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News Releases from Region 02

EPA Takes Action to Protect Benner Bay and Mangrove Lagoon in St. Thomas, U.S.V.I. from Water Pollution

Mariendahl Quarry Complex Ordered to Comply with the Clean Water Act

Contact Information: 
John Martin (martin.johnj@epa.gov)

(New York, N.Y. – November 3, 2016) The U.S. Environmental Protection Agency (EPA) has ordered the owner of the Mariendahl Quarry Complex and related industrial areas in Estate Mariendahl, St. Thomas, to address its discharges of stormwater and wastewater. The stormwater and wastewater flows into the Turpentine Run Ghut, which flows into Benner Bay and Mangrove Lagoon. The Mariendahl Quarry Complex, which is owned by Heavy Materials, LLC, has been out of compliance with the Clean Water Act since at least July 2013, when the EPA and the Virgin Islands Department of Planning and Natural Resources inspected the complex. The facility currently has no stormwater management infrastructure in place and is unable to process all of the wastewater generated at the quarry and ready-mixed concrete production areas. Heavy Materials is the largest producer of ready-mixed concrete and masonry blocks in the U.S. Virgin Islands.

“The types of wastewater that runs off of these facilities can be caustic and can seriously damage water quality," said Carmen Guerrero Pérez, the Director of the EPA’s Caribbean Environmental Protection Division. “It is imperative that this company comply with the Clean Water Act in order to protect sensitive ecosystems in St. Thomas. The EPA will address the issue of civil penalties.”

The Mariendahl Quarry Complex has a number of industrial activities, including quarry mining, stone crushing and processing, ready-mixed concrete production, and masonry block manufacturing, which involves the use of gravel and sand products also produced at the facilities.

The Clean Water Act prohibits the discharge of process wastewaters without a permit. The law also requires industrial facilities, such as ready-mixed concrete plants, and sand and gravel facilities, to have controls in place to prevent pollution from being carried into nearby waterways during rain events.

Each business must have a stormwater pollution prevention plan that outlines guidelines and the most effective management practices that the company will follow to prevent runoff from being contaminated by pollutants.

Stormwater from ready-mixed concrete plants often has a very high pH and contains oils, greases, and high levels of suspended solids. When these solids settle they can form deposits on the bottom of the water bodies that destroy plants and animals and the spawning grounds of fish.

The EPA has ordered Heavy Materials LLC to undertake the following actions to come into compliance with the Clean Water Act:

  • Fast track implementation of measures and controls to reduce the amount the unauthorized discharges;
  • Within 60 days, prepare a Comprehensive Project Implementation Plan that will include topographical surveys and a Hydrology and Hydraulic study that will show where stormwater could enter and be discharged from the complex and its related facilities into the ghut;
  • Within 60 days, conduct an engineering analysis that will include an evaluation of all potential pollution sources, an evaluation of best management practices in place to address the potential for discharges of pollutants from wastewaters, and an evaluation of storm water discharge outfalls. The engineering analysis will also include applications for the appropriate discharge permits of the complex. The discharge permit procedures will be handled by the Virgin Islands Department of Planning and Natural Resources (VIDPNR), which is the permitting authority in the USVI;
  • Within 90 days, establish a corporate Environmental Compliance Management Program, that will be used to implement Clean Water Act and permitting requirements at the complex; and
  • Preparation and submittal of monthly progress reports to notify the EPA and VIDPNR of the actions taken and to be taken to comply with the order and the Clean Water Act.

Heavy Materials LLC has begun complying with several provisions of the order that were either required immediately or within 30 days. The EPA is focusing on bringing the Mariendahl Quarry Complex into compliance with the Clean Water Act.

For more information on stormwater discharges from industrial facilities, visit:


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