Dewatering coal fines at Port Waratah with GEOTUBE dewatering containers

OVERVIEW

Port Waratah Coal Services (PWCS), located in the Port of Newcastle, operates one of the largest coal export terminals in the world. The facility handles substantial volumes of coal annually, and as part of routine operations, coal fines settle out in dedicated settlement ponds. Over time, these ponds accumulate significant volumes of coal fines in slurry form, with high water content that complicates removal, transport, and disposal.

In 2025, PWCS undertook a major clean-out of one of its primary settlement ponds to maintain operational efficiency and meet environmental compliance requirements. The objective was to extract and dewater the coal fines in a manner that was both cost-effective and environmentally responsible. Given the scale and complexity of the operation, PWCS engaged Dredging Systems, a specialist contractor in slurry handling and dewatering, to deliver a complete solution.

Dredging Systems selected GEOTUBE^® dewatering technology as the preferred method for this project. The GEOTUBE system has a proven track record in industrial and environmental applications, providing efficient separation of solids and water while being scalable, adaptable, and easy to deploy in challenging operational environments.

CHALLENGE

The coal fines in the PWCS settlement pond were present as a high-water-content slurry. Transporting this slurry directly would have been costly and inefficient due to the excessive weight and volume. In addition, high moisture content poses environmental challenges during disposal and increases the risk of spillage and contamination.

Mechanical dewatering methods, while available, can be costly to operate and maintain, and they often require significant infrastructure and energy inputs. The project therefore required a solution that could:

• Handle large volumes of fine particulate slurry efficiently.

• Reduce moisture content to minimise weight and volume for transport and disposal.

• Operate within a confined terminal environment without disrupting port operations.

• Ensure full compliance with environmental regulations and avoid adverse impacts on surrounding infrastructure or ecosystems.

Given these constraints, the dewatering method needed to be highly efficient, relatively low-impact in terms of site footprint, and capable of producing consistent, reliable results under strict operational controls.

SOLUTION

Dredging Systems mobilised a high-capacity dredge pump to extract the coal fines slurry directly from the settlement pond. The slurry was pumped through a dedicated pipeline to a series of strategically placed GEOTUBE containers in a prepared laydown area. This location was designed to allow controlled drainage and ensure proper containment of solids.

To enhance the dewatering process, an in-line flocculant polymer dosing system was used during pumping. The polymer promoted rapid coagulation of fine coal particles, improving solids retention within the GEOTUBE units and significantly accelerating water release through the woven geotextile fabric.

The dewatering process was carried out in a controlled manner over several weeks. As slurry filled each GEOTUBE unit, clear water drained out through the geotextile walls. This water was collected for reuse within the facility or for safe discharge back into the terminal’s treatment system, ensuring environmental safeguards were always met.

The laydown area design was critical to the system’s success. It ensured that drainage water was properly captured and directed, preventing uncontrolled runoff and protecting surrounding infrastructure. Throughout the operation, Dredging Systems closely monitored polymer dosing and GEOTUBE dewatering performance, adjusting as needed to optimise results and maintain consistent dewatering efficiency.

By the conclusion of the project, thousands of cubic meters of slurry had been processed. A substantial proportion of the water content was removed, reducing the overall mass and volume of the dewatered coal fines. This reduction directly lowered transport and disposal costs while making handling and storage safer and more manageable.

The entire operation was conducted within strict environmental guidelines, with no reported incidents or negative impacts on the port’s operational capacity. The use of GEOTUBE dewatering technology not only provided a cost-effective solution but also demonstrated superior environmental performance compared to conventional mechanical methods.

The successful completion of this project reinforced the advantages of geosynthetic dewatering systems in large-scale industrial applications. It highlighted the operational flexibility, scalability, and reliability of the GEOTUBE dewatering solution in managing fine coal sediments and set a benchmark for future sediment management strategies at Port Waratah.