Environmentalists say a $15,000 fine handed to coal miner Peabody in June for polluting a creek that leads into the Royal National Park is inadequate, and won't protect the waterways as potential habitat for reintroduced platypus.
The penalty from the Environment Protection Authority was given to Peabody after its failure to properly maintain a dam at its Metropolitan colliery at Helensburgh allowed polluted water to run off into the Camp Gully Creek during heavy rains in January.
The creek flows into the Hacking River then into the national park.
Sutherland Shire Environment Centre spokesperson Dr Catherine Reynolds said the area was potential platypus habitat but members had been raising concerns about mine runoff for years.
"The Royal is one of Australia's best loved national parks yet there is coal visible on the banks of the Hacking River," she said.
Kaye Osborn of the Protect Our Water Alliance (POWA) said fines for mining pollution must be higher if they are to provide a genuine disincentive.
Peabody said since the incident it had cleaned out dams and drains to allow stormwater to be better captured.
"From January to the end of July this year, the mine has received almost 2500mm of rain, nearly double the expected annual rainfall in just seven months," a Peabody spokeswoman said.
"We continue to work cooperatively with the Environment Protection Agency to better prepare for future heavy rain events, including the commissioning of a full review of onsite surface water management, the desilting of stormwater dams and civil works to create an additional pathway for excess stormwater to be captured on site."
The EPA said the penalty - the maximum allowed under law - was for failing to maintain stormwater systems.
"The pollution incident occurred on 13 January and resulted after polluted water overflowed from a dam on the site during an intense rainfall event," an EPA spokesman said.
"Any environmental impact is likely to be minor as heavy rainfall was ongoing over this period. The main reason for issuing the fine was the company's failure to maintain their wastewater treatment system."
After no platypus sightings in the Royal since the 1970s, the NSW Government is attempting to reintroduce a viable population.
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