Spill Conditions Research Articles

МЕЗОМАСШТАБНАЯ УСТАНОВКА ДЛЯ ОЦЕНКИ ЭФФЕКТИВНОСТИ ДИСПЕРГЕНТОВ, ПРИМЕНЯЕМЫХ ПРИ ЛИКВИДАЦИИ АВАРИЙНЫХ РАЗЛИВОВ НЕФТИ

Spillage of oil or petroleum products into marine and inland waters has severe environmental consequences for the ecosystem of the region where the spill occurred. To minimize the consequences of such accidents, various methods of elimination can be used: mechanical, physico-chemical, thermal, biological. The expediency of using a particular method is determined based on the liquidation plan, and is individual for each specific spill. The right combination of methods is a key factor that guarantees complete elimination of the undesirable consequences of an accident. This article discusses the method of chemical dispersion as one of the ways to eliminate accidental oil spills in marine areas. The question of the complexity of evaluating the effectiveness of dispersing compositions is raised. An argumentation of the disadvantages of existing methods of analysis is given. As an example of solving the described problem, an example of using a mesoscale installation simulating oil spill conditions is given. Its main technical characteristics and method of operation are published. The components of the installation and auxiliary components are also described in detail. As an example of operation at the installation, the results of an experiment to evaluate the effectiveness of two dispersing compositions depending on the thickness of the oil pollution film, which cannot be obtained using laboratory testing methods, are presented. Hence, it can be concluded that tests on a mesoscale installation can be the main tool in developing an oil spill response plan. In addition, they can be used to evaluate the dispersing properties of formulations and individual surfactants under conditions as close as possible to real ones.

Limited impact of weathered residues from the Deepwater Horizon oil spill on the gut-microbiome and foraging behavior of sheepshead minnows (Cyprinodon variegatus)

ABSTRACT The Deepwater Horizon disaster of April 2010 was the largest oil spill in U.S. history and exerted catastrophic effects on several ecologically important fish species in the Gulf of Mexico (GoM). Within fish, the microbiome plays a key symbiotic role in maintaining host health and aids in acquiring nutrients, supporting immune function, and modulating behavior. The aim of this study was to examine if exposure to weathered oil might produce significant shifts in fish gut-associated microbial communities as determined from taxa and genes known for hydrocarbon degradation, and whether foraging behavior was affected. The gut microbiome (16S rRNA and shotgun metagenomics) of sheepshead minnow (Cyprinodon variegatus) was characterized after fish were exposed to oil in High Energy Water Accommodated Fractions (HEWAF; tPAH = 81.1 ± 12.4 µg/L) for 7 days. A foraging behavioral assay was used to determine feeding efficiency before and after oil exposure. The fish gut microbiome was not significantly altered in alpha or beta diversity. None of the most abundant taxa produced any significant shifts as a result of oil exposure, with only rare taxa showing significant shifts in abundance between treatments. However, several bioindicator taxa known for hydrocarbon degradation were detected in the oil treatment, primarily Sphingomonas and Acinetobacter. Notably, the genus Stenotrophomonas was detected in high abundance in 16S data, which previously was not described as a core member of fish gut microbiomes. Data also demonstrated that behavior was not significantly affected by oil exposure. Potential low bioavailability of the oil may have been a factor in our observation of minor shifts in taxa and no behavioral effects. This study lays a foundation for understanding the microbiome of captive sheepshead minnows and indicates the need for further research to elucidate the responses of the fish gut-microbiome under oil spill conditions.

The influence of ocean acidification and warming on responses of Scylla serrata to oil pollution: An integrated biomarker approach.

Anthropogenic activities primarily combustion of fossil fuel is the prime cause behind the increased concentration of CO2 into the atmosphere. As a consequence, marine environments are anticipated to experience shift towards lower pH and elevated temperatures. Moreover, since the industrial revolution the growing demand for petroleum-based products has been mounting up worldwide leading to severe oil pollution. Sundarbans estuarine system (SES) is experiencing ocean warming, acidification as well as oil pollution from the last couple of decades. Scylla serrata is one of the most commercially significant species for aquaculture in coastal areas of Sundarbans. Thus, the prime objective of this study is to delineate whether exposure under ocean warming and acidification exacerbates effect of oil spill on oxidative stress of an estuarine crab S. serrata. Animals were separately exposed under current and projected climate change scenario for 30days. After this half animals of each treatment were exposed to oil spill conditions for 24h. Oxidative stress status superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), lipid peroxidation (LPO level) and DNA damage (Comet assay) were measured. Augmented antioxidant and detoxification enzyme activity was noted except for SOD but failed to counteract LPO and DNA damage. The present results clearly highlighted the detrimental combined effect of OWA and pollution on oxidative stress status of crabs that might potentially reduce its population and affect the coastal aquaculture in impending years.

Improving the design and conduct of aquatic toxicity studies with oils based on 20 years of CROSERF experience

Laboratory toxicity testing is a key tool used in oil spill science, spill effects assessment, and mitigation strategy decisions to minimize environmental impacts. A major consideration in oil toxicity testing is how to replicate real-world spill conditions, oil types, weathering states, receptor organisms, and modifying environmental factors under laboratory conditions. Oils and petroleum-derived products are comprised of thousands of compounds with different physicochemical and toxicological properties, and this leads to challenges in conducting and interpreting oil toxicity studies. Experimental methods used to mix oils with aqueous test media have been shown to influence the aqueous-phase hydrocarbon composition and concentrations, hydrocarbon phase distribution (i.e., dissolved phase versus in oil droplets), and the stability of oil:water solutions which, in turn, influence the bioavailability and toxicity of the oil containing media. Studies have shown that differences in experimental methods can lead to divergent test results. Therefore, it is imperative to standardize the methods used to prepare oil:water solutions in order to improve the realism and comparability of laboratory tests. The CROSERF methodology, originally published in 2005, was developed as a standardized method to prepare oil:water solutions for testing and evaluating dispersants and dispersed oil. However, it was found equally applicable for use in testing oil-derived petroleum substances. The goals of the current effort were to: (1) build upon two decades of experience to update existing CROSERF guidance for conducting aquatic toxicity tests and (2) to improve the design of laboratory toxicity studies for use in hazard evaluation and development of quantitative effects models that can then be applied in spill assessment. Key experimental design considerations discussed include species selection (standard vs field collected), test substance (single compound vs whole oil), exposure regime (static vs flow-through) and duration, exposure metrics, toxicity endpoints, and quality assurance and control.

Novel Insights into the Influence of Soil Microstructure Characteristics on the Migration and Residue of Light Non-Aqueous Phase Liquid.

Understanding the influence of soil microstructure on light non-aqueous phase liquids (LNAPLs) behavior is critical for predicting the formation of residual LNAPLs under spill condition. However, the roles of soil particle and pore on LNAPLs migration and residue remains unclear. Here, the experiment simulated an LNAPLs (diesel) spill that was performed in fourteen types of soils, and the key factors affecting diesel behavior are revealed. There were significant differences between fourteen types of soils, with regard to the soil particle, soil pore, and diesel migration and residue. After 72 h of leakage, the migration distance of diesel ranged from 3.42 cm to 8.82 cm in the soils. Except for sandy soil, diesel was mainly distributed in the 0−3 cm soil layer, and the residual amounts were 7.85−26.66 g/kg. It was further confirmed from microstructure that the consistency of soil particle and volume of soil macropores (0.05−7.5 μm) are important for diesel residue in the 0−1 cm soil layer and migration distance. The large soil particles corresponding to 90% of volume fraction and volume of soil mesopores (<0.05 μm) are key factors affecting diesel residue in the 1−3 cm soil layer. The result helps to further comprehend the formation mechanism of residual LNAPLs in the soil.

Barefoot Slip Risk in Indian Bathrooms: A Pilot Study

Barefoot slips and falls are commonly reported in bathrooms in Indian households and apartments. Due to lack of awareness on how to prevent such incidents, they are often neglected, and may lead to recurrent and severe traumatic injuries. To date, there is no way to assess the barefoot slip risk of the bathroom flooring tiles under realistic contaminated conditions such as with water and shampoo. In this work, a novel human heel surrogate was developed for barefoot slip testing, to address this gap. This surrogate was tuned to precisely mimic the frictional and biomechanical properties of the human heel, through three-dimensional (3D) scanning and printing. A mechanical slip testing device was employed with the heel surrogate to test 15 different bathroom floorings in residential apartments in dry and slippery conditions (i.e., wet and with shampoo spill). The barefoot available coefficient of friction (ACOF) was determined for the different floor conditions and tested for repeatability with two modeled heel surrogate samples. Also, the correlation of ACOF with surface roughness and between floorings was studied, across contaminant conditions. High repeatability (r 2 > 0.92) was confirmed in the dry condition, and the ACOF values decreased significantly when going from dry to wet and wet to shampoo spill conditions. The correlation of ACOF with surface roughness was found to be high (r 2 = 0.72), medium (r 2 = 0.62), and low (r 2 = 0.38) for the dry, wet, and shampoo spill conditions, respectively. Across contaminant conditions, several tiles exhibited high correlations in ACOF due to shampoo spills, indicating generalizability of barefoot slip risk. The findings of low barefoot frictional resistance on Indian bathroom floorings in wet and shampoo spill conditions, lack of correlations with surface roughness, and high generalizability of slip risk across floorings in the shampoo spill condition have not been reported to date, and shed light on the significant barefoot slip risks.

Effect of Sea Temperature on Crude Oil Spill Condition – Simulator Pisces II

Effect of Sea Temperature on Crude Oil Spill Condition – Simulator Pisces II

Experimental study on vertical spill fire characteristics of transformer oil under continuous spill condition

A vertical spill fire is one of the typical phenomena in fire scenes, which usually occurs with liquid fuel usage and storage and may pose a threat to process safety. In this study, a number of transformer oil continuous spill fire experiments were carried out on a steel experimental setup, in order to obtain the vertical spill fire characteristics of transformer oil or fuels that have similar properties as transformer oil. The flame shape, temperature and radiation data in the process of flame propagation were recorded. According to the change of the burning area, the formation and development process of a vertical spill fire can be divided into four stages. The relationship between burning area and fuel leakage rate in the quasi-stable combustion stage is analyzed and a prediction model for the burning area of a transformer oil vertical spill fire is established. The radiation model of a transformer oil vertical spill fire is established as a function of leakage rate. Based on heat transfer analysis, a mass burning rate model is derived and verified by experimental data.

Atmospheric particulate fractions from Nigerian crude oil spillage

Laboratory simulations of the spill behaviors of three different Nigerian crude oil samples over three media (fresh water, sea water and soil) were carried out with a view to determining the effect of crude oil spillage on emission of fine (PM2.5) and inhalable particulates fractions (PM10). The spillage experiments were carried out in an environmental test box fitted with equipment to regulate the micro climatic conditions (temperature and Relative humidity). The maximum concentrations of PM2.5 were 711, 689 and 680 µgm−3 while those of PM10 were 972, 946 and 940 µgm−3 for sample A, B and C respectively. These peak concentrations were obtained for spill conditions corresponding to fresh water at 45 °C and 49% relative humidity. The least concentrations of PM2.5 and PM10 emitted across all samples were 63 µgm−3 and 256 µgm−3 respectively and these corresponded to spillage over sea water at 15 °C and 80% relative humidity. These concentrations clearly exceeded the short time averaging period (24 h) standards set for PM2.5 and PM10 by the United States Environmental Protection Agency. Incessant crude oil spillages in the Nigerian oil fields are therefore predicted to cause degradation of air quality within a short duration from the spill.

The simulation of weathering processes in three different types of oil

Pipeline leaks, wells damage, and water transportation accidents are some of the causes of oil spills at sea. This spill causes seawater pollution and disturbs the equilibrium of marine life. Oil spills will spread and move with the influence of currents and sea wind. Spilled oil undergoes several physical and chemical processes, including spreading, evaporation, emulsification, dissolution, and dispersion. This process results in changes in oil density, volume, and viscosity. It is important to be aware of changes in oil spill conditions because it relates to clean up efforts of oil spills at sea. This research presents some mathematical models of the oil weathering processes which include physical and chemical processes. Then a numerical simulation is performed using a finite difference method to see the changes that occur in three types of oil: heavy, medium and light oil. Simulation results show that the three types of oil have a relatively similar tendency to spread. The highest rate of evaporation and emulsion water content is shown by light oil. This resulted in higher volume and viscosity. Therefore, the process of cleaning up will require greater effort for light oil spills.

The effects of run‐of‐river dam spill on Columbia River microplankton

AbstractDams, increasingly common in riverine systems worldwide, are particularly prevalent on the Columbia River (CR) in the United States. Hydroelectric projects, including both storage and run‐of‐river (i.e., minimal storage) structures, on the mainstem CR highly manage water flow, often by releasing water over (rather than through) dams as “spill.” To test the effects of run‐of‐river dam spill on microplankton abundance and composition, we sampled above and below two dams in the lower CR before and during spill conditions in spring 2016 and during and after spill conditions in late summer 2007. We tested the effects of location (i.e., above vs. below dams), spill condition (i.e., before, during, and after spill), and their interaction on microplankton abundance. Generally, diatoms were most abundant during springtime, whereas cyanobacteria were most abundant in late summer. Most taxa were not significantly different in abundance above and below dams, regardless of spill status; although cyanobacteria abundance was marginally higher below dams in summer 2007 (p = .04). Abundances of all taxa were significantly different between pre‐spill and spill periods in spring 2016, whereas only diatom and flagellate abundances were significantly different between spill and post‐spill periods in summer 2007. We conclude that spill conditions may influence microplankton abundance, but are not likely to affect microplankton communities on either side of run‐of‐river dams on the CR. This is important information for dam managers concerned about ecosystem impacts of spill.

Ecological response of nitrification to oil spills and its impact on the nitrogen cycle.

Marine oil spills are catastrophic events that cause massive damage to ecosystems at all trophic levels. While most of the research has focused on carbon-degrading microorganisms, the potential impacts of hydrocarbons on microbes responsible for nitrification have received far less attention. Nitrifiers are sensitive to hydrocarbon toxicity: ammonia-oxidizing bacteria and archaea being 100 and 1000 times more sensitive than typical heterotrophs respectively. Field studies have demonstrated the response of nitrifiers to hydrocarbons is highly variable and the loss of nitrification activity in coastal ecosystems can be restored within 1-2 years, which is much shorter than the typical recovery time of whole ecosystems (e.g., up to 20 years). Since the denitrification process is mainly driven by heterotrophs, which are more resistant to hydrocarbon toxicity than nitrifiers, the inhibition of nitrification may slow down the nitrogen turnover and increase ammonia availability, which supports the growth of oil-degrading heterotrophs and possibly various phototrophs. A better understanding of the ecological response of nitrification is paramount in predicting impacts of oil spills on the nitrogen cycle under oil spill conditions, and in improving current bioremediation practices.

Behavior of Marine Bacteria in Clean Environment and Oil Spill Conditions.

Alcanivorax borkumensis is a bacterial community that dominates hydrocarbon-degrading communities around many oil spills. The physicochemical conditions that prompt bacterial binding to oil/water interfaces are not well understood. To provide key insights into this process, A. borkumensis cells were cultured either in a clean environment condition (dissolved organic carbon) or in an oil spill condition (hexadecane as the sole energy source). The ability of these bacteria to bind to the oil/water interface was monitored through interfacial tension measurements, bacterial cell hydrophobicity, and fluorescence microscopy. Our experiments show that A. borkumensis cells cultured in clean environment conditions remain hydrophilic and do not show significant transport or binding to the oil/water interface. In sharp contrast, bacteria cultured in oil spill conditions become partially hydrophobic and their amphiphilicity drives them to oil/water interfaces, where they reduce interfacial tension and form the early stages of a biofilm. We show that it is A. borkumensis cells that attach to the oil/water interface and not a synthesized biosurfactant that is released into solution that reduces interfacial tension. This study provides key insights into the physicochemical properties that allow A. borkumensis to adhere to oil/water interfaces.

T/B APEX 3508: Best Practices for Detection and Recovery of Sunken Oil

ABSTRACT On September 2, 2015, two towing vessels collided on the Lower Mississippi River at Mile 937, near Columbus, Kentucky, resulting in the complete breach of the #3 starboard cargo tank on the T/B APEX 3508 and the release of 120,588 gallons of clarified slurry oil (CSO; Group V oil; Specific Gravity: 1.14) into the navigable waterway. The incident was classified as a Major Inland Spill in accordance with the National Oil and Hazardous Substance Contingency Plan and a Major Marine Casualty that was jointly investigated by the United States Coast Guard and the National Transportation Safety Board. Over flights conducted as far as 20 miles downriver indicated only light, sporadic sheening for 1–2 days. On-water and shoreline assessments conducted up to six miles downriver revealed no visible signs of surface oiling. Based on its properties, the vast majority of the CSO was presumed to have sunk, but its precise disposition and location was not confirmed. Using side scan sonar (SSS) technology, two distinct subsurface anomalies with an approximate combined area of 9,200 m2 were identified on the river bed in the vicinity of the incident. The anomalies were confirmed as oil by divers and direct sampling, and were then divided into 25 m grids for identification and tracking. The Unified Command evaluated best available technologies and determined that GPS guided environmental dredging would be the safest, most effective and efficient of the recovery options. The established cleanup endpoint was a maximum of 10% sporadic oil distribution in each grid. Two endangered mussel species were identified as potentially inhabiting the affected area. A diver survey was conducted in the area and concluded that bottom habitat was not likely to support the listed species. Further consultations with the resource manager indicated that proposed recovery operations posed low risk to the species. Recovery operations commenced on September 15, 2015 and concluded on September 25, 2015. Endpoint verification was conducted via SSS. In total, response operations lasted 23 days (eight operational periods), involved over 120 responders and 75 specialized response assets, and cost approximately $5 million. Approximately 2,524 m3 of dredged material (liquid and solids) were removed. After decanting, approximately 1,730 m3of oiled solids representing approximately 50 to 75% of the spilled product was recovered. This case serves as a benchmark for sunken oil detection and recovery operations, and identified many best practices that should be considered on future cases with similar spill conditions.

Experimental simulation of crude oil-water partitioning behavior of BTEX compounds during a deep submarine oil spill

The conventional shake flask technique for determining oil-water partition ratios of benzene, toluene, ethylbenzene and xylene (BTEX) cannot accurately assess the extremes of high pressure and low water temperatures found in submarine oil spill conditions. An oil-water partitioning device has been constructed to experimentally simulate the partition behavior of BTEX compounds under submarine oil spill conditions, using simulated live oil (methane-charged), with saline waters over a range of pressure (2–15MPa) and temperature (4–20°C). Within the investigated ranges, the partition ratios of BTEX compounds increase proportionally with an increase in methane charging pressure (oil saturation pressure) and the degree of BTEX alkylation, and decrease with increase in temperature. The variation of the partition ratio values due to changes in system pressure and increasing oil methane concentration, is much more significant than those seen due to change in the temperature over the range studied. This data may be used in near-field and far-field distribution modeling of the environmental fate of highly toxic BTEX compounds, derived from submarine oil spills and their impact on the ecosystem. The parameters will also aid in the prediction of oil migration and dispersion away from the spill thus helping to improve response strategies.

The effect of Coriolis force on oil slick transport and spreading at sea

ABSTRACTIn the present paper we propose an improved Nihoul's model which accounts for the main forces acting on an oil slick and ruling its spreading and transport in the first tens of hours after the spill. In the original model, Nihoul considered the Coriolis force to be negligible; we re-formulate Nihoul's analysis including the Coriolis force in the mathematical model. Coriolis force is found to act on both the oil slick transport and spreading processes in a non-trivial way and depends on several parameters. We numerically assess the importance of the Coriolis force on oil slick transport at different latitudes and spill conditions. Simulations carried out considering different model conditions show that the use of empirical parametrizations of the drift angle, when applied together with hydrodynamic models, leads to incorrect prediction of the slick trajectory. Finally we propose an empirical, simplified formulation which describes the trajectory of the oil slick's centre of mass considering the Coriolis deviation.

Risk assessment of oil spills along the Mediterranean coast: A sensitivity analysis of the choice of hazard quantification

Oil pollution in the Mediterranean represents a serious threat to the coastal environment. Quantifying the risks associated with a potential spill is often based on results generated from oil spill models. In this study, MEDSLIK-II, an EU funded and endorsed oil spill model, is used to assess potential oil spill scenarios at four pilot areas located along the northern, eastern, and southern Mediterranean shoreline, providing a wide range of spill conditions and coastal geomorphological characteristics. Oil spill risk assessment at the four pilot areas was quantified as a function of three oil pollution metrics that include the susceptibility of oiling per beach segment, the average volume of oiling expected in the event of beaching, and the average oil beaching time. The results show that while the three pollution metrics tend to agree in their hazard characterization when the shoreline morphology is simple, considerable differences in the quantification of the associated hazard is possible under complex coastal morphologies. These differences proved to greatly alter the evaluation of environmental risks. An integrative hazard index is proposed that encompasses the three simulated pollution metrics. The index promises to shed light on oil spill hazards that can be universally applied across the Mediterranean basin by integrating it with the unified oil spill risk assessment tool developed by the Regional Marine Pollution Emergency Response Centre for the Mediterranean (REMPEC).

Determination of sulfur in soil and plant media using wavelength dispersive X-ray fluorescence spectrometry as a tool for assessment of chemical spills

Sulfuric acid, a highly corrosive substance with a high risk of accidental spills, is important worldwide as a raw material in chemical production. This research aims to develop the best analytical method to determine sulfur contents from the accidental spill sites of sulfuric acid. Wavelength dispersive X-ray fluorescence (WDXRF) spectrometry was selected because of its suitability for mass solid samples and calibration standards were prepared to fit the spill conditions. When the calibration standards were prepared by a solution spiking method, the sulfur concentration showed large differences, especially at the 5.0wt.% as sulfur standard, for which a concentration of only 4.40wt.% was detected using inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis. Therefore, the method of reagent addition to the base material was selected in this study. Natural soil and purchased cellulose powder were used as the base material and calcium sulfate as the reagent. The instrument conditions, such as tube current, generator voltage, and measuring time, were tested with two instruments from different manufacturers and were subsequently optimized. The detectable concentration range of sulfur in this research was 0.001–23.6wt.% in soil media and 0.002–4.0wt.% in plant media. When six samples from the spilled site were analyzed, the results of WDXRF spectrometry showed 80–117% recovery compared with those from ICP-AES after microwave-assisted acid digestion as reference values.

Assessing human exposure and odor detection during showering with crude 4-(methylcyclohexyl)methanol (MCHM) contaminated drinking water

In 2014, crude (4-methylcyclohexyl)methanol (MCHM) spilled, contaminating the drinking water of 300,000 West Virginians and requiring “do not use” orders to protect human health. When the spill occurred, known crude MCHM physicochemical properties were insufficient to predict human inhalation and ingestion exposures. Objectives are (1) determine Henry's Law Constants (HLCs) for 4-MCHM isomers at 7, 25, 40, and 80°C using gas chromatography; (2) predict air concentrations of 4-MCHM and methyl-4-methylcyclohexanecarboxylate (MMCHC) during showering using an established shower model; (3) estimate human ingestion and inhalation exposure to 4-MCHM and MMCHC; and (4) determine if predicted air 4-MCHM exceeded odor threshold concentrations. Dimensionless HLCs of crude cis- and trans-4-MCHM were measured to be 1.42×10−4±6% and 3.08×10−4±3% at 25°C, respectively, and increase exponentially with temperature as predicted by the van't Hoff equation. Shower air concentrations for cis- and trans-4-MCHM are predicted to be 0.089 and 0.390ppm-v respectively after 10min, exceeding the US EPA's 0.01ppm-v air screening level during initial spill conditions. Human exposure doses were predicted using measured drinking water and predicted shower air concentrations and found to greatly exceed available guidance levels in the days directly following the spill. Odors would be rapidly detected by 50% of individuals at aqueous concentrations below analytical gas chromatographic detection limits. MMCHC, a minor odorous component (0.935%) of crude MCHM, is also highly volatile and therefore is predicted to contribute to inhalation exposures and odors experienced by consumers.

The effects of a remediated fly ash spill and weather conditions on reproductive success and offspring development in tree swallows.

Animals are exposed to natural and anthropogenic stressors during reproduction that may individually or interactively influence reproductive success and offspring development. We examined the effects of weather conditions, exposure to element contamination from a recently remediated fly ash spill, and the interaction between these factors on reproductive success and growth of tree swallows (Tachycineta bicolor) across nine colonies. Females breeding in colonies impacted by the spill transferred greater concentrations of mercury (Hg), selenium (Se), strontium, and thallium to their eggs than females in reference colonies. Parental provisioning of emerging aquatic insects resulted in greater blood Se concentrations in nestlings in impacted colonies compared to reference colonies, and these concentrations remained stable across 2years. Egg and blood element concentrations were unrelated to reproductive success or nestling condition. Greater rainfall and higher ambient temperatures during incubation were later associated with longer wing lengths in nestlings, particularly in 2011. Higher ambient temperatures and greater Se exposure posthatch were associated with longer wing lengths in 2011 while in 2012, blood Se concentrations were positively related to wing length irrespective of temperature. We found that unseasonably cold weather was associated with reduced hatching and fledging success among all colonies, but there was no interactive effect between element exposure and inclement weather. Given that blood Se concentrations in some nestlings exceeded the lower threshold of concern, and concentrations of Se in blood and Hg in eggs are not yet declining, future studies should continue to monitor exposure and effects on insectivorous wildlife in the area.