HomeMy WebLinkAboutLeachfield Soil Evaluation
Project #23‐02
Date: 10/30/23
Mindy Kennedy
84 Lariat Road
Silt, CO 81652
970‐319‐7693
mindymaekylie55@gmail.com
RE: New ResidenƟal Leach Field Soil EvaluaƟon
Dear Mrs. Kennedy,
Free Range Engineering (FRE) was asked to perform a visual and tacƟle soil evaluaƟon for a proposed
leach field located at 84 Lariat Road in Silt, Colorado. This memo presents the invesƟgaƟon details and
soil characterisƟcs and subsurface condiƟons observed at the residence on Saturday, October 28, 2023.
Two test pits were excavated south of the residence with a Bobcat 435 excavator supplied by the
property owner. Test Pit 1 (TP‐1), to the north, was excavated to a depth of 8.5 feet and Test Pit 2 (TP‐2),
to the south, reached a depth of 7 feet.
Soil samples were collected at depths of 4 feet and 8 feet in TP‐1 and 3 feet and 6 feet in TP‐2. These
samples were hydrated with water for 24 hours and then examined to evaluate the percentages of sand,
silt and clay. Generally, the soil in both test pits correlates to a Type 2A based on USDA Table 10‐1 as
presented below with an increasing percentage of clay below 7.5 feet.
Ground water was not encountered in the test pits at the Ɵme of excavaƟon. Neither bedrock nor a
limiƟng layer were encountered to the depths explored.
Table 10‐1 Soil Treatment Area Long‐Term Acceptance Rates by Soil Texture, Soil Structure, PercolaƟon
Rate and Treatment Level
Soil Type USDA Soil
Texture
USDA Soil
Structure‐Type
USDA Soil
Structure‐Grade
Treatment
Level 1
(MPI)
Treatment
Level 1
2A Silt Loam GR 0‐Structureless 26‐40 0.50
Respecƞully SubmiƩed,
Kevin Dye, P.E.
AƩachments: Test Pit Logs
10/30/23
Project Number:23-02
Project Name:Kennedy Leach Field
City, State: 84 Lariat Road, Silt County: Garfield
Weather Conditions:Clear, calm
Date: 10/28/23 Time: 10:00-11:30 AM
Driller: N/A
Mini Excavator:Bobcat 435
Method of Drilling:N/A Hammer: N/A
Ground Water GPS Coordinates: WGS 84 Logged by: KD
Date:N°Test Pit #:TP-1 Page ____1__ of ___1___
Time:W°Investigation Notes:
Depth:None Elevation: feet
Depth
(feet)
Sample
Type (1)
Blow Count
#/#/#
Total Core
Recovery
Core RQD
(>4-in)Gr
a
p
h
i
c
Lo
g
4 GB SILT, sand, clay, light brown, dry to moist, non-plastic
8 GB SAME as above but more clay, moist, low to medium plasticity
Bottom of pit at 8.5 feet
(1) SPT=Split Spoon, MC=Modified California Barrel, ST=Shelby Tube, CO=Core (Size), GB=Grab/Bulk Sample
Free Range Engineering
Sketch of Surface Conditions and Surrounding
Relative Features:
EXAMPLE: Sandy CLAY FILL, brown-light gray, low plastic, moist, stiff to very
stiff, organics, calcareous, odor
VERY IMPORTANT!! MARK CHANGE IN SOIL IN GRAPHIC LOG
Project Number:23-02
Project Name:Kennedy Leach Field
City, State: 84 Lariat Road, Silt County: Garfield
Weather Conditions:Clear, calm
Date: 10/28/23 Time: 10:00-11:30 AM
Driller: N/A
Mini Excavator:Bobcat 435
Method of Drilling:N/A Hammer: N/A
Ground Water GPS Coordinates: WGS 84 Logged by: KD
Date:N°Test Pit #:TP-2 Page ____1__ of ___1___
Time:W°Investigation Notes:
Depth:None Elevation: feet
Depth
(feet)
Sample
Type (1)
Blow Count
#/#/#
Total Core
Recovery
Core RQD
(>4-in)Gr
a
p
h
i
c
Lo
g
3GB
SILT, sand, clay, light brown, dry to moist, non-plastic
6GB
Bottom of pit at 7.0 feet
(1) SPT=Split Spoon, MC=Modified California Barrel, ST=Shelby Tube, CO=Core (Size), GB=Grab/Bulk Sample
Free Range Engineering
Sketch of Surface Conditions and Surrounding
Relative Features:
EXAMPLE: Sandy CLAY FILL, brown-light gray, low plastic, moist, stiff to very
stiff, organics, calcareous, odor
VERY IMPORTANT!! MARK CHANGE IN SOIL IN GRAPHIC LOG