Wet Dust Suppression

Water Suppression

While the sprinklers are not on at the moment of the photograph, large amounts of standing water are visible at the Dominion Terminal.

Coal dust emissions in Southeast Newport News and Lambert's Point are primarily managed using wet suppression methods that consist of spraying water, or water with chemical additives, over coal storage piles, railcars, and/or transloading equipment using a system of sprinklers and water trucks. Water application is often adjusted based on terminal activity and ambient humidity conditions.

History in Hampton Roads

Water suppression is mentioned in the record as early as the 1920s, when the Chesapeake and Ohio (C&O) Railroad Company installed a custom pipe system to spray water on coal-filled railcars where and when the cars were emptied through overturning. Following an air monitoring study in 1956 demonstrating coal was a major portion of airborne dust in Southeast Newport News and pressure from the Newport News City Council, C&O installed equipment to create a water fog over the coal piers to suppress dust.

Following community pressure on politicians and complaints to Virginia Air Pollution Control Board and additional research in the 1980s, water suppression infrastructure was expanded in Southeast Newport News and Lambert's Point, Norfolk. According to the Virginia Department of Environmental Quality (VA DEQ), the new water suppression system at the terminals in Southeast Newport News reduced coal dust emissions by 80%.

Today

Despite decades of dust control using water suppression, nearby residents continue to report that coal dust negatively impacts local air quality, outside and in their homes, leaves dust films on outdoor and indoor surfaces, harms quality of life, and requires residents and property owners to bear high air filtration costs. That said, it is commonly held that coal dust pollution in Southeast Newport News was worse before the water suppression sprinkler system was upgraded in the 1980s. Residents also describe seeing sprinklers that are frequently off. There are also reports from residents that the sprinklers are not turned on until winds are very fast.

The Dominion Terminal now used 79 sprinklers, turned on about four times per day or more depending on the weather, as well as a water truck dispatched to locations not covered by the sprinklers. The Kinder Morgan Bulk Terminals use a system of 44 sprinklers to spray water that suppresses dust emissions from the piles and transloading equipment. In 2022, Kinder Morgan spokesperson Amy Baek claimed the Kinder Bulk Morgan Terminals used 20,000 gallons of water every hour to suppress dust emissions.

Water suppression is argued to be effective at fairly low cost. The terminals in Southeast Newport News and Lambert's Point have fought against other dust mitigation methods, not because they do not work, but because of their associated price tag, even though costs are small as a fraction of the terminals' annual revenue.

Chemical Coatings

In general, dust suppressants should be durable, protective, easy (meaning they do not significantly impede transportation processes), cost-effective, and non-toxic.A variety of formulas are on the market, including oils, waste oils, oil emulsions, latex sealants, lignin derivatives, polyacrylamides and proprietary formations, each with their own drawbacks.

Many private companies offer chemical sprays that coat the coal with a sealant that prevents fugitive dust emissions. This does not work on storage piles that must be moved frequently.

According to a representative from Norfolk Southern, most coal-carrying rail cars are sprayed with chemicals when they leave the coal mines, minimizing the dust emissions en route to terminals.

Water‑based sprays

• Plain or mist water sprays are commonly installed at conveyor transfer points, rotary dumpers, hoppers, and stockpiles. They rely on fine water droplets (typically 10–200 µm) to adhere to dust and settle it out of the air oizom.com.
• Mist cannons or Dry Fog systems generate ultrafine droplets (<10 µm) to form an airborne “blanket” that agglomerates dust in enclosed areas like hoppers and tipplers amsj.com.au+1oizom.com+1.
• Surfactant‑enhanced sprays: Addition of surfactants reduces water surface tension to improve adhesion to fine, hydrophobic coal dust. This method enhances capture efficiency and conserves water compared to plain sprays globalroadtechnology.com+4oizom.com+4reddit.com+4.
• Foam suppression: Foam mixes water, air, and a foaming agent to create a lasting layer that traps dust at high‑impact zones (e.g., conveyor ends, crushers) with minimal moisture addition oizom.com+1dustsafetyscience.com+1.

Chemical sealants and binders

• Products like Nbco DustBind, DustBind Plus, DustLock, HAUL‑EZE, and HAULAGE‑DC are polymer or salt-based additives applied via spray. They form a flexible crust over coal to prevent wind erosion and self-heating, especially during rail transport and stockpile storage .
• Case: Nalco’s flexible sealants withstand rail vibrations and weather without hard cracking .

Mine‑to‑terminal chemistries

Programs like Veolia’s CoalPlus and PowerTreat apply blends of antioxidants, binders, and foam (“body‑feed”) at the loadout stage. These reduce coal oxidation, hot‑spot formation, and spontaneous combustion risks, especially in sub‑bituminous coals globalroadtechnology.com+6watertechnologies.com+6watertechnologies.com+6.

Application in railcar loading & unloading

• Railcars are sprayed with polymer coatings post-loading and mid-route to form crusts; after unloading, exteriors are washed to prevent dust migration neptuneterminals.com.
• During unloading (rotary tipplers or bottom dumps), spray manifolds activate to create full‑car spray curtains, reducing fugitive emissions reddit.com.

Emerging technologies

• Hydrogel-based suppressants (e.g. itaconic-acrylic polymer + bentonite) show ~9× efficiency increases over plain water and reduce water use by ~90% pubs.acs.org.
• IoT‑enabled systems integrate dust sensors, wind data, and automated controls to optimize chemical application only when needed oizom.com.

Concerns

Some of the chemicals are environmentally toxic and present potential problems if spray run-off and spillage is allowed to fall onto ground unprotected by a collection pad.

Documents

• Railroads of Port Adopt Coal Sprinkle: Growing demand for Sprinkled Coal Said to Be Made by Trans-Shippers, Daily Press, November 23, 1927
• Ohio Office of Air Pollution Control, Reasonably Available Control Measures for Fugitive Dust Sources (Part 1), September 1980
• Ohio Office of Air Pollution Control, Reasonably Available Control Measures for Fugitive Dust Sources (Part 2), September 1980
• Ohio Office of Air Pollution Control, Reasonably Available Control Measures for Fugitive Dust Sources (Part 3), September 1980
• Ohio Office of Air Pollution Control, Reasonably Available Control Measures for Fugitive Dust Sources (Part 4), September 1980
• City Planning Commission Meeting Minutes, City of Newport News, May 2, 2018
• Email Correspondence between Richard Posner of Dust Solutions, Inc. and Repair Lab Team Member, 2023
• Repair Lab, Coal Dust in Southeast Newport News is a Nuisance and There Are Solution (Corrected), August 2024
• Wituschek E. et al. Coal Dust Control: Recommended practices for loading, unloading and transporting coal by rail. Regional Report No. 86-17. April 1986.