- Special Waste Home
- Cement Kiln Dust
- Crude Oil and Gas
- Fossil Fuel Combustion
- Mineral Processing
Frequent Questions About the Criteria for the Safe and Environmentally Protective Use of Granular Mine Tailings known as "Chat"
EPA is proposing mandatory criteria for the beneficial use of chat from the tri-state mining district in transportation construction projects that are carried out, in whole or in part, using federal funds. EPA also is proposing criteria for the beneficial use of chat in non-transportation, nonresidential concrete and cement projects. This package is called the chat rule.
The Safe, Accountable, Flexible, and Efficient Transportation Equity Act of 2005 requires EPA to develop criteria for the use of chat in transportation construction projects and cement and concrete projects. While EPA is the appropriate party to assess the environmental risks in the beneficial use of chat, the Agency is consulting with US DOT throughout the development of these criteria to ensure that the materials are structurally sound for transportation projects.
Chat, a local term for mining waste, is a lead/zinc mining waste from the tri-state mining district. Chat, also known as granular mine tailings, is composed of chert-like material, containing lead, zinc and cadmium contaminants. The tri-state region covers approximately 2,500 square miles and includes parts of Ottawa County, Oklahoma; Cherokee County, Kansas; and Jasper and Newton Counties, Missouri.
When left exposed to the environment, the lead in chat can be a hazard to human health. Chat particles can enter soil, surface water, groundwater, and air. Exposure to lead has been known to cause learning disabilities and damage the human immune, blood and nervous systems. Children are the most susceptible to these effects.
Chat can be used safely when its particles are encapsulated in asphalt or concrete. Asphalt and concrete bind chat in a solid mixture so its particles are unlikely to be spread by wind or water.
Chat from the tri-state area will be used in hot asphalt mix or concrete for transportation construction projects, such as roads and bridges. Chat may also be used in non-transportation, nonresidential concrete and asphalt projects.
The transportation bill enacted by Congress in August specifically calls for EPA to address chat from the tri-state mining district. As such, the proposed rule will impact only chat currently located in the tri-state mining district because chat located in this area is geologically and chemically similar.
No, EPA is not addressing the beneficial use of chat from any other mining districts because the transportation bill only requires EPA to develop criteria for the beneficial use of chat from the tri-state mining district.
This rule will minimally affect the local tribes. The Bureau of Indian Affairs (BIA) has initiated a process to allow chat sales from tribal lands. This rule will clarify the environmentally protective uses of chat in transportation construction and in cement and concrete projects. Chat sales destined for other uses are unaffected by this rule.