Limited space, unlimited significance

Every landfill has a lifespan. And in localities with limited land, strategizing that space makes sense—from economics to geography. This couldn’t be more true for the state of Hawaii, an isolated area of islands with only so much space, says Steve Joseph, vice president of operations and permitting at PVT Land Co., Nanakuli, Hawaii, on the island of Oahu.

“Our problem is we have limited land. If you think it’s hard on the mainland, it’s twice as hard over here,” Joseph says of maintaining the company’s landfill.

PVT Integrated Solid Waste Management Facility is Oahu’s only construction and demolition (C&D) landfill, where the vast majority of the state’s construction and development work takes place. In summer 2014, the company incorporated a new reclamation and recycling system for C&D debris.

Each day, trucks offload about 1,775 tons of C&D debris—mostly wood, metals and concrete—at the 135-acre facility. Joseph says about half of the debris entering the facility is processed into feedstock, which will be used as fuel by Oahu power generators.

PVT’s recycling system can process 800 tons of feedstock per day from C&D debris. Energy producers will burn the feedstock to create synthetic gas while other yet-to-be-determined gasification and waste-to-energy facilities will use it in other applications, such as for jet fuel, Joseph notes.

Joseph says importing oil can be a “real drain on the economy, so any way we can replace oil with renewable energy sources not only keeps more money in the local economy, but it also has the additional benefit of producing jobs.”

Joseph says his job entails considerable planning for the future and that the idea of converting C&D debris into a renewable energy resource has been a goal of his and the company’s for more than a decade.

He explains how leaders at PVT have historically taken the “long view” in business decisions by looking ahead. “Everyone who sits on the board is in their 60s; we’re making plans that are beyond just us.”

Joseph says he gives a lot of credit to the PVT board for making such a large investment in recycling equipment “where the return is after you retire when things start to pay off.”

Lucky for PVT, the return on its investment can potentially come more quickly since it already has a large inventory of material sitting in its landfill. The company plans to dig up much of what it has buried in its landfill over the last two decades.

Joseph estimates about 4 million cubic yards of C&D debris buried in PVT’s landfill is recoverable.

Beginning in 2016, PVT plans to use excavators to reclaim and process or reuse or recycle up to 80 percent of that C&D material. “We’ll have a portable screener up there to screen it as soon as we dig it up, and we will retain the dirt because we will use that for cover in the future,” Joseph describes. These efforts are expected to stretch the life of the landfill out by 30 years.
 

Forward thinking

Prior to PVT Land introducing its recycling system, Oahu contractors didn’t have many options for recycling, Joseph says. While some C&D firms would recycle metals and wires from different projects, admittedly, “a lot of stuff got buried,” Joseph recalls.

Some of the material buried in PVT’s landfill that it plans to reclaim includes: a 40-foot ship, whole spools of wire and 18 floors of concrete from the demolition of an office building and the adjoining shopping center.

Much of what is recovered will be processed as feedstock for fuel applications. PVT currently has 1.5 million tons of feedstock buried on-site for reserve that is covered with dirt and sprayed with carbon dioxide to preserve it, Joseph says. The company has had to stockpile its feedstock as the planned gasification facilities come online.

However, this hasn’t prevented PVT Land from recycling internally. Joseph says the company has used crushed concrete to construct interior roads and serve as structural fill under its recycling center to build it up to standards. As fill is considered a “premium” or “hard to get” in Hawaii, Joseph says, using reclaimed crushed concrete to create a firm surface on the facility’s interior roads and as structural fill has proved to be advantageous for PVT.

“We’re forward thinking in that we do all of our own construction,” he adds.

Forward thinking also comes into play with regard to how PVT plans to recover the buried C&D debris. The company has placed GPS equipment on its Caterpillar 836 compactor and other machines to identify where specific C&D debris is buried in the landfill and avoid the cell containing pure waste, such as asbestos and truck tire beads containing rubber and metal.

“Everything we never wanted to dig up again all ended up in one location, and we can recycle everything else,” Joseph explains. “As we got into this further and further we made the conscious decision to isolate anything we don’t want to dig up in one location.”

In a new conditional use permit application, PVT is seeking authorization to add additional renewable energy capacity to power its operations, including installing gasification units that will be powered by the feedstock produced on-site.

PVT also is planning to convert its heavy equipment to hydrogen fuel cell power, with the hydrogen produced on-site, leveraging the additional solar panels proposed in the conditional use permit application.
 

Rethinking recycling

While things at PVT seem fairly large today, the company started out small. “We had a much smaller system,” Joseph observes. Over time, PVT slowly incorporated pieces to increase what the company was capable of accomplishing.

About 15 years ago, PVT workers started recycling metals, which led to recycling concrete, “and then we stepped it up from there,” Joseph says. At first, the company added a short pick line with a trommel screen to pull principally metals out, he says. “That was a good learning experience on how to put the system together,” he says of the company’s trial-and-error tactics.

Joseph says PVT also worked closely with engineers from San Diego-based CP Group, which designed and installed the company’s recycling system. “Because we negatively pick, we just have to take out the things that are not feedstock; we only have to handle 20 to 30 percent of the material to have a finished product, and that was our advantage of working with our engineers in California at CP Group: how best to design the system for our purposes,” Joseph says.

While he says PVT has had much support with the addition of its recycling and reclamation system, from a state senator to the island’s construction industry as a whole, convincing the regulatory community of the modification has proved challenging.

“The challenge is a combination of changing the way people think about it and view it,” Joseph says. Getting regulators who are so used to disposal to rethink the benefits of recycling and what comes out of it involves “changing the mindset of everybody,” he says.

Joseph explains, “By recycling, even though it might be more expensive than disposal, in some areas in reality it’s not because you increase the economy by moving the material around. You have to look at the overall benefits you get out of it.” That could not be more true than when you are on an island, he emphasizes.

Many people embrace recycling, but others have a hard time accepting the change from a strictly disposal mentality, Joseph suggests. To help educate the community, PVT puts on numerous tours for schools and other interested groups to let them see the daily operations for themselves.
 

Leading the way

Joseph says PVT looks for ways it can benefit the construction industry since they make up its customer base. For starters, costs to dispose at PVT’s site are half that of the city and county landfill, according to Joseph.

For companies that request it, PVT tracks the percentage of debris that is brought to the facility and recycled for points under the U.S. Green Building Council’s (USGBC’s) Leadership in Energy and Environmental Design (LEED) certification program.

While PVT’s landfill space is limited, so too, are the job sites where contractors work on the islands. Most construction projects in Hawaii don’t have enough room on-site to include bins for separating materials, Joseph says. PVT charges an extra $2 to $3 per ton to track what materials the company recycled, which he says is cheaper than having a company employee watch to ensure the correct materials are placed in the proper bin.

Some contractors have decided that it is easier and cheaper to send materials to PVT for LEED tracking even if it isn’t a LEED-certified project, just to see what they are recycling, Joseph notes.

He adds, “We work closely with our customers who are in the construction industry and this is one of the ways we figured we could support them. There’s just not enough room at sites here.”

The author is an associate editor with the Recycling Today Media Group and can be reached at mworkman@gie.net. A version of this feature originally ran in the May/June issue of Construction & Demolition Recycling, a sister publication.