The U.S. Environmental Protection Agency has ordered the owner of the Mariendal Quarry Complex on St. Thomas to fix what it cites as problems with its stormwater and wastewater discharges. The stormwater and wastewater flows into the Turpentine Run Gut, which flows into Benner Bay and Mangrove Lagoon.
According to the EPA, the Mariendal Quarry Complex, owned by Heavy Materials LLC, has been out of compliance with the federal Clean Water Act since at least July 2013, when the EPA and the V.I. Department of Planning and Natural Resources inspected the complex.
Currently it has no stormwater management infrastructure in place and cannot process all of the wastewater generated at the quarry and ready-mixed concrete production areas, according to the EPA. 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," EPA Caribbean Environmental Protection Division Director Carmen Guerrero Pérez said in a statement.
“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," Pérez said.
The Mariendal 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 discharging wastewater 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 to:
– 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 gut;
– 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 reduce the potential for pollutants from wastewater, and an evaluation of storm water discharge outfalls.
The engineering analysis will also include applications for the appropriate discharge permits of the complex. DPNR will handle the discharge permits.
The EPA also directed Heavy Materials to establish a corporate environmental compliance management program within 90 days and submit monthly progress reports.
According to the EPA’s statement, Heavy Materials has already begun complying with several provisions of the order that were either required immediately or within 30 days.