<![CDATA[Abstrak. Sungai Lok Ulo di Kabupaten Kebumen, Jawa Tengah, merupakan wilayah dengan aktivitas penambangan emas aluvial yang cukup intensif. Aktivitas ini berpotensi menurunkan kualitas air sungai, yang merupakan sumber air penting bagi masyarakat sekitar. Penelitian ini bertujuan mengevaluasi dampak penambangan emas aluvial terhadap kualitas air Sungai Lok Ulo menggunakan pendekatan analisis laboratorium yang sistematis. Parameter yang dianalisis meliputi Total Dissolved Solids (TDS), Total Suspended Solids (TSS), pH, serta kandungan logam berat seperti besi (Fe), mangan (Mn), dan seng (Zn). Uji statistik ANOVA digunakan untuk menilai hubungan antara aktivitas penambangan dan perubahan kualitas air. Hasil menunjukkan peningkatan kadar TSS hingga 78% pasca penambangan, sementara pH air turun menjadi 6,2, mengindikasikan kecenderungan keasaman. Konsentrasi logam berat, khususnya Fe (0,93 mg/L) dan Mn (0,45 mg/L), melebihi ambang batas kualitas air sesuai standar nasional. Analisis ANOVA mengonfirmasi adanya hubungan signifikan antara aktivitas penambangan dan penurunan kualitas air. Temuan ini menegaskan bahwa penambangan emas aluvial di kawasan tersebut berdampak negatif terhadap lingkungan perairan dan menyoroti pentingnya penerapan strategi pengelolaan yang lebih berkelanjutan untuk meminimalkan pencemaran. Abstract. The Lok Ulo River, located in Kebumen Regency, Central Java, is a region experiencing intensive alluvial gold mining activities. These operations have the potential to degrade water quality, which is crucial for the surrounding communities. This study analyzes the environmental impact of such mining using a comprehensive scientific method. Water quality was assessed through several parameters, including Total Dissolved Solids (TDS), Total Suspended Solids (TSS), pH, and heavy metal concentrations such as iron (Fe), manganese (Mn), and zinc (Zn). Samples were collected from upstream, midstream, and downstream locations near mining sites. Statistical analysis using ANOVA was applied to determine the relationship between mining intensity and changes in water quality. The results show that mining significantly increased TSS levels by up to 78% compared to pre-mining conditions. The pH dropped from neutral to 6.2, indicating increased acidity. Heavy metals, particularly Fe (0.93 mg/L) and Mn (0.45 mg/L), exceeded Indonesian water quality standards. ANOVA results confirmed a statistically significant correlation between mining activity and water quality degradation. These findings highlight the environmental risks of alluvial gold mining in the Lok Ulo River and emphasize the need for stronger environmental management and mitigation strategies to preserve water quality and protect local ecosystems.]]>
