Scenario: Your client is Elara Windfarms Pty Ltd. Elara is proposing to establish a wind farm on the Central Coast, Hunter Valley Region of NSW. To take advantage of maximum wind flow the company is proposing a site on a coastal cliff face adjacent to the ocean.

The Planning Minister holds a press conference praising the project as "helping the inevitable transition towards more renewable sources of energy and jobs for Hunter Valley workers". The local conservation group, Friends of Myall, responds by asserting that the proposed site, which was badly affected by the 2019 bushfires, is also adjacent to the Hunter Valley Weeping Myall (Acacia pendula) Woodland; and the Red-tailed Black-Cockatoo (Calyptorhynchus banksii banksia) was known to haunt the area before the bushfires. One month later the Minister announces that the project, which has an estimated capital cost of $25 million, will be designated 'State Significant Development'.

Buoyed by this announcement, Elara employs contractors to begin preliminary excavation work, sending plumes of silt into an adjacent watercourse that leads to the Myall Woodland and impacting on the ability of downstream landowners to access clean water.

Question:

Does Elara Pty Ltd any legal liability for the pollution caused by their contractor.

the answer should encompass both NSW State and Federal law (where relevant); and cite relevant legislation and case-law.