See page 104 of the report.
"The key performance indicator “Process waste water” is measured after waste water treatment in BMWGroup plants (incl. the BMW Brilliance Automotive Ltd. joint venture in Shenyang/CN) has taken place. Together with the waste water from sanitary facilities at the plants, this is the figure for total waste water. Due to factors such as evaporation, water input does not correspond to total waste water"