Metode Pengumpulan Data dan Analisis Kualitas Air Oleh Eko Sugiharto Koordinator Penelitian PSLH UGM

Mengapa Perlu ? Lima alasan utama keperluan pemantauan: mengetahui karakter air dan identifikasi kualitas air dari waktu ke waktu; mengidentifikasi problem spesifik air (bila ada); memberikan informasi terjadinya pencemaran mengevaluasi ketaatan terhadap peraturan perundang-undangan mengevaluasi effisiensi pengelolaan air yang telah dilakukan (RKL-RPL , UKL-UPL)

STRATEGI PENENTUAN LOKASI PENGAMBILAN Tergantung pada: Jenis perairan Tujuan Pemantauan Ketelitian yang diinginkan Karakter parameter yang dipantau

JENIS PENGAMBILAN SAMPEL Grab Composite Integrated Continous

IDENTITAS SAMPEL Data Minimal yang diperlukan untuk identitas sampel: Nomor / Kode sampel Tanggal dan Jam Pengambilan Lokasi Cuaca saat pengambilan Suhu air, suhu udara Nama pengambil sampel Bahan yang ditambahkan (bila ada)

IDENTITAS SAMPEL For each visit to an individual station where field and/or samples are collected record the following: Station ID Sampling Date Location Sampling Depth (if other than surface) Sampling Time Sample Collector's Initials (if several persons in the region collect this data) Record of all measured field parameters and their respective values.

In-situ Measurement Temperature (0C) pH Dissolved Oxygen (mg/L) Conductivity ( mhos/cm , mS/cm) Salinity (ppt) Chlorine Residual (mg/L) Secchi Disc Transparency (meters) Significant Precipitation Flow (ft3/s) Turbidity (NTU , JTU)

pH A scale that denotes how acidic or basic a substance is pH A scale that denotes how acidic or basic a substance is. Pure water has a pH of 7.0 and is neither acidic nor basic.

PARAMETER PENCEMAR UTAMA B O D C O D T S S TSS Turbiditas Minyak Radio aktif Mikro organisme

Mikro organisme What is E. coli and where does it come from? E. coli is a type of fecal coliform bacteria commonly found in the intestines of animals and humans.  E. coli is short for Escherichia coli.  The presence of E. coli in water is a strong indication of recent sewage or animal waste contamination. Sewage may contain many types of disease-causing organisms.

REAKSI BOD The Reaction Expression - Which can be expressed analytically as:  CnHaObNc + (n + a/4 - b/2 - 3c/4) O2  ---->  n CO2 + (a/2 -3c/2) H2O + cNH3

BOD520

Biochemical Oxygen Demand Referred to as a “standardized laboratory procedure used to determine the relative oxygen requirements of wastewaters, effluents and polluted water” - Standard Methods (1998) widest application in management of waste loadings to sewage treatment facilities measures the molecular oxygen utilized during a specific incubation period for the biochemical degradation of organic material and oxygen used to oxidize reduced forms of nitrogen (nitrogenous demand) works best at pH 6.5 - 7.5 (mariculture????)

BOD Bacteria and other microorganisms use organic substances for food as they metabolize organic material, the consume oxygen organics are broken down into simpler compounds such as CO2 and H2O energy released is used for growth and reproduction

BOD When this process occurs in water, the oxygen consumed is dissolved oxygen if oxygen is not continuously replaced, the D.O. level will decrease as the organics are decomposed by microbes rate of decline approximates 0.20 mg O2/L/hr (Boyd, 1990) in ponds the need for oxygen is referred to as “biochemical oxygen demand” not: “biological oxygen demand”

BOD Organic waste in sewage is is one of the major types of water pollutants impractical to isolate and identify each specific organic chemical and determine its concentration BOD is an indirect measure of the total amount of biodegradable organics in the water more organics = more BOD exerted

BOD Complete decomposition of organic material by microorganisms takes time: (approx. 20 days under normal conditions) the total amount of oxygen required to “stabilize” all biodegradable organic compounds is the UBOD or BODL amount expressed in mg/L of oxygen levels sometimes in excess of 1,500 mg/L normal sewage levels = 200 mg/L

PENGUKURAN BOD 5 days a 20oC 300 mL glass BOD bottles two D.O. readings: initial and after 5 days’ incubation in dark at 20oC BOD = D.O.Day 0 - D.O.5days very clean waters = BOD5 of 1.0 mg/L sewage level = BOD5 greater than 10 mg/L

COD This refers to chemicals present in the water that are not biodegradable by microbes or are at least slowly degraded measures all organics, including the biodegradable (BOD) fraction) it is the amount of a specific oxidant (potassium dichromate) that reacts with the sample under controlled conditions So? Chemical not biological reaction