Case Study

Defined water savings measure delivers on the additional benefits of reduced dust.

Client: NTC Contractors
Value: 22.5ML of water saved per annum pro rata over 3 months
Location: Pilbara Region, WA
Date: October 2012

Above Image: Untreated haul road, experiencing a significant dust cloud.

Above Image: The treated road shows significant improvements.

Project Description

The project is located at one of Australia’s largest LNG projects, off the North West Shelf in Western Australia. The client determined the most feasible location for its onshore processing plant was approximately 10Km from an established township. Part of the initial feasibility study included transporting seawater from the nearby town to aid in the management of vagrant dust. As the project is in a highly sensitive ecological area, project managers and operators are keen to reduce resource consumption and management of water is a significant challenge. The proximity to the township and a commitment to good citizenship in the area, means that dust control is a priority.

Challenges

The most readily and consistently available water source is seawater, which is transported from the nearby township. At the commencement of the project, the site was using approximately 95,000L per day, with a number of areas not yet under construction. The water was having a measureable impact on managing dust in areas that were in use and/or under construction. However the area also included significant sections that had been cleared, but were not yet under construction. The low quality water often does not allow for effective miscibility with other liquids, and therefore many dust suppression products are unable to be effectively applied.

As the project is of such significant scale, with a number of multi-national organisations involved, stringent procedures and authorisation processes have been required to ensure all impacts are considered. The structures and responsibilities of these organisations provided a number of challenges in getting the right information to the right people.

Investigations

Laboratory and field testing on a number of water and soil samples were conducted to show the viability of DustBloc as an effective solution to reduce vagrant dust. The results of these tests showed that the seawater mixed thoroughly with DustBloc, and therefore no variation from the standard water application process would be required. The results of the road material testing showed DustBloc treated samples held their form during testing. This suggested the materials successfully bind with DustBloc.

Following these tests a three month trial was commissioned. The trial included sections of access roads, haul roads and broad acre stabilisation. In order to be considered successful, the trial needed to deliver the following results:

  • Water consumption reduced by 60%; and
  • Dust emissions reduced, and any visible dust not exceeding one metre high.

Solution

NTC Contractors, together with their clients, acknowledged the following results:

  • Achieved a reduction in the amount of water used for suppression by 68%;
  • Established dust management on all treated areas.

From this the customer issued a direction to continue the DustBloc programme, and extend the application to all areas that are subject to:

  • Heavy plant traffic;
  • Light vehicle traffic;
  • Haul roads;
  • Cleared broad acre areas; and
  • Any area where vagrant dust may impact the town or neighbouring operations.

Outcomes

Conservation

The client acknowledged a significant reduction in water consumption and associated water transportation activities. This is a measurable Key Performance Indicator for the project with the Government of Western Australia.

Occupational Health and Safety

The significant reduction in the amount of dust, as well as the height of any remaining dust provides all users within the operation, as well as its neighbours, a number of benefits, including:

  • A reduction in respirable dust;
  • Increased visibility; and
  • Decreased irritations caused from vagrant dust.

Environment

The significant decrease in vagrant dust directly correlates to a decrease in wind erosion. The product, nor its application, has raised any environmental concerns in this sensitive ecological area.