Updated: 9:33 AM EST January 12, 2021 LANCASTER COUNTY, Pa. — The emergency warning system at the Muddy Run Pumped Storage Facility in Lancaster County will be tested Thursday morning, Exelon Generation Company announced Tuesday. The test is scheduled to be held at 10 a.m., Exelon said. During the test, a brief tone will sound, followed by the words “this is a test, this is a test.” The test will last approximately two minutes, according to the company. No action by the public or any county or local emergency organization is necessary during the test, Exelon said. The system, designed to warn the owners and residents of cottages along a stretch of Conowingo Pond in the event of an emergency at Muddy Run, consists of six sets of loudspeakers mounted atop poles upstream and downstream of the facility.