During heavy rain on March 24, oily water was discharged from the refinery into Botany Bay. The facility holds an environment protection licence issued by the EPA and the licence includes strict conditions.

Caltex estimated that between 200 and 400 litres of oily material mixed with more than 3 million litres of clean cooling water and an undefined quantity of stormwater were discharged into the Bay.

The oily water spread to the coastline around Bare Island and Congwong Bay. During the rain event wastewater was also discharged from the submerged ocean outfall at Yena Gap in breach of licence limits.

Following the incident, the EPA directed Caltex to undertake an ecological assessment of the effects of the oily discharge at Congwong and Little Congwong Beaches.

The assessment found that while there may have been an initial impact, the incident did not result in long term significant environmental damage.

The company has also put preventative measures in place to ensure a similar incident does not happen in the future following heavy rain.

The refinery ceased to operate in October 2014 and now operates as a fuel terminal. It remains licensed by the EPA.

Under the terms of the Enforceable Undertaking, Caltex will contribute:

• $5000 to National Parks and Wildlife Service for the discovery program – marine environment teachwild activity at La Perouse in which school students are given guided tours by rangers and scientists from CSIRO;
• $35,000 to the NPWS catchment and beach/dune rehabilitation and habitat restoration project – Congwong Precinct which includes works to prevent erosion and restore habitat in the Congwong Precinct;
• $50,000 to Sutherland Shire Council for the Marton Park wetland rehabilitation project which includes works to rehabilitate the Wetland; and
• $30,000 to Randwick Council for the discover your coast program (marine and coastal adventure program) which includes a range of free and affordable activities aimed at helping families and children of all ages discover unique marine and coastal environments.

"Enforceable Undertakings were just one of a number of tools the EPA can use to achieve environmental compliance from industry. Others include formal warnings, penalty notices, notices and directions, mandatory audits and, when necessary, prosecutions,” EPA director, metro branch Giselle Howard said.

"Enforceable Undertakings are often imposed when there is a serious breach of licence requirements to ensure measures are promptly put in place to redress any environmental harm and obtain a good and lasting benefit for the environment.”