The Palabuhanratu coal-fired power plant is the primary source of electricity for both Sukabumi Regency and the southern portion of West Java Province. Historically, coal use has had substantial effects on water quality, air pollution effects on surface waterways (particularly "acid rain" and mercury emissions), other airborne toxicants, and the hydrological cycle as a result of global warming.This study examines the impact of the Palabuhanratu coal-fired power station on the pH of river and groundwater. Since the Palabuhanratu coal-fired power station is located in the Cimandiri sub watershed in Sukabumi, this sub watershed is selected as the site to be evaluated. This study finds that the pH of river and groundwater around coal-fired power plants tends to be very low and acidic.