A Snowy 2.0 contractor has received its third fine for polluting Kosciuszko National Park waterways.

WeBuild, a contractor involved in the Snowy 2.0 hydro-electricity project, faces the fine after the NSW Environment Protection Authority (EPA) accused it of allowing sediment-laden water to infiltrate the pristine Yarrangobilly River, situated just west of the ACT border.

The EPA's allegations against WeBuild stem from an incident where a pump at a construction site for the Snowy 2.0 project was left unattended, resulting in a staggering 9,000 litres of sediment-laden water being discharged into the Yarrangobilly River.

The incident marks the third fine that WeBuild has received from the EPA in the past four months. 

The previous fines were related to the release of a “sediment plume” into the Yarrangobilly River and sediment-laden water from roadworks that reached Nungar Creek.

Steve Orr, the acting executive director of operations at the NSW EPA, says strict regulations are in place to safeguard fragile ecosystems in the region, including highly specialised flora, fauna, and micro-organisms.

Snowy Hydro has directed enquiries to contractor Future Generation Joint Venture (FGJV).

FGJV is the principal contractor for the Snowy 2.0 project, and is a joint venture of WeBuild and two other engineering companies.

WeBuild and FGJV issued a statement saying they were “acutely aware” of their environmental responsibilities.

“At the time of the event, which occurred unintentionally, it was Future Generation Joint Venture that brought the issue to the attention of the Environment Protection Authority to ensure a quick and safe resolution, which we did achieve with their support,” they said.

“We maintained transparency throughout rectification conducting water sampling and confirmed there was no downstream impact beyond natural variability to the Yarrangobilly River as a result of this incident.

“In addition, we have since undertaken reviews of the event to identify the cause and mitigate the risk of any recurrences.”