There was no evidence the lawyers had been doing anything other than discharge their obligation to assist experts address issues for the NSW Land and Environment Court case, Justice Brian Preston said in a ruling on Friday.

He rejected Grafil attempts to access emails, file notes and draft affidavits between EPA lawyers and several experts, including documents relating to the cost of work for the prosecution case, and said they were subject to legal professional privilege.

Grafil Pty Ltd and Mr MacKenzie’s son Robert entered pleas of not guilty to using Macka’s Sand and Soil at Salt Ash as an unlawful waste dump after they were charged in 2016 following a lengthy environmental crime investigation.

The EPA acted after investigations of alleged dumping from 2013, when stockpiles of waste up to eight metres high, 40 metres wide and 100 metres long were found near and in waterways.

The EPA initiated the Land and Environment Court action after investigations in October, 2015 found an additional 360 tonnes of waste at the Salt Ash site, in breach of orders made in 2013, with 10 tonnes found to contain asbestos.

The EPA initiated the Land and Environment Court action on May 1, 2016, a day before announcing it had fined Grafil and Macka’s Sand $15,000 for land pollution by asbestos waste.

A full Land and Environment Court hearing is set down for February.

In a hearing after Grafil applied to the court for the documents, the EPA agreed to waive legal privilege over a draft technical investigation report with the file name “Project Trojan Salt Ash Report”.

Grafil sought emails between the EPA and an expert whose report discusses the environmental consequences of materials alleged by the prosecutor to be waste.