football fields away from the tank itself, still smoking and occasional flames. >> it's been going on since you got here. >> just trying to get enough foam and water on there to go ahead and try and knock it out. >> the smoking cauldron ominously flares up. >> what causes the flash we keep seeing? >> right now, it could be several things. as i was videotaping the tank fire, there were a few flare-ups and you could see the flame billow out but just as soon as it flared up, they put water on it and it would go back down. >> officials believe the fire is close to being extinguished. >> i assume that whatever oil was in there was just burning itself out. and all the firemen became, you know, relaxed. some pulled out sandwiches. went and got myself and drink and was ready to pack and leave. >> but a dangerous condition known as a boilover is brewing. >> couple of fire departments looked at the footage and, you know, was apparently one of the first times a boilover type