Fishermen and the Risk of Toxic Fumes from the Fish Storage Tanks

Haroon H, Naik SB. Fishermen and the Risk of Toxic Fumes from the Fish Storage Tanks. Indian J Crit Care Med 2024;28(3):307-308.

Methane emissions from oil and gas production sites and their storage tanks in West Virginia

A measurement campaign characterized methane and other emissions from 15 natural gas production sites. Sites were surveyed using optical gas imaging (OGI) cameras to identify fugitive and vented emissions, with the methane mass emission rate quantified using a full flow sampler. We present storage tank emissions in context of all site emissions, followed by a detailed account of the former. In total, 224 well pad emission sources at 15 sites were quantified yielding a total emission rate of 57.5 ± 2.89 kg/hr for all sites. Site specific emissions ranged from 0.4 to 10.5 kg/hr with arithmetic and geometric means of 3.8 and 2.2 kg/hr, respectively. The two largest categories of emissions by mass were pneumatic devices (35 kg/hr or ~61% of total) and tanks (14.3 kg/hr or ~25% of total). Produced water and condensate tanks at all sites employed emissions control devices. Nevertheless, tanks may still lose gas via component leaks as observed in this study. The total number of tanks at all sites was 153. One site experienced a major malfunction and direct tank measurements were not conducted due to safety concerns and may have represented a super-emitter as found in other studies. The remaining sites had 143 tanks, which accounted for 42 emissions sources. Leaks on controlled tanks were associated with ERVs, PRVs, and thief hatches. Since measurements represented snapshots-in-time and could only be compared with modeled tank emission data, it was difficult to assess real capture efficiencies accurately. Our estimates suggest that capture efficiency ranged from 63 to 92% for controlled tanks.

Assessment of water quality variations from mains to building storage tanks in Sharjah, United Arab Emirates

Continuous vigilance of water quality is essential throughout water supply and storage systems to ensure safe water quality and safeguard consumer health. In the present study, sixty-three sampling locations in Sharjah, UAE, were assessed for possible water quality variations from water supply through utilized water storage tanks in buildings. All investigated physico-chemical parameters were within national water quality guidelines except for free residual chlorine (< 0.2 mg/L in 30% of samples), mainly in storage tanks. Compliance of metal concentrations varied with metal type, sampling locations, and points. Highest compliance was reported for manganese, copper, nickel, chromium, and least for iron, lead, and cadmium. No major variations in physico-chemical water quality could be statistically observed using analysis of variance when tracing the water from lower tanks to upper tanks, yet significant variations for turbidity (p = 0.006) were observed from mains to lower tanks and for water temperature (p = 0.026), residual chlorine (p = 0.001), turbidity (p = 0.048), chromium (p = 0.019), copper (p = 0.002), manganese (p = 0.012), and zinc and lead (p = 0.000) from mains to upper tanks. As for investigated microbiological parameters, all investigated samples were completely free from total and fecal coliforms and Pseudomonas aeruginosa. Exhibited ranges of yeasts and molds (0-28 CFU/100 mL) and heterotrophic plate counts (0-356 CFU/mL), though non-enforceable parameters, were always lower than recommended water quality guidelines. Furthermore, Pearson correlation tests exhibited significant correlations for water temperature versus yeasts and molds and electrical conductivity versus sodium and potassium. Statistically (using t-tests), mean heterotrophic plate counts were slightly higher in lower tanks compared to other sampling points. Additionally, mean heterotrophic plate counts were significantly higher in larger tanks exceeding 2000 gallons, in square/rectangular shaped tanks, in tanks exceeding 10 years of age, and in concrete tanks with higher water temperatures. Re-chlorination, proper cleaning, as well as maintenance or upgrade of water storage tanks remain advisable to ensure safe water at point of use.

Quantifying the benefits of in-time and in-place responses to remediate acute LNAPL release incidents

Acute large volume spills from storage tanks of petroleum hydrocarbons as light non aqueous phase liquids (LNAPLs) can contaminate soil and groundwater and may have the potential to pose explosive and other risks. In consideration of an acute LNAPL release scenario, we explore the value of a rapid remediation response, and the value of installing remediation infrastructure in close proximity to the spill location, in effecting greater recovery of LNAPL mass from the subsurface. For the first time, a verified three-dimensional multi-phase numerical framework and supercomputing resources was applied to explore the significance of in-time and in-place remediation actions. A sand aquifer, two release volumes and a low viscosity LNAPL were considered in key scenarios. The time of commencement of LNAPL remediation activities and the location of recovery wells were assessed requiring asymmetric computational considerations. The volume of LNAPL released considerably affected the depth of LNAPL penetration below the groundwater table, the radius of the plume over time and the recoverable LNAPL mass. The remediation efficiency was almost linearly correlated with the commencement time, but was a non-linear function of the distance of an extraction well from the spill release point. The ratio of the recovered LNAPL in a well located at the centre of the spill/release compared to a well located 5 m away was more than 3.5, for recovery starting only 7 days after the release. Early commencement of remediation with a recovery well located at the centre of the plume was estimated to recover 190 times more LNAPL mass than a one-month delayed commencement through a well 15 m away from the centre of the LNAPL plume. Optimally, nearly 40% of the initially released LNAPL could be recovered within two months of commencing LNAPL recovery actions.

Multi-criteria decision approach for evaluation, ranking, and selection of remediation options: case of polluted groundwater, Kuwait

Freshwater groundwater resources at north Kuwait were contaminated by infiltrated oil as well as sea water that was used to fight the oil-well fires during the liberation of Kuwait in 1991. This paper investigates the feasibility of five remediation options to restore the polluted aquifers. These options include: (i) pump and treat of contaminated groundwater; (ii) cleaning the aquifer formation; (iii) construction of additional desalination plant; (iv) constructing additional storage tanks, and (v) development of artificial aquifer recharge schemes. The basis for this assessment study is to supply minimum basic drinking water to Kuwait City at a total rate of 50,000 m³/day in an emergency for up to one year based on essential basic need of 32 liters per capita per day. To compare these options, a decision matrix to select suitable remediation options using Multiple Criteria Decision Analysis (MCDA) approach is developed. The cost was given a relative weight of 20 whereas other criteria are given weight of 10. Based on these MCDA scores, it was found that option 3, namely, establishing an additional water desalination plant, is the most feasible option followed by option 5, artificial recharge of aquifers.

Development of a storm surge driven water quality model to simulate spills during hurricanes

Hurricanes can cause widespread environmental pollution that has yet to be fully articulated. This study develops a predictive water quality model to forecast potential contamination resulting from buckled or ruptured storage tanks in coastal industrialized areas when subjected to storm surge. The developed EFDC-Storm Surge model (EFDC-SS) couples EPA's EFDC code with the SWAN-ADCIRC hurricane simulation model. EFDC-SS is demonstrated using the Houston Ship Channel in Texas as a testbed and hurricane Ike as a model hurricane. Conservative and decaying dye runs evaluated various hurricane scenarios, combined with spills released at different locations and release times. Results showed that tank locations with shorter distances to the main waterbody and lower ground elevations have a higher risk of inundation and rapid spill mass transport. It was also determined that hurricane strength and landfall location, the location of the spill, and the spill release time relative to peak surge were interdependent.

Optimization of storage tank locations in an urban stormwater drainage system using a two-stage approach

Storage is important for flood mitigation and non-point source pollution control. However, to seek a cost-effective design scheme for storage tanks is very complex. This paper presents a two-stage optimization framework to find an optimal scheme for storage tanks using storm water management model (SWMM). The objectives are to minimize flooding, total suspended solids (TSS) load and storage cost. The framework includes two modules: (i) the analytical module, which evaluates and ranks the flooding nodes with the analytic hierarchy process (AHP) using two indicators (flood depth and flood duration), and then obtains the preliminary scheme by calculating two efficiency indicators (flood reduction efficiency and TSS reduction efficiency); (ii) the iteration module, which obtains an optimal scheme using a generalized pattern search (GPS) method based on the preliminary scheme generated by the analytical module. The proposed approach was applied to a catchment in CZ city, China, to test its capability in choosing design alternatives. Different rainfall scenarios are considered to test its robustness. The results demonstrate that the optimal framework is feasible, and the optimization is fast based on the preliminary scheme. The optimized scheme is better than the preliminary scheme for reducing runoff and pollutant loads under a given storage cost. The multi-objective optimization framework presented in this paper may be useful in finding the best scheme of storage tanks or low impact development (LID) controls.

[Presence of Legionella spp. in household drinking water reservoirs in Resistencia, Chaco, Argentina. Preliminary report]

Legionella spp. is an environmental bacterium that can survive in a wide range of physicochemical conditions and may colonize distribution systems of drinking water and storage tanks. Legionella pneumophila is the major waterborne pathogen that can cause 90% of Legionnaires' disease cases. The aim of this study was to detect the presence of Legionella spp. in household drinking water tanks in the city of Resistencia, Chaco. The detection of Legionella in water samples was performed by culture methods as set out in ISO 11731:1998. Thirty two water samples were analyzed and Legionella spp. was recovered in 12 (37.5%) of them. The monitoring of this microorganism in drinking water is the first step towards addressing the control of its spread to susceptible hosts.