Thousands upon thousands of years ago, eroded material from the Appalachian Mountains was carried down the Potomac River and deposited throughout the Chesapeake Bay region.
One such deposit area in what is now Prince George’s County, MD, near Washington, D.C., is known as the Brandywine formation. It contains a rich concentration of that eroded material, which over the years has become sand and gravel.
Given the building boom that’s been going on in the nation’s capital for many years, that nearby sand and gravel, a key ingredient in building products like ready-mix concrete and hot mix asphalt, has become very valuable.
About six years ago, Aggregate Industries, a worldwide provider of aggregate-based construction materials, bought approximately 1,800 acres of property in the heart of that sand-and-grave-rich Brandywine formation near Accokeek, MD, approximately 15 mi. south of the Beltway. The company’s plan was to put in a 500-plus ton-per-hour plant to help supply aggregate to the D.C.-area construction.
Because such a use requires a special exemption from the county zoning board, the company knew getting approval for the sand and gravel operation would not come quickly, and it didn’t. Eventually, however, following a multi-year process, approval was granted and the appeals ran their course.
A company doesn’t start up a large sand and gravel operation like the Accokeek Gas Light (so called because the property was formerly owned by Washington Gas Light Company) facility overnight. It took nine months of construction to prepare the site, but by mid-May 2005, the plant, which employs 21 people, was up and running.
“As might be expected in a startup operation, there were some hiccups early on, but within a couple of months, we were meeting our production goals,” said Plant Manager Robert Wease. “As we continue to develop the property, we’ll add a conveyor system, but for now, we’re close enough to the processing plant that it’s not necessary.”
Tim Bevard, Aggregate Industries’ manager of Estates and Permitting, handled the governmental approval process for the Accokeek Gas Light project — and it was no small accomplishment.
“The Accokeek Gas Light site in Prince George’s County has been recognized as a prime piece of mining property for at least the last 30 years,” said Bevard. “The reasons are: number one, geologically, the sand and gravel is there; number two, it’s a large tract; and number three, it’s close to the Washington, D.C., metropolitan market.
“In addition to mining, there had been many other proposed uses for the property, all of which had been rejected by zoning commissions, county councils and/or residents.”
The process of getting a sand and gravel pit approved for the site started with obtaining a special exemption to allow it.
“There are many tests a company has to pass including plans to control traffic, noise, air quality and other environmental issues like wetlands and flood plains,” said Bevard.
“Adding to the difficulty, the D.C. suburbs are definitely spreading out here into what we used to consider the country. Since most people don’t want a sand and gravel operation in their neighborhood, there were plenty of obstacles to overcome.”
Demonstrating the difficulty, only one other sand and gravel plant, a similar Aggregate Industries facility in Brandywine, had been approved in the last 20 years.
“I’m sure Aggregate Industries’ long history of, and commitment to, environmentally responsible mining helped convince commissioners,” said Bevard, who added that he thought this could be the last such mining operation, or at least the last in a long time, to gain approval from the county board.
“The material we produce is definitely needed if we’re going to continue to build and grow, but there seems to be some sentiment around here to limit and control such growth in the future. Because of that, I don’t think there will be another sand and gravel/wash plant approved around here any time soon.”
World Leader in Aggregate
With corporate headquarters in Britain, Aggregate Industries is one of the world’s largest producers. It has six U.S. divisions, including the MidAtlantic group, which has operations and serves customers in Washington, D.C., Maryland, Virginia and West Virginia.
The MidAtlantic division includes two quarries and five sand and gravel plants. The sand and gravel operations, including Accokeek Gas Light, supply Gas Light, supply materials to ready-mix concrete plants and asphalt plants (Aggregate Industries’ own facilities as well as others) throughout the region. In the mid-Atlantic area, Aggregate Industries also has its own contracting group that does asphalt paving.
In addition to Bevard and Wease, key personnel involved in getting the Accokeek plant up and running included Don Delano, vice president of Aggregate Sales; Jon Brentlinger, general manager Aggregates; and Roger Kalaha, project manager.
After the company got the okay to develop the Accokeek site, it took a lot of work to make the facility operational.
“It was a heavily wooded site, so first we had to clear it and build roads,” Brentlinger noted. “Soil conditions, which basically consisted of a silty, clay overburden, were a constant challenge. We also had to dig a series of water retention ponds and establish a stockpile area for finished product.”
The Accokeek plant also is unique to Aggregate Industries in that it uses a water clarification technique in the production process.
“All the water from the plant goes into a large, 75-foot-diameter clarifying tank where we add flocculent to send solids to the bottom,” Kalaha explained. “That underflow is pumped back to the area where we’re mining the bank-run material, while the clear water overflows and is recycled right back to the plant. The advantage is that, because we’re no longer discharging into ponds, we no longer have to constantly clean the ponds and truck the mud. It reduces our fines-handling costs tremendously.”
Heavy Equipment for Heavy Work
Aggregate Industries used Komatsu equipment from Midlantic Machinery in Baltimore to help do the initial site work. That equipment now handles the overburden removal and reclamation work associated with the mining process.
The Accokeek Gas Light plant has two Komatsu HM400 articulated dump trucks, a Komatsu D155 dozer and a Komatsu D41 dozer.
Bob Mohre is the Midlantic sales representative who works with Aggregate Industries.
“The big dozer is able to move a lot of material and the operators say they really like the little dozer because it’s responsive and very comfortable,” said Kalaha, who oversaw the construction efforts. “And we’ve been very impressed with the trucks. We’re in some really soft material here and I don’t think they’ve ever been stuck.”
“The big thing for us is equipment availability, and we’ve had excellent uptime from our Komatsu machines,” added Wease. “Part of the reason for that is the equipment itself, and part of it is probably due to the fact that we have a maintenance contract with Midlantic. They do our routine machine maintenance and repairs and it’s worked very well for us. They respond quickly and have taken good care of us service-wise.”
Capacity and Customer Service
Aggregate Industries estimated it will be at the Accokeek Gas Light site for at least 15 years.
“That’s what we estimate our reserves to be in relation to the strong demand that exists for our product,” said Wease. “Washington, D.C., is a booming construction market and we certainly don’t foresee a slowdown anytime soon.
“The advantage we have over our competitors is that we have greater production capability than anybody else in the region — and we have an exceptional trucking fleet that can really deliver to our customers as required,” added Brentlinger.
“It’s that capacity and customer service that really sets Aggregate Industries apart from other aggregate suppliers in the area. And certainly, the Accokeek plant will help us meet the needs of our D.C.-area customers even more efficiently and more effectively than we’ve been able to do in the past.”
(This story appears courtesy of Midlantic Machinery “News.”)