Soil-based onsite wastewater treatment systems (OWTS) are becoming more important for the treatment and disposal of wastewater in areas that do not have central wastewater collection and treatment systems. However, there are concerns that OWTS may have adverse effects on public health and environment. The purpose of this study is to treat wastewater using a natural soil column in order to evaluate treatment system performance. Wastewater was applied to two different natural soils at different flow rates of 9, 18 and 36 L/day. The treatment performances of wastewater and geotechnical properties of the natural soils were examined. As a result of this study, the percentage of COD and SS removal in wastewater after soil column filtration ranged from 36.2% to 80.5% and 84.4% to 97.9% respectively. pH values of wastewater after the filtration were measured at between 7.75 and 8.12. TP and TN removal rates were found in the range of 23.9–76.8% and 12.4–83.0%, respectively. The column effluent water was classified as both ‘high hardness class’ in terms of hardness and ‘polluted water’ in terms of conductivity. Column effluent water was found in ‘low, medium, and high hazard’ classes in terms of SAR. Whereas the PL values of the natural soils were found to increase by up to 4.8% in the filtration area, specific gravity decreased by nearly 1.1%. The values of LL, PI, maximum dry density, optimum water content, and permeability changed depending on the soil type. The UCS of the natural soils after wastewater filtration decreased by about 5.9%. It was concluded that natural soils have positive effects on treatment of wastewater in a short time.

The construction sector is known to have the highest risks of occupational accidents. A rationale for this high occurrence of occupational risks can be related to legislative requirements to enforce safe construction practices within this sector. Within the context of excavation works in Turkey, this study investigates the leading risks for any compliance shortfalls and ultimately presents recommendations to mitigate occupational accidents’ occurrences during excavation works in the construction sector. Based on a quantitative methodology, a closed-ended survey consisting of 35 questions and based on legislative requirements was applied to project managers in the construction industry, such as site supervisors, occupational safety experts, auditors, and control personnel. A sample size of 277 responses was found to have stability and validity through a reliability analysis and an exploratory factor analysis, and was used for testing statistical significance via cross-tabulation analysis and chi-square tests. The findings revealed that the major deviation of safety in excavation works from legislative requirements is executing works during adverse weather conditions. Moreover, it was also noteworthy that protective curtains did not surround the excavation sites, and most of the employees encountered ground slippage during excavation work. Therefore, the findings revealed preliminary research that will contribute positively to providing incentives for a focus on and development of relevant security and technical measures. It also provided information to protect the safety and welfare of the workers involved in excavation works. Finally, though these findings may be considered context-specific, this research can be used for comparative purposes for similar studies into the safety practices of excavation works in different countries, where generalized findings can be later derived to inform academia and practice.

Bu çalışmada yeni hizmete alınan bir kamu idari hizmet binasının mühendislik özellikleri biyoharmoloji bilimi kapsamında incelenmiş ve Biyoharmolojik Uygunluk Değeri (BUD) belirlenmiştir. Binanın incelemesi 26-27 Mart 2018 tarihlerinde yapılmıştır. Bina incelemesinde toplam 14 mühendislik özellikleri ve kriterleri ele alınmıştır. Yapılan BUD inceleme çalışması sonucunda daha yeni tamamlanan ve hizmete alınan binanın “İyileştirilmeli” sınıfında ve minör değişikliklere ihtiyacı olduğu anlaşılmıştır. Binanın BUD puanı ~434 olarak hesaplanmıştır. Ayrıca binanın eksiklik ve yetersizlik değeri %32'dir. Binada belirlenen en zayıf ilk üç mühendislik özellik “Mekanik Sistem”, “Tefrişat ve Düzenleme” ve “Aydınlatma” şeklindedir. Diğer taraftan binanın en iyi ilk üç mühendislik özelliği ise “Taşıyıcı Elemanlar”, “Sismoloji” ve “Kullanıcı Kimliği”dir.