Dust-suppression is one of Bengalla’s measures to reduce its impact on the neighbours.

A real-time environmental monitoring system and a culture that encourages sustainability saw Bengalla win a Banksia Award. Garth Lamb reports.

Mining and environmental awards do not generally go hand in hand, but the Bengalla mine in the NSW Hunter Valley is not your average operation. In 1997 it became the first Australian coal mine to receive ISO 14001 certification for an environmental management system, and this year it picked up the Banksia Award for leadership in sustainable development in the minerals industry.

Many of its neighbours were predictably unenthusiastic when the mining lease was first lodged in 1993. In a region best known for wine production, the site’s proximity to the 14,000-strong town of Muswellbrook just 4 km away saw the imposition of stringent regulatory requirements, including daytime noise below 43 decibels at L10 (10 per cent of a 15-minute period) and night time limits of 40 decibels at L1.

Mine site environment specialist Mike Chapman says a culture of sustainability throughout the workforce has been central to meeting community expectations. He says the Banksia Award proves the “Bengalla way” works.

“The guys working here have been recognised and we can demonstrate to the community that we have been trying to reach their aspirations,” he said.

Integrating sustainability
Bengalla employees learn about sustainability from day one, with economic, environmental and social responsibilities outlined in all job descriptions. In addition, bonus payments are dependent on achieving safety, environmental and production performance targets. Chapman says this is the first mine he has worked in where environmental performance counts towards his bonus.

Performance is judged through four audits a year. External contractors are brought in for a day and a half, each time focusing on a different element of operations – water management one time and dust control the next, for example. A scoring system looks at elements like community complaints, incident reports, performance against site procedures and corrective action taken by each department. Mine-wide the target is a score of 87 per cent, but every department also has its own internal target. The environment department, for example, is shooting to score 92 per cent.

If all targets are met then everyone gets their full performance bonus. Chapman claims this makes departments very keen to “lift their game”, but adds that building the Bengalla culture is not just about financial rewards. Performance updates are posted on notice boards and monthly crew meetings to keep staff up to date with procedures and training also reinforce the importance of sustainability.

Mine management has worked hard on building links to the local community. Some 67 per cent of workers live locally, including four female “clean skins” recruited during a 2002 program to encourage Hunter Valley women to become operator/technicians. While there is no official policy of employing locals, Chapman says jobs are not advertised nationally until they run in local papers.

Communication and community engagement comes through initiatives such as an annual open day that draws up to 1,600 visitors, a community consultative committee, newsletters and a schools program. In 2002 the Bengalla Community Support Team was established to manage partnerships, donations and sponsorship programs. The 12 mine employees on the team decide where the $75,000 annual budget is best spent and many volunteer their skills and time to help manage the projects.

Screen shot from the RTEMS showing information that helps keep Bengalla within regulatory guidelines.

Environment management system
A central component of Bengalla’s ISO 14001 environmental management system is a $1 million real-time environmental monitoring system (RTEMS) that collects data on weather conditions, dust levels, blast results, water management and power usage. A 90-metre tower measures air temperature at five elevations to identify inversions that could enhance noise levels, since noise is a key concern.

The RTEMS is based on a Honeywell SCADA system and the data, which is updated every 90 seconds, can be accessed by all staff via the intranet.

“We look at wind speeds and directions. If they pick up more than, say, 10 m/s wind, our operations are modified,” says Chapman. “[There is] also a network of real-time dust monitors and we can monitor our impacts and respond before concerns from the neighbours [arise].”

The four GRIMM dust monitors surrounding the site measure dust particulate sizes of 2.5 µm, 10 µm and 15 µm, and also alveolic and thoracic dust. They complement the 28 depositional monitors, which are checked every month or so, and the four high-volume air samplers that are checked every six days. While the EPA does not use data from the GRIMM monitors to evaluate compliance, the real-time data allows Bengalla to modify operations before breaches occur.

Operating restrictions on the dragline and out-of-pit dumping are enforced if wind speed exceeds 10 m/s over an average hourly period. Dust is also minimised by rehabilitating disturbed areas as operations finish and by automatic spraying of coal stockpiles with recycled water if wind exceeds 5.6 m/s.

The mine’s water balance is determined by the RTEMS, which records dam water levels and flow rates between parts of the mine. Bengalla is designed for zero discharge, with saline mine water and treated sewage used for coal processing and dust suppression.

Fresh water from the Hunter River is used only in the bathhouse and for vehicle washing and fire suppression. The mine licence allows extraction of 1,000 ML a year, but only 300 ML is required in an average year and up to 600 ML during periods of drought. Chapman expects a 2005 total of around 480 ML.

He says the Bengalla RTEMS has attracted attention from a variety of operations, including other mines, power stations and vineyards.

“Even within our own Rio Tinto Group a lot of operations want to take on board something similar,” he says. “If we can assist our sister operations, that’s fine . . . going forward that’s what the minerals industry needs to do.”

Chapman’s number one tip is to have a good IT team that keeps the system working 100 per cent of the time. The various monitors and equipment also need to be calibrated and serviced regularly, so a good support base among the on-site electricians and mechanics is handy.

Virtual tour of Bengalla at www.nswmin.com.au (education resources).