Compared with the water-base drilling fluid, oil-based drilling fluid has always been one of the important technical guarantees in high temperature deep well, high-inclination directional well and all kinds of complex seismic exploration. With 5#white oil selected and taken as continuous phase, emulsifying agent, organic soil, tackifier, fluid loss agent, lime, other treatment agents and dosages are optimized and the optimal formula of oil-base drilling fluid is determined. This new type environmentally-friendly oil-base drilling fluid possesses good rheological properties, suspension capability, high temperature stability, stronger anti-pollution ability and common emulsion-breaking voltage of more than 2000 V. During the field application, this fluid possesses regular borehole diameter, good lubricity, stable borehole, simple preparation process, easy site maintenance and good reservoir protection features. Furthermore, it can solve complex formation, water expansion of clay shale, poor lubrication & drag reduction effect, poor reservoir protection effect and other technically-difficult problems.

Ezine Stream Watershed, located in the Black Sea Region, Kastamonu, T & uuml;rkiye, is a flood-prone area. A devastating flood occurred on August 11, 2021, causing 70 fatalities and considerable damage to structures along the stream channel. In this study, a hydrodynamic model of the watershed was developed using the Environmental Protection Agency's Storm Water Management Model (EPA SWMM). The main channel and floodplain were simultaneously modeled utilizing the 'irregular channel' option in SWMM. The model was calibrated and verified using historical precipitation and discharge data. The validity was further evaluated by comparing outputs with observations from photos and videos taken on-site by local authorities and residents during the flood. The model was manually calibrated focusing on optimizing depression storage, soil drying time, curve number, and roughness coefficients for the channels and subcatchments. The model results served as the basis for implementing flood control strategies. Three scenarios were proposed for flood mitigation: the implementation of a newly designed improved channel, the construction of a flood control dam, and the installation of 15 check dams. The flood mitigation effectiveness of each scenario was assessed, and a thorough analysis was conducted to determine the optimal choice for the region. Consequently, each scenario played a significant role in reducing the peak flow rate. Among these scenarios, the flood control dam demonstrated the most substantial impact on reducing the flood flow. This study offers beneficial findings to the decision-makers on flood control planning in the watershed and contributes to future research in the field.

In the study, JL-BC, an environmentally friendly shale inhibitor with a temperature tolerance of 220 degrees C was synthesized by grafting modified nano biochar (BC) onto polyarginyl lysine (JL) for the first time. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric (TGA) tests indicated that JL-BC had been successfully synthesized and had good thermal stability. The inhibition performance of JL-BC was experimentally evaluated by linear swelling test, hot-rolling recovery test and sodium bentonite (Na-BT) block immersion test, and the inhibition mechanism of JL-BC was studied by various experimental characterization methods. The experimental results showed that compared with potassium chloride (KCl), polyether amine (PEA), bionic inhibitor dopamine (DA), 2, 3-epoxypropyltrimethylammonium chloride (EPTAC), and poly dimethyl diallyl ammonium chloride (PDMDAAC), Na-BT had the lowest linear swelling height of 4.49 mm in 4 % JL-BC solution at 150 degrees C. The recovery rates of shale cuttings were highest in 4 % JL-BC solution at 200 degrees C and 220 degrees C, which were 96 % and 92 %, respectively. The Na-BT block was immersed in 4 % JL-BC solution for 16 h basically retained its original morphology. The excellent inhibition performance of JL-BC was mainly attributed to the positive charge of JL-BC in aqueous solution at pH 9, which was strongly adsorbed on Na-BT, lowering the zeta potential of Na-BT, destabilizing Na-BT and causing it to aggregate. With the increase of JL-BC concentration, NaBT gradually aggregated into larger flocs, increasing the particle size of Na-BT. Nano BC reduced water intrusion to a certain extent by physically blocking micropores. In addition, the EC50 value of JL-BC was 2.93 x 105 mg/L, indicating that it was non-toxic. The addition of JL-BC to the soil effectively increased the content of organic matter, ammonium nitrogen and available potassium, and promoted the growth of wheat seedlings. This work may open a new avenue for the development and use of environmentally friendly treatment agents.

Phosphogypsum, which contains toxic components (e.g., heavy metal elements and fluoride), is one of the byproducts of phosphoric acid production, and filling subgrade is one of the recycling methods for it. In this study, phosphogypsum was stabilized by lime to improve the mechanical properties [California bearing ratio (CBR), resilience modulus, unconfined compressive strength, and shear strength], water stability, and harmful substances dissolubility. Combined with scanning electron microscopy, the strength formation and water stability enhancement mechanism of lime-stabilized phosphogypsum (LSP) were explored. The results demonstrated that the mechanical properties of LSP were better with the lime content of 6%-10%. The CBR, resilience modulus, unconfined compressive strength, and shear strength were 3.35 times, 2.46 times, 8.61 times, and 1.39 times that of plain phosphogypsum, respectively. An intensity prediction model with a correlation of 97% was constructed. The CBR and resilience modulus softening coefficient of LSP reached best values when lime content was 6%-8%. The leaching concentration of arsenic, chromium, and lead of LSP with 2% lime met the quality standards of groundwater levels I, II, and IV, respectively. Fluoride and phosphate were not detected in LSP when lime content was greater than 6.0%. The results show that LSP is feasible as subgrade filler. Considering the mechanical properties, water stability, and dissolution of hazardous substances of LSP, it is recommended to add 6%-8% lime content to LSP as highway subgrade filler.

Challenges related to sustainability arise in all areas of human activity, but with a significant impact on the environment considering that the construction industry is held accountable for nearly one-third of the world's final energy consumption. The aim of this paper is to assess through the use of the Bob-Dencsak specific model a sustainable slope design taking into account environmental, economic, and safety variables. Thus, analysis was performed on four intervention works, two versions of reinforced concrete retaining walls and two versions of reinforced soil with a biaxial geogrid, which ensure the stability of a slope that serves as a base for an access road to an ecological landfill located in Alba County, Romania. The study's analysis points out that reinforced soil retaining walls are far more sustainable, providing the best sustainability indices, which is also supported by the impact of geogrids compared to reinforced concrete, thus resulting in the finding that reinforced concrete is less sustainable, achieving increases of up to 23% for embodied energy and 66% of CO2 emissions in the atmosphere. Finally, the paper provides recommendations for future research on the sustainability assessment of slopes, with the intention of reducing environmental damage, while keeping costs to a minimum.

Radon is a naturally occurring radioactive gas found in rocks, soil, and building materials. Precisely because of its gaseous nature, it tends to concentrate in indoor environments, resulting in a danger to human health. The effects of radon have been described, documented, and attested by the international scientific community and recognized as the second cause of lung cancer after cigarette smoking and in synergy with it. In December 2013, the Council of the European Union issued Council Directive 2013/59/Euratom, which establishes basic safety standards relating to protection against the dangers deriving from exposure to ionized radiation and managing the health risks associated with radon. In addition, designing buildings against radon risk in synergy with the use of low environmental impact materials is one of the objectives of building sustainability certifications. This work presents how radon creeps into buildings and reports several technologies that are needed to remove and mitigate the risk associated with indoor radon in existing and new buildings.

Environmental Impact Assessment (EIA) became mandatory in Pakistan in 1983 with the passage of the Pakistan Environmental Protection Ordinance. The Sustainable Development Goals were incorporated into Pakistan's national development strategy, making it the first country in history to do so. The study is based on evaluating the mitigation strategies and environmental impact assessment at the Gulpur Hydropower Project (HPP), Kotli, AJK, which uses the Poonch River's water resources to generate power and has a design capacity of 100 MW using the EIA documentation of Gulpur HPP. In addition to making additional observations and reviewing the literature, the study looked at Mira Power Limited's EIA reports. The possible effects, as well as the Government's and MPL's mitigating actions, were examined by the authors. EIA procedures at the Gulpur HPP considered several laws, including the Pakistan Environmental Protection Agency, AJK Wildlife Ordinance of 2013, the Land Acquisition Act of 1894, and Laws Regulating Flow Releases for Hydropower Projects. Projects using hydropower in delicate areas carry a high risk. Given the thorough analysis of the hazards in this instance, it is evident that the EIA had a significant impact on the project's design. The authors concluded that there are no negative environmental effects of the construction of hydropower projects in the concerned area and that all potential effects and compensation were handled legally and efficiently. The study suggested that all hydropower projects in Pakistan undertake environmental impact assessments. Evaluating the mitigation strategies and environmental impact assessment at the Gulpur Hydropower Project.EIA procedures at the Gulpur HPP considered several laws, including the Pakistan Environmental Protection Agency.The development of hydropower projects in the affected area had no negative environmental effects, and any potential effects or compensation were handled lawfully and effectively.