HomeMy WebLinkAboutGEO2024-00043 Evaluation FPA - GEO Geological Review - 3/28/2024 �CC) gta� - 00 CA
ZipperGeo
Geoprofessional Consultants
ZGA Project No. 2787.07.1
March 28, 2024
Manke Family Resources, LP
826 Fairmont Avenue
Shelton, Washington 98584
Attn: Mr. Matt Manke
Mr. Kellen Manke
Subject: Forest Practice Engineering Geology Evaluation
Johns Prairie Proposed Harvest Unit 1
SE%509,T20N, R03W W.M.
MCTPN 320090902000
Mason County,Washington 98584
Dear Mr. Manke:
In accordance with your request and authorization, Zipper Geo Associates, LLC (ZGA) has completed a
forest practice engineering evaluation for a clear cut harvest in the vicinity of proposed Harvest Unit 1
(HU1) at the Johns Prairie sand and gravel surface mine project site.The purpose of this evaluation was
to identify unstable landforms as defined by the Forest Practices Board (WAC 222-16-050 (1)(d)(i)), and
to evaluate:
1. The likelihood that the proposed forest practices will cause movement on potentially unstable
slopes or landforms, or contribute to further movement of a potentially unstable slope or
landform;
2. The likelihood of delivery of sediment or debris to public resources, or in a manner that would
threaten public safety; and
3. Possible mitigation for the identified hazards and risks.
Our services included a review of pertinent geologic maps, the project's mine reclamation plan, previous
geologic and hydrogeologic investigations by others, LiDAR imagery, aerial photographs, a surface
reconnaissance, and preparation of this report. Our scope of services did not include a subsurface
investigation.
This report is an instrument of service and has been prepared for the exclusive use of Manke Family
Resources, LP, in accordance with generally accepted engineering geology practice for specific application
to this project and site location. No warranty,express or implied, is made.Verbal authorization to proceed
was provided by Mr. Matt Manke.
19019 36'h Ave West, Suite E I Lynnwood, WA 98036 1 Phone: 425.582.9928 1 zippergeo.com
Forest Practice Engineering Geology Evaluation Proposed Johns Prairie Harvest Unit 1 ZipperGeo
ZGA Project No. 2787.07.1
Geoprofessional Consultants
March 28, 2024
SITE LOCATION AND PROJECT UNDERSTANDING
The approximate location of the HU1 project area is indicated on Figure 1, Vicinity Map. The project site
is located at the Manke Family Resources Johns Prairie sand and gravel surface mine in the southeast
quarter of Section 09, Township 20 North, Range 03 West, Willamette Meridian, just northeast of the
town of Shelton, Washington.
We understand that Manke Family Resources intends to extend the mine to its eastern grading limits.
HU1 represents the treed area between the existing mine pit and the permitted eastern grading limits.
We understand that Manke Family Resources intends to clear cut HU1 and then regrade the area to a
2HAV (Horizontal:Vertical) slope to the west into the open pit mine in accordance with the Final
Reclamation Map, prepared by Sitts & Hill Engineers, Inc. (Sits & Hill), dated December 16, 2015. We
understand that the mining operation is already permitted to the grading limits and that this evaluation
is limited to the proposed timber harvest that will precede the mining operation.
The eastern grading limits extend to a 10-foot setback from the boundary of the adjoining East State Route
3 (SR-3) right-of-way or a 200-foot setback from the shoreline of Oakland Bay, whichever is greater. HU1
is situated on a southeast facing slope above SR-3. Its western boundary is at the top of the slope at an
elevation of approximately 190 feet above sea level (asl)with the mine cut slope immediately to the west.
HU1's eastern boundary is situated about half-way down the southeast facing slope terminating at
elevations of approximately 60 to 150 feet asi.
GEOLOGIC CONDITIONS
Surficial geologic conditions for the project vicinity are depicted on the Geologic Map of the Shelton 7.5-
minute quadrangle, Mason and Thurston Counties, Washington, prepared by Schasse, H.W., et al., dated
2003 (Schasse et al., 2003). According to this map, HU1 is underlain by the Vashon Recessional Outwash
unit (map unit Qgo).The Vashon Recessional Outwash unit is mapped overlying the Vashon Till unit (map
unit Qgt), which in turn overlies the Pre-Vashon Gravel unit (map unit Qpgo). A portion of this map is
reproduced as Figure 3, Geologic Map.
ZGA was provided with a copy of the geology section excerpted from the FEIS for the Johns Prairie Site
prepared for the Mason County Department of Community Development, dated May 1995 (FEIS, 1995)
and a copy of the Geotechnical Critical-Area Evaluation, Johns Prairie Mine Expansion, prepared by
Associated Earth Sciences, Inc., dated June 2, 2016 (AESI, 2016). Both reports describe a geologic setting
that is generally consistent with the mapping by Schasse et al. The FEIS interprets that the Johns Prairie
site is underlain by Vashon Recessional Outwash Sand and Gravel (map unit Qvr), which overlies Vashon
Glacial Till (map unit Qvt), which in turn overlies an "older, complex sequence of sediments". This basal
unit likely corresponds to the Pre-Vashon Gravel unit(map unit Qpgo) described by Schasse et al.
The AESI report incorporates subsurface data collected by McLucas and Associates, Inc. (McLucas) from
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ZGA Project No. 2787.07.1
Veoprotesswnal Consultants
March 28, 2024
their Investigation of the Quality and Quantity of Sand and Gravel Contained Within the Johns Prairie Site,
dated November 27, 1997. Reportedly, McLucas advanced 13 borings (DH-1 through DH-13) in the mine
area,two of which were completed as groundwater monitoring wells(DH-2 and DH-13). Of these borings,
DH-2, DH-11, and DH-13 are located nearest to the HU1 project area and were advanced from elevation
approximately 190 to 200 feet asl to depths of approximately 155, 185,and 110 feet below ground surface
(bgs), respectively.The geologic conditions described on boring logs for DH-2, DH-11,and DH-13 generally
consist of sandy gravel or gravelly sand with minor quantities of silt typically as coatings on gravels over
silty or clayey sediments at depths of greater than 180 feet bgs in boring DH-11 and 100 feet bgs in boring
DH-13.
Based on our observations of cut slopes within the Johns Prairie Mine and above SR-3 as well as our review
of published geologic maps and previous investigations by others, we interpret that the geology of the
HU1 project area is generally composed of coarse-grained glacial outwash sediments over fine-grained
glacial till.These units are generally described below in stratigraphic order(youngest to oldest).
Vashon Recessional Outwash (Qgo/Qvr)
The term Vashon Recessional Outwash generally applies to sediments deposited by streams and rivers
that emanated from the retreating continental ice sheet of the Vashon Stade of the Fraser Glaciation.The
high energy of these streams caused erosion of pre-existing surficial deposits, which were sorted by the
running water and eventually deposited downstream as outwash. As a result, the deposits left by these
recessional outwash streams typically appear as normally consolidated, coarse grained, poorly graded,
free draining, sand, and gravel, although fine grained layers or lenses may be incorporated.
The FEIS reports that the "eastern portion of Johns Prairie(including the mine site)is dominated by a thick
layer of this glacial deltaic outwash gravel." The FEIS further states "Driller's logs indicate that the deposit
is more than 185 feet thick beneath the more easterly portion of the subject site."These deposits are the
focus of the Johns Prairie surface mining efforts for use as construction aggregate. Proposed HU1 is
located in the eastern portion of the Johns Prairie site where the Vashon Recessional Outwash unit is
thickest.
Based on our field observations and a review of readily available geologic information, we interpret that
the slope on which HU1 is located, above SR-3, is composed of sediments belonging to the Vashon
Recessional Outwash unit.
Vashon Till (Qgt/Qvt)
The term Vashon Till generally applies to sediments deposited by the continental ice sheet of the Vashon
Stade of the Fraser Glaciation.Vashon Till in the project vicinity is described as "a heterogeneous mixture
of clay, sand, gravel, and cobbles" "deposited as a compact, unstratified mixture of sediments in a matrix
of clay, referred to as glacial till. Glacial till often resembles low-grade concrete and is commonly referred
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Forest Practice Engineering Geology Evaluation Proposed Johns Prairie Harvest Unit 1 ZipperGeo
ZGA Project No.2787.07.1
Geoprofessional Consultants
March 28, 2024
to as 'hardpan'." (FEIS, 1995). The high fines content of the sediment matrix and the over-consolidated,
unstratified, nature of glacial till results in a geologic unit that is effectively impermeable to groundwater
infiltration.
The FEIS reports that Vashon Till was encountered at ground surface at the northwestern boundary of the
Johns Prairie site and was approximately 13 feet thick in that location. From there,the till surface appears
to dip to the east where it is overlain by the Vashon Recessional Outwash. We expect that the Vashon Till
unit is continuous below the Vashon Recessional Outwash unit across the Johns Prairie site including
below HU1 and that the local groundwater table likely occurs above the geologic contact. East-West Site
Section 03, presented by Sits &Hill, and reproduced on Figure 5,Mine Reclamation Map, depicts the local
seasonal high groundwater table below the HU1 project site,and by extension the geologic contact, at an
elevation of approximately 25 feet asl or below,which is equivalent to 165 feet or greater bgs as measured
from the top of the slope.This is generally consistent with the subsurface conditions described by McLucas
in their boring logs.
HYDROGEOLOGIC CONDITIONS
A hydrogeologic study was conducted of the Johns Prairie site by Robinson & Noble, Inc. (RNI). We were
provided with figures from RNI's "Monitor Plan" dated August 17, 2001. According to RNI Figure 1, Well
and Cross-Section Location Map, thirteen "Drill Holes" (DH-1 through DH-13)were advanced on the Johns
Prairie site.Two of these explorations(DH-2 and DH-13)were completed as groundwater monitoring wells
(piezometers). In addition, groundwater elevations were monitored from piezometers installed in the
north central portion of the site (Gravel Pit Piezometer), another in the east central portion of the site
(Armstrong Well), and a third in the southeast portion of the site (Observation Well). Groundwater
elevation contours are presented on RNI Figure 1, Johns Prairie Reclamation Topography Map. The
prevailing direction of groundwater flow is to the southeast at an elevation of 25 feet asl or lower in the
vicinity of HU1, which is equivalent to 165 feet or greater below ground surface (bgs) as measured from
the top of the slop.
East-West Site Section 03, prepared by Sits & Hill depicts the seasonal high groundwater table as dipping
to the east towards Oakland Bay at a gradient that is generally consistent with RNI's groundwater
elevation contour map. Below HU1,the water table is similarly depicted at an elevation of approximately
25 feet asl or below.
We expect the Vashon Recessional Outwash unit to act as an aquifer and for the underlying Vashon Till
unit to act as an aquitard. We interpret that the water table depicted by RNI and Sits& Hill represents an
unconfined aquifer perched within the Vashon Recessional Outwash unit above the Vashon Till contact.
Groundwater was not observed within the mine during our site reconnaissance nor were groundwater
seeps observed in the hillside above SR-3 or in the mine cut slope near HU1. Based on these observations,
and the subsurface profile depicted by Sits & Hill, we interpret that the local water table dips to the east
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ZGA Project No.2787.07.1
Geoprofessional Consultants
March 28,2024
and discharges to Oakland Bay at roughly sea level and does not intersect with the slope above SR-3 in
the vicinity of the proposed harvest.
MAPPED LANDSLIDE HAZARDS
We accessed the Washington Geologic Information Portal (WGIP) and reviewed the landslide hazard
database curated by the Washington State Department of Natural Resources(WA-DNR).According to this
database, three suspect deep-seated landslide polygons are mapped within the general vicinity of HU1,
although none overlap with the harvest unit itself. The approximate locations of the suspect landslide
polygons are depicted on Figure 2, Hillshade Map.These features include two small landslide polygons to
the northeast of HU1 within the cut slope above SR-3 classified as "Activated, Reactivated, Recent" per
the WGIP (features LS1 and LS2 on Figure 2), and one larger landslide polygon to the southwest of HU1
that encompasses the entire south-facing slope leading down to Oakland Bay classified as "Dormant
Relict" per the WGIP (feature LS3 on Figure 2).
We also reviewed the Mason County Coastal Zone Atlas Slope Stability Map. According to this map, the
southeast facing slopes above SR-3 are classified as "Intermediate" in terms of slope stability, and the
slopes below SR-3 are classified as"Unstable".The level portions of HU1 above the southeast facing slope
including the majority of the Johns Prairie site are classified as "Stable".
The FEIS interprets that the slopes in the HU1 project area are composed of well-drained glacial outwash
sand and gravel of moderate density. It is the author's interpretation that these slopes are inherently
stable when allowed to stand at their natural angle of repose, which they estimate is approximately 30
degrees from horizontal (57.7%slope), and do not possess geologic characteristics that would otherwise
create conditions of slope instability. Based on this conceptual slope stability model, the conditions that
would be likely to create an unstable slope would be oversteepening beyond the angle of repose or
removal of the toe of support at the base of the slope. Erosion potential also increases under such
conditions.
AESI SLOPE STABILITY ANALYSIS
AESI conducted a global slope stability analysis of the slope located just north of the HU1 project area.
This analysis was conducted with the Slope/W software and evaluated the mine cut slope and the"natural
steep slope" above SR-3 under pre-mining and post-mining conditions, each under static and seismic
conditions. Based on their analysis, the factor of safety for the slope above SR-3 in the pre-mining
condition was calculated as 1.29 and 0.96 under static and seismic conditions, respectively. The factor of
safety for the same slope in the post-mining condition was calculated as 1.29 and 0.97 under static and
seismic conditions, respectively. In both models,the slope above SR-3 is unstable under seismic conditions
(FOS<1).AESI concluded that"Although the calculated minimum factors of safety fall below the minimum
values of 1.5 and 1.1 specified in the[Mason County Code], the results also indicate that the mining will
not negatively impact the stability of the natural steep slope."
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Forest Practice Engineering Geology Evaluation Proposed Johns Prairie Harvest Unit 1 ZipperGeo
ZGA Project No. 2787.07.1
March 28,2024 Geoprofessional Consultants
LiDAR REVIEW
We reviewed the 2019-dated, Olympics South OPSW digital elevation model (DEM).A portion of this data
is presented as Figure 2, Hillshode Map. We also reviewed the 2005-dated, Puget Lowlands DEM. These
data were reviewed for indications of slope instability and previous landslide activity such as:
• concave and convex slope features;
• step-like morphology;
• semi-circular morphology;
• hummocky and irregular topography;
• back-tilting of slope faces;
• in-filled valleys;
• landslide scars;
• de-vegetated areas;
• interrupted and anomalous drainage patterns; and
• other indications of deep-seated landslide activity as described in Part 6 of Section 16 of the Forest
Practices Board Manual (2016) and by Turner and Schuster(1996, Table 8-5).
In the 2005-dated LiDAR imagery,the proposed HU1 project area is located on a planar, southeast facing
slope.A kettle feature is apparent to the west of HU1 and the mine's footprint is limited to the southwest
portion of the Johns Prairie site.The slope above SR-3 steepens near the base of the slope above the road.
Figure 4, Previous Ground Surface, 2006 or Earlier, presents a topographic survey of the Johns Prairie site
that is generally concurrent with the 2005-dated LiDAR imagery.
In the 2019-dated LiDAR imagery,the slope above SR-3 in the vicinity of HU1 appears largely unchanged.
The mine operation now abuts the western boundary of HU1. The cut slope down into the mine appears
planar and consistent. The kettle depression has been removed by the mining operation.
We reviewed the morphology of the suspect landslide features depicted on the WGIP. No obvious signs
of previous landslide activity were apparent in the vicinity of LS1 and LS2, located in the cut slope above
SR-3. LS3 exhibits a concave morphology above irregular, hummocky terrain. These terrain features
appear mature with an overall rounded, muted appearance, consistent with a dormant, relict landslide
feature.
We observed a steeply sloping, convergent feature above a nearly level area to the southwest of HU1. A
bench is apparent at the top of the feature. We interpret that this feature is a man-made cut slope
associated with a residence adjoining SR-3 and is not indicative of previous landslide activity.
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Forest Practice Engineering Geology Evaluation Proposed Johns Prairie Harvest Unit 1 ZipperGeo
ZGA Project No. 2787.07.1
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AERIAL PHOTO REVIEW
We reviewed historical aerial photographs for signs of slope instability and previous landslide activity near
the project area. Aerial photos were acquired from Environmental Data Resources (EDR) dated 1951 to
2019, at irregular intervals. In 1951 dated aerial imagery, the HU1 project area is fully forested, SR-3 is
apparent to the east, some bare soil is visible in the cut slope just above SR-3, and beach deposits are
apparent along the shore of Oakland Bay. These features appear largely unchanged throughout the
historical aerial photograph report and the HU1 project area remains fully forested. In 1968 dated aerial
imagery, a rectangular patch of bare earth appears to the southwest of HU1. This area of bare earth
appears to correspond to the location of the residential cut slope described in our LiDAR review section
and called out on Figure 2, Hillshade Map. No significant changes are noted until 1990 when access roads
appear in the Johns Prairie mine area to the northwest. By 2006 the surface mining operation is visible,
and the operation expands to the northeast through the remainder of the photographs. By 2015 the
surface mining operation abuts the western boundary of HU1. In the 2019 aerial photograph a clear cut
adjoins HU1 to the northeast. No obvious signs of slope instability or landslide activity were observed in
the vicinity of HU1 in our review of historical aerial photographs.
OBSERVED SITE CONDITIONS
ZGA performed a site reconnaissance of the HU1 project area on January 26, 2024. We were joined by
representatives of Manke Family Resources. A GPS track of our site reconnaissance is depicted on Figure
2, Hillshade Map.We accessed the Johns Prairie mine site by vehicle from "The Other Road"off SR-3, met
with the mine's Foreman,and proceeded up to HU1 from a mining access road along the top of the slope.
We walked along the ridgeline and observed the conditions of the cut slope into the mine and of the clear
cut that adjoins HU1 to the north.The cut slopes into the mine exhibited a slope of approximately 60%to
65% and appeared generally stable with a small talus slope at the base. No groundwater seeps were
observed in the cut slope. The clear cut to the north has been regraded to slope down to the west into
the mine at a slope of less than 20%. No signs of undue erosion or slope instability were observed in the
clear cut area or in the adjoining slope to the east. Harvest and regrading in this vicinity does not appear
to have resulted in delivery sediment to SR-3 below. The adjoining clear cut provides some insight into
the likely performance of the HU1 project area.
After walking the ridgeline, we traversed downslope to the east and then to the southwest along the
eastern boundary of HU1. Slopes within HU1 were measured as 26%to 53%. Cut slopes above SR-3 to the
east of HU1 increased to approximately 60% to 75%. The harvest unit is forested by mature, vertically
oriented fir trees, pine trees, madrones, cedar, and vinemaple. The understory generally consists of
blackberries and scotch broom at the margins with evergreen huckleberry, sword ferns, nettles, and salal
below the canopy. HU1 is fully vegetated, but bare soil is exposed in the cut slope above SR-3 with few
young trees established. A slight downhill lean was noted in a few trees at the top of the cut slope,
suggesting that shallow mass wasting processes, such as erosion and soil creep, may be occurring at the
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ZGA Project No. 2787.07.1
veoprofesswnal Consultants
March 28,2024
transition.
We performed shallow explorations with hand tools in the HU1 project area to depths of approximately
1 foot. Soil conditions within these explorations appeared to consist of roughly 6 inches of topsoil over
loose, moist, light brown, gravelly sand to sandy gravel. These soil conditions appear consistent with the
soils exposed in the mine to the west and in the cut slope to the east. No groundwater seeps or surface
water features were observed in the project area.
CONCLUSIONS AND RECOMMENDATIONS
We have completed a reconnaissance level engineering geology assessment of the proposed Harvest Unit
1 (HU1) at the Manke Family Resources' Johns Prairie open pit mine site located near Shelton,
Washington. We understand that the proposed forest practice consists of a clear cut of the trees within
HU1 and that after harvest, the Johns Prairie open pit mine will be expanded to its eastern grading limit,
established at the eastern boundary of HU1. We understand that the slope within the HU1 project area
will then be regraded to a 2H:1V slope (Horizontal:Vertical) down to the west into the mine in general
accordance with the East-West Site Section 03 of Figure 2.2 of the Reclamation and Operation Plan,
prepared by Sits & Hill, dated 2016. A portion of this plan is reproduced as Figure 5, Mine Reclamation
Map. Our conclusions and recommendations are presented below.
WGIP Mapped Landslide Features
There are three mapped suspect landslide features in the project vicinity according to the WGIP's landslide
hazard inventory.These features (LS-1, LS-2, and LS-3) are delineated on Figure 2, Hillshade Map.
LS-1 and LS-2 are classified by the WGIP as "Activated, Reactivated, Recent". These features are located
within a steep cut slope that appears to be subject to erosion and soil creep, but landslide morphology
was not observed during our assessment. These suspect features are located outside of the proposed
harvest area and it is our opinion that the risk that the proposed forest practice will cause or contribute
to movement in their vicinity is low.
LS-3 is classified by the WGIP as "Dormant, Relict". In our opinion, the morphology of LS-3 appears
consistent with a dormant, relict landslide,which likely occurred during the retreat of the last continental
glaciation of the Puget Lowland. Evidence of more recent movement was not observed during our
assessment. This feature is located outside of the proposed harvest area and its groundwater recharge
area is already heavily modified by the mining operation. It is our opinion that the risk that the proposed
forest practice will cause or contribute to movement in the vicinity of LS-3 is low.
Other Potentially Unstable Landforms
Slope stability analyses conducted by AESI of the slope above SR-3 indicate that the slope is unstable under
a seismic condition. During our site reconnaissance, indications of shallow soil mass wasting processes,
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Forest Practice Engineering Geology Evaluation ZipperGeo
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ZGA Project No. 2787.07.1 Geoprofessional Consultants
March 28, 2024
such as erosion and soil creep, were observed in the steepest portion of the slope located to the east of
the HU1 project area in the cut slope adjoining SR-3. Therefore, the cut slope above SR-3 qualifies as a
Rule Identified Landform (RIL). However, the proposed forest practice does not overlap with this area of
apparent shallow instability. Provided that appropriate TESC measures are implemented during harvest,
it is our opinion that the risk that the proposed forest practice will cause movement or contribute to
further movement of this slope is low.
We interpret that the conditions that would be likely to create an unstable slope in the project area would
be oversteepening of cut slopes beyond the angle of repose or removal of the toe of support at the base
of a slope. The FEIS estimates the angle of repose for site soils as 30 degrees or 57.7% slope. AESI
measured cut slope angles within the mine as 30 to 33 degrees or 57.7% to 64.9% slope. Our
measurements were generally consistent with AESI.The proposed regrade to a 2H:1V(Horizontal:Vertical)
is equivalent to approximately 27 degrees or 50% slope, which is below the estimated angle of repose.
Slope stability analyses performed by AESI suggest "that the mining will not negatively impact the stability
of the natural steep slope."(AESI, 2016)
Based on our assessment, as required by WAC 222-10-030, we offer the following:
1. The likelihood that the proposed forest practices will cause movement on the potentially unstable
slopes or londforms, or contribute to further movement of a potentially unstable slope or
landform.
It is our opinion that there is a low likelihood that the proposed forest practices will contribute to
further movement of a potentially unstable slope or landform provided that appropriate, site-
specific TESC measures are implemented during harvest and that the slope is regraded after
harvest per the Reclamation and Operation Plan.
2. The likelihood of delivery of sediment or debris to any public resources, or in a manner that would
threaten public safety.
It is our opinion that there is a low likelihood of delivery of sediment or debris to public resources
or in a manner that would threaten public safety provided that appropriate, site-specific TESC
measures are implemented during harvest and that the slope is regraded after harvest per the
Reclamation and Operation Plan.
3. Any possible mitigation for the identified hazards and risks.
We recommend that site-specific TESC measures be implemented during harvest to mitigate
sediment delivery to SR-3 and that the slope is regraded after harvest per the Reclamation and
Operation Plan.
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Proposed Johns Prairie Harvest Unit 1 Zi P pe r G e o
ZGA Project No. 2787.07.1
March 28,2024 Geoprofessional Consultants
LIMITATIONS
This report has been prepared from a reconnaissance-level assessment of the site. We have addressed
overall site conditions. Although we believe that our reconnaissance has provided us with a good
understanding of the overall site conditions, the entire site has not been observed and specific locations
within the site may have characteristics different than those described in this report. If conditions appear
different than those described in this report, or if other concerns arise, we request that we be notified so
we can review those areas and modify our recommendations as required.
There are inherent risks associated with forest practice activities on or adjacent to steep slopes that the
owner must assume. This report is intended to reduce, but not eliminate, uncertainty regarding the
stability of slopes and the potential for sediment delivery under harvested conditions. Forest practice
activities on or near a slope will always involve risk,especially under severe weather or seismic conditions.
CLOSURE
We appreciate the opportunity to provide our services. If you have questions regarding this report or if
we can be of further assistance, please contact the undersigned.
Respectfully Submitted,
Zipper Geo Associates, LLC 1 /
o`W a shf
Eng:neelmg GeO1096t
o3 d Geo�o 3/28/2024 —
JEFFREY S.TINKLEPAUGH
Jeffrey S.Tinklepaugh, LG, LEG Martin R. Cross, LG
Senior Geologist Project Geologist
James P. Georgis, LG, LEG
Principal Engineering Geologist
Distribution: Addressees, One Copy, Electronic
Enclosures: Figures 1—5
EDR Historical Aerial Photograph Report
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Forest Practice Engineering Geology Evaluation Proposed Johns Prairie Harvest Unit 1 ZipperGeo
ZGA Project No. 2787.07.1
Geoprofessional Consultants
March 28, 2024
REFERENCES
Associated Earth Sciences, Inc., Geotechnical Critical-Area Evaluation,Johns Prairie Mine Expansion,June
2, 2016.
Environmental Data Resources, Inc., The EDR Aerial Photo Decade Package, Manke Family Resources,
Johns Prairie, February 21, 2024.
Mason County Department of Community Development, Final Environmental Impact Statement,Johns
Prairie Site, Sand and Gravel Excavation and Barge-Loading Facility, (partial report), dated May
1995.
Puget Sound Lidar Consortium, Olympic Peninsula, Washington 3DEP LiDAR—Area 1 Technical Data
Report, July 2019.
Robinson & Noble, Inc., Monitor Plan, (partial report), dated August 17, 2001.
Schasse, H.W.,et al., Geologic Map of the Shelton 7.5-minute quadrangle, Mason and Thurston Counties,
Washington, 2003.
Sits & Hill Engineers, Inc., Reclamation and Operation Plan, 2016
Turner, A.K., and Schuster, R.L., Landslides, Investigations and Mitigation:Special Report247,
Transportation Research Board, National Research Council, 1996.
Washington State Department of Natural Resources, 2016, Forest Practices Board Manual.
Page 1 11
LEGEND
N -
EAST JOHNS PRAIRIE RD r —1 PROPOSED HARVEST UNIT 1
I J (HU1)
BAYSHORE
t
"ram
0
PROPOSED HARVEST UNIT 1
�O
�P
Pg a
JOHNS PRAIRIE MINE
OAKLAND BAY
SHELTON
MANKE LUMBER JOHNS PRAIRIE HARVEST UNIT t
3500 E Johns Prairie RD
.. .. ...-; .. .:. ,.., .. .: .' .: Shelton,Washington
PROJECT LOCATION MAP
REFERENCE:GOGGLE EARTH AERIAL IMAGERY,DATED JULY 6 2022
NOT TO SCALE DATE:MARCH 2O24 Job No. 2787.07.1
Zipper Geo Associates,LLC FIGURE
19019 36th Ave.W.,Suite E
Lynnwood,WA SHT.1of1
LEGEND
PROPOSED HARVEST UNIT 1
L--J (HU1)
SURFACE MINE EASTERN CUT TAX PARCEL BOUNDARY
SLOPE AS OF 2019
LS2
(ARR) ® SUSPECT LANDSLIDE FEATURES
IDENTIFIED BY WASHINGTON
STATE GEOLOGIC INFORMATION
PORTAL
+ J ZGA SITE RECON GPS TRACK
PROPOSED HARVEST UNIT 1 is _ 1�Y
� ACRONYMS _
ACTIVATED,REACTIVATED,
, ARR RECENT
(DNR DSLS MORPHOLOGY)
DR DORMANT RELICT
APPROXIMATE CUT SLOPE (DNR DSLS MORPHOLOGY)
. ABOVE SR 3
LS1 SUSPECT LANDSLIDE
FEATURE ID
DEPARTMENT OF NATURAL
DNR RESOURCES
�r
�E 1•
DSLS DEEP SEATED LANDSLIDE
,I, fTJ
I
N
APPARENT RESIDENTIAL CUT SLOPE
LS3
(DR)
300 0 150 300
SCALE IN FEET
MANKE LUMBER JOHNS PRAIRIE HARVEST UNIT 1
3506 E Johns Prairie RD
Shelton,Washington
HILLSHADE MAP
REFERENCE:Olympic Peninsula,Washington 3DEP LiDAR-Area 1 Technical Data Report(July 2019).Quantum Spatial,OR.,Puget Sound UDAR Consortium,Seattle,WA.https://pugetsoundtidar.ess.washington.edu/
Washington State Department of Natural Resources,Washington Geologic Information Portal,Other Compiled Landslide Mapping Layer,accessed 1/25/2024. DATE:MARCH M4 Job No. m7.07.1
ALL LOCATIONS ARE APPROXIMATE Zlpp 1-11soclarss,LLC FIGURE ^
19019 361h Ave.W.,Suite E
Lynnwood,WA I SHT.1 of 1
i LE
- - - - ' _
j� GEND
I _
Q g Or -1PROPOSED HARVEST UNIT 1
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SCALE IN FEET
r
MANKE LUMBER JOHNS PRAIRIE HARVEST UNIT 1
3500 E Johns Prairie RD
Shelton,Washington
GEOLOGIC MAP
REFERENCE:Geologic Map of the Shelton 7.5-minute Ouadrangel,Mason and Thurston Counties,Washington,Washington State Department of Natural Resources.Open File Report 2003-24,(2003)
ALL LOCATIONS ARE APPROXIMATE DATE:MARCH M4 Job No. 2787.07.1
Zipper Geo Associate',LLC FIGURE
19019 36th Ave.W..Suite E 3
Lynnwood,WA SHT.1 o11
LEGEND
STING RETENTION PON ` --.-4�—— —— 'J �/ PROPOSED HARVEST UNIT i
UN
N74"24'T'W _ ( // / � _ SO
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...�—OAKLANO PIONEER MEMORIAL AND
GROUND WAFER MONITORING WELL
MANKE LUMBER JOHNS PRAIRIE HARVEST UNIT 1
3500 E Johns Prairie RD
Shelton,Washington
PREVIOUS GROUND SURFACE PRIOR
REFERENCE:Johns Prairie Mine Expansion,Existing Topographic Map,Figure 1.0,Sifts&Hill Engineers,Inc.(December 16,2015) 2006 OR PRIOR
EXACT DATE OF TOPOGRAPHIC MAP NOT PROVIDED ON SURVEY,DATE ESTIMATED BASED ON AERIAL PHOTOGRAPHS DATE:MARCH 2O24 Job No. 2W 07.1
ALL LOCATIONS ARE APPROXIMATE Zipper Geo ASso i-tes,LLC FIGURE A
19019 36th Ave.W.,Suiie E
Lynnwood,WA SHT.1o11
f
LEGEND
Y\ .yf/�\�' a\ /y,� L ��•,` I I PROPOSED HARVEST UNIT 1
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LOCATION of /
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i PROPOSED HARVEST UNIT 1
�.,50_,_,�,,.
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SCALE IN FEET
450 450
400 Z i-..._.R---.l _. a .400
350
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MINE GRADING LIMIT I J REFERENCE'
MINING GRADING LIMIT Johns Prairie Mine Ex
250 rc ansion,Final
250 EXISTING .'"""�f" ...PRONDE 16 WIDE TOP all ..___ p
/ ` f cRouNO OF(BERM TYP. a l Reclamation Map Figure 2.1,Sills&Hill
200 --��� ��� \— *... �._...�.� _._ 200 Engineers,Inc.(December 16,2015)
10 MIN',TOP OF BERM
FROM PROPERTY UNE Johns Pfalfl Mine ion,Site
-- ---- ---- \! a Expansion, it
15O - -e MNtD; -^ - tso Sections,Figure 2.2,Sifts&Hill
�\\ \�h l� Engineers,Inc.(December 16,2015)
...
0o EXISTING SEASONAL HIGH \ /// \ oo ALL LOCATIONS ARE APPROXIMATE
WATER GROUNDWATER TABLE
50
0 ,..., ...... I -�= 0 MANKE LUMBER JOHNS PRAIRIE HARVEST UNIT 1
i 3500 E Johns Prairie RD
Shelton,Washington
-50 -50
0+00 3+00 6+D0 9+00 12+00 15+00 18+00 21+00 24+00 27+00 30+00 33+OD 36+00 MINE RECLAMATION MAP
EAST- WEST SITE SECTION(LOOKING NORTH) DATE:MARCH 2O24 Job No. 2787.07.1
uV HORIZONTAL SCALE:1"=300', VERTICAL SCALE: 1'=100' Zipper Geo Associate s,LLC FIGURE
19019 36th Ave.W.,Suite E 5
Lynnwood,WA SHT.1 of 1
Manke Family Resources, Johns Prairie
3500 E Johns Prairie Road
Shelton, WA 98584
Inquiry Number: 7573519.1
February 21, 2024
The EDR Aerial Photo Decade Package
6 Armstrong Road,4th floor
Shelton, CT 06484
Toll Free: 800.352.0050
(rE DR www.edrnet.com
EDR Aerial Photo Decade Package 02/21/24
Site Name: Client Name:
Manke Family Resources, Johr Zipper Geo Associates, LLC 3500 E Johns Prairie Road 19019 36th Ave W SUITE E CEDR
Shelton, WA 98584 LYNNWOOD, WA 98036
EDR Inquiry# 7573519.1 Contact: Jeffrey Tinklepaugh
Environmental Data Resources, Inc. (EDR)Aerial Photo Decade Package is a screening tool designed to assist
environmental professionals in evaluating potential liability on a target property resulting from past activities. EDR's
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Search Results:
Year Scale Details Source
2019 1"=1000' Flight Date: October 10, 2019 USGS
2015 1"=1000' Flight Date: July 28, 2015 USGS
2011 1"=1000' Flight Date: August 01, 2011 USGS
2006 1"=1000' Flight Date: July 24, 2006 USGS
1990 1"=1000' Flight Date: July 10, 1990 USGS
1980 1"=1000' Flight Date: July 29, 1980 USGS
1973 1"=1000' Flight Date: May 28, 1973 USGS
1968 1"=1000' Flight Date: September 04, 1968 USGS
1957 1"=1000' Flight Date: July 18, 1957 USGS
1951 1"=1000' Flight Date: August 16, 1951 USGS
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7573519 - 1 page 2
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