ABSTRACT:In hydrogeological research studies, long-term constant flow pump tests are used as a common method for

determining aquifer parameters. After the well development studies is completed in newly drilled wells, a preliminary

analysis process of the well’s interaction with the aquifer should be carried out by conducting a step drawdown test.

Aquifer transmissivity (T) and the well loss parameters (C) should be determined by analyzing step drawdown

test at variable discharge rate. Thus, for long-term pump testing, accurate pump selection and more reliable

information about the transmissivity (T) of aquifer can be obtained. In this study was conducted within the borders of

Himmetdede in Kayseri province, and many observation wells and dewatering wells were opened within the project

area in order to contribute to the dewatering works of the enterprise carrying out mining activities and to reveal the

hydrogeological structure. Constant rate pump test and step test results in SK-1 dewatering well, which is thought

to be important for open pit mine dewatering studies, are discussed in this study. Aquifer transmissivity (T) and well loss coefficient (C) values were calculated using different analytical solution methods. Analysis of long-term pump

testing using different numerical methods is presented. Comparisons of the results were made and the contributions

of both analytical and numerical methods to the solution of aquifer parameters were presented.