HomeMy WebLinkAboutDDR2013-00047 and GEO2013-00025 - DDR Reports - 7/5/2013 vV
Mason Cou ty Permit Center Use:
MASON COUNTY
DEPARTMENT OF COMMUNITY DEVELOPMENT DDR 7_n13
411 N. Fifth Street/P.O. Box 186, Shelton WA 98584
360.427.9670 ext.352 Date Revd
Request for
Administrative Variance for Reduction in the Required Setbacks ($115.00)
For administrative review, the minimum variance on a setback request is 5 feet from the side yard lot
lines and 10 feet for front and rear lot lines or any access easement. Request for further reduction
requires a standard variance. Setbacks are measured from the furthest projection of the structure,
including roof eaves.
Applicant/Owners: Allen W. and Lynn M. Carter
Mailing Address: PO Box 234
City: Tahuya State: WA Zip: 98588
Telephone: 206 909 7568
Email: carterllib@hotmail.com
If this reduction is tied to a building permit, please give permit case number.
BLD
Parcel Number(s):
32224-50-00029 Zoning Rural Res. 5
Site Address: 10871 NE North Shore Road
Requested setback variance:
5 ft. ❑ Front ❑ Rear )UCSide
ft ❑ Front ❑ Rear ❑ Side
ft. ❑ Front ❑ Rear ❑ Side
ft ❑ Front ❑ Rear ❑ Side
Front Setbacks—From access easements and road right ofways. Minimum 10 feet.
Rear Setbacks—From the rear property line. Minimum 10 feet.
Side Setbacks—From the side property line. Minimum 5 feet except for certain shoreline designations.
An illustrated site plan is required.
Your site plan must show the following: north arrow, abutting street or easements, set backs to all
property lines and existing buildings, slopes, surface water, wetlands, critical areas, septic, well and
driveway. Show all proposed new development.
CACommunity DevelopmentlPACAVARIANCESVAdmin Vnriance.doc Edited on 7/16/10
FRONT AND OR REAR YARD REDUCTION REQUESTS:
For existing lots of record as of March 5, 2002;
You must meet one of the following:
2) One of the following exists on the lot(check all that apply):
❑ a) steep slopes, wetlands, or streams present;
❑ b) soils that restrict building or septic development;
❑ c) lot width at the front yard line of no more than 50 feet;
❑ d) lot size of no more than one-fourth acre;
❑ e) existing improvements of buildings, septic systems, and well areas.
SIDE YARD REDUCTION REQUESTS:
For existing lots of record as of March 5, 2002;
You must meet one of the following:
2) One of the following exists on the lot(check all that apply):
30 a) steep slopes, wetlands, or streams present;
❑ b) soils that restrict building or septic development;
❑ c) lot width at the front yard line of no more than 50 feet;
d) lot size of no more than one-half acre;
>0 e) existing improvements of buildings, septic systems, and well areas.
Explain how these circumstances preclude a reasonable development proposal from meeting the
setback standard for Rural Residential 2.5, 5, 10, or 20 zones.
We are expanding our current residence, and the location of the existing portion of the house is slightly skewed
to the lot line. We propose to cover and extend the existing deck but to do so in a reasonable manner will
move the corner of the deck and roof overhang from about 7 feet from the property line to about 5 1/2 from
the property line.
�wne Agent(please indicate)
Signature Date
Official Use Only /
Approved by: lG�Z,YLti Date C)Q /G
Denied by: Date
Reason for denial:
IlACommonity DevelopmentVPACAVARIANCESVAdmin Variance.doc Edited on 7/16/10
MASON COUNTY
DEPARTMENT OF COMMUNITY DEVELOPMENT
Planning Division
FP14 P O Box 279, Shelton, WA 98584
(360)427-9670
Geotechnical Assessment Review Acceptance Letter
August 09, 2013
ALLEN CARTER
P O BOX 234
TAHUYA WA 98588
Case No.: GE02013-00025
Parcel No.: 322245000029
Proiect Description: RESIDENCE
The Geotechnical Assessment for ALLEN CARTER has been received and reviewed by the
Planning Department. The assessment was prepared by Allaen Carter dated 5/22/2013.
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,
Allan Borden
Land Use Planner
Mason County Planning Department
Comments:
81912013 Page 1 of 1 GE02013-00025
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:
Permit#: 101a�.�V L��11 1/7 Parcel#'s: 31k� '50 — oQU? 4 — POO
Date(s) of the Document(s) reviewed:
1. A discussion of geologic conditions in the general vicinity of the proposed development, with geologic unit
designation based on referenced maps.
OK?_t Comment:
2. (a) A discussion of the ground water conditions at the site,
OK? 11—/ Comment:
(b) A discussionn of the estimated depth to water
OK? ✓ Comment:
(c) A discussio of the quantity of surface seepage
OK? Comment:
(d) A discussio f the upslope geomorphology
C. Comment:
(e) A discussio of location of upland waterbodies and wetlands.
OK? Comment:
3. The approximate 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, bowed or arched trees indicating
downslope movem nt, etc.).
OK? Comment:
5. A discussion of the history of landslide activity in the vicinity, as available in the referenced maps and records.
OK? Comment: ��
6. An opinion on whether the proposed development is within the landslide hazard area or its associated buffer or
setback and the tential for landslide activity�t the site in light of the proposed development.
OK? Il/l Comment: _�:7
7. A recommendation by the preparer whether a Geotechnical Report should be required to further evaluate site
conditions and the p posed development of the subject property.
OK? Comment: ✓2(
Page 1 of 2 Form Effective June 2008
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,
OK? Comment:
(b) the boundaries of the landslide hazard area (top, both sides, and toe),
OK? Comment:
(c) the associated buffers (top, both sides, and toe)
OK? Comment:
(d) building or other setbacks (top, both sides, and toe).
OK? Comment:
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.
OK? Comment:
Are the Documents signed and stamped? By whom? "
License#: License type:
FIRST REVIEW —� � R
If not approved, what is the next action/recommendation for further action?
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
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Geotechnical Assessment
10871 and 10891 NE Northshore Road
Mason County Washington
Parcel Numbers 32224-50-00029 and 32224-50-00085
N47° 22.730'- W 123°00.818'
May 22, 2013
ERA°
sf�NAL
A. W. (Bill) Carter P.E. PO Box 234 Ph. 206 909 7568
Tahuya WA98588
Geotechnical Assessment
10871 and 10891 NE Northshore Road
Mason County Washington
Parcel Numbers 32224-50-00029 and 32224-50-00085
N47°22.730'- W123°00,818'
Introduction
This report summarizes the results of a geotechnical investigation for the construction of an addition to
the single family residence located at 10871 NE Northshore Road,approximately 11 miles west of Belfair
WA. The location of the site is shown relative to the surrounding area on the Vicinity Map, Figure 1.
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� IOB)1 N1�9l N.nIM1SM.., % MV C]EN -
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Figure 1. Vicinity Map
This report is based on field investigations of the proposed site, and review of available public
documents that provide basic soils and geological data for the area. The propose project will expand the
existing single family residence expanding by approximately 30 feet westward,with a small addition to
fully roof over the exiting deck that is currently partially covered at the easterly end of the existing
house. The existing wood frame house was constructed in about 1968 and has a concrete foundation.
The septic tank is east of the existing house (was likely installed at the time of the original construction)
and will not be disturbed by the construction. The leach field was constructed in 1995 and is located on
the north side of the Northshore Road and will also not be disturbed.
A.W. (Bill) Carter P.E. PO Box 234 Ph. 206 909 7568
Tahuya WA 98588
1
The portion of the property that composes the building site is currently landscaped primarily with lawn
and slopes to the south with a maximum grade of approximately 20%and an average grade of
approximately 12%. 15 to 20 feet north of the building site an existing rockery that retains a driveway
embankment that rises from approximately 20 feet along the Northshore Road embankment. This
rockery varies in steepness but is generally at a %to 1 slope. 27 to 35 south of the proposed
construction there is an existing concrete seawall that rises 3 to 4 feet above the beach level and
extends along the frontage of both parcels. Modification of the existing driveway,and seawall is not
proposed.
The purpose of this report is to comply with the Mason County Critical area ordinance and evaluate the
surface and subsurface conditions at the site as a basis for providing geotechnical recommendation and
design criteria for the project. This report will:
1. Review the available geotechnical, hydro-geologic and geotechnical data for the site.
2. Conduct a geotechnical reconnaissance of the site area and surrounding vicinity.
3. Investigate shallow subsurface conditions at the site by observing the exposed soils and by
excavating test holes on the site.
4. Evaluate the landside and erosion hazards at the site per the Mason County Critical area
Ordinance regulation.
5. Provide geotechnical recommendation for site grading,foundations excavations, subgrade
preparation, back fill placement criteria, temporary and permanent drainage and erosion
control measure.
Throughout this report the term site, or construction site refers to the actual area to be disturbed by
construction and the tem parcel refers to the entire property in the above noted parcel numbers.
SITE CONDITIONS
Surface Conditions
The proposed building site is located in an area of moderate residential development in the Puget Sound
glacial upland along the north shore of the Hood Canal. The site has a southern exposure and is located
between the Northshore Road and Hood Canal. A reconnaissance of the site was conducted in April
2013 for the purposes of this report. Parcel elevations range from Sea level to approximately 40 feet.
The construction site within the parcel ranges from approximately 10 feet to 20 feet.
The building area is currently landscaped primarily with lawn, with a small rose bed next to the existing
house.
At this time there is no evidence of active surface erosion, or deep-seated slope instability. There is
evidence of past settlement at the top of the driveway near the Northshore Road, but this has been
stable for the past 11 years and was probably occurred shortly after initial construction as a result of
poorly compacted fill. On the north side of the Northshore Road an existing''%: 1 exposed slope
approximately 20 feet high has stood for 11 years with no erosion or sloughing and provides an excellent
2
view of the native soils. Adjacent parcels both east and west of this location steeper near vertical cut
slope have stood for similar time periods with only minor erosion occurring.
Surface and Ground Water
Surface flows due to heavy rain fall are rare and occur only as minor sheet flows during the heaviest
storms. There is one spring in the side of the Northshore Road fill approximately 25 feet west of the
easterly property line that feeds an existing cistern. The spring is about 15 feet above the footing level
and 45 feet north of the existing house. The flow of about 3 gallons per minute is conveyed to the Hood
through an existing underground drainage system.Two minor seasonal springs or seeps are located
along the foot of the driveway fill to the west of the building site. Both drain to the Hood Canal through
underground piping. No other springs or weeps are evident in the slope where the new foundation is to
be located and no ground water was observed in test holes. Footing drains from the existing foundation
produce seasonal flows consistent with what would be expected from the discharge of peculating rain
water.
No upland water body or wetland is located within 300 feet of the parcel.
Figure 2—Construction Site Figure 3—Construction Site to Left of Ex. Str.
Site Geology
The site is general situated within the Puget Sound glacial upland. The topography, as well as the
surficial and shallow subsurface soils in the area are the result of the most recent Vashon stage of the
Fraser glaciation occurred between 10,000 and 12,000 years ago, and weathering and erosion that has
occurred since. A description of the surficial soils is included in the "Site Soils" section of this report. In
general the soils are composed of glacial advance outwash and glacial drift.
3
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P.�
Figure 4—Site:Aerial View
Site Soils
The Soil Survey of Mason County, USDA Soil Conservation Service(1960)'has mapped the site soils as an
Everett gravelly sandy loam, 15 to 30 percent slopes (Ek). The Everett soils typically formed on terraces
and outwash plains formed in the glacial outwash stage of the most recent Fraser glaciation.
Permeability is rapid (up to 20 inches per hour)with a high rate of water transmission. These soils are
further characterized as having medium runoff potential and moderate water erosion potential. Shrink-
swell potential is low due to the low organic content. No active erosion or slope disturbances in the site
have been observed.
The Geologic Map of Washington—Northwest Quadrant(2002) has mapped the site geology as
advanced outwash deposits (Qga) of continental glacial origin (see Figure 5). The report reads:
Advanced outwash—Glaciofluvial sand and gravel and locustrine clay, silt, and sand deposited
during the advance of glaciers;sandy units commonly thick, well sorted and fine grained, with
interlayered coarser sand, gravel, and cobbles;locally contains non-glacial sediments and
deposits mapped as transitional between glacial and non-glacial. Includes the Colvos and
Esperance Sand members of the Vashon Drift and part of the Vashon Drift undivided.
4
- Qga,
i f 'j t ---Qga Iv' oaf
Oga� i ?
o-+
tia
QgO
Oga y C
Qapo Qga
ca
C
Figure 5 - Portion of Geologic Map of Washington
Visual inspection of soils on the site show they tend towards the more gravely range of the above
description and are consistent from the ground surface to the proposed foundation elevation which
ranges from 2 to 8 feet below the existing grade.
Subsurface Investigation
Subsurface conditions at the site were evaluated by observing in existing exposed slopes, excavations on
adjacent parcels, and by advancing two hand dug test holes to the proposed foundations elevation.
Generally consistent dense well graded sandy, silt, gravels were encountered at all levels. While no tests
were conducted, experience would indicate that soil bearing values well in excess of 2000 lbs./sq.ft. can
be expected. Ground water was not encountered in either test hole.
In general undisturbed dense Everett gravely sandy loam was observed throughout the site and down to
the proposed foundation level (2 to 8 feet below existing grade). Ground water was not observed or
encountered except at elevations above and away from the proposed building site. Based on the site
topography, and the nature observed soils it is unlikely the significant ground water will be encountered
during excavation of the proposed foundation.
Slope Stability
The Relative Slope Stability of the Southern Hood Canal Area, Washington(1977)shows the site area as
Class 2, but it is very close to a Class 3 area. Class 2 areas are described as follows:
Areas believed to be stable under normal conditions, but may become unstable if disturbed by
man's activities, if slope is over steepened by erosion, or if subjected to strong seismic shaking.
Slopes generally steeper than 15 percent but may be less in some areas of weak geologic
5
materials. Includes areas underlain by: well-drained sand and gravels, mostly on valley sides
that lack known slope failures; glacial till with steep slopes,and bedrock.
While the Relative Slope Stability of the Southern Hood Canal Area, Washington (1977)describes Class 3
as:
Areas inferred to be unstable because slopes, generally greater than 15 percent are 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 valleys sides.
The near surface soils are in a dense to very dense condition except at the ground surface. The surficial
soils are general in a medium dense condition due to landscaping activities. In general,the undisturbed
native soils of the site consist of a mixture of variable amounts of sand, silt, and gravel. These soil
materials are in a dense condition except where disturbed by weathering activity. These soils are
general stable relative to deep seated failure. No evidence of deep seated landslide activity or
significant erosion was observed at the site or for several hundred feet in all directions.
Weathering, erosion and the resultant sloughing and shallow land sliding are natural processes that can
affect steep slope areas. Instability of this nature is typically confined to the upper weathered or
disturbed zone which has been disturbed and has a lower strength. Sloughing was not observed on this
parcel or adjacent parcels. Slopes in excess of%to 1 have stood without soughing or significant erosion
for over 10 years on this parcel and adjacent parcels.
The nearest known slide is located approximately% mile to the west along the Northshore Road. The
slide mainly involved fill material placed for the construction of the Northshore Road and some
underlying native soils. This location had long been the site of settlement in the Northshore Road grade
and slides have occurred on more than one occasion. Exposed native soils in this area contain a much
higher percentage of clays and fine material and are substantially different than at the proposed
building site.
CONCLUSIONS AND RECOMMENDATONS
General
Based on the results of my site reconnaissance, subsurface observations, and my experience in the area,
it is my opinion that the site is suitable for the proposed residential expansion. The slopes are stable
relative to deep seated instability and will not be affected by the proposed construction. The proposed
structure and excavation will not undermine adjacent structures. Proper drainage control measures will
easily control the potential for erosion in this area and improve slope stability. Proper construction
techniques will overcome any potential for landslides and should not pose a threat to existing
structures. The project should have no significant environmental impacts.
In general,the Everett soils observed at the site are suitable for use a structural fill materials. Saturated
soil conditions are not associated with these soils during or following extended periods of rainfall.
However, to reduce grading time and construction cost, I recommend that earthwork be undertaken
6
during favorable weather conditions and any excavated material intended for backfill be protected from
rainfall while in stockpile.
Conventional spread footings will be satisfactory for this project. I recommend that roof and footing
drains be installed for the structure and positive drainage be provided to a convenient outfall away from
the foundations. Vapor barrier is recommended for use under the basement slab.
Classification
The Mason County Critical Areas Ordinance (17.01.100) defines a landslide hazard area as"any area
with a slope of forty percent or steeper and with a vertical relief of ten or more feet except areas
composed of consolidated rock." Onsite slopes are in excess of 80 percent with a toe to crest average
grade of about 55 percent and the vertical relief is greater than 10 feet. Based on this the site meets the
technical criteria of a landslide hazard.
Slope Stability
Based on my field observations, explorations, and my experience with soils of the type encountered, I
conclude that although portions of the slopes on the parcel exceed 80 percent,the slopes are stable
relative to deep seated failure in their current configuration. Surface soils down to the foundation level
are expected to be Everett gravely sandy loam (EJ which is relative stable even when cut steeper than a
1:1 slope. As noted in the section on Site Preparation and Excavation and cuts in excess of 4 feet should
be sloped at a 1:1 slope.
Building Setback
Excavation for the project will be a maximum of 12 feet deep. Provided that grading is conducted as
recommended herein and surface water flows are controlled while the excavation is open, no slope
stability problems are anticipated. I recommend that any organic soils or soils containing deleterious
material be excavated and removed from the site if encountered. Erosion control measures should be
implemented as described late in this report. Construction of the basement foundation and retaining
walls with both footing and roof drains should increase the long term stability.
A more detailed Geotechnical report is not recommended for this project.
Seismic-Liquefaction Hazards
According to the Seismic Zone Map of the United States contained in the 2003 International Building
Code (IBC),the project site is located where the maximum spectral response acceleration is 45 percent
of gravity(g).
Based on the surface and subsurface conditions observed at the site, I interpret the site conditions to
correspond to a seismic Soil Profile Type C,for Very Dense Soil, as defined by Table 1615.1.1 (IBC). This
is based on probing with a %2 inch diameter steel probe rod. Soil conditions (Everett gravely sandy loam
7
(E,)was observed from the surface to the foundation elevation and surface conditions should represent
conditions at the foundation level.
I conclude that the site soils are only mildly susceptible to liquefaction. The near surface soils are in a
dense condition with cemented glacial till at shallow depths. Shaking of the already dense soil is not
likely to produce a denser configuration and subsequent excess pore water pressures should not
develop during a seismic event.
Erosion Control
The potential for erosion hazard of the site is not a limiting geological factor for the proposed
development. Removal of natural vegetation should be minimized and limited to active construction
areas. During construction control of surface water through the use straw matting on exposed soils is
advised. Routing of surface flows through the grasses remaining on the site should be sufficient to allow
for infiltrations and removal of most fine sediment. All disturbed areas should be seeded as soon as
practical.
Site Preparation and Excavation
All areas to be excavated should be cleared of all deleterious matter. Based on current conditions this
should only involve removal of existing sod to a depth of about 4 inches. This material should be
removed from the site or if suitable stockpiled for future landscaping.
Excavation should be done during expected dry weather, and any material retained for backfill covered
to prevent saturation. The excavated site should be inspected for and unsuitable materials at the
foundations level, and any found removed and the backfill compacted using a vibratory shoe other
acceptable means.
Temporary excavated slopes higher than 4 feet should be laid back on a slope of 1:1.
Structural Fill
All structural fill should be placed in horizontal lifts of approximately 6 inches and compacted to a firm
unyielding condition. Structural fill may be approved excavated material or commercially available well
graded backfill not containing more than 5% by weight passing a No. 200 sieve. All areas around drains
and along foundation wall to within 1 foot of final grade should be backfilled with approved open
graded pea gravel.
Foundations
Conventional footings complying with local building codes will be sufficient for this project. As noted
above all footing excavations should be inspected to ensure they are on firm competent soils. Footings
can be designed using a bearing value of 2000 PSF (pounds per square foot)for combined dead and live
load. The allowable bearing values may be increased by up to one-third for transient loads such as
seismic loads.
8
Lateral loads may be resisted by fiction on the bases of footings and floor slabs and as passive pressure
on the sides of the footings. I recommend that an allowable coefficient of friction of 0.40 be used to
calculate friction between the concrete and the underlying soil. Passive pressure may be determined
using an allowable fluid density of 300 PF (pounds per cubic foot).
Settlement of footings can be expected to be less than one inch.
Slab Floor Support
Slabs on grade should be supported on native or compacted native soils. If excessive water is
encountered I recommend a 6 inch layer of pea gravel under the concrete with positive drainage to
convey the water to a suitable outfall. A synthetic vapor barrier covered by a thin protective layer of
sand directly under the concrete may be used to further control the migration of moisture through the
slab.
Site Drainage
It is recommended that all native or paved surfaces be sloped away from the foundation. Down spouts
may be discharged on splash blocks except where slopes are less 2%or where surface water would
interfere with normal use of the property.
Foundations drains should be installed around the new foundation at the footing level and drains from
the existing foundation should be cleaned and tied into the new system.
Limitations
This report was prepared for the expansion of the single family residence located and the noted address
and is for the use of the design team for the purpose of designing the project. The data used in
preparing this report may be provided to prospective bidders. This report, its conclusions and
interpretations are based on data from other and site inspections. It should not be construed as a
warranty of subsurface conditions.
Add site map. Show toe hazard area as bottom of DW and top as Northshore road. Show a second area
above the north shore road.
9
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 Allen W. and Lynn M. Carter Parcel# 32224-50-00029 &32224-50-00085
Site Address 10871 and 10891 NE Northshore Road, Belfair WA 98528
(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) 3-6
(2) (a)A discussion of the ground water conditions at the site,
Located on page(s) 3
(b) A discussion of the estimated depth to water
Located on page(s) 3
(c) A discussion of the quantity of surface seepage
Located on page(s) 3
(d) A discussion of the upslope geomorphology
Located on page(s) 3-6
(a) 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) 5& 6
(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) 6
(5) A discussion of the history of landslide activity in the vicinity, as available in the
referenced maps and records.
Located on page(s) 5&6
(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) 6 &7
(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.
Page 1 of 2 Form Effective June 2008
Located on page(s) 7
(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)
(b) the boundaries of the landslide hazard area (top, both sides, and toe),
Located on Map(s)
(c) the associated buffers (top, both sides, and toe)
Located on Map(s)
(d) building or other setbacks(top, both sides, and toe).
Located on Map(s)
(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)
Allen W. Carter
I, hereby certify under
penalty of perjury that I am a civil engineer licensed in the State of Washington with specialized
knowledge of geotechnical/geological engineering or a geologist or engineering geologist
licensed in the State of Washington with special knowledge of the local conditions. I also certify
that the Geological Assessment, dated May 22, 2003 and entitled Geotechnical Assessment-
10871 and 10891 NE Northshore Road meets all the requirements of the
Mason County Resource Ordinance, Landslide Hazard Section, is complete and true, that the
assessment demonstrates conclusively that the risks posed by the landslide hazard can be
mitigated through the included geotechnical design recommendations, and that all hazards are
mitigated in such a manner as to prevent harm to property and public health and safety.
(Signature and Stamp)
W. C�
14018
S7ONALG
Disclaimer: Mason County does not certify the quality of the work done in this Geological
Assessment.
Page 2 of 2 Form Effective June 2008