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Mr. Mark Johnson
<br /> January 24,2020
<br /> Page 2
<br /> generally consisting of clayey and silty sands;2)sand and gravel alluvial deposits that underlie the overburden and
<br /> overlie the bedrock;and 3)bedrock usually consisting of sandy claystone with local areas of sandstone. These units are
<br /> described in more detail below.
<br /> 3.5.1 Overburden Unit
<br /> The overburden at the site typically consists of brown clayey to silty sand that locally overlies a buff silty sand. The
<br /> surficial brown clayey to silty sand overburden unit is typically approximately 2 to 3 feet thick with the top 6 to 8 inches
<br /> containing significant organics. This unit locally is thinner to not present or is locally as thick as 5 feet.
<br /> 3.5.2 Sand&Gravel Unit
<br /> The sand and gravel is present throughout the site underlying the overburden and overlying the bedrock. This unit
<br /> typically consists of gravelly,fine to coarse grained sand locally grading to sandy gravel. This unit ranges in thickness
<br /> from approximately 10 feet to 22 feet.
<br /> 3.5.3 Bedrock
<br /> The bedrock encountered in the exploratory borings was generally weathered in the upper one to two feet typically
<br /> became harder in unweathered zones. The bedrock consisted of sandy claystone with local sandstone. The
<br /> approximate top of bedrock contours are presented on Figure 1.
<br /> 3.5.4 Groundwater
<br /> Groundwater was encountered in all of the borings at approximately 4 to 9 feet below ground surface.The groundwater
<br /> levels will vary seasonally and will typically rise during the irrigation season. Groundwater will be controlled with the
<br /> proposed below grade slurry wall. After slurry wall construction,groundwater mounding is anticipated on the upgradient
<br /> (west and south)side of the site and a groundwater shadow(deeper water table)is anticipated on the downgradient
<br /> (north and east)side the site.
<br /> From a geotechnical standpoint,the sand and gravel will form the majority of the mine slopes. These soils are generally
<br /> strong and stable, particularly when dewatered. Submittal
<br /> STRUCTURES WITH 200 FEET OF DISTURBED AREAS
<br /> The known,permanent, man-made structures within 200 feet of the proposed mine areas that are not owned by Burnco
<br /> are listed below:
<br /> UTILITIES:
<br /> CENTRAL WELD WATER,ST. VRAIN SANITATION,KERR-MCGEE OIL&GAS/ANADARKO/OXY, NOBLE ENERGY,
<br /> UNITED POWER,CENTURY LINK,WELD COUNTY PUBLIC WORKS, RURAL DITCH,LAST CHANCE DITCH,TOWN
<br /> OF FIRESTONE.
<br /> HOME OWNERS WITH HOUSES WITHIN 200':
<br /> NEUMANN JAMES A,AILOR MICHAEL JOSEPH, NORTON GARY L,WEBER ROBERT ALAN,GROUND WATER
<br /> MANAGEMENT SUBDISTRICTOF THE CCWCD, VARRA CHRISTOPHER, MILLER ROBERT L, L00 MOISES,
<br /> SALAZAR MATTHEW J,RALSTON LAWRENCE ALLAN,MEISNER DAWN J,CLARK ROBERT, FREAS PETER W,
<br /> STYPA ERIC, NIETO CHIRELLE,JOHNSON RICHARD K, RADEMACHER VINCE, NEWCOMB RICHARD SCOTT JR,
<br /> AVESTRUZ ANTHONY C, ROCHA DESTANIE R, SMITH WILBUR R,CONWAY CHRISTOPHER JEFFREY,
<br /> CAMACHO MARCO, LENZ GREG,HUSS SCOTT P, HOGAN JOSEPH DANIEL,BERG BERNARD I,J AND J ,
<br /> ANAGEMENT LLC WAVERLY, DOYLE DAVID,TILL STEVEN ROBERT JR,TREVINO SELSO JR,J A R HOLDINGS,
<br /> LLC,VOGL RICHARD J,STINAR TOM,LEE JENNY L, SUN COMMUNITIES
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