Characterization of soil permeability in prambanan temple yard based on development of in situ test

Prambanan Temple is a cultural site which has been declared as world cultural heritage that is required to be conserved. Due to heavy equipment activities during maintenance period after Yogyakarta earthquake in May, 2006, soil in temple yard become dense, and ponding occurred after rainfall. A poodle layer and a drainage system has ever built to avoid such a problem, but the pond still didn't stop appearing after rain. Permeability parameter needs to be characterized to find exact method of solution. This experiment used Constant Discharge method which suitable for permeability test of sandy soil. The procedure were carried out from unsaturated until saturated soil condition. Volumetric water content were being monitored by using soil moisture probe. The results were value of permeability coefficient from unsaturated until saturated condition. The value of permeability coefficient and soil type characterization was mapping based on geographic reference using software Arcview GIS 3.3. Developed instruments were quite efficient and easy to be implemented on determining field soil permeability coefficient of sandy soil. Using constant discharge model, the value of unsaturated soil permeability can be obtained without establishing the matrix suction. The result of soil permeability characterization mapping can be used to determine the alternative solution of the ponding problem.