Built on a headland, it services the Moonee and Chain Valley underground mines, with all production shipped 35km to the Newcastle coal handling facilities aboard the MV Wallarah, a purpose-built self-unloading bulk coal carrier.

ONDEO Nalco says the application of its Dust-Ban 81610 dust control agent to the site's network of unsealed haul roads has virtually eliminated dust problems generated by truck movements, ensuring that airborne dust readings are well under EPA limits.

Specifically developed for suppression of ultra-fine dust particles on unsealed roads and similar surfaces, Dust-Ban 81610 is a non-toxic, organic surface-active agent. Diluted up to 1:2500 by volume in water, it agglomerates the particles by reducing the surface tension of water, thereby improving the wetting and penetration properties of the dust suppressant solution.

Catherine Hill Bay's ongoing dust monitoring program had earlier indicated an increase in airborne dust levels from increased road haulage from the fine coal storage area and access road. To avoid creating dust problems for employees and local residents, mine management identified dust suppression as a matter of priority.

”The problem of the increasing dust levels had to be solved with a viable, long-term solution," Bruce Black, Catherine Hill Bay preparation plant maintenance/shipping manager, said. "After looking at a number of alternatives ONDEO Nalco was contacted to provide their expertise and a possible product."

A long-term supplier of flocculants and coagulants to COAL Australia, ONDEO Nalco Australia Pty Ltd arranged for a trial of Dust Ban on the Catherine Hill Bay site.

"The product was initially supplied in 200-litre drums and manually added to the site's 20,000-litre water tanker," said ONDEO Nalco regional sales engineer Steve Kelly said.

Fully approved following a two-month trial, Dust Ban is now bulk stored on site and automatically dispensed using a bulk pack and metering pump assembly also provided by ONDEO Nalco.

"Dust Ban is now used on all unsealed roads at the Catherine Hill Bay site," Kelly said.

Black said that prior to the trial the unsealed roads were being watered every four-to-six hours. "They are now sprayed with Dust Ban every 12 hours on dry, hot days or less as the weather dictates and easily cope with upwards of 100 truck movements in an eight-hour shift," he said.

Recent results from the site's five dust monitoring stations show that dust levels are well under acceptable limits and overall site watering is more cost-effective now the unsealed roads are only treated on average every 12 hours.