Tearing Down to Build Up
Central Environmental, Inc. provides demolition services to clients and delivers construction and demolition debris to its recycling arm, Central Recycling Services.
According to the Alaska Department of Environmental Conservation, Division of Environmental Health, the state contains more than 215 municipal landfills and more than 115 waste storage, treatment, and disposal facilities.
Recycled and reclaimed construction and demolition materials
While many communities have embraced recycling at a household level, what happens to the massive amount of debris that results from construction demolition projects?
The state faces many challenges when dealing with this issue, ranging from a lack of infrastructure to the difficulty in recycling waste from remote communities. Distance to market, economy of scale, and a lack of infrastructure have also contributed to the fact that it has taken longer for the 49th State to buy into the benefits of recycling and reclamation on a larger level—but happily, this attitude seems to be changing.
Central Recycling Services (CRS), for example, is already realizing the benefits of reclaiming materials retrieved from construction demolition projects. And end-users such as Anchorage Water and Wastewater Utility (AWWU) are discovering cost-savings and efficiencies from using the aggregates created from recycled materials.
CRS is an offshoot of Central Environmental, Inc. (CEI), which has been serving Alaska since 1984. CEI provides comprehensive services to its clients, including engineering design, construction, environmental sampling, remediation, demolition, recycling, and waste disposal.
“In 2007, CEI was the contractor for the demolition of Clark Middle School, and it was requested by the architect, general contractor, and the Anchorage School District that construction and demolition debris be diverted from the landfill as part of LEED certification,” explains Donna Mears, PE, environmental engineer at CEI. “As we began segregating the different waste streams, we realized that it wasn’t as hard as we had expected.
“At the same time, the Municipality of Anchorage was reassessing landfill tipping fees, which hadn’t been changed since 1987,” she continues. “We looked at the cost of recycling versus the increased cost of tipping fees and realized that it was possible to make this form of recycling work.”
CRS, which has a recycling facility on Railroad Avenue in Anchorage, was developed to recycle and reclaim construction and demolition materials. In the Anchorage area alone it is estimated that these materials comprise 20 percent to 30 percent of Anchorage’s waste stream. CEI is a CRS customer, as are the military and private sector contractors looking to reclaim materials from demolition projects around the region.
There are many benefits to recycling construction and demolition materials. Not only is a portion of the waste that would normally go into the landfill diverted but carbon footprints are reduced, and companies can save money by recycling materials, especially as the cost of energy and raw materials continues to rise. Companies also save on the cost of trucking goods to a landfill and tipping fees. Increased recycling is also helping to create new jobs in the recycling field and at businesses that are developing products manufactured wholly or in part from recycled materials.
Multiple pieces of equipment in action at the Central Recycling Services facility.
“More jobs are being created through recycling than the amount of jobs required to put materials into a landfill,” says Mears. “And it’s much better for the environment when we’re keeping materials active in the world instead of disposing of them; less use of raw materials means that there is less coming out of the earth to begin with.”
The numbers are impressive. According to the Institute of Scrap Recycling Industries, Inc., in the United States two-thirds of domestically produced steel is made from scrap metal recycling. Recycling 1 ton of steel conserves 120 pounds of limestone, 2,500 pounds of iron ore, and 1,400 pounds of coal. It also results in an 86 percent reduction in air pollution, 40 percent reduction in water use, and 76 percent reduction in water pollution. Use of scrap steel as opposed to virgin ore equates to energy savings of 74 percent.
Non-ferrous scrap, such as copper, aluminum, and brass, is used to make 60 percent of all alloys produced domestically, and 40 percent of the world’s copper is supplied by scrap.
How It Works
According to Mears, CRS diverts at least 75 percent of incoming construction and demolition debris to beneficial uses. This debris is delivered to the facility as a commingled load or contractors have the option to save money by further segregating loads on the job site.
As CRS’s largest customer, CEI delivers construction and demolition debris from numerous sites around the state. Some of the company’s most recent Alaska demolition projects include the Central Heat and Power Plant on JBER-Richardson, the Northern Lights Hotel in Anchorage, the Loussac Library stairs in Anchorage, and the Flint Hills Refinery in North Pole.
“Before we undertake a demolition, we do a building survey and create a work plan so that we know what types of materials we’ll be dealing with,” explains Mears. “You need to have good information going in so that you know what you’re getting into.”
For example, on the Northern Lights Hotel project, asbestos remediation was required before any demolition could take place. “From the outside, it doesn’t look like we’re doing anything for a while because we’re sampling, testing, and creating work plans for the removal of hazardous material before we can get on to the ‘glamorous’ major deconstruction,” laughs Mears. “Tearing things down is so much more impressive.”
In the case of asbestos, non-regulated tiles, if handled properly, will not become airborne, so these can be disposed of at local waste facilities. Regulated asbestos material, on the other hand, can only be shipped to specialized facilities, so it must be properly packaged and handled.
“We also create a strategy to recover metals, steel structures, and concrete because they all have a value and can be sold at market,” says Mears. “The metals go to the CRS metal yard where they are sorted and packaged and sent out of state. The concrete and asphalt stay local because we crush it down to create recyclable concrete aggregates and asphalt products.”
Become an Industry Sponsor
CRS also resells items such as I-beams, rebar, and windows and tiles for industrial projects. “We’re sort of like a Habitat for Humanity ReStore but on a more industrial level,” says Mears, adding that these goods are brokered directly to clients.
CRS’s main recycling facility holds a shredder and sort line, as well as a crusher and screens for producing aggregate. Commingled loads are processed through the shredder and sort line into components including ferrous and non-ferrous metals, plastics, wood, and gypsum. The company also uses a portable baler to make tire bales that can then be used as fill or for retaining walls.
“There are a lot of moving parts,” says Mears. “One of the biggest advantages for our clients is that we can do it all here because we run the recycling business in conjunction with the demolition business, so we are able to offer better deals.”
While it depends on the year, Mears estimates that CRS is able to keep approximately 50,000 tons of waste a year out of the landfill.
Where It Goes
CRS creates a number of aggregates that can be used in construction and road projects, including a recycled concrete aggregate, recycled asphalt pavement, and recycled glass aggregate. CEI has used the recycled glass aggregate for construction of a sewer main along Railroad Avenue, and it has also been used by AWWU on a number of projects.
“We have used CRS’s glass aggregate as bedding on four of our projects to date,” says AWWU Project Manager James Armstrong, PE, adding that the utility first began working with the company in 2012. “These include the Iris Drive sewer project in midtown Anchorage; the Northern Lights water main project, where we used it as bedding for 4,000 feet of 16-inch pipe; the Anchorage Railroad project; and the Second Avenue sewer project.”
CEI brings down a tower at the Fairbanks International Airport.
According to Armstrong, AWWU began using the glass aggregate after speaking with CRS. “They explained that a lot of contractors and engineers didn’t know about the product, so we looked into it and discovered that other states were successfully using it as a road base,” he explains. “After studying it further, we issued a memo that approved specifications for its use in our projects.”
The glass aggregate is cost-effective, as it is typically less expensive than a typical aggregate made of sand and gravel. AWWU was also able to save on transportation costs on the Second Avenue sewer project since it was near CRS’s Ship Creek facility.
Despite its success on these projects, Armstrong says that the use of recycled aggregates is still in the “toddler” stage of development, and Mears agrees. “We need more support on finding end markets for our recycled materials,” she says, adding that the glass aggregate is beginning to gain traction for use in parking lots. “We’ve had glass recycling for five to six years now, and it’s just starting to take off as a construction product, getting used in larger, more visible projects.
“One of the problems is that we’re a little behind the times in Alaska,” she continues. “Washington state, for example, began researching markets for glass in the 1990s. The other issue is that we don’t have the critical mass of materials in Alaska that other places do, so we have to be more creative. We’re always looking for new uses for our products and, right now, construction material is our market.”
Left to right: General Manager of Solid Waste Services Mark Spafford, Anchorage Mayor Ethan Berkowitz, and General Manager of Anchorage Water and Wastewater Utility Brett Jokela stand in front of the reclaimed glass that was used as pipe bedding to install 4,000 feet of 16-inch PVC water main on the Northern Lights Boulevard project.
There are a number of other recycled materials that CRS produces that are finding second uses as well. Screened, fine material that is a residual of the construction and demolition recycling process is being used as alternative daily cover at landfills, where it helps minimize exposure to weather, deter animals and insects, and mitigate fire risk.
“The old-school method of covering landfills each night was to use whatever soil was on site,” says Mears. “The problem with that is that the holes are only so big, so the dirt only provides so much cover.”
Using CRS’ ADEC-approved alternative daily cover, which contains small pieces of wood, dirt, concrete, drywall, shingles, and other components, landfills not only have enough material but can grade and compact it, just as they would soil. It is currently being used as an intermediate cover at the Anchorage Regional Landfill and Chugiak Birchwood R&SP Inert Waste monofill, and was used at Birchwood to shape slopes to create the final grade for closure.
The recycled glass aggregate material produced by Central Recycling Services has been used in water main and sewer projects; it typically costs less than aggregate made of sand and gravel.
“I think that there’s some poetry in using discarded, recycled materials instead of virgin materials for landfill cover,” says Mears.
CRS also creates tire bales and gabions, which have been successfully used as non-frost-susceptible fill for road construction at the Central Monofill Services facility in Salcha.
“Tire bales can be used to form a solid driving surface as well as for berms in landfills,” says Mears, adding that while typical landfill design provides a 3:1 side slope, tire bales are approved for monofill construction to 2:1, allowing for greater air space and preventing slopes from sloughing off over time.
While it has taken a while for the importance of recycling and reclamation to catch on in the 49th State, there’s a growing understanding that not only can businesses help preserve the planet but they can also put money back into their pockets while doing so. The key is in learning how to use waste creatively and cost-efficiently.
“It’s an obscure field,” says Mears. “In a lot of businesses, you know what you’re buying, but with recycling, you don’t know what you’re getting or where it’s coming from. It’s not always what you want, but it’s what you’ve got. The balance is in matching what comes in with where it needs to go.”
Vanessa Orr is a freelance writer and former editor of the Capital City Weekly in Juneau.
Pipe being installed on the Northern Lights Boulevard project.
In This Issue
2018 Engineer of the Year Christine Ness
Nominated by the Alaska Chapter of the National Association of Women in Construction, 2018 Engineer of the Year Christine Ness is a fire protection engineer and project manager at PDC Engineers, an Alaska-based firm with five offices and more than one hundred employees. Ness always knew she wanted to be an engineer and, after moving here in 2013, found in Alaska the happy combination of her many loves: a brilliant husband, ample opportunities for solitary fishing excursions, and the ability to pursue her passion to make the world a little more fire resistant.