Envirotek : Jurnal Ilmiah Teknik Lingkungan

Optimization of Household Organic Waste Composting Using the Biopot Composting Method and Rice Washing Water as a Starter Culture

Devi Kurnia Sari — 2026-10-30

Household organic waste management in Sungai Langka Village was implemented using the biopot composting method combined with rice-washing water as a starter culture. Organic waste was collected at 08:00 WIB from two hamlets: Hamlet 1, consisting of 7 households, generated 8.45 kg/day, while Hamlet 2, consisting of 5 households, generated 7.25 kg/day, resulting in 15.7 kg/day from 12 households. This study aimed to identify the composition of household organic waste, analyze the physical and chemical characteristics of the compost, and determine the percentage of organic waste reduction. Each biopot pipe was filled with 1 kg of organic waste under four treatments: P0 without starter culture, P1 with 100 ml, P2 with 200 ml, and P3 with 300 ml of rice-washing water starter culture. Composting was conducted for 31 days based on maturity indicators, including temperature stabilization, near-neutral pH, dark color, earthy odor, and waste reduction. The results showed that starter culture dosage influenced composting performance. P2 showed the best overall descriptive performance, with the highest waste reduction of 76% and favorable compost characteristics. Most parameters met SNI 19-7030-2004 and SNI 7763:2024, although moisture content required further drying or curing

Fish Waste Management Model in Fishermen Settlements to Support Coastal Environmental Resilience

Vissia Poppy Puspita Lestari — 2026-10-30

Fish processing activities in fishermen settlements generate solid and liquid waste that may cause environmental pollution if not properly managed. Therefore, an appropriate waste management system is required to minimize environmental impacts while supporting coastal environmental resilience. This study aims to analyze the fish waste management system in fishermen settlements and develop a community-based waste management model to improve environmental quality in coastal residential areas.

This study employed a descriptive qualitative approach through field observations and literature analysis to identify waste types and their potential utilization. The results show that fish processing activities produce solid waste, such as fish heads, bones, and skin, as well as liquid waste from fish washing processes. Solid waste can be utilized as fish meal, animal feed, and organic fertilizer, while liquid waste can be treated through simple systems such as sedimentation ponds and biofilters before discharge into the environment.

The proposed model integrates waste segregation, waste treatment, and resource utilization. The model is expected to improve environmental quality, strengthen coastal environmental resilience, provide economic benefits for coastal communities, and support the achievement of Sustainable Development Goal 11 related to sustainable cities and communities.

Structural Control on Interpreted Subsurface River Flow Patterns in a Karst Landscape: A Case Study of the Bekah Area, Purwosari, Gunungkidul, Yogyakarta

Nandra Eko Nugroho — 2026-10-30

The Bekah karst area in Purwosari, Gunungkidul, Yogyakarta, is part of the Pegunungan Sewu karst landscape, where groundwater availability is closely related to subsurface river systems. This study investigates structural control on interpreted subsurface river-flow patterns using integrated geological, geomorphological, and Very Low Frequency Electromagnetic (VLF-EM) approaches. Field mapping was conducted to identify lithology, karst landforms, faults, joints, fractures, lineaments, and cave-related features. VLF-EM data were acquired along six west–east survey lines, with line lengths of approximately 540–800 m and a station spacing of 20 m. The data were processed into equivalent current density (ECD) sections to detect conductive subsurface anomalies. The results show that the dominant structural trend is northeast–southwest, corresponding with valley orientation, lineament patterns, and several high-conductivity anomalies. These anomalies occur mainly at approximate depths of 20–100 m, with a deeper response reaching about 140 m along Line 4. The anomalies are interpreted as potential water-bearing zones, saturated fractures, or structurally controlled subsurface drainage pathways. The findings indicate that subsurface drainage in the Bekah karst area is likely influenced by fault and fracture systems rather than lithology alone.

Potential of Microbial Consortia (Bacteria-Fungi) in Hydrocarbon-Contaminated Soil Bioremediation: Overcoming Wax Fraction Degradation Challenges

Fikri Daryat — 2026-10-30

Soil contamination by petroleum hydrocarbons, including wax fractions, is a major global environmental issue causing ecosystem degradation, decreased soil fertility levels and effects on human health. Conventional physical-chemical remediation techniques are often costly and unsustainable. Alternatively, the application of bacterial-fungal microbial consortia has emerged as a promising bioremediation solution. This consortium offers superior metabolic synergy to break down complex hydrocarbons, facilitated by the production of biosurfactants and extracellular enzymes. This review article focuses on the potential of bacterial-fungal consortia in remediating hydrocarbon-contaminated soils, addressing aerobic and anaerobic degradation, biosurfactant performance and the challenges of degrading wax fractions. The review concludes that further research is essential to optimize the use of bacterial-fungal consortia for degrading wax fractions in heavy oil-polluted soils, leading to the development of viable bioremediation technologies

Bridging Technology and Tradition: A Review of IoT-Based and Local Wisdom-Based Early Warning Systems in Indonesia

Sisil Desi Pratiwi — 2026-10-30

Indonesia is highly vulnerable to geological and hydrometeorological hazards. The Early Warning System (EWS) has become a key strategy in disaster mitigation, which is now evolving towards the use of Internet of Things (IoT) technology as well as integration with local wisdom. This study aims to review the implementation, characteristics, and reported outcomes of IoT-based and local wisdom-based early warning systems for disaster risk reduction in Indonesia. A systematic literature review was conducted by analyzing 20 scientific articles published between 2020 and 2024. The reviewed studies indicate that IoT-based early warning systems commonly enable real-time monitoring, automated hazard detection, and rapid information transmission for measurable hazards such as floods and earthquakes. . Meanwhile, EWS based on local wisdom is more contextual and sustainable, able to reach remote areas and strengthen socio-cultural resilience. The two approaches have complementary characteristics that may strengthen the effectiveness of disaster-risk reduction., thereby increasing the effectiveness of disaster risk mitigation holistically. This study recommends the integration of IoT-EWS and local wisdom in national policies and disaster education to strengthen community resilience in various regions.

Fabrication and Performance Evaluation of PVDF/Nano-TiO₂ Membrane via NIPS Method for Tetracycline Removal Using Vacuum Filtration.

Ayutri Suryana — 2026-10-30

Water pollution caused by tetracycline contamination is a serious issue due to its poor biodegradability and potential to trigger antimicrobial resistance. This study aims to evaluate the filtration performance (permeate flux and rejection efficiency) of a PVDF membrane modified with 10% nano-TiO₂ fabricated via non-solvent induced phase separation (NIPS) under vacuum filtration for tetracycline removal. Polyvinylidene fluoride (PVDF) membranes modified with 10% (wt) nano-TiO₂ were cast using the NIPS method and processed using a vacuum filtration system at 200 mbar. The incorporation of nano-TiO₂ may improve membrane hydrophilicity and pore formation, as indicated by SEM morphological changes and supported by previous studies. The morphology exhibits a distinct asymmetric structure, consisting of a thin, dense upper layer and a lower layer dominated by sponge-like pore structures. The modified membrane demonstrated a very high permeate flux ranging from 312.5 to 8,375.2 L·m⁻²·h⁻¹·bar⁻¹, while tetracycline rejection ranged from 29.31% to 55.81%. The high flow rate indicates that the system can manage wastewater contaminants on a large scale. However, further optimization of the molecular sieve separation system is required to improve rejection. Overall, PVDF modification with nano-TiO₂ has proven effective in boosting filtration productivity and holds potential for treating tetracycline-contaminated wastewater.

NaOH-Activated Fly Ash Adsorbent in Copper(II) Metal Ion Removal from Laboratory Wastewater

Muhammad F. A. Khairullah — 2026-10-30

The discharge of untreated laboratory wastewater containing highly toxic copper(II) poses a significant environmental risk, highlighting the need for an effective and low-cost treatment material. At the same time, the accumulation of coal fly ash from Indonesia’s electricity sector requires sustainable waste valorization strategies. Addressing these dual environmental challenges, this study proposes a 'waste-to-treat-waste' approach by evaluating NaOHactivated fly ash (FA-NaOH) to reduce copper(II) ion levels in laboratory wastewater. FTIR characterization of FA-NaOH identified functional groups including –OH, Si–O, and Al–O, which are responsible for metal ion binding. Adsorption experiments using a copper(II) model solution determined the optimum operating conditions. The optimum adsorbent dosage was 2 g per 100 mL with a contact time of 60 minutes, achieving 99.07% copper(II) removal. Application of the optimized conditions to actual laboratory wastewater achieved 77.10% removal. The lower efficiency indicates the influence of competing heavy metals and other constituents in the wastewater matrix. Although FA-NaOH effectively lowers copper(II) levels, the treated wastewater did not fully comply with regulatory requirements. Therefore, additional pretreatment is recommended to enhance adsorption performance. These findings demonstrate the potential of FA-NaOH as an effective alternative adsorbent for heavy metal removal from laboratory wastewater.

Assessment of Wastewater Pollution Levels from the Laboratory Building and Water Quality Status of the Reservoir Using the Pollution Index (IP) and STORET Method

Arlina Phelia — 2026-10-30

Increased practical and research activities at the Smart Food Technology Building of the Lampung State Polytechnic may generate laboratory wastewater that could degrade the water quality of the campus reservoir, the receiving water body, if not properly treated. This study aimed to determine the wastewater pollution level in the campus building's drainage channels and assess the water quality status of the reservoir using the Pollution Index (IP) and STORET methods. The parameters analyzed included pH, DO, TDS, TSS, COD, BOD, and Total Coliform. The results indicated that wastewater in the drainage channels was polluted, with COD, BOD, and Total Coliform levels exceeding domestic wastewater quality standards set by the Regulation of the Minister of Environment and Forestry Number 68 of 2016. The reservoir water quality assessment indicated a lightly polluted category under the PI method (average Pij value of 2.47) and a moderately polluted category under the STORET method (score of -30); COD, BOD, and Total Coliform consistently exceeded the Class II quality standards stipulated in Government Regulation Number 22 of 2021 across both methods. Based on these findings, source wastewater management is essential to prevent further deterioration of reservoir water quality.

Carbon Cost Internalization in Mining Operations: A Systematic Literature Review Toward an Activity-Based Framework for Limestone Quarry

F. Purry Widiarko — 2026-10-30

Carbon pricing is becoming increasingly relevant to mining because greenhouse-gas emissions may create additional operating costs through regulatory requirements, carbon-market transactions, or internal economic valuation. This systematic literature review examines how carbon costs have been defined, quantified, and incorporated into mining economics, with particular attention to the development of a research framework for limestone quarrying from land clearing to the crusher hopper. The literature search was conducted from April to June 2026, with the final search completed on 17 June 2026. ScienceDirect was used as the primary literature source and Google Scholar as a supplementary source. Duplicate records were checked using DOI and bibliographic information before title, abstract, and full-text screening against predefined eligibility criteria. Screening was conducted by the first author and subsequently reviewed by the second author. Of 50 peer-reviewed articles assessed, 40 were retained for descriptive classification and thematic synthesis. The main gaps concern limestone-specific applications, integration of land-use-change and operational emissions, and site-based operating costs. The proposed framework distinguishes regulatory carbon-tax obligations, market carbon-unit prices, internal or shadow prices, and hypothetical prices used for stress testing, with Indonesian values treated as scenario inputs rather than assumed quarry-specific liabilities.

Socioeconomic Analysis and System Dynamics Modelling to Support Domestic Wastewater Management: A Case Study of Baruga Sub-district, Kendari City, Southeast Sulawesi

Dwiprayogo Wibowo — 2026-10-30

The alarming condition of domestic wastewater pollution in an area has caused adverse effects on sanitation and threatened human health. This study examines the relationship between socioeconomic conditions and domestic wastewater management. The research approach used a mixed methods approach to assess the environmental conditions in the Baruga sub-district, Kendari City, Southeast Province, in relation to the hazards of domestic waste. A modeling approach was used to review ways to reduce domestic wastewater based on the social conditions of the community using a system thinking and dynamic approach applied in the Powersim Studio application. The results of the study indicate that the domestic wastewater samples collected in the Baruga Village area quantitatively exceeded the quality standards, such as the Total Suspended Solid (TSS), pH, and fat content parameters. The quantitative identification of social factors, such as community awareness, infrastructure availability, and community participation levels, significantly influenced perceptions and government responsibility in wastewater management. The findings also indicate that public understanding of waste management remains low, despite high expectations for improvements in sanitation systems. This study recommends enhancing education, strengthening DWMS infrastructure, and fostering active collaboration between the government and the community to create an effective and sustainable wastewater management system.

Valorization of Sugarcane Molasses into Bioethanol Using an Integrated Distillation-Adsorption System (I-DAS) with 3 Å Zeolite Molecular Sieve

Ni'matul Izza — 2026-10-30

Sugarcane molasses is a sugar-industry by-product rich in fermentable sugars and has potential as a renewable feedstock for bioethanol. This study evaluated bioethanol purification using an integrated distillation-adsorption system (I-DAS) with a 3 Å zeolite molecular sieve at sample-setting temperatures of 85, 90, and 95 °C and one or two sequential purification cycles. Molasses was diluted and fermented for 96 h using Saccharomyces cerevisiae. Distillate was collected in 100 mL fractions and monitored using alcoholmeters, while selected samples were verified by GC-FID. Descriptive results from three replicates showed mean ethanol concentrations of 64.7–65.6% after the first cycle and 81.59–85.00% after the second cycle. A selected product obtained at 95 °C contained 95.95% ethanol by GC-FID.. Process yield decreased from 35.70–41.00% in the first cycle to 19.30–24.00% in the second cycle, indicating a purity-recovery trade-off. Total sugar decreased from 34.11% to 16.12–17.72% after fermentation and 4.17–4.43% in the final product. The I-DAS system therefore shows potential for high-purity bioethanol production from molasses, although product recovery and process control require further optimization.

Identification and Analysis of Microplastic Abundance in Water, Sediment, and Benthic Gastropods in the Upper Reach of the Brugan River, Batu City

Asaku Dinadimu — 2026-10-30

Escalating plastic waste generation in Indonesia threatens aquatic ecosystems as macroplastics degrade into persistent microplastics that contaminate water, sediment, and aquatic biota, ultimately entering the trophic food web. This study aimed to determine the abundance and characteristics of microplastics in water, sediment, and gastropods in the upper reaches of the Brugan River, Batu City, and to examine their relationship with water quality. Quantitative descriptive assessment was conducted across three sampling stations representing distinct land-use regimes. Surface water, benthic sediment, and gastropod samples were collected in-situ. Microplastic were extracted by density separation and organic matter oxidation and analyzed using optical microscopy to determine the number, size, shape, and color of the particles. Water quality parameters were also assessed such as temperature, total suspended solids (TSS), turbidity, flow rate, and flow velocity. Results indicated that microplastics were present in every compartment, with the highest concentrations in sediment at 221 particles/kg dry weight (dw), then gastropods at 187 particles/kg dw, and finally water at 3 particles/L. Microplastic particles with fragments, particles less than one millimeter in diameter, and transparent colors were the most prevalent characteristics. The Bioaccumulation Factor (BAF) was 62.33 L/kg and the Transfer Factor (TF) was equal 0.85, confirming substantial microplastic accumulation within benthic biota.

Preliminary Assessment of Spring Water Sources as Raw Water using the Weighted Arithmetic Water Quality Index in Batu City, Indonesia

Luhur Akbar Devianto — 2026-10-30

Assessing raw-water quality is essential for ensuring a safe drinking-water supply, particularly in municipalities that rely on natural springs. This study evaluated the physicochemical and microbiological quality of six spring-water sources supplying Perumda Air Minum Among Tirto in Batu City, Indonesia. Water samples were collected in December 2024 from Ngesong, Banyuning, Gemulo, Torong Belok, Darmi, and Kasinan. Physicochemical parameters were assessed against Indonesia's Ministry of Health Regulation No. 2 of 2023 and incorporated into the Weighted Arithmetic Water Quality Index (WAWQI) calculations, while Escherichia coli and total coliforms were evaluated separately. Turbidity ranged from 0.02 to 0.05 NTU, total dissolved solids from 118 to 288 mg L⁻¹, and hardness from 62 to 169 mg L⁻¹ as CaCO₃. Banyuning exhibited deviations in pH (6.46) and color (15 TCU), while Gemulo and Darmi recorded the highest nitrate concentrations (11 mg L⁻¹). All springs were classified as having excellent physicochemical water quality under the adopted WAWQI framework, with values ranging from 0.776 to 4.060. Nevertheless, total coliforms were detected in all sources (7–80 CFU/100 mL), whereas E. coli was only identified at Ngesong (20 CFU/100 mL) and Darmi (1 CFU/100 mL), indicates recent fecal contamination which requiring immediate disinfection prior to distribution. It is importance of combining physicochemical WAWQI assessment with independent microbiological monitoring to guide source protection and municipal raw-water management.