From purpose and scope: The purpose of this investigation is to document the types of aquatic benthic organisms found within the Everglades and to determine the extent to which the chemical and physical character of surface water and bottom materials affect their distribution and community structure.

From abstract: The Hueco Bolson provides a substantial part of the municipal and industrial water supply of the El Paso area of Texas, New Mexico and Mexico. Although the supply of fresh ground water in the bolson is large, about 10.6 million acre-feet (13,070 hm^3) in 1973 in the Texas part of the bolson alone, the supply is being depleted.

Recycling water within the local ground-water system is an effective means to increase quantity and control water temperature of the water supply and to control or avoid environmental pollution. A fish-rearing facility, operated for 15 months, returned water to the local ground-water system through an infiltration pond and recycled 83 percent of its water supply. For each 100 gallons pumped the net stress on the aquifer was equivalent to withdrawing 17 gallons. Despite recycling, nutrient content and temperature of the water supply were acceptable throughout the study period. The rearing-facility nutrient output ranged from 1 to 2 pounds of nitrate-nitrogen per day, but nitrate-nitrogen levels in the water supply remained below 4 mg/1. The water temperature ranged from 7°C to 14°C. Mathematical relations developed show that acceptable nitrate-nitrogen levels and water temperatures nearly optimum for salmonid rearing could be maintained during full-scale hatchery operation.