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651.
Policy, Principle, and Practice in Industrial Pollution Control: Views from the Regulatory Interface
There has been much criticism of the system for the control of industrial pollution, but not much is known about the views
of the regulators and the industry. The objective of this study was to explore the attitudes at this regulatory interface
towards the current and proposed regulatory system and make recommendations for improvements. The methodology involved a questionnaire
survey sent to over 700 key personnel. Statistical analysis revealed similarities and significant differences between the
views of industry and the regulator on the effectiveness of the current regime. Weaknesses related to the derivation and enforcement
of standards were identified. The Environmental Quality Standards system was acknowledged to be flawed by both operators and
regulators who agreed it should be improved by the expansion of listed chemicals, the introduction of sediment environmental
quality standards and direct toxicity assessment of effluents. This paper concludes that these measures should be incorporated
into the regulatory system, together with more rigorous enforcement of environmental performance standards including serious
sanctions for non-compliance. In the longer term, a reappraisal of the regulatory system is required in order to establish
an appropriate framework to ensure that environmental policy commitments are implemented. 相似文献
652.
Karl E. Havens Eric G. Flaig R. Thomas James Sergio Lostal Dera Muszick 《Environmental management》1996,20(4):585-593
During 1987–1992, a mandatory program to control phosphorus discharges was implemented at dairy operations located to the north of Lake Okeechobee, Florida, USA. Thirty of 48 dairies participated in this program and implemented best management practices (BMPs), which included the construction of intensive animal waste management systems. Eighteen dairies closed their milkproducing operations under a government-funded buyout program. In this paper, we compare trends in runoff total phosphorus (TP) concentrations among the dairies that remained active and implemented BMPs. A central feature of the dairy waste management system is the high intensity area (HIA), defined as the milking barn and adjacent vegetation-free land, encircled by a drainage ditch and dike. Animal waste from the HIA is diverted into anaerobic lagoons and storage ponds, from which water is periodically removed and used for irrigation of field crops. The impacts of BMP construction on runoff TP concentrations were immediate and, in most cases, dramatic. Average TP concentrations declined significantly (P < 0.001), from 9.0 to 1.2 mg TP liter–1 at dairies in one basin (Lower Kissimmee River), and from 2.6 to 1.0 mg TP liter–1 in another (Taylor Creek/Nubbin Slough). Some sites experienced greater declines in TP than others. To elucidate possible causes for the difference in response, a multivariate statistical model was utilized. Independent variables included soil pH, soil drainage characteristics, spodic horizon depth, and the areas of different BMP components (pasture, HIA, spray fields). The analysis significantly separated dairies with the highest and lowest runoff TP concentrations. Lowest TP occurred at dairies having particular soil characteristic (shallow spodic horizon) and certain BMP features (large HIA and small heard pastures). 相似文献
653.
Rudolph A. Rosen 《Journal of the American Water Resources Association》1982,18(1):147-156
ABSTRACT: Automatic plankton samplers installed at two dams on the Connecticut River Continuously monitored crustacean zooplankton from October 1977 through 1979 and allowed a significant reduction in man-hours involved in an extensive sampling program. Automatic samplers efficiently sampled most species and size classes of crustacean zooplankton in a similar, but not consistently identical manner as a commonly used towed-net plankton sampler. The smallest sized zooplankton were captured more efficiently than the largest. Mesh selection and sampler avoidance exerted different influences on automatic samplers and towed nets. Future use of the samplers and direct comparison of results to results obtained by other methods was supported. 相似文献
654.
ABSTRACT. The need for accurate, independent records of flow on the Columbia River at The Dalles, Oregon, has been met by the installation of an acoustic streamflow-measuring system. This device provides an index of the velocity of flow by measuring the difference in traveltimes of acoustic pulses transmitted through the water in each direction along a diagonal path across the river. The flow of water along the path increases the speed of one signal and retards the speed of the other. The difference in time of travel is related linearly to the water velocity along the path. Installation of the system, which is the first application of an acoustic flowmeter in a large natural channel, was completed in April 1969. It has been in continuous operation since that date. The velocity index and water-surface elevation are used as a two-variable index in the computation of flow. These variables, correlated against current-meter measurements made by use of specialized boat equipment, provide a reliable basis for computations of instantaneous and daily mean discharges. 相似文献
655.
Abdel-Aziz I. Kashef J. C. Smith 《Journal of the American Water Resources Association》1975,11(6):1107-1120
ABSTRACT: In coastal confined aquifers, the extent of the salt-water wedge due to natural ground-water flow can be determined by available methods. If water is pumped by a discharge well, the quality of the water depends upon the rate and duration of pumping as well as the location of the well. A study has been made to find the extent of the progress of salt-water intrusion due to the operation of one discharge well taking into account various conditions of aquifer properties, pump capacities, natural flows, time effects, and well locations. Dimension-less solutions for specific conditions have been obtained by means of a simple computer program. Range of most common conditions is discussed. One of the main findings of this study was that salt water may be pumped out of a well even if it is located in an initially totally fresh-water zone beyond the natural salt/fresh-water interface. 相似文献
656.
Alien T. Hjeimfelt 《Journal of the American Water Resources Association》1986,22(2):267-274
ABSTRACT: A simple nonlinear runoff model was developed and tested for use on field-size agricultural watersheds. A Wooding idealization of the watershed topography was used. Kinematic wave equations were used with an assumed, instead of computed, overland flow, watersurface profile in order to simplify the numerical computations. The approach was used to synthesize runoff hydrographs for an agricultural watershed in Iowa. The accuracy of the synthesized hydro-graphs was judged by comparing the estimated and observed peak discharges and by comparing estimated and observed stages at the measuring weir. The mean errors were 0.01 in/hr and 0.05 ft, respectively. A qualitative comparison was also made with a detailed kinematic wave study. The largest variability occurred during the seedbed period for both models, which was attributed to changes in surface roughness. The roughness was more constant and the results more consistent for the canopy and ground residue periods. 相似文献
657.
Dale A. Devitt David J. Donovan Terry Katzer Michael Johnson 《Journal of the American Water Resources Association》2002,38(6):1735-1751
ABSTRACT: An essential component to the ground water budget for the Las Vegas Valley (LVV) in southern Nevada is discharge from the ground water system. Discharge for the LW has been based on estimates made more than 50 years ago of 35,524,224 m3 per year as evapotranspiration (ET) and 0 m3 per year as subsurface outflow. Newly published values for recharge based on a more robust data set (70,308,360 m3) indicate a large imbalance associated with the earlier discharge estimates, providing the basis for the reevaluation conducted in this study. ET estimates in this study, as opposed to previous studies, were assigned a range in values that included an approach that assigned higher weight to the unique soil, plant, water, and climatic conditions that existed in predevelopment (1905) LW. The earlier discharge estimates also assumed that the basin was hydrologically closed; however, based on our evaluation, a range in yearly discharge by subsurface outflow from 1,480,176 m3 to 19,735,680 m3 could be assigned. Likewise, a range in yearly ET from 20,475,768 m3 to 78,819,372 m3 could be assigned. Based on newly published recharge values, closure can only occur if higher values are assigned to both the subsurface outflow and/or ET components of ground water discharge. We cannot provide a complete water balance closure with our ground water discharge estimate of 64,140,960 m3. However our reevaluation gives support to the higher recharge estimates and provides the rationale for future studies to be conducted based on a more rigorous scientific assessment. 相似文献
658.
659.
660.
Relationship between rainfall and spring discharge study is important to understand hydrological behaviour of springs and water resources management. In the Himalayan mountains springs are the freshwater sources for household consumption. We studied six springs of different recharge area characteristics in two micro-watersheds in western Himalayan mountains in India. Based on the recharge area geology these springs were divided into fracture/joint (FR/JT) and fracture/joint/colluvium (FR/JT/COLL). We found a strong positive relationship between rainfall and spring discharge. Peak spring discharge coincided with peak rainfall in two FR/JT/COLL springs, which was delayed by about one month in FR/JT springs. Mean annual discharge was about two times greater for FR/JT/COLL springs than the FR/JT springs (6.47 vs. 3.94 liter per minute). But spring discharge per 1000 L of rainfall in spring recharge area for FR/JT springs was about 2.3 times greater than the FR/JT/COLL springs (49 vs. 21 liter per minute). In the FR/JT springs, rainfall in spring recharge area and spring discharge were weakly related (r=0.174), while they were strongly related in FR/JT/COLL springs (r=0.595). In the former category of springs decline in discharge was gradual, while it was rapid in the latter category of springs. Therefore, with regard to sustained supply of water for household consumption FR/JT springs can be considered more suitable. Land use and land cover such as moderately grazed pasture, abandoned agricultural terraces and few trees but dense growth of bushes and oak forest in the spring recharge area were found conducive for spring discharge and may be promoted for long-term water resource conservation in this region. 相似文献