Q&A Column

Construction projects always generate substantial quantities of waste material. Is it feasible to separate the waste into categories for recycling? What are the costs and savings that might be realized?

Approximately 15 to 20 percent of municipal solid waste is generated from construction and demolition projects. On a typical commercial construction site in Minneapolis, the waste generated may comprise 20 to 30 percent wood, 10 to 20 percent concrete and block, 5 to 10 percent drywall, 5 to 10 percent cardboard and l to 8 percent metal, plus other miscellaneous materials. All these materials are currently salvageable and marketable within our area.

What are the costs and savings that might be realized? Currently the haulers who separate "waste" off-site are becoming more competitive with those who haul directly to the landfills. Savings that occur are:

  • extension of the life of many construction materials through reuse or recycling.

  • depending on market in a given area, some "wastes" can be revenue-generating (e.g., resale value for metal is currently very good).

  • lower tipping fees because landfills often have established separate fees for clean or separated construction/demolition materials.

  • fewer and lighter pulls. Heavier materials (concrete, metal) when sorted out allow for more space in a roll-off and an eventfully lighter unit at the tipping station.

Savings are determined by the availability of markets, prices for the materials, and the commitment of persons involved in the process.

How can this be specified?

Guides to develop waste management specifications were developed recently. These guides assist in providing language, structure and formulas for this task. Identifying the haulers and/or destinations for the recovered materials is essential. Check with your county/state recycling coordinators, solid waste management offices and local recycling centers.

Answer submitted by Glen Meyer, Resource Manager, Cunningham Group