Characterization and pilot‐scale studies for chemical oxidation remediation of fractured shale

The distribution of volatile organic compounds (VOCs) in fractured shale overlain by thin (< 10 feet) overburden at the Watervliet Arsenal near Albany, New York, was initially determined by sampling water from the fracture network using packer systems in boreholes and also using conventional monitoring wells. Furthermore, short‐term pumping and injection tests were conducted and the boreholes were logged using a variety of geophysical and hydrophysical tools. Tetrachloroethene is the dominant VOC in the groundwater, with lesser concentrations of trichloroethene and degradation products (cis‐1,2‐dichloroethene, trans‐1,2‐dichloroethene, and vinyl chloride). The vertical VOC distributions in the rock matrix were obtained from continuous‐cored holes from which small rock samples, collected at many depths between 18 and 150 feet below ground surface, were analyzed. The rock core VOC concentrations were determined by methanol extraction of crushed rock followed by direct methanol injection onto a gas chromatograph and subsequent estimation of rock porewater VOC concentrations. The rock core data support the concept that diffusion‐driven mass transfer has caused nearly all the VOC mass initially present in the fractures to now reside in the rock matrix, which has a porosity three or four orders of magnitude larger than the bulk fracture porosity. The results of the site characterization indicate that an effective site investigation strategy in fractured shale must include characterization of both the fracture and matrix contaminant distribution. These results also indicate that the most favorable remediation technologies for this fractured shale are those that will destroy VOCs in the rock matrix, particularly contaminants in the sorbed phase, and also destroy the VOC mass in the fractures including both dissolved and immiscible phases. The site characterization resulted in the selection of potassium permanganate for an in situ chemical oxidation pilot study. © 2004 Wiley Periodicals, Inc.     

The response of nematode assemblages to intensive mussel farming in coastal sediments (Southern Brazil)

The impact of mussel farms on the benthic environment was investigated using free-living nematode assemblages as indicators of environmental condition of the Enseada do Brito, a shallow embayment in South Brazil. The studied area is located at the State of Santa Catarina, responsible for 90% of the production of mussel farmed in the country. Samplings were carried out quarterly, from July 2004 to May 2005, below mussel ropes and at control sites located 300 m apart from the longlines. The results suggested that the mussel culture changed ecological functioning of the benthic environment at studied coastal embayment. The intense organic loads due to the biodeposition of the mussel farms, which had been in production for more than 10 years, have turned fine and well-sorted sand bottoms into a muddy deposit with significantly higher total organic content than the control. The number of nematode genera, diversity, dominance and trophic diversity were significantly lower under the mussel farms than at the control sites. The mussel farms biodeposition had also affected the temporal variability of nematode assemblages, which was detected only for samples at the control sites. The low depth and environmental energy, together with the age of the farms, were probably responsible for the observed changes in the nematode assemblages.     

Criticism of the philosophy for development of standards for non-ionizing radiation

The new recommendations of WHO and EC for legislation in Europe and other countries concerning non-ionizing radiation (NIR) health and safety include exposure limits that are very debatable. ICNIRP Guidelines propose exposure limits for electromagnetic fields in the frequency range up to 300 GHz based on short-term exposures and on thermal effects. The new EC proposal for optical and laser safety legislation includes classification of sources of radiation—both lasers and other optical sources, but not requirements for the methodology of classification. On the other hand, many new requirements have been set by the WHO publication “Model Legislation for EMF Protection” concerning the responsibilities in the field of EMF health and safety. Many specialists in the field of developing exposure limits have positions very far away from the proposed of the ICNIRP Guidelines philosophy. The results are different approaches in developing standards and exposure limits, and differences more than 100 times in maximal permissible levels. We, the Bulgarian Program Committee on NIR, try to organize working groups and discuss different philosophy for developing exposure limits for more than 10 years. This paper exposes our position in this area.     

Large emissions of sesquiterpenes and methyl chavicol quantified from branch enclosure measurements

Multiple field studies have suggested chemistry within a forest canopy is poorly understood due to inadequate detection and quantification of reactive biogenic emissions, such as terpenes. To measure emission rates of terpenes at Blodgett Forest, a coniferous forest in the Sierra Nevada mountains of California, we placed enclosures over branches of the dominant species at the site – Ponderosa pine, manzanita, and ceanothus – in the summer of 2005. Zero air, with ambient CO₂ concentrations, flowed through the chamber system and volatile organic compound (VOC) emission measurements were made by proton transfer reaction mass spectrometry (PTR-MS), solid phase microextraction (SPME) on fibers followed by direct injection into a gas chromatograph with an ion trap mass spectrometer (GC-ITMS), and by in situ GC with a flame ionization detector (GC-FID). We show that previously undetected sesquiterpenes and methyl chavicol significantly contribute to the total reactive biogenic emission profile from this field site.     

The network imaginary: coherence and creativity within a multiscalar collaborative effort to reform US fire management

In response to the ongoing crisis in fire management, the US Fire Learning Network (FLN) engages partners in collaborative, landscape-scale ecological fire restoration. The paper contends that the FLN employs technologies, planning guidelines and media to articulate an FLN imaginary that co-ordinates independent efforts to engage in ecological fire restoration work without need of either hierarchal authority or collective social capital. This imaginary may allow the FLN to draw on the creativity and adaptive innovation of collaboration to reform fire management institutions and fire-adapted ecosystems.     

Environmental forensics: the case for professional registration

The origins and purpose of the Council for the Registration of Forensic Practitioners (CRFP) is described, and its emergence as the primary source of assurance of the current professional competence of forensic practitioners is demonstrated. While the main emphasis of CRFP thus far is within the criminal justice system, its approach and principles are equally applicable to civil courts, tribunals, arbitrations and like legal contexts. The case is made for those engaged in environmental forensic work to come within the scope of CRFP with resultant benefits to practitioners, their employers and the public at large.     

In Situ Measurement of Hydrochloric Acid in Rocket Exhaust Clouds Using a Remotely Piloted Aircraft

Abstract

An instrumentation system employing an RPV (remotely piloted vehicle) platform was developed for temporally and spatially resolved air pollution measurements, and was used to measure the evolution of gas-phase HC1 in exhaust clouds from a solid rocket motor firing and fuel pit burns. A thermistor and a sensitive (ppmv-level), rapid-response (<0.1 sec) infrared absorption sensor for HC1 were mounted in a flow channel in the RPV, permitting concentration and temperature measurements to be made in the cloud on a several-meter scale. The RPV system was flown in a series of field tests at Thiokol Corporation’s Elkton, MD division to evaluate the HC1 content of the exhaust products of a new Mg-based fuel formulation. Measurements were made in the clouds from Al-based and Mg-based solid fuel pit burns and a Mg-fueled motor firing over periods of several minutes. Elevated temperatures and HC1 concentrations were found to be temporally correlated with video images of the particulate cloud. Cl originating from the ammonium perchlorate oxidizer appeared in the exhaust as HC1 in each of the tests. Both the macroscopic and local cloud parameters indicate that the Mg-based fuel may provide some reduction in HC1 concentration compared to the standard Al-based fuel.     

Creating conservation strategies with value-focused thinking

Biodiversity and human well-being strategies are only as good as the set of ideas people think about. We evaluated value-focused thinking (VFT), a framework that emphasizes creating objectives and strategies that are responsive to the objectives. We performed a proof-of-concept study of VFT with 6 conservation planning teams at a global conservation organization. We developed a package of materials related to VFT, including meeting–session agendas, a virtual facilitation template, facilitator's guide, and evaluation questionnaires. We used these materials to test whether VFT applied in a group setting resulted in high-quality conservation strategies and participant satisfaction and whether our materials were scalable, meaning that someone newly trained in VFT could facilitate planning meetings that resulted in high-quality strategies and participant satisfaction, as compared with an experienced VFT facilitator. Net response indicated positive compelling, feasible, creative, and representative ratings for the conservation strategies per team. Participants indicated satisfaction overall, although satisfaction was greater for objectives than for strategies. Among the participants with previous conservation planning experience, all were at least as satisfied with their VFT strategies compared with previously developed strategies, and none were less satisfied (p = 0.001). Changes in participant satisfaction were not related to facilitator type (experienced or inexperienced with VFT) (p > 0.10). Some participants had a preconceived sense of shared understanding of important values and interests before participating in the study, which VFT strengthened. Our results highlight the advantages of structuring the development and evaluation of conservation planning frameworks around VFT.