The fifth chapter of the Qingchuan Diary

In the morning, samples were taken as required, and at the request of the water plant, another sample of spring water was taken. The test results showed that the residual chlorine and turbidity indicators improved further compared to the previous day. The microbial indicators such as total bacterial count and total coliform group in the raw water also improved compared to the previous day. According to local people, an upstream village from the sampling point was buried by a landslide during the 5.12 earthquake, with two mountains merging into one. Therefore, it is suspected that the pollution caused by decay may have affected the water quality.

For everyone's safety, Mr. Xu ordered that no one is allowed to bathe in the river, and encouraged everyone to make do with available materials to create simple shower facilities. The effect remains to be seen.

At noon, the water plant purchased polyaluminum chloride coagulant and completed the production of a simple alum-adding equipment. In the afternoon, we carried out coagulation experiments according to plan and obtained experimental data which can serve as a basis for dosing. Due to a power outage at the water plant, the filter pools could not be used, so we need to wait for the power supply to be restored before conducting production-scale verification. If the experiment succeeds and cave water is put into use, the water quality exceeding standards will be improved.