Soils Report 001Prairie Plaza Lot 4
Soils Report For Drainage Purposes
Site Address: 1202 Yelrn Ave E Yelm, WA 98597
Tax Parcel Number: 22730110103
~F.
Prepared For: Forbest Partners, LLC r;<,!
PO Box 12540 FG,
Olympia, WA 98508-2540 °t;r
(360) 352-2004
Contact: Mike McKinnon
Prepared By: Parnell Engineering
10623 Hunters Lane S.E.
Olympia, WA 98513
(360) 491-3243
Contact: William Parnell, P.E.
PE
PARNELL ENGINEERING
SOIL EVALUATION REPORT
FORM 1: GENERAL SITE INFORMATION
PROJECT TITLE: Prairie Plaza Lol4 SHEET: 1 OF 1
PROJECT NO. :06100 DATE: 1/20/06
PREPARED BY :William Parnell, P.E.
1. SITE ADDRESS: 1202 Yelm Ave. E Yelm, Wa. 98597
TAX PARCEL NUMBER: 22730110103 -Lot 4
2. PROJECT DESCRIPTION: Commercial Development
3. SITE DESCRIPTION: The triangular project site is currently unoccupied. Site relief is nearty
level except fora 7°k west to east grade along the eastern etlge of the parcel. Elevations range
from a high of 349 ft. to a low of 347 ft. There is no site distinguishing features. Site vegetation
consists of uncropped feld grasses antl low density scotch broom brush. The project site is
bounded by fully tleveloped commercial property to the south and east, undeveloped commercial
property to the north and Plaza Drive N.E. to the west. Access is off N.E. Plaza Drive. On-site soils
are swell-drainetl Spanaway series formed in glacial outwash.
4. SUMMARY OF SOILS WORK PERFORMED: One test pit was excavated by backhoe to a
depth of 156" below the existing grade. Soils were inspectetl by entering and visually logging
each test pit to a depth of four feet. Soils beyontl four feet were inspected by examining backhoe
tailings. One double ring infiltration test was completed at 72" below the existing grade. A test pit
soil log data sheet and a double ring infiltration test result are inclutletl in this report.
5. ADDITIONAL SOILS WORK RECOMMENDED: Additional soils work should not be necessary
unless drainage infiltration facilities are located outside the general area encompassed by the soil
test pits.
6. FINDINGS: The Natural Resource Conservation Service soil survey for Thurston County
mapped the on-site soils as a Spanaway Stoney Sandy Loam (112). The test pit confirmed the
Spanaway designation generally profling a stoney fne sandy loam surface soil overtying an
extremely gravelly & cobbley coarse sand substratum. The substratum gravels and sands were
slightly to moderately loose. Winter water table was present at 120" below the existing grade. A
double ring infiltration test completetl at 80" below the existing gratle yieltletl an infiltration rate of
205 inlhr.
7. RECOMMENDATIONS: The Spanaway soil series is a somewhat excessively drainetl soil that
farmed in gravelly glacial outwash. Infiltration rates are generally rapid in the substratum soils. The
specifed substratum C-horizon soils shoultl be targetetl for all tlrainage infiltration facilities as
notetl in the attached soil log data sheet. A tlesign infiltration rate of 20 in/hr or less would be
appropriate for these targetetl soils. Winter water table must be a consideration in the tlesign of all
drainage infiltration facilities.
During construction, care must be taken to prevent the erosion of exposed soils. Drainage facility
infiltration surtaces must be properly protected from contamination by the fine-grained upper
horizon soils and from compaction by construction site activities. Soils not property protected will
cause tlrainage infiltration facilities to prematurely fail.
I hereby certify that I prepared this report, and conducted or supervised the pertormance of related
work. I certify that I am qualified to do this work. I represent my work to be complete an accurate
within the bounds of uncertainty inherent to the practice of soils science, and to be suitable for its
intended use, jj~,^,
SIGNED: W
/ @
DATE: r/ w~06 ~ ~ ~~
F O
SOIL EVALUATION REPORT
FORM 2: SOIL LOG INFORMATION
PROJECT TITLE: Prairie Plaza Lot 4 SHEET: 1 OF 1
PROJECT NO. :06100 DATE: 1/19/06
PREPARED BY :William Parnell, P.E.
SOIL LOG: #i
LOCATION: 60 h. west and 140 tt. south of the northeast property corner.
1. TYPES OF TEST DONE: 2. SCS SOILS SERIES: 3. LAND FORM:
Double Ring Infltrafion Spanaway (112) Terrace
4. DEPOSITION HISTORY: 5. HYDROLOGIC SOIL 6. DEPTH OF SEASONAL HW:
GROUP:
Glacial Outwash A/B 120"
7. CURRENT WATER 8. DEPTH TO IMPERVIOUS 9. MISCELLANEOUS:
DEPTH: LAYER:
120" Greater than bottom of hole Nearly Level
10. POTENTIAL FOR: EROSwrv RUNOFF PorvDING
Minimal Slow Minimal
11. SOIL STRATA DESCRIPTION: See Following chart
12. SITE PERCOLATION RATE: See FSP
13. FINDINGS & RECOMMENDATIONS: Static water level was 1 20" below the existing grade. Use a
design infiltration rate of 20 in/hr or less (or drainage infiltration facilities located in the C2 horizon soils.
Soils Strata Description
Soil Log #1
Horz DeoN Color Te#ure %CL %ORG CF STR MOT IND CEM ROO <p FSP
A 0'- 24" 10YRZ11 GrVFSaLm <20 <5 <15 1SBK - - - ff 2-6 2
Bw1 24"- 32' 70VR4/2 GrVFSaLm <20 <26 156K - - - K 2-6 3
fiW2 32"- 34' fOVR4/6 VGrLmSa q0 - <55 SG - - - - 620 6
G1 34"- 6T 10VR5/4 ExGrCSa <2 - <85 SG - - - - >20 >40
many stones
G2 6T-156' t0YR5/1 E%GrBGOb <1 - <gp SG - - - - >20 >q0
CSa
some stones
Abbreviations
Textural Class
(Texture) Structure
(STR) Grades of Structure
Cobble -Cob Granular - Gr Stoon - 3
Stone - St Block - Blk Moderate - 2
Gravell - Gr Plat - PI Weak - 1
Sand - Sa Massive - Mas
Loam - Lm Sin le Grained - SG
Silt - Si Sub-An ular Block - SBK
Clayey - CI
Coarse - C
Ve - V
EMremel - Ex
Fine - F
Medium - M
Induration & Cementation
(IND) (CEM)
Weak - Wk
Moderate -Mod
Strong - Str
Mottles MOT
7 Letter Abundance 1st Number Size 2nd Letter Contrast
Few - F Fine - 1 Faint - F
Common - C Medium - 2 Distinct - D
Many - M Coarse - 3 Prominent - P
Roots (ROO)
1st Letter Abundance 2nd Letter Size
Few -f Fine -f
Common - c Medium - m
Man - m Coarse - c
<X> -Generalized range of infiltration rates from SCS soil survey (<X>)
FSP -Estimated Field Saturated Percolation rate based on horizon specific
factors.
DOUBLE RING INFILTRATION TEST
Prairie Plaza Lot 4
Test Date :1/19/2006
Completed By: William Parnell, P.E.
PE Job #06100
DOUBLE RING INFILTRATION TEST
Test Hole # 1 (test run @ 72" below existing ground surface )
Start Sto Ela sed Time Total Dro Infiltration Rate
( Min) (Min) (Min) (Inches) (In/Hr
0 1' 45" 1' 45" 6
1' 45" 3' 45" 2' 00" 6
3' 45" 5' 30" 1' 45" 6
5' 30" 7' 15" 1' 45" 6
T 15" 9' 00" 1' 45" 6
s' oo^ 1a as° r as" s
10' 45" 12' 15" 1' 45" 6
12' 15" 14' 00" 1' 45" 6
14' 00" 15' 45" 1' 45" 6
15' 45" 1 T 30" 1' 45" 6
1T 30" 19' 15" 1' 45" 6
19' 15" 21' 00" 1' 45" 6 205