Thurston County Mineral Lands Project Planning Commission Meeting May 17, 2017 Joe Dragovich, L.G., L.E.G. Project Manager, Senior Geologist Associated Earth Sciences Inc.
Proj ojec ect O Overvi view
Proj oject ect P Purpos ose Identify, classify and designate mineral resource lands of long-term commercial significance in Thurston County
Th Thurston C Cou ounty G y Geol eology y
Geologic S Setting o of Resou ources ces Three resource geo-settings: • (1) Glacial al Outwash—Vasho hon R n Recessio ion n (2) Glacial outwash Vashon Advance (3) Volcanic Bedrock Example (right) braided river • deposits
Geologic M Mapping ng o of Thurston C n County Brief Geology • Overview—Aggregate and Rock! Volcanic bedrock • formations noted VASHON • CONTINENTAL GLACIATION
Aggreg egate R Resou ource a ce and C Conti tinen ental Glacia ciatio ion ( (18-10ka)
North-South th C Cartoon oon Cross S Sect ectio ion Bedrock old volcanic uplands. • Note the volcanic flow beds and the general scale. Vashon Advance outwash • deposited during ice advance and under the till. Vashon Recessional outwash (our • Qgo friend) deposited during ice recessional and IS THE MAIN RESOURCE. Qgo is typically thin!
Qu Quater ernary Glacia cial l Outwas ash ( (unit Q Qgo)
Brai aide ded R d River De r Deposits i in O Outwas ash P Plains ns
Data Sou a Source ces an s and Classification T Table
Data Source Notes Major Thurston County (TC) geologic map compilation TC GIS geologic map compilation and metadata derived from DGER information TC subsurface data (improved from USGS and other datasets) TC subsurface data compilation Sources of TC active mine dataset LidAR imagery Used to update geologic mapping of resource areas particularly where only 1:100,00-scale geologic mapping exists. Covers all of TC Information Washington State Department of Natural Resource 24k and 100k geologic mapping covers the TC Division of Geology and Earth Resources (DGER) 24k and 100k geologic mapping of TC for the DGER subsurface database Large dataset with wells, borings and geotechnical studies (some with sieve data). Information covers much of TC and includes DOE water well reports, geotechnical reports and other information Thurston DGER mine database Active and inactive permitted mine database including reclamation plans DGER Shelton quadrangle resource study Covers the northwest corner of TC County DGER Pierce and Lewis County Resource studies Adjacent resource studies consulted DOT mine information including reclamation plans, cross sections, drilling logs, Washington State Department of Transportation (DOT) active and inactive mine database Mineral Database of borings along major highways DOT subsurface database DOT aggregate and rock quality database Aggregate and bedrock quality data (sieve, LA abrasion tests, etc...) United State Geologic Survey (USGS) topographic 7.5-minute topographic maps of the TC with mine with pit, mine and quarry Resource maps location information USGS geohydrology study of Thurston County of Variety of surface and subsurface information including subsurface data, cross Droost and others (1998, 1999) sections, etc…. covers most of the county Lands USGS geohydrology geology and geohydrology study of Variety of surface and subsurface information including subsurface data, cross Thurston County of Walters and Kimmel (1966) sections, etc…. covers most of the county Associated Earth Science Inc. (AESI) project Provides additional surface and subsurface site specific information including Project information resource quality and quantity information at various site across the county including sediment sieve analysis at several sites Miscellaneous Geologic Publications Examples include Lea (1984) and Globerman (1981) TC thesis studies
DRAFT Table 1. Thurston County Mineral Resource Lands Aggregate Quarry Rock Classification System Sand and Gravel Resource Strata Non- (Aggregate) decreasing resource quality Resource Quality Type A 1 Quality Type B 2 Quality Type C 3 Quality Type D 4 • <5 percent fines 5 • Up to 15 percent fines 5 • Up to 25percent fines 5 • Generally Decreasing resource thickness and volume • 70:30 to 30:70 sand and gravel ratio • 70:30 to 30:70 sand and gravel ratio • 70:30 to 30:70 sand and gravel ratio unsuitable for Quantity • >25 years’ life expectancy • >25 years’ life expectancy • >25 years’ life expectancy extraction Type 1 • Minimum 240,000 yd 3 /acre • Minimum 240,000 yd 3 /acre • Minimum 240,000 yd 3 /acre • >25 percent • >100 feet thick • >100 feet thick • >100 feet thick fines 5 , may have • Minimum overburden • Minimum overburden • Minimum overburden high organic • <5 percent fines • Up to 15 percent fines • Up to 25 percent fines content • 70:30 to 30:70 sand and gravel ratio • 70:30 to 30:70 sand and gravel ratio • 70:30 to 30:70 sand and gravel ratio • Out of 70:30 to Quantity • 10 to 25 years’ life expectancy • 10 to 25 years’ life expectancy • 10 to 25 years’ life expectancy 30:70 sand and Type 2 • Average 80,000 to 240,000 yd 3 /acre • Average 80,000 to 240,000 yd 3 /acre • Average 80,000 to 240,000 yd 3 /acre gravel range • 50 to I00 feet thick • 50 to 100 feet thick • 50 to 100 feet thick • No life expectancy • Overburden <15 feet thick • Overburden <15 feet thick • Overburden <15 feet thick • <15,000 yd 3 /acre • <5 percent fines • Up to 15 percent fines • Up to 25 percent fines • Limited depth • 70:30 to 30:70 sand and gravel ratio • 70:30 to 30:70 sand and gravel ratio • 70:30 to 30:70 sand and gravel ratio Quantity • Life expectancy variable, generally <10 years • Life expectancy variable, generally <10 years • Life expectancy variable, generally <10 years Type 3 • Average 15,000 to 80,000 yd 3 /acre • Average 15,000 to •80,000 yd 3 /acre • Average 15,000 to 80,000 yd 3 / acre • Thickness varies, typically <50 feet • Thickness varies, typically <50 feet • Thickness varies, typically <50 feet Quarry Rock 6 Quality Type A Quality Type B 13 Quality Type C 7 Quality Type D 8 (Bedrock) • Formation generally well mapped and (or) high • Formation mostly divided locally and contains a • Formation mostly divided locally and contains • Generally Decreasing interbedded resource strata percentage of formation contains resource high percentage of resource strata of type B a high percentage of resource strata of type C unsuitable for strata of type A extraction 8 • Meets WSDOT specs for some rock products • Rock will not meet WSDOT specs • Meets or exceeds WSDOT specs for all rock • >30 percent waste • Fractures vary from minor to very prevalent 9 • Highly fractured 9 rock Type 1 10 products • Up to 10 percent waste rock • 10 to 30 percent waste rock • Highly to very highly • Minimal rockery-size material produced 10 • Minimal amount of fractures 9 • 20 percent or less rockery-size material produced 10 fractured 9 and (or) • Minimal percent waste rock weathered and (or) • 20 percent or more rockery- size material produced poorly lithified • No rockery - Type 2 11 None • Formation undivided 12 and >50% of formation • Formation undivided 12 and >50% of size material contains mostly resource strata of type B as formation contains mostly resource strata of produced defined for Type 1 bedrock type C as defined for Type 1 bedrock • Formation undivided 12 and <50% formation • Formation undivided 12 and <50% of contains mostly resource strata of type B as formation contains mostly resource strata of Type 3 11 defined for Type 1 type C as defined for Type 1
Inven entor ory M Map
Example Q e Quads DRAFT DRAFT Tumwater and Lacey • Leg egen end Green = Sand & Gravel • Brown = Bedrock • White = Non-County Land • Grey = Other Land • Red Outlines = Existing • designated mineral lands and mining activities
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