O’FALLON, Mo. – Digging will soon resume in O’Fallon, Missouri, where residents recently evacuated because of a gas line strike.

The contractor whose excavator hit a gas line said the line was unmarked where they were digging.

“This is the perfect example of what happens when utility lines are mismarked,” said Derek Leffert of Gateway Fiber. “That has occurred at least 321 times in here the city of O’Fallon since January.”

Leffert said Gateway Fiber was surprised its subcontractor hit a gas line on Nov. 7 on Sunshine Drive because there was no sign, they were even close to a line.

“The cause of the damage is the utility. The gas company mismarked the line, plain and simple,” Leffert said. “It’s black and white here. They mismarked the line by at least nine feet.”

Many of the markings are seen in Gateway’s request to Missouri 811 to have underground utilities located. Leffert pointed out that the clearest gas line markings are flags on the opposite side of the road.

“When it crosses right here, that’s where we see it nine feet away from where the actual hit took place,” Leffert said as he walked along a solid yellow line in the road.

“We take all of this very, very seriously. It’s a big part of my job,” said Craig Hoeferlin, vice president of operation services and safety management systems for Spire.

“In our case, we have a contractor locate for us,” he said.

Hoeferlin showed FOX 2 where Spire believes their locate contractor began identifying the gas line with faint spray-painted dots in the grass but never finished.

“Those dots were put down, and for whatever reason, the locate contractor didn’t put down the final marks,” he said.

Spire contracts with a company called USIC to do the locates. USIC has not answered multiple emails, and phone calls to FOX 2 have been made since Nov. 7.

Hoeferlin said that he hopes excavators will call anytime they see anything strange, like what happened on Sunshine Drive.

“There were preliminary marks there that indicated that a gas main,” he said. “So, if the excavators aren’t sure, give us a call, we’ll come back out because that’s part of the partnership.”

Leffert maintains there were no visible markings and that they had photos before they started digging to prove it.

A new O’Fallon ordinance suspended digging while a safety monitor got to the bottom of what happened. The work has now been approved to continue.

For some context on how often this happens, we ran numbers statewide and found that just this year, Missouri 811, which oversees safe digging, documented nearly 20,000 cases of incorrect utility locates.