Dear friends, We are drilling bore wells in our project area in Indonesia. The bore well will be drilled into a sand/gravel aquifer. Historical experience from a near by located wells is that we will get a water source at 400 ft - 450ft. I need some inputs for designing and opting type of casing pipes. Some of near by wells have opted for steel pipe, but they are costly and will start corroding after some time. (That is what some available literature says). Can you please guide me about what are the types of casing suitable to our site? Are there any rule of thumb to follow? We will be hiring agencies for drilling the wells, but I need to have good knowledge well in advance about my requirements. Thanks.