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Fast-Track Remedial Design of Full-Scale ISCO Application Using Pilot Scale Testing and Field Screening Parameters
As a result of drum re-finishing operations, soil and groundwater at the Ottati and Goss Superfund Site in Kingston, NH are contaminated with chlorinated volatile organic compounds (VOCs); benzene, toluene, ethylbenzene, and xylene (BTEX); and 1,4-dioxane. After re-evaluation of the selected remedy for groundwater, pump and treat, EPA changed the remediation approach to in-situ chemical oxidation (ISCO) through an Amended Record of Decision in September 2007. At that time, EPA established a goal for the site to attain construction complete status within one year, by September 30, 2008.
Activated persulfate was selected as the chemical oxidant for its capability to oxidize 1,4-dioxane, in addition to the other VOC contaminants of concern. Bench-scale and field pilot scale test were completed in three source areas to collect site-specific information to evaluate persulfate\u27s ability to destroy the contaminants of concern and to optimize full-scale remediation design in three discrete source areas at the site. Base-activated persulfate was injected in Areas A and B in December 2007, and pilot test injection was completed in Area C in early February 2008, after vertical profiling was completed throughout Area C. Groundwater sampling for laboratory analysis was planned for 6 and 12 weeks after injection in each area; however, it was known during pilot test planning that the full-scale design would need to be completed by the end of March 2008, before all laboratory results would be available. In order to complete the design, an intensive evaluation of field geochemistry parameters and field screening chemical analysis was performed to assess radius of influence, oxidant persistence, and aquifer behavior. Field screening analyses included residual persulfate via a permanganate titration, sulfate via colorimetry, and sodium via an ion-selective electrode. The field screening and field geochemistry results were used heavily in completing the full-scale ISCO design. The laboratory analytical results noted significant decreases in concentrations of chemicals of concern in wells where geochemistry and field parameters were observed to change. This article discusses pilot test planning, performance monitoring, and full-scale design using data collected from the pilot test for this fast-track remediation. The full-scale application was completed between July and September 2008, and was the third largest single-site application of persulfate performed to date
Geophysical Analysis of Basement Terrain Groundwater Using Vertical Electrical Sounding: A Case Study of Parts of Abuja North Central Nigeria
The successful exploitation of groundwater requires a proper understanding of the
hydrogeological characteristics of the sub-surface aquifers found within the basement
complex. This can be carried out using various geophysical survey methods. Groundwater
occurs in the joints, fissures, fractures, shear zones and weathered overburden of
un-weathered rocks. Therefore effective groundwater development requires careful
geophysical analysis and interpretation of data. The use of vertical electrical sounding (VES)
for groundwater (hydrogeological) exploration is popular in the basement complex rocks
and sedimentary basins. This study was aimed at analysing the hydro geological
characteristics such as bedrock depth, lithological units and degree of fracturing and drilling
location of groundwater in the basement complex / terrain of Garki, Kurudu, Dei-Dei and
Kubwa areas of Abuja, North central Nigeria using Resistivity Method. Finally, the results
indicate that the choice of geophysical survey method determined by physical properties of
the area; influence groundwater availability, susceptibility and supply
Geophysical Analysis of Basement Terrain Groundwater Using Vertical Electrical Sounding: A Case Study of Parts of Abuja North Central Nigeria
The successful exploitation of groundwater requires a proper understanding of the
hydrogeological characteristics of the sub-surface aquifers found within the basement
complex. This can be carried out using various geophysical survey methods. Groundwater
occurs in the joints, fissures, fractures, shear zones and weathered overburden of
un-weathered rocks. Therefore effective groundwater development requires careful
geophysical analysis and interpretation of data. The use of vertical electrical sounding (VES)
for groundwater (hydrogeological) exploration is popular in the basement complex rocks
and sedimentary basins. This study was aimed at analysing the hydro geological
characteristics such as bedrock depth, lithological units and degree of fracturing and drilling
location of groundwater in the basement complex / terrain of Garki, Kurudu, Dei-Dei and
Kubwa areas of Abuja, North central Nigeria using Resistivity Method. Finally, the results
indicate that the choice of geophysical survey method determined by physical properties of
the area; influence groundwater availability, susceptibility and supply
Method of Monte Carlo grid for data analysis
This paper presents an analysis procedure for experimental data using
theoretical functions generated by Monte Carlo. Applying the classical
chi-square fitting procedure for some multiparameter systems is extremely
difficult due to a lack of an analytical expression for the theoretical
functions describing the system. The proposed algorithm is based on the least
square method using a grid of Monte Carlo generated functions each
corresponding to definite values of the minimization parameters. It is used for
the E742 experiment (TRIUMF, Vancouver, Canada) data analysis with the aim to
extract muonic atom scattering parameters on solid hydrogen.Comment: 16 pages, 10 figures, submitted to NI
Volume Comparison for Hypersurfaces in Lorentzian Manifolds and Singularity Theorems
We develop area and volume comparison theorems for the evolution of
spacelike, acausal, causally complete hypersurfaces in Lorentzian manifolds,
where one has a lower bound on the Ricci tensor along timelike curves, and an
upper bound on the mean curvature of the hypersurface. Using these results, we
give a new proof of Hawking's singularity theorem.Comment: 15 pages, LaTe
A Sublinear Variance Bound for Solutions of a Random Hamilton Jacobi Equation
We estimate the variance of the value function for a random optimal control
problem. The value function is the solution of a Hamilton-Jacobi
equation with random Hamiltonian
in dimension . It is known that homogenization occurs as , but little is known about the statistical fluctuations of .
Our main result shows that the variance of the solution is bounded
by . The proof relies on a modified Poincar\'e
inequality of Talagrand
The wave equation on singular space-times
We prove local unique solvability of the wave equation for a large class of
weakly singular, locally bounded space-time metrics in a suitable space of
generalised functions.Comment: Latex, 19 pages, 1 figure. Discussion of class of metrics covered by
our results and some examples added. Conclusion more detailed. Version to
appear in Communications in Mathematical Physic
Guidelines on the use of Structure from Motion Photogrammetry in Geomorphic Research
As a topographic modelling technique, structure-from-motion (SfM) photogrammetry combines the utility of digital photogrammetry with a flexibility and ease of use derived from multi-view computer vision methods. In conjunction with the rapidly increasing availability of imagery, particularly from unmanned aerial vehicles, SfM photogrammetry represents a powerful tool for geomorphological research. However, to fully realize this potential, its application must be carefully underpinned by photogrammetric considerations, surveys should be reported in sufficient detail to be repeatable (if practical) and results appropriately assessed to understand fully the potential errors involved. To deliver these goals, robust survey and reporting must be supported through (i) using appropriate survey design, (ii) applying suitable statistics to identify systematic error (bias) and to estimate precision within results, and (iii) propagating uncertainty estimates into the final data products
Guidelines on the use of Structure from Motion Photogrammetry in Geomorphic Research
As a topographic modelling technique, structure-from-motion (SfM) photogrammetry combines the utility of digital photogrammetry with a flexibility and ease of use derived from multi-view computer vision methods. In conjunction with the rapidly increasing availability of imagery, particularly from unmanned aerial vehicles, SfM photogrammetry represents a powerful tool for geomorphological research. However, to fully realize this potential, its application must be carefully underpinned by photogrammetric considerations, surveys should be reported in sufficient detail to be repeatable (if practical) and results appropriately assessed to understand fully the potential errors involved. To deliver these goals, robust survey and reporting must be supported through (i) using appropriate survey design, (ii) applying suitable statistics to identify systematic error (bias) and to estimate precision within results, and (iii) propagating uncertainty estimates into the final data products
Association and interaction analyses of eight genes under asthma linkage peaks
Background: Linkage studies have implicated the 2q33, 9p21, 11q13 and 20q13 regions in the regulation of allergic disease. The aim of this study was to test genetic variants in candidate genes from these regions for association with specific asthma traits. Methods: Ninety-five single nucleotide polymorphisms (SNP) located in eight genes (CD28, CTLA4, ICOS, ADAM23, ADAMTSL1, MS4A2, CDH26 and HRH3) were genotyped in >5000 individuals from Australian (n = 1162), Dutch (n = 99) and Danish (n = 303) families. Traits tested included doctor-diagnosed asthma, atopy, airway obstruction, total serum immunoglobulin (Ig) E levels and eosinophilia. Association was tested using both multivariate and univariate methods, with gene-wide thresholds for significance determined through simulation. Gene-by-gene and gene-by-environment analyses were also performed. Results: There was no overall evidence for association with seven of the eight genes tested when considering all genetic variation assayed in each gene. The exception was MS4A2 on chromosome 11q13, which showed weak evidence for association with IgE (gene-wide P < 0.05, rs502581). There were no significant gene-by-gene or gene-by-environment interaction effects after accounting for the number of tests performed. Conclusions: The individual variants genotyped in the 2q33, 9p21 and 20q13 regions do not explain a large fraction of the variation in the quantitative traits tested or have a major impact on asthma or atopy risk. Our results are consistent with a weak effect of MS4A2 polymorphisms on the variation of total IgE levels. © 2009 John Wiley & Sons A/S
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