Yarriambiack Shire Council's infrastructure and planning director James Magee said the company ran a freight trial in November and built the barrier in December.

"The barrier was part of a permit condition enforced by the State Government that Iluka needed to stay within noise limits," Mr Magee said.

"Iluka ran a freight trial for about two weeks in November and on January 23 started sending mineral sand from Hopetoun on three trains a week.

"That will gradually build up to 13 trains a fortnight."

Mr Magee said the November trial tested noise levels and the sound barrier was then designed to meet Hopetoun's needs.

"It's definitely better for Hopetoun having trains instead of B-doubles through the town," he said.

"The aim is to keep as many trucks off the Henty Highway and out of Hopetoun as possible.

"Now, the trucks will only come south from Ouyen as far as Hopetoun and no longer go through the Hopetoun business district at all.

"They bypass the town through Campbell Street, which has been upgraded by council and funded by Iluka to cope with the added traffic."

Iluka Resources Murray Basin commercial manager Ronnie Calvert said the company would run three or four trains from Hopetoun until May or June.

"The plan is to load trains at Hopetoun between 6pm and 10pm and run each train down to Hamilton overnight," Mr Calvert said.

"Then they will be unloaded at Hamilton between 5am and 9am and return to Hopetoun."

Mr Calvert said a train was sent to Hamilton overnight last night and trains would also travel to Hamilton tonight, tomorrow and Wednesday.

"Each week we previously sent 40 B-double trucks to Hamilton, so with the introduction of trains, there is significantly less traffic through towns including Warracknabeal and Horsham," he said.

Mr Calvert said each train could carry 1500 tonnes, but they would carry 1300 tonnes while the company moved its mine site near Ouyen.

"At the moment we have a production gap while we move sites, so the Hopetoun line hasn't been used a lot lately," he said.

"But we do want people to be aware that the line is being used, that there is a train and to stop at the level crossings, especially because one of the signals is close to a school."