Water Supply Problems in Alaska— Alter 



233 



is minimized. Figures 5 and 6 show an Arctic well installation 

 and details of weather protection. An electrical heating cable 

 is used in this installation to prevent freezing of the casing. A 

 well house is also placed over the well and a pit which might 

 disturb the thermal regime of the ground as well as increase the 

 chances of contamination of the supply has been eliminated. 

 A mastic seal is placed in the annular space between the well 

 casing and the pump house floor. 



A submersible type deep well pump installation has been 

 suggested for use in low temperature areas. The suitability of 



Tee 



Scnsit 

 But* 



I" THICK WOOL 



reLT MPe IN- 

 SULATION FOB 

 4" CAOINS 



Thermostat Pen 

 Automatic cont*< 



Surface. 



CONV. 



OuTier 



St 



To PUMP 



Pitch Pipe 



TO PELL 



WELL PIPING DETAIL 



Fig. 6. 



this type of equipment for use under such conditions is not 

 known. Figure 7 shows a submersible type pump. 



Structures such as settling basins, filters and clear wells may 

 conduct significant amounts of heat to the surrounding soil 

 unless proper insulation and construction measures are fol- 

 lowed. The result in permafrost is that ground water may 

 accumulate around the structure and thus destroy stability. 



Figure 8 shows a comparison of annual degree days for cities 

 in temperate climates and for selected points in the low tem- 

 perature regions. A glance at this chart further emphasizes the 

 significance of the problem of heating water supply facilities 

 under low temperature conditions. 



