137Cs and 40K in the terrestrial vegetation of the Yenisey Estuary: landscape, soil and plant relationships

Plant species, forming important components of Arctic food chains and of interest from a monitoring perspective, were studied at 36 plots representing flood plain and terrace landscapes of the Yenisey River and Estuary from its upper delta to the gulf. (137)Cs contamination densities at the plots varied from 0.35kBq/m(2) (central delta, sandy riverside plot) to 88kBq/m(2) (the upper delta plot) indicating both global and regional sources of anthropogenic pollution. Cs-137 levels in plants were within the range expected from global fallout inputs and varied from 31 to 140Bq/kg d.w. increasing in dominant groups in the order: grasses相似文献   

Comparison of the particle size distribution of heavy-duty diesel exhaust using a dilution tailpipe sampler and an in-plume sampler during on-road operation

Originally constructed to develop gaseous emission factors for heavy-duty diesel trucks, the U.S. Environmental Protection Agency's (EPA) On-Road Diesel Emissions Characterization Facility has been modified to incorporate particle measurement instrumentation. An electrical low-pressure impactor designed to continuously measure and record size distribution data was used to monitor the particle size distribution of heavy-duty diesel truck exhaust. For this study, which involved a high-mileage (900,000 mi) truck running at full load, samples were collected by two different methods. One sample was obtained directly from the exhaust stack using an adaptation of the University of Minnesota's air-ejector-based mini-dilution sampler. The second sample was pulled from the plume just above the enclosed trailer, at a point approximately 11 m from the exhaust discharge. Typical dilution ratios of about 300:1 were obtained for both the dilution and plume sampling systems. Hundreds of particle size distributions were obtained at each sampling location. These were compared both selectively and cumulatively to evaluate the performance of the dilution system in simulating real-world exhaust plumes. The data show that, in its current residence-time configuration, the dilution system imposes a statistically significant bias toward smaller particles, with substantially more nanoparticles being collected than from the plume sample.     

Planning,Designing, Operating,and Regulating a Geologic Sequestration Repository as an Underground Landfill—A Review

ABSTRACT

Geologic sequestration appears to be a technically feasible method of storing carbon dioxide in underground aquifers in order to lower greenhouse gas emissions into the atmosphere. The overall feasibility of geologic sequestration is still in question and as such, has been the focus of intense research over the past decade. Researchers have looked to the oil/gas industry and water well industry for lessons learned and technical knowledge, however, a better industry to emulate may well be the waste industry. Viewing geologic sequestration repositories as underground landfills has a great many benefits. First, there is a plethora of existing research and investigations that are directly analogous to geologic sequestration projects. Second, the regulatory framework is rather mature and can be easily adapted to serve geologic sequestration. This paper conducts an extensive literature search of the environmental, waste, and geologic sequestration literature to ascertain planning, design, and operational methodologies, lessons learned, and concepts that are directly useful for geologic sequestration to improve the technical and regulatory framework. Lastly, the paper uses a hypothetical underground landfill geologic sequestration site (ULGSS) in Florida, USA to discuss some of the findings and implications from the literature. It is concluded that there are a number of literature findings from the waste and environmental arena that should be adapted for geologic sequestration.

IMPLICATIONS Geologic sequestration is a promising solution for greenhouse gas control. This work supports that notion but suggests further improvements to the technical and regulatory framework based upon an extensive review of the waste management and environmental literature. The improvements include suggestions in the areas of permitting, site selection, operations, cost accounting, and special waste handling. Some of these improvements are discussed using a hypothetical project site in Florida, USA.     

Quality assurance and quality control data validation procedures used for the Love Canal and Dallas lead soil monitoring programs

Public awareness of soils contamination has increased in recent years due in part to the notoriety associated with the indiscriminate release, packaging, transporting and disposal of hazardous materials. In 1980, and again in 1982, the U.S. Environmental Protection Agency (EPA) was responsible for designing, implementing and conducting environmental monitoring programs at Love Canal in Niagara Falls, New York, and in Dallas, Texas, that dealt with suspected contaminated soils. Both of these monitoring programs were conducted over a relatively short time with the collection and analysis of over 4000 soil samples. The methods employed by the Environmental Protection Agency for providing soil data that was scientifically valid and of defensible quality for each of these monitoring programs are presented. Also, methods for identifying data bias, its precision and its uncertainty are identified.     

Redesigning the FDMT Food Chain Transfer Model: Now Probabilistically Enabled and Fully Flexible

Environmental Modeling & Assessment - In Europe, the two main nuclear accident response decision support systems in use are ARGOS and JRODOS, both of which make use of the FDMT (Food Chain and...