Report for 2002GU4B: Impact of Ordot Dump on Water Quality of Lonfit River Basin in Central Guam (original) (raw)
Related papers
Impact of Ordot Dump on Water Quality of Lonfit River Basin in Central Guam
2015
Guam’s only municipal solid waste disposal site is centrally located in the village of Ordot and has been in use for over fifty years. Lacking in the conventional technology built in to modern day sanitary landfills, the site is essentially an open dump covering ~20 acres of the upper Lonfit River valley. The dump was operated by the US Navy at the end of WWII and transferred to the Government of Guam shortly thereafter. Although slated for closure more than 20 years ago, it still receives around 200 tons of solid waste per day from the civilian community. Early records of the types of materials disposed of at the Ordot Dump are nonexistent but are suspected to include the same array of toxic chemicals found at other military dumpsites on island. Today, there is some control over the bulk disposal of industrial chemicals, waste oil, and metallic waste at Ordot Dump. However, household waste is rarely screened and is known to contain a variety of hazardous substances, both biological...
Micronesica, 2008
Leachate samples taken from the perimeter of the Ordot Landfill, in central Guam, were screened for priority pollutants listed under Section 307(a) of the Clean Water Act. Identified contaminants of concern were the fecal indicator bacteria, Enterococci and E. coli, inorganic nitrogen (N) and phosphorus (P), and several heavy metals. These contaminants were monitored in surface and subsurface waters down gradient of the landfill at monthly intervals for one year. Fecal indicator bacteria MPN counts in receiving surface waters dropped sharply within a few hundred meters downstream of leachate stream impaction points. However, values often exceeded the U.S. EPA recreational water quality standards all the way to the coast. Inorganic N was dominated by ammonium in the leachate stream and nitrate in the river. Occasional exceedences of the U.S. EPA surface water quality standard for nitrate (as NOx) were observed at all downstream sites. Inorganic (reactive) P was mostly undetectable in surface waters despite relatively high levels in the leachate stream. Likewise, heavy metal contaminants that were enriched in the leachate stream were mostly close to the limits of analytical detection in the river. Soil pore waters collected at various depths (0.61-1.83 m) ~100 m down gradient of the landfill were comparatively free of fecal indicator bacteria. Inorganic nitrogen levels, though enriched, were appreciably lower than those in the leachate stream, suggesting either denitrification, high assimilation by soil microbes, and/or high sorption by clays. Average P levels were also low suggesting removal by oxidic iron in surface layers. Neither inorganic N nor P concentrations varied significantly with soil depth. In contrast, mean pore water concentrations of aluminum, cadmium, iron and zinc were generally more concentrated at the shallowest soil level. Inorganic N enrichment, and its effect on plant and algae growth in the lower reaches of the Lonfit River, was considered to be the most significant ecological impact of the landfill on the watershed. The transmission of human pathogens from the landfill into the river, in leachate streams and surface runoff, and the incorporation of potentially toxic metals into food chains ultimately leading to man, are likely the most important issues from a human health perspective. Micronesica 40(1/2), 2008 150 Figure 1. Map of study area showing location of leachate (*), surface water (R1-R5) and pore water (L1-L5) collection sites down gradient of Ordot Landfill, Guam.
Leached from Ordot Landfill in Surface and Subsurface Flows
2005
for ignoring the stench, the flies, the wild pigs and the boony dogs to bravely go where no man has gone before! You battled sword grass, tangled thickets and plagues of pesky mosquitoes to get us to our sampling sites in that hot and humid undergrowth. Your spirited good humor and unflagging efforts were much appreciated. Thank you both. The invaluable assistance of Lucrina Concepcion (FENA Laboratory, Guam), who painstakingly performed the ICP elemental analysis of all surface water and pore water samples, is gratefully acknowledged. We are indebted to Carmen Sian-Denton for organizing the shipment of leachate samples to a reputable off-island laboratory, and for proofreading the draft copy of this report. Our esteemed thanks go to Norma Jean Blas for organizing the photocopying, printing, and binding of the final document. Finally, we would like to thank Dr. Leroy Heitz, Director of WERI at the University of Guam, for his continued support and encouragement during the course of this study. v
Aqueous Contaminants Leached from Ordot Landfill in Surface and Subsurface Flows
2005
Pago Bay was suspected of being the final resting place for heavy metal contaminants discharged into the Lonfit River from the Ordot Dump. To test this hypothesis, surface sediments (top 1-3 cm) were collected from 44 sites within the bay in January 2005. Thirty-two of these sites were located intertidally at ~100-m intervals along the beach. The remaining sites were positioned at ~100-200m intervals along five transect lines running perpendicular to the shore. Later in the year, (June-September 2005), dominant biotic representatives (algae, seagrass, seacucumbers and bivalves) were taken for analysis from 48 sites within the bay in order to identify any metal uptake abnormalities that might be occurring in the resident fisheries resources. Biota collection sites were largely confined to the inner moat and outer reef flat. The organisms selected for study were chosen because of their known or suspected bioindicator potential and their ability to reflect biologically available metal fractions in specific segments of the environment. Algae, for example, only respond to the soluble metal fraction in the water column, whereas seagrasses derive their metal load mainly from sediment pore waters via their root systems. Seacumbers are sediment ingesters, while bivalves obtain their trace metal load from both suspended particulates and the soluble fraction in the surrounding water. Data from such a suite of organisms thus provides the investigator with a means of differentiating between sediment-bound and soluble metal fractions and rating the relative importance of each.
2017
One of the main environmental concerns regarding the operation of landfills is the leaching and transport of contaminants from the landfill into nearby surface water and into groundwater. The Montalban Solid Waste Disposal Facility (MSWDF) located in Rodriguez, Rizal, (referred to in this work as the "landfill"), has been perceived to pose serious and immediate problems. A concern arises from the selection of the site, being situated on a mountain ridge, around 250 m elevation, with a heavily fractured volcanic geology. Surface water affected by the landfill comprises one of the headwaters of the Marikina River system which drains the Marikina river watershed. In view of the hydrologic setting, the operators and regulators are faced with the challenge of implementing adequate precautionary measures to protect the water supply from deterioration. To determine the degree of mitigation required to ensure that the water sources are adequately protected, and to ensure that resources are spent in the most cost-effective manner, a risk assessment of the MSWDF is necessary. The MSWDF is considered to be a contaminated site which may pose a risk if toxic substances that may be present in the leachate reach a receptor. Risk assessments of contaminated sites are usually based on source-pathway-receptor concept where the pathway is the mechanism by which a contaminant gets from the source to the receptor. A given source is considered a risk if a complete pathway-linkage exists between the source and the receptor. In this case, a complete pathway consists of a leachate release from the landfill, a transport media (surface water, groundwater, and soil), and an exposure route at the receptor contact point. In this case, the contaminant can reach a human being through ingestion or dermal contact. The goal of this thesis is to provide suitable scientific basis for risk assessment of the landfill. It focuses primarily on the "source-pathway" part of the risk assessment. A number of factors and processes influence the distribution, fate and transport of the contaminants in the environment. Among these are the hydrologic setting, which determines the prevalent pathways of contaminant migration, the composition of the soils and geologic materials in the unsaturated zone, which influences the mobility of contaminants, and the potential for biodegradation of the waste materials in the prevailing environment. The approach in this thesis is to conduct site investigations to characterize the source and to determine the spatial and temporal contamination of surface water and groundwater from landfill leachate, and to perform sorption and degradation experiments to assess the attenuation potential of the system. The results of these studies will provide information needed for future modeling efforts to predict the resulting contaminant impact on the surface water and groundwater downstream of the source. The characterization of the contaminant source, i.e., the leachate, focuses on the isotopic composition of hydrogen and oxygen, major ions, and selected metals. These components are similarly investigated in the surface water and groundwater. These components are meant to merely indicate the potential occurrence of groundwater contamination from the landfill, which may be hazardous due to their toxicity and/or persistency if they move through the aquifer towards the water supply. The detection of these indicators of leachate contamination in the freshwater should provide impetus for further investigations on specific hazardous contaminants that may be present in the leachate and may have reached the water
Ecotoxicological Assessment of Leachate from Municipal Solid Waste Dumpsites
Journal of Experimental and Clinical Toxicology, 2019
The ecotoxicological effects of leachates from dumpsite have become a major problem. Leachates arising from waste dumpsites are transported by surface runoff or infiltration through the soil and become bioavailable in the ecosystem. The ecotoxicological assessment of leachates from 6 dumpsite in Yenagoa Metropolis were investigated against adult and fingerlings of Clarias gariepinus (African catfish). Ecotoxicological activities (LC50 values) were reported for the following stations; Akenpai (124.57 ppm), and Etegwe stations (95.38 ppm), as well as Opolo (157.95 ppm), and Kpansia Markets (123.82 ppm). In addition, leachates of the two stations from the central dumpsite (CDS), were the most active (CDS 1; 60.97 ppm, and CDS 2; 76.65 ppm). Notwithstanding, the order of toxicological activities of the leachates were reported as; CDS 1>CDS2>Etegwe>Akenpai>Kpansia market>Opolo Market. These results confirm the toxicity of leachates from the dumpsites. In addition, we recom...
Comparative Analysis of the Level of Contaminants in Select Waterways Sample from Dumpsites
Background: Environmental and water pollution are major global problems that require ongoing evaluations. Water pollution is a form of environmental degradation when pollutants are directly or indirectly discharged into water bodies without adequate treatment to remove harmful compounds. However, improper disposal of waste is majorly responsible for the degree of water contamination in recent times. Objectives: This study was to compare the levels of contaminants of Ekulu water way using sampled water from dump sites in Emene Suburb of Enugu State to the WHO standards. Other goals were to determine the physicochemical status of the River, as well as the assessment of the predominant pollutants. Water samples were collected from waste water close to three dump sites which include; waste water close to a refuse dump site (sample A), water close to a piggery (sample B), and waste water close to the dumpsite from Chigozie's hospital (sample C). Results: Compares were made with the WHO standards which include colour-unobjectionable, hydrogen ion concentration-6.5-9.0. conductivity-1000µs/cm, alkalinity-3.0-50.0mg/l, dissolved solids-500mg/l, chemical oxygen demand-250mg/l, calcium-75ppm, sodium-50ppm, magnesium-≤30ppm, potassium-12ppm, cooper-1.30ppm, manganese-0.1-0.5 ppm, lead-0.001ppm, zinc – 5.0 ppm, phosphate-0.02mg/l, chloride-250mg/l, sulphate-250mg/l and nitrate-5.0 mg/l. After the comparison, our results showed that the contaminants were high in the three sample stations, meaning that these dumpsites may affect the quality of the water both for domestic and other purposes. Based on the findings, therefore, the government should enact laws to safeguard aquatic lives and the health of individuals who depend on the water as a major source for domestic use. Adequate sensitization by the use of visual aid and local dialect would help educate the community on the dangers of contaminated water and the adverse health effects. Also, dumpsites should be situated far-off from rivers and residential buildings, as this will prevent a major outbreak of diseases that may be detrimental to human health.
Advanced Science Letters, 2013
The use of landfill as a major waste disposal option is very predominant in most developing nations; hence most landfills or dump sites that abound in such places are termed "active" since they still receive MSW. However, the developed and developing nations still have closed landfills which are termed as "non-active". Whole effluent (leachate) that is produced from dumping of waste becomes a subject of concern considering the potential impact on the environment. This study emphasized on the characterized discrete components of leachate from both active and non-active landfills with view of using bioassay to show their varying degree of toxicity on aquatic life.