On-site Laboratory Research Articles

Water-Rock Interaction Mechanisms and Hydrochemical Evolution in the Underground Reservoirs of Coal Mines.

Coal-mine underground reservoirs play pivotal roles in water purification through water-rock interactions; however, underlying mechanisms associated with water-rock interactions remain unclear to date. To address this issue, this study considered the underground reservoirs of the Daliuta coal mine, Shendong to conduct the analysis. Through onsite sampling and laboratory simulation experiments, along with hydrochemical-diagram-based analysis, multivariate statistical analysis, and hydrogeochemical simulations, the sources and evolutions of major ions associated with the water of the underground reservoirs were elucidated. Results revealed that the suspended-solid content, turbidity, electrical conductivity, and total dissolved solid concentration in the water at the outlet of the underground reservoirs decreased significantly compared to corresponding values at the inlet. Alteration in the hydrochemical type of water was observed from the Cl·HCO3-Na·Ca, Cl-Na·Ca·Mg, and Cl·SO4-Na types at the inlet of the reservoirs to SO4·Cl-Na at the outlet of the reservoirs. Further, the primary hydrogeochemical processes carried out along the water flow path in the underground reservoirs included mineral dissolution (including halite, silicate, calcite, gypsum, and anhydrite dissolution), pyrite oxidation, cation exchange, and clay-mineral adsorption. Water-rock interactions in the underground reservoirs can be categorized into three stages. The first stage was dominated by dissolution and oxidation, resulting in decreased water pH and overall increased concentrations of total dissolved solids along with major ions in the water. The second stage was dominated by clay-mineral adsorption and cation exchange, resulting in increased water pH and overall concentrations of Na+ and K+ as well as decreased concentrations of Ca2+, Mg2+, and total dissolved solids in the water body. The third stage was characterized by weak water-rock interactions, wherein the concentrations of total dissolved solids along with major ions, as well as the pH of the water stabilized. Thus, our research findings provide important theoretical references for understanding water-purification mechanisms and water-storage-duration optimization in coal-mine underground reservoirs.

B-148 Bacer: decentralized isotope dilution method with lab blinding for blood alcohol content

Abstract Background In legal medicine, the determination Blood Alcohol Content (BAC) usually faced the problems of insufficient sample size, ethanol degradation and impossible double check. In addition, the integrity of laboratory may also be questioned. To this end, we developed a decentralized solution based on isotope dilution method. Methods Patented deuterated ethanol vacuum tube was used in field as regular type, weight of blood was record to BACer terminal. Arbitrary amount of sample(ca.0.1-1.0g) was pipetted to GC sample vial and sealed tightly, then heated more than 2min at 70°C, 10µL headspace sample was injected into GC-MS. Blinded lab uploaded peak area ratio of ethanol/deuterated ethanol(mz31/33) to BACer to calculate the final BAC. Results Regression between peak area ratios of ethanol/deuterated ethanol showed good linearity in the range of 0.10-5.0 (R2>0.999). Regression equation of different instruments were proved good consistency with slopes ranged from 1.03 to 1.07, and the LOD and LOQ were around 0.01mg/g and 0.05mg/g, 3-level recoveries between 97%-101% with RSD less than 1%. During the 6-month stability test at 4°C and normal temperature, the blood sample test results maintained good stability. The proposed method was applied to 2021 CNAS proficiency testing (2021SF-CNAS002) organized by China Academy of Forensic Sciences with satisfactory results. The comparison with Chinese standard method SF/Z JD0107001-2010 yielded good agreement with Passing&Bablok test (P>0.10). The expanded uncertainty estimated by Monte-carlo method was less than 3%. Conclusions This proposed method showed the possibility of decentralized determination of BAC with lab blinding, the separation of on-site sampling data and laboratory testing also provided the possibility of integrity of results. It also provided a possible solution for the scenarios where the storage condition of blood collection is poor, or the cross check is required. But good chromatographic separation and operation are compulsive due to the possibility of interference in IDMS.

Evaluation of the quality of treated wastewater from the Fez wastewater treatment plant using wastewater quality index

Abstract The increasing urbanization of Fez, with its daily discharge of wastewater, raises environmental concerns. Therefore, this study assesses the quality of water treated by the Fez wastewater treatment plant, focusing on the summer and autumn seasons, preserving the Oued Sebou from pollution and evaluating treatment efficiency. Key parameters, including on-site measurements and laboratory analyses, indicate average efficiencies of 89.88% (BOD5), 88.41% (COD), and 94.47% (TSS), in compliance with discharge standards. In addition, the results of the principal component analysis (PCA) facilitated understanding of the physico-chemical analyses, underlining the global approach of the study.

Clinical Yield of Acute Inflammatory Markers in the Pediatric Emergency Department

The use of inflammatory markers (IMs) in the pediatric emergency department (PED) is broad and non-specific. This retrospective, cross-sectional study of children aged 3 months to 18 years evaluated the use of IMs in the PED. The reasons for IM use were provider practice (38%), ruling out a differential diagnosis (36%), and presence of comorbidities (18%). IMs are commonly used for gastroenterology, infectious diseases, and orthopedic diseases. A third had IMs without an indication. Forty-six percent of IM testing was indicated based on medical documentation, of which only 21% had abnormal IMs. Compared to the abnormal IM values by the on-site laboratory, the IM assessment using a receiver operating characteristic (ROC) curve threshold criterion had improved specificity and negative predictive value (NPV) based on the reason for IM use. This study suggests that the rate of abnormal IMs is low and does not affect patient outcomes in the PED.

Investigating the Microarchaeological Record at Underwater Sites: Operating an On-Site Laboratory During the Antikythera Shipwreck Excavation

AbstractUnderwater excavations require an immense amount of logistics and have inherent time limitations. Underwater challenges such as nitrogen toxicity, underwater color change, and dive time limits increase with working depths, affecting the interpretation of archaeological contexts. Thus, underwater excavations involve methods and approaches to extract the maximum information from small areas while providing a comprehensive understanding of the archaeological record. Here, we present the benefits of using an on-site laboratory comprising a microscope, binocular microscope, Fourier transform infrared spectrometer and blue light inspection device. Three case studies are presented, focusing on the identification of stratigraphic boundaries, as well as the preservation and identification of archaeological materials. The results show a complex stratigraphic sequence containing seven layers divided into four mineralogical units: (1) Calcite, (2) Calcite and aragonite, (3) Aragonite, and (4) Dolomite. Additionally, the use of an on-site laboratory is effective in preventing the misidentification of archaeological materials, which could affect the final interpretation of the archaeological site (e.g., glass, lead, bone), and enabling the identification of materials invisible to the naked eye, such as opaline phytoliths. In the case of the Antikythera shipwreck, the on-site laboratory facilitated the examination of stratigraphy and quality of the archaeological context while streamlining excavation practices and documentation. Furthermore, the on-site laboratory allowed for the assessment of material preservation and provide crucial insights to inform post-excavation treatments and analysis of artifacts.

Consequences of slope instability and existing practices of mitigation in hydropower projects of Nepal

IntroductionNepal has witnessed several instances of slope instability associated with Hydroelectric Projects in the recent decades. Despite this, slope instability tends to receive less attention compared to other hazards.ObjectivesThe objective of this study is to investigate fourteen hydroelectric projects with the aim of identifying the types and causes of slope failures. Additionally, it seeks to offer a comprehensive understanding of slope stability conditions and challenges encountered during construction at project sites.MethodsTo accomplish this, the study employs Key Informant Interviews with Questionnaires to delve into the slope stability concerns within Nepal’s hydropower projects. The findings are then validated through an extensive review of pertinent literature. To conduct a thorough assessment of slope stability, the study relies on on-site observations, measurements, investigations, and both in-situ and laboratory tests.ResultsIt becomes evident that the careful selection of study sites, the application of geotechnical methods, and the establishment of regular monitoring are pivotal for ensuring favorable slope stability outcomes.ConclusionA majority of respondents concur that cutslope is the primary factor causing slope instability with 44.4% answering affirmatively. An independent t-test reveals there is no significant difference between the variables. Moreover, the correlation which is closed to 1 suggests that perception of respondents are interconnected and tend to vary in a synchronized manner. Participants in the study widely acknowledge numerical modeling methods as a means to overcome the limitations of slope stability studies.

Genetic testing for inherited arrhythmia syndromes and cardiomyopathies: results of the European Heart Rhythm Association survey.

Indications and clinical impact of genetic testing for cardiac diseases have increased significantly over the past years. The aim of this physician-based European Heart Rhythm Association (EHRA) survey was to assess current clinical practice and access to genetic testing for cardiac diseases across European Society of Cardiology countries and to evaluate adherence to the 2022 EHRA/HRS/APHRS/LAHRS Expert Consensus Statement on genetic testing. An online questionnaire composed of 28 questions was submitted to the EHRA Research Network and European Reference Network GUARD-Heart healthcare partners and promoted via dedicated social media channels. There were 357 respondents from 69 countries, 40% working in a hospital setting with a cardiac genetic service and/or a dedicated clinic focusing on inherited cardiac diseases and 27% with an onsite genetic laboratory. No genetic testing or low annual rate (<10/year) was declared by 39% of respondents. The majority of respondents (78%) declared issues or limitations to genetic testing access in their clinical practice. The main reasons for not providing or limited access to genetic testing were no availability of dedicated unit or genetic laboratory (35%) or reimbursement issues (25%). The most frequently reported indication for genetic testing was diagnostic purpose (55%). Most respondents (92%) declared offering genetic testing preceded by genetic counselling and 42% regular multidisciplinary evaluations for patients with cardiac genetic diseases. The perceived value of genetic testing in the diagnostic, prognostic, and therapeutic assessment was variable (67, 39, and 29%, respectively) and primarily based on the specific inherited disease. The majority of respondents recommended cascade genetic testing for the first-degree family members in case of pathogenic/likely pathogenic variant in the proband. This survey highlights a significant heterogeneity of genetic testing access and provision and issues attributable to the availability of dedicated unit/genetic laboratory and reimbursement. However, adequate adherence to indications in the current recommendations for genetic testing in patients with cardiac diseases was observed.

Study on Variation Law of Hazardous Areas in Goaf Based on Coal Oxidation Kinetics Theory

ABSTRACT Regarding various problems on safety production in coal mines, residual coal in goaf’s spontaneous combustion is extensive, determining its hazardous areas is critical to extinguish or prevent fires in goaf. Taking production practices at the 010803-working face of Wang Wa Coal Mine as background, a combined approach involving on-site experiments, laboratory tests, and numerical simulations is adopted to investigate “three-zone” spontaneous combustion as well as the distribution patterns of temperature fields in shallowly buried coal seams. The mathematical and physical models of spontaneous combustion in goaf are constructed. Upon oxidation of coal at low temperatures, experimental data about the intensity of release of heat and the rate of consumption of oxygen inform the construction of a kinetic model for coal oxidation in goaf. Utilizing field-measured data on air leakage, a distribution model for permeability within the working face’s goaf is constructed. To study combustion “three-zone” and temperature field distribution patterns in goaf under various air supply volumes, as well as to quantitatively analyze the relationship between the width and area of oxidation zones, the area of high-temperature areas, and the distribution of high-temperature sites in the goaf, with relation to the working face’s supply volumes of air. The results show that the maximum simulated air leakage in the goaf of the working face is 148.03 m3/min, with a relative error of just 1.4% compared to the measured value. Furthermore, validation confirms that the simulated oxygen concentration variation pattern closely aligns with the measured oxygen concentration. As the airflow rate at the working face increases, the oxidation zone width at the intake side gradually grows. While on the return side, it gradually decreases, resulting in a maximum width difference of 22.6 m. The goaf area’s concentration of oxygen exhibits an “S” shape distribution pattern. The overall temperature change range within the high-temperature zone of the goaf is 4.5 K, gradually migrating toward the deeper areas. As the air supply rate rises, oxidation zone area gradually decreases, exhibiting an overall sinusoidal distribution. Concurrently, the high-temperature zone area progressively expands, conforming to a Boltzmann function distribution. When the Air supply rate is 800 m3/min to 1120 m3/min, the areas of the two are linearly correlated with the air supply volumes. Under varying air supply volumes, the position of the high-temperature point within the goaf changes in both strike and dip directions, and the relative distance with the intake air corner follows an exponential function in both strike and dip directions. Through comprehensive analysis, it is concluded that the actual air supply volume on-site should ideally range between 800 m3/min and 1120 m3/min. This range effectively prevents and controls the hazardous area of spontaneous combustion in the goaf and optimizes the ventilation scheme.

Variability of MDRO Reporting Across Tennessee Microbiology Laboratories

Background: Identification and timely reporting of multi-drug resistant organisms (MDROs) drives efficacy of infection prevention efforts. Data on MDRO reporting timeliness and inter-facility variability are limited. Facility-dependent variability in MDRO reporting across Tennessee was examined to identify opportunities for MDRO surveillance improvement. Methods: Data for reported Tennessee MDROs including carbapenem-resistant Enterobacterales (CRE), carbapenem-resistant Acinetobacter baumannii (CRAB), Carbapenem-resistant Pseudomonas aeruginosa (CRPA) and Candida auris, were obtained from the southeast regional Antibiotic Resistance Laboratory Network (ARLN) from 2018-2022, excluding screening and colonization specimens. Variance in days accrued from specimen collection to ARLN receipt was analyzed using one-way analysis of variance (ANOVA) with Tukey’s test (SAS 9.4). Facilities were categorized as fast (1-10 days), slow (11-20 days), or delayed (21-100 days) reporters. Results: There were 9,569 MDRO isolates reported. CRPA was reported faster than other MDROs (p &lt; 0.001), while specimens from West Tennessee compared to other regions (p &lt; 0.001) (Figure) and blood cultures compared to other specimens were reported more slowly (p &lt; 0.001) (Table). There was no difference in reporting times for facilities using on-site microbiology laboratories versus reference laboratories (P = 0.062). Conclusion: MDRO reporting times varied across Tennessee by region, specimen, and organism. Future work to elucidate drivers of variability will consist of surveys and focused interviews with laboratory personnel to identify shared and unique barriers and opportunities for improvement.

Evaluating the effectiveness and challenges of online laboratory practices in physical chemistry

Relevance. The COVID-19 pandemic highlighted the necessity of utilizing information technology in higher education, particularly for laboratory practices in physical chemistry. Purpose. This study aims to explore the characteristics of online laboratory practices, evaluate existing training methods, and determine the effectiveness of various approaches in laboratory instruction. Methodology. The study employed a combination of basic statistical methods and the Pearson chi-square test to analyze survey data collected from teachers and students regarding their familiarity with, interest in, and preferences for online laboratory practices. Additionally, case analysis was conducted to identify the advantages, disadvantages, and overall effectiveness of online laboratory methods used during the COVID-19 pandemic. Results. The study reveals differing preferences between teachers and students regarding laboratory practices. Most teachers (88%) favor traditional on-site laboratory work, while a significant portion of students (70%) prefer online methods. Familiarity and interest in new technological tools were assessed, showing that 94% of professors are unfamiliar with virtual laboratories, though 80% wish to learn more, and 47% actively use them. Among students, 95% are unfamiliar with virtual labs, but 88% want to learn more, and 77% see virtual labs as beneficial. Conclusions. The paper discusses challenges in integrating modern technology into physical chemistry labs and suggests that the findings could aid educators in adapting to new teaching conditions and improving educational quality monitoring. Keywords: virtual laboratory; remote learning; teaching methods; information technology; COVID-19

Space-temporal analysis of groundwater quality in three areas of the state of Yucatán, México, and its relationship with existing anthropogenic activity.

Groundwater in the Yucatan State is the only source of water. The karst aquifer in Yucatan is vulnerable to pollution. Anthropic activities in Yucatan, such as pig farming, are usually related to high wastewater discharges and water pollution. Administrative and logistical issues in developing on-site sampling to evaluate water quality are common in Mexico. The RENAMECA database provides official data related to groundwater quality. However, no analysis based on this database has been reported. A groundwater quality evaluation based on five reference pig farms and the effect of spatial and temporal anthropic activities in the study area was developed. Eighteen wells based on their location concerning the selected pig farms were studied. On-site sampling and laboratory analysis of the supply water and wastewater in the study case farm were done. Fecal coliforms (FC) values (maximum 2850 MPN [100mL] -1) in most cases for supply water wells exceeded the allowed limit by NOM-127-SAA1-2021. The year of monitoring was significant (P < 0.05) on FC concentrations. Population density and the proximity of wells to population centers affect negatively the presence of total dissolved solids (TDS) and total nitrogen (TN). TDS (maximum value 2620mg L -1) and phosphorus presence could be related to agricultural activities, human settlements, and local aquifer conditions. A local wastewater treatment issue is evident. Groundwater is not quality for consumption without treatment. Regarding the issues in on-site water monitoring, database analysis provides an approximation of the real situation of groundwater quality.

Distinct Element Method Analyses for Damage Assessment: The Northern Spur of Valverde Bulwark in the Venetian Fortress of Bergamo

ABSTRACT The 16th century Venetian Fortress, with more than 70,000 m2 of masonry wall facing, characterises the city landscape of Bergamo. Almost intact and well preserved, the defensive system was inscribed on the UNESCO World Heritage List in 2017. Today, the first causes of its deterioration are the vegetation growth and the lack of maintenance, which have led to instabilities and local failures, particularly in the northwest portion. Thus, in 2019 and 2020, survey campaigns were carried out to assess the safety of one of the most damaged sections, the Valverde bulwark. The survey combines on-site observations, laboratory tests, and photogrammetric and laser scanner surveys to describe the bulwark. Numerical simulations have been performed using a distinct element approach, i.e. assimilating the masonry to a system of discrete bodies consisting of blocks (usually rigid) interacting on their interfaces. A routine dedicated to defining a real-like geometrical model has been developed. The numerical analyses were run to assess the conditions of the Valverde bulwark under self-weight and earth pressure and considering seismic load. Through the detailed survey and its automatic digitisation, it is possible to fully recognise and analyse the state of health of these historic structures and their mechanical behaviour.

A comparative analysis of corrosion assessment techniques for steel in reinforced concrete exposed to brine water environments

Abstract Corrosion assessment of steel-reinforced concrete specimens submerged in synthetic brine water with various chloride concentrations for 1–16 weeks was performed. Mass loss measurements combined with electrochemical techniques – half-cell potential, linear polarization (LP), and electrochemical impedance spectroscopy (EIS) – were employed. The results obtained from all corrosion assessments – on-site testing (half-cell potential measurements), laboratory scale (LP and EIS measurements), and destructive testing (mass loss or immersion measurements) – exhibited remarkable consistency, complementarity, and mutual supportiveness. Corrosion rate (CR) values from mass loss were close to those obtained from LP and EIS. The corrosion resistance decreased with increasing chloride concentration and immersion time, as indicated by the highest CR, Ca2+, and Fe2+ concentrations, and the lowest half-cell potential and polarization resistance. X-ray photoelectron spectroscopy investigation on the corroded steel surface revealed Fe(III) oxides and hydroxides and Fe(III) (FeCl3), corresponding to the reduction in polarization resistance in the LP and EIS results.

Life cycle assessment of iron-biomass supported catalyst for Fischer Tropsch synthesis.

The iron-based biomass-supported catalyst has been used for Fischer-Tropsch synthesis (FTS). However, there is no study regarding the life cycle assessment (LCA) of biomass-supported iron catalysts published in the literature. This study discusses a biomass-supported iron catalyst's LCA for the conversion of syngas into a liquid fuel product. The waste biomass is one of the source of activated carbon (AC), and it has been used as a support for the catalyst. The FTS reactions are carried out in the fixed-bed reactor at low or high temperatures. The use of promoters in the preparation of catalysts usually enhances C5+ production. In this study, the collection of precise data from on-site laboratory conditions is of utmost importance to ensure the credibility and validity of the study's outcomes. The environmental impact assessment modeling was carried out using the OpenLCA 1.10.3 software. The LCA results reveals that the synthesis process of iron-based biomass supported catalyst yields a total impact score in terms of global warming potential (GWP) of 1.235E + 01kg CO2 equivalent. Within this process, the AC stage contributes 52% to the overall GWP, while the preparation stage for the catalyst precursor contributes 48%. The comprehensive evaluation of the iron-based biomass supported catalyst's impact score in terms of human toxicity reveals a total score of 1.98E-02kg 1,4-dichlorobenzene (1,4-DB) equivalent.

An Evaluation of the Tuberculosis Prevention and Care Program in Gweru District, 2022: The Need to Increase Bacteriological Coverage

Introduction: Tuberculosis remains a disease of public health concern. The national TB program has onsite laboratories (with Gene Xpert and CXR services) and is supported by a partner with mobile screening trucks that are equipped with the same equipment.

Perceived Skill Gaps among Students Due to Reduced Onsite Laboratory Activity

This study investigates skill gaps in the College of International Tourism and Hospitality Management due to reduced onsite laboratory classes during the COVID-19 pandemic. Significant correlations reveal interventions needed in specific courses, while students in Tourism Management report positive responses to virtual learning opportunities. Data from 65 respondents were gathered using a researcher-made survey. Descriptive methods and statistical analyses, including weighted mean and Pearson correlation, were employed to examine the research objectives. The study emphasizes the importance of hands-on experiential learning in Tourism and Hospitality programs and proposes guidelines to address skill gaps effectively. Further research is recommended to support identified gaps, expand to other programs, enhance guidelines, and explore technology for remote laboratory activities. Key Words: COVID-19, Online classes, Distance Learning, Laboratory, Instruction, perceptions of online learning, education during COVID-19, blended learning, Hospitality Education

The management of transformed small river basins of Volyn Polissia – Buniv River case study

The assessment of the transformation level in the Buniv River basin (Ukraine) transformation was performed. Substantiates the need to improve the monitoring system within the river basin, as the main tool for assessing and predicting changes in the aquatic ecosystem and managing the processes of its anthropogenic. The research methods included on-site investigations, laboratory and analytical studies, data processing using GIS technologies. A topographic survey of the Buniv River’s floodplain within the village of Rokytne town was performed. The on-site investigations included field surveys and water sampling at 4 control sites on the Buniv River for 13 quality indicators. The analysis of the obtained cartographic models indicates a significant anthropogenic transformation of the natural landscapes. A significant part of the watercourses of the Buniv River basin was once directed and transformed into main canals of the meliorative systems. This causes the formation more dangerous flood flow.

Selectivity of MOFs and Silica Nanoparticles in CO2 Capture from Flue Gases.

Until reaching climate neutrality by attaining the EU 2050 level, the current levels of CO2 must be mitigated through the research and development of resilient technologies. This research explored potential approaches to lower CO2 emissions resulting from combustion fossil fuels in power plant furnaces. Different nanomaterials (MOFs versus silica nanoparticles) were used in this context to compare their effectiveness to mitigate GHG emissions. Porous materials known as metal-organic frameworks (MOFs) are frequently employed in sustainable CO2 management for selective adsorption and separation. Understanding the underlying mechanism is difficult due to their textural characteristics, the presence of functional groups and the variation in technological parameters (temperature and pressure) during CO2-selective adsorption. A silica-based nanomaterial was also employed in comparison. To systematically map CO2 adsorption as a function of the textural and compositional features of the nanomaterials and the process parameters set to a column-reactor system (CRS), 160 data points were collected for the current investigation. Different scenarios, as a function of P (bar) or as a function of T (K), were designed based on assumptions, 1 and 5 vs. 1-10 (bar) and 313.15 and 373.15 vs. 313.15-423.15 (K), where the regression analyses through Pearson coefficients of 0.92-0.95, coefficients of determination of 0.87-0.90 and p-values < 0.05, on predictive and on-site laboratory data, confirmed the performances of the CRS.

Quantifying Dense Multicomponent Slurries with In-Line ATR-FTIR and Raman Spectroscopies: A Hanford Case Study.

The multiphase nature of slurries can make them difficult to process and monitor in real time. For example, the nuclear waste slurries present at the Hanford site in Washington State are multicomponent, multiphase, and inhomogeneous. Current analytical techniques for analyzing radioactive waste at Hanford rely on laboratory results from an on-site analytical laboratory, which can delay processing speed and create exposure risks for workers. However, in-line probes can provide an alternative route to collect the necessary composition information. In the present work, Raman spectroscopy and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy are tested on simulants of nuclear waste slurries containing up to 23.2 wt % solids. We observe ATR-FTIR spectroscopy to be effective in measuring the solution phase of the studied slurry systems (3.52% mean percent error), while Raman spectroscopy provides information about the suspended solids in the slurry system (18.21% mean percent error). In-line measurement of multicomponent solids typical of nuclear waste processing has been previously unreported. The composition of both the solution and solid phases is vital in ensuring stable glass formulation and effective disposal of nuclear waste at Hanford. Raman and ATR-FTIR spectroscopies can provide a safer and faster alternative for acquiring compositional information on nuclear waste slurries.

Permeability Tests and Numerical Simulation of Argillaceous Dolomite in the Jurong Pumped-Storage Power Station, China

Due to its poor hydro-physical properties and other characteristics, argillaceous dolomite is susceptible to seepage failure under high water pressure, affecting the seepage stability of a rock mass. To ensure the safety of the project, when the argillaceous dolomite is present, it is necessary to study the conditions pertaining to its seepage failure. Taking the argillaceous dolomite of Jurong Pumped Storage Power Station as the research object, the spatial distribution, occurrence, scale, degree of weathering, and mechanical and hydrogeological characteristics of the argillaceous dolomite were studied. Through on-site water pressure tests and laboratory variable head tests, the permeability characteristics of argillaceous dolomite were analyzed, and the hydraulic conductivity of the argillaceous dolomite in the upper reservoir and underground powerhouse areas was quantified. The argillaceous dolomite specimens were collected, and seepage failure tests were conducted to determine the critical water pressure for its seepage failure. Based on the results of the laboratory tests, a numerical model of groundwater flow was established. By changing the water level of the upper reservoir and the measures of the anti-seepage and drainage, the seepage stability of the argillaceous dolomite was discussed. The actual water pressure of argillaceous dolomite in the underground powerhouse area was identified during the operation of the Jurong pumped-storage power station. The calculations show that when fully enclosed anti-seepage and drainage measures are taken for the underground powerhouse, the maximum head of water is 98 m, which is lower than the critical water pressure of seepage failure for the argillaceous dolomite. Therefore, no seepage failure will occur. The results provide a scientific basis for the anti-seepage and drainage design of the underground powerhouse area.