Developing Life‐Cycle Environmental Response Costs for Leaking Underground Storage Systems at Service Station Sites

Leaking underground storage tank systems at service stations have resulted in tens of thousands of petroleum releases and associated groundwater chemical plumes often extending hundreds of feet off‐site. Technical and engineering approaches to assess and clean up releases from underground tanks, product lines, and dispensers using technologies such as soil vapor extraction, air sparging, biostimulation, and monitored natural attenuation are well understood and widely published throughout the literature. This article summarizes life‐cycle environmental response costs typically encountered using site‐specific cost estimation or metric‐based cost categories considering the overall complexity of site conditions: (1) simple sites where response actions require smaller scale assessments and/or remediation and have limited or no off‐site impacts; (2) average sites where response actions require larger scale assessments and/or remediation typical of petroleum releases; (3) complex sites where response actions require greater on‐site and/or off‐site remediation efforts; and (4) mega sites where petroleum plumes have impacted public or private water supplies or where petroleum vapors have migrated into occupied buildings. Associated cleanup cost estimates rely upon appropriate combinations of individual work elements and the duration of operation, maintenance, and monitoring activities. These cost estimates can be offset by state reimbursement funds, coverage in purchase agreements, and insurance policies. A case study involving a large service station site portfolio illustrates the range of site complexity and life‐cycle environmental response costs. © 2014 Wiley Periodicals, Inc.     

Water quality associated public health risk in Bo, Sierra Leone

Human health depends on reliable access to safe drinking water, but in many developing countries only a limited number of wells and boreholes are available. Many of these water resources are contaminated with biological or chemical pollutants. The goal of this study was to examine water access and quality in urban Bo, Sierra Leone. A health census and community mapping project in one neighborhood in Bo identified the 36 water sources used by the community. A water sample was taken from each water source and tested for a variety of microbiological and physicochemical substances. Only 38.9% of the water sources met World Health Organization (WHO) microbial safety requirements based on fecal coliform levels. Physiochemical analysis indicated that the majority (91.7%) of the water sources met the requirements set by the WHO. In combination, 25% of these water resources met safe drinking water criteria. No variables associated with wells were statistically significant predictors of contamination. This study indicated that fecal contamination is the greatest health risk associated with drinking water. There is a need to raise hygiene awareness and implement inexpensive methods to reduce fecal contamination and improve drinking water safety in Bo, Sierra Leone.     

Sex-biased dispersal in a long-lived polygynous reptile (Crocodylus johnstoni )

We compared natal dispersals of freshwater crocodiles (Crocodylus johnstoni) against the prediction of male dispersal bias for a polygynous mating system. The crocodiles inhabited a linear series of pools and we calculated the net distances from natal pools to recapture locations some 12–18 years later, at maturity. Philopatry was assessed in terms of adult social distances. A female social distance was 0.46 pools and a male social distance was 1.0 pool. By these criteria, both sexes showed low levels of philopatry (7–12%). However, individuals of both sexes dispersed from the natal site long before they were sexually mature. Divergence in dispersal patterns by sex occurred after the maturity threshold, as males dispersed two to three times farther than females. Intrasexual competition by males is resolved by a size-based hierarchy. The displacement of small males from local mating access is a probable cause of the longer dispersals undertaken by males. Competition, rather than inbreeding avoidance, is driving dispersal in this population of freshwater crocodiles. Received: 8 May 1998 / Accepted after revision: 26 June 1998     

Exporting dams: China's hydropower industry goes global

In line with China's "going out" strategy, China's dam industry has in recent years significantly expanded its involvement in overseas markets. The Chinese Export-Import Bank and other Chinese financial institutions, state-owned enterprises, and private firms are now involved in at least 93 major dam projects overseas. The Chinese government sees the new global role played by China's dam industry as a "win-win" situation for China and host countries involved. But evidence from project sites such as the Merowe Dam in Sudan demonstrates that these dams have unrecognized social and environmental costs for host communities. Chinese dam builders have yet to adopt internationally accepted social and environmental standards for large infrastructure development that can assure these costs are adequately taken into account. But the Chinese government is becoming increasingly aware of the challenge and the necessity of promoting environmentally and socially sound investments overseas.     

Gas-phase photolytic production of hydroxyl radicals in an ultraviolet purifier for air and surfaces

We have measured the concentration of hydroxyl radicals (OH) produced in the gas phase by a commercially available purifier for air and surfaces, using the time rate of decay of n-heptane added to an environmental chamber. The hydroxyl generator, an Odorox® BOSS? model, produces the OH through 185-nm photolysis of ambient water vapor. The steady-state concentration of OH produced in the 120 m³ chamber is, with 2σ error bars, (3.25 ± 0.80) × 10⁶ cm^?3. The properties of the hydroxyl generator, in particular the output of the ultraviolet lamps and the air throughput, together with an estimation of the water concentration, were used to predict the amount of OH produced by the device, with no fitted parameters. To relate this calculation to a steady-state concentration, we must estimate the OH loss rate within the chamber owing to reaction with the n-heptane and the 7 ppb of background hydrocarbons that are present. The result is a predicted steady-state concentration in excellent agreement with the measured value. This shows we understand well the processes occurring in the gas phase during operation of this hydroxyl radical purifier.

Implications: Hydroxyl radical air purifiers are used for cleaning both gaseous contaminants, such as volatile organic compounds (VOCs) or hazardous gases, and biological pathogens, both airborne and on surfaces. This is the first chemical kinetic study of such a purifier that creates gas-phase OH by ultraviolet light photolysis of H₂O. It shows that the amount of hydroxyls produced agrees well with nonparameterized calculations using the purifier lamp output and device airflow. These results can be used for designing appropriate remediation strategies.     

Singing performance,frequency matching and courtship success of long-tailed manakins (Chiroxiphia linearis)

We examined the relationship between song performance and courtship success in the lek-mating long-tailed manakin (Chiroxiphia linearis) of Costa Rica. Teams of male manakins form cooperative partnerships consisting of a dominant alpha male and a beta male partner with a variable number of subordinate affiliates. Each alpha and beta partnership performs a joint song virtually in unison, which attracts females to their lek arena. We quantified four aspects of song performance, including synchrony, degree of consistency in the alpha male's singing, degree of consistency in the beta male's singing, and degree of sound frequency matching between partners. When all four variables were included in a discriminant function analysis, average frequency matching alone was useful in discriminating between teams with high rates of visitation by females and those with low visitation rates. Only frequency matching was correlated with the rate at which females visited display lek arenas. We propose that the degree of frequency matching provides an unambiguous ideal against which dual-male courtship performance can be assessed. This aspect of song performance may provide information useful to females in assesing a potential mate's ability to form a cooperative long-term partnership.     

Sources and Distribution of Polychlorinated Terphenyls at a Major US Aeronautics Research Facility

O -deethylase (EROD) activity to a similar degree as PCB Aroclor 1254 and to a greater extent than PCT Aroclor 5460. The presence of high concentrations of PCTs contributed to the facility being included on the National Priorities List. It subsequently became the first US federal facility to sign a Federal Facility Agreement, identifying cleanup responsibilities, prior to formal listing.