BEIJING, May 23 (Reuters) – The graft watchdog of China’s ruling Communist party said on Wednesday that officials from a branch of Aluminum Corp of China, known as Chinalco, and a number Chinese cities had been disciplined for environmental failures. The general manager of Chinalco’s Lanzhou branch, in the northwestern Gansu province, was publicly criticised for its “unsatisfactory” and “untimely” handling of hazardous solid waste that was stacked in breach of rules, the Central Commission for Discipline Inspection (CCDI) said in a statement. China has made a clampdown on solid waste a key pillar of its environmental protection campaign. Two deputy general managers at the Lanzhou branch were each given a warning, while the manager of the health, safety and environment department was dismissed, the statement added. Chinalco, China’s biggest state-run aluminium producer, did not immediately respond to a request for comment. Several Lanzhou city officials were interviewed or cautioned about the same case, according to the CCDI. Other places where officials have recently been held accountable for failure to properly implement environmental protection laws were named as Lianyungang, in China’s eastern Jiangsu province, Tongling in Anhui province, Ninjin county in Hebei province and the municipalities of Tianjin and Chongqing. Separately, China’s Ministry of Ecology and Environment said on Wednesday that the number of environmental investigations and recorded infringements in the country had risen from 97,000 in 2015 to 233,000 last year, with the penalties handed out reaching 11.58 billion yuan ($1.81 billion) in 2017.