Total Extractable Hydrocarbons Research Articles

Intrinsic bioremediation of diesel-contaminated cold groundwater in bedrock

In 1982 diesel fuel migrated from a well lease site into underlying fractured bedrock contaminating the groundwater-bearing zone approximately 30 m below ground surface. Historical contaminant concentrations, geochemical indicators, and microbiological data were analysed to evaluate natural attenuation, specifically intrinsic bioremediation. Evidence of microbial activity was provided by most probable number (MPN) and commercial biological activity reaction tests (BART™). Laboratory microcosms using groundwater from the site were incubated under aerobic and anaerobic conditions with electron acceptor and nutrient amendment to assess microbial activity. Aerobic biodegradation rates were determined by measuring mineralization of 14C-dodecane. Nutrient amendment combined with a higher temperature (28 °C) increased the first-order aerobic biodegradation rate to 0.0066 d–1 from 0.0002 d–1 at 10 °C. Anaerobic biodegradation rates were calculated from depletion of total extractable hydrocarbons (TEH) over 717 d at 10 °C. Nutrient addition increased the anaerobic first-order biodegradation rate to 0.0016 from 0.0005 d–1. Data from these laboratory microcosms indicate that the current slow rates of intrinsic bioremediation may be enhanced with nutrient addition. Key words: intrinsic bioremediation, natural attenuation, groundwater, diesel fuel, hydrocarbon biodegradation, anaerobic hydrocarbon biodegradation, biological activity reaction test (BART™).

Extractable Hydrocarbons, Nickel and Vanadium Contents of Ogbodo-Isiokpo Oil Spill Polluted Soils in Niger Delta, Nigeria

An oil spill polluted site at Ogbodo-Isiokpo in Ikwere Local Government Area of Rivers State in southern Nigeria, was identified for study following three successive reconnaissance surveys of oil fields in the Agbada west plain of Eastern Niger Delta. A sampling area of 200 m x 200 m was delimited at the oil spill impacted site using the grid technique and soils were collected at surface (0-15 cm) and subsurface (15-30 cm) depths from three replicate quadrats. A geographically similar, unaffected area, located 50 m adjacent to the polluted site, was chosen as a control (reference) site. Total extractable hydrocarbon contents of the polluted soils ranged from 3.02-4.54 and 1.60-4.20 mg/kg (no overlap in standard errors) at surface and subsurface depths respectively. The concentrations of two "diagnostic" trace heavy metals, nickel (Ni) and vanadium (V), which are normal constituents of crude oil, were also determined in the soils by atomic absorption spectrophotometric method after pre-extraction of cations with dithionite-citrate carbonate. Ni varied from 0.15 to 1.65 mg/kg in the polluted plots and from 0.18 to 0.82 mg/kg in the unpolluted plots; vanadium varied from 0.19 to 0.70 mg/kg in the polluted plots and from 0.14 to 0.38 mg/kg in the unpolluted plots. Ni and V were more enhanced (p < 0.05) in the oil-polluted soils, especially at subsurface depth. Whilst the oil spillage could be said to be indirectly responsible for the enhanced concentrations of nickel and vanadium via the injection and availability of the petroleum hydrocarbons that might have increased the activities of biodegradation on site, the physico-chemical properties of the soils and inherent mobility of metals, as well as the intense rainfall and flooding that characterized the period of study, may have also contributed, at least in part, to these enhanced concentrations. Such levels of Ni and V may result to enhanced absorption by plants, which may bring about possible bioaccumulation in such plants and the animals that depend on them for survival and all of these may lead to toxic reactions along the food chain.

Post‐Impact Assessment of Oil Pollution in Agbada West Plain of Niger Delta, Nigeria: Field Reconnaissance and Total Extractable Hydrocarbon Content

Typical post-impact assessment of an oil-spill-impacted site in Agbada west plain of the Niger Delta basin of Nigeria was carried out 13 months after recorded incidence of spillage, using empirical indices of reconnaissance and extractable hydrocarbon content. Field-reconnaissance surveys revealed lower species' numbers and diversity of surface and subterranean flora and fauna. The presence and absence of such plant species as Elaeis guineensis, Musanga cecropiodes, and Andropogon gayanus, as well as animal species like earthworms and nematodes in sampled plots, corroborated the evidence provided by the total extractable hydrocarbon content (of (2.53+/-0.43)x10(2) mg/kg and (2.00+/-0.76)x10(2) mg/kg at surface and subsurface depths, resp.) on the level of degradation and/or regeneration at the polluted site. The most important evidence that oiling must have been responsible, at least in part, for the reduction in species' number and diversity was provided by the plant cover, Andropogan gayanus, which occurred at a lower density of 0.9 plants/m2 in the oil-impacted plots and 14.00 plants/m2 in the unimpacted reference plots of an adjacent, geographically similar area. The presence of this species on site thus presented a significant difference (P<0.05) of over 85%, and indicated exhaustion or impoverishment of impacted soils. Elaeis guineensis, with a population density of 0.1 stands/m2, provided evidence of past cultivation on site, while species like Musanga cecropioides, with a density of 0.5 stands/m2, at the unimpacted site, confirmed the abandonment of the farmstead over a long period of time. For the fauna, the most sensitive indicator of hydrocarbon toxicity was provided by nematode Xiphinema sp. that were completely absent in the oil-impacted site.

Characterization of PAH Sources in Sediments of the Thea Foss/Wheeler Osgood Waterways, Tacoma, Washington

The character of polycyclic aromatic hydrocarbons (PAH) in sediments of the Thea Foss and Wheeler-Osgood Waterways in Tacoma, Washington, were investigated with the objective of determining the general source(s) of these compounds to the waterways. In this study, 42 near-surface sediment samples from the Waterways were collected and analyzed for their (1) concentration of 43 individual or groups of PAH, (2) total extractable hydrocarbon “fingerprint” and concentration, (3) grain size and (4) total organic carbon content. Analysis of the sediment data, including comparisons to standard reference materials, indicates that all but two samples contained PAH derived from a pyrogenic source(s), i.e., a non-petroleum source(s). The high concentrations and characteristic distributions of PAH in some sediment samples were consistent with the occurrence of manufactured gas plant (MGP) derived tar(s) or tar distillate(s), particularly in some sediments proximal to a historic MGP and tar distillate storage operation near the head of the Thea Foss Waterway. Most other sediment samples throughout the Waterways contained PAH distributions and concentration indicating (at least) a greater proportion of PAH are derived from urban runoff/fallout.

Treatability Testing of Intrinsic Bioremediation, Biostimulation, And Bioaugmentation of Diesel-oil Contaminated Soil At 5 ° C

Abstract To support the remediation design for a diesel-oil pipeline break near a remote railway river crossing near the British Columbia and Alaska border, a treatability test was designed to assess the in-situ bioremediation potential under four conditions of soil amendments at 5 ° C. The four conditions were:intrinsic bioremediation, where the soil received only water;biostimulation with one application of slow-release fertilizer;bioaugmentation with one application of both fertilizer and a psychrotrophic (cold-adapted), hydrocarbon-degrading bacterial culture; andsurfactant enhanced bioavailability, where the soil received one application of fertilizer and treatment with a biodegradable surfactant solution. Tests were monitored by soil respiration and bacterial enumeration and total extractable hydrocarbon (TEH) content by GC/FID. After 40 days incubation under aerobic conditions, all tests showed significant reduction in diesel range (C7 - C30) THE contamination. The intrinsic control was least effective, but still showed 66% TEH reduction at 5 ° C. The biostimulated soil performed the best, allowing 86% TEH reduction. The bioaugmented soil and surfactant treated soil both allowed about 75% TEH reduction. The study concluded that simple biostimulation with slow-release fertilizers would be the most appropriate bioremediation approach for this site. Introduction A four-inch diameter petroleum pipeline, located adjacent to the rail tracks of the White Pass and Yukon Route Railroad, was broken by heavy equipment working in the area in October 1994. A significant quantity of Arctic diesel fuel leaked and immediate efforts were made to recover most of the product through the summer of 1995. Following site investigation in November 1995, a plume of diesel contamination was delineated in the gravelly cobbles and boulder fill supporting the railway bridge over the East Fork Skagway River. The plume had migrated downward through the fill to bedrock surface. Liquid product at the toe of the slope could discharge with shallow groundwater flow over ground surface into the river. The estimated 500 m3 of residual hydrocarboncontaminated fill supporting the railway bed required remediation to prevent continued contamination of the water passing through the contaminated area. Initial soil chemical and biological data indicated that active natural biodegradation of petroleum hydrocarbons may be occurring at the site, but appears limited by natural nutrient level and the indigenous bacterial population at the site. The gravelly soil near the toe of the slope contains between 1,000 and 5,000 mg/kg of total extractable hydrocarbons (TEH) and has an indigenous heterotrophic bacteria population of between 104 and 106 bacteria/ g of soil. Excavation of the slope and structural fill supporting the operating railway was not feasible; therefore, in-situ remediation options were considered. Because of the generally low volatility of some components of Arctic diesel and the lack of electrical power at the remote site, in-situ bioremediation was considered the most feasible option. To determine the optimal conditions for in-situ bioremediation of this hydrocarbon-contaminated soil, a laboratory-scale treatability study was carried out. Because of the cold climate near the Alaska-British Columbia border, it was imperative that the testing be performed at the expected ambient soil temperature of about 5 to 8 ° C.

Toxicological evaluation of hydrocarbon removal from soils by an extraction and solubilization remediation process

Toxicity analyses were performed on manufactured frac sands and construction fill material to assess the efficacy of a pilot scale treatment system designed to remediate environments impacted with organic contaminants. Oiled proppants and backfill were collected from the North Slope in Alaska while unadulterated fill material from the Idaho National Engineering Laboratory (INEL) was collected and then contaminated with crude oil. Two commercial bioassays (Microtox, Polytox) were used to provide toxicological data for process waters, and treated and untreated solids from the soils treatment system. Total extractable hydrocarbon analyses were performed on treated and untreated solids, and indicated removal efficiencies greater than 95% for all samples tested. Microtox testing using sonicated extracts from solids and whole water samples provided the most sensitive and useful toxicological data, showing the soil treatment system to significantly reduce the toxicity of treated solids.

Mineralization of polycyclic and N‐heterocyclic aromatic compounds in hydrocarbon‐contaminated soils

AbstractThe comparative mineralization of eight polycyclic aromatic compounds in five soils collected from an abandoned coal tar refinery in eastern Ohio was determined. The soils showed differences only in total extractable hydrocarbon content of the soil chemical characteristics measured. The compounds studied included five polycyclic aromatic hydrocarbons (phenanthrene, anthracene, pyrene, and carcinogenic benz[a]anthracene and benzo[a]pyrene) and three N‐heterocyclic aromatics (9H‐carbazole, and carcinogenic 7H‐dibenzo[c,g]carbazole and dibenz[a,j]acridine). Mineralization was measured by serum bottle radiorespirometry. Only phenanthrene, anthracene, pyrene, benz[a]anthracene, and carbazole were mineralized in the soils after 64 d. Two of the soils with eight to 15 times the hexane‐extractable hydrocarbon content consistently showed more rapid initial rates and higher overall extents of mineralization compared to the other three soils. Overall extents of mineralization ranged from 38 to 55% for phenanthrene, 10 to 60% for anthracene, 25 to 70% for pyrene, background to 40% for benz[a]anthracene, and 25 to 50% for carbazole after 64 d. Extents of mineralization by indigenous soil microbiota appear to be more dependent on the chemical characteristics of the soil and not soil total biomass and activity. Cultures capable of degrading phenanthrene, anthracene, and pyrene were obtained following enrichment techniques. A Mycobacterium sp. capable of degrading these three compounds was isolated and reintroduced into two of the soils, resulting in mineralization enhanced above that of the indigenous soil microbial population. These data indicate that the future success of bioremediation methods relies on the characterization of environmental parameters affecting microbial degradation as well as the isolation of microbial populations that can reduce toxicity in the environment.

Polycyclic aromatic hydrocarbon and petroleum hydrocarbon contamination in sediment from the Newark Bay estuary, New Jersey

The presence of numerous industrial and municipal sources such as former creosote wood preserving facilities, petroleum storage and refinery facilities, paint and chemical manufacturers, combined sewer overflows, and sewage treatment facilities along the shores of Newark Bay, New Jersey and its major tributaries suggests the potential for widespread contamination by polycyclic aromatic hydrocarbons (PAHs) and petroleum hydrocarbons. In this study, the concentrations and distributions of 19 PAHs and total extractable petroleum hydrocarbon (TEPH) were determined in 213 sediment samples obtained from 58 sediment cores collected between November 1991 and March 1993 from the Arthur Kill, Elizabeth River, Hackensack River, Kill Van Kull, Newark Bay, Upper New York Bay, and Rahway River. Chronological profiles of PAH and TEPH deposition from pre-1930 to the present were determined in each sediment core using 137Cs and 210Pb radioisotope measurements. The concentrations of total PAHs (tPAH) and individual PAHs were compared to National Oceanic and Atmospheric Administration (NOAA) benchmark sediment effects-range median (ER-M) values. The objectives of this study were to: (a) determine the spatial and temporal distributions of PAHs in sediments; (b) identify their possible sources; and (c) assess the potential for sediment toxicity within the estuary. The results indicate elevated concentrations of PAHs and TEPH in surface and buried sediments throughout the estuary, particularly in the Elizabeth River, the Arthur Kill, and in the Passaic River above the Dundee Dam and below the Jackson Street Bridge. Sediments collected from ship berths at Port Newark and Port Elizabeth in Newark Bay were also found to contain elevated levels of PAHs and TEPH. The concentrations of PAHs and TEPH in sediment generally increase with depth throughout the estuary. Comparisons to NOAA ER-M values indicate that the concentrations of many PAHs in surface and buried sediments at several locations in the estuary pose a significant hazard to aquatic organisms. Radiodating of sediment cores reveals that the highest concentrations of PAHs, and the greatest potential hazards to aquatic biota, occur in sediments deposited during the 1950s. Although the major inputs of PAHs are probably combustion sources and urban runoff entering the estuary through combined sewer overflows and storm drains, the unusually high concentrations of PAHs and TEPH found in some sediments may be best explained by point source inputs or catastrophic oil spills.

Thermogravimetry of filter-borne diesel particulates

A direct thermogravimetric (TG) method is described for determining the percentage of volatile components in filter-borne diesel particulates. The procedure gives a quick estimate of total solvent extractable hydrocarbon components. A silica gel fractionation/size exclusion Chromatographic (SGF/SEC) procedure has also been developed to analyze further the solvent-extractable hydrocarbons of the particulates. The solvent extraction SGF/SEC procedure determines the contribution of lubricating oil and unburned fuel to particulates emitted from diesel engines. Results from this study indicate that the TG method yields a comparable measure of adsorbed hydrocarbons with those obtained by solvent extraction.

Mierobial biogeochemistry and heterotrophy in sediments of a marine hydrocarbon seep

Vertical profiles of sediment and pore‐water constituents and rates of microbially mediated geochemical processes were determined in surficial sediments (0–7‐cm depth) of three stations in and around Isla Vista hydrocarbon seep off Santa Barbara, California. Measurements were made of pore‐water alkalinity (total and carbonate), pH, Eh, dissolved oxygen, sulfate, and sulfide, total sedimentary organic carbon (TOC) and nitrogen, ATP, sulfate reduction and dark bicarbonate uptake and incorporation, and oxygen flux across the sediment‐water interface in benthic chambers.In general, alkalinity, pH, sulfide, TOC, ATP, and all rate processes were greatest in sediments of that station (A) with active seepage and decreased with increasing distance from the seep. Sulfate depletion and extremely low Eh values occurred in station A sediments. At a station (B) with lower seepage rates than station A, sedimentary and pore‐water constituents and rate processes were intermediate to those measured at station A and a station (C) without seepage. Pore‐water and sedimentary constituents as well as oxygen flux were strongly correlated with total extractable sedimentary hydrocarbons (TEH) measured at each station and for each corresponding depth interval. All parameters exhibited seasonal differences that may have been temperature‐dependent.The greater concentrations of TEH, sulfide, and alkalinity with increasing sedimentary depth indicate that seep sediments are a source of these constituents to the water column and a sink for O2 and SO42‒. The strong heterotrophic, and possibly chemoautotrophic, character of seep sediments resembles that of other organically enriched systems. The diagenesis of petroleum hydrocarbons is a function of the biogeochemical patterns and microbial heterotrophic activities in surficial sediments.

Degradation of soil applied organic compounds from three petroleum wastes

The degradation rates of three industrial wastes were evaluated under simulated land treatment conditions. A wood-preserving bottom sediment, storm-water runoff impoundment sludge, and combined API-separator/slop-oil emulsion solid waste were applied to greenhouse boxes containing Norwood silt loam or Bastrop clay soils. Soil samples were collected before waste application and 0, 180, 360 and 540 days following application. Solvent extractable organic compounds were determined gravimetrically, and a GC/MS/DS system was used to identify major extractable organic constituents. The most rapid degradation rate over a 360 day period was observed in the Bastrop soil amended with the combined API separator/slop-oil emulsion solid waste. The half-lives of the total extractable hydrocarbons ranged from a low of 217 days for the combined API waste in the Bastrop soil to a high of 340 days for the storm-water runoff waste in the Norwood soil. Major residual organic constituents in the waste amended soil after 60 days incubation included pentachlorophenol, fluoranthene, pyrene, dihydro acenaphthylene, cyclopenta phenanthrene and trimethyl naphthalene. These results indicate that large quantities of oil hydrocarbons can be degraded by soil application, and significant differences in degradation rates will occur between different wastes and soils.

Degradation of Soil Applied Organic Compounds From Three Petroleum Wastes

The degradation rates of three industrial wastes were evaluated under simulated land treatment conditions. A wood-preserving bottom sediment, storm-water runoff impoundment sludge, and combined API-separator/slop-oil emulsion solid waste were applied to greenhouse boxes containing Norwood silt loam or Bastrop clay soils. Soil samples were collected before waste application and 0, 180, 360 and 540 days following application. Solvent extractable organic compounds were determined gravimetrically, and a GC/MS/DS system was used to identify major extractable organic constituents. The most rapid degradation rate over a 360 day period was observed in the Bastrop soil amended with the combined API separator/slop-oil emulsion solid waste. The half-lives of the total extractable hydrocarbons ranged from a low of 217 days for the combined API waste in the Bastrop soil to a high of 340 days for the storm-water runoff waste in the Norwood soil. Major residual organic constituents in the waste amended soil after 60 days incubation included pentachlorophenol, fluoranthene, pyrene, dihydro acenaphthylene, cyclopenta phenanthrene and trimethyl naphthalene. These results indicate that large quantities of oil hydrocarbons can be degraded by soil application, and significant differences in degradation rates will occur between different wastes and soils.

Fate of Hydrocarbons During Oily Sludge Disposal in Soil

A 1,280-day laboratory simulation of the "landfarming" process explored the fate in soil of polynuclear aromatics (PNAs) and total extractable hydrocarbon residues originating from the disposal of an oily sludge. In addition to the measurement of CO(2) evolution, periodic analyses of PNAs and hydrocarbons monitored biodegradation activity. The estimation of carbon balance and of soil organic matter assessed the fate of residual hydrocarbons. Seven sludge applications during a 920-day active disposal period were followed by a 360-day inactive "closure" period with no further sludge applications. A burst of CO(2) evolution followed each sludge addition, but substantial amounts of undegraded hydrocarbons remained at the end of the study. Hydrocarbon accumulation did not inhibit biodegradation performance. Conversion of hydrocarbons to CO(2) predominated during active disposal; incorporation into soil organic matter predominated during the closure period. In this sludge, the predominant PNAs were degraded more completely (85%) than total hydrocarbons. Both biodegradation and abiotic losses of three- and four-ring PNAs contributed to this result. Some PNAs with five and six rings were more persistent, but these constituted only a small portion of the PNAs in the sludge. The study confirmed that the microbially mediated processes of mineralization and humification remove sludge hydrocarbons from soils of landfarms with reasonable efficiency.

Petroleum Geochemistry and Geology of Cenozoic and Mesozoic Sedimentary Rocks from Georges Bank Basin: ABSTRACT

On the basis of petroleum geochemical studies of the COST G-1 and G-2 well samples in the George Bank Basin, the Tertiary and Cretaceous sections between depths of 0 and 6,000 ft (1,829 m) are not believed to be prospective for oil or gas because of the thermally immature character of the lignitic and woody type of kerogens and extractable organic matter. The total organic carbon and extractable hydrocarbons of the Jurassic sedimentary rocks below 6,000 ft (1,829 m) indicate that these are poor to fair source rocks. Compositions of the C1 to C7 light and gasoline-range hydrocarbons, temperatures of maximum pyrolysis (TS2)°C, carbon preference indices (CPI), and thermal alteration indices (TAI) suggest that the shallowest thermally mature rocks are between 16,000 and 18,000 ft (4,877 and 5,486 m) in the G-2 well. High vitrinite reflectance (Ro) percentages may reflect oxidation and recycled organic matter. Estimates of the depth of thermal maturity based on measurements of the present geothermal gradient at the G-1 (1.2°F/100 ft) and G-2 (1.5°F/100 ft) wells are inconsistent with the depth of thermal maturity indicated by temperature-sensitive geochemical characteristics. The results of this study suggest that further consideration should be given to: (1) a reassessment of thermal-maturation processes in sediments associated with rift basins on passive margins; (2) the possibility that thermal maturation of the organic matter in the basin may have been influenced by a variable heat-flow history; (3) the location of the heat source, which may have been farther east of the present continental shelf than is presently thought. End_of_Article - Last_Page 1667------------

Structure and Hydrocarbon Potential of Kodiak Shelf, Alaska: ABSTRACT

The Albatross basin underlies the southwest one-third of the Kodiak shelf, Alaska, and contains about 5 km of gently to moderately deformed rocks that are as old as late Miocene or Pliocene. The seaward limit of the basin is a large, northeast-trending anticline that underlies the shelf break. The Dangerous Cape high, northeast of Albatross basin, is distinguished from the basin by shallow depth (1 to 2 km) to the base of reflective strata, by decreased relief of structures that underlie the shelf break, and by the central-shelf uplift. This uplift lies midway between Kodiak Island and the shelf break and is made up of several anticlines cut by numerous, northeast-trending reverse faults. Based on seismic evidence, deformed, nonreflective Paleogene rocks are inferred to unconformably underlie the less deformed upper Miocene or Pliocene reflective rocks. Stevenson basin, northeast of the Dangerous Cape high, includes two subbasins that are separated by the northwest-trending Portlock anticline. The southwest subbasin contains as much as 4 km of rocks, and the northeast subbasin contains as much as 5 to 7 km. End_Page 706------------------------------ Rocks that fill both subbasins are probably as old as late Miocene or Pliocene and are gently deformed, except near the Portlock anticline and near the shelf-break uplift. If hydrocarbon-source characteristics of rocks offshore are similar to those of rocks onshore, good hydrocarbon source rocks do not underlie the shelf. Eocene through middle Miocene rocks onshore, and upper Miocene or Pliocene rocks offshore, contain less than 0.5 wt % organic carbon, which is predominantly of herbaceous and humic orgin. The volume of total extractable hydrocarbons (C15+ Soxhlet extraction) from onshore Eocene through Miocene rocks ranges from 165 to 412 ppm. Offshore upper Miocene and Pliocene strata are thermally immature. Paleogene rocks, which are thermally mature, are the most likely sources for any hydrocarbons generated offshore, although indications are that they are low-quality sources. Onshore Paleogene rocks generally have poor reservoir properties--porosities range from 1 to 10% but most are less than 5%, and permeabilities are less than 1 md. The best offshore reservoirs are probably in late Miocene and younger strata. Structural traps for hydrocarbons include Portlock anticline, anticlines in the central-shelf uplift, and parts of Albatross Bank. End_of_Article - Last_Page 707------------