Correspondence E N V I R O N M E N T A L •
PBS
MEMORANDUM
TO: Mr. John B. McCroskey FROM: Brett V. Danko c3V
% Mr. George Funkhouser
Meadowlark Partners, LLC DATE: December 2, 1996
1750 SW Skyline Blvd, Suite 224
Portland, Oregon 97221 PBS PROJECT NO.: 12189.03
RE: Tax Lots 2600 & 2700, SW 69th Avenue
Tigard, Oregon
This memo presents the general soil conditions that may be encountered during site excavation and
grading for the proposed dental clinic to be constructed at the above mentioned property. Soil conditions
are interpreted from geologic maps, and observations of neighboring construction projects to the east of
the subject property. Since no subsurface investigation has been conducted, actual site conditions cannot
be fully determined and actual soil conditions may vary.
1) The top 1 to 2 feet would consist of topsoil composed of soft silt mixed with organic material
and abundant roots. The area around the house and garage would be composed of silt mixed
with gravel, building materials, and organic matter.
2) Below 2 feet in depth, the site soils would consist of soils of the Willamette Silt Formation which
typically includes silt, clay, and sand layers and also mixtures of silt, clay, and sand.
3) Lava flows of the Boring Basalts are present to the north and east of the site. It is possible that •
this unit may be encountered in soils beneath the property, however, this can only be determined
through subsurface exploration.
c We believe that the anticipated soil c dion aons at the site would be able to support the propose �ntal
building, however, the s,dils would be managtfhrough a speckWsign p,<ogranrdcveiop m our
subsurface exploration program. This would include specifications related to the following:
1) The removal of roots and organic debris, building materials, solid waste, underground tanks, and
any other materials that may cause settlement.
2) Compaction and in -place density testing of native soils and engineered backfill materials within
the building pad area and in paved portions of the site.
ENVIRONMENTAL
MANAGEMENT
AND CONSULTING
1220 SW Morrison Street, Suite 600 Portland, OR 97205 503/248 -1939 Fax 503/248 -0223
DENVER EUGENE PORTLAND RIC.111. SEATTLF.
r .... -. . -. ..
E N V I R O N M E N T A L PBS
25 November 1996 •
John B. McCroskey
c/o George Funkhouser
Meadowlark Partners
1750 SW Skyline Boulevard, Suite 224
Portland, Oregon 97221
Re: Tax Lots 2600, 2700
69th & Hampton Streets, Tigard, Oregon
PBS Project # 12189.02
Dear Mr McCroskey:
PBS has completed its wetland determination for above - referenced site. This letter presents the scope
of work for the project, and our findings and conclusions.
1.0 Scope of Work
The scope of work for the project consisted of the following items:
1) Document Review
a) Review of National Wetland Inventory Map to determine if the subject property, or
portions of the subject property, are within previously identified wetland areas;
b) Review of appropriate USGS Quadrangle to characterize local drainage patterns;
c) Review of appropriate local soil survey to determine what soils are mapped on the subject
property and whether they are classified as hydric (developed under reducing (saturated)
conditions), or non - hydric.
2) Conduct a site visit to confirm local drainage patterns and to observe obvious evidence of the
presence of wetlands such as wetland vegetation, standing water, creeks, etc..
ENVIRONMENTAL
MANAGEMENT
AND CONSULTING
1220 SW Morrison Street, Suite 600 Portland, OR 97205 503/248.1939 Fax 503/248 -0223
DENVER EUGENE PORTLAND RICIII.AND SEAI I LE
'
• John McCroskey
Re: Tax Lots 2600, 2700
25 November 1996
Page 2
2.0 Findings
Document Review
1) National Wetland Inventory Map (Lake Oswego)- No wetlands are mapped on the subject
property or near vicinity.
2) USGS Lake Oswego Quadrangle- No surface water features are depicted on the subject property.
Intermittent stream depicted short distance to the south. Topography on the subject is relatively
flat, sloping gently to the southwest.
3) Washington County Soil Survey (Map Sheet #12, Inset A)- Three soil types are shown are
depicted on or adjacent to the subject property. These soil types are listed below.
Type 1 Aloha Silt Loam- Non - hydric
Type 22 Huberly Silt Loam- Hydric, described as poorly drained with a fragipan (clay layer) at
depths of approximately 2 feet. This soil type is shown in areas east and south of the property.
Type 37 C Quatama Silt Loam- Non - Hydric
Hydric soils are defined as those developing under reducing (saturated, anaerobic) conditions and are
sometimes associated with wetlands.
Site Visit
PBS visited the site on November 20, 1996. The site is relatively flat, sloping gently to the south and
west. The east portion of the property is occupied by various buildings, vehicles, etc.. The remainder
of the site is forested with what appears to be a second or third growth deciduous forest. Vegetation
observed included species which are categorized as upland (i.e. non - wetland) species including white oak,
swordfern, himalayan blackberry, etc.. No typical wetland species, standing water or surface water
features were observed.
3.0 Conclusions
Based upon the findings of this study, no jurisdictional appear to be present at the site.
I hope this information is sufficient for you needs. Please contact me if you have any questions.
Sincerely.
-
Tom Archer
Project Manager
• if .. . ,.,
E N V I R O N M E N T A L
25 November 1996
Invoice No. 12189.02 -1
Project No. 12189.02
Mr. John B. McCroskey
c/O George Funkhouser
Meadowlark Partners, LLC
1750 SW Skyline Blvd., Suite 224
Portland, OR 97221
For: Wetland Determination
Tax Lots 2600 & 2700 on SW 69th Avenue, Tigard, Oregon
Environmental Services: Wetland Determination - Project Complete
FEE:
Total Fee $500.00
Percent Complete 100.0 Total Earned $500.00
Previous Fee Billing 0.00
Current Fee Billing $500.00
TOTAL THIS INVOICE $500.00
ENVIRONMENTAL
MANAGEMENT
AND CONSULTING
1220 SW Morrison Street, Suite 600 Portland, OR 97205 503/248 -1939 Fa 503/248 -0223
DENVER EUGENI. PORTLAND RICIII.AND SIAITE I