A recent Massachusetts case involving violations of the federal Clean Air Act serves as a reminder of how dependent we all are upon the honesty and diligence of those responsible for monitoring the purity of the water we drink, the quality of the air we breathe, and the wholesomeness of the foods we eat and beverages we drink. We worry a lot about terrorists. Yet we barely ever give a thought to the guys testing samples at our municipal water plant or operating the pollution controls at the power plant a few towns away -- unknown persons, laboring in obscurity, who can seriously hurt us through negligence and malfeasance. The real daily risks we face are more familiar, more ordinary, and closer than we think. On June 9, U.S. District Court Judge Mark G. Mastroianni sentenced Scott Paterson, age 46, of Manchester, CT, to one year of probation for tampering with environmental monitors while working as an instrument and control technician at the Ber...