scholarly journals The Characteristics of Shallow Groundwater in Petroleum Contaminated Site and the Assessment of Efficiency of Biopile by Off-gas Analysis

2013 ◽  
Vol 18 (2) ◽  
pp. 36-44 ◽  
Author(s):  
Chang-Hwan Cho ◽  
Ki-June Sung
Keyword(s):  
Shallow Groundwater ◽  
Gas Analysis ◽  
Contaminated Site

scholarly journals Analysis of Hydrogeochemical Characteristics and Origins of Chromium Contamination in Groundwater at a Site in Xinxiang City, Henan Province

2021 ◽  
Vol 11 (24) ◽  
pp. 11683
Author(s):  
Wenfang Chen ◽  
Yaobin Zhang ◽  
Weiwei Shi ◽  
Yali Cui ◽  
Qiulan Zhang ◽  
...  
Keyword(s):  
Hexavalent Chromium ◽  
Groundwater Remediation ◽  
Saturation Index ◽  
Shallow Groundwater ◽  
Distribution Patterns ◽  
Scientific Basis ◽  
Henan Province ◽  
Contaminated Site ◽  
Control Mechanisms ◽  
Chromium Contamination

Hexavalent chromium contamination in groundwater has become a very serious and challenging problem. Identification of the groundwater chemical characteristics of the sites and their control mechanisms for remediation of pollutants is a significant challenge. In this study, a contaminated site in Xinxiang City, Henan Province, was investigated and 92 groundwater samples were collected from the site. Furthermore, the hydrogeochemical characteristics and the distribution patterns of components in the groundwater were analyzed by a combination of multivariate statistical analysis, Piper diagram, Gibbs diagram, ions ratio and hydrogeochemical simulation. The results showed that the HCO3-Cl-Mg-Ca type, SO4-HCO3-Na type, and HCO3-Mg-Ca-Na type characterize the hydrogeochemical composition of shallow groundwater and HCO3-Cl-Mg-Ca type, HCO3-Na-Mg type, and HCO3-SO4-Mg-Na-Ca type characterize the hydrogeochemical composition of deep groundwater. Ion ratios and saturation index indicated that the groundwater hydrogeochemical characteristics of the study area are mainly controlled by water–rock action and evaporative crystallization. The dissolution of halite, gypsum and anhydrite, the precipitation of aragonite, calcite and dolomite, and the precipitation of trivalent chromium minerals other than CrCl3 and the dissolution of hexavalent chromium minerals occurred in groundwater at the site. The minimum value of pH in groundwater at the site is 7.55 and the maximum value is 9.26. The influence of pH on the fugacity state of minerals was further investigated. It was concluded that the saturation index of dolomite, calcite, aragonite and MgCr2O4 increases with the increase of pH, indicating that these minerals are more prone to precipitation, and the saturation index of Na2Cr2O7, K2Cr2O7 and CrCl3 decreases with the increase of pH, implying that Na2Cr2O7, K2Cr2O7 and CrCl3 are more prone to dissolution. The saturation index of the remaining minerals is less affected by pH changes. The study can provide a scientific basis for groundwater remediation.

scholarly journals Effects of Cone Penetrometer Testing on Shallow Hydrogeology at a Contaminated Site

2022 ◽  
Vol 9 ◽  
Author(s):  
Andrew D. Putt ◽  
Erin R. Kelly ◽  
Kenneth A. Lowe ◽  
Miguel Rodriguez ◽  
Terry C. Hazen
Keyword(s):  
Water Level ◽  
Specific Conductivity ◽  
Shallow Groundwater ◽  
Contaminated Sites ◽  
Contaminated Site ◽  
Cone Penetrometer ◽  
Monitoring Networks ◽  
Penetration Testing ◽  
Geochemical Parameters ◽  
Cone Penetrometer Testing

Penetration testing is a popular and instantaneous technique for subsurface mapping, contaminant tracking, and the determination of soil characteristics. While the small footprint and reproducibility of cone penetrometer testing makes it an ideal method for in-situ subsurface investigations at contaminated sites, the effects to local shallow groundwater wells and measurable influence on monitoring networks common at contaminated sites is unknown. Physical and geochemical parameters associated with cone penetrometer testing were measured from a transect of shallow groundwater monitoring wells adjacent to penetrometer testing. For wells screened above the depth of cone refusal, the physical advancement and retraction of the cone had a significant effect (p < 0.01) on water level for several pushes within 10 meters of a monitoring well, and a measured increase in specific conductivity. No effect on geochemistry or water level was observed in continuous monitoring data from wells screened below the depth of cone refusal, but variability in specific conductivity from these wells during penetration testing was only a fraction of the natural variation measured during precipitation events. Continuous measurements of specific conductivity and water level demonstrated that the effects of penetration testing have limited spatial and temporal distributions with a null effect post-testing.

Finding the Information of the Unknown DNAPL Residual Source using various tracer data, Wonju, Korea

2020 ◽  
Author(s):  
Seong-Sun Lee ◽  
Il-Ryoung Cho ◽  
Yeojin Ju ◽  
Kang-Kun Lee
Keyword(s):  
Analytical Solution ◽  
Noble Gas ◽  
Quantitative Information ◽  
Gas Analysis ◽  
Monitoring Data ◽  
Source Zone ◽  
Contaminated Site ◽  
Remedial Action ◽  
Rayleigh Fractionation ◽  
Source Mass

<p>In this study, analytical solution method which can evaluate and quantify the impacts of partial mass reduction by remedial action performed in study site is applied to estimate the unknown DNAPL source mass and dissolved concentration using long-term monitoring data collected from 2009 to 2019. Also, noble gas tracer method was applied to identify the partitioning processes which can be happened in TCE contaminated site. By using the source zone monitoring data during about 10 years and analytical solution, initial dissolved concentration and residual mass of TCE in spilled period at the main source zone were roughly estimated 150 mg/L and 1000 kg, respectively. These values decreased to 0.45 mg/L and 33.07 kg direct after an intensive remedial action performed in 2013 and then it expected to be continuously decreased to 0.29 mg/L and 25.41 kg from the end of remedial actions to 2020. From results of quantitative evaluation using analytical solution, it can be evaluated that the intensive remedial action had effectively performed with removal efficiency of 70% for the residual source mass during the remediation period. From the results of noble gas analysis, the distance from TCE source zone was divided into three groups from Zone 1 to 3. Zone 1 includes samples that are the closest from the TCE main source, and are highly partitioned to TCE compared to other zones. Zone 3 samples show least accordance with either of the fractionation lines, showing that sampling points are influenced highly by other mechanism rather than partitioning to TCE. Also, it is identified that seasonal variation of groundwater level can be affected to the distribution of noble gas at around TCE source zone. Samples from only “High TCE” zone are plotted along with ideal batch equilibrium and Rayleigh fractionation line again and divided into two groups according to their sampling date. From August 2018 to October, 2018, samples shift from right to left in the figure, getting closer to Rayleigh fractionation line. In August, noble gas was relatively in equilibrium between groundwater and TCE. However, as water table rises, noble gas became touch with residual TCE locating above the previous water-level, which is a receiving fluid in water-TCE system. Results of this study was support that it was able to estimate the unknown quantitative information for TCE contamination and noble gas as the indicator of DNAPL contamination could be applied in allocating the DNAPL source which is relatively hard to estimate.</p>

Locomotive Boiler Flue Gas Analysis*

1912 ◽  
Vol 74 (1914supp) ◽  
pp. 159-160
Author(s):  
Lawford H. Fry
Keyword(s):  
Flue Gas ◽  
Gas Analysis

Efficacy of Near-Infrared Spectrometry for Monitoring the Cerebral Effects of Severe Dilutional Anemia

2014 ◽  
Vol 17 (3) ◽  
pp. 154 ◽  
Author(s):  
Arıtürk Cem ◽  
Ustalar Serpil ◽  
Toraman Fevzi ◽  
Ökten Murat ◽  
Güllü Ümit ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cardiac Surgery ◽  
Blood Lactate ◽  
Near Infrared ◽  
Bypass Graft ◽  
Blood Gas Analysis ◽  
Gas Analysis ◽  
Infrared Spectrometry ◽  
Control Group ◽  
Near Infrared Spectrometry

<p><strong>Introduction:</strong> Clear guidelines for red cell transfusion during cardiac surgery have not yet been established. The current focus on blood conservation during cardiac surgery has increased the urgency to determine the minimum safe hematocrit for these patients. The aim of this study was to determine whether monitoring of cerebral regional oxygen saturation (rSO<sub>2</sub>) via near-infrared spectrometry (NIRS) is effective for assessing the cerebral effects of severe dilutional anemia during elective coronary arterial bypass graft surgery (CABG).</p><p><strong>Methods:</strong> The prospective observational study involved patients who underwent cerebral rSO<sub>2</sub> monitoring by NIRS during elective isolated first-time CABG: an anemic group (<em>N</em>=15) (minimum Hemoglobin (Hb) N=15) (Hb &gt;8 g/dL during CPB). Mean arterial pressure (MAP), pump blood flow, blood lactate level, pCO<sub>2</sub>, pO<sub>2</sub> at five time points and cross-clamp time, extracorporeal circulation time were recorded for each patient. Group results statistically were compared.</p><p><strong>Results:</strong> The anemic group had significantly lower mean preoperative Hb than the control group (10.3 mg/dL versus 14.2 mg/dL; <em>P</em> = .001). The lowest Hb levels were observed in the hypothermic period of CPB in the anemic group. None of the controls exhibited a &gt;20% decrease in cerebral rSO<sub>2</sub>. Eleven (73.3%) of the anemic patients required an increase in pump blood flow to raise their cerebral rSO<sub>2</sub>.</p><p><strong>Conclusions:</strong> In this study, the changes in cerebral rSO<sub>2</sub> in the patients with low Hb were within acceptable limits, and this was in concordance with the blood lactate levels and blood-gas analysis. It can be suggested that NIRS monitoring of cerebral rSO<sub>2</sub> can assist in decision making related to blood transfusion and dilutional anemia during CPB.</p>

Blood gas analysis in newborns with low cardiac output syndrome after cardiac surgery.

2018 ◽  
Vol 19 (5) ◽  
pp. 676-687
Author(s):  
G.G. Khubulava ◽  
A.B. Naumov ◽  
S.P. Marchenko ◽  
O.Yu. Chupaeva ◽  
A.A. Seliverstova ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Cardiac Surgery ◽  
Blood Gas Analysis ◽  
Gas Analysis ◽  
Blood Gas ◽  
Low Cardiac Output Syndrome ◽  
Low Cardiac Output

Application of the EPA hydrocarbon spill screening model to a hydrocarbon contaminated site in Thailand

2002 ◽  
Vol 10 (1) ◽  
pp. 17-24
Author(s):  
Vasin Mahatnirunkul ◽  
Sirintornthep Towprayoon ◽  
Vladimir Bashkin
Keyword(s):  
Contaminated Site ◽  
Screening Model ◽  
Hydrocarbon Spill

Thermal soak compatibility test and residual gas analysis on 4130 steel and methanol thermosyphons

1997 ◽  
Author(s):  
Q. He ◽  
Pon Ponnappan ◽  
J. Brown ◽  
Q. He ◽  
Pon Ponnappan ◽  
...  
Keyword(s):  
Gas Analysis ◽  
Compatibility Test ◽  
Residual Gas
Sign in / Sign up

Export Citation Format

Share Document