oa Storage Site Candidate for Belchatow Demo Plant

The Budziszewice-Zaosie (B-Z) structure is located 60 km NE of Belchatow, in central Poland. This is the best explored structure out of three potential storage sites for Belchatow demo plant till now because within the structure contour 6 wells penetrating reservoirs in question appear and there are 9 seismic lines of sufficient quality (6 old, 3 relatively new). Two remining structures will be explored soon by reconnaissance seismic survey and single research wells. The Belchatow demo plant is expected to provide 1.8 million ton of CO2 yearly for geological sequestration after 2015, for a period of at least 25 years, which makes at least 45 million tonnes of CO2. The principal reservoir is of Lower Jurassic, precisely Synemurian and Upper Pliensbachian sandstones, and the main seal is of Lower Toarcian shales which are relatively homogeneous and undisturbed. The reservoir properties are good according to new and archive analyses of drill core samples and well logging interpretation – porosity is of about 20% and permeability of hundreds mD. The secondary reservoir is of Lower Triassic (Buntersandstone). The static model was constructed archive structural maps and results of reinterpretation of seismic sections, including horizons from the terrain surface to the top of Zechstein. In case of seismic interpretation velocity model was based on data from 6 wells. Facies interpretation was carried out where possible. The storage capacity of the structure calculated for static and models is within the range of 100-500 million tonnes, depending on which reservoirs are considered. In case of dynamic modelling a number of approaches (software packages, assumptions) was used and test injection within one well together with full scale injection in 1-4 wells were simulated. The geological risks evaluation involved the fact of low salinity of brine (but according to geochemical analyses and paleontology the possible infiltration of potable water into the reservoir is definitely not of recent origin) and inhomegeneity of the seal between two Lower Jurassic reservoirs (this secondary seal practically ceases to exist at the topmost part of the structure) and partly of the Upper Pliensbachian reservoir. As the next step of the site investigation a baseline monitoring is proposed. In a network of profiles at the injection site of 100 sq. km area high resolution seismic, electromagnetic and gravity survey are planned. Apart from measurements within the wells, around the wells geochemical and geophysical subsurface monitoring and biomonioring is proposed.