Pipecon pleaded not guilty to two charges of breaching the Occupational Health and Safety Act at the Ballarat Magistrates' Court on Wednesday.

Magistrate Gregory Robinson found there was sufficient evidence to support the conviction of Pipecon on both charges after the two-day contested committal hearing

The charges relate to Charlie Howkins, 34, and Jack Brownlee, 21, who died in the double workplace fatality in the Winterfield Estate on March 21 last year.

Howkins died at the scene while Brownlee died the next day in hospital.

WATCH LANA CORMIE SPEAK TO MEDIA OUTSIDE COURT

During defence cross-examination on Wednesday, witness David Rogers, a Worksafe Victoria inspector who attended the accident, said safety documentation for workers at the site was not sufficiently specific for the work being done.

Mr Rogers said he criticised Pipecon's Safe Work Method Statement at the site because it did not detail which specific protection method workers should use in the trenches.

Defence barrister Stephen Russell told the court the Safe Work Method Statement in use at the time of the accident said protection measures such as benching, battering and shields should be used for trench work.

READ MORE: PIPECON TO STAND TRIAL OVER TRENCH DEATHS

"Workers had been told shields, not benching or battering, would be used across the whole site," Mr Russell put to Mr Rogers.

Mr Russell asked Mr Rogers and a second witness from Worksafe, Lesley Ferguson, about previous reports from inspections of Pipecon sites since 2008, highlighting the company's history of providing adequate Safe Work Method Statements.

Prosecuting barrister Andrew Palmer QC, acting on behalf of Worksafe, questioned the witnesses about reports they had made at Pipecon work sites that highlighted a lack of safety measures to prevent workers from the risk of falling into a trench.

Mr Howkin's wife Lana Cormie spoke to media outside the court on Wednesday afternoon.

"We started a nightmare journey that we never should have been put into on the 21st of March 2018, and each of these events just continues the nightmare that is now our lives," Ms Cormie said.

"The company has pleaded not guilty. I just hope that justice will be found."

Mr Brownlee's family were also present at court, alongside other supporters.

READ MORE: HOW THE TRENCH TRAGEDY UNITED TWO FAMILIES IN GRIEF

They wore badges that featured photographs of Mr Howkins and Mr Brownlee and the words 'Charlie and Jack, Justice'.

During defence cross-examination on Tuesday, witness Lorne Heppeler, a subcontractor who was working on the same estate for Pipecon to install sewer pits, said he was surprised no shields were in place at the time the accident occurred.

In answering questions whether safe work procedures were always followed, Mr Heppeler said there were times individual assessments were made on each trench.

"I wouldn't say every time working in a trench above 1.5 metres it was done by textbook," he said.

Mr Heppeler, who arrived at the site after the accident, said some of the trenches at the Winterfield site had been open for more than two weeks because of a slow supply of foam to lay down and complete the job at the time the trench was dug.

"We were always behind. There were three or four pits open at a time," he said.

Another witness, Pipecon site foreman and Winterfield Estate development supervisor Shaun Mahar, said there was a sufficient number of barriers, shields and cages at the Winterfield site to ensure appropriate protection of all workers.

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Mr Mahar said all employees at the site had undergone a safety induction and signed a Safe Work Method Statement for trench work.

During defence questioning, Mr Mahar said he had spoken to Mr Howkins the day before the accident occurred about getting a manhole cage ready for Mr Heppeler to complete his work in manhole eight, where the accident occurred, the next day.

"I presumed they would have used the manhole cage," he said.

"You can never assume a trench is secure."

On Tuesday, the court heard the manhole cage was stored at the top of the Winterfield site where he was at the time but the accident occurred around 500 to 700 metres lower on the site.

Mr Mahar said it was a situation where he could have done with 'more people on site' and had put in a request to the office for more staff.

Expert witness geotechnical engineer Dr Chris Haberfield provided evidence that shields available at the Winterfield site would have been sufficient in providing proper protection if used.

Dr Haberfield said he had come to the conclusion both Mr Howkins and Mr Brownlee were in the trench at the time of the collapse.

Another witness testified he had completed around 10 safety checks at the Winterfield site.

During the opening addresses, Mr Parmer said trenching and pipe laying occurred without using appropriate safety measures to protect workers from the risk of engulfment and failing to provide appropriate supervision.

In defence opening remarks, Mr Russell told the court Pipecon disagreed with the allegations trenching work was undertaken without safe measures and supervision in place.

"There was a safe work statement signed," he said.

"Pipecon indicate at all times trenching work was conducted in a safe manner."

Pipecon company director Andrew Mahar was present in the front row at court both days.

Pipecon is charged with two alleged breaches of the Occupational Health and Safety Act:

The charges carry 9000 penalty points each ($161.19 a point), and based on calculations carried out by The Courier, it means the company could be fined almost $3 million if found guilty and given the maximum penalty on both counts.

Pipecon will return to the County Court in Ballarat for a directions hearing on January 30.

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