This fact sheet is provided primarily for construction contractors involved with excavating footings, basements, utility trenches, road bases and other types of excavation. When excavating, solid or hazardous wastes may be encountered due to the presence of pre-law landfills, unknown illegal dumps or legally disposed of residential waste buried on an individual’s property. This fact sheet provides information and guidance regarding the proper handling and disposal of solid waste uncovered during excavation activities.
Before starting excavation, make the required call to the Missouri One Call System, 800-DIG-RITE. Missouri law requires that any person making or beginning any excavation notify all underground facility owners/operators who may be affected by the excavation at least 48 hours, but not more than 10 working days in advance, except in the case of emergency.
Missouri law defines a “working day” as every day, except Saturday, Sunday or a legally declared local, state or federal holiday. Missouri One Call Operators are on duty 24 hours a day, seven days a week.
It is also wise to find out as much as you can about the property in order to anticipate any problems and reduce the potential to put workers or the community at risk. If you encounter buried drums, bags, cans, sacks or soil that appear to contain, or be contaminated with hazardous materials, contractors should cease construction activity. We suggest you make your first call to the local fire and emergency authorities and your second call to the Environmental Emergency Response 24 hour spill line at 573-634-2436 (CHEM) to report the discovery and to receive additional direction on how to properly manage the material(s). Some characteristics of hazardous materials are unusual odors, soil staining and sometimes the presence of free product.
During excavation activities, you may uncover the following types of residuals:
- Clean fill
- General solid waste
- Hazardous waste
Management requirements differ for each of these waste types. If prior knowledge exists of a pre-law landfill, illegal dump or legal dump planned for excavation, the department’s Solid Waste Management Program (SWMP) must be contacted prior to the excavation for determination of proper handling and disposal of uncovered wastes. Contact the SWMP at 573-751-5401.
Clean fill is “uncontaminated soil, rock, sand, gravel, concrete, asphaltic concrete, cinder blocks, brick, minimal amounts of wood and metal and inert solids, for fill, reclamation or other beneficial use” [§260.200(4), RSMo].
Minimal means the smallest amount possible. Excavated material containing a minimal amount of wood, metal or other solid wastes, and thereby clean fill by definition is not regulated and may be reburied in the same location or elsewhere on the property from where it was excavated.
Concrete containing wire mesh or rebar is considered clean fill provided exposed rebar is first removed to the maximum extent possible in order to prevent a public nuisance or health and safety hazard.
Roofing shingles, sheet rock, lumber or other construction and demolition (C&D) wastes are not clean fill. When excavated material contains more than minimal amounts of these C&D or other solid wastes, all of the excavated material must be properly disposed of using the guidance in Section 2., General solid waste.
General Solid Waste
General solid waste includes nonhazardous (C&D) wastes as well as garbage and refuse. General solid waste must be disposed of at a permitted landfill or transfer station once it is excavated. It may not be dumped, burned or reburied (except at a permitted landfill) to avoid violating the Missouri Solid Waste Management Law and regulations, as well as the Missouri Air Conservation Law.
Note: When C&D waste is discovered during excavation, workers need to be aware of the potential presence of asbestos containing materials and other types of hazardous materials. Previously demolished buildings may include asbestos containing materials (ACM) in the waste.
Asbestos can be found in ceiling or floor tiles, insulation or soundproofing on ceilings, pipes, ductwork or boilers, or on the outside as transite siding or in shingles. If these materials are handled improperly tiny fibers can be released into the air, which can be harmful to construction employees and landfill operators. For information on handling and proper disposal of ACM, contact the department’s Air Pollution Control Program at 573-751-4817. If the ACM is to go to a landfill or transfer station, contact the facility in advance to see if they accept ACM and if they have any special handling or packaging requirements. For more information about asbestos requirements, see Asbestos.
Hazardous waste is any waste or combination of wastes listed in federal regulations that may pose a threat to the health of humans or the environment. The universe of hazardous wastes is large and diverse. Hazardous wastes can be liquids, solids, contained gases or sludges. Some hazardous waste, such as mercury and dioxins, may be released as gases or vapors. Hazardous wastes can be the byproducts of manufacturing processes like cyanide salts, solvents or lead dust, or simply discarded commercial products like cleaning fluids or pesticides. In regulatory terms, a hazardous waste is one that is defined by federal regulations. It could be a waste listed in the regulations by name or by the industrial process that created it or a waste that exhibits at least one of the following four characteristics: ignitability, corrosivity, reactivity or toxicity. Mixtures of certain types of wastes can compound the hazard.
If contaminated soil or waste containers are discovered, workers should withdraw to a safe distance and notify their manager before proceeding. The manager should contact the appropriate state regulatory officials and environmental professionals to safely identify the exposed waste materials and develop a course of action that meets regulatory requirements, allows the site to be safely investigated and the hazards to be removed.
You may obtain additional information about properly managing excavated wastes from the sources listed below. Environmental publications are also available at Publications and Fact Sheets.
- Kansas City Regional Office 816-251-0700
- Northeast Regional Office (Macon) 660-385-8000
- St. Louis Regional Office 314-416-2960
- Southeast Regional Office (Poplar Bluff) 573-840-9750
- Southwest Regional Office (Springfield) 417-891-4300
Additional considerations and sources
Solid waste requirements are found in the Solid Waste Management Law in sections 260.200 through 260.345, RSMo, and the regulations in Code of State Regulations, Title 10, Division 80. Hazardous waste requirements are found in the Missouri Hazardous Waste Law in Sections 260.350 to 260.430, 260.500 to 260.550 and 260.565 to 260.575, and the regulations in the Code of State Regulations, Title 10, Division 25. The state regulations incorporate and references many of the federal regulations in the Code of Federal Regulations, Title 40, Parts 260 to 280.
Printed copies of the Revised Statutes of Missouri are available through the Reviser of Statutes at 573-526-1288. Printed copies of the Missouri Code of State Regulations are available through the Missouri Secretary of State at 573-751-4015, or are available online.
To report a discovery of hazardous materials
First contact your local fire and emergency authorities, then the Missouri Department of Natural Resources’ spill line at 573-634-2436 (CHEM).