U.S. Department of Transportation
Federal Highway Administration
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Washington, DC 20590
Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
This magazine is an archived publication and may contain dated technical, contact, and link information.
|Publication Number: Date: July/August 2000|
Issue No: Vol. 64 No. 1
Date: July/August 2000
In 1999, the North Carolina Department of Transportation (NCDOT) decreased landfill waste by nearly 4,000 tons (3,628 metric tons) through recycling and waste-reduction activities. These efforts yielded nearly $50,000 through the sale of recycled materials and saved the department more than $500,000 in disposal costs.
Though the cost-savings and the positive effects on the environment are significant, NCDOT is also working to demonstrate the cultural benefits of recycling to help encourage more local participation. With this aim, NCDOT has created innovative programs that add value to local communities as well as to the state. From reusing local landmarks to providing building materials for low-income families, the department's recycling efforts are preserving the state's natural resources and are enriching communities throughout North Carolina.
The mission of NCDOT's Resource Conservation Program is to improve markets for recycled products. The program, which is led by conservation engineer Marie Sutton, also oversees the department's recycling activities, measuring the value and reporting the results.
|NCDOT conservation engineer Marie Sutton showcases the wide range of materials made from recycled products at last year's N.C. Project Green technology fair. (credit N.C. Department of Transportation)|
Sutton stresses that conservation is a collaborative effort. For example, an information exchange between Sutton and the value engineering staff, which studies product performance and cost-feasibility, gives both sides valuable insight.
"Working alongside engineering analysts provides the perfect opportunity to introduce new materials," said Sutton. "I also look to them for guidance on how the final cost of a project will be affected by the addition of recycled products."
Critical assessment of the department's recycling efforts is a necessity for Sutton, as the use of recycled materials is not always the most cost-effective method of construction — at least not in the short term. Due to the success of NCDOT's recent work, however, there is solid evidence that recycling is getting "greener" in terms of cost-recovery, as well as environmental sustainability.
Since the Resource Conservation Program was established eight years ago, Sutton has gained much knowledge about which materials perform best in highway construction. She recently put her experience to the test on a section of Raleigh's much-awaited Outer Loop, which was completed in December 1999. The project employed the widest use of recycled materials by NCDOT to date. Contractors who bid on the project were required to base their bids on the use of recycled materials; a list of which was provided by Sutton.
The length of the project — three miles (five kilometers) — made it a perfect candidate for an extensive use of numerous recycled products. Nineteen tons (17.2 metric tons) of tire chips (about 1,900 tires) were tilled into the embankments to help aerate the soil. Products made from recycled plastic were installed throughout the project, including 2,800 guardrail offset blocks, 2,500 fence posts, and 270 flexible delineators.
The project also used donated materials. Coal fly ash was donated by local power companies to mix with concrete to stabilize 1,350 linear feet (410 meters) of sign posts. The city of Raleigh donated 260 tons (236 metric tons) of municipal sludge to the department to use in place of agricultural limestone fertilizer, saving the department $15,000.
The use of recycled products added just a quarter of 1 percent to the final cost of the project. Since this project's contract was awarded, 10 more contracts with recycling specifications have been awarded for highway construction.
NCDOT is also working to incorporate the use of recycled products in departmental expansion projects — an effort that has proven to be measurably cost-effective. Recently, the Charlotte maintenance yard replaced traditional stone with more than 200 tons (182 metric tons) each of steel slag and crushed glass to stabilize a portion of the work yard and to provide backfill and drainage around three sides of a new storage building. The crushed glass was provided by the Mecklenburg County Recycling Center at no cost, and the steel slag was purchased at a cost of $4.50 per ton (per 0.907 metric ton) compared to $7.65 per ton of stone aggregate. The use of recycled materials yielded a total savings of more than $2,250.
Bridging the Past
When bridge demolition is required, this work is usually awarded to the contractor responsible for building the replacement bridge. As part of the contract, NCDOT retains items such as traffic equipment or aluminum guardrails for use in future construction projects. The remaining materials are then disassembled and hauled away by the contractor. Some parts of the bridge may be recycled, such as the expensive steel reinforcements that form the framework of the bridge, but the majority of the materials usually end up in the landfill.
A recent demolition project, however, is setting a new standard among the contracting community. McLean Contracting of Baltimore, Md. — the firm awarded the contract to demolish the 48-year-old John Lawson Bridge in New Bern, N.C. — is showing some creative alternatives to traditional demolition. McLean, which also builds bridges and performs general marine construction, will reuse the steel beams for a crane support platform during the construction of a new pier for the U.S. Navy. The majority of the other materials will remain within the community of New Bern. The bridge deck, for example, is being crushed and sold to a local company specializing in the production of driveway stone. The concrete caps, wooden pilings, and the bridge tender's house are being sold to local residents for private use.
According to George Bosmajian, vice president of McLean Contracting, landfill fees are becoming cost-prohibitive.
"To keep our costs low, we've got to look outside traditional landfills for the disposal of demolition debris. For projects like the John Lawson Bridge, it's simply more economical to sell the materials for reuse rather than transport them to a landfill," said Bosmajian.
Recycling local landmarks adds value to communities such as New Bern, which is famous for its picturesque scenery.
"The John Lawson Bridge has been a vital part of New Bern's history for as long as I can remember," said NCDOT assistant resident engineer Freddie Criscitiello. "Reusing the bridge in other settings is not only environmentally sound, but it also helps our community retain an important link in our cultural heritage."
|Motorists visiting NCDOT's 62 rest areas and welcome centers will find recycling receptacles for most types of waste.|
There are feasible alternatives to demolition, especially for the state's historic metal truss bridges. Established in 1978, NCDOT's Bridge Relocation and Reuse Program helps communities retain and sometimes relocate these local landmarks for use elsewhere. For example, a bridge in Stokes County was moved by a private group to Glencoe Mill Village in Alamance County. In its new location, the bridge is used by pedestrians and bicyclists to cross a stream. Since its inception, the program has preserved 26 bridges throughout the state.
NCDOT recently proved that older building materials not only stand up to new construction, but they can also complement historic communities, such as Old Salem, a restored 18th-century Moravian settlement. In December 1998, the department opened the Old Salem Pedestrian Walkway with a bridge that was built using reclaimed timber. Sources include early 20th-century industrial buildings in North Carolina and Virginia. The oldest timber was salvaged from the harbor at Savannah, Ga., where it had been used as piling for more than 200 years. A picture of this popular "new" landmark in Winston-Salem was featured on the cover of the 2000 edition of the state's transportation map to help encourage environmentally friendly construction.
Right of Way
Recycling is not traditionally associated with right-of-way acquisition. However, thanks to a new partnership between the NCDOT division office in Durham and the Habitat for Humanity of Wake County, selected homes located within the department's rights of way are getting a new lease on life.
Instead of demolishing these homes through traditional methods, which can pollute the air and increase landfill waste, the department permits Habitat for Humanity to partially disassemble them and store the materials in Habitat's reuse center. Materials salvaged include wood flooring, carpeting, cabinets, doors, windows, and appliances. These items are used in new construction for low-income families or resold by Habitat to the general public at reduced prices.
So far, three homes within the department's right of way in Holly Springs have been partially taken apart by Habitat, diverting a total of 4,000 pounds (1.8 metric tons) of demolition debris from the landfill. Due to the success of this program, other NCDOT division offices are planning to partner with local Habitat groups across the state.
"In addition to the economic and environmental benefits of our partnership with NCDOT, there are numerous social benefits as well," said Scott Skrypek, Habitat's "deconstruction" manager. "The partial deconstruction of these homes was completed by volunteers, many of whom are working toward building their own homes. Community involvement in the deconstruction and reuse process helps demonstrate to the public the value of recycling."
A New Face for Old Signs
Until recently, the process for reusing the green, regulatory signs along the state's highways was anything but "green." In the past, the procedure for removing the old lettering stripped the sign of its chromate conversion coating, which is necessary to retard corrosion. The application of the chromate is an environmentally unfriendly process that would have to be repeated to recycle the sign. However, through a new partnership with the state Department of Corrections, highway signs will now be recycled using a more environmentally sound system.
In January 2000, the Department of Corrections awarded a contract to Hydrostripper of Fergus Falls, Minn., for the purchase of a state-of-the-art, high-pressure water system, which is being installed at a sign reclaiming plant in Carthage. Inmates of a Carthage correctional facility will recycle the signs using the new system, which will not damage the aluminum, allowing the sign to be reused over and over again. In addition to the environmental benefits, NCDOT expects to save about $250,000 per year, using this new system.
As one of the state's largest employers, NCDOT is a significant generator of solid waste. In response to growing amounts of waste, the department has stepped up its recycling and waste-reduction efforts. In 1997, NCDOT received the Governor's Award for Excellence in Waste Reduction in recognition of the department's achievements. Last summer, employees throughout NCDOT participated in training provided through N.C. WasteWise, a voluntary program promoting waste prevention, recycling, and the purchase of recycled materials by businesses, nonprofit organizations, and state agencies.
In addition to recycling office waste, the department is also proactive in reducing waste generated in the field. The ferry division recycles recovered bilge oil, used engine oil, brass, copper, steel, and other metals from operations at the shipyard. The rail division recycles lead acid batteries, oil filters, and used oil during maintenance work. The department's motor fleet reuses antifreeze, recycles lead acid batteries and motor oil, and retreads vehicle tires. In addition, NCDOT and the N.C. Department of Corrections created a training program for inmates to repair electrical, pneumatic, and hydraulic tools used in NCDOT's operations.
The department is also committed to helping motorists recycle. In 1998, 70,000 pounds (31.75 metric tons) of recyclable waste was collected from rest areas. The waste was sorted and transported to collection centers throughout the state. To help streamline collection and encourage public participation, NCDOT added recycling containers to its 62 rest areas and welcome centers. Motorists may now sort all types of recyclable waste, including clear glass, green glass, brown glass, aluminum, plastic, and newspaper.
Educating the Public
Investing in the environment is important, but the department is also providing outreach and public education activities to ensure that citizens have the knowledge they need to take care of their world.
NCDOT is a member of N.C. Project Green, a partnership created by Gov. Jim Hunt to encourage environmental sustainability in state government. In July 1999, NCDOT participated in a technology fair held in Raleigh, sharing its environmental efforts with other state agencies. Exhibits included recycled products, alternative fuel vehicles, and wildflower displays. This year's event, NC Clean & Green 2000, was open to the general public, as well as to state agencies, with the participation of local universities.
Members of N.C. Project Green are encouraged to create annual environmental plans to demonstrate their commitment to the project. One of NCDOT's plans includes the construction of a "green" rest area off of Interstate 40 in Clyde, N.C. The project will replace an existing older facility, and it is intended to showcase "best practices" in environmentally friendly construction. The rest area, which is currently under design, will be built using recycled materials and will feature the application of alternative energy technologies. Locating the facility in such a heavily traveled corridor will give thousands of visitors — from throughout the state and beyond — the opportunity to see for themselves that recycled products do serve as viable construction materials.
For Sutton, sharing the department's work with the public gives her great satisfaction.
"Transportation touches everyone," she said. "Using recycled products in transportation projects is one of the best things we can do to prove to citizens that NCDOT is working to preserve our state's precious natural resources. And if they see that we care, maybe they'll care more, too."
Ashley T. Memory is a public relations officer with the North Carolina Department of Transportation. She serves on the advisory panel of N.C. Project Green, an interagency association dedicated to environmental sustainability in government, and she is a member of the North Carolina Association of Government Information Officers. Her work has also recently appeared in North Carolina Wildlife. She has a bachelor's degree in English from the University of North Carolina at Chapel Hill.