On 23 January, Sirius Minerals Plc announced the completion of coring at SM2, the second new borehole completed at the York Potash Project. Drilling of SM2 (Howlett Hall) commenced on 2 September 2011, with a successful change from the smaller top-hole rig (which was then moved to SM3) to the larger coring-rig on 8 November 2011. A series of fluid-loss-zones were encountered during the drilling of the section between about 947 metres and 1,175 metres. This slowed the progress of this hole as each loss zone was repaired to enable drilling to proceed. Due to the delays and ongoing losses, the decision was made to not core the Boulby and Sneaton sylvite seams. Coring of the critical Fordon Evaporite section was commenced on 13 January 2012 and successfully completed on 21 January 2012, proceeding from 1,412 metres to 1,598 metres below surface with 100% recovery.
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