Most construction and household debris is fine. The limits come from Colorado's disposal rules and from what the receiving site will take.
Colorado bars several things from any solid waste site. As the state health department sets out, lead acid batteries, used oil, liquid waste or waste with free liquids, waste tires and waste electronic devices and computers are all prohibited from disposal in a solid waste facility. Televisions, monitors and computers have to go to an electronics recycler instead.
Hazardous waste, paint, solvents and fuel cannot go in a standard container either. Douglas County takes household hazardous waste and electronics by appointment at its own site, and that is the right route for those items.
Soil and rock deserve a separate mention here. They are allowed in a container but they are extremely heavy, and a load of dirt or scoria will reach its weight limit long before the container is full. Tell your account manager if dirt or rock is part of the job so the right size and weight allowance go on the order.
Yard waste is best kept out of the main container. The County accepts brush, limbs, grass, leaves, sod and pine needles from residents at its own drop-off site, but it refuses lumber, stumps, roots, fencing, pallets, railroad ties, wood with nails and construction debris, and it does not accept contractor loads at all.
If you are not sure whether an item belongs in the container, ask your account manager before it goes in.