The council is sticking to its steadfast belief that the traffic plan was not adopted, claiming yesterday the department made errors, misunderstood the nature of the plan, and did not properly investigate the situation.

The document became the catalyst for early works at the mine grinding to a halt earlier this month, when a contractor was killed by an oversized truck carrying equipment to the mine.

The council rescinded its support for the mine to begin construction work after the accident, claiming at the same time it had never approved the traffic management plan that was necessary under the conditions of the mine's approval.

Xstrata Coal claimed it did have approval, and the Department of Planning has backed that view.

In a letter sent to the council on Monday, the department's major project approval executive director Chris Wilson said the department had spoken with Xstrata Coal and was satisfied the company complied with the relevant conditions.

"It is the department's view that council has approved the construction management plan," Mr Wilson wrote.

The council issued a statement yesterday.

"The correspondence from the Department of Planning is not a legal opinion and is founded upon an error of fact," the statement said.

The statement said the council believed the department had confused two different traffic plans.

"In coming to its view, the department, somewhat curiously, spoke with the mining company concerned but . . . not the council or to examine the evidence held by the council in relation to the matter."

A Department of Planning spokesman said it stood by its opinion.