CHAPTER V, SECTION 4 SECTION 4 WATER SYSTEMS FRESH WATER SYSTEMS. The major main- tenance work for the fresh water systems con- cerned the upkeep of the distillation units. This equipment required constant observation during operating periods for signs of steam or water leaks and mal-functioning of equipment. Periodic removal of the salt scale formation was required; removal was generally accomplished after approximately 300 operating hours for the 600 gph units, and 150-200 hours for the 150 and 200 gph units. This salt scale was removed by circulating through the system a mixture of two parts of 33 percent muriatic acid and one part of 75 percent phosphoric acid. Retubing of the older 600 gph units became necessary and repairs were started; by 20 April 1954, two units at site Elmer and two at site Fred had been retubed. The wall thickness of the tubes in these evaporators was materially reduced by corrosion so that tube leaks developed frequently. The following tabulation shows the condition of tubes prior to retubing of the four units. by on-the-job- manufacture and by substitution of engine parts from other makes. These engines were old and required continuous observation and frequent overhaul. It was the practice to maintain (at site Tare) overhauled spare engines for immediate replacement as the need arose. Very little maintenance was required on the fresh water distribution system. However, continued vigilance for indications of leaks in the underground system was essential as leaks ordinarily did not show on the surface due to the permeability of the coral formation of the atolls. Water consumption was checked daily and closely watched during the hours between midnight and 0400. A sharp unaccountable increase in consumption usually indicated a leak. When this condition ocurred, the system was checked by isolating sections and applying air pressure of 95 pounds per square inch to the system. If a leak was in the system it was read- ily indicated by a quick drop in test pressure and by blowing to the surface. The bolted steel fresh water tower tanks, both at site Elmer and Fred, survivals from OPERATION GREEN- NUMBER OF LEAKS AT TIME OF TUBE WALL THICKNESS RETUBING was initiated for their renewal. SITE UNIT NEW MIN. Elmer DI-22 .049 .016 Elmer DI-53 .049 .018 Fred DI-56 .049 .016 Fred DI-63 .049 .022 water of the same composition as sea water, were, in general, more satisfactory as a source AVG. .033 .036 .036 .040 MAX. .039 .040 .044 .045 12 11 10 13 When overhauling evaporators, all auzxili- ary equipment such as heat exchangers, vapor compressors, water level controls, pumps, etc. were opened for inspection and repaired as found necessary. Central lubricating oil systems were installed at both site Fred and Elmer. This lubricating system considerably reduced difficulties formerly experienced in the lube oil systems of the vapor compressors. The installation of brine blow-down pumps made of stainless steel in lieu of the pumps of copper alloy formerly used decreased considerably the brine pump overhaul requirements. Acquisition of “‘Airtool’ tube rolling equipment resulted in better tube HOUSE were in poor condition and a project SALT WATER SYSTEMS. Salt water wells penetrating beyond the brackish range into of supply than were direct intakes from the lagoon. The water taken directly from the lagoon continually carried marine growth from the sea and trash from ships; this accumulated on screens or strainers. On one occasion, the supply of sea water at site Fred failed due to clogging of the system by the accumulation of small fish on a check valve. Maintenance difficulties experienced with wells seemed more temporary. When wells were first placed in operation, the system suffered from accumulationsof silt and, in some cases, contam- ination with organic matter. However, after the wells were in operation for several weeks, these conditions generally cleared up. A rather unusual condition was experienced when the new well the reduction in wall thickness in rolling was absolutely controlled and the work was at site Fred wasfirst placed in operation. This well was fouled with a soft, white organic growth which appeared to come from a 30-inch local lateral which functioned as collection sump in the coral formation. This became very thick The Universal engines driving the vapor compressors of the “Badger Units” are no longer changers. A charge of three pounds of ‘“Perchleron’’ (active ingredient Calcium Hypochlorite rolling with a resultant increase in the useful life of tubes. With the use of this equipment, more rapidly accomplished. manufactured and this interjected a difficult spare part problem. This was solved somewhat Page 5-4 and plugged pump suction strainers, caused foaming in evaporators, and fouled the heat ex70%) was placed in the well which caused the organic matter to rise to the surface of the water