Geology
Regionally, the predominant geological feature is the Sydney Basin, formed via igneous rifting and crustal thinning resulting in the deposition of Permian and Triassic aged sedimentary sequences. Within the UWJV Project area Permian sediments form the Wittingham Coal Measures of the Hunter Coalfields. The coal measures generally plunge in a west to south-westerly direction and outcrop to the east of the Project area near the Hunter River.

The Wittingham Coal Measures comprise the economic coal seams interspersed with overburden and interburden consisting of sandstone, siltstone, tuffaceous mudstone and conglomerate. Quaternary alluvial deposits unconformably top the Permian sediments. These deposits consist of silt, sand and gravel in the alluvial floodplain of the Wollombi Brook. To the east of the Wollombi Brook is a sequence of aeolian sands, known as the Warkworth Sands Formation, that form a thin capping on the underlying Permian bedrock Additionally, the Triassic Narrabeen Group also unconformably overlie the Permian sediments. The Narrabeen Group, which formed from uplift during the Triassic, comprises fluviatile deposits that form the ridges and a high plateau within the Wollemi National Park, west of the Project Area. Surficial weathering, typically present as a thin heterogeneous layer of unconsolidated material overlying fresh bedrock occurs across the project area.

Locally, the predominant stratigraphic units that occur with ........

Mining and coal handling at United Wambo involves conventional open-cut mining methods involving truck and excavator/shovel operations.

United Wambo comprises of mining within two open cut pits - a new open cut coal mine at United, known as the United Open Cut, and the existing open cut operations at Wambo, known as the Wambo Open Cut. Operations at United Wambo occurred in three Phases during 2020 as defined by SSD 7142; Phase 1A, Phase 1B and Phase 2. The new combined open-cut mine is forecast to produce 10 million tonnes of thermal and metallurgical coal annually.

Phase 1A
Phase 1A commenced on the 6th January 2020 involving construction works and development of the United Starter Pit. Extraction of material from the United Starter Pit commenced under Phase 1A in May 2020.

Phase 1A, included the following activities:
• Salvage of Aboriginal artefacts;
• Clearing of vegetation to facilitate construction and mining activities;
• Construction and use of the Construction Infrastructure Areas (CIA);
• Upgrades to the Mine Infrastructure Area (MIA) at Wambo including the construction of a new workshop, fuel farm, administration offices, carpark;
• Construction of water management infrastructure including three mine water dams (U1, U2 and U3), the Northern Clean Water Drain and water pipelines;
• Installation of erosion and sediment controls;
• Construction of the realigned 330kV, 66kV and 11kV power lines;< ........

United Wambo Joint Venture (UWJV) open-cut mine commenced operation in January 2020. The mine integrates existing open-cut operations at the Wambo coal mine with a new open-cut mine at the adjacent United coal mine.

Operations at United Wambo occurred in three Phases during 2020; Phase 1A, Phase 1B and Phase 2.

During Phase 1A and 1B, no coal produced from the United Open Cut was processed by the Wambo CHPP.

During Phase 2, ROM coal mined in the United and Wambo Open Cuts is hauled to the ROM pad located near the Wambo CHPP. Coal hauled to the ROM pad can be placed directly into the ROM bin or placed onto the main ROM coal stockpile. ROM coal is crushed and washed at the Wambo CHPP and a product coal stockpile is used to stockpile product coal, prior to reclaim and loading to trains for transport off site.

The run-of-the-mine (ROM) coal will be transported to the existing coal handling and preparation plant (CHPP) at the site. The existing co ........