UPDATE at 5:19 a.m.:
The Marathon Petroleum Company off Starkey Road should be up and running again right now.
Workers had to shut down the plant around 2 p.m. yesterday after there was a spark in a high octane gas tank.
Police and firefighters evacuated homes and businesses within a half mile of the plant in case there was an explosion.
It didn't get any more serious.
Workers fixed a device that measures how much oil or gas is inside tanks, and that solved the problem.
By 9:50 p.m. Monday night, firefighters were able to leave the scene, and everyone was allowed to go back home.
9:50 p.m. update from WDBJ7's Nadine Maeser:
Marathon crews have eliminated any electric hazard by grounding and bounding the high octane tank.
Crews will now be able to fix the electrical malfunction without having local fire crews on standby for possible fire or explosion.
Railways will begin service shortly. Fire crews are leaving the scene now.
Roanoke County Fire and EMS have been on scene for more than 7 hours after there was a spark in one of the high octane tanks.
Marathon crews are still working to fix an equipment malfunction so the facility can re-open in the morning.
Local emergency crews were dispatched to the area off of Starkey Road around 1:45 pm after the spark shut down the Marathon Petroleum Corp.'s facility.
"When that happened they immediately shut down all operations, all electrical service and called us," said Roanoke County Fire Chief Rick Burch.
Blue and red flashing lights lined Starkey Road as fire fighters started to evacuate surrounding homes and businesses within a half a mile radius of the tanks, but some people considered leaving on their own terms.
"I mean with us being such close proximity and them saying its a situation that needed to be monitored I was surprised that no one had even come up to us to say this is a situation you need to be aware of," said nearby resident Kristie Franklin.
According to emergency officials, every tank has a device that measures the quantity of product inside of it and prevents vapors from entering the atmosphere but that device malfunctioned.
"What that has created is a vapor area between the product and the bottom of that dome and that is where the potential problem is with that vapor area," said Burch.
Burch says any kind of spark near the tank could be dangerous given the layout of the facility.
"There's massive building size tanks of oil or gasoline then you veer to the left and there's an abandoned building and railroad tracks and stuff, but the majority of it is tanks and an area where trucks will come and fill up," said Franklin.
It could be a few more hours until all is clear.
Until then, residents who haven't had to evacuate will be keeping a close eye on the progress.
The fuel tank is about 40 feet tall and holds 40,000 barrels of fuel when full. At this time, the tank is less than 1% full with about 2100 barrels. Crews will be working to empty the tank so they can inspect it once the vapors settle.
A fire team from the Marathon Oil Company is on scene to support local fire crews. A Haz-Mat team from Roanoke Fire-EMS is also on scene assisting with precautionary protocols.
Emergency crews are on still on scene at the Marathon Petroleum Company on Starkey Road in Roanoke County.
All operations have been shut down after a spark ignited in one of the gas tanks.
Emergency crews have evacuated residents and businesses within a half-mile radius of the gas tanks. All railroad traffic that runs near the company has stopped, and they are monitoring any and all air traffic in the area.
Roanoke County Fire and E-M-S officials say this all has to do with an equipment malfunction inside one of the tanks. Every tank has a device that measures the quantity of the product inside.
This particular tank holds high premium octane. The device is not working properly, so crews can't tell if there are elevated vapors inside of the tank or not. Because of that, there's a greater chance for a fire or explosion if there is another spark.
To fix that, crews will need to take product from another tank and fill up the affected one so they can get to the device. Crews are expected to start this process shortly. This whole process could take anywhere from three to five hours to fix. All fire and EMS crews will stay on scene until it's fixed.
Crews are working to fix an equipment malfunction at a Roanoke County oil storage terminal.
An evacuation of the immediate area has been ordered, according to Roanoke County Fire and Rescue. There are several businesses in the area.