,
coarse grained soils are defined on the basis of their relative in‐
place density and fine grained soils on the basis of their
consistency. Example: Lean clay with sand, trace gravel, stiff
(CL); silty sand, trace gravel, medium dense (SM).
CONSISTENCY OF FINE‐GRAINED SOILS
Unconfined Compressive
Strength, Qu, psf Consistency
< 500 Very Soft
500 ‐ 1,000 Soft
1,001 ‐ 2,000 Medium
2,001 ‐ 4,000 Stiff
4,001 ‐ 8,000 Very Stiff
8,001 ‐ 16,000 Very Hard
RELATIVE DENSITY OF COARSE‐GRAINED SOILS:
N‐Blows/ft Relative Density
0‐3 Very Loose
4‐9 Loose
10‐29 Medium Dense
30‐49 Dense
50‐80 Very Dense
80 + Extremely Dense
PHYSICAL PROPERTIES OF BEDROCK
DEGREE OF WEATHERING:
Slight Slight decomposition of parent material on
joints. May be color change.
Moderate Some decomposition and color change
throughout.
High Rock highly decomposed, may be extremely
broken.
HARDNESS AND DEGREE OF CEMENTATION:
Limestone and Dolomite:
Hard Difficult to scratch with knife.
Moderately Can be scratched easily with knife.
Hard Cannot be scratched with fingernail.
Soft Can be scratched with fingernail.
Shale, Siltstone and Claystone:
Hard Can be scratched easily with knife, cannot be
scratched with fingernail.
Moderately Can be scratched with fingernail.
Hard
Soft Can be easily dented but not molded with
fingers.
Sandstone and Conglomerate:
Well Capable of scratching a knife blade.
Cemented
Cemented Can be scratched with knife.
Poorly Can be broken apart easily with fingers.
Cemented
Group
Symbol
Group Name
Cu≥4 and 1<Cc≤3E GW Well-graded gravel F
Cu<4 and/or 1>Cc>3E GP Poorly-graded gravel F
Fines classify as ML or MH GM Silty gravel G,H
Fines Classify as CL or CH GC Clayey Gravel F,G,H
Cu≥6 and 1<Cc≤3E SW Well-graded sand I
Cu<6 and/or 1>Cc>3E SP Poorly-graded sand I
Fines classify as ML or MH SM Silty sand G,H,I
Fines classify as CL or CH SC Clayey sand G,H,I
inorganic PI>7 and plots on or above "A" Line CL Lean clay K,L,M
PI<4 or plots below "A" Line ML Silt K,L,M
organic Liquid Limit - oven dried Organic clay K,L,M,N
Liquid Limit - not dried Organic silt K,L,M,O
inorganic PI plots on or above "A" Line CH Fat clay K,L,M
PI plots below "A" Line MH Elastic Silt K,L,M
organic Liquid Limit - oven dried Organic clay K,L,M,P
Liquid Limit - not dried Organic silt K,L,M,O
Highly organic soils PT Peat
(D30)2
D10 x D60
GW-GM well graded gravel with silt NPI≥4 and plots on or above "A" line.
GW-GC well-graded gravel with clay OPI≤4 or plots below "A" line.
GP-GM poorly-graded gravel with silt PPI plots on or above "A" line.
GP-GC poorly-graded gravel with clay QPI plots below "A" line.
SW-SM well-graded sand with silt
SW-SC well-graded sand with clay
SP-SM poorly graded sand with silt
SP-SC poorly graded sand with clay
Earth Engineering Consultants, LLC
IIf soil contains >15% gravel, add "with gravel" to
group name
JIf Atterberg limits plots shaded area, soil is a CL-
ML, Silty clay
Unified Soil Classification System
Soil Classification
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests
Sands 50% or more
coarse fraction
passes No. 4 sieve
Fine-Grained Soils
50% or more passes
the No. 200 sieve
<0.75 OL
Gravels with Fines
more than 12%
fines
Clean Sands Less
than 5% fines
Sands with Fines
more than 12%
fines
Clean Gravels Less
than 5% fines
Gravels more than
50% of coarse
fraction retained on
No. 4 sieve
Coarse - Grained Soils
more than 50%
retained on No. 200
sieve
CGravels with 5 to 12% fines required dual symbols:
Kif soil contains 15 to 29% plus No. 200, add "with sand"
or "with gravel", whichever is predominant.
<0.75 OH
Primarily organic matter, dark in color, and organic odor
ABased on the material passing the 3-in. (75-mm)
sieve
ECu=D60/D10 Cc=
HIf fines are organic, add "with organic fines" to
group name
LIf soil contains ≥ 30% plus No. 200 predominantly sand,
add "sandy" to group name.
MIf soil contains ≥30% plus No. 200 predominantly gravel,
add "gravelly" to group name.
DSands with 5 to 12% fines require dual symbols:
BIf field sample contained cobbles or boulders, or
both, add "with cobbles or boulders, or both" to
group name.FIf soil contains ≥15% sand, add "with sand" to
GIf fines classify as CL-ML, use dual symbol GC-
CM, or SC-SM.
Silts and Clays
Liquid Limit less
than 50
Silts and Clays
Liquid Limit 50 or
more
0
10
20
30
40
50
60
0 10 20 30 40 50 60 70 80 90 100 110
PL
A
S
T
I
C
I
T
Y
I
N
D
E
X
(
P
I
)
LIQUID LIMIT (LL)
ML OR OL
MH OR OH
For Classification of fine-grained soils and
fine-grained fraction of coarse-grained
soils.
Equation of "A"-line
Horizontal at PI=4 to LL=25.5
then PI-0.73 (LL-20)
Equation of "U"-line
Vertical at LL=16 to PI-7,
then PI=0.9 (LL-8)
CL-ML
Rudolph Farms - Prospect Storage Phase 1
Fort Collins, Colorado
Log of Soil Boring
B-1
Project Number:1252011
Drilling Firm:Dakota
Rig Type:CME-55
Drilling Method:4" Auger
Logged By:DG
Date Drilled:03/13/2025
Boring Elevation:4919'
Boring Depth:25.5'
Lat / long:
40.56969, -104.99576
At time of drilling:6'After Drilling:7'
De
p
t
h
(
f
t
)
5
10
15
20
25
30
35
Gr
a
p
h
i
c
L
o
g
Visual Classification and Remarks
3.0
25.5
SANDY LEAN CLAY (CL)
brown
CLAYEY, SILTY SAND (SC)
brown, red, gray
loose to dense
Samples
Sa
m
p
l
e
T
y
p
e
Modified
CA
SS
SS
SS
SS
Sa
m
p
l
e
G
r
a
p
h
i
c
De
p
t
h
o
f
S
a
m
p
l
e
(
ft
)
14
24
9
4
19
N-
V
a
l
u
e
3
34
6
11
11
Lab
Un
c
o
n
f
i
n
e
d
S
t
r
e
n
g
t
h
(P
S
F
)
Mo
i
s
t
u
r
e
C
o
n
t
e
n
t
(
%
)
16.0
9.4
9.7
11.3
9.3
Dr
y
D
e
n
s
i
t
y
(
P
C
F
)
113.6
Li
q
u
i
d
L
i
m
i
t
30
Pl
a
s
t
i
c
i
t
y
I
n
d
e
x
21
%
Fi
n
e
s
39
Lo
a
d
i
n
g
S
t
r
e
s
s
(
P
S
F
)
%
Sw
e
l
l
Sw
e
l
l
P
r
e
s
s
u
r
e
(
P
S
F
)
Su
l
f
a
t
e
(
%
)
Graphics Legend
After Drilling (AD)
At Time of Drilling (ATD)
CL
SC
SS - Small Split Spoon
Modified CA - Modified
California Sampler
DRAFT
Earth Engineering Consultants, LLC | 4396 Greenfield Drive | Windsor, Colorado | 970-545-3908 | www.earth-engineering.com
Rudolph Farms - Prospect Storage Phase 1
Fort Collins, Colorado
Log of Soil Boring
B-2
Project Number:1252011
Drilling Firm:
Rig Type:CME-55
Drilling Method:4" Auger
Logged By:DG
Date Drilled:03/13/2025
Boring Elevation:4918'
Boring Depth:20.5'
Lat / long:
40.56964, -104.99528
At time of drilling:6'After Drilling:7'
De
p
t
h
(
f
t
)
5
10
15
20
25
30
35
Gr
a
p
h
i
c
L
o
g
Visual Classification and Remarks
6.0
20.5
SANDY LEAN CLAY (CL)
brown
stiff to very stiff
CLAYEY, SILTY SAND (SC)
brown
loose to medium dense
Samples
Sa
m
p
l
e
T
y
p
e
Modified
CA
Modified
CA
SS
SS
SS
Sa
m
p
l
e
G
r
a
p
h
i
c
De
p
t
h
o
f
S
a
m
p
l
e
(
ft
)
2
14
4
9
19
N-
V
a
l
u
e
18
10
31
8
7
Lab
Un
c
o
n
f
i
n
e
d
S
t
r
e
n
g
t
h
(P
S
F
)
9000
6000
1500
Mo
i
s
t
u
r
e
C
o
n
t
e
n
t
(
%
)
11.5
27.5
9.1
9.0
26.9
Dr
y
D
e
n
s
i
t
y
(
P
C
F
)
114.3
76.8
Li
q
u
i
d
L
i
m
i
t
37
Pl
a
s
t
i
c
i
t
y
I
n
d
e
x
26
%
Fi
n
e
s
68.6
Lo
a
d
i
n
g
S
t
r
e
s
s
(
P
S
F
)
150
500
%
Sw
e
l
l
7.30
0.0
Sw
e
l
l
P
r
e
s
s
u
r
e
(
P
S
F
)
4500
0
Su
l
f
a
t
e
(
%
)
0.08
Graphics Legend
After Drilling (AD)
At Time of Drilling (ATD)
SC
CL
Modified CA - Modified
California Sampler
SS - Small Split Spoon
DRAFT
Earth Engineering Consultants, LLC | 4396 Greenfield Drive | Windsor, Colorado | 970-545-3908 | www.earth-engineering.com
Dakota
Rudolph Farms - Prospect Storage Phase 1
Fort Collins, Colorado
Log of Soil Boring
B-3
Project Number:1252011
Drilling Firm:
Rig Type:CME-55
Drilling Method:4" Auger
Logged By:DG
Date Drilled:03/13/2025
Boring Elevation:4916'
Boring Depth:20.5'
Lat / long:
40.56943, -104.9956
At time of drilling:6.5'After Drilling:7'
De
p
t
h
(
f
t
)
5
10
15
20
25
30
35
Gr
a
p
h
i
c
L
o
g
Visual Classification and Remarks
6.5
20.5
SANDY LEAN CLAY (CL)
brown
medium stiff
CLAYEY, SILTY SAND (SC)
brown, red, gray
loose to medium dense
Samples
Sa
m
p
l
e
T
y
p
e
Modified
CA
SS
SS
SS
Sa
m
p
l
e
G
r
a
p
h
i
c
De
p
t
h
o
f
S
a
m
p
l
e
(
ft
)
14
9
19
4
N-
V
a
l
u
e
5
27
8
6
Lab
Un
c
o
n
f
i
n
e
d
S
t
r
e
n
g
t
h
(P
S
F
)
Mo
i
s
t
u
r
e
C
o
n
t
e
n
t
(
%
)
19.1
9.1
12.8
19.3
Dr
y
D
e
n
s
i
t
y
(
P
C
F
)
97.2
Li
q
u
i
d
L
i
m
i
t
Pl
a
s
t
i
c
i
t
y
I
n
d
e
x
%
Fi
n
e
s
Lo
a
d
i
n
g
S
t
r
e
s
s
(
P
S
F
)
500
%
Sw
e
l
l
0.0
Sw
e
l
l
P
r
e
s
s
u
r
e
(
P
S
F
)
0
Su
l
f
a
t
e
(
%
)
Graphics Legend
After Drilling (AD)
At Time of Drilling (ATD)
CL
SC
SS - Small Split Spoon
Modified CA - Modified
California Sampler
DRAFT
Earth Engineering Consultants, LLC | 4396 Greenfield Drive | Windsor, Colorado | 970-545-3908 | www.earth-engineering.com
Dakota
Rudolph Farms - Prospect Storage Phase 1
Fort Collins, Colorado
Log of Soil Boring
B-4
Project Number:1252011
Drilling Firm:
Rig Type:CME-55
Drilling Method:4" Auger
Logged By:DG
Date Drilled:03/13/2025
Boring Elevation:4916'
Boring Depth:20.5'
Lat / long:
40.56918, -104.99579
At time of drilling:5.5'After Drilling:6'
De
p
t
h
(
f
t
)
5
10
15
20
25
30
35
Gr
a
p
h
i
c
L
o
g
Visual Classification and Remarks
7.0
20.5
SANDY LEAN CLAY (CL)
brown
soft to stiff
CLAYEY, SILTY SAND (SC)
brown, red, gray
medium dense
Samples
Sa
m
p
l
e
T
y
p
e
Modified
CA
Modified
CA
SS
SS
SS
Sa
m
p
l
e
G
r
a
p
h
i
c
De
p
t
h
o
f
S
a
m
p
l
e
(
ft
)
19
14
4
2
9
N-
V
a
l
u
e
12
4
29
10
11
Lab
Un
c
o
n
f
i
n
e
d
S
t
r
e
n
g
t
h
(P
S
F
)
9000
Mo
i
s
t
u
r
e
C
o
n
t
e
n
t
(
%
)
16.1
15.7
8.1
13.7
25.2
Dr
y
D
e
n
s
i
t
y
(
P
C
F
)
109.2
104.5
Li
q
u
i
d
L
i
m
i
t
Pl
a
s
t
i
c
i
t
y
I
n
d
e
x
%
Fi
n
e
s
Lo
a
d
i
n
g
S
t
r
e
s
s
(
P
S
F
)
150
%
Sw
e
l
l
4.1
Sw
e
l
l
P
r
e
s
s
u
r
e
(
P
S
F
)
1700
Su
l
f
a
t
e
(
%
)
Graphics Legend
After Drilling (AD)
At Time of Drilling (ATD)
SC
CL
SS - Small Split Spoon
Modified CA - Modified
California Sampler
DRAFT
Earth Engineering Consultants, LLC | 4396 Greenfield Drive | Windsor, Colorado | 970-545-3908 | www.earth-engineering.com
Dakota
Rudolph Farms - Prospect Storage Phase 1
Fort Collins, Colorado
Log of Soil Boring
B-5
Project Number:1252011
Drilling Firm:
Rig Type:CME-55
Drilling Method:4" Auger
Logged By:DG
Date Drilled:03/13/2025
Boring Elevation:4917'
Boring Depth:25.5'
Lat / long:
40.56908, -104.99534
At time of drilling:6'After Drilling:6'
De
p
t
h
(
f
t
)
5
10
15
20
25
30
35
Gr
a
p
h
i
c
L
o
g
Visual Classification and Remarks
6.0
25.5
SANDY LEAN CLAY (CL)
brown
soft
CLAYEY, SILTY SAND (SC)
brown, red, gray
loose to medium dense
Samples
Sa
m
p
l
e
T
y
p
e
Modified
CA
SS
SS
SS
SS
Sa
m
p
l
e
G
r
a
p
h
i
c
De
p
t
h
o
f
S
a
m
p
l
e
(
ft
)
9
24
14
4
19
N-
V
a
l
u
e
4
23
13
6
11
Lab
Un
c
o
n
f
i
n
e
d
S
t
r
e
n
g
t
h
(P
S
F
)
1500
Mo
i
s
t
u
r
e
C
o
n
t
e
n
t
(
%
)
15.5
15.2
13.9
15.9
10.7
Dr
y
D
e
n
s
i
t
y
(
P
C
F
)
97.2
Li
q
u
i
d
L
i
m
i
t
31
21
Pl
a
s
t
i
c
i
t
y
I
n
d
e
x
19
3
%
Fi
n
e
s
55.3
29.2
Lo
a
d
i
n
g
S
t
r
e
s
s
(
P
S
F
)
500
%
Sw
e
l
l
0.0
Sw
e
l
l
P
r
e
s
s
u
r
e
(
P
S
F
)
0
Su
l
f
a
t
e
(
%
)
0.01
Graphics Legend
After Drilling (AD)
At Time of Drilling (ATD)
CL
SC
SS - Small Split Spoon
Modified CA - Modified
California Sampler
DRAFT
Earth Engineering Consultants, LLC | 4396 Greenfield Drive | Windsor, Colorado | 970-545-3908 | www.earth-engineering.com
Dakota
EL
E
V
A
T
I
O
N
(
f
e
e
t
)
4890
4895
4900
4905
4910
4915
4920
SC
CL
SC
CL
SC
CL
SC
CL
SC
CL
B-1
Elev: 4919.0 ft
Depth: 25.5 ft
B-2
Elev: 4918.0 ft
Depth: 20.5 ft
B-3
Elev: 4916.0 ft
Depth: 20.5 ft
B-4
Elev: 4916.0 ft
Depth: 20.5 ft
B-5
Elev: 4917.0 ft
Depth: 25.5 ft
6
11
34
3
11
18
8
10
31
7
8
27
6
5
11
10
4
12
29
23
11
13
4
6
Prospect Self Storage Phase 1Fort Collins, Colorado
EEC Project No. 1252011
Earth Engineering Consultants, LLC | 4396 Greenfield Drive | Windsor, Colorado | 970-545-3908 | www.earth-engineering.com
EXPLORATION LOG LEGEND
Exploration designation
Exploration Top Elevation
Exploration Depth
First water encounter
Second water encounter
B-1
Elev: 4800 ft
8
Depth: 25 ft
N Value
Soil/Rock Strata as Described
in Exploration Log
Sampler graphic
LEGEND KEY
CL
SC(Approximate)
SS - Small Split Spoon
Modified CA - Modified
California Sampler
WC = 9.4%
WC = 9.7%
WC = 11.3%
WC = 9.3%
LL = 30; PI = 21WC = 16.0%DD = 113.6 PCFFI = 39%
WC = 9.1%
WC = 9.0%
WC = 26.9%
LL = 37; PI = 26SW = 7.3%WC = 11.5%DD = 114.3 PCFFI = 68.6%
SW = -0.4%WC = 27.5%DD = 76.8 PCF
WC = 12.8%
WC = 9.1%
WC = 19.3%
SW = -0.4%
WC = 19.1%DD = 97.2 PCF
SW = 4.3%
WC = 16.1%DD = 109.2 PCF
WC = 15.7%DD = 104.5 PCF
WC = 8.1%
WC = 13.7%
WC = 25.2%
LL = 21; PI = 3WC = 13.9%FI = 29.2%
WC = 15.9%
WC = 10.7%
WC = 15.2%
LL = 31; PI = 19SW = -0.8%WC = 15.5%DD = 97.2 PCFFI = 55.3%
EL
E
V
A
T
I
O
N
(
f
e
e
t
)
4890
4895
4900
4905
4910
4915
4920
SC
CL
SC
CL
SC
CL
SC
CL
SC
CL
B-1
919.0 ftElev: 4
Elev:4893.5 ft
Depth: 25.5 ft
B-2
918.0 ftElev: 4
897.5 ftElev: 4
20.5 ftDepth:
B-3
Elev: 4916.0 ft
Elev: 4895.5 ft
Depth: 20.5 ft
B-4
Elev: 4916.0 ft
Elev: 4895.5 ft
Depth: 20.5 ft
B-5
.0 ftElev: 4917
1.5 ftElev: 489
Depth: 25.5 ft
6
11
34
3
11
18
8
10
31
7
8
27
6
5
11
10
4
12
29
32
11
31
4
6
LEGEND KEY
CL
SC
Prospect Self Storage Phase 1
Fort Collins, Colorado
EEC Project No. 1252011
Earth Engineering Consultants, LLC | 4396 Greenfield Drive | Windsor, Colorado | 970-545-3908 | www.earth-engineering.com
Final Floor Elevation = 4920.45'
4912'
4911'
4909'
4910'
4911'
4912'Current Estimated Design Groundwater Elevation
Note: Elevations were estimated using the Uplift Self Storage Overall Grading Plan by Kelly Development Services, LLC
Project No. 2109.01 dated February 12, 2025 and the "Existing and Overlot Grading" plan provided by the client.
Current Estimated Static Groundwater Level
Provided Final Floor Elevation
APPENDIX C
Laboratory Test Results
Project:
Location:
Project #:
Date:
Material Description:Brown Sandy Lean Clay
Beginning Moisture: 11.5%Dry Density: 114.3 pcf Ending Moisture: 18.7%
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Pe
r
c
e
n
t
M
o
v
e
m
e
n
t
Load (TSF)
Sw
e
l
l
Co
n
s
o
l
i
d
a
t
i
o
n
Project:
Location:
Project #:
Date:
Material Description:Brown, Sandy Lean Clay
Beginning Moisture: 27.5%Dry Density: 86.1 pcf Ending Moisture: 29.9%
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Pe
r
c
e
n
t
M
o
v
e
m
e
n
t
Load (TSF)
Sw
e
l
l
Co
n
s
o
l
i
d
a
t
i
o
n
Project:
Location:
Project #:
Date:
Material Description:Brown, Sandy Lean Clay
Beginning Moisture: 19.1%Dry Density: 97.2 pcf Ending Moisture: 18.9%
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Pe
r
c
e
n
t
M
o
v
e
m
e
n
t
Load (TSF)
Sw
e
l
l
Co
n
s
o
l
i
d
a
t
i
o
n
Project:
Location:
Project #:
Date:
Material Description:Brown, Sandy Lean Clay
Beginning Moisture: 16.1%Dry Density: 109.2 pcf Ending Moisture: 21.1%
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Pe
r
c
e
n
t
M
o
v
e
m
e
n
t
Load (TSF)
Sw
e
l
l
Co
n
s
o
l
i
d
a
t
i
o
n
Project:
Location:
Project #:
Date:
Material Description:Brown Sandy Lean Clay
Beginning Moisture: 15.5%Dry Density: 97.2 pcf Ending Moisture: 21.4%
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Pe
r
c
e
n
t
M
o
v
e
m
e
n
t
Load (TSF)
Sw
e
l
l
Co
n
s
o
l
i
d
a
t
i
o
n
2 1/2"(63 mm)
2"(50 mm)
1 1/2"(37.5 mm)
1"(25 mm)
3/4"(19 mm)
1/2"(12.5 mm)
3/8"(9.5 mm)
No. 4 (4.75 mm)
No. 8 (2.36 mm)
No. 10 (2 mm)
No. 16 (1.18 mm)
No. 30 (0.6 mm)
No. 40 (0.425 mm)
No. 50 (0.3 mm)
No. 100 (0.15 mm)
No. 200 (0.075 mm)
Project:Rudolph Farms - Prospect Storage Phase 1
Location:Fort Collins, Colorado
Project No:1252011
Sample ID:B1 S2 9
Date:March 2025
94
74
51
10
6.8
46
34
22
18
15
100
100
100
100
99
EARTH ENGINEERING CONSULTANTS, LLC
SUMMARY OF LABORATORY TEST RESULTS
Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136)
100
Sieve Size Percent Passing
EARTH ENGINEERING CONSULTANTS, LLC
Summary of Washed Sieve Analysis Tests (ASTM C117 & C136)
Date:
Project:
Location:
Project No:
Sample ID:
Cobble Silt or ClayGravel
Coarse Fine
Sand
Coarse Medium
March 2025
19.00 3.31 2.30
Rudolph Farms - Prospect Storage Phase 1
Fort Collins, Colorado
1252011
B1 S2 9
D100 D60 D50
0.98 0.15
Fine
22.34 1.98
D30 D10 Cu CC
6"
5"
4"
3"
2.5"
2"
1.5"
1"
3/4"
1/2"
3/8"
No. 4
No. 8
No. 10
No. 16
No. 30
No. 40
No. 50
No. 100
No. 200
0
10
20
30
40
50
60
70
80
90
100
0.010.11101001000
Fi
n
e
r
b
y
W
e
i
g
h
t
(
%
)
Grain Size (mm)
Standard Sieve Size
2 1/2"(63 mm)
2"(50 mm)
1 1/2"(37.5 mm)
1"(25 mm)
3/4"(19 mm)
1/2"(12.5 mm)
3/8"(9.5 mm)
No. 4 (4.75 mm)
No. 8 (2.36 mm)
No. 10 (2 mm)
No. 16 (1.18 mm)
No. 30 (0.6 mm)
No. 40 (0.425 mm)
No. 50 (0.3 mm)
No. 100 (0.15 mm)
No. 200 (0.075 mm)
Project:Rudolph Farms - Prospect Storage Phase 1
Location:Fort Collins, Colorado
Project No:1252011
Sample ID:B3 S2 9
Date:March 2025
91
69
45
12
8.6
41
31
22
19
16
100
100
100
100
97
EARTH ENGINEERING CONSULTANTS, LLC
SUMMARY OF LABORATORY TEST RESULTS
Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136)
100
Sieve Size Percent Passing
EARTH ENGINEERING CONSULTANTS, LLC
Summary of Washed Sieve Analysis Tests (ASTM C117 & C136)
Date:
Project:
Location:
Project No:
Sample ID:
Cobble Silt or ClayGravel
Coarse Fine
Sand
Coarse Medium
March 2025
19.00 3.83 2.83
Rudolph Farms - Prospect Storage Phase 1
Fort Collins, Colorado
1252011
B3 S2 9
D100 D60 D50
1.09 0.11
Fine
35.01 2.83
D30 D10 Cu CC
6"
5"
4"
3"
2.5"
2"
1.5"
1"
3/4"
1/2"
3/8"
No. 4
No. 8
No. 10
No. 16
No. 30
No. 40
No. 50
No. 100
No. 200
0
10
20
30
40
50
60
70
80
90
100
0.010.11101001000
Fi
n
e
r
b
y
W
e
i
g
h
t
(
%
)
Grain Size (mm)
Standard Sieve Size