STUDI SEBARAN AIR LINDI DI SEKITAR TEMPAT PEMBUANGAN SAMPAH TERPADU (TPST) PIYUNGAN KABUPATEN BANTUL DENGAN PENENTUAN ISOTOP STABIL (2H,18O) DAN KIMIA AIR

ERWIN ANDRIAWAN PUTRA GONTI, Dr. Ir. Agus Budhie Wijatna, M.Si. ; Drs. Satrio, M.T.

2016 | Skripsi | S1 TEKNIK NUKLIR

Tempat Pembuangan Sampah Terpadu (TPST) Piyungan adalah TPA berbasis sanitary-landfill yang menjadi lokasi buangan sampah dari tiga daerah yaitu Kota Yogyakarta, Kabupaten Sleman dan Kabupaten Bantul. Besarnya volume sampah dan curah hujan yang tinggi di sekitar TPST Piyungan berpotensi menghasilkan air lindi dalam jumlah besar dan merembes ke dalam tanah, serta mencemari airtanah. Tujuan utama dari penelitian ini adalah menentukan pola sebaran air lindi di sekitar TPST Piyungan yang ditinjau dari kesamaan genesis airtanah dan kualitas airtanah. Pada penelitian ini, komposisi isotop deuterium dan oksigen-18 air sumur milik warga diuji menggunakan alat LGR DLT-100 untuk menentukan kesamaan genesis airtanah. Analisis kimia air dilakukan pada setiap sampel untuk menentukan kualitas airtanah dengan menguji kadar kation-anion yang meliputi Na+ (natrium), K+ (kalium), Ca2+ (kalsium), Mg2+ (magnesium), SO4-2 (sulfat), Cl- (klorida), dan HCO3- (bikarbonat), serta menggunakan metode diagram piper untuk menginterpretasikannya. Hasil analisis komposisi isotop berdasarkan kedekatan nilai 'delta' dan uji ANOVA satu arah menunjukkan bahwa sampel-sampel dalam Kelompok I (S2, S3, S4, S5, S8, S10, S12, S20) mempunyai genesis airtanah yang sama dengan rentang nilai -38,51permil sampai dengan -33,41permil untuk delta2H dan -6,81permil sampai dengan -5,22permil untuk delta18O. Berdasarkan interpretasi diagram piper, hampir semua sampel air mempunyai karakteristik dominan ion Ca2+-Mg2+-HCO3- yang merupakan tipe air sadah sementara dan ciri-ciri air tawar berasal dari airtanah dangkal. Kadar parameter kimia seluruh sampel airtanah sudah sesuai dengan ketentuan kualitas air dalam Permenkes No.416/MENKES/PER/IX/1990.

Piyungan Landfill is a sanitary-landfill which is used as the waste disposal site from three regions namely Yogyakarta City, Sleman District, and Bantul District. The large waste volume and high intensity of rainfall around Piyungan Landfill potentially result leachate in large quantities and seep into the soil, as well as contaminate groundwater. The main objective of this study was to determine the distribution pattern of the leachate around Piyungan Landfill by analysing the similarity of groundwater genesis and quality of groundwater. In this research, the isotopic composition of deuterium and oxygen-18 from every well water owned by residents were tested using a LGR DLT-100 to determine the similarity of groundwater genesis. Water chemistry analysis was carried out on each sample to determine quality of groundwater by testing the cation-anion levels included Na+ (sodium), K+ (potassium), Ca2+ (calcium), Mg2+ (magnesium), SO4-2 (sulfate), Cl- (chloride), and HCO3- (bicarbonate), as well as using piper diagram to interpret it. Results of the isotopic composition analysis of groundwater based on the value proximity of 'delta' and one-way ANOVA test showed that the samples in Group I (S2, S3, S4, S5, S8, S10, S12, S20) had the same groundwater genesis with a range of values of -38.51permil to -33.41permil for delta2H and -6.81permil to -5.22permil for delta18O. Based on the interpretation of the piper diagram, almost all water samples had dominant cation-anion characteristics of Ca2+-Mg2+-HCO3- which were type of temporary hard water and characteristics of freshwater from shallow groundwater. Levels of chemical parameters entire groundwater samples were in accordance with the regulation of health minister No.416/MENKES/PER/IX/1990 for water quality.

Kata Kunci : TPST Piyungan, deuterium, oksigen-18, diagram piper