GROUNDWATER FLOW PATTERN AROUND GONOHARJO HOT SPRING, KENDAL REGENCY, CENTRAL JAVA

Abstract

The Ungaran Mountain is a stratovolcano-type volcano with a geothermal system. On the northern side of Mount Ungaran, there are hot springs located in the Gonoharjo area, Kendal Regency, Central Java, Indonesia. These hot springs appear on the mountain slopes and are very close to the surface water. This research aims in analyzing the pattern of groundwater flow with surface water flow around the springs and identifying the relationship that occurs between the springs and the nearest river flow. Analysis of the groundwater flow pattern can be determined based on groundwater level contour maps and groundwater flow maps. Such mapping can occur by plotting groundwater level data measured from 16 springs scattered on the slopes of Mount Ungaran. As a result of the measurements taken, the groundwater level ranged from 298.02 m above sea level to 818.47 m above sea level. The highest groundwater level is in the Pakis area while the lowest groundwater level is in the Boja area. The groundwater flow pattern at the study site flows from the top of the mountain and spreads to the north, northwest, west, southwest. Based on the 15 cross sections conducted, it can be identified that in general the relationship between groundwater and rivers flow in the study area is that most of the groundwater supplies surface water.