CRUCIAL sediment testing in Gladstone Harbour demanded by the Environment Department was not completed before the Federal Government approved the controversial Western Basin dredging project in 2010.
The sediment tests were requested after regulators found initial 1000-borehole testing provided by Gladstone Ports Corporation was lacking in several areas.
The revelation comes just days after the Federal Government approved Arrow Energy's LNG project, and follows news that the State Government is investigating a private lease of the port.
A key area of the Environment Department's request for additional testing was near the RG Tanna Coal Terminal - where molluscs were experiencing the rising effects of a highly toxic chemical (TBT) in 2009. The GPC did not give that information to authorities at the time.
Documents obtained under Freedom of Information revealed the port filed an "exemption from further sediment testing" in July 2010.
Regulators found the initial testing regime was incomplete the next month.
But despite the concerns, and without the data requested, the Federal Government still approved the largest-ever dredging project in the Great Barrier Reef World Heritage Area, in October that year.
Additional results were not provided until April 4, 2011. They were not released.
But a GPC spokeswoman said the results were within national dredging guidelines, and that no contaminants exceeded the guidelines, with the exception of locally occurring metals.
She said GPC applied for the exemption as the port "believed that sufficient evidence existed to evaluate the footprint".
But APN Newsdesk has obtained correspondence that shows regulators knocked back the exemption application, over concerns that the distribution of tests were "uneven and not representative of the whole dredge phase area".
Despite the omission of the study on TBT from the EIS potentially breaching federal environment laws, the department said it did "not consider an investigation into this matter is warranted".
A port spokeswoman said the GPC applied for an exemption, "which was not granted by the Federal Government".
"GPC then undertook the additional sampling required to meet the National Assessment Guidelines for Dredging, the regulatory guidelines mandated by the Federal Government," she said.