Assessing potential risks to wildlife and sportsmen from exposure to dioxin in pulp and paper mill sludge spread on managed woodlands

Potential human and wildlife exposures to TCDD in landspread pulp and paper mill sludge in the State of Maine were evaluated by means of a human health and an ecological risk assessment methodology. The highest historical concentrations of TCDD reported for these sludges do not present a risk to American woodcock, selected as an indicator species for this analysis. Concentrations of TCDD as high as 50 ppt in soil are not likely to produce adverse effects in the embryonic/hatchling stage of the woodcock. This soil concentration of TCDD does not present a significant risk to sportsmen and their families that may consume birds which inhabit these sites.     

The use of carbon and nitrogen isotope ratios to identify landfill leachate contamination: Green Island Landfill, Dunedin, New Zealand

A study was undertaken to determine whether the isotopic ratios of C and N could be used to uniquely identify municipal solid waste landfill leachate as a source of contamination in the Kaikorai Estuary, Dunedin, New Zealand. Leachate samples were taken from the adjacent Green Island Landfill (GILF), and surface water samples were collected over an 8-month period from the stream and estuary, upstream and downstream of the landfill. Samples were analysed for delta(13)C-dissolved inorganic carbon (DIC), delta(15)N-NO(3)(-), delta(15)N-NH(4)(+), and particulate organic matter (POM) delta(13)C and delta(15)N. Plant material collected along the Kaikorai Stream was analysed for POM delta(13)C and delta(15)N. Leachate was found to have a distinct isotopic signature characterised by a highly enriched delta(13)C-DIC (as much as 16.11+/-0.23 per thousand ) and highly enriched delta(15)N-NH(4)(+) (as much as 27.42+/-0.90 per thousand ). Evidence of leachate contamination was found in the isotopic signatures of downstream delta(13)C-DIC, delta(15)N-NH(4)(+), and delta(13)C and delta(15)N of plant material POM. Other potential sources of enriched delta(13)C-DIC and delta(15)N-NH(4)(+) present in the study area, such as estuarine waters and livestock effluent, were eliminated on the basis of their isotopic characteristics.     

Radionuclide applications in laboratory studies of environmental surface reactions

The advantages of using radionuclides for laboratory studies of environmental processes include the wide range of element concentrations that can be studied, the capability to simultaneously study several isotopes in a single experiment, the direct applicability to the behaviour of radioactive waste or fallout, and the ability to study the mechanisms, reversibility and kinetics of environmental reactions under controlled conditions. These attributes are demonstrated using specific examples drawn from case studies in Australia, including radionuclide fallout onto tropical soils, the association of trace metals with harbour sediments and the behaviour of uranium in natural and contaminated systems.     

Cosmogenic 7Be deposition in North Wales: 7Be concentrations in sheep faeces in relation to altitude and precipitation

Beryllium-7 (7Be) is a cosmogenic radionuclide with a half-life of 53.3 days produced mostly in the stratosphere by cosmic ray spallation of nitrogen and oxygen and entering the lower troposphere by atmospheric circulation processes. Most of the nuclide is removed by rainout during precipitation, so given that rainfall generally increases with altitude, it was considered probable that 7Be deposition would also be greater at higher altitudes. The aim of this study was to determine if there is any relationship between 7Be concentrations, altitude and precipitation by measuring 7Be activity within sheep faeces. An area of North Wales and Northwest England was selected for study, extending from the Dee Estuary at sea level to Snowdon at 1065 m. The results obtained showed a significant increase in 7Be activity with increasing altitude and precipitation consistent with predictions based on the existing literature.     

D-Pulegone: A feeding deterrent to deer mice (Peromyscus maniculatus) and prairie voles (Microtus ochrogaster)

Summary D-Pulegone, a monoterpene present in pennyroyålMentha sp. is repellent to a number of vertebrates, decreasing consumption of feed and granular particles. In the present study, several tests were used to determine the reliability of this substance as a feeding deterrent. D-Pulegone (10mM—1M) applied as a coating to apple pieces significantly (P < 0.001) decreased ingestion by deer mice,Peromyscus maniculatus, and prairie voles,Microtus ochrogaster. The deterrent effect of d-pulegone was not diminished following multiple exposures suggesting that this compound may be a promising candidate for use a a general vertebrate repellent. The inhibitory effect of 1M d-pulegone on apple ingestion in voles was abolished when contact was prevented by encasing the stimulus solution in plastic mesh capsules. We conclude that while d-pulegone has repellent properties following direct contact, volatile exposure alone may not be sufficient to elicit avoidance behavior.     

EXAMPLES OF LANDFILL-GENERATED PLUMES IN LOW-RELIEF AREAS,SOUTHEAST FLORIDA1

ABSTRACT: Areas of low topographic relief have low water-table gradients and make the direction of movement of contaminants from land fills in the ground water difficult to predict from regional gradients alone. The landfill, nearby free-flowing ditches or canals, variations in hydraulic conductivity, and the influence of nearby pumping wells can all affect the direction of flow. In low-gradient areas the concepts of “upgradient” and “downgradient” are less useful in planning the location of monitoring wells than in areas of higher relief. Low-relief areas also may be affected by the discharge of mineralized water from deeper aquifers, naturally or through irrigation, which can mask geochemical surveys intended to detect landfill leachate. Examples of effects of low topographic relief are noted in southeast Florida where water-table gradients are 7×10^?-⁴ to 5×10^?-⁴ feet per foot. Water-table mounding beneath the landfill and the drainage effects of nearby ditches and well have created multiple leachate plumes in Stuart where one plume migrated in a direction opposite to the apparent regional gradient. In Coral Springs analysis suggests a bifurcating plume migrating along two narrow zones. In Fort Pierce it was difficult to detect leachate because of mineralized irrigation water and fertilizer runoff from an adjacent citrus grove.     

ALTERNATIVES FOR SALINITY MANAGEMENT IN THE COLORADO RIVER BASIN1

ABSTRACT The Colorado River Basin faces the dilemma of an increasing demand for water while presently struggling with salinity concentrations approaching critical levels for some water uses. Based upon projected development salinity concentrations are predicted to exceed 1200 mg/1 at Imperial Dam by the year 2010. Annual losses to the basin economy associated with increased salinity will exceed $50 million by the year 2010. Although methods of controlling salt discharges are relatively unrefined, certain conclusions, based upon Bayesian statistical methods, can be reached. Five basic alternatives for coping with the problem are presented and evaluated in this paper: (1) do nothing; (2) adopt arbitrary salinity standards; (3) limit development; (4) control salt discharges at a cost equal to the cost of doing nothing, or (5) minimize total costs to the basin. Total costs associated with any given alternative, or the given salinity resulting, are the sum of salinity detriments (cost to users for water of increased salinity plus economic multiplier effects) plus the cost of constructing salt discharge control works. These impacts upon basin economy and Colorado River water quality for each alternative are presented and related to questions of equity which will play a role in arriving at any long-term solution to the Basin's problem.     

ON THE ECONOMIC IMPACT OF LARGE DIVERSIONS OF SNAKE RIVER WATERS1

ABSTRACT. This work evaluates the economic losses due to diversion from the Snake River during the relatively low-flow year May 1928-April 1929. The results determine the losses due to pollution abatement and power generation for several different patterns and volumes of diversion, and the tool of analysis is dynamic programming.     

Crisis Management to Controlled Recovery: The Emergency Planning Response to the Bombing of Manchester City Centre

Fuelled by terrorist attacks on urban areas, emergency planning responses to manmade disasters is a growing area of critical debate within the field of urban management. The response of a major British city--Manchester--to the 1996 bombing of its commercial core, is examined in this paper. It focuses on the transformation of the emergency planning response from dealing with the immediate crisis during the first week, to a stage of controlled recovery that still continues. The response to the devastation caused by the bomb was co-ordinated by the city council, which developed a range of short- and long-term initiatives, but the re-opening of the city centre could not have happened so quickly had the council not worked in collaboration with other key organisations and agencies. Working partnerships were crucial to the immediate response and subsequent recovery, with such capacity for organisational learning built upon existing co-operative arrangements within the city, which had developed over the previous decade.