Ballast water is essential for large vessel operations, but it is a primary cause of the spread of invasive aquatic species around the world. Harmful aquatic species and pathogens can survive a long transit and quickly multiply into pest proportions when released outside their native habitat. Organizations and governments worldwide, including the US Coast Guard and EPA, have issued strict requirements for the treatment of ballast water before it can be released near shore.

Global and Glosten utilized a mobile system to treat ballast water on board a 350-foot cargo barge for aquatic nuisance species. The Ballast Responder is a mobile system used for treating a ship’s ballast tanks, killing potential aquatic invasive species and rendering the ballast water ready for discharge. Glosten had developed the Ballast Responder mobile system in cooperation with the US Geological Survey and the National Park Service; previous deployments had been performed to gain efficacy data and establish treatment protocols. The treatment of the cargo barge marked the first time the Ballast Responder system was used in a live deployment to assist a vessel requiring ballast water management.

The small footprint of the system and ease of setup make it highly mobile and ideal for emergency response situations. The Ballast Responder delivers a sufficient dose of biocide – in this case sodium hypochlorite (bleach) – and uniformly mixes the dose throughout the tank utilizing submersible pumps and spray nozzles. After a carefully monitored dosage and residence time, followed by sample testing and redosing with additional biocide if needed to ensure efficacy, the successfully treated tank is then neutralized with sodium thiosulfate. After treatment with the neutralizing agent, crews again conduct tests to ensure the ballast water is with the proper parameters. The team used the Ballast Responder system to successfully treat all 3,990 tons of ballast water in the vessel’s six tanks.