Vehicle Operating Costs (VOC) refer to the expenses incurred by entrepreneurs/ operators in manage public transportation in a year. The ‘Recealed Pteference’ method is used to determine VOC by conducting a survey based on field conditins. This research aims to determinethe VOC on rural public transport on the Letta-Bungi route and compare the applicable transport rates with the VOC analysis results. It also aims to find out how much income is generated by rural public transportation busineses operating on the Letta-Bungi route. The research employs a quantitative survey method and analysis data using formulas, literature, journals and previous research. The analysis of Vehicle Operational Costs (VOC) for rural public transport on Letta-Bungi route in Pinrag Regency was conducted. For an annual mileage of 11,160 km/year and an average speed of 30 km/hour. According to the analiysis, the yearly operating cost of the vehilcs is IDR 232.956.075,- and the Operating Cost per km is IDR 20.874.20,-. The current tariff of IDR 50.000,-/pnp is higher than the calculated tariff of IDR 42.443,-/pnp. The study analysis also shows that the profits obtained by business operators amount to IDR 55.043,925,-/year and IDR 4.932,25,-/km.

This research was conducted in Slango village, Sarolangun Regency, Jambi. This research focuses on analyzing the source of rock origin, namely sandstone found in the Peneta Formation. Sandstone in the study area is quite widely distributed with varied characteristics, so determining the original rock is easy to do. This research was carried out to identify the origin of the rock through petrographic analysis of the sandstone so that the history of the formation of the Peneta Formation itself can be reconstructed. After provenance analysis, the Peneta Formation sandstone comes from the Recycle Orogen, precisely in the Subduction Complex Sources subzone. Apart from that, the Peneta sandstone also shows the origin of the Magmatic Arc. Thus, it is interpreted that the Peneta Formation sandstone has undergone several uplift processes due to tectonic activity and has experienced increased maturity or stability from the Continental Block Provenances. Apart from that, it is also influenced by the weathering process of granite heights or other volcanic materials, whether volcanic or plutonic. Key words: Sandstone, Slango Village, Peneta Formation, Petrography, Provenance

When welding, you don't have to connect two metal materials, you can also weld the thickness of the component. Steel is a metal material that can be used in the engineering field to make alloys of other metals so that they can have better material properties than the original metal material. One thing that can be done to increase resistance to wear is to increase the surface hardness of the workpiece. This research carried out an analysis to increase the hardness of the surface of low carbon steel after heat treatment for 60 minutes with variations in quenching media resulting from hardfacing using SMAW welding (shield metal arc welding) with DC+ and DC- polarities. The data analysis technique used in this research is specimen testing. The results obtained later by the research show that DC+ polarity has higher hardness in all specimens tested with a value of 418.66 VHN water quenching, 402.8 VHN oil quenching, 348 VHN non-treatment when compared with DC- polarity with a value of 405, 92 VHN quenching water, 374.02 VHN quenching oil and 323.38 VHN non-treatment. Quenching media with water obtained the highest hardness results with a value of 405.92 VHN.

In line with the concept of environmentally friendly national development, every commercial and industrial activity must be committed to preserving the environment. This is in accordance with Law no. Regulation Number 32 of 2009 concerning Environmental Protection and Management. Referring to Law No.30 of 2007 concerning Energy, which was then followed up with Government Regulation No.33 of 2023 concerning Energy conservation which requires energy users above TOE to carry out Energy conservation by conducting periodic Energy Audits of Lighting Systems and Air Conditioning Systems . This research conducted an audit of lighting and air conditioning systems by collecting data on lighting intensity, temperature and humidity in each room in the office from 08.00 – 17.00 using a lux meter measuring instrument, then the results were analyzed by referring to the Indonesian National Standards (SNI) regarding lighting and Minister of Energy and Mineral Resources Regulation No. 13 of 2012 concerning Saving on Electricity Use. The use of electrical energy in the office work environment is still not optimal and even though the density value is satisfactory, the lighting level in the office still has rooms that do not meet SNI standards. Apart from that, the use of electrical energy for the air conditioning system is also considered insufficient so several recommendations need to be made

Sustainability Development is one of the target to be achieved in order to maintain the sustainability of future generations without reducing the needs of present. One form of sustainable development that is implemented is green building certification to assess the level of efficiency savings that have been made. This study aiming to analyze the application of green building concept in office buildings. Application analysis was carried on on energy, water, and material efficiency aspects using EDGE program issued by IFC (International Finance Coporation) which is ne of the poviders green building certification. The scope used in this study is that this assessment is carried out with the aim of certifiying exsisting building and post construction. Based on the analysis results, it is known that the value of green building implemtation in office building is 16,63% energy savingi, 34,79% water savings dan 92% material savings

In the wastewater industry, it is divided into 2, specifically wastewater from home activities and production. Domestic activity wastewater comes from all worker sanitation activities and industrial supporting facilities such as prayer rooms, canteens and toilets. Waste water from these activities must be treated first so that it does not pollute the surrounding environment. PT X is an industry that operates in the field of bulk LPG filling stations which has made efforts to process and also utilize 100% of the waste water from its domestic activities. Sewage Treatment Plants handle the processing (STP) facilities with chemical and biological processes which are able to reduce pollutant parameters such as BOD, COD, TSS, Ammonia and Total Coliform by 90%, 85%, 95%, 90% and 99.9% and have been meet the specified quality standards. Meanwhile, oil & fat parameters are not too focused because they still meet existing quality standards, Therefore, processing aims to lower the relatively high organic characteristics. The results of this processing will be reused to reduce the use of clean water for irrigating green open spaces and roads.

The fabric printing industry makes a major contribution to various kinds of textile products, its by-products, liquid waste, require special attention in environmental management. Most of the liquid waste originating from the fabric printing industry consists of dyes, solvents and other processing chemicals. To prevent negative effects on water quality and the surrounding environment, managing this waste is very important. To achieve sustainability, advances in liquid waste processing technology are very important. The solution to reduce the impact of liquid waste from the fabric printing industry is an advanced purification process. PT. X to reduce polutan parameter such BOD, COD , TSS, Ammonia and Total Colidform by. 90%, 95%, 95%, 85%, 20%, 90% And meets the specified quality standards. Because the pH parameters still meet existing quality standards, processing is focused on reducing the organic parameters which are quite high. The results of the process will be used again for flushing activities in green open spaces and for washing operational vehicles.

The importance of K3 aspects in docking activities not only includes individual safety, but also has a direct impact on productivity and operational continuity. Accidents or incidents that occur during the docking process can not only threaten the lives and health of workers, but can also cause detrimental environmental impacts and hinder the smooth running of the supply chain. The HIRARC method allows identifying various potential hazards that may be associated with an activity or work environment. This approach involves data collection, situational analysis, and determining appropriate mitigation measures. From the results of the identification carried out during ship docking activities at PT. Pelindo Marine Service has 14 activities that have potential danger. With 4 activities that have very low risk, namely maintenance and repair activities in the engine room, ship maintenance in closed rooms, maintenance and repairs in the electrical room, and manual lifting of heavy materials. Then there are 5 activities with low risk, including welding process activities in open spaces, carrying out repair work at height, operating cranes, cleaning ship rooms, and plate cutting (LPG gas cutting) and material grinding processes. 3 activities with medium/medium risk, namely working around waters, working/standing around ships, and stuffing/stripping activities. And there is 1 activity with high risk, namely the ship maintenance process using the welding process in a closed space and 1 activity with very high risk, namely the activity of filling gas cylinders (for cutting and welding equipment). The risks faced include slipping, falling, scratches, shortness of breath, weakness, eye irritation, injuries, minor injuries, serious injuries, sprains, burns, fractures, electrocution and others. And the efforts made to control the risks above include using Personal Protective Equipment with discipline, working according to SOPs, installing K3 signs, providing fire extinguishers, regular inspections and implementing a good ventilation system. Based on the results of risk identification in ship docking activities at PT. Pelindo Marine Services. The importance of effective and continuous implementation of K3 in ship docking activities, in order to maintain the safety, health and welfare of workers and minimize negative impacts on company operations

Lamong Bay is one of the important water areas in Indonesia, located around the coastal area of ​​Surabaya, East Java. This area has high ecological and economic value because it functions as a sea transportation route and supports marine biota. So this research is intended to monitor the quality of sea water in Lamong Bay based on benthos and plankton bioindicators. Plankton and benthos are small organisms that live in waters and are very sensitive to environmental changes. The plankton sampling method involves using a plankton net to collect plankton samples from the waters. The grab and net sampling method is a method used to collect benthos samples from the bottom of the waters. The results that can be concluded from the analysis carried out in the waters of Lamong Bay, for the type and abundance of plankton, phytoplankton are 3 classes, namely Bacillariophyta (16 species), Cyanobacteria (2 species), and Euglenozoa (1 species), and zooplankton found include Arthropods Monacilla sp. and Nauplius, Ciliophora individuals include Favella sp. , Tintinnopsis sp. , Tintinnopsis sp. 2, Tintinnopsis sp. 3 as well as individual Rotifera including Notholca sp. Meanwhile, for Benthos, only Thiaridae was found.