A Montana-based company was awarded a contract to replace up to 32 miles of fencing along the U.S.-Mexico border in Arizona.

Barnard Construction Co., Inc. will receive $172 million for the first phase, about 14 miles in the Border Patrol’s Yuma Sector. The total contract value could be up to $324 million, Customs and Border Protection officials said in a news release. Construction is scheduled to begin in April 2019.

The Arizona projects include five miles of fencing in Lukeville, an area increasingly used by large groups of families turning themselves in to Border Patrol agents; and 27 miles in Yuma. Officials didn’t say precisely where that fencing will be replaced or upgraded.

Yuma is seeing a significant rise in family unit apprehensions, about 14,500 in fiscal year 2018, bringing the total of arrests to about 26,000. Still, Border Patrol apprehensions remain much lower than in 2005, when agents made nearly 140,000 arrests in one year in the Yuma sector.