A married couple has been sentenced to prison for fireworks violations at a St. Louis area factory where explosions have taken two workers’ lives. Prosecutors agree the crimes did not cause the deadly explosions at Pyro Products in Jefferson County. Still, a US District judge found 41-year-old Ronald Walker and 39-year-old Kim Walker guilty of mishandling explosives at the plant. They will spend a little more than a year in prison and will have to pay a $3,000 fine. Ronald Walker is the former president of Pyro; his wife, the former chief financial officer.The Pyro plant in Dittmer came under scrutiny after the fatal explosions in 1999 and 2000.