The process of wells ecology drilling without a preliminary drilled soil mechanical properties assessment is studied. An analytical mathematical model of a drilling unit as the object under control has been worked out. It is shown that due to the interaction through the power plant and a drillable soil, there is a natural cross-link between the feed control contour and the drill rotation control contour, which has a significant influence on the drilling dynamics. Cross-link parameters depend on the soil mechanical properties and conditions. To compensate for cross-connection, it is proposed to use a three-level control system, with a neural network at the middle hierarchical level. The structure of the neural network has been worked out, and tasks, solved in each neuron layer, are determined. The algorithm of digital controller adjusting, allowing to achieve the optimal ecology drilling modes has been developed