INTRODUCTIONGroundwater is the most commonly found freshwater source in the world, groundwater supplies for nearly half of all drinking water requirements of the world population and about 43% of the global consumptive use in irrigation is also fulfilled by groundwater. Therefore the quality of groundwater is very important than any other water resource referring the health of human and all other living beingsPresence of fluoride and hardness excessively in ground water is considered a serious problem in public health point of view. In Sri Lanka, excessive fluoride and hardness in groundwater has proven to be a serious issue due to most of rural domestic water requirements is fulfilled by groundwater. Recent researches confirm that groundwater in districts such as Anuradhapura and Monaragala contained fluoride exceeding the desired value. Also some researches were claimed that Jaffna, Hambanthota, Vavuniya and Anuradhapura exceeding maximum level of hardness.Modified fly ash has an ability to remove toxic in water like hardness and fluoride. But modified fly ash alone is unable to remove those toxic due to their particle sizes, which has reduced its adsorption capacity and stability in water too. Therefore, modified fly ash is needed some material which has huge amount of pore in its surface for anchoring to increase their stability in water and enhances reactive performance. Graphene oxide has those characteristic mentioned above. Therefore grapheme oxide and modified fly ash composite can be a good toxic remove material. Hence, the study focuses to impregnate modified fly ash in graphene oxide matrix and evaluates the properties and performance in removal of hardness and fluoride in groundwater.STATEMENT OF THE PROBLEMExcessive hardness and fluoride cause lot of health problems recent years around the world as well as srilanka. Chronic kidney disease of unknown etiology (CKDu) is the main problem occurred. Latest research reveals that areas with groundwater containing high fluoride concentrations and very hard water overlap with CKDu affected areas. Other than that dental fluorosis, skeletal fluorosis, low IQ and mental retardation are spread due to these toxic in water.2CE4902A01_140293KSIGNIFICANCE OF THE RESEARCHWhen selecting a treating method for this kind of research, it is important to consider the cost, availability of materials, level of removal required and testing procedures. Fly ash and grapheme oxide are very easy to produce and not much expensive as well. Fly ash is a waste product of the coal power plants.Removal of water toxic is important because water or water resources cannot replace by any material. Shortage of drinking water is a major problem for several countries. In srilanka, dry zone has faced this problem for a long time. Results of this research can be useful for anyone who interested in these issues.People who live in the dry zone and agricultural areas are main stakeholders of this research. Also the industry could refer the results to improve their water treating systems.SCOPE AND LIMITATIONS OF THE STUDYConcentration of fluoride and hardness, pH and flow rate are the proposed variables to be studying in the research. Preparing graphene oxide/fly ash is the most time consuming work of the research.OBJECTIVESThere are two main objectives in this research. The main of this research is to check whether fly ash and grapheme oxide composite has an ability to reduce the fluoride and hardness level of the water to the drinking water range. Other objective is to improve the fly ash/graphene oxide composite as much as possible.Moderately hard water is approved for drinking. Fluoride concentration of the drinking water should be 0.6-1.0 mg/L.PROPOSED METHODOLOGYThere will be few steps in the research progress.1. Synthesis of grapheme oxide /fly ash composite at the laboratory2. CharacterizationIdentify the characteristics of the composite using following analysis methods.3CE4902A01_140293KI. XRD(X-Ray Diffraction)Analysis the morphological characteristic (size, shape, surface element)II. SEM (Scanning Electron Microscopy)Analysis about composition, functional groupsIII. FTIR (Fourier Transform Infrared Spectroscopy)3. Synthesis of water containing hardness and fluoride4. TestingAs the first step of testing I have to prepare 15 specimens containing prepared water 100ml. Then insert the fly ash/ graphene oxide composite 1g for each. After 4 hours filter the water and test for hardness and fluoride concentration.5. Analysis resultsI. Langmuir isothermThe Langmuir isotherm model can be represented in the form of equation as follows;Where qe is the amount of adsorbate adsorbed per unit weight of adsorbent at equilibrium (mg/g), , b is the Langmuironstant that relates to the energy of adsorption (L/mg), and Ce is the equilibrium concentration of adsorbate in solution (mg/L).In order to find out the further feasibility of the isotherm, the essential characteristics of the Langmuir isotherm can be described by an equilibrium parameter RL as in EquationWhere C0 is the initial concentration of fluoride in mg/l and RL indicates the nature of the adsorption process, as given below;• RL > 1 Unfavorable• RL = 1 Linear• 0