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An assessment of aerobic granular sludge (AGS) in a bubbled airlift continuous reactor (BACR) was done to determine the AGS growth kinetics in the continuous reactor and the impact of varied hydraulic retention time (HRT) against the AGS structure. Sodium acetate was used as the sole carbon source with a 100:20 ratio of COD/N synthetic water. The system was operated at five variations of HRT, i.e. 12, 10, 8, 6, and 4 hours, with organic loading rate (OLR) ranging from 1.6 to 4.8 g COD/day in the BACR. Organic removal decreased from 73% to 52%, along with the increment of OLR, while HRT decreased from 12 hours to 4 hours. The kinetics of organic removal in the BACR were examined to get a better understanding of organic removal trends by AGS in a BACR. The models used for biomass growth analysis were the Monod, Contois, Grau second-order, and Stover-Kincannon kinetic models. This study showed that the best suited models for organic removal in BACR were the Grau second-order kinetic model with an a value of 0.1382 and a b value of 1.0776, and the Stover-Kincannon kinetic model with an Rmax of 5.8 g COD/L.day and a KB of 6.24 g COD/L.day.

Artisanal small scale gold mining (ASGM) practices typically use mercury for amalgamation. Near water environments this can degrade water quality and aquatic biota, including algae. Changes in algal communities can reflect water environment disturbance. The aim of this study was to determine if algae can be used as bioindicator of river water quality impacted by ASGM activities. The research was conducted from July to October 2018 at thirty sampling sites along rivers near ASGM areas in several regencies of Indonesia. Composite samples of water and sediment were collected. A plankton net and brushing methods were used to collect planktonic and benthic algae, respectively. The physicochemical parameters of the water and the sediment as well as the dominant algae genera were analyzed statistically with principal component analysis. The results showed that the total mercury concentration in the water ranged from

Kegiatan operasi di bidang migas telah banyak dilakukan, baik itu dikelola oleh pemerintah maupun pihak swasta. PT. X merupakan salah satu perusahaan yang bergerak di bidang eksplorasi, pengolahan serta produksi minyak dan gas bumi di Indonesia yang menggunakan sistem perpipaan dalam proses distribusinya. Penggunaan sistem perpipaan sebagai sarana untuk menyalurkan produk minyak dan gas dianggap lebih efektif dan efisien dari segi kapasitas dan jarak yang ditempuh. Proses penyaluran di area utara PT. X menggunakan fasilitas jalur pipa offshore dan onshore sebagai sarana distribusi produksi minyak mentah. Apabila terjadi kegagalan pada jalur pipa maka dapat mengakibatkan dampak kerugian yang besar seperti kebocoran, tumpahan, dan ledakan. Oleh karena tingginya potensi bahaya dan risiko tersebut maka perlu dilakukan penilaian risiko pada sistem perpipaan yang digunakan, termasuk risiko pada jaringan pipa transmisi crude oil. Pada penelitian ini dilakukan analisis risiko dengan pendekatan loss prevention and risk assessment yang dikembangkan oleh Muhlbauer (2004). Hasil penelitian ini menunjukkan faktor risiko yang paling besar memberikan kontribusi terhadap kemungkinan kegagalan jalur pipa transmisi minyak 18 inci dari A platform sampai S terminal adalah faktor kerusakan oleh pihak ketiga. Segmen pipa yang paling berisiko untuk mengalami kegagalan yang menyebabkan kebocoran tertinggi adalah pada segmen pipa offshore. Sedangkan faktor konsekuensi dengan nilai dampak tertinggi adalah pada segmen riser. Analisis risiko ledakan atau kebakaran dengan metode Dow’s F & EI pada pipa transmisi memiliki nilai sebesar 113,168 dengan kategori intermediate. Hasil tersebut menyatakan bahwa pihak manajemen perusahaan harus memperhatikan dan mengawasi secara lebih seksama pada jaringan pipa transmisi, sehingga dapat melakukan tindakan mitigasi risiko secara cepat apabila terjadi kegagalan pipa. Kata kunci: crude oil , Dow’s F & EI, metode Muhlbauer, pipa transmisi, risk assessment Abstract: Oil and gas operations have been carried out widely, both managed by the government and private parties. PT. X is one of the companies engaged in the exploration, processing and production of oil and gas in Indonesia that used pipeline system in the distribution processes of oil and gas. The use of pipeline systems was considered more effective and efficient in terms of capacity and distance passed by to distribute oil and gas. The operation processes in the northern area of PT. X use offshore and onshore pipeline facilities to distribute crude oil. The event of a failure on the pipeline can cause major loss impacts such as leaks, spills and explosions. The high potential hazards and risks need to be carried out by risk assessment on the pipeline system used, including the risks in the transmission pipeline network of crude oil. In this research, risk analysis with loss prevention and risk assessment approach developed by Muhlbauer (2004), is measured using semi-quantitative pipeline risk on third party index of damage index, corrosion, pipe design, improper operation. The results of this study indicate that the biggest risk factor contributing to the possibility of failure of the 18-inch oil transmission pipeline from A platform to S terminal is the damage factor by third parties. The pipe segment which is most at risk for failure which causes the highest leakage is in the offshore pipeline segment. Whereas the consequence factor with the highest impact value is in the riser segment. Explosion or fire risk analysis with Dow's F & EI method on transmission pipes has a value of 113.168 with an intermediate category. The results stated that the management of the company must pay close attention to and supervise the transmission pipeline network, so that it can carry out risk mitigation actions quickly if a pipe failure occurs. Keywords: crude oil, Dow’s F & EI, Muhlbauer method, risk assessment, transmission pipe

Activated sludge process is one of the wastewater treatment method that is applied for many wastewater types including painting process wastewater of automotive industry. This wastewater is well-known to have high heavy metals concentration which could deteriorate water environment if appropriate performance of the wastewater treatment could not be achieved. In this study, we monitored microbial community diversity in a Painting Biological Treatment (PBT) system. We applied a combination of cultivation and genotypic biological methods based on 16S rRNA gene sequence analysis to identify the diversity of active microbial community. The results showed that active microbes that could grow in this activated sludge system were dominated by Gram-negative bacteria. Based on 16S rRNA gene sequencing analysis, it was revealed that their microbial diversity has close association with Bacterium strain E286, Isosphaera pallida, Lycinibacillus fusiformis, Microbacterium sp., Orchobactrum sp., Pseudomonas guariconensis, Pseudomonas sp. strain MR84, Pseudomonas sp. MC 54, Serpens sp., Stenotrophomonas acidaminiphila, and Xylella fastidiosa with similarity of 86 – 99%. This findings reflects that microbial community in a Painting Biological Treatment (PBT) system using activated sludge process could adapt with xenobiotics in the wastewater and has a wide range of diversity indicating a complex metabolism mechanism in the treatment process.

The Bojongsoang Wastewater Treatment Plant (WWTP) serves to treat domestic wastewater originating from Bandung City, West Java, Indonesia. An abundant amount of nutrients as a result of waste decomposition increases the number of microalgae populations present in the pond of the wastewater treatment plant, thereby causing a population explosion of microalgae, also called algal blooming. In a stabilization pond system, the presence of algal blooming is not desirable because it can decrease wastewater treatment performance. More knowledge about the relationship between the nutrients concentration and algae blooming conditions, such as microalgae diversity, is needed to control and maintain the performance of the wastewater treatment plant. Therefore this study was conducted, in order to reveal the diversity of microalgae in the stabilization pond system and its relationship with the water characteristics of the comprising ponds. The results showed that the water quality in the stabilization pond system of Bojongsoang WWTP supported rapid growth of microalgae, where most rapid microbial growth occurred in the anaerobic pond. The microalgae diversity in the stabilization ponds was very high, with various morphologies, probably affiliated with blue-green algae, green algae, cryptophytes, dinoflagellates and diatoms. This study has successfully produced information on microalgae diversity and abundance profiles in a stabilization pond system.

The optimization of the coagulation of floc remains challenging because it is affected by various factors, including the pH, turbidity, and alkalinity. A jar test is a reliable method to optimize the coagulation conditions; however, it is time-consuming and requires an experienced technician. A convolutional neural network (CNN) can be used to extract the specific image characteristics via learning processes to construct image classification models. In this study, we applied a CNN for predicting the jar test performance. Artificial water adjusted with kaolin and commercial humic acid was initially used. The floc image was recorded using a video camera during the jar test, and models for predicting the turbidity of the supernatants were constructed by inputting the recorded floc images and the level of turbidity as the training dataset. The learning curve denoted that all the models exhibited 100% accuracy during the learning process, clearly indicating that the CNN worked appropriately with respect to the extraction of the characteristics of the floc images and the determination of their settleability. Subsequently, the overfitting level was investigated by inputting the test data into the models. The maximum prediction accuracy of all the models exceeded 96%. The initial 100 s of the model’s learning of the floc images achieved a maximum accuracy of 99.6%, i.e., the images captured during rapid mixing were sufficient to ensure the reliability of the model. The applicability of the model to natural water samples was also investigated using samples obtained during different months. Even though the accuracy for natural water was lower than that for artificial water, 90% accuracy was achieved even when fluctuating natural water was used, demonstrating the applicability of a CNN to extract the characteristics of the floc governing its settleability and to immediately as well as automatically predict the state of coagulation.

Pollution of water resources is a major risk to human health and water quality throughout the world. Here, we studied the effect of river pollution on the microbial community composition in the Citarum River Basin, West Java, Indonesia. Sediment was collected at six sampling points along a gradient of pollution, from the pristine source of the river to the heavily polluted downstream site in the densely populated urban area of Bandung. After DNA extraction, microbial diversity and potential for nitrogen cycling were analyzed based on 16S rRNA gene amplicon sequencing and metagenomics. Comparing the pristine sediment to the polluted site showed a lower microbial diversity and higher dominance of anaerobic processes than at the polluted site. The most dominant phylum within the Bacteria were theProteobacteria, which shifted fromBeta- andDeltaproteobacteriain the pristine site toAlpha- andGammaproteobacteriain the polluted sediment. With pollutionActinobacteria, Bacteroidetes,andFirmicutesincreased in relative abundance. Relative high abundance ofSoil Crenarchaeotic groupwas found in all sample sites, whilst the methanogenic archaea became more abundant with increased pollution and anaerobicity. The study of the nitrogen cycling potential revealed that ammonium oxidation and denitrification appeared to be abundant processes in the pristine site, whereas ammonification seemed to be more important in the polluted site. Increased water treatment would restore water quality and microbial diversity in Citarum river sediments.

Acidic deposition (acid rain) has been known to cause negative impact to environment. Measurement of rain chemical composition was done in March to August 2016 to investigate temporal variation of atmospheric deposition in Bandung City. Rainwater samples are collected at four sampling sites. The chemical properties of the rain determined were pH and ionic concentrations of SO42-, NO3-, Cl-, Ca2+, Mg2+, Na+, K+ and NH4+. The rainwater was typically acidic with the range of mean pH between 5.29 – 5.56 and mean electric conductivity value range between 16.37 – 19.96 μS/cm. Temporal variation showed higher SO42+, NO3+ and NH4+ concentration in August when rainfalls were the lowest (214.88 mm). Similar temporal variation for the mean pH (5.98) and electric conductivity (25.36 μS/cm) in August. Ca2+ highest concentration was observed in June. Generally, the the major component of precipitation chemistry were SO42- and NO3-, Ca+ and NH4+, for anion and cations, respectively. The largest proportions of the total anions in all sampling sites was SO42- ranged from 32% (Lembang) to 37% (Buah Batu) followed by NO3- (13 – 15%) and and Cl- (4 – 7%). For cations, NH4+ dominated with proportion ranged between 21 – 27% and subsequently Ca2+ (13 – 19%) and followed by Na+, Mg+, K+ and H+. The Neutralizing Factor (NF) results reveal that Ca2+ and NH4+ are the dominant neutralization substances in the rainwater. However it should be noted that reduced nitrogen (NH4+) act as mobile nitrogen that further will acidify the environment, particularly to soil ecosystem downstreams.

In general, small-scale gold mining activities that are spread throughout Indonesia practicing amalgamation technique. The amalgamation process in the mining activities can result in environmental degradation due to tailing waste containing mercury that are discharged into the environment and will distributed and bioaccumulated through food chain. Mercury exposure to human can give a chronic effect. Measuring mercury concentration in biomarkers such as nail and hair is a method to indicate the mercury poisoning level. Therefore, the purpose of this study was to analyze mercury concentrations in nail and hair as chronic exposure biomarkers. Besides, we also conducted Human Biomonitoring (HBM) analysis to assess mercury intoxication in the communities. Moreover, we analyzed mercury concentrations in water, rice, fish, and food crops samples to understand their association with mercury concentrations in nail and hair through a Provisional Tolerable Weekly Intake (PTWI) analysis. This research was conducted in 4 districts in Indonesia which has a significant number of small-scale gold mining activities. The results showed that the maximum concentration of T-Hg in the nail and hair of the workers was 58.48 µg/g and 55.97 µg/g, respectively. Based on HBM analysis, in several districts, more than 60% of the workers has been intoxicated by mercury. Meanwhile, Average Daily Intake (ADI) and PTWI were significantly correlated with concentration mercury in the nail and hair. Mercury concentrations in worker’s hair was significantly correlated with working experience. We identified that the age and residence duration were the major predictor of concentration mercury in nail and hair, respectively.

Kegiatan tambang emas tradisional berpotensi menimbulkan pencemaran lingkungan akibat penggunaan merkuri, seperti yang dilakukan di Desa Lebaksitu, Kecamatan Lebakgedong, Kabupaten Lebak, Banten. Merkuri digunakan sebagai pengikat unsur emas dalam proses amalgamasi. Pencemar merkuri yang masuk ke lingkungan dapat menyebar ke daerah sekitarnya melalui air, penyerapan oleh tumbuhan dan bioakumulasi pada rantai makanan. Dari hasil analisis Hg di dalam tanah diperoleh kisaran nilai 15.200 – 226.894 ppb untuk daerah Lebaksampai, 4.275 - 93.925 ppb untuk daerah Lebaktenjo, dan 15.881 – 102.888 ppb untuk daerah Lebakpari. Tanaman padi yang tumbuh pun memiliki kandungan Hg yang tinggi. Sebagian besar sampel beras yang diperiksa mengandung lebih dari 0,05 ppm merkuri sehingga berisiko terhadap kesehatan penduduk. Penyebaran kuesioner terhadap 30 rumah dengan 126 orang responden didapat data jumlah konsumsi, frekuensi paparan, dan berat badan untuk perhitungan ADD dan HI. Nilai ADD yang didapat berkisar antara 0,825 – 2,177 ppb/hari untuk anak perempuan berusia dibawah 13 tahun, sedangkan untuk anak laki-laki berkisar antara 0,840 – 2,177 ppb/hari. Untuk orang dewasa, nilai ADD wanita berkisar antara 0,356 – 0,800 ppb/hari dan nilai ADD pria berkisar antara 0,327 – 0,816 ppb/hari. Sedangkan untuk manula di atas 60 tahun, nilai ADD wanita sebesar 0,712 dan pria sebesar 0,506 – 0,632. Dengan menggunakan nilai reference dose 0,3 ppb/hari, didapat nilai HI. Nilai HI yang didapat untuk seluruh responden lebih dari 1 atau konsumsi tersebut dapat berpotensi menimbulkan efek non-karsinogenik.

Water quality indices (WQI) using STORET method has been used to assess rainwater quality in the Bandung urban regions, based on monitoring data at three locations (Coblong, Sumur Bandung, and Buah Batu). Rainwater samples were analyzed by detecting pH, SO4 2-, NO3 −, Cl−, and heavy metals (As, Cd, Cr, Pb, and Zn) compared with Indonesian Government Regulation No. 82 Year 2001. Rainwater quality showed polluted based on the parameters of the water quality indices analysis using the Class I and Class II criteria. Rainwater quality in Bandung urban region were lightly polluted (Coblong) and moderately polluted (Sumur Bandung and Buah Batu). Rainwater can potentially become a water sources alternative for domestic use and urban farming in Bandung urban region, but it requires further treatment for better quality.

Saat ini DAS Citarum Hulu tengah mengalami penurunan kualitas air sungai. Salah satu penyebab terjadinya permasalahan ini adalah adanya pencemaran pada anak sungai yang masuk ke badan air Citarum Hulu. Sungai Cikapundung merupakan salah satu anak sungai yang turut berkontribusi dalam penurunan kualitas air Sungai Citarum Hulu. Usaha pencegahan pencemaran yang efektif dan efisien hanya dapat dilakukan apabila sumber pencemar telah diketahui. Salah satu upaya yang dapat dilakukan dalam pelacakan sumber pencemar adalah Microbiological Source Tracking (MST). Terdapat dua metode utama dalam MST yaitu konvensional dan modern. Antibiotic Resistance Analysis (ARA) merupakan salah satu cara modern dalam mendeteksi bakteri yang bertujuan membedakan diversitas resistensi bakteri terhadap antibiotik sehingga dapat terlihat perbedaan pola resistensi dan dapat diidentifikasi sumber bakterinya. Pada Sungai Cikapundung, pelacakan E. coli dilakukan dengan menguji resistensi dari tiap isolat yang diambil dari 3 titik sampling di sepanjang badan air terhadap 10 jenis antibiotik. Pada titik 1 yang terletak di hulu Cikapundung, belum ditemukan adanya pencemaran fekal. Sedangkan, sebaran E. coli pada titik 2 dan 3 berasal dari sumber manusia. Dengan diketahuinya sumber pencemar spesifik, maka diharapkan dapatdilakukan penanganan lebih lanjut yang tepat sasaran.

A paradigm shift in waste processing is done to obtain additional benefits from treated wastewater. By using the appropriate processing, wastewater can be turned into a resource. The use of aerobic granular biomass (AGB) can be used for such purposes, particularly for the processing of nutrients in wastewater. During this time, the use of AGB for processing nutrients more reactors based on a Sequencing Batch Reactor (SBR). Studies on the use of SBR Reactor for AGB demonstrate satisfactory performance in both formation and use. SBR reactor with AGB also has been applied on a full scale. However, the use use of SBR reactor still posses some problems, such as the need for additional buffer tank and the change of operation mode from conventional activated sludge to SBR. This gives room for further reactor research with the use of a different type, one of which is a continuous reactor. The purpose of this study is to compare AGB formation using continuous reactor and SBR with same operation parameter. Operation parameter are Organic Loading Rate (OLR) set to 2,5 Kg COD/m3.day with acetate as substrate, aeration rate 3 L/min, and microorganism from Hospital WWTP as microbial source. SBR use two column reactor with volumes 2 m3, and continuous reactor uses continuous airlift reactor, with two compartments and working volume of 5 L. Results from preliminary research shows that although the optimum results are not yet obtained, AGB can be formed on the continuous reactor. When compared with AGB generated by SBR, then the characteristics of granular diameter showed similarities, while the sedimentation rate and Sludge Volume Index (SVI) characteristics showed lower yields.A paradigm shift in waste processing is done to obtain additional benefits from treated wastewater. By using the appropriate processing, wastewater can be turned into a resource. The use of aerobic granular biomass (AGB) can be used for such purposes, particularly for the processing of nutrients in wastewater. During this time, the use of AGB for processing nutrients more reactors based on a Sequencing Batch Reactor (SBR). Studies on the use of SBR Reactor for AGB demonstrate satisfactory performance in both formation and use. SBR reactor with AGB also has been applied on a full scale. However, the use use of SBR reactor still posses some problems, such as the need for additional buffer tank and the change of operation mode from conventional activated sludge to SBR. This gives room for further reactor research with the use of a different type, one of which is a continuous reactor. The purpose of this study is to compare AGB formation using continuous reactor and SBR with same operation parameter. Operatio...

Salah satu unsur dalam pengolahan air limbah menggunakan reaktor constructed wetland adalah degradasi polutan oleh mikroorganisme yang terdapat pada tanah. Mikroorganisme membutuhkan nutrient berupa zat organik untuk proses metabolisme, sehingga dapat memanfaatkan zat-zat organik yang terdapat dalam air limbah. Studi ini dilakukan untuk mengidentifikasi dan mengetahui karakteristik bakteri yang ditemukan pada reactor wetland tersebut dan menganalisis sifat bakteri berupa kurva tumbuh. Bakteri diisolasi dari tanah pada reaktor, kemudian diidentifikasi menggunakan API 20 NE dan dan diukur kurva tumbuhnya menggunakan metode tidak langsung. yaitu dengan spektrofotometri hingga tercapai fase stasiuner, kemudian diinokulasi ke dalam air limbah domestik untuk mengukur kemampuan bakteri untuk hidup dalam air limbah. Dari kesembilan bakteri yang diisolasi, seluruhnya bersifat Gram negatif dan berbentuk batang atau batang pendek. Identifikasi bakteri menunjukkan bahwa bakteri berasal dari genus Aeromonas, Pseudomonas, Empedobacter, Moraxella, Vibrio, Ralstonia, dan Brevundimonas. Kurva tumbuh untuk masing-masing bakteri menunjukkan bahwa pada bakteri Aeromonas hydrophilia tidak didapat fase lag atau fase lag kurang dari satu jam. Sedangkan dalam perhitungan laju pertumbuhan eksponensial (K), mean doubling time (g), dan konstanta laju pertumbuhan spesifik (µ), didapat bahwa bakteri ini juga memiliki nilai g yang paling kecil. Bakteri yang diinokulasi ke dalam air limbah menunjukkan bahwa seluruh bakteri dapat menyisihkan COD, dengan penurunan COD terbesar oleh Moraxella dan terkecil oleh Pseudomonas luteola. Abstract : One element in treating wastewater using a constructed wetland reactor is the degradation of pollutants by microorganisms found in soil. Microorganisms require various organic substrates to fuel metabolic processes, which can utilize organic substances found in wastewater. This study is conducted to identify and characterize the bacteria found in the wetland reactor and to analyze the bacteria characteristics by mapping a growth chart for each of the bacteria. The bacteria is isolated from the reactor and identified using API 20 NE, and the growth curve is measured using spectrophotometry up to a stationary phase. The bacteria is then inoculated into domestic wastewater to measure the ability of the bacteria to live in wastewater. All nine bacteria that were isolated were Gram negative and were rods or short rods. Identification of the bacteria showed that the bacteria were from the genus Aeromonas, Pseudomonas, Empedobacter, Moraxella, Vibrio, Ralstonia, and Brevundimonas. The growth curve showed that the bacteria Aeromonas hydrophilia did not experience a lag phase or the lag phase was very short. This bacteria also had the shortest mean doubling time (g). Wastewater samples which were inoculated with bacteria showed a decrease of COD in all samples, with the largest decrease by the bacteria Moraxella and the lowest by Pseudomonas luteola.

Biodegradasi dengan metode lumpur aktif dilakukan dengan memanfaatkan bakteri yang digunakan selama proses pengolahan yang kemudian diresirkulasi kembali ke proses setelah mengalami pengendapan. Pengolahan ini dapat juga diterapkan pada pengolahan limbah cat. Tujuan dari penelitian ini adalah untuk mengidentifikasi bakteri pendegradasi limbah cat dari lumpur hasil pengolahan serta membandingkannya dengan keberagaman bakteri yang ada pada commercial seed . Bakteri yang dihasilkan dari identifikasi pada lumpur terdiri dari lima jenis, yaitu Bacillus subtilis, Bacillus licheneformis, Bacillus cereus, Bacillus megaterium, dan Pseudomonas flourescens. Keberadaan bakteri-bakteri tersebut menunjukkan proses pengolahan menggunakan bakteri konsorsium yang setiap bakterinya memiliki pola perumbuhan yang berbeda. Hal itu ditunjukkan oleh perbedaan waktu generasi(g) dan konstanta laju pertumbuhan (k). Nilai waktu generasi dan konstanta laju pertumbuhan adalah 44,67 menit dan 0,93 jam -1 untuk Pseudomonas flourescens; 45,04 menit dan 0,92 jam -1 untuk Bacillus subtilis; 35 menit dan 1,17 jam -1 untuk Bacillus licheniformis; 18 menit dan 2,27 jam -1 untuk Bacillus cereus, 19 menit dan 2,18 jam -1 untuk Bacillus megaterium, serta 53 menit dan 0,79 jam -1 untuk kultur campuran. Bakteri commercial seed yang digunakan pada saat pengolahan dan kembali terdapat di lumpur hasil pengolahan menandakan bahwa bakteri tersebut mampu menggunakan limbah sebagai sumber karbon dan berperan dalam pengolahan limbah. Abstract : Biodegradation with activated sludge method is done by using bacteria that are used during treatment process, which was then returned to the treatment process after had been settled. This process can be applied to liquid waste paint treatment. The objectives of this research are to identify the paint waste degradation bacteria of sludge and to compare them with the bacterial types in the commercial seed. The result of bacteria identification from sludge obtained five species. They are Bacillus subtilis, Bacillus licheneformis, Bacillus cereus, Bacillus megaterium, and Pseudomonas flourescens. The presence of five kinds bacteria indicates that the biological process used a consortium bacteria, that has different growth pattern. It was shown by the difference of generation time(g) and growth rate constant of (k) both pure cultures and mixed culture. Value of generation time (g) and growth rate constant (k) for each bacteria were 44.67 minutes and 0.93 hour -1 for Pseudomonas flourescens; 45.04 minutes and 0.92 hour -1 for Bacillus subtilis; 35 minutes and 1.17 hour -1 for Bacillus licheniformis; 18 minutes and 2.27 hour -1 for Bacillus cereus, 19 minutes and 2.18 hour -1 for Bacillus megaterium, and 53 minutes and 0.79 hour -1 for mixed culture. Commercial seed bacteria used during the treatment process and then present in the produced sludge indicates that the bacteria are able to use waste as a source of carbon, and indeed a role in waste treatment process. Key words : paint waste sludge, identification, generation time, growth rate constant

Wastewater and solid waste from both domestic and industry have been known to give burden on river water quality. Most of river water quality problem in Indonesia has start in the upper part of river due to anthropogenic activities, due to inappropriate land use management including the poor wastewater infrastructure. Base on Upper Citarum River Water pollution problem, it is interesting to study the other main river in Java Island. Bengawan Solo River and Brantas River were chosen as the sample in this study. Parameters assessed in this study are as follows: TSS, TDS, pH, DO, and hexavalent chromium. The status of river water quality are assess using STORET method. Based on (five) parameters, STORET value showed that in Brantas River, Pagerluyung monitoring point had the worst quality relatively compared to other monitoring point in Brantas River with exceeding copper, lead and tin compared to the stream standard in East Java Provincial Regulation No. 2 in 2008. Brantas River was categorized as lightly polluted river based on monitoring period 2011-2015 in 5 monitoring points, namely Pendem, Sengguruh, Kademangan, Meritjan and Kertosono.

We investigated the major phylogenetic groups and population size of glucose-, propionate-, and acetate-degrading bacteria in the glucose-degrading anaerobic digester sludge by stable-isotope probing analysis of 16S rRNA (RNA-SIP) with [(13)C(6)]glucose followed by time course analysis of microautoradiography combined with fluorescent in situ hybridization (MAR-FISH) with [U-(14)C]glucose. The results indicated that glucose was predominately degraded to CH(4) and CO(2) by glucose-degrading Propionibacterium and Olsenella that are belonging to the phylum Actinobacteria, propionate-degrading Smithella and Syntrophobacter, and acetate-degrading Methanosaeta and Synergistes group 4 in this anaerobic sludge. The population size of propionate degraders was the smallest among three trophic groups and the specific degradation rate of propionate was also low. The specific degradation rate of acetate was low even though their population size was comparable to the glucose degraders. These results could explain why the degradation of propionate and acetate was the rate-limiting step in methanogenic glucose degradation.

Major acetate-utilizing bacterial and archaeal populations in methanogenic anaerobic digester sludge were identified and quantified by radioisotope- and stable-isotope-based functional analyses, microautoradiography-fluorescence in situ hybridization (MAR-FISH) and stable-isotope probing of 16S rRNA (RNA-SIP) that can directly link 16S rRNA phylogeny with in situ metabolic function. First, MAR-FISH with (14)C-acetate indicated the significant utilization of acetate by only two major groups, unidentified bacterial cells and Methanosaeta-like filamentous archaeal cells, in the digester sludge. To identify the acetate-utilizing unidentified bacteria, RNA-SIP was conducted with (13)C(6)-glucose and (13)C(3)-propionate as sole carbon source, which were followed by phylogenetic analysis of 16S rRNA. We found that bacteria belonging to Synergistes group 4 were commonly detected in both 16S rRNA clone libraries derived from the sludge incubated with (13)C-glucose and (13)C-propionate. To confirm that this bacterial group can utilize acetate, specific FISH probe targeting for Synergistes group 4 was newly designed and applied to the sludge incubated with (14)C-acetate for MAR-FISH. The MAR-FISH result showed that bacteria belonging to Synergistes group 4 significantly took up acetate and their active population size was comparable to that of Methanosaeta in this sludge. In addition, as bacteria belonging to Synergistes group 4 had high K(m) for acetate and maximum utilization rate, they are more competitive for acetate over Methanosaeta at high acetate concentrations (2.5-10 mM). To our knowledge, it is the first time to report the acetate-utilizing activity of uncultured bacteria belonging to Synergistes group 4 and its competitive significance to acetoclastic methanogen, Methanosaeta.

The phylogenetic and functional diversity of syntrophic propionate-oxidizing bacteria (POB) present in an anaerobic digester was investigated by microautoradiography combined with fluorescent in situ hybridization (MAR-FISH) that can directly link 16S rRNA phylogeny with in situ metabolic function. The syntrophic POB community in the anaerobic digester sludge consisted of at least four phylogenetic groups: Syntrophobacter, uncultured short rod Smithella (Smithella sp. SR), uncultured long rod Smithella (Smithella sp. LR), and an unidentified group. The activities of these POB groups were dependent on the propionate concentrations. The uncultured Smithella sp. SR accounted for 52-62% of the total active POB under all the propionate concentrations tested (0.5-15 mM). In contrast, uncultured Smithella sp. LR was active only at lower propionate concentrations and became a dominant active POB at 0.5 mM of propionate. Syntrophobacter accounted for 16-31% of the total active POB above 2.5 mM propionate, whereas the active Syntrophobacter population became low (ca. 6%) at 0.5 mM of propionate. The anaerobic digester was operated in a fill and draw mode, resulting in periodical changes in propionate concentration ranging from 0 to 10 mM. These phylogenetically and functionally diverse, to some extent functionally redundant, active POB communities were dynamically responding to the periodical changes in propionate concentration.

Functional Bacteria and Archaea community structures of a full-scale anaerobic sludge digester were investigated by using a full-cycle 16S rRNA approach followed by microautoradiography (MAR)-fluorescent in situ hybridization (FISH) technique and micromanipulation. FISH analysis with a comprehensive set of 16S and 23S rRNA-targeted oligonucleotide probes based on 16S rRNA clone libraries revealed that the Gram-positive bacteria represented by probe HGC69A-hybridized Actinobacteria (8.5+/-1.4% of total 4', 6-diamidino-2-phenylindole (DAPI)-stained cells) and probe LGC354-hybridized Firmicutes (3.8+/-0.8%) were the major phylogenetic bacterial phyla, followed by Bacteroidetes (4.0+/-1.2%) and Chloroflexi (3.7+/-0.8%). The probe MX825-hybridized Methanosaeta (7.6+/-0.8%) was the most abundant archaeal group, followed by Methanomicrobiales (2.8+/-0.6%) and Methanobacteriaceae (2.7+/-0.4%). The functional community structures (diversity and relative abundance) of major trophic groups were quantitatively analyzed by MAR-FISH. The results revealed that glucose-degrading microbial community had higher abundance (ca. 10.6+/-4.9% of total DAPI-stained cells) and diversity (at least seven phylogenetic groups) as compared with fatty acid-utilizing microbial communities, which were more specialized to a few phylogenetic groups. Despite the dominance of Betaproteobacteria, members of Chloroflexi, Smithella, Syntrophomonas and Methanosaeta groups dominated the [(14)C]glucose-, [(14)C]propionate-, [(14)C]butyrate- and [(14)C]acetate-utilizing microorganism community, and accounted for 27.7+/-4.3%, 29.6+/-7.0%, 34.5+/-7.6% and 18.2+/-9.5%, respectively. In spite of low abundance (ca. 1%), the hitherto unknown metabolic functions of Spirochaeta and candidate phylum of TM7 as well as Synergistes were found to be glucose and acetate utilization, respectively.