Compliments of JOHNIE JOHN'S


RELIABLE TIRE SERVICE, INC.

 Hannah's Rest, Frederiksted
 6 \ Ia (;rande Princesse, Christiansted











 \Ll(, 1N 1 E N 'I ( Electronic)
 \l TOM \TIC TR ANSMISSION
 1R \KE SER\ ICE







 \(MIU SS)GRAE TRES


 PREMIUM GRADE TIRES
 For Passenger, Trucks, Farm
 and Earthmovers


 POST OFFICE BOX 1523
 FREDERIKSTED, ST. CROIX
 UNITED STATES, VIRGIN ISLANDS 00840
 772-0736
 773-0736


 ALSO KNOWN FOR

 DEPENDABLE

 SERVICE


tense, but of short duration, followed by sunshine and the con-
tinual tradewinds. The vegetation generally holds the water for a
short time without rapid percolation. The sun comes out and
begins to evaporate the surface water. At the same time, capillary
action within the upper soil layers acts like a wick to bring per-
colating water back for evaporation at the surface. As the water
evaporates, minerals contained are left behind and are concentrated
in the remaining water and in the soil profile. The evaporation of
rain water from the soil profile results in a large build-up of chlor-
ides which originate from the sea and are mixed with the rain.
Other major constituents which are added by this type of concen-
tration are sodium (Na) and sulfate (S).

POTABLE, RECLAIMED AND SURFACE WATER
 Other water sources on St. Croix can also be used for irriga-
tion and hence their quality is of some concern here. Potable
desalinizedd) water is of good quality, however its cost generally
makes its use for agriculture uneconomical. Surface water (streams.
dams) is also low in salts, boron and carbonates. but like cistern
water it is often scarce due to drought when it is needed the most.

 Reclaimed water (sewage effluent) has long been used for
crop irrigation in water short areas and its use on St. Croix could
be beneficial in several ways. The use of reclaimed wastewater for
the artificial recharge of the groundwater would be one method
for increasing both the quantity and quality of St. Croix's water
supply. Reduced salt concentration and prevention of saltwater
intrusion are possible benefits. The most serious problem with the
reuse of water comes from the total dissolved solids (especially
chloride) which will affect its possible use for both drinking and
agriculture. The concentration will depend on the source and da\-
to-day fluctuations at specific locations.

 Reclaimed wastewater with a controlled chloride and sodium
level could be used for irrigation. A well managed irrigation system
using a mix of irrigation water and sewage effluent can reduce the
pollution potential as compared to disposal in rivers and other
water bodies.

IRRIGATION
 Water used for irrigation always contains measurable quan-
tities of the dissolved substances previously mentioned, which aie
generally referred to as salts. The amount and kind present will
determine the suitability for irrigation. The problem that results
from using a poor quality water will vary locally as to the kind
and degree. Micro-climate, geology and the amount and distribu-
tion of precipitation throughout the year are the key influences
on St. Croix. The most common problems on St. Croix involve
salinity and permeability.

SALINITY
 A salinity problem due to water quality occurs if salts from
the applied irrigation water accumulate in the crop root zone and
yields are affected. If two identical soils are at the same degree
of wetness (soil water potential) but one is salt-free and the other
is salty, the crop will be able to use and extract more water from
the salt-free soil.

 With shallow water tables, a salinity problem may also exist
due to upward movement of water and salts from the groundwate'
as the water evaporates from the soil or is used by the crop. This
mechanism was previously mentioned in the discussion on salt
accumulation in the groundwater. Such a salinity problem is
related to high water tables, lack of soil drainage and a high evapo-