The building company operating in Raymond Terrace was ordered by the Raymond Terrace Local Court to pay the amount after being found guilty of eight offences.

Following a two-year investigation by the Port Stephens Council's rangers, the building company was found guilty of pollution offences and failure to comply with development conditions and ordered to pay fines and costs totaling nearly $30,000.

"The offences took place over a two-year period while the company constructed a series of residential dwellings in Raymond Terrace. Two of the charges related to pollution of waters and six were for failure to comply with conditions of development consent," a council spokesperson said.

After submissions from Port Stephens Council rangers and a number of appearances in Raymond Terrace Court, a plea deal was accepted by both parties and the matters were listed for sentencing.

The council's environmental health and compliance coordinator Marc Goodall described the case as a good outcome for the Port Stephens community.

"Council places a high priority on protecting the environment and responding to pollution events," Mr Goodall said.

"This conviction by the local court is a great win for the council and the community, and supports our approach to ensuring builders comply with the law. It is [also] a timely reminder to all builders in Port Stephens to act responsibly and protect the environment or face the consequences.

"If builders are not sure about their responsibilities under the environmental legislation, they can contact us here at council," he added.

The building company has taken action to clean up the sites and remedy the pollution events.