Chemical fate and transport in a domestic septic system: Unsaturated and saturated zone geochemistry

Wilhelm, Sheryl R.; Schiff, Sherry L.; Robertson, W. D.

doi:10.1002/etc.5620130203

Cited by 57 publications

(35 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In contrast to this system was the septic system in Canada that always has an unsaturated soil zone of at least 2 m and showed removal of LAS within 5 cm of the soil beneath the drainfield [14][15][16][17][18]. In contrast to this system was the septic system in Canada that always has an unsaturated soil zone of at least 2 m and showed removal of LAS within 5 cm of the soil beneath the drainfield [14][15][16][17][18].…”

Section: Ste Monitoringmentioning

confidence: 94%

“…Details * To whom correspondence may be addressed (adecarvalho@sdahq.org). As part of this work, LAS was shown to be effectively removed within 5 cm of soil below the drainfield [14][15][16][17][18]. Since these surfactants are used primarily in cleaning and personal care products, their usual route of disposal is down the drain to publicly owned treatment works (POTWs) or OWTS, resulting in their wide dispersal.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Investigation of an Onsite Wastewater Treatment System in Sandy Soil: Site Characterization and Fate of Anionic and Nonionic Surfactants

Nielsen¹,

Decarvalho²,

McAvoy³

et al. 2002

Environ Toxicol Chem

View full text Add to dashboard Cite

This study reports on the fate of linear alkylbenzene sulfonate (LAS), alcohol ethoxylate (AE), and alcohol ether sulfate (AES) surfactants in a home septic system near Jacksonville (FL, USA) that has been used since 1976. The drainfield at this site resides in fine sand (< 6% silt and clay) with an unsaturated zone that ranges from 0 to 1.3 m. During the wettest times of the year, it is likely that effluent from the septic system passes directly into the groundwater without exposure to an unsaturated zone of soil. Groundwater was collected during two sampling events, representing seasonal high and low groundwater table levels, and analyzed for the surfactants LAS, AES, and AE. During the wet season, the unsaturated zone was approximately 0.01 m beneath the drainfield. During the dry season, the unsaturated zone was about 0.4 m below the drainfield. Alcohol ethoxylate was not detected in any groundwater samples during either sampling. Alcohol ether sulfate was not found in the dry season sampling, but traces of AES had migrated downgradient about 4.7 m horizontally and 1.8 m vertically in the wet season. Linear alkylbenzene sulfonate was detected in some dry season samples and had moved downgradient some 11.7 m horizontally and 3.7 m vertically in the wet season. These observations demonstrate that these surfactants were removed to a great extent; otherwise, they would have traveled more than 260 m downgradient, which is the calculated distance that a conservative tracer like bromide would have moved downgradient over the life of the system. The most likely removal mechanisms for these surfactants were biodegradation and sorption. Therefore, this study indicates that LAS, AE, and AES are readily removed from groundwater in soils below septic system drainfields even in situations with minimal unsaturated soil zones.

show abstract

Section: Ste Monitoringmentioning

confidence: 94%

Section: Introductionmentioning

confidence: 99%

Investigation of an Onsite Wastewater Treatment System in Sandy Soil: Site Characterization and Fate of Anionic and Nonionic Surfactants

Nielsen¹,

Decarvalho²,

McAvoy³

et al. 2002

Environ Toxicol Chem

View full text Add to dashboard Cite

show abstract

“…Urea-N delivery to aquatic systems can even occur via atmospheric deposition (Timperley et al 1985), although its contribution relative to other DON species is typically minor (<10%; Cornell et al 1998). In developed areas, urea-N is commonly found in wastewater treatment plant (WWTP) effluent (Cozzi et al 2014), and to a lesser extent, in septic system discharges (Wilhelm et al 1994). Along with commercial fertilizers, urea-N is typically present in the excreta of livestock (Livingston et al 1962), producing added concerns over the washoff of urea-N from manures to surface waters (Kibet et al 2016).…”

Section: Introductionmentioning

confidence: 99%

Urea Fluctuations in Stream Baseflow across Land Cover Gradients and Seasons in a Coastal Plain River System

Tzilkowski

Buda

Boyer

et al. 2018

J American Water Resour Assoc

View full text Add to dashboard Cite

Urea‐N is a component of bioavailable dissolved organic nitrogen (DON) that contributes to coastal eutrophication. In this study, we assessed urea‐N in baseflow across land cover gradients and seasons in the Manokin River Basin on the Delmarva Peninsula. From March 2010 to June 2011, we conducted monthly sampling of 11 streams (4 tidal and 7 nontidal), 2 wastewater treatment plants, an agricultural drainage ditch, and groundwater underlying a cropped field. At each site, we measured urea‐N, DON, dissolved organic carbon (DOC), total dissolved nitrogen (TDN), NO3−‐N, and NH4+‐N. In general, urea‐N comprised between 1% and 6% of TDN, with the highest urea‐N levels in drainage ditches (0.054 mg N/L) and wetland‐dominated streams (0.035–0.045 mg N/L). While urea‐N did not vary seasonally in tidal rivers, nontidal streams saw distinct urea‐N peaks in summer (0.038 mg N/L) that occurred several months after cropland fertilization in spring. Notably, the proportion of wetlands explained 78% of the variance in baseflow urea‐N levels across the Manokin watershed. In wetland‐dominated basins, we found urea‐N was positively related to water temperature and negatively related to DOC:DON ratios, indicating short‐term urea‐N dynamics at baseflow were more likely influenced by instream and wetland‐driven processes than by recent agricultural urea‐N inputs. Findings demonstrate important controls of wetlands on baseflow urea‐N concentrations in mixed land‐use basins.

show abstract

“…The majority of N treatment typically occurs in the soils as the effluent percolates through the unsaturated zone and most of the N is expected to convert to the nitrate form. In subsurface anaerobic environments that contain denitrifying bacteria and organic matter, denitrification can lower NO 3 − concentrations in soil water and groundwater (Wilhelm et al 1994a). Since OWTS wastewater is often discharged at depths of ~1 m in the subsurface, plant uptake and denitrification in the shallow organic soils is generally minimal (Gold and Sims 2001).…”

Section: Introductionmentioning

confidence: 99%

Meteorological Influences on Nitrogen Dynamics of a Coastal Onsite Wastewater Treatment System

et al. 2014

View full text Add to dashboard Cite

Onsite wastewater treatment systems (OWTS) can contribute nitrogen (N) to coastal waters. In coastal areas with shallow groundwater, OWTS are likely affected by meteorological events. However, the meteorological influences on temporal variability of N exports from OWTS are not well documented. Hydrogeological characterization and seasonal monitoring of wastewater and groundwater quality were conducted at a residence adjacent to the Pamlico River Estuary, North Carolina during a two-year field study (October 2009–2011). Rainfall was elevated during the first study year, relative to the annual mean. In the second year, drought was followed by extreme precipitation from Hurricane Irene. Recent meteorological conditions influenced N speciation and concentrations in groundwater. Groundwater total dissolved nitrogen (TDN) beneath the OWTS drainfield was dominated by nitrate during the drought; during wetter periods ammonium and organic N were common. Effective precipitation (P-ET) affected OWTS TDN exports because of its influence on groundwater recharge and discharge. Groundwater nitrate-N concentrations beneath the drainfield were typically higher than 10 mg/l when total bi-weekly precipitation was less than evapotranspiration (precipitation deficit: P15 m downgradient of the drainfield. Although OWTS nitrate inputs caused elevated groundwater nitrate concentrations between the drainfield and the estuary, the majority of nitrate was attenuated via denitrification between the OWTS and 48 m to the estuary. However, DON originating from the OWTS was mobile and contributed to elevated TDN concentrations along the groundwater flowpath to the estuary.

show abstract

Chemical fate and transport in a domestic septic system: Unsaturated and saturated zone geochemistry

Cited by 57 publications

References 33 publications

Investigation of an Onsite Wastewater Treatment System in Sandy Soil: Site Characterization and Fate of Anionic and Nonionic Surfactants

Investigation of an Onsite Wastewater Treatment System in Sandy Soil: Site Characterization and Fate of Anionic and Nonionic Surfactants

Urea Fluctuations in Stream Baseflow across Land Cover Gradients and Seasons in a Coastal Plain River System

Meteorological Influences on Nitrogen Dynamics of a Coastal Onsite Wastewater Treatment System

Contact Info

Product

Resources

About