Across the Front Range, surging economic and population growth have stimulated the construction industry.  New homes, apartment complexes and buildings are being built while older buildings are being removed or renovated.  This construction activity generates jobs, homes, and offices, but at the same time, generates a significant amount of construction and demolition (C&D) waste.  Keeping this C&D waste out of the landfill is a challenge that many communities and organizations are trying to overcome.

According to estimates, nearly 30% of the all the waste going to the landfill is C&D waste.  The most common materials making up C&D waste includes:

• Aggregates (concrete, asphalt, brick)
• Cardboard
• Shingles
• Carpet
• Drywall
• Wood (dimensional lumber, plywood, pallets)
• Scrap metal

While Western Disposal provides recycling options for some of the C&D material, there are a number of challenges that prevent more of this material from being diverted from the landfill.

Lack of Recycling Facilities.  C&D waste is commonly mixed on-site with all waste materials placed in a single container.  In order to recycle this waste, it must be sorted, much like how our curbside single stream recyclables are handled.  Facilities for sorting C&D waste, called material recovery facilities (MRFs) are prevalent in states such as California, but there are no official C&D MRFs in Colorado to sort mixed loads of C&D.  One of the main reasons for this is Colorado’s low landfill tipping fees which makes it much cheaper for mixed C&D waste to be sent to the landfill rather than processed and recycled.  Therefore, there is often little economic incentive to building facilities for sorting mixed C&D.

Colorado does have a number of private and public facilities for the recycling of some source-separated materials, such as aggregates, scrap metal, cardboard, and wood which helps divert thousands of tons of waste from the landfill every year.  However, their availability often varies by community.

Lack of Markets.  For many of the materials making up C&D waste, there are few or no markets in Colorado for processing and recycling the material.  One example is asphalt shingles.  The Colorado Department of Public Health and Environment (CDPHE) launched pilot programs across the state to create markets for converting asphalt shingles into material for road construction. However, in 2015, CDPHE adopted a policy that asphalt shingles are no longer considered a recyclable material in Colorado.  This was due to recycling facilities accepting thousands of tons of roofing shingles and then abandoning them due to lack of demand.

Separation On-Site.  As mentioned, placing all C&D waste on-site into a single container is generally the most common method of waste disposal at construction sites due to a few reasons. First, space is often limited at a construction site and only one container may fit on site.  Second, it is generally much more expensive to have multiple containers for the collection of sorted materials on site.    Finally, with multiple contractors on site during a construction project, ensuring materials are properly sorted can be a difficult job.

In spite of these challenges, for-profit companies, non-profits, and governmental entities have all sought to develop waste diversion solutions that encourage and, in some cases, require diversion from the landfill.

One example is the U.S. Green Building Council launching the Leadership in Energy and Environmental Design (LEED) certification program in 2000.  LEED provides a framework to encourage the implementation of numerous sustainability measures during construction and demolition projects.  LEED is widely recognized and has created a market for “green” buildings thereby incentivizing builders to strive for LEED certification.  One area to obtain points towards certification is waste reduction and recycling, and therefore builders seeking certification have an incentive to recycle C&D waste despite cost and sorting challenges.  Western has worked with several projects seeking this certification to ensure their waste is recycled where possible.

Local governments have also been active in trying to increase diversion.  While some local governments have sought to increase C&D diversion through general educational resources for contractors, others have enacted policy based approaches to require diversion.  The City of Boulder and Boulder County require a specified level of diversion from residential construction projects as part of their green building ordinances.  These ordinances have helped drive some diversion and increased awareness of diversion opportunities. However, enforcing these ordinances has proved challenging, which can decrease their effectiveness.

Finally, a unique aspect of C&D waste compared to other types of waste is that much of it can be reused.  Whether it is dimensional lumber, old kitchen cabinets, decorative tile or counter tops, there are organizations that have created programs and business opportunities for the reuse of C&D waste.  Resource Central (formerly Center for Resource Conservation) assists residential projects with deconstruction plans, hauling of salvageable material, and sale of salvageable material to the community at their ReSource yard at 6400 Arapahoe in Boulder.

Colorado’s economy is booming but unfortunately, so is C&D waste.  There is no denying that Colorado has significant hurdles to overcome to increase the C&D waste diversion, but it is encouraging to see both the public and private sectors developing resources and options to create more diversion opportunities.