Any District resident will tell you, with great certainty, at the height of a turgid summer: D.C. was built on a swamp. That’s only half true. The reality is a lot more complicated.

Here’s the lay of the land: The rocky Piedmont’s rolling uplands extend west of Rock Creek all the way past Great Falls to the Appalachian Mountains. The coastal plain sprawls to the east, with sandier soils that meander into the tidal reaches of the Potomac River. The meeting point of the two zones is the most fertile ground for evidence of human occupation, hiding the remains of people who ate fish and deer that stayed close to the stream. The rest of the District is pockmarked silt and clay deposits left over from the last Ice Age. Burial sites show up under the Whitehurst Freeway and evidence of kilns has appeared on the campus of St. Elizabeths.

Soon after D.C. came into being, it got bigger. The new American government pushed fill dirt into the rivers to give its capital more space. The Ellipse in front of the White House is a trash dump in a stream valley, for example. Early on, there were always enough vacant lots nearby to dump dirt excavated from building sites.

But lately, there’s been more and more construction dirt, and not so many places to put it. After the long economic freeze of 2008 and 2009, developers are rushing to get concrete in the ground, with cranes sprouting up across D.C.’s staid skyline. Because buildings can grow no taller than 12 stories, they instead grow downwards, leading to some of the deepest parking garages in America. So yawning holes have appeared up and down 14th Street, on South Capitol Street, H Street NE, in the central business district, and in less obvious places like the Blue Plains wastewater treatment plant, where new filtration systems are being installed. In many corners of the city, you can barely walk five minutes before peering into a red dirt abyss.

Of course, something has to happen with all that soil, and there aren’t the kind of vacant dump sites in the District that there used to be. The construction boom has put contractors in a tough spot as they seek landfills further and further from the holes the dirt comes from. The dirt market, more or less, is saturated—which, for the contractors who build things in Washington, is a good problem to have.

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The most important thing to know about dirt is that not all of it is created equal.

“There are basically three types of dirt,” says Neil Stablow, a vice president at the Donohoe Companies, a construction outfit that’s now working on big digs at 2400 14th St. NW and on South Capitol Street.

The first type: “good dirt,” usually sandy soil that can be packed down and used as fill for other projects that might need to create a grade or building pad. If possible, an excavator will “tie it” to another project—in the case of the District’s 11th Street Bridge project, old concrete is being crushed up and used to build up land underneath new overpasses—but if not, construction firms try to find some other place to send it. When the Woodrow Wilson Bridge was under construction, a lot of hole-diggers sent their dirt there (bridges need to be raised up, so they pair well with projects involving parking garages). These days, the mega-development Konterra, in Laurel, Md., is absorbing a lot of dirt.

“If they have material that is usable, and then they have a place to take it, it’s all money,” Stablow says. “If it’s the cheapest thing, they find a home on another project.”

The second type: “unsuitable dirt,” which can’t be used for other projects, usually because it’s got organic material that would decompose and create problems for building on top of it. That has to be hauled off site and dumped in a landfill, like the one that’s receiving the 450,000 cubic yards of dirt from the 50-foot-deep CityCenterDC. Ten cubic yards at a time, trucks are hauling it to a big hole on Palmer Road just off Indian Head Highway in Prince George’s County.

The third type: Toxic dirt, which has been contaminated by things like petroleum leakage at old rowhouses or gas stations. That has to be taken to a special facility for remediation, like SoilSafe Inc. in Columbia, Md., which gets expensive.

Usually, an excavator will find all this out in a geotechnical report before starting work on the site. If it’s a government-funded project—such as the excavation of the Metrorail system—archaeologists can get involved to preserve what artifacts may be buried underneath. But with most private projects, the dirt just gets hauled away, and no one gets to study it first.

“Your home is your castle,” says D.C. archaeologist Ruth Trocolli, almost wistfully, of the potential historical resources just beyond her reach. “I don’t get to review every square inch of the District. That’s just the nature of it.”

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Determining what kind of dirt you have is one thing. Figuring out how to get rid of it is not as simple. The District’s dirt disposal industry has only a few main players, and competition is brutal.

Here’s how the world is divided at the moment: Goldin and Stafford, which has been around since 1992, is in charge of dirt from construction at the Marriott Marquis at 9th Street and Massachusetts Avenue NW, Sibley Hospital, Canal Park near Nationals Stadium, and part of St. Elizabeths. Strittmatter Companies, which started in 1978 and opened a local office in 2009, has CityCenterDC, Steuart Investment Company’s residential project at 3rd and H Street NE, the houses at Dakota Crossing, the National Public Radio building on North Capitol Street NE, a big housing project on 14th Street, and a residential project called NoMa West. There are a few others—like Metro Earthworks, which declined to comment—but these two do most of the work in D.C.

A few of their projects are some of the biggest dirt removal operations D.C. has ever seen. The Marriott Marquis, for example, will go so deep into the ground—95 feet—that the hole will have to be locked with concrete slabs from the top down to keep it from collapsing from the water pressure. Getting the dirt out at that point also gets tricky. While trucks can drive into big holes with dirt ramps, the last bits have to be taken out with “longstick” backhoes that reach down 40 feet. Cranes are required for anything deeper.

In order to find places to put all that dirt, the companies employ brokers who buy and sell the stuff, cutting deals at whatever price they can negotiate. “We have three guys now that all their job is to find out where dirt can go,” says John Strittmatter, owner of Strittmatter, noting that his company expects to move more than a million cubic yards of dirt this year. “You could get nothing for a load of dirt, or you could get $100. There’s really no system to it.”

That’s the thing about the dirt market: It’s far from efficient, because perfect information does not exist. Dirt exchanges operate successfully in places like Phoenix, Ariz., and Los Gatos, Calif., acting as clearinghouses that create fair prices for different kinds of fill. According to Strittmatter, there have been attempts to create one in the Washington area, but nothing’s been successful. “I don’t think we trust each other,” he says.

There’s good reason for that. If you have to find dirt for a project, you have three options. Ideally, you’re digging up dirt on another one of your own jobs that will fit the bill. If not, you can get it from a quarry; crushed stone retails for between 15 and 18 bucks a ton, or more than $600 a truckload. But if the quarry isn’t conveniently located, and a competitor has the kind of dirt you’re looking for, you might end up cutting a deal with them—even if it means paying nearly as much as you would at a quarry.

“If you’re in the position where you’re needing your competition to help finish your projects, you’re not going to survive,” says Brian Mattingly, a vice president of Goldin and Stafford. “If they feel like you’re in trouble, it’s, ‘Punish the weak.’”

The bigger problem now, though, is getting rid of dirt, since not many projects need more of it. As a safety valve, excavation companies keep their own landfills, and must use them judiciously. Holes fill up, after all, and you’re not allowed to take the dirt out again once it’s been dumped. (Although you can sometimes build on top of them; Strittmatter is working on a redevelopment deal for one of its landfills in Laurel.) Even knowing the location of dump sites can bring a competitive advantage. Mattingly tells me he’s got one landfill in Oxon Hill, Md., but declines to specify another location, figuring that his rivals could calculate his fuel costs when bidding on contracts.“If someone else knows where I can go to, they can figure out how aggressive to be on pricing,” Mattingly says. “Who drinks scotch, who drinks whiskey—you got to know what the other’s doing.”

Like all space, where dirt can be dumped is a finite resource. So excavation companies will need to keep seeking locations farther afield, adding fuel costs every year. Just like garbage, the District keeps producing dirt. Mattingly’s company worked on the redevelopment of the site of the old Capital Centre, in Landover, Md., which they first helped build in the 1970s.

“The beauty about being in this area is that it’s always changing, and there’s always a revitalization taking place,” he says. “A number of these projects that are monumental, you think are going to be around for 50 to 100 years or so. Our world’s changing so fast that 25 or 30 years is the longevity of a building.”

Photos by Darrow Montgomery

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