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Now Incorporating Aggregates Manager



After a Long Track Record of Success Creating Products for the Roofing Industry, Specialty Granules Has Now Become a Full-Line Aggregates Producer.

Justin Bushneck


Primary and secondary crushing



Moving material at the quarry face and at the plant.

A Maryland-based company that found business success up on the roof by manufacturing granules used to make shingles, is now looking toward even greater success with a full line of aggregates products.

Specialty Granules (SGI) is an operating subsidiary of Standard Industries, a global, diversified holding company with interests in roofing and waterproofing, aggregates, insulation, solar and related investment and real estate businesses.

SGI has four production plants strategically located nationwide, maintaining a commitment to service based on an in-depth understanding of customers’ needs and an ability to translate that knowledge into innovative products.

At the company’s Blue Ridge Summit, Pa., operation, the community’s rich mining history goes all the way back to the late 1800s, when a seam of copper was found, according to Site Manager Justin Bushneck. “Copper never became a profitable mining product at this site, however a hard greenstone was identified, and they found it was perfect for roofing granules,” he said.

Built in 1923, the site employs more than 150 people from the local area today. The facility contains an open pit quarry that mines meta-basalt rock, which is crushed and screened to produce raw granule production feedstock. These raw granules are then either converted into colored roofing granules or headlap, uncolored granules used on the unexposed section of shingles.

The site also manufactures back-surfacing material for shingle underlay. A new back-surfacing plant constructed in 2014 has enhanced the manufacturing process of that product. The facility has seen continued growth through significant investments made in the quarry, mill, coloring plan and product storage areas of the business. The plant ships its products by truck and rail to customers ranging from the Northeast all the way to Texas.

Beginning as a surface operation, the site went underground for a span before returning to its original form. Roofing granules were the site’s only product until the company began evaluating its land and deposits with an eye toward producing construction aggregates.

Starting from Scratch

“In 2015, we began preliminary discussions about getting into the production of aggregates,” said SGI President Justin Dunlap. “Mellott Company did some preliminary crushing for us in 2017, and we sent off material to be tested. Those tests were favorable, so we contracted with them to produce material for a whole season to gauge the market. After those results came in, we saw a promising opportunity and decided to invest in our own plant and equipment, and operate it with our own employees.”

In developing a plan to produce aggregates with its own equipment, SGI continued to work with Mellott. The Warfordsburg, Pa.-based company designed a plant able to fit SGI’s most important needs: flexibility and achieving necessary throughput and tonnage.

“We looked at track plants, modular and portable units, and collaboratively we came up with a portable design that worked well,” Bushneck said. “One of our goals was to be able to produce #7s and #8s for asphalt in Maryland and Pennsylvania, so it was important that the plant was able to achieve the highest efficiency for those, yet still make other products.”

After deciding on a direction, a purchase order was issue for the new plant in January 2018. The plant was up and running by August 2018.

The Production Process

Production at SGI’s Blue Ridge Summit, Pa., aggregates operation begins with blasting at the quarry face, which is contracted out. They are working several quarry faces at a time, mining a hard phyllite, a meta-basalt high-friction stone.

A Caterpillar 990K front-end loader fills Caterpillar 775 haul trucks to move product from the quarry face a half-mile to a muckpile near the plant. From the muckpile, a Caterpillar 988 loader feeds the all-electric aggregates plant.

The first stage of production starts with a Metso C120 jaw crusher and the product goes to a Terex Simplicity 6- x 16-ft. scalping screen. From there SGI scalps off 2As, but also has the ability to make R3 or R4 stone. Everything else goes over to a custom-built 12- x 15-ft. portable bin.

A Superior Patriot 300 cone crusher is then used for secondary crushing and conveys to a MC300 cone plant, with a horizontal screen and crusher on one chassis. SGI uses another Superior Patriot 300 cone crusher there, and all of the oversize goes to the tertiary crusher, while the undersize and fines go a Terex Simplicity triple-deck horizontal screen for finishing, where SGI makes #7s, #8s, #9s and #57s.

At the plant, the company also uses a number of conveyors and 36-in. x 60-ft. stackers, along with a NESCO dust-suppression system to keep airborne material to a minimum.

“Right now, we are running at about 300 tph,” Bushneck said. “We do have the capability to go up to 450 tph depending on the products we want to make.”

It takes only three people to operate the actual plant: one loader operator at the primary, one person who does general labor around the plant and one equipment operator at loadout.

The plant is also equipped with cameras and sensors that transmit information to a web-based program, allowing the plant to be monitored remotely.

As long as the temperature is above freezing, the plant operates. “Our market area is Pennsylvania, Maryland, Virginia and West Virginia,” Bushneck said. “We meet state specs for all of those states.”

“I am extremely proud of our entire SGI team and how they handle all of the challenges of our industry. Their desire and drive to explore manufacturing of new products, and the commitment to operating with high internal standards that keep safety and the environment at the forefront, is a critical aspect of our success and ability to continue growing,” said Dunlap. “All of our operating locations have received industry recognition from a number of agencies over the past several years. We’re particularly proud of the awards we’ve received from the National Stone, Sand and Gravel Association for environmental excellence, as well as two Gold Sterling Safety Awards since 2016 for the lowest total injury incidence rate in our category.”

Technical Center

SGI’s headquarters and Technical Center are located in Hagerstown, Md. Renovated in 2016, the Technical Center’s R&D laboratory is a state of the art facility dedicated specifically to mineral roofing and aggregate materials.

The Technical Center services all of SGI’s manufacturing locations and monitors daily baserock feeds at each plant to ensure they meet demanding specifications for performance, durability, and environmental impact. Every production run of colored granule product is also included in SGI’s extensive weathering program and tested to ensure quality specifications are met.

In addition to Hagerstown, the company has plants in Annapolis, Mo., Ione, Calif., and Pembine, Wis.