County History Unearthed in Shellrock Mining Pits

By Bob Davidsson
        Unless a home in Palm Beach County was built on the Florida Atlantic Coast Ridge, odds are its subdivision rests over landfill material excavated from one of South Florida's shellrock mining pits.
        Long lines of railroad cars filled limestone aggregate are often observed passing through the Palm Beaches daily as they make their trek from the Lake Belt mines, an 89-square mile area between the Everglades and suburban areas of Miami-Dade County, to four rock distribution centers located in central and northern Florida coastal cities.
        In its promotions, the Florida East Coast (FEC) Railway reports, "We move hundreds of thousands of aggregate carloads" to the service areas along its rail.
        Limestone aggregates are used to produce cement, concrete and asphalt needed to build roads, bridges, runways, homes and public facilities. Limestone, shell and dolomite are types of marine sediment deposits formed in Florida over millions of years.
        Limestone and its aggregates is South Florida's leading mining product. About 153 million tons of rock are mined per year for Florida construction projects or for export, according to industry estimates.
        The Florida Department of Transportation, a major user of shellrock aggregates, has established specifications for its use (Section 913A). It states, "Materials used for shellrock base shall be defined as naturally occurring heterogeneous deposits of limestone with embedded layers or lenses of loose and cemented shell, to include cemented sands (Calcific sandstone)."
        "This material shall be mined and processed in a manner that will result in a reasonably homogeneous finished product," the FDOT rule states. "Approval of mined aggregate sources shall be in accordance with Section 6-3.3."
        Shellrock formations vary from unconcentrated sand to loosely compressed shells. It includes "coquina" (Spanish word for small shell) formations found in Florida coastal areas from St Johns County south to the Florida Keys.
        Limestone excavating, commonly called "rock mining" in Florida, began in the year 1672 when King Charles II of Spain authorized the construction of the "Castillo de San Marcos" fortress in St. Augustine. Locally mined Anastasia Island coquina was cut into blocks and used to build the fortress walls and internal barracks.
        Today, the "Castillo" remains the oldest European masonry fortification in the United States.
        During the First Spanish Colonial Period (1513-1763), coquina also was the building material used for Fort Matanzas (Torre de Matanzas), guarding the southern gateway to St. Augustine in 1742, and the St. Marks garrison outpost in 1753.
        One of earliest companies involved in a "rock and sand hauling" business in Palm Beach County was the Rinker Materials Corp., founded by Marshall E. "Doc" Rinker (1904-1996) as the "Rinker Rock and Sand Company" in 1926.
        Rinker provided construction services throughout Florida, including Disney World and Epcot. The West Palm Beach-based company was valued at $515 million when it was sold to CSR Ltd. in 1988. The company was the largest producer of ready-mix concrete in Florida at the time of its sale. CEMEX acquired the Rinker Group in 2007.
        The Florida Department of Environmental Protection (DEP) is the oversight agency responsible for evaluating ecological impacts and the restoration of mining sites. According to the DEP, there are currently six licensed mining sites in unincorporated Palm Beach County:

• Palm Beach Aggregates mine and expansion sites located west of the Acreage near S.R 7.
• Stewart Mining Industries - Palm Beach County Mines, northwest of the Palm Beach Aggregates.
• Fine Stone Mine - Gilbert Pit, south of the Martin-Palm Beach County line near Lake Okeechobee.
• U.S. Sugar Corp. - Lake Harbor Quarry in western Palm Beach County, south of Lake Okeechobee.
• Bergeron Sand, Rock and Aggregate's Florida Rock Quarry in western Palm Beach County.
• CEMEX Construction Materials - South Bay Quarry, located west of the Loxahatchee Refuge.

        Palm Beach Aggregates (PBA), the largest active mining operation, broke ground in 1993. The 3,000-acre site in Loxahatchee mines about 100 acres annually for fill material used in construction.
        PBA mining operations include the 2,200-acre C-51 Reservoir which stores 61,000 acre feet of water available for use as a water supply, storm water storage and flood control. Broward County and five municipalities have expressed interest in the mining reservoir as a future water source.

The History of Okeeheelee's 'Shellrock Pits'
        The name origin of Okeeheelee Park supposedly derives from the Miccosukee word "Okee-hee-the," which translates to "pretty waters, quiet waters, or good waters" depending on what information source is used.
        In truth, when the original 90-acre rock mining site was acquired by the State of Florida in 1973 for $7 million, then traded to Palm Beach County in a land swap, the waters were neither pretty, quiet nor good. The lakes were deserted shellrock pits flooded by seasonal rain.
        There is no record of native American villages at Okeeheelee. Historically, the site consisted pineland scrub forest, not pretty waters.
        The rock pits at Okeeheelee were strip mines used by construction companies during the high noon of mining in Palm Beach County during the 1950s and 1960s, a period when county production rivaled Dade's "Lake Belt".
        According to the 1968 "Mineral Producers in Florida' report, there were nine limestone and crushed rock mines in Palm Beach County operated by Belle Glade Rock Company, Douglas Shell Pit near Haverhill, Gorham Construction Company on Skees Road, MacArthur Gardens Construction Company in Palm Beach Gardens, Rubin Construction Company west of Florida Turnpike in West Palm Beach, the Chasten Powell site near Lantana Road, P.C. Smith Company, Inc. of West Palm Beach, and the W.R. Grace Company's Boca Raton vermiculite plant.
        The rock mine at Okeeheelee was owned by the Cleary Brothers Construction Company of West Palm Beach. The Cleary Brothers - President and CEO James E., Vice President John B. and Treasurer-Secretary Dennis - incorporated their architectural and construction engineering firm March 8, 1937.
        In its Florida articles of incorporation, Cleary Brothers detailed the company's mission: "To conduct and carry on the business of building and contracts for the purpose of building, erecting, altering, repairing in connection with all classes of buildings...and the laying out and construction of roads, avenues, docks, slips, sewers, bridges, walls, canals, railroads, airports, power plants and generally all classes of buildings."
        The Okeeheelee rock aggregate provided the raw material for an impressive list of Florida projects completed by Cleary Brothers Construction throughout Florida. In Palm Beach County, the Cleary Brothers were contracted to build the East Camino Real Bridge in 1939, the 540-foot Boca Raton Inlet Bridge in 1963, and a replacement span for the first Flagler Memorial Bridge in 1965.
        During World War II, Cleary Brothers were contracted for projects at Morrison Field in West Palm Beach, and the Homestead Air Force Base in 1942. Other state contracts included the 180-foot Sebastian Inlet Bridge in 1965, the St. Lucie Canal locks for the Lake Okeechobee Cross-State Canal project n 1968, and the conversion of several Flagler railroad spans into the Overseas Highway in the Florida Keys.
        The Cleary Brothers rock mine also provided landfill material for the 3,860-acre Lyons Farm site in Broward County. Coral Ridge Properties converted the infilled farmland to the planned community of Coral Springs, incorporated on July 10, 1963.
        Today, Okeeheelee is a 1,702-acre regional park operated by Palm Beach County. Where there were once rock mining pits, the county provides a water skiing course, 14 athletic fields, eight tennis courts, a golf course and a dog park. A nature center with trails opened in 1992.

Prehistoric 'Monsters' Emerge from Rock Mining Pit
        In 1969 a dragline operator digging a drainage canal at the P.C. Smith Shellrock Company quarry, known as the "West Palm Beach Site," made an unusual discovery. Florida Atlantic University was contacted by the mine operator and told  they had a "bag of bones" collected at the mine site.
        The "bag of bones" turned out to be the fossils of several species of extinct giant mammals that once roamed Palm Beach County. Archaeologist Howard Converse was tasked with identifying and removing the bones from the rock pit in March 1969. He was assisted by local college students and volunteers.
        The West Palm Beach Site was a commercial shell quarry located seven miles west of  the city's downtown in what is today the Golden Lakes community.
        The rock miners had accidently unearthed an ancient riverbed which had attracted the prehistoric animals to the site 20,000 years ago during the late Pleistocene Epoch. During their two-month excavation, the scientific team recovered 600 identified  specimens, currently housed in the Florida Museum of Natural History in Gainesville.
        The fossil remains include bison, giant capybara, dire wolves, and three species of ancient cousins of the elephant - the Colombian mammoth, American mastodon and gomphothere, an extinct species of tapir.
        Perhaps the best preserved fossilized artifact found in Palm Beach County was the partial skeleton of a 12,000-year-old mastodon nicknamed "Suzie".  It was displayed for many years at the South Florida Science Center.                                                                                                                    
        South Florida's rock mines have long been the targets of conservationists and other critics who question their impacts on the Florida Aquifer and future water supply. Without the use of the rock mining industry's aggregates, however, the infrastructure of the county - roads, housing, masonry buildings, airports - would not exist.
        Rocking mining was and remains an important part of the county's history.
(c.) Davidsson. 2018.
NOTE: Article summary and notice also was printed in The (Belle Glade) Sun. Read additional articles below and archived in Older Posts.