Phosphate treatment by onsite wastewater systems in nutrient-sensitive watersheds of North Carolina's Piedmont

2016 ◽  
Vol 74 (7) ◽  
pp. 1527-1538 ◽  
Author(s):  
Charles Humphrey ◽  
Brent Serozi ◽  
Guy Iverson ◽  
Jordan Jernigan ◽  
Sushama Pradhan ◽  
...  
Keyword(s):  
Surface Waters ◽  
Surface Water Quality ◽  
Environmental Parameters ◽  
Additional Treatment ◽  
Single Pass ◽  
The North ◽  
Onsite Wastewater ◽  
Mass Load ◽  
Wastewater Systems ◽  
Phosphate Treatment

The goal of this study was to gain a better understanding of the PO4-P treatment efficiency of onsite wastewater systems (OWS) installed in nutrient-sensitive watersheds of the North Carolina Piedmont. Four OWS including two conventional and two single-pass sand filter (SF) systems were evaluated at sites with clay-rich soils. Piezometers were installed near all of the OWS, and down-gradient from the conventional OWS for groundwater collection and characterization. Septic tanks, groundwater, SF effluent, and surface waters were sampled each season during 2015 (five times) and analyzed for PO4-P and Cl concentrations and for various environmental parameters. The conventional and SF OWS reduced PO4-P concentrations by an average of 99% and 90%, respectively, before discharge to surface waters. Mass-load reductions of PO4-P were also greater for the conventional OWS (mean 95%), relative to SF (83%) systems. The effluents discharged by SF OWS were influencing surface water quality. Additional treatment of the effluent from single-pass SF with reactive media is suggested, along with monitoring of the final effluent for PO4-P concentrations. This research provides important information that is absent from the published literature concerning PO4-P contributions to water resources from OWS in clay soils.

scholarly journals MONITORING ASSESSMENT OF THE SURFACE WATER QUALITY WITHIN THE AREAS FOR THE MUNICIPAL SOLID WASTE DISPOSAL

2020 ◽  
pp. 56-60
Author(s):  
O. Azimov ◽  
I. Kuraeva ◽  
O. Trofymchuk ◽  
K. Zlobina ◽  
S. Karmazynenko
Keyword(s):  
Surface Water ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Waste Disposal ◽  
Surface Waters ◽  
Surface Water Quality ◽  
Adjacent Area ◽  
Solid Waste Disposal ◽  
The North ◽  
North Western

The monitoring ecological hydro-geochemical investigations for the surface waters of the north-western part of Landfill No 5 for the municipal solid waste disposal and the adjacent area are carried out. Based on analyses of surface water samples taken from the existing ponds, it was found that they are polluted by wastewater with the high content of predominantly organic toxicants. Most likely the latter comes from both the Sections and ponds-collectors of leachate or from the pig farm, which is located near the Landfill but hypsometrically higher in relief. More studies are required in order to specify the answer. On the other hand, surface waters beyond the Landfill area are characterized by the ecological and hydrogeochemical indicators, which are not higher than the maximum allowable concentrations, although they are higher than the background ones. This indicates that the considerable outflow of chemical pollutants together with the surface waters from the north-western Landfill No 5 area beyond its borders is absent for more than a year. Only the short-time periodic monitoring of the water bodies within the territory of interest would allow to determine such time intervals when water could be polluted by various toxicants.

scholarly journals Comparison of Nitrogen Treatment by Four Onsite Wastewater Systems in Nutrient-Sensitive Watersheds of the North Carolina Coastal Plain

Nitrogen ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 268-286
Author(s):  
Charles P. Humphrey ◽  
Michael O’Driscoll ◽  
Guy Iverson
Keyword(s):  
North Carolina ◽  
Permeable Reactive Barriers ◽  
Wastewater Remediation ◽  
Treatment Efficiency ◽  
The North ◽  
Onsite Wastewater ◽  
Lack Of Information ◽  
Remediation Strategies ◽  
Wastewater Systems ◽  
N Treatment

Wastewater may be a source of nitrogen (N) to groundwater and surface waters if not effectively treated. In North Carolina, onsite wastewater systems (OWSs) are used by 50% of the population for wastewater treatment, but most OWSs are not routinely monitored. There is a lack of information regarding the N contributions from OWSs to water resources. Four sites with OWSs were instrumented with groundwater wells near their drainfield trenches to compare N concentrations in groundwater to concentrations in wastewater and to determine the N treatment efficiency of the systems. Two OWSs (Site 200 and 300) were less than 1 year old, and two (Site 100 and 400) were more than 10 years old at the start of the study. Two OWSs (Site 100 and 200) used pressure dosing, while two OWSs (Site 300 and 400) used gravity distribution. The mean N treatment efficiency of the four OWSs was 77%. The new OWSs were more efficient (92%) relative to the older OWSs (62%) at reducing N concentrations. Similar N treatment efficiencies were observed when pooling data for the pressure dosed (77%) and gravity (79%) OWSs. Each OWS influenced groundwater by causing increases in N concentrations. It is important that new OWSs are installed at a shallow depth and with sufficient separation to groundwater to promote the aerobic treatment of wastewater. Remediation strategies including the installation of permeable reactive barriers or the use of media filters may be needed in some areas to reduce N transport from existing OWS.

Phthalate Esters and Other Industrial Organic Chemicals in the North and Irish Seas

1991 ◽  
Vol 24 (10) ◽  
pp. 127-134 ◽  
Author(s):  
R. J. Law ◽  
T. W. Fileman ◽  
P. Matthiessen
Keyword(s):  
Surface Waters ◽  
Phthalate Esters ◽  
Organic Chemicals ◽  
Ion Detection ◽  
Ecotoxicological Assessment ◽  
Industrial Activities ◽  
The North ◽  
Detection Mode

Concentrations of a range of industrial organic chemicals (xylene, styrene, chlorobenzene and five phthalate esters) have been determined in surface waters near the Humber, Mersey, Tamar, Tees and Tyne estuaries. Analyses were conducted using GC/MS in the multiple ion detection mode. In general, the highest concentrations (in the ng to µg dm−3 range) for all determinands were found at sites within the estuaries. Selected samples were also analysed by scanning GC/MS and other compounds tentatively identified. There was only minor overlap between the compounds found at each of the estuaries, presumably a reflection of the industrial activities in the area. A preliminary ecotoxicological assessment was made of both datasets.

scholarly journals Modelling the flow of nitrogen and phosphorus in Europe: from loads to coastal seas

1995 ◽  
Vol 31 (8) ◽  
pp. 141-145 ◽  
Author(s):  
A. H. W. Beusen ◽  
O. Klepper ◽  
C. R. Meinardi
Keyword(s):  
Surface Water ◽  
Western Europe ◽  
Human Impacts ◽  
Water Discharge ◽  
Surface Water Quality ◽  
Nitrogen And Phosphorus ◽  
The North ◽  
Surface Water Flow ◽  
The Baltic ◽  
Parameter Values

A model is described that aims at predicting surface water quality from N- and P-inputs on a European scale. The model combines a GIS-based approach to estimate loads, geohydrological data to define model structure and statistical techniques to estimate parameter values. The model starts with an inventory of sources of N and P: agriculture, wastewater and (for N) atmospheric deposition. Nitrogen flows are assumed to follow both surface- and groundwater flows, while for phosphorus only surface water flow is taken into account. A calibration of loss terms of N and P (assumed to be constants for the whole of Europe) by comparing total inputs to measured loads shows good agreement between observations and calculated river discharges. For the coastal seas of Europe concentrations are calculated by assuming conservative behaviour of N and P. Freshwater quality problems occur in western Europe with its intensive agriculture and high population density and locally in southern Europe where dilution is low due to low water discharge. In the marine environment the main problem areas are the Baltic and Black seas, with much lower impacts in the North and Adriatic Sea; in other coastal waters human impacts are essentially negligible.

scholarly journals The circulation of the surface waters of the North Atlantic Ocean

1900 ◽  
Vol 66 (424-433) ◽  
pp. 484-485
Keyword(s):  
Atlantic Ocean ◽  
North Atlantic ◽  
Surface Waters ◽  
North Atlantic Ocean ◽  
The North ◽  
The North Atlantic

In this paper an attempt is made to investigate the normal circulation of the surface waters of the Atlantic Ocean north of 40° N. lat., and its changes, by means of a series of synoptic charts showing the distribution of temperature and salinity over the area for each month of the two years 1896 and 1897.

Climate Response to External Sources of Freshwater: North Atlantic versus the Southern Ocean

2007 ◽  
Vol 20 (3) ◽  
pp. 436-448 ◽  
Author(s):  
Ronald J. Stouffer ◽  
Dan Seidov ◽  
Bernd J. Haupt
Keyword(s):  
Southern Ocean ◽  
Southern Hemisphere ◽  
North Atlantic ◽  
Surface Waters ◽  
Real World ◽  
The Other ◽  
Sea Surface ◽  
The North ◽  
The North Atlantic ◽  
The Antarctic

Abstract The response of an atmosphere–ocean general circulation model (AOGCM) to perturbations of freshwater fluxes across the sea surface in the North Atlantic and Southern Ocean is investigated. The purpose of this study is to investigate aspects of the so-called bipolar seesaw where one hemisphere warms and the other cools and vice versa due to changes in the ocean meridional overturning. The experimental design is idealized where 1 Sv (1 Sv ≡ 106 m3 s−1) of freshwater is added to the ocean surface for 100 model years and then removed. In one case, the freshwater perturbation is located in the Atlantic Ocean from 50° to 70°N. In the second case, it is located south of 60°S in the Southern Ocean. In the case where the North Atlantic surface waters are freshened, the Atlantic thermohaline circulation (THC) and associated northward oceanic heat transport weaken. In the Antarctic surface freshening case, the Atlantic THC is mainly unchanged with a slight weakening toward the end of the integration. This weakening is associated with the spreading of the fresh sea surface anomaly from the Southern Ocean into the rest of the World Ocean. There are two mechanisms that may be responsible for such weakening of the Atlantic THC. First is that the sea surface salinity (SSS) contrast between the North Atlantic and North Pacific is reduced. And, second, when freshwater from the Southern Ocean reaches the high latitudes of the North Atlantic Ocean, it hinders the sinking of the surface waters, leading to the weakening of the THC. The spreading of the fresh SSS anomaly from the Southern Ocean into the surface waters worldwide was not seen in earlier experiments. Given the geography and climatology of the Southern Hemisphere where the climatological surface winds push the surface waters northward away from the Antarctic continent, it seems likely that the spreading of the fresh surface water anomaly could occur in the real world. A remarkable symmetry between the two freshwater perturbation experiments in the surface air temperature (SAT) response can be seen. In both cases, the hemisphere with the freshwater perturbation cools, while the opposite hemisphere warms slightly. In the zonally averaged SAT figures, both the magnitude and the pattern of the anomalies look similar between the two cases. The oceanic response, on the other hand, is very different for the two freshwater cases, as noted above for the spreading of the SSS anomaly and the associated THC response. If the differences between the atmospheric and oceanic responses apply to the real world, then the interpretation of paleodata may need to be revisited. To arrive at a correct interpretation, it matters whether or not the evidence is mainly of atmospheric or oceanic origin. Also, given the sensitivity of the results to the exact details of the freshwater perturbation locations, especially in the Southern Hemisphere, a more realistic scenario must be constructed to explore these questions.

Simple harpacticoid composition observed at deep hydrothermal vent sites on sea knoll calderas in the North-west Pacific

2022 ◽  
pp. 1-10
Author(s):  
Futa Nakasugi ◽  
Motohiro Shimanaga ◽  
Hidetaka Nomaki ◽  
Hiromi Kayama Watanabe ◽  
Tomo Kitahashi ◽  
...  
Keyword(s):  
Deep Sea ◽  
Hydrothermal Vent ◽  
Hydrothermal Vents ◽  
Environmental Parameters ◽  
Sea Floor ◽  
North West ◽  
Isotopic Signatures ◽  
Carbon Isotopic ◽  
The North ◽  
Spatial Differences

Abstract Dirivultid copepods (Siphonostomatoida), one of the most successful meiobenthic organisms found at deep-sea hydrothermal vents, have been the focus of most previous ecological studies among meiofauna in these habitats. The ecology of Harpacticoida, a major benthic copepod group in typical deep-sea floor, however, is not well understood in terms of variations in community structure and controlling factors at venting sites. The spatial heterogeneities in benthic harpacticoid composition and their association with environmental parameters were investigated at hydrothermal vent chimney structures in the calderas of three neighbouring sea knolls (Bayonnaise Knoll, Myojin Knoll and Myojin-sho Caldera) in the western North Pacific. While a previous study had reported the distribution of dirivultids was strongly associated with spatial differences in stable carbon isotopic signatures (δ13C) of organic matter in the detritus on active chimneys in the field, multivariate analyses detected no significant corelation between the parameter and harpacticoid composition in this study. Instead, high associations of the harpacticoid composition with differences in water depth and total organic carbon (TOC) concentration were detected. Ectinosomatidae dominated at vent sites with lower TOC values in the shallowest Bayonnaise Knoll, while they were less prevalent at deeper vent fields in the other knolls, where Miraciidae was the most abundant family. This study indicated the availability of vent chemoautotrophic carbon is not a primary factor controlling the composition of harpacticoids even in the habitats on the hydrothermal vents, but instead by the food amount, regardless of its resources (including marine snow from the sea surface), in the study area.

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