Nashville stores hundreds of tons of deadly chemicals downtown that could become toxic targets. NewsChannel 5 investigates.more>>
(Story created: 11/15/06)
A NewsChannel 5 investigation revealed potential terrorist targets that could put residents' safety at risk -- tanker cars filled with deadly chlorine gas at Nashville's water plant.
The investigation discovered that not every city runs the same risk.
Several cities have switched to a safer alternative. McMinnville is one of those cities.
Six years ago McMinnville did some tests. The results showed dozens of workers and thousands of residents could die in a catastrophic accident, so they stopped using chlorine gas to treat their water.
The McMinnville Water Department uses a chemical that is a 15 percent solution of liquid bleach.
It is stored in 2,500 gallon tanks and pumped into the city's water supply. The liquid bleach works like the chlorine gas used by Nashville and other cities.
It disinfects drinking water before it gets to homes and wastewater before it is dumped back into the river.
The only difference is that liquid bleach is much safer than chlorine gas.
"The gas is very dangerous. Of course it hovers low to the ground and large areas such as McMinnville, we'd have to evacuate a large portion of that," said Paul Williamson with the McMinnville Water Department.
McMinnville made the switch to liquid bleach six years ago after the city saw the study.
Wastewater Treatment Plant Manager Tony Myers said the study showed the dangers of using chlorine gas.
"If an individual breathes it into his lungs, his lungs fill up, produce fluid, and he drowns on his own fluid. With the bleach, we would get minor burns on our skin," Myers said.
Myers said a worst case scenario involving chlorine gas would force the evacuation of at least five thousand people.
"We used a scenario that if we were unloading a ton cylinder off a truck and it fell off the truck and hit the ground and busted and released all the gas at one time, then the impact point was 1.3 miles around the plant," Myers said.
He said the choice was obvious to city leaders, switch to liquid bleach. In McMinnville, the cost to convert to liquid bleach was $28,000.
The liquid bleach is more expensive than the chlorine gas. McMinnville pays $3,000 more per year for the bleach.
One city official said the cost is worth it even if it saves just one life.
At least five other Tennessee cities use liquid bleach instead of chlorine gas to disinfect water. They are Gatlinburg, Pigeon Forge, Kingsport, Harriman and Bristol.