Advanced Surveys, 20 Armory Rd, Prince Frederick, MD 20678, US

Vulcan Materials Company provides infrastructure materials and is one of the United States largest producers of construction aggregates and is also a leader in the production of other construction materials. The company s construction materials segment produces aggregates, primarily crushed stone, sand and gravel, that are used in nearly all forms of construction. In particular, large quantities of aggregates are used to build roads and nonresidential properties. Vulcan Materials has more than 356 aggregate production and related facilities serving more than 20 states, the District of Columbia and Mexico. The company has more than 162 stone quarries, 29 sand and gravel plants, 67 sales yards, 39 asphalt plants and 23 ready-mixed concrete facilities. The company has more than 9,000 employees and has locations throughout the United States, including Lorton, Va.

A Weathermaster Co.

Tri County Aire

Joseph Greenwald & Laake PA

Health Care Enterprises