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S. S. Anthony

Publications and source records attributed to S. S. Anthony.

7 recordsLinked to original sources
USGS2002

Spatial and temporal variability of trace element concentrations in an urban subtropical watershed, Honolulu, Hawaii

Trace metal concentrations in soils and in stream and estuarine sediments from a subtropical urban watershed in Hawaii are presented. The results are placed in the context of historical studies of environmental quality (water, soils, and sediment) in Hawaii to elucidate sources of trace elements and the processes responsible for their distribution. This work builds on earlier studies on sediments of Ala Wai Canal of urban Honolulu by examining spatial and temporal variations in the trace elements throughout the watershed. Natural processes and anthropogenic activity in urban Honolulu contribute to spatial and temporal variations of trace element concentrations throughout the watershed. Enrichment of trace elements in watershed soils result, in some cases, from contributions attributed to the weathering of volcanic rocks, as well as to a more variable anthropogenic input that reflects changes in land use in Honolulu. Varying concentrations of As, Cd, Cu, Pb and Zn in sediments reflect about 60 a of anthropogenic activity in Honolulu. Land use has a strong impact on the spatial distribution and abundance of selected trace elements in soils and stream sediments. As noted in continental US settings, the phasing out of Pb-alkyl fuel additives has decreased Pb inputs to recently deposited estuarine sediments. Yet, a substantial historical anthropogenic Pb inventory remains in soils of the watershed and erosion of surface soils continues to contribute to its enrichment in estuarine sediments. Concentrations of other elements (e.g., Cu, Zn, Cd), however, have not decreased with time, suggesting continued active inputs. Concentrations of Ba, Co, Cr, Ni, V and U, although elevated in some cases, typically reflect greater proportions attributed to natural sources rather than anthropogenic input. ?? 2002 Elsevier Science Ltd. All rights reserved.

Applied Geochemistry↗
USGS1996

Hydrogeology and ground-water resources of Kahlap Island, Mwoakilloa Atoll, State of Pohnpei, Federated States of Micronesia

The lens of fresh ground water on Kahlap Island contains about 21.3 million gallons of potable water. Recharge to the freshwater lens is estimated to be 125,000 gallons per day on the basis of a mean annual rainfall of 120 inches. The long-term average sustainable yield is estimated to be about 17,300 gallons per day. The estimated demand for water is about 13,500 gallons per day. Shallow-vertical-tube wells or horizontal- infiltration wells could be used to develop the freshwater lens. The effect of development on the lens can be determined by monitoring the chloride concentration of water from a network of shallow- water-table and deep driven wells. The ground- water resource on Kahlap can be used in conjunc- tion with individual rainwater-catchment systems: rainwater can be used for drinking and cooking, and ground water can be used for sanitary uses. When rainwater-catchment systems fail during extended dry periods, ground water would be available to meet the total demand.

Water-Resources Investigations Report↗
USGS1996

Hydrogeology and ground-water resources of Pingelap Island, Pingelap Atoll, State of Pohnpei, Federated States of Micronesia

The lens of fresh ground water on Pingelap Island, Pingelap Atoll contains about 384 million gallons of potable water. Recharge to the freshwater lens is estimated to be 230,000 gallons per day on the basis of an average annual rainfall of 160 inches. The long-term average sustainable yield is estimated to be about 69,000 gallons per day. The estimated demand for water is about 50,000 gallons per day. Shallow-vertical-tube wells or horizontal-infiltration wells could be used to develop the freshwater lens. The effect of development on the lens can be determined by monitoring the chloride concentration of water from a network of shallow-water-table wells and deep driven wells. The ground-water resource on Pingelap can be used in conjunction with individual rainwater-catchment systems: rainwater can be used for drinking and cooking, and ground water can be used for sanitary uses. When rainwater-catchment systems fail during extended dry periods, ground water would be available to meet the total demand.

State of Pohnpei↗
USGS1996

Hydrogeology and ground-water resources of Ngatik Island, Sapwuahfik Atoll, State of Pohnpei, Federated States of Micronesia

The lens of fresh ground water on Ngatik Island contains about 509 million gallons of potable water. Recharge to the freshwater lens is estimated to be 990,000 gallons per day on the basis of an estimated mean annual rainfall of 160 inches. The long-term average sustainable yield is estimated to be about 280,000 gallons per day. The estimated demand for water is about 30,000 gallons per day. Shallow-vertical-tube-wells or horizontal-infiltration wells could be used to develop the freshwater lens. The effect of development on the lens can be determined by monitoring the chloride concentration of water from a network of shallow-water-table wells and deep driven wells. The ground-water resource on Ngatik can be used in conjunction with individual rainwater-catchment systems: rainwater can be used for drinking and cooking and ground water can be used for sanitary purposes. When rainwater- catchment systems fail during extended dry periods, ground water would be available to meet the total demand.

Water-Resources Investigations Report↗
USGS1989

Geohydrology of the Laura fresh-water lens, Majuro atoll: A hydrogeochemical approach

In small limestone islands, the depositional history and subsequent chemical interactions between ground water and the aquifer host rock play critical roles in the occurrence, movement, and chemical quality of ground water. The hydrogeochemistry of the Laura fresh-water lens, Majuro atoll, Marshall Islands, is an example of these relations. Laura is underlain by two principal hydrologic units. The upper unit is a back-reef-marginal-lagoonal deposit which formed during the Holocene interglacial stage. It is composed of moderately permeable carbonate sediments. The lower hydrologic unit consists of highly permeable limestone that was subaerially exposed, most likely during a Pleistocene glacial lowstand. Similar stratification is found at Bikini and Enewetak atolls. The upper hydrologic unit contains a calcium bicarbonate-rich fresh-water lens, in which a potable fresh-water nucleus as much as 14 m thick occurs on the lagoon side of the island. Storage in the fresh-water nucleus ranged from 1.70 x 10 6 to 2.08 x 10 6 m 3 during 1984-1985. Ground-water occurrence and flow are governed by an asymmetric distribution of lithofacies about the longitudinal axis of the island and an abrupt increase in permeability at the contact between the upper and lower hydrologic units. The highly permeable lower hydrologic unit contains sea water and truncates the fresh-water-sea-water mixing zone. The fresh-water lens and associated fresh-water-sea-water mixing zone are the site of continuously occurring diagenetic reactions that significantly affect the porosity and permeability of the aquifer. Non-equilibrium dissolution-precipitation reactions, coupled with variations in CO 2 input, control the chemical evolution of Laura ground water. At the present rate of chemical weathering, 465 m 3 of sediment are being dissolved and transported to the sea by ground water each year. This dissolution results in an annual increase in porosity of 0.01%. The primary factors controlling the occurrence and flow of ground water in the leeward reef islet of Laura are (1) the depositional history of the upper hydrologic unit, which has resulted in a greater accumulation of low-permeability (fine-grained) sediments beneath the lagoon side of the island and a high- to low-permeability (coarse-to fine-grained sediment) gradation between the ocean and lagoon; and (2) the diagenetic history of the lower hydrologic unit, which has resulted in a highly permeable basement.

Geological Society of America Bulletin↗
USGS1987

Ground-water resources of the Laura area, Majuro Atoll, Marshall Islands

The water system that supplies the heavily populated Dalap-Uliga-Darrit (DUD) area of Majuro atoll, Marshall Island, relies almost entirely upon airstrip catchment of rain water. Droughts cause severe water supply problems and water rationing is required, even during periods of normal rainfall. The Laura area contains a substantial lens of fresh groundwater that could be developed for export to the DUD area 30 mi to the east. Study of the groundwater resource at Laura involved a survey of existing wells, installation of monitoring wells and test holes, compilation of continuous records of rainfall and water level fluctuations, and collection of water quality data. Test hole data permitted the definition of three geohydrologic units which correlate well with similar units in Bikini and Enewetak atolls. The units consist of two layers of unconsolidated reef and lagoon sediments resting on a dense, highly permeable limestone. The potable water zone, or freshwater nucleus, of the lens is contained mostly within the unconsolidated layers, which are much less permeable than the basal limestone. Recharge to the Laura freshwater lens is estimated to be 1.8 mil gal/day, based on an average annual rainfall of 140 in. Sustainable yield is estimated to be about 400,000 gal/day. Shallow skimming wells or infiltration galleries similar to those used on Kwajalein atoll would be appropriate to develop the freshwater lens. The impact of development on the lens can be determined by monitoring the salinity in developed water and in a network of monitor wells.

Laura area, Majuro Atoll↗