China's environment watchdog on Wednesday urged local authorities in Hebei and Tianjin to clean up sewage pits after media reports revealed massive pollution.
Pictures of the contaminated pools went viral on Tuesday after a report from an environment organization disclosed the pollution.
The Ministry of Environmental Protection (MEP) said it has sent two investigations teams to look at the sewage pits and ordered local authorities to intensify monitoring of water and soil in and around the polluted pools.
According to Dacheng County in Hebei Province, where two reportedly polluted pools -- 170,000 square meters and 30,000 square meters -- were formed by years of digging, illegal dumping of waste acid in 2013 contaminated water and soil in the areas.
Dacheng authorities have started to treat the pollution but have not yet finished the work, according to the MEP statement.
Two treatment firms were contracted to bring water quality back to normal, but they both failed, according to the county government of Dacheng.
Dacheng has set aside 38 million yuan (5.59 million U.S. dollars) to treat the pits in 2017.
The investigation team demanded the Dacheng government speed up the clean-up.