r - part - usaid
r - part - usaid
r - part - usaid
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In bath project areas, z total of 15 days of full time rig<br />
use is assumed fay- praduetf~n wells, and 2.9 days Ear exploratory<br />
walls, This ope:ation Includes sstti~g the surface casing,<br />
drilling an 8" hi~fe, seasing the Sola, sagzing the screeE aad<br />
casing, and dsuel+npixg the hol~, The times assumed are the same<br />
in each region de~;pi+a %he depth in the Central Range being, on<br />
average, 30n qreatsr. The coxistent hardness of the limestone<br />
enca~ntered in the Bay Region compensates for the wider variety<br />
of 1Fthulogies i~ncanfitizred in the Central Range. As is<br />
consistent throughaut the ~zodef, total travel time allowed is 2<br />
days in the Bzy 3cgion z ~ d 4 days ia the Centr~L Bange.<br />
T3e tors: time taken ta dri31 the borehale, ;ass zbe travel<br />
time arid the actuzf Criliing tine reprssefits the l@downtimem.<br />
This is conputed in the figures shovn below.<br />
Pr~duc.tic2 Mcl is Exploratory Sells<br />
Bay Regt Central Range say Keg. Central Bange<br />
Tala1 days<br />
allowed: 35 57<br />
less travel<br />
tinr.~ : 2 4<br />
Days at site: 33 53<br />
Days driX3ing 15 15<br />
- CI<br />
-------------a"-----<br />
Downcine : AG 38<br />
-----------------dm<br />
55% 72%<br />
The reasons fcr this high figure of downtixce are discussed<br />
elsewhere in the report, Sut are zainly due to mechanical<br />
breakdowns, fuel sh~rtaq~zs, and logistical pr~blems, The<br />
greater Ggwntfza experienced in the Central Range operations is<br />
a rsf%eeticn 0% the increased distance to the site necessary to<br />
provide either fuel or repairs.<br />
A further difference in the c~st of operating in the two<br />
regions is in the amczct of casing lost in exploratory<br />
borehoies. In tke Bay Region, this averages 3Cm for each<br />
borceEloLe ! -y-r=rdix A ~ - ~ 4.4.1, ~ ~ "able ~ 3 3 IF the Central Range the<br />
average is 10Gm fhpendix 6.4.2, Table 3). In the hard<br />
limestone 05 the Bay 3egion, the success of a borehole can be<br />
brozdly determined before czsing Is installed. In the Central<br />
Range, however, it is more often necessary to seal off the upper<br />
par", of the hole fro3 saline wazer iz order to deternine whether<br />
potable water is fouzd at greater depths.<br />
The greater distances involved iri operating in the Central<br />
Range increases the nu~"&er of vehicles required as well as the