Data source is the 1971 self published book by Richard Glenn Huffman [deceased], "George Muma Genealogy".
The Charleroi, Pennsylvania, Mail, Monday, June 24, 1929:
Sues Vesta Coal Co. For $5,000 On Negligence Charge
Charging carelessness and negligence in employing a minor under the age of 18 years in violation of the act of May 13, 1915, John S. Mumaw and Elizabeth Mumaw, his wife, of Adah, Fayette county, has brought suit against the Vesta Coal company in Washington to recover $5,000 damages for the death of their minor son, George Mumaw, in this company's mines near California.
The statement of claim sets forth that George Mumaw was employed in the mine to operate a moving electric motor, which loaded and unloaded pit cars to and from the various working places, and assembled trips of cars for the purpose of moving the same to the tipples and bins. On January 31, 1929, he cut a coal car from the motor and in attempting to set the brakes was caught between the side of the entry and the pit car, receiving injuries from which he died February 26, 1929. It is alleged that the deceased was under the age of 18 years, and the company is charged with negligence in employing him in alleged violation of the act of 1915.
http://patheoldminer.rootsweb.ancestry.com/wasvesta1.html
Mumaw, George
(Miner Boy, ca.1929, Vesta No. 4 Mine [Richeyville], Washington Co., PA, Age 17.);
(Killed. Fatally injured, caught between the side of a mine car and an entry, in the Vesta No. 4 Mine, Jan., 31, 1929. Died of his injuries, Feb. 26, 1929. [from the "Charleroi Mail," Charleroi, PA, June 24, 1929.]);
(Lived in Palmer, PA.)