Environmental impact assessment in the Philippines: 1977–1985

During 1977 a Philippine environmental impact statement (EIS) system was established and the National Environmental Protection Council (NEPC) was formed to develop environmental policy. Several months after its creation, NEPC was given responsibility to certify that proposed projects met EIS system regulations. With few exceptions, this requirement to gain NEPC's approval was not taken seriously by agencies. The poor record of agency compliance with the EIS system is explained by the absence of ‘controls’ to force thorough assessments. Judicial controls are absent. Procedural and evaluative controls are in place, but NEPC has neither the budget nor the political power to enforce them. Although the national EIS system is ineffective, agencies sometimes conduct informal, ad hoc environmental assessments in response to instrumental controls exercised by international funding organizations, professional controls exerted by planners, and public controls brought about by individuals and groups who would be adversely affected by projects.     

CONSIDERATIONS IN CHOOSING THE APPROPRIATE MIX OF URBAN AND AGRICULTURAL NONPOINT POLLUTION CONTROL1

ABSTRACT: In developing strategies for nonpoint pollution control in designated 208 areas, one of the issues facing planners is the relative emphasis which should be placed upon urban versus agricultural non-point control. Five criteria which should be considered in designing an appropriate BMP strategy mix are discussed: 1) BMP cost effectiveness; 2) information and administrative cost; 3) flexibility, which relates to the cost of reversibility given substantial uncertainties; 4) associated effects, both direct and indirect; and 5) acceptability to local jurisdictions and groups. Whatever an evaluation on the basis of the first four criteria may suggest, acceptance of agricultural BMPs will be difficult to achieve, thus favoring urban oriented strategies, unless local revenue sources are developed to offer payments to farmers for BMP adoption.     

Dominance of the odometer over serial landmark learning in honeybee navigation

Honeybees use their visual flow field to measure flight distance. It has been suggested that the experience of serial landmarks encountered on the flight toward a feeding place contributes to distance estimation. Here, we address this question by tracing the flight paths of individual bees with a harmonic radar system. Bees were trained along an array of three landmarks (tents), and the distance between these landmarks was either increased or decreased under two test conditions. We find that absolute distance estimation dominates the search for the feeding place, but serial position effects are also found. In the latter case, bees search only or additionally at locations determined by serial experience of the landmarks.     

Impact of ozone assisted ultrasonication pre-treatment on anaerobic digestibility of sewage sludge

Impact of ultrasonication(ULS) and ultrasonication–ozonation(ULS-Ozone) pre-treatment on the anaerobic digestibility of sewage sludge was investigated with semi-continuous anaerobic reactors at solid retention time(SRT) of 10 and 20 days. The control, ULS and ULS-Ozone reactors produced 256, 309 and 348 m L biogas/g CODfedand the volatile solid(VS) removals were 35.6%, 38.3% and 42.1%, respectively at SRT of 10 days. At SRT of20 days, the biogas yields reached 313, 337 and 393 m L biogas/g CODfedand the VS removal rates were 37.3%, 40.9% and 45.3% in the control, ULS and ULS-Ozone reactors, respectively.ULS-Ozone pre-treatment increased the residual organic amount in the digested sludge.These soluble residual organics were found to contain macromolecules with molecular weights(MW) larger than 500 k Da and smaller polymeric products with MW around 19.4and 7.7 k Da. These compounds were further characterized to be humic acid-like substances with fluorescent spectroscopy analysis.     

In-situ application of colloidal activated carbon for PFAS-contaminated soil and groundwater: A Swedish case study

Soil and groundwater contamination by per- and polyfluoroalkyl substances (PFAS) has been a significant concern to human health and environmental quality. Remediation of contaminated sites is crucial to prevent plume expansion but can prove challenging due to the persistent nature of PFAS combined with their high aqueous mobility. In this case study, we investigated the potential of colloidal activated carbon (CAC) for soil stabilization at the pilot scale, aiming to entrap PFAS and prevent their leaching from soil into groundwater. Monitoring of the site revealed the presence of two potential sources of PFAS contamination at concentrations up to 23 μg L⁻¹ for ∑₁₁PFAS in groundwater. After CAC application, initial results indicated a 76% reduction of ∑₁₁PFAS and high removal rates for long-chain PFAS, such as perfluorooctane sulfonic acid and perfluorooctanoic acid. A spike in concentrations was noticed 6 months after injection of CAC, showing a rebound of the plume and a reduction of treatment effectiveness. Based on long-term monitoring data, the treatment effectiveness for ∑₁₁PFAS dropped to 52%. The rebound of concentrations was attributed to the plume bypass of the barrier due to the presence of high conductivity zones, which likely occurred because of seasonal changes in groundwater flow directions or the CAC application at the site. This demonstrates the need for a detailed and accurate hydrogeological understanding of contaminated sites before designing and applying stabilization techniques, especially at sites with high geologic and hydrologic complexity. The results herein can serve as a guideline for treating similar sites and help avoid potential pitfalls of remedial efforts.