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A. J. Roman-Mas

Publications and source records attributed to A. J. Roman-Mas.

4 recordsLinked to original sources
USGS1994

Reconnaissance of ground-water quality at selected wells in the Beaver Creek watershed, Shelby, Fayette, Tipton, and Haywood Counties, west Tennessee, July and August 1992

A reconnaissance of water-quality conditions of the water-table aquifer in the Beaver Creek watershed and other rural areas of Shelby, Fayette, Tipton, and Haywood Counties, Tennessee, was conducted during July and August 1992. The reconnaissance was conducted by the U.S. Geological Survey, in cooperation with the Tennessee Department of Agriculture and the University of Tennessee Agricultural Extension Service. The report presents data of selected water-quality constituents and properties of water samples collected from 398 domestic wells, located primarily in rural areas. Nitrate concentrations exceeded 10 milligrams per liter in water from 73 of the 398 wells. Fecal coliform and fecal streptococci bacteria were detected in water from 21 and 118 wells, respectively.

Tennessee↗
USGS1988

Water required, water used, and potential water sources for rice irrigation, north coast of Puerto Rico

A 3-yr investigation was conducted to determine the water required and used (both consumed and applied) for irrigation in the rice-growing areas of Vega Baja, Manati, and Arecibo along the north coast. In addition, the investigation evaluated the water resources of each area with regard to the full development of rice farming areas. Based on experiments conducted at selected test farms, water required ranged from 3.13 to 5.25 acre-ft/acre/crop. The amount of water required varies with the wet and dry seasons. Rainfall was capable of supplying from 31 to 70% of the water required for the measured crop cycles. Statistical analyses demonstrated that as much as 95% of rainfall is potentially usable for rice irrigation. The amount of water consumed differed from the quantity required at selected test farms. The difference between the amount of water consumed and that required was due to unaccounted losses or gains, seepage to and from the irrigation and drainage canals, and lateral leakage through levees. Due to poor water-management practices, the amount of water applied to the farms was considerably larger than the sum of the water requirement and the unaccounted losses or gains. Rivers within the rice growing areas constitute the major water supply for rice irrigation. Full development of these areas will require more water than the rivers can supply. Efficient use of rainfall can significantly reduce the water demand from streamflow. The resulting water demand, however, would still be in excess of the amount available from streamflow. Groundwater development in the area is limited because of seawater intrusion in the aquifers underlying the rice-growing areas. Capture of seepage to the aquifers using wells located near streams, artificial recharge, and development of the deep artesian system can provide additional water for rice irrigation.

Puerto Rico↗
USGS1987

Geochemical evolution of waters within the north coast limestone aquifers of Puerto Rico: A conceptualization based on a flow path in the Barceloneta area

Water samples along a groundwater flow path in the Barceloneta area, Puerto Rico, were collected from wells screened in the Montebello Limestone Member of the Cibao Formation (artesian aquifer) and in the overlying Aguada and Aymamon Limestones (water table aquifer). The groundwater chemistry changes as water migrates from recharge areas to downgradient zones in the aquifers. Dissolved magnesium, dissolved sulfate, pH, and carbon-13 isotope generally increase down-gradient. Total inorganic carbon and calcium decrease within the freshwater parts of the aquifer. Mass transfer calculations show that the likely reaction model is carbon dioxide incorporation as water infiltrates through the soil zone, followed by calcite dissolution as water recharges the aquifer. As water moves downgradient within the artesian aquifer, carbon dioxide may degas as a result of calcite precipitation while gypsum and dolomite are dissolved. Within the water table aquifer, continuous recharge of waters rich in carbonic acid maintains the dissolution of the carbonate minerals. Near the coast the mixing of fresh groundwater with saltwater is the primary process affecting water chemistry within the water table aquifer.

Puerto Rico↗