HomeMy WebLinkAboutGEO2010-00025 - BLD Engineering / Geo-tech Reports - 6/11/2010 MASON COUNTY
DEPARTMENT OF COMMUNITY DEVELOPMENT
Planning Division
P O Box 279, Shelton, WA 98584
flo
(360)427-9670
Geotechnical Assessment Review Acceptance Letter
June 11, 2010
ERIN PAYSON
101 E STEVES PL
ALLYN WA 98524
Case No.: GE02010-00025
Parcel No.: 122203490362
Proiect Description: geo review for addition
The Geotechnical Assessment for ERIN PAYSON has been received and reviewed by the
Planning Department. The assessment was prepared by Wesley R. Johnson dated 5/24/2010.
Based on the certification provided by the licensed engineer/geologist, the referenced Geological
Assessment was prepared in general accordance with the requirements in the Mason County
Resource Ordinance, Landslide Hazard Areas 17.01.100.E.4. Mason County considers the review
valid until such time as scope of project, site conditions, and/or regulations change. Should the
scope of work, site conditions, and/or regulations change after the original review, then an
addendum from the original author of the assessment may be required to address these changes.
The assessment would only be re-reviewed if a permit for development were submitted after these
changes occur. Mason County does not certify the quality of the work done in this Geological
Assessment.
Please contact me at (360) 427-9670, ext. 365 if you have questions.
Sincerely
,
6V41
Allan Borden
Land Use Planner
Mason County Planning Department
Comments:
6/11/2010 Page 1 of 1 GE02010-00025
bLk->Z-'71U -Ujo0t)
SLOPE ASSESSMENT
PROPOSED SINGLE FAMILY RESIDENCE
101 EAST STEVES PLACE
ALLYN, WA
CLIENT:
Attn: Mr. Steve Payson
3301 West Highway 16
Port Orchard, WA 98367
BY:
N.L. OLSON AND ASSOCIATES, INC.
2453 BETHEL AVE. SE
PORT ORCHARD, WA 98366
(360) 876-2284
JOB NO. 7450-10
tiY R. !p�
- PE.39359 t{�
�fs�ON ALG��
MAY 2010
N.L. OLSON & ASSOCIATES INC.
'Engineering, Planning and Surveying
May 24, 2010 Project Number: 7450-10
Attn: Attn: Mr. Steve Payson
3301 West Highway 16
Port Orchard, WA 98367
Subject: Slope Assessment
Proposed Single Family Residence
101 East Steves Place
Allyn, WA
Mason County Parcel #: 122203490362
Dear Mr. Payson;
This report presents the results of our site assessment for the referenced project. The
assessment was done per Mason County Resource Ordinance, 17.01.100 landslide hazard
areas, section E, special reports, page 6 of 15, dated December 27, 2006.
NLO has included Mason County Department of Community Development Submittal Checklist
for a Geological Assessment in the Appendix B of this report.
We appreciate the opportunity to be of service to you on this project. If we can be of further
assistance or if you have any questions regarding this project, please contact our office.
Sincerely,
Wesley R. Jo nson, P.E.
Project Engineer
P.O. Box 637. 2453 Bethel Avenue • Port Orchard, Washington 98366
Phone: 1(800) 755-1282 Fax: (360) 876-1487
CADocuments and Settings\WJohnson\My Documents\Project Folder\7450 Payson Slope\Payson Slope Assessment.doc
TABLE OF CONTENTS
INTRODUCTION...................................................................................................................... 1
SITELOCATION....................................................................................................................... 1
SITECONDITIONS.................................................................................................................... 1
PROPOSED DEVELOPMENT...................................................................................................... 1
FIELD INVESTIGATION.............................................................................................................. 1
SiteSoil Conditions............................................................................................................ 2
Groundwater...................................................................................................................... 2
AVAILABLE GEOLOGIC SOILS INFORMATION .............................................................................. 2
DEPARTMENT OF ECOLOGY WATER WELL REPORT................................................................... 2
SLOPERECONNAISANCE ......................................................................................................... 2
HISTORICAL LANDSLIDE RESEARCH.......................................................................................... 2
UPSLOPE GEOMORPHOLOGY................................................................................................... 3
UPLANDWATER BODIES.......................................................................................................... 3
WETLANDS............................................................................................................................. 3
CONCLUSIONS AND RECOMMONDATIONS ........................................................................4
REPORTLIMITATIONS...........................................................................................................4
VICINITYMAP ...........................................................................................................FIGURE 1
SITESKETCH............................................................................................................FIGURE 2
CROSSSECTION A-A...............................................................................................FIGURE 3
SLOPESTABILITY MAP...........................................................................................FIGURE 4
APPENDIX A—TEST PIT LOGS
APPENDIX B —MASON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT
SUBMITTAL CHECKLIST
SLOPE ASSESSMENT
PROPOSED SINGLE FAMILY RESIDENCE
101 EAST STEVES PLACE
ALLYN, WA
INTRODUCTION
This report presents the results of our fieldwork for the referenced project. In the following, we
present our findings and conclusion of our Geologic Assessment.
SITE LOCATION
The property is located at the address of 101 East Steves Place, Allyn, WA and by Section 20,
Township 22 North, Range 01 West, Mason County, Washington. The Vicinity Map for the
property has been illustrated on Figure 1.
SITE CONDITIONS
The site is bordered by undeveloped land to the west and north, to the south by a single family
residence and beyond by State Route 3. The roughly 1.4 acres property has been previously
developed with a single-family residence. We have shown the existing building and site layout
on the Site Sketch, Figure 2.
The site's topography consists of a relatively level area, less than 15 percent, in the area of the
existing single-family residence and in the area proposed of the new addition. Beyond the
existing residence to the north the slope trends up with slopes of 10 to 15 percent. The slope
increases in steepness as it descends south of the existing residence with gradients of about 20
to 30 percent. Localized steeper slopes of about 80 percent were observed about 100 feet
south of the proposed addition. The overall slope height was roughly 50 feet as measured
above the access road and proposed finish floor elevation of the new addition. We have shown
the slope profile on Cross Section A-A, Figure 3.
Vegetation in the developed potions of the site consists of lawn and landscaping. The slope
areas were vegetated with Douglas fir, brush, cedar, madrona, and large leaf maple.
PROPOSED DEVELOPMENT
As presently conceived, a new addition will be constructed along the west side of the existing
single-family residence. The structure will be of light wood frame construction with a footprint of
roughly 325 square feet. We have shown the proposed building area on the Site Sketch, Figure
2 and Cross Section, Figure 3.
FIELD INVESTIGATION
The site's subsurface conditions were explored on May 10, 2010 by excavating two test pits.
The test pits were extended down 3 to 5 feet below current site grades. The test pit locations
P.O. Box 637. 2453 Bethel Avenue • Port Orchard, Washington 98366
Phone: 1(800) 755-1282 Fax: (360) 876-1487
C.\Documents and SettingsM,lohnson\My DocumentsTroject Folder\7450 Payson Slope\Payson Slope Assessment.doc
Project No. 7450-10
May 24, 2010
Page No. 2
are shown on the Site Sketch, Figure 2. Further discussion of the test pit excavation is
provided in the following section.
Site Soil Conditions
In general, our test pits revealed dense to very dense glacial till below the new addition and
underlying slope area. The glacial till was encountered about one foot below present site
grades in the area of the new addition and about 4 feet below current site grades south of the
existing residence. The test pit locations are shown on the Site Sketch, Figure 2. For a more
detailed description of the subsurface investigation, please refer to Appendix A.
Groundwater
During our subsurface exploration, perched groundwater and standing water conditions were
not encountered. However, horizontal groundwater seepage may occur above the level of the
glacial till during the winter time rainy season.
AVAILABLE GEOLOGIC SOILS INFORMATION
The Washington Division of Geology and Earth Resource (WDGER), Geologic Map of
Washington — Northwest Quadrant, dated 2002, has mapped the site as Quanternary
sediments, dominantly glacial drift and includes alluvium. Glacial till consists of an unsorted,
unstratified, highly compacted mixture of clay, silt, sand, gravel and boulders deposited by
glacial ice.
DEPARTMENT OF ECOLOGY WATER WELL REPORT
A water well log located at the address of East 17991 HWY 3, Allyn WA, Mason County Parcel
Number: 122203490151, indicates a static groundwater level 63 feet below the approximate
level of the access road reflected on our Cross Section A-A, Figure 3. The property the well
was drilled on is located down slope southeast of the subject property. Based on a water well
report drilled near the property, we anticipate the glacial till extends 55 to 60 feet below our test
pit excavation. The water well log was from State of Washington, Water Well Reports drilled by
Davis Drilling dated April 1994.
SLOPE RECONNAISANCE
As part of our fieldwork, the slope areas comprising the areas both on an off the propoerty were
examined for indications of instability. Indications of slope instability include head scarps,
hummocky terrain, inconsistent patterns of vegetation, tension cracks, seepage zones and
course grain material overlaying silt and clay soils. At the time of our slope reconnaissance on
May 10, 2010, the slope areas south of the new addition appears stable.
HISTORICAL LANDSLIDE RESEARCH
A review of "Relative Slope Stability of Southern Hood Canal Area, WA, 1977" USGS
Miscellaneous Investigation Series indicates the area in and around the property has been
classified as Class 1, Class 2 and Class 3. Discussion of each class is provided in the following
and the Slope Stability Mapping for the site has been illustrated on Figure 4.
P.O. Box 637. 2453 Bethel Avenue • Port Orchard, Washington 98366
Phone: 1(800) 755-1282 Fax: (360) 876-1487
C\Documents and SettingsMJohnsonUy Documents\Project Folder\7450 Payson Slope\Payson Slope Assessment.doc
Project No. 7450-10
May 24, 2010
Page No. 3
Class 1: Areas believed to be stable, generally less than 15 percent, but may be greater locally
in areas too small to be shown at the map scale. Largely comprises rolling uplands underlain
by stable material such as glacial till, mantled in places by a thin layer of sandy gravel or other
permeable material; also includes flood plains, deltas, alluvial fans, and some beach deposits.
Class 1 areas immediately adjacent to steep slopes of class 3 areas may be threatened by
potential landsliding. Normal, proper engineering practices generally are adequate to insure
stability in these areas.
Class 2: Areas believed to be stable under normal conditions, but may become unstable if
disturbed by man activities, if slope is over steepened by erosion, or subjected to strong seismic
shacking. Slope generally steeper than 15 percent, but may be less in some areas of weak
geologic material. Includes area underlain by: well-drained sand and gravel, mostly on valley
sides that lack known slope failures; glacial retreat with steep slopes; and bedrock.
Class 3: Areas inferred to be unstable because slopes, generally greater than 15 percent, and
underlain by weak, unstable materials in which old or recently active landslides have occurred.
Includes areas of sand and gravel on top of impermeable silt and clay, mostly along steep
valley sides.
The "Relative Slope Stability of Southern Hood Canal Area, WA, 1977" indicates the area of
proposed development has been classified as Class 1 or Class 2. The areas designated as
Class 3 reside roughly 750 or more yards southwest of the proposed new addition.
UPSLOPE GEOMORPHOLOGY
According to Eric J. Schuster's, "Geologic Map of Washington State", the site and its
surrounding geologic nature are classified as Pleistocene Continental Glacial Drift (Qgd). The
unique geomorphology of this area shows signs of glacial scouring in generally a northeast-
southwest direction. These trending ridges and valleys were carved by the retreat of glacial ice
in the Pleistocene (approximately 10,000 to 12,000 years ago to the end of the Epoch). During
the retreat and melting of the glacial ice, the scoured areas and closed depressions were filled
with outwash material (alluvium). Alluvium consists of glacial fluvial sediments, such as sand
and gravel that are deposited near the terminus of the glacier in a size-sorted manner (fines up
sequence).
UPLAND WATER BODIES
The closest upland water body is Lake Anderson a distance of about '/z mile to the northwest.
In our opinion, based on the lake being up slope of the property, we do not anticipate the
proposed construction will influence this upland water body.
WETLANDS
The wetland mapping indicates Sherwood Creek is approximately 300 feet to the southwest and
saltwater shoreline resides 450 feet south of the proposed development. In our opinion,
surface runoff generated by the new addition, an impervious area of about 325 square feet (sf),
will be intercepted by drainage ditches upslope of the wetland areas by either State Route 3 or
East Sherwood Creek Road in the unlikely event any surface runoff from the proposed
development should ever occur. In our opinion, NLO does not anticipate that the proposed new
P.O. Box 637. 2453 Bethel Avenue • Port Orchard, Washington 98366
Phone: 1(800) 755-1282 Fax: (360) 876-1487
C\Documents and Settings\WJohnson\My Documents\Project Folder\7450 Payson Slope\Payson Slope Assessment doc
Project No. 7450-10
May 24, 2010
Page No. 4
addition will impact wetland areas located down slope. No other documented wetland areas are
noted in the general vicinity of the property.
CONCLUSIONS AND RECOMMONDATIONS
Following our review of Mason County Resource Ordinance, Ordinance Number 77-93, we
conclude that large scale sliding or deep-seated rotational failures resulting from the proposed
construction appears negligible. The overall global stability of the property under the present
site conditions appears good.
Based on the encountered glacial till soil conditions and the current distance the new addition is
from any steep slope area, in our opinion, an additional geotechnical engineering report will not
be required.
REPORT LIMITATIONS
This report has been prepared for the client regarding the subject project. Information
presented in this report has been collected and interpreted in a manner consistent with the level
of care and skill ordinarily exercised by members of the profession currently practicing under
similar conditions, and in accordance with sound and generally accepted principles consistent
with normal consulting practice. No other warranty, expressed or implied, including (but not
limited to) any warranty or merchantability or fitness for a particular use has been made.
In the event that change in the nature, design, or location of the proposed construction is made,
or any physical changes to the site occur, recommendations are not be considered valid unless
the changes are reviewed by NLO and conclusions of this report are modified or verified in
writing.
Any site involving sloping terrain has inherent risk of earth movement. As a result, the CLIENT
agrees to accept full responsibility for all risks associated with steep slopes. The CLIENT
acknowledges that this risk cannot be completely eliminated and that engineering and geologic
analysis is intended to reduce the inherent risk associated with slopes. No amount of
geotechnical engineering and geologic analysis can provide a guarantee of stable slopes.
Geotechnical engineering and geologic analysis are based heavily on subjective interpretation,
professional judgment, and opinion regarding the physical conditions at a specific site.
Subsurface conditions are only documented at those points where samples were taken and
interpolation and extrapolation is necessary between and around sample locations. Conditions
can vary between samples and can change over time due to natural processes and/or human
activity. Analyses and recommendations provided in this report are based in part upon the data
obtained from the subsurface explorations.
P.O. Box 637. 2453 Bethel Avenue • Port Orchard, Washington 98366
Phone: 1(800) 755-1282 Fax: (360) 876-1487
C Tocuments and Settings\WJohnson\My Documents\Project Folder\7450 Payson Slope\Payson Slope Assessment.doc
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Vicinity Map Developed From Department Of Ecology Water Well Log Information.
R. J,1 FIGURE 1
VICINITY MAP FOR. SCALE: NONE
A MR.STEVE PAYSON DATE: srzamtO
k-J N.L.0Ison&Associctes,inc. p m 101 EAST STEVES PLACE Engineering, Planning and Surveying a.�� fi` 3301WESTHIGHWAYI6 ORAWNG NUMBER
(,360) 876-2284
ss'ONAL�� ALLYN, WA PORT ORCHARD,WA 7450-10
24M Be"Avenue,P.O.Box 637,Port Orchard,WA 9. �� SHEET OF
_ EXISTG. RESIDENCE
LOT 2
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SCALE 0' REFERENCE
1 inch = 30 feet
P
SITE PLAN DEVELOPED FROM DRAWING PROVIDED BY CLEINT.
REVISIONS BY DATE A 3 Z FIGURE 2- SITE SKETCH FOR: Mr.STEVE PAYSON SCALE: AS 94OW
NO. DATE BY DESCRIPTION DESIGNED L.�j N.L.Olson&Associates,Inc. LOT B - SHORT PLAT#2456 3301 WEST HIGHWAY 16 DATE MAY 24,2010
DRAWN Engineering, Planning and Surveying CHECKED �o�''n a°e�`� 101 EAST STEVES PLACE, ALLYN, WA Port Orchard,WA 98367 JOB NUMBER
JtONAL7450-10
APPROVED (360) 876-2284 PARCEL#: 122203490362
H T 1 1
ACCEPTED 2453 Bethel Avenue,P.O.Bo:637,Port OrehcM,WA 98366
��
EXISTING BUILDING
10
PROPOS D ADDITION
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OBSERVED �`� GLACIAL T ILLGLACIAL TILT; o�
ao
Access Drive l
SR 3
20
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0 20 40 60 8o 100 120 140 163 180 200 220 240 260
SCALE
1 inch = 20 feet
(LOOKING WEST)
CROSS SECTION A-A
DURING OUR RECONNAISANCE,A LIMITED SLOPE SURVEY WAS PERFORMED UTILIZING A HAND HELD
(SUNTO TYPE PM-5/360C)TO ESTIMATE SLOPE GRADIENTS AND A 300 FOOT FIBERGLASS TAPE WAS
UTILIZED FOR SLOPE DISTANCE MEASUREMENTS. THE SURVEY SHOULD BE CONSIDERED
ACCURATE ONLY TO THE DEGREE IMPLIED AND METHODS USED.
R. JpH^,_
FIGURE 3- CROSS SECTION A-A FOR:
BY DATE SCALE: AS 4H 201
REVISIONS ,� Mr.STEVE PAYSON
DESIGNED Ike DATE:NAY 1l, ?OIO
NO. DATE BY oEscRlanory L�J N.L.Olson&Associates,InC. LOT B - SHORT PLAT 2456 3301 WEST HIGHWAY 16
DRAWN '+Md° � JOB NUMBER
Engineering, Planning and Surveying �
CHECKED „oH,��� 101 EAST STEVES PLACE, ALLYN, WA Port Orchard,WA 98367 7450-10
APPROVED (360) 876-2284 PARCEL#: 122203490362
ACCEPTED 2453 Bethel Avenue,P.O.Box 637,Port Orchard,WA 96366 - SHEET. / OF /
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APPENDIX A
The site's subsurface conditions were explored on May 10, 2010 by excavating two test pits.
The test pits were extended down 3 to 5 feet below current site grades. In general, our test pit
revealed the area between the slope and proposed new addition was underlain by dense to
very dense glacial till. The depth of the till was about one foot below the new addition and about
4 feet below current site grades south of the residence near the top portion of the slope. The
test pit location is shown on the Site Sketch, Figure 2. The test pit logs have been included in
this appendix.
The subsurface exploration logs and related information depicts conditions only at the specific
locations and at the particular time designated on the logs. The passage of time may result in a
change of subsurface conditions at these exploration locations. Subsurface conditions at other
locations may differ from conditions occurring at the exploration locations. The nature and
extent of variations of subsurface conditions between explorations are not known. If variations
appear during additional explorations or construction, re-evaluation of recommendations in this
report may be necessary.
P.O. Box 637. 2453 Bethel Avenue • Port Orchard, Washington 98366
Phone: 1(800) 755-1282 Fax: (360) 876-1487
C Tocuments and Settings\WJohnson\My Documents\Project FclderN7450 Payson Slope\Payson Slope Assessment.doc
A Test Pit Log
k-`JN.L.Olson&Associates,Inc.
Engineering,Planning and Surveying Mr. STEVE PAYSON
2453 BETHEL AVENUE 3301 WEST HIGHWAY 16
P.O.BOX 637 PORT ORCHARD, WA
PORT ORCHARD,WASHINGTON 98366-0637
Job Number Logged By: Subsurface Exploration Ground Surface Elevation Test Pit Number Page
7450-10 WRJ Sta rt Date.5/10/2010 End
s/10/2070 80 TP-1 1 of 1 Date:
Surface
Conditions:
General
Notes
n$ LISCS t Moisture
Sample Collected O E SYMBOL o Content Gravel Parking Area
u7 p (%)
SM Brownish Gray Silty SAND with gravel and cobbles trace boulders, dense,
1 moist,
- Grades to gray at one (1) foot and becomes very dense-Glacial Till
SM 2-
3—
End of Test Pit 3 ft bgs
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Contractor Operators Name Sampling Method Drawn By Date Test Pit Completion
Sundance Steve Payson Grab WRJ 5/26/2010 Monitoring Well
Equipment Groundwater Elevation Checked By: Date Piezometer
Small Trackhoe None WRJ ® Abanonded and backfilled
LOCATION: Revision By: Date
101 EAST STEVES PLACE ERC
El
ALLYN,WA
A Test Pit Log
k `JN.L.Olson&Associates,Inc.
• Engineering,Planning and Surveying Mr. STEVE PAYSON
2453 BETHEL AVENUE 3301 WEST HIGHWAY 16
P.O.BOX 637 PORT ORCHARD, WA
PORT ORCHARD,WASHINGTON 98366-0637
Job Number Logged By Subsurface Exploration Ground Surface Elevation Test Pit Number Page
Da
7450-10 WRJ Sta5110/2010 End5/10/2010 `70 TP-2 1 of 1
Surface
Conditions
General
Notes
USCS t Moisture
Sample Collected - SYMBOL d Content Gravel Parking Area
Dark Brownish Gray Silty SAND with gravel and cobbles, medium dense,
SM 1 moist,
2
3
4 S M — — — — — — — — — — — — —
- Grades to gray at four(4)feet and becomes very dense- Glacial Till
5
End of Test Pit 5 ft bgs
6
7
8
9
10
11
12
13
14
15
16
17
18
Contractor Operators Name Sampling Method Drawn By Date Test Pit Completion
Sundance Steve Payson Grab WRJ 5/26/2010 ❑ Monitoring Well
Equipment Groundwater Elevation Checked By: Date ❑ Piezomeler
Small Trackhoe None WRJ ® Abanonded and backfilled
LOCATION. Revision By Date ❑
101 EAST STEVES PLACE ERIC ❑
ALLYN,WA ❑
t
Mason County Review Checklist
For a Geological Assessment
Instructions:
This checklist is intended to assist Staff in the review of a Geological Assessment. The
Assessment is reviewed for completeness with respect to the Resource Ordinance. If an item is
found to be not applicable, the report should explain the basis for the conclusion. The
Assessment is also reviewed for clarity and consistency. If the drawings, discussion, or
recommendations are not understandable, they should be clarified. If they do not appear
internally consistent or consistent with the application or observations on site, this needs to be
corrected or explained. If resolution is not achieved with the author, staff should refer the case to
the Planning Manager or Director.
Applicant's Name: f a4A 4—
Permit# �-D qv W - o o 236 Parcel # 22 Zo
moo - ooOl
Dates)of the ocument(s) reviewed:
(1) A discussion of geologic conditions in the general vicinity of the
proposed development,with geologic unit designation based
on referenSgd maps.
OK?___Z Comment:
(2) (a)A discy�sion of the groundwater conditions at the site,
OK? { Comment:
(b) A discussion of the estimated depth to water
OK?_Comment:
(c) A discu sion of the quantity of surface seepage
OK? Comment:
(d) A discussion of the upslope geomorphology
OK?_,eL'Comment:
(e) A disc ssion of location of upland waterbodies and wetlands.
OK? Comment:
(3) The appro Imate depth to hard or dense competent soil, e.g. glacial till or outwash sand.
OK? Comment:
(4) A discussion of any geomorphic expression of past slope instability(presence of
hummocky ground or ground cracks, terraced topography indicative of landslide block
movement owed or arched trees indicating downslope movement, etc.).
OK?Comment:
(5) A discussion of the history of landslide activity in the vicinity, as available in the
referenced m ps and records.
OK?�omment:
(6) An op i n on whether the proposed development is within the landslide hazard area or
its associated buffer or setback and the potential for landslide activity at the site in light of
the prn osed,development.
OK? Comment: Wila-
(7) A reco endation by the preparer whether a Geotechnical Report should be required to
further evaluate site conditions and the pr posed development of the subject property.
OK? H Comment: (/l pIA-i�
(8) If the prbsbnce of a hazard is dete mined within 300 feet of the proposed development,
then the following are delineated on a geologic map/site map:
(a) the area of the proposed dev lop ent' I
OK? Comment: !v
Page 1 of 2 Form Effective June 2008
(b) the boundaries of the landslide azard area top, both sides and toe),
OK? Comment: (_ /V
(c) the associated buffers_(p, both s'flees,,pnd toe `
OK? Comment-.
(d) building or other setbacks (t p, bo)h sid s, anc�to�)
OK? Comment: �LJ
(9) A site map drawn to scale showing' e property boundaries, scale, north arrow, and the
location and nature of sting and oposed development on the site.
OK? Comment:
Are the.Document(s)signed and stamped?
Type and #of License:
If not approved, what is the next action/recommendation for further ction? I ��
Reviewed by on
Time spent in review:
SECOND REVIEW/UPDATE:
Reviewed by on `
Time spent in second review:
THIRD REVIEW/UPDATE:
Reviewed by on
Time spent in third review:
Disclaimer: Mason County does not certify the quality of the work done in this Geological
Assessment
Page 2 of 2 Form Effective June 2008
APPENDIX B
Mason County Department of Community Development
Submittal Checklist for a Geological Assessment
Instructions:
This checklist must be submitted with a Geological Assessment and completed, signed, and stamped by
the licensed professional(s)who prepared the Geological Assessment for review by Mason County
pursuant to the Mason County Resource Ordinance. If an item found to be not applicable, the report
should explain the basis for the conclusion.
Applicant/Owner: Mr. Steve Payson Parcel # 122203490362
Site Address 101 East Steves Place, Allyn, WA
(1) A discussion of geologic conditions in the general vicinity of the proposed development, with
geologic unit designation based on referenced maps.
Located on page(s) 2 & 3
(2) (a) A discussion of the ground water conditions at the site.
Located on page(s) 2
(b) A discussion of the estimate depth to water
Located on page(s) 2
(c) A discussion of the quantity of surface seepage
Located on page(s) 2
(d) A discussion of the upslope geomorphology
Located on page(s)3
(e) A discussion of location of upland waterbodies and wetlands.
Located on page(s) 3
(3) The approximate depth to hard or dense competent soil, e.g. glacial till or outwash sand.
Located on page(s) 9-
(4) A discussion of any geomorphic expression of past slope instability(presence of hummocky
ground or ground cracks, terraced topography indicative of landslide block movement, bowed or
arched trees indicating downslope movement, etc.).
Located on page(s) 2
(5) A discussion of the history of landslide activity in the vicinity, as available in the referenced maps
and records.
Located on page(s) 2
(6) An opinion on whether the proposed development is within the landslide hazard area or its
associated buffer or setback and the potential for landslide activity at the site in light of the
proposed development.
Located on page(s) 4
(7) A recommendation by the preparer whether a Geotechnical Report should be required to further
evaluate site conditions and the proposed development of the subject property.
Located on page(s) 4
(8) If the presence of a hazard is determined within 300 feet of the proposed development, then the
following are delineated on a geologic map/site map:
(a) The area of the proposed development,
Located on Map(s) N/A— No Hazards Noted
(b) The boundaries of the landslide hazard area (top, both sides, and toe),
Located on Map(s) N/A— No Hazards Noted
(c.) The associated buffers (top, both sides, and toe)
Located on Map(s) N/A— No Hazards Noted
(c) Building or other setbacks (top, both sides, and toe).
Located on Map(s) N/A— No Hazards Noted
(9) A site map drawn to scale showing the property boundaries, scale, north arrow, and the location
and nature of existing and proposed development on the site.
Located on Map(s) See Figure 2
P.O. Box 637. 2453 Bethel Avenue • Port Orchard,Washington 98366
Phone: 1(800) 755-1282 Fax: (360) 876-1487
CADocuments and Settings\WJohnson\My Documents\Project Folder\7450 Payson Slope\Payson Slope Assessment.doc