stream through the engines (some not fitted with heat exchangers) and back into a make-up sump, with eventual discharge back to the stream. To cope with the previously mentioned increase in 1978, two 600-kw and one 800-kw portable units are being connected into the main switchboard (Fig. 5). The reason for using mobile units, which are more expensive to operate, is that they will tide us over until five Ruston Hornsby 9 ATC engines (Fig. 6) currently operating at Clinton Creek become available in mid 1978 when that property ceases operation. Besides generating electricity, the powerplant runs compressors which are rated at 1000 and 650 cfm respectively, with the air being piped to different locations in the plant. Because of increased usage, a new 1200-cfm compressor is contemplated for next year. Steam is generated in two ways — by eight waste- heat boilers on the diesel generator engine exhausts and by two 200-hp package boilers. Both systems feed a steam header maintained at about 50 to 80 psi. Each of these systems produces about half of the total re- quirement. Electrical (Fig. 7) The majority of the distribution around the plant- site and townsite is 2300 volts, which is stepped down to 550 volts and 110 volts for supplies to motors, heating, lighting, etc. Electricity supply to the mine is at 24 kv via a step-up transformer outside the powerplant. The reason for this is to minimize losses on the long transmission line to the open pit. Main distribution within the pit is at 4160 volts. The electrical department is split into three sections — mine, mill and plant — to cover the area fully. Those sections covering the mine and mill have elec- tricians available on a three-shift, seven-day/week basis. The number of personnel and responsibilities of the electrical section have increased over the years in line with increased reliance on electrical power. This is particularly true in the mine area, as shovels and drills have changed over from diesel to electric power. Be- cause the townsite is also supplied and serviced by the company, and the number of residences has increased, this area is now taking a considerable amount of time. The power requirement of the town has increased by 65% in the last twelve months! Plumbing and Sewage Water for the townsite is supplied from a single pumphouse equipped with one 75-hp and two 30-hp pumps, with a back-up diesel unit in case of power failure. Total pumping capacity is 875 gpm. At one time, this pumphouse also supplied cooling for the powerhouse, but this water is now supplied from a separate pumphouse. Water distribution throughout the townsite is supplied via a 6-in. main line with 4-in. branch lines. The unused water is returned to the stream. Pressure is maintained at 60 psi by a pre-set pressure-regulating valve at the outlet. Because of the extreme winter cold, any water lines which are not run with steam lines have to be buried to at least 8-ft (2.44 m) to combat freezing. The majority of the sewage is handled using either individual or collective septic tanks; good natural drainage makes this an effective system. A single 25,000-gal.-per-day sewage treatment plant handles effluent from the kitchen, the laundry and some of the single quarters. Garbage collection is handled by the company using a modern compacter truck which delivers to the gar- bage disposal area. The process utilizes specially made bulk containers in both the plant and townsite. Use of such modern equipment speeds up service and reduces manpower requirements. Shops The machine shop, carpenter shop and equipment shop are all well equipped with machinery to make re- placement parts on site when necessary. Because of the lack of entrepreneurs within the district, special arrangements are made to perform machining and carpentry work for outsiders. Modernization in shop layout, lunchrooms, lighting and ventilation systems has been one of the recent improvements. The machine shop includes lathes with up to 28-in. swing and 120-in. bed, broacher, shaper, rolls, welding and cutting facilities, and even a small forge. Although the capital cost of this equipment is high and its util- ization is low, the money saved by being-able to make parts for production machinery (air-freighting a part may take a week) more than justifies the expense. Pick-ups and other service and small production vehicles are maintained in the equipment garage. The small truck fleet numbers 54 and the additional trucks and vehicles 30, including 980 Cat. loaders and a Cat. 14G grader. To lessen the inconvenience of losing an item of production transport on day shift, the shop works two shifts to enable pick-up trucks to be serviced when they are not normally in use. Carpentry requirements vary from making signs to cabinet making. The shop is equipped to meet all requirements and also has a paint bay which will ac- commodate objects up to the size of a pick-up truck. Maintenance Control Maintenance control is effected by way of a work- order system. A person requiring a task to be per- formed by a maintenance crew initiates a work order. Depending on the nature and extent of the work, cer- tain approvals must be obtained from the departments involved before the job starts. One copy of the work order goes to the supervisor performing the task, one copy goes to the maintenance planner and one remains with the originator. The fore- man uses his work-order backlog to set priorities, plan the daily assignments for his crew, requisition mate- rials, and determine his manpower and overtime re- quirements. The planner uses a copy of the work order to maintain records of work in process and work backlogs. On completion of a job, the field copy of the work order is sent to the planner, who then can gener- ate data on repair costs and frequencies and report on changes and modifications. A preventive maintenance scheme has been intro- duced in the mill which will be the basis for control of all repetitive inspection and repair on mill produc- tion machinery. A base frequency of eight weeks was adopted on most of the equipment and check sheets are issued to coincide with the regular weekly shut- down day. Major maintenance work is scheduled on a longer frequency, such as annually or semi-annually. Although this program currently represents a theoret- tical approach to scheduled maintenance, its real worth will be realized as changes in content and frequency are made in response to equipment problems and malfunctions. — 50 —