BeneTerra designed and delivered a complete onsite treatment train that maximised water recovery, minimised haulage, and enabled full rehabilitation within a tight three-month window.

Arrow Energy engaged BeneTerra to decommission and rehabilitate six remote storage dams in the Bowen Basin.

To optimise logistics, wastewater from the six dams was consolidated into two central dams on a single site, containing approximately 5 million litres of highly saline water (equivalent to seawater). The site was located 100 km from Arrow’s nearest wastewater facility and was accessible only via dirt tracks with no services.

At a Glance

  • ~5 million litres of wastewater processed
  • ~2.5 million litres recovered as clean water and reused onsite (≈50% recovery)
  • 45,000 km of heavy-vehicle movements avoided (≈88% reduction)
  • ~2.5 million litres processed through BeneVap with ~75% volume reduction
  • Only 500–600 kL of brine required offsite transport
  • Project completed in 3 months, including full dam rehabilitation

Client Context

Arrow Energy is a major Queensland energy producer supplying natural gas and electricity across the state. As part of its land restoration commitments, Arrow is progressively decommissioning more than 50 ponds and returning each site to a productive condition for landholders

For this project near Dysart, Arrow needed to safely remove and treat wastewater from two dams and complete rehabilitation before the onset of the wet season. A key objective was reducing the number of kilometres travelled by tankers—lowering cost, environmental impact and healthand-safety exposure across its regional operations.

The Challenge

The site presented a combination of technical and logistical complexities:

  • High-salinity water: Equivalent to seawater, with algae and suspended solids.
  • Remote access: Last 8 km via dirt track, with no power, water or infrastructure.
  • Tight timeframe: Only three months to remove water, treat waste streams, dismantle dam infrastructure and rehabilitate the site.
  • Transport risk: Offsite disposal required a 100 km haul to Moranbah—representing tens of thousands of kilometres in heavy-vehicle movements

Arrow needed an integrated, field-ready solution capable of treating complex wastewater onsite while enabling safe, compliant, full-site rehabilitation.

BeneTerra was selected for its ability to combine wastewater treatment, engineering design and soil/land rehabilitation into one coordinated program.

Beneterra's Solution

BeneTerra engineered a bespoke treatment train tailored to the site’s water chemistry, salinity and recovery objectives.

  • MULTI-STAGE FILTRATION AND MEMBRANE TREATMENT
    • Coarse filtration and a 20-micron spin disc filter to remove algae and solids.
    • 500 kL/day ultrafiltration feeding a 250 kL/day two-stage seawater RO plant, recovering approximately 50% permeate—significantly higher than typical SWRO systems.

    The UF/RO system was mounted on the deck of a 45-foot semi-trailer, eliminating the need for concrete pads, sumps or foundations and dramatically reducing site establishment time.

  • ONSITE VOLUME REDUCTION USING BENEVAP

    RO brine, plus all cleaning and backwash wastewater, was processed through a BeneVap BV300 providing an additional 80% volume reduction.

    This reduced the residual brine to only 500–600 kL, which could then be transported safely to Arrow’s facility.

  • BENEFICIAL ONSITE REUSE

    Recovered permeate—approximately 2.5 million litres—was amended and used onsite for:

    • Dust suppression
    • Irrigation of rehabilitated areas
    • Soil conditioning during dam reconstruction
  • FULLY SELF-SUFFICIENT OPERATIONS

    All equipment, offices and plant were powered by a 125 kVA generator.

    Off-road diesel allowed continuous, reliable operation in the remote setting.

Implementation

Design & Preparation

  • BeneTerra worked with Osmoflo to engineer Australia’s first UF/RO system deployed directly on trailer decks for high-recovery seawater-strength feed.
  • System was designed for “plug and play” setup to minimise site disturbance.

Site Establishment & Commissioning

  • A fully bunded 800 m² site was established in 2 days.
  • Installation (plant, tanks, power, pipework, pumps) took an additional 2 days
  • Commissioning and optimisation took 3 days.

Operations

  • UF/RO treatment ran for 5 weeks, including commissioning, processing the majority of the 5 ML volume.
  • The BeneVap BV300 operated for a further 2 weeks to process brine and concentrate streams.

Demobilisation & Rehabilitation

  • Demobilisation occurred progressively as rehabilitation works advanced.
  • The UF/RO unit was fully removed within 2 days, allowing final earthworks, shaping, seeding and site finishing to be completed before the wet season.

Results & Impact

Water Treatment Outcomes

  • ~5 million litres processed
  • 3 million litres of permeate recovered for beneficial reuse
  • 1.4 million litres vaporised onsite through BeneVap
  • Only 600,000 litres required offsite disposal

Transport, Safety & Environmental Benefits

  • 45,000 km of heavy-vehicle travel eliminated
  • Major reduction in dust, noise and road-use impact
  • Reduced health and safety exposure for Arrow’s transport operations
  • Full rehabilitation completed ahead of schedule and prior to wet season

Financial Outcomes

  • Project delivered on budget, including a 15% reduction in transport costs alone
  • Efficiency gains from onsite treatment reduced overall program expenditure

Arrow achieved its objectives of safe decommissioning, environmental compliance and reduced operational risk—supported by BeneTerra’s integrated technical, engineering and field capability