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GeoTest Services, Inc.
<br /> May 3, 2019
<br /> Mukilteo School District
<br /> 19-0194
<br /> ',$,, The fill then became medium dense, brown, damp
<br /> e - to moist, very gravelly, silty sand and contained
<br /> ' " �° '" scattered organics. This unit extended to the base
<br /> , . ri,, of TP-1, which occurred at 8.5' BGS due to
<br /> ' c Y' "-- ` _ ' ..4,; .�i.R equipment depth limitations. Within TP-2, contact
<br /> �,r,. u•;} ,,, •k� 7 •-•••:-.,-.4 with very dense, gray, damp to dry, silty, sandy
<br /> ▪ . rT''`,•g ,, _ , --Y--":".:;":":,.- -,: w'w
<br /> �6 a :� r , -..-;,‘„.2.--0=:,-:.. ti . gravel, interpreted as native Glacial Till occurred at
<br /> y f v�pr:" '. ..,0,1-,---, '' a. approximately 6.0 feet below ground surface(BGS).
<br /> • s ,� �4 � .,K �, `'� r„. -A; ', In this location,Glacial Till material was observed to
<br /> ,. ” ,-714:-.N the terminal depth of this exploration, which
<br /> „.‘,5,7t,,,,*: ,--.--,4,1p—::'" h°.* '3 ','� k occurred at 8.5 feet BGS.
<br /> R
<br /> tts
<br /> .r „ � -4YfA -441.1`"`- ; - ,rip.*�:. Within the eastern most test pit explorations, TP-3
<br /> b Is
<br /> _ and TP-4, medium dense to dense, variegated tan,
<br /> « ;1.7,:,knig,C:i" "19`- i,:",)-- gray, brown and lightly mottled, damp, silty,
<br /> /. ar0 �-. f;z ° �'Q'".' f, -` „z, i f.; gravelly sand, interpreted as Previously Placed Fill
<br /> ' �, .• , ,`'P` �w • • ., � , , extended to approximately 2.0 feet BGS from the
<br /> ;� : 'w•„.,,, rii�", �"�`i �A�1,r-44,47':<1'4 surface.The fill then became medium dense, brown
<br /> 'ir,�?�' ' '� • r��`' to dark brown,silty to very silty sand that contained
<br /> is r. _, ."z.=., , V .,. .a:. `, scattered to numerous organics was observed
<br /> 3• .. �; (Image 2). At approximately 6.0 and 8.5 feet BGS
<br /> 1OW ` §s�' ':I " within TP-3 and TP-4, respectively, the fill became
<br /> Image 2(above)—Excavated material from approximately medium dense, dark tan to light brown, damp to
<br /> 6.0 feet BGS within TP-4—Note considerable organic content. moist, gravelly, silty sand, and extended to the
<br /> terminal depth of the subject test pits.
<br /> General Geologic Conditions
<br /> According to the Geologic Map of the Everett 7.5-Minute Quadrangle, Snohomish County, Washington,
<br /> general geologic conditions at the site consist of Pleistocene aged glacial till (Vashon Till) deposits from
<br /> the Vashon Stade of the Fraser Glaciation. Vashon Till was deposited directly by ice as it advanced over
<br /> bedrock and older quaternary sediments. These deposits typically mantle hills, ridges and slopes and are
<br /> composed of a very dense, nonsorted mixture of mud, sand, pebbles, cobbles and boulders (Minard,
<br /> 1985). This unit is commonly referred to as hardpan and its density is partly due to the weight of
<br /> overriding ice, known to have been several hundreds of meters thick. Our on-site explorations indicate
<br /> that the encountered subsurface soil conditions are in accordance with the mapped soil unit.
<br /> Groundwater
<br /> Groundwater was not encountered at the time of our subsurface explorations. The groundwater
<br /> conditions reported on the exploration logs are for the specific locations and dates indicated, and
<br /> therefore may not be indicative of other locations and/or times. Groundwater levels are variable and
<br /> groundwater conditions will fluctuate depending on local subsurface conditions, precipitation, and
<br /> changes in on-site and off site use.
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