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The last item in Table 4-1 may be commented on. All drilling debris produced during drilling(percussion drilling as well as core drilling) was collected in the sedimentation containers of thereturn water system, see Figures 3-3 and 3-6 (except the finest fractions which stayed suspendedin the discharge water from the third container). The collected drill cuttings from the core drilledpart were weighed after completed drilling in order to obtain a measure of the drill cuttingsrecovery.4.3 Data handling4.3.1 PerformanceMinutes for several items with the headlines Activities, Cleaning of the equipment, Drilling,Borehole, Core drilling penetration rate, Deliverance of field material and Discrepancy reportwere filled in by the field crew, and collected by the Activity Leader, who made a control ofthe information and caused it to be stored in the SKB database SICADA.4.3.2 NonconformitiesNone.4.4 Environmental programme4.4.1 PerformanceA program according to SKB’s routine for environmental control was followed throughout theactivity. A checklist was filled in and signed by the Activity Leader, who also filed it in theSKB archive.4.4.2 NonconformitiesNone.4.5 Additional workTo ensure that instruments used in the measuring and monitoring program can pass between theupper, wide section and the lower slim part of the telescopic borehole, a stainless steel cone wasinstalled in the transition between the two units of borehole KFM06C. Finally, the borehole waslogged with a dummy to ensure that the borehole was free from obstacles before the drilling rigwas removed.Even if the quality program was applied as described above and borehole KFM06C wasapproved, it later turned out that some metal material still remained in the borehole. Deviationmeasurements and geophysical logging could be carried out without problems in KFM06C.However, during descending the BIPS-probe in the borehole, an obstacle was encountered,and the logging had to be interrupted. The obstacle was identified with a borehole cameraas iron threads, which probably had come loose when lifting the inner support casing (seeSection 3.3.2). The circular threads were probably resting on bottom of the transition cone,and just happened to follow the BIPS-probe into the slim borehole. To solve the problemtemporarily, the threads were pressed to the borehole bottom by using a heavy weight,whereafter the BIPS-measurements were completed.27