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From June 1987 through May 1988, we collected reports of injuries among 5300 children who attended 71 day-care centers in Atlanta, Ga. One hundred forty-three injuries severe enough for the child to require medical or dental care were reported, including 63 lacerations (44.1%), 23 fractures (16.1%), 5 crush injuries (3.5%), 4 dislocations (2.8%), 2 human bites (1.4%), and 2 concussions (1.4%). The head was the site of 98 (68.5%) injuries. Peak hours for injuries were 11 AM and 4 PM, the peak day was Monday, and the peak season was summer. After adjustment for hours and dates of attendance, the rate was 1.77 injuries per 100,000 child-hours in day care; among preschool-aged children, infants had the lowest rate (0.77) and 2-year-old children had the highest rate (2.26). Almost 47% of injuries occurred on the playground; falls were involved in 70% of such injuries. Because 33% of all injuries resulted from falls on the playground, impact-absorbing playground surfaces may be a possible intervention to reduce injuries.

Hydraulically placed cemented tailings, with a 30:1 tailings–cement ratio, have been used to backfill large blast-hole stopes at Fox Mine in Northern Manitoba. Heavily reinforced concrete bulkhead supports were provided to prevent intrusion of hydraulic fill materials into the mine drifts. Instrumentation was installed through several of these bulkheads to measure horizontal stresses on the bulkheads and pore water pressures at several points in the fill. Fill quantities, fill levels, and water balance were monitored in conjunction with the instrumentation. Measured bulkhead stresses were much less than anticipated due, apparently, to the effects of arching and cementation. Timber bulkheads, designed on the field measurements, were found to perform satisfactorily in subsequent stope pours. Backfill drainage appeared to follow the general predictions made from laboratory permeability tests on control cylinders.

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