Noise concerns muffled

Mining coal is an around the clock operation with mines working 24/7 to efficiently produce the commodity

But with more mines being developed around high population areas, the impacts of mining activities can often be a contentious issue in the community.

One mining operation in the NSW mid-western region is working to be proactive in dealing with community concerns, and this month unveiled a variety of measures to minimise the impacts that noise from the mine has on the local community.

Moolarben Coal, located 45 kms north-east of Mudgee, has been operating for three years and knew from early in the development phase that minimising noise impacts is an important part of the mine’s profile.

At a recent mine site visit, the company told Australian Mining it was operating within noise compliancy conditions but continued community feedback prompted further research into ways to improve the levels of noise coming from the mine.

Moolarben sent people out into the community at night to further investigate the noises coming from the mine.

Luke Bowden, environment and community relations manager at Moolarben, said the investigations into noise produced live data coming back into the site so it could be correlated with what operations were happening at the time.

“After a time we came up with the key source of concern with banging and crashing noises which was the first pass loading activities,” he explained.

“We could have sat on our laurels and said to everyone ‘we’re complying easily with our conditions we don’t really need to act on this’, but we didn’t do that, we thought, no, there is a problem, the community is telling us there are issues, what can we do about it?”

To this end the company teamed up with Komatsu and Duratray to implement a solution for its 218 tonne truck fleet that would help to reduce noise impacts.

Duratray provided Moolarben with a specific design body which reduced loading noise while still maintaining truck efficiency.

Unlike regular truck bodies, Duratray’s suspended dump body is designed to reduce loading noise, with all trucks fitted with non-standard sound attenuated kits provided by Komatsu.

During trials a Duratray body was retro-fitted to a Komatsu 830E haul truck in late 2012.

Not only did the new bodies reduce loading noises by up to 10 decibels, but it was found that payloads were also increased, improving productivity and efficiency at the mine.

The bodies are able to carry 20-27 metric tonnes -more than the mine was producing before -reduces vibration jarring for the operator and reduces spillages.

Duratray’s SDB is comprised of rubber wall and floor liners, the floor is supported by elastomeric ropes that are connected to a steel frame. These materials dampen the noise when rock is dropped into the tray.

Moolarben Coal general manager John Blanning said the seven-month trial was a success.

“The initial Suspended Dump Body trial successfully delivered a notable measurable benefit of noise reduction during loading of adverse hard rock materials,” he said.

With the success of the first trial the company invested $2 million to purchase four new SBDs to fit the fleet of Komastu haul trucks.

Dubbed the ‘stealth fleet’, Blanning said the new trucks, set to start operation at the mine in the coming weeks, would set a ‘new benchmark’ for environmental noise reduction impacts on the community.

The new range of trucks commissioned by Moolarben is just one step in a holistic approach to reducing noise at the mine.

The company has also employed four full-time noise monitoring staff who report back to the mine with real-time data around noise levels.

Bowden said the employees react to noise alarms, complaints from the community, and are out there every night with noise monitors tracking the mine operations.

“It has reduced the negative feedback from the community and helped the EPA out a lot as well,” Bowden said.

“Operating as a mine between two other mines means there is a lot of cumulative noise emanating from all sites but having people out in the community means Moolarben is able to better understand what noise issues are coming from our site and react or adjust accordingly.”

Bowden said the tracking of mining equipment with GPS is another management technique being implemented to reduce the impacts of noise.

“We have just put GPS equipment into all our trucks,” Bowden explained.

“What we can do now is see the trucks live so the people out in the field can use tablets to spatially track the trucks and be aware of what part of the mine they’re operating in and what noises they’re making.”

Another technique being implemented at Moolarben is a daily predictive noise model which is aimed at better understanding how daily operations may affect noise levels in the local community.

“Obviously you do noise modelling for a project to get your approvals but this tool is a daily noise model where we set up all our permitters and variables that sit behind the model and the production assistants can key in the variables for what the shift is going to do, so they will key in the climatic conditions, key in where the trucks are operating, hit a button and it will spit out the predicted noise impacts within the community and will have those noise contours,” Bowden said.

“We will have a fair idea where any issues are going to come from on any given day.”

Moolarben open cut mine manager, Bruce Birchall said engaging with the local community and being proactive is essential when operating in any community.

“A lot of our people are local, I actually grew up in Mudgee,” he said.

Birchall said some groups tended to make a lot of noise about mining activities but that solutions went much deeper than simply stopping mining activities.

“Miners understand how to solve problems,” he said.

“We have a very good team here at Moolarben who are in the community and working every day to minimise impacts.”

A spokesman for the NSW Minerals Councils said the million dollar investments being implemented at Moolarben to help ease community concerns around mining showed the ways in which mining companies were listening and responding to concerns.

“There are some great things happening at our mines NSW,” he said.

“We’ve got some of the world’s best miners in this state and this new product is just one of the hundreds of examples of the innovation and technology that’s being developed and used at our mines.”

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