The potential closure of a Mon Valley frozen food processing plant will create a “territorial disaster” for the 252 workers – many of them immigrants – who are employed there, according to a Pittsburgh immigration attorney. Facing a lawsuit for allegedly defaulting on $90 million in loans, Fourth Street Barbecue is downsizing at its two Charleroi area plants that operate under the Fourth Street Foods name by the end of the month, according to a Worker Adjustment and Retraining Notification Act notice filed with the state. Closure of the plants is possible, according to the notice. Immigration attorney Joe Murphy...