A deepest-depth measurement was made at 30 cm above the water surface. Following this, the water was agitated by rapidly dunking a specimen jar into the water 10 times to a depth of around 15 cm prior to collecting a water specimen, to observe and record the color and odor. Then the deepest-depth atmosphere measurement was repeated. Data on ambient conditions (climate, surrounding soil type, other surrounding features, well-construction material and design, presence, type and position of pumping system) were observed and recorded. Owners of each well were subsequently interviewed to obtain information on the use of the well (purpose, well age, frequency of use, frequency and timing of well maintenance work, type of pumping system, etc.) and the information was recorded on a data form.