Deformation monitoring a territory of fluid industrial wastes burial

The project of deformation monitoring for region of fluid wastes burial was developed by Institute of<br>Physics of the Earth. Precise leveling, GPS-measuring, seismic acoustic, geochemical as well as periodic<br>gravimetric observations are included in the package of geodetic observations. The observational network of<br>the ecological geodynamic polygon enables monitoring deformation processes in territory about 35 sq. km.<br>Since 1998 repeated geodetic measurements are carried out at the polygon with average accuracy: for<br>leveling - h = ± 0.7 mm / km, for GPS-measuring - σX = (1.3±0.4) mm, σY = (1.2±0.4) mm, σZ = (1.8±0.5)<br>mm. The results of geometrical leveling revealed following features of vertical motions at the polygon:<br>presence of reciprocating motions differentiated with respect to area amplitudes of which (from -8 mm to 15<br>mm) considerably exceed errors of measurements for some periods; predominance of low-amplitude (less<br>than 4 mm) downward movements in some periods close to injection area; the velocities of the motions<br>averaged over the full interval of observations do not exceed 1 mm per year. The analysis of processing data<br>of GPS-monitoring at territory of the polygon allows noting presence of reciprocating horizontal motions<br>differentiated with respect to area of movements whose absolute value of a vector for different periods<br>between observations can change up to 30 mm. The absolute value of a vector of velocity in averaging for 4<br>years time of observations does not exceed 4 mm per year. Some stations keep alignment of movements in<br>time, some stations do not. The investigations carried out during several years demonstrate that the applied<br>optimum complex of deformation monitoring allows detecting and studying causal and consequent<br>connections between deformation processes and fluid industrial wastes injection carried out. The authors<br>consider that the applied technique and the package of geophysical methods could be successfully used for<br>monitoring ecological safety at oil and gas fields mining, in region of industrial wastes burial, in regions of<br>atomic power plants location etc. as well.