Aggregate Resource Availability in the Conterminous United States, Including Suggestions for Addressing Shortages, Quality, and Environmental Concerns

5 Purpose and Scope . 6 Introduction.7 Presentation Outline . 11 Where Aggregate Occurs . 12 Sand & Gravel.12 Crushed stone.13 Limestone . 14 Granite . 15 Trap . 16 Other.17 Where Aggregate is in Limited Occurrence . 18 High Plains, Nebraska . 19 Colorado Plateau and Wyoming Basin, Northeastern Arizona . 25 Non-Glaciated Northern Plains, Northeastern Wyoming . 33 Glaciated Midwest, Iowa . 38 Coastal Plain & Mississippi Embayment, Louisiana . 42 Quality, Societal, and Environmental Issues Limiting Aggregate Availability . 46 Quality Issues – Agua Fria River, Phoenix, Arizona.47 Quality Issues – South Platte River, Denver, Colorado . 52 Quality Issues – Florida . 59 Environmental Issues – Southwest Indiana . 65 Societal Issues – Permitting – Southern California . 68 Quality Issues – Minneapolis/St. Paul, Minnesota . 75 Societal Issues – Encroachment – Minneapolis/St. Paul, Minnesota . 77 Summary.81 References Cited.83 Abstract One-third of America‘s major roads are in poor or mediocre condition, and over one-quarter of the bridges are either structurally deficient or functionally obsolete. A 70-percent increase in annual aggregate production may be required to upgrade the transportation infrastructure. Natural aggregate is widespread throughout the conterminous United States, but the location of aggregate is determined by geology and is non-negotiable. Natural aggregate is in short supply in the Coastal Plain and Mississippi embayment, Colorado Plateau and Wyoming Basin, glaciated Midwest, High Plains, and the nonglaciated Northern Plains. A variety of techniques have been used to overcome local shortages, such as the use of substitute materials, recycling, and importing high-quality aggregates from more distant locations. Although potential sources of aggregate are widespread throughout the United States, many sources may not meet certain physical property requirements, such as soundness, hardness, strength, porosity, and specific gravity, or they may contain contaminants or deleterious materials that render them unusable. Encroachment by conflicting land uses, permitting considerations, environmental issues, and societal pressures can prevent or limit development of otherwiseOne-third of America‘s major roads are in poor or mediocre condition, and over one-quarter of the bridges are either structurally deficient or functionally obsolete. A 70-percent increase in annual aggregate production may be required to upgrade the transportation infrastructure. Natural aggregate is widespread throughout the conterminous United States, but the location of aggregate is determined by geology and is non-negotiable. Natural aggregate is in short supply in the Coastal Plain and Mississippi embayment, Colorado Plateau and Wyoming Basin, glaciated Midwest, High Plains, and the nonglaciated Northern Plains. A variety of techniques have been used to overcome local shortages, such as the use of substitute materials, recycling, and importing high-quality aggregates from more distant locations. Although potential sources of aggregate are widespread throughout the United States, many sources may not meet certain physical property requirements, such as soundness, hardness, strength, porosity, and specific gravity, or they may contain contaminants or deleterious materials that render them unusable. Encroachment by conflicting land uses, permitting considerations, environmental issues, and societal pressures can prevent or limit development of otherwise