Assessment of disposable groundwater resources for hydraulic fracturing of gas shales in the Lublin Basin (eastern Poland)

This paper assesses the groundwater resources for hydraulic fracturing of gas shales in the Lublin Basin in 2030. Such evaluations are useful for gas concession holders who plan the magnitude and schedule of gas production. In order to determine the disposable groundwater resources, a water management balance model was developed. The data from the balance and forecast of groundwater resources for 2030 in the Vistula River Basin were used as basic input data. The model accounts for the following specific factors determining the quantity of water resources in prospective gas exploitation areas: reduced groundwater recharge due to climate changes, unregistered water usage by individual households, demand for water associated with shale gas mining development, and the rate of water utilization for fracturing or returned to hydrological circulation. The extent to which these factors will affect the resources available in 2030 is uncertain. The study therefore analysed two environmental scenarios - a moderately rigorous and a rigorous one - assuming major climate change effects and a radical increase in the demand for water. Disposable water resources were determined for 12 separate balance zones in accordance with groundwater bodies (GWB) or their subsections located in the research area. This prediction refers to groundwater resources without stratigraphic division into aquifers. Depending on the zone, the resources will range from 1,072,735 to 79,458,310 m3/year for Scenario I, and from 733,285 to 49,103,085 m3/year for Scenario II. Gas concession holders are interested in relative values of resources expressed per area unit which, depending on the zone, will range from 10,132 to 32,300m3/(year·km2) for Scenario I, and from 5,212 to 24,200m3/(year·km2) for Scenario II. The analysis of the balance model reveals that the prediction for guaranteed groundwater resources in the balance zones of the Lublin Basin area in the year 2030 is large; thus development of shale gas mining should not negatively affect the quantity of water in this region.