From May 1978 through February 1979, 334 samples of rain were collected on a twice-weekly basis in the summit area of Kilauea Volcano, Hawaii. Throughout the period the volcano was in a noneruptive state. The samples were analyzed for pH and conductivity as well as for the concentration of the anions F-, Cl, NO2, PO4-3, Br-, NO3-, and SO4 = . At a distance of 0.8 km downwind of the degassing center rainwater pH was observed to be as low as 3.0 and to have a median pH of 3.6. The maximum observed concentration of SO4 = was 36 mg/l. The median pH 11 km downwind was 4.2, which approached the pH measured in precipitation on the island uninfluenced by the volcanic emissions. |