drawings and specifications. You may be asked to submit information (fact-gathering package) on a new power distribution addition to the base. If so, the following recommended actions need to be considered: Install  utility  poles  in  the  same  location, especially on upgrade projects. Install power distribution systems underground whenever possible. Conduct a survey using a map to chart the territory where the distribution lines are to be routed  (for  large  areas,  aerial  photography  is faster and more accurate). Ensure that the survey map is large enough to clearly show all buildings. roads. streams, hills, ridges.  railroads.  bridges.  and  any  existing power and communications lines. Select   the   straightest   and   shortest   route whenever possible. Route the new distribution system near or in the general direction of future load demands. Make the distribution system readily accessible for  construction.  inspection,  and  maintenance  by paralleling  them  to  existing  streets  and  highways. Avoid crossing hills. ridges, and swamp areas whenever possible to reduce the possibility of lightning and wind damage. These areas also increase costs because additional materials are needed and maintenance will be more difficult. Coordinate  with  communication  companies  to prevent the induction of interference with their existing  lines. Select a route that is away from residential areas and does not damage the environment. Keep major traffic routes free from primary, circuits. especially in nonindustrial areas. Keep-distribution lines on the same side of the road whenever possible. Avoid  blocking  driveways,  entrances.  exits.  and fire escapes when installing branch lines or guys. Locate poles 2 feet from the curb. Finally. plan for future street-lighting circuits. EQUIPMENT 4-4 Many  different  types  and  makes  of  overhead distribution equipment are in use today. This chapter will cover some of the standard equipment you will install  and  maintain,  such  as  poles,  transformers, capacitors,  interrupting  and  protective  devices. Poles Utility poles that support electrical lines must be designed to support the conductors, insulators, and shield conductors in a manner that provides adequate electrical  clearances.  A  safe  clearance  must  be maintained   when   the   conductor   temperature   is elevated as a result of a large amount of current flowing in a circuit and also when the conductors are ice coated or strong winds are blowing. The three most common types of poles that you will be working with are wood, reinforced concrete, and steel.  Other  types  of  poles  in  use  are  as  follows: aluminum,  fiber  glass,  and  polysil.  As  a  Seabee assigned to either a PWC or a battalion, you will be responsible for ordering, installing, and maintainingthe utility  poles. Power lines supported by wood-pole structures are generally considered to be the most economical. In the United States, the southern yellow pine, western red cedar, and the Douglas fir are the most commonly used species  of  tree.  All  wooden  poles  are  given  a preservative treatment (normally pressure treated) to prevent deterioration. The service life of the utility pole can be doubled by preservative treatment. Many of the older poles now in use were treated with creosote. CAUTION Creosote is a toxic compound that irritates the skin and sometimes causes blistering. It is also carcinogenic and is being phased out because of  groundwater  contamination  problems. Used creosote contaminated poles may not be burned  and  must  be  disposed  of  in  EPA approved landfills. You should use extra care when  working  around  poles  treated  with creosote,  avoid  prolonged  skin  contact,  and wash  thoroughly  after  handling.  Clothing contaminated   with   creosote   should   be laundered separately from family clothing. Creosote  oil,  pentachlorophenol,  and  chromated copper   arsenates   have   been   used   to   provide   a preservation treatment of wood poles. Newer poles are now treated with less toxic chemicals and, therefore, are safer to work with and also easier to climb (because the  treatment  softens  the  wood).  They  are environmentally  acceptable  because  they  do  not contain materials that are toxic to mammals.