SEA WATER FROM GROUND SOURCES 183 



triided iron-bearino- water may be associ- nately, owing to the settling procedure, the 



ated with the upi)er level of the coarse- constant temperature factor is lost and 



gravel stratum in which the well screen is room air-conditioning is used as a substi- 



now located. We hope to relocate the w-ell tute. When the water is ready for use 



screen at a higher point where we may find after settling, pH ranges from 7.6 to 8.1, 



sea water of acceptable salinity, but with dissolved oxygen is about 6 p.p.m., and 



a ferrous iron content below the precipi- specific conductance 28,500 micromhos (at 



tation threshold — about 3 parts per mil- 25° C). 



V DISCUSSION 



lion. 



Although we have not tested the pro- In view of its many advantages, it is 

 duction capacity of the well, it can be as- suggested that the use of a ground-water 

 sumed that the present installation, w4th source of sea water be explored when plan- 

 a larger pump and transmission line, could ning a supply system for any seaside lab- 

 produce nearly 100 gallons a minute wnth- oratory. The feasibility of a ground- 

 out excessive drawdown. water supply will depend upon local con- 

 ditions, and few generalizations can be 

 CHARACTERISTICS OF THE WELL WATER ^^^^^^^^ Cxenerally, if underlying earth 



In order to use the well water, it is neces- material is uniformly permeable and ex- 



sary to allow the ferric hydroxide to settle, tends laterally to the surrounding sea 



This has been accomplished by holding water, a sufficient supply can be obtained 



batches of water in a 2,000-gallon tank, by penetrating to a depth beneath the 



Since the flocculate is very light, requiring fresh- water layer overlying the sea water, 



a week or more from time of oxidation to There remains, as a major problem, the 



settling, this is a slow process. After set- possibility of chemical contamination of 



tling, however, the water has been used the ground-water source, 



successfully to rear eggs, larvae, juveniles. Except for the iron problem, Sandy 



or adults of 51 species of 31 families of Hook is an ideal location for a shallow 



fishes. No failure to maintain any species salt-water well. In many other areas also, 



of fish can be attributed to the quality of ground sources are used to supply aquari- 



the decanted water. Many groups of in- umg. One example is the well, described 



vertebrates (ctenophores, coelenterates, in two papers in this collection (Stras- 



mollusks, echinoderms, crustaceans) and burg, Nakamura) which was drilled into 



several species of algae also have been sue- a coral formation in Honolulu. There is 



cessf ully maintained in the well water. .^Iso a well in use at the Waikiki Aquarium 



The following analysis of the well water in Honolulu. Spencer Tinker, Director of 



(March, 1962) shows that after precipita- the Aquarium, has given us the following 



tion no iron remains in solution : information about this well : 



Parts per 



million The Aquarium stands on the edge of the ocean 



Fe in solution, after settling 0.00 j^jg^ a few feet from the water. The land under 



Mn in solution, after settling . 19 ^he Aquarium is loose unconsolidated rubble, 



Fe, before settling 4. 8 ^and, etc.. to a depth of 40 feet. From 40 feet 



Mn, before settling .29 downward for an unknown distance there is an 



SiOs, before settling 8. 8 ancient coral reef which is quite solid but which 



Chloride, before settling 10 contains scattered sand pockets and which is 



The temperature of the well water, taken permeated by sea water. The Aquarium bored 



, . , ^ . , • • X 1 a liole in this area 80 feet m depth. This hole 



durmg the occasional pumpmg mtervals .^ ^^^,^^^ ^^^^^^ ^ ^^^^^^ .^^ diameter and has the 



between September 1961 and March 1962, upper 40 feet cased with a 12-inch wrought-iron 



has remained at 56.3°d=0.2° F. Unfortu- pipe. This pipe or casing keeps the rubble from 



