Potentially dangerous chemical goes up in smoke

Potentially dangerous chemical goes up in smoke

By: Chris Menees Messenger Staff Reporter

By CHRIS MENEES Messenger Staff Reporter Several hours of careful planning and preparation by police all went up in smoke Tuesday. But that’s just what they wanted. A loud boom and a puff of smoke shortly before noon Tuesday in a vacant area across from the Obion County Fairgrounds signaled the detonation of a potentially volatile container of an old chemical recently discovered in Union City High School’s chemistry lab. Union City Police Department investigator Chris Cummings said the old container of picric acid was discovered when chemistry teacher Mandy Hopper was cleaning out the lab. She contacted Tennessee Department of Environment and Conservation environ-mental specialist Ken Nafe, who asked her to send him a photo of the picric acid. After seeing it, he instructed the teacher to stay away from the chemical and contact a bomb squad for its safe removal and disposal. Nafe told The Messenger Tuesday that the Department of Environment and Conservation offers a program that aids in the cleaning of old chemicals from school labs, allowing environmental specialists to work in conjunction with teachers and local authorities. Cummings explained that the picric acid, which needs to stay wet, had completely dehydrated and become crystallized. He said it had been in the lab for many years and said it is not uncommon to find the chemical in labs. “It used to be a very common thing in schools and it had uses in labs,” he said. The Union City Police Department was contacted about the discovery of the chemical and in turn contacted the Jackson Police Department Bomb Squad, with whom Union City police have done some training in the past. Cummings also went online and began to research picric acid. According to the online encyclopedia Wikipedia, picric acid is a chemical compound more formally called 2,4,6-trinitrophenol (TNP) and the yellow crystalline solid is one of the most acidic phenols. Like other highly-nitrated compounds such as TNT, picric acid is an explosive. Modern safety precautions recommend storing picric acid wet. When it is dry, it is relatively sensitive to shock and friction, so laboratories that routinely use it store it in glass or plastic bottles under a layer of water, rendering it safe. Cummings said members of the bomb squad advised local police that as long as the container of chemical was sitting in the lab where it had been sitting for decades and school was dismissed for the summer, the chemical posed no more threat today than it did the previous day. They explained that it would not spontaneously explode. Plans were made for the bomb squad to arrive in Union City on Tuesday morning, setting in motion a series of preparation work that began about 9 a.m. Once the two officers from the bomb squad arrived and reviewed the situation, police summoned the Union City Fire Department and an ambulance crew to be at the scene on standby, which is standard procedure. Because an ambulance from Regional Emergency Medical Services was unavailable, the nearby Twin Cities Ambulance Service responded by mutual aid. The school was also evacuated as a precaution, with faculty removed from the main school building and band students from the nearby band building. All of those involved in the chemical’s removal gathered inside the chemistry lab for a final briefing before the actual removal in order to make sure everyone was well informed. The removal of the picric acid ultimately took place about 2 1/2 hours after police initially arrived on the scene. “You take your time, plan it out,” Cummings said. One of the officers from the bomb squad donned a specially-designed bomb suit and physically placed the container of the chemical into a special detonation bag. Cummings said even though the bomb squad’s robot device is the safest removal method, the bomb squad members opted not to use it in this particular case because the picric acid was so “shock sensitive” and the robot tends to knock things over since it operates with the use of a camera for guidance. “The only way to move it was to actually send a person to do it,” Cummings said. “With the detonation bag and the small amount of the chemical, we felt it was the best option.” The bomb squad officer carefully walked the detonation bag outside the lab using an exterior door on the west side of the school building. It was then gently placed into a hole that had been dug in a half-load of sand in the back of a dump truck provided by Union City Public Works. Cummings drove the dump truck to the designated vacant area on the north side of East View Cemetery, across from the fairgrounds in Union City, for the detonation of the chemical by the bomb squad. He said he was really very well protected in the cab of the truck since the chemical’s being placed in the hole would have sent the blast upward in the event it prematurely detonated and because of the truck’s steel dump bed. “I never had a worry. But I didn’t want to hurry,” he said. The streets around the high school and Miles Avenue were blocked shortly before noon as the dump truck and the procession of emergency vehicles traveled to the designated area of the cemetery for the detonation. The bomb squad member carefully walked the detonation bag to the area and the small charge for its detonation was set. Within seconds, a very loud boom and a cloud of smoke marked the detonation of the picric acid. Afterward, the bomb squad members returned to the detonation area to ensure all of the explosive had detonated and the area was completely safe. “It went off without a hitch,” Cummings said. Published in The Messenger 6.4.08

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