Minimizing contamination hazards to waterbirds using agricultural drainage evaporation ponds

In much of the San Joaquin Valley, California, USA, inadequate drainage of applied irrigation water and accumulating salts in the soil have necessitated the installation of subsurface tile drainage systems to preserve crop productivity. At present, these subsurface drainage waters are disposed of by means of evaporation ponds or discharges into the San Joaquin River. Unfortunately, most of these agricultural drainage waters contain high concentrations of salts and naturally occurring trace elements, such as selenium, and recent evidence indicates that substantial numbers of waterbirds are exposed to contamination by selenium in the evaporation ponds. In order to avoid, minimize, or mitigate the adverse impacts on wildlife using the ponds, alternative pond management methods must be identified and evaluated for implementation. A number of methods have the potential to be cost-effective in significantly reducing the contamination hazard to birds using agricultural evaporation ponds. Twenty general methods were evaluated in this study, and four methods are recommended for implementation: remove levee vegetation, remove windbreaks, deepen the ponds, and haze birds. A number of other methods are recommended for further consideration because they appear to have good prospects for reducing the contamination hazard: steepen interior levee slopes, apply herbicides and insecticides, place netting on pond shorelines, and provide freshwater habitat adjacent to evaporation ponds. It may be necessary to use a combination of methods to effectively control selenium contamination of aquatic birds because it is unlikely that a single affordable pond management method will be able to entirely eliminate the contamination hazard.     

Continuous improvement through environmental auditing

Environmental auditing evolved as a means of providing assurance to top management that its health, safety, and environmental responsibilities were being adequately discharged and that no significant noncompliances existed. The author takes an in-depth look at the HSE audit program developed at Allied-Signal to permit continuous improvement of environmental management systems.     

HICKORY CREEK DRY RESERVOIR: A COMPRAOMISE DESIGN FOR BOTH FLOOD CONTROL AND NATURAL AREA PROTECTION1

Abstract: The proposed Hickory and Spring Creeks Flood Control and Recreation Project of the Illinois State Division of Water Resources and the Will County Forest Preserve District is desinged to provide flood control for Joliet, Illinos, and areas of the watershed to the east of the city and to provide open-space recreational land upstream from the Hickory Breek Dry Reservoir embankement. A viable forest ecosytem in the reservoir flood pool following construction is of major importance to the project. Factors of the environment influencing tree distribution and flood tolerance and a process for determining the best operational design to provide both flood control and the maintenance of a natural streamside forest ecosystem are described.     

Taming B.C. Hydro: Site C and the implementation of the B.C. Utilities Commission Act

Public policy making in resources management is greatly influenced by the institutional arrangements that arise out of the legal powers, administrative structures, and financial provisions of the decision system. In British Columbia, the institutional arrangements for energy planning in the province have been greatly altered by the passage of the Utilities Commission Act in 1980. This act redefines the policy implementation process for energy in British Columbia and provides for the regulation of the province's power utility, B.C. Hydro. This is the first time that the hitherto autonomous utility has been subject to regulation and the Utilities Commission Act represents a major reform in the institutional arrangements for energy planning in the province. The article evaluates the effectiveness of the 1980 B.C. Utilities Commission Act and assesses the impact of the legislation upon the institutional arrangements for energy planning in the province. Data for the article were derived from written sources and a series of personal interviews with key participants involved with energy planning in B.C.It is shown that the act represented a major departure in the management of energy resources in B.C. Moreover the implementation of the act's provisions, particularly in regard to B.C. Hydro, had a dramatic impact on the development of new energy projects in the province. It is suggested that while the political and economic climate during the period also favored restraint, the major influence on taming the utility was passage of the Utilities Commission Act. The article concludes by exploring the implications of policy changes that have occurred as a consequence of the act's impact on B.C. Hydro.     

DEVELOPING AND ASSESSING A MODEL OF RESIDENTIAL WATER CONSERVATION1

ABSTRACT: Relevant literature was reviewed from which a model of residential water conservation was developed. Four residential conservation program interventions were posited: 1) public education, 2) pricing variables, 3) water use restrictions, and 4) building code requirements. Four exogenous variables affecting residential water use were also posited: 1) temperature, 2) rainfall, 3) household income, and 4) household size. The impacts of these eight variables on residential per capita daily use were assessed by cross sectional and time series analysis. Study results generally supported the porposed model, with less consistent support obtained for pricing variables and conservation beliefs. The paper concludes with the hypothesis that an inclining block rate structure coupled with an informational program designed to inform consumers of their consumption under each block will have a synergistic impact.     

Mortality, growth, swimming activity and gill morphology of brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) exposed to low pH with and without aluminum

Measurements were made of mortality, growth, swimming activity, and gill morphology of young-of-the-year brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar), exposed for 30 days to pH 5.6 +/- 0.5 (mean +/- 1 standard deviation) with and without addition of 107 +/- 57 microg liter(-1) exchangeable (labile monomeric) aluminum. The experiment was conducted in artificial stream channels adjacent to a natural stream and subject to daily and seasonal changes in temperature, light, and chemical conditions. There were no differences in survival or growth for brook trout in any treatment; Atlantic salmon survival and growth were significantly decreased in the acid + Al treatment. Scanning electron microscopy showed no damage to gills of either species in the acid treatments, but the acid + Al treatment caused slight swelling of brook trout gills near the filament tips and significant swelling and fusion of secondary lamellae of Atlantic salmon gills. The acid treatment increased swimming activity in brook trout, but both the acid and acid + Al treatments reduced activity in Atlantic salmon.     

Tetrachlorodibenzo-p-dioxins and tetrachlorodibenzofurans in Atlantic coast striped bass and in selected Hudson River fish,waterfowl and sediments

In striped bass samples from the lower Hudson River and its estuary 2,3,7,8-tetrachlorodibenzo-$\text{p}$-dioxin (2,3,7,8-TCDD) was found at concentrations from 16 to 120 pg/g (ppt). Striped bass from two other locations (Rhode Island coastal waters and Chesapeake Bay, Maryland) had <5 ppt, 2,3,7,8-TCDD. The contaminant, 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF), was found in striped bass from all three locations with concentrations varying from 6 ppt in Chesapeake Bay to 78 ppt in the Hudson River. Results from a limited number of non-migratory fish (carp and goldfish) and sediments suggest that the upper Hudson River is not a source for 2,3,7,8-TCDD/2,3,7,8-TCDF contamination of striped bass.     

Assessment of municipal waste compost as a daily cover material for odour control at landfill sites

The ability of municipal waste compost as a daily cover material to reduce the odorous emissions associated with landfill surfaces was investigated. Trials were carried out using landfill gas, a certified sulphurous gas mix and ambient air as a control. Odorous gas was passed through portable test column filled with compost at different densities (590 kg/m3 and 740 kg/m3). Gas samples were taken from the inlet, outlet and at varying column depths and examined using a combination of sensory analysis (olfactometry) and a novel analytical method (Transportable Selected Ion Flow Tube--TSIFT). Results for the trials using landfill gas showed a 69% odour reduction (OU/m3) through the column for compost with a bulk density of 590 kg/m3, and a reduction of 97% using compost with a bulk density of 740 kg/m3. TSIFT analysis showed an overall decrease in the concentration of terpenes, and sulphurous compounds in the outlet gas from the column for both bulk densities. No significant trend could be identified for the concentrations at different depths within the column. Results show the ability of compost to reduce landfill odours under differing conditions. The inconclusive data provided by TSIFT analysis may be due to the analysis of compounds that are not contributing to odour, and thus highlights the potential for synergetic effects and the importance of sensory measurement when examining odorous emissions.     

Volatilization rates of intermediate and low volatility chemicals from water

This paper reports laboratory methods for measuring the gas and liquid phase mass transfer coefficients and volatilization rate constants of intermediate and low volatility compounds and proposes a method for calculating the volatilization rate constants of these types of compounds in the environment.