Three borehole logs are presented that describe the material excavated from a slag deposit in Consett Co. Durham (ad pdf files). The boreholes were created by GeoSonic Ltd commissioned by Cardiff University in September 2017 as part of a UKRI funded project that explores CO2 uptake in slag. The drilling penetrated through 20 and 25m of material representing the extent of the heap to underlying natural ground. The methods used and samples recovered are described in Pullin et al., 2019 Environmental Science and Technology. 53 (16) 9502-9511. DOI: 10.1021/acs.est.9b01265. The deposited data include photographs of recovered material from one of the boreholes.