Published December 10, 2020, 6:02 PM The Department of Environment and Natural Resources (DENR) has formed four composite teams to investigate quarry operations in Rizal province following a massive flooding that submerged some parts of the province and Marikina City during the onslaught of typhoon Ulysses last month. Through its Region 4A office, the DENR will be equipped with aerial mapping drones to investigate the quarry operations specifically within the Marikina River Basin. The composite teams were created in line with a memorandum order issued by the Mines and Geosciences Bureau (MGB) in Region 4A temporarily suspending at least 11 quarry and crushing plant operators within the river basin, which river system drains toward the Marikina River.