{"id":85,"date":"2021-06-21T21:51:25","date_gmt":"2021-06-21T21:51:25","guid":{"rendered":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/?post_type=part&p=85"},"modified":"2021-08-06T15:29:33","modified_gmt":"2021-08-06T15:29:33","slug":"potential-for-contamination-from-septic-tank-effluent","status":"publish","type":"part","link":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/part\/potential-for-contamination-from-septic-tank-effluent\/","title":{"raw":"2 Potential for Contamination from Septic Tank Effluent","rendered":"2 Potential for Contamination from Septic Tank Effluent"},"content":{"raw":"
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A compilation of septic tank effluent composition at sites treating domestic wastewater is provided in Table 1. Nitrogen in domestic wastewater occurs primarily as NH<\/em>4<\/em><\/sub>+<\/em><\/sup>-<\/em>N<\/em> (nitrogen present in dissolved ammonium) and septic tank effluent values range from 18-108 mg\/L. Although nitrate is generally absent in the effluent, when NH<\/em>4<\/em><\/sub>+<\/em><\/sup> is nitrified in the unsaturated zone, nitrate concentrations have the potential to exceed the drinking water limit for NO<\/em>3<\/em><\/sub>-<\/em><\/sup>-<\/em>N<\/em> (nitrogen present in dissolved nitrate) of 10 mg\/L. The environmental impacts of groundwater with elevated levels of wastewater-derived nitrate discharging to freshwater lakes and coastal waters are an increasing concern (Persky, 1986; Harris, 1995; Cape Cod Commission, 2015). In addition, effluent phosphorus (P<\/em>) concentrations (3-15 mg\/L, Table 1), are several orders of magnitude higher than guidelines proposed to maintain surface water quality of sensitive lakes and rivers (e.g., 0.01 mg\/L P<\/em> in the USA; USEPA, 2000). Septic system effluent also exceeds drinking water criteria for pathogens and potentially a variety of other trace constituents. Consequently, considering the volume of wastewater generated by septic systems (e.g., 260 L\/d\/capita in the USA, McCray et al., 2005), septic systems may be considered one of the largest potential sources of groundwater contamination, worldwide. However, on-site treatment such as septic systems, provide a variety of treatment steps in the subsurface that have the potential to diminish the contaminant risk. Treatment is particularly active in the unsaturated zone beneath the drainfield. A number of the more important reactions are depicted in Figure 1<\/a> and are discussed in the following sections.<\/p>\r\n

<\/a>Table<\/strong> 1<\/strong> - <\/strong>Septic tank effluent composition at sites treating domestic wastewater, including: electrical conductivity (EC), dissolved organic carbon (DOC), alkalinity (Alk), soluble reactive phosphorus or phosphate (SRP), the artificial sweeteners acesulfame and sucralose, and bacteria and virus colony forming units (CFU).<\/p>\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n
Parameter<\/strong><\/td>\r\nMedian,<\/strong>
<\/strong>Mean (\u00b1 s<\/strong>td <\/strong>d<\/strong>ev<\/strong>),<\/strong>
<\/strong>or Range<\/strong><\/td>\r\n		Reference<\/strong>\r\n(n = number of samples or values)<\/strong><\/td>\r\n<\/tr>\r\n
EC (\u00b5S\/cm)<\/td>\r\n1000<\/td>\r\nRobertson et al., 1991 (n=2)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n2481<\/td>\r\nHarman et al., 1996 (n = 8)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n1456 \u00b1 314<\/td>\r\nRobertson, 2012 (n \u2265 7)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n1480 \u00b1 131<\/td>\r\nGeary and Lucas, 2019 (n = 17)<\/td>\r\n<\/tr>\r\n
DOC (mg\/L)<\/td>\r\n46 \u00b1 27<\/td>\r\nRobertson et al., 1998 (n = 8)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n11 \u00b1 5.0<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n56 \u00b1 26<\/td>\r\nRobertson et al., 2012 (n = 3)<\/td>\r\n<\/tr>\r\n
Alk (mg\/L) as CaCO3<\/sub><\/td>\r\n316 \u00b1 40<\/td>\r\nWilhelm et al., 1996 (n = 6)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n311 \u00b1 102<\/td>\r\nRobertson et al. 1998 (n = 8)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n310 \u00b1 105<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
pH<\/td>\r\n7.1 \u00b1 0.4<\/td>\r\nRobertson et al. 1998 (n = 8)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n7.3 \u00b1 0.2<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n7.4 \u00b1 0.2<\/td>\r\nGeary and Lucas, 2019 (n = 17)<\/td>\r\n<\/tr>\r\n
NH<\/em>4<\/em><\/sub>+<\/em><\/sup>-<\/em>N<\/em> (mg\/L)<\/td>\r\n66 \u00b1 41<\/td>\r\nRobertson et al. 1998 (n = 9)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n4-13<\/td>\r\nUSEPA, 2002<\/td>\r\n<\/tr>\r\n
<\/td>\r\n34 \u00b1 10<\/td>\r\nHinkle et al., 2008 (n = 10)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n18 \u00b1 16<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n58<\/td>\r\nMcCray et al., 2005 (n = 37)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n72 \u00b1 37<\/td>\r\nRobertson et al.,2019 (n = 111)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n108 \u00b1 16<\/td>\r\nGeary and Lucas, 2019 (n = 14)<\/td>\r\n<\/tr>\r\n
NO<\/em>3<\/em><\/sub>-<\/em><\/sup>-<\/em>N<\/em> (mg\/L)<\/td>\r\n0.2 \u00b1 0.3<\/td>\r\nRobertson et al. 1998 (n = 9)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n<1<\/td>\r\nUSEPA, 2002<\/td>\r\n<\/tr>\r\n
<\/td>\r\n0.2<\/td>\r\nMcCray et al., 2005 (n = 33)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n0.03 \u00b1 0.03<\/td>\r\nHinkle et al., 2008 (n = 10)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n4.2 \u00b1 3.2<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n0.2 \u00b1 0.2<\/td>\r\nGeary and Lucas, 2019 (n = 10)<\/td>\r\n<\/tr>\r\n
Total Nitrogen, TKN (mg\/L)<\/td>\r\n26 - 75<\/td>\r\nUSEPA, 2002<\/td>\r\n<\/tr>\r\n
<\/td>\r\n53 \u00b1 14<\/td>\r\nHinkle et al., 2008 (n = 10)<\/td>\r\n<\/tr>\r\n
Total Phosphorus (mg\/L)<\/td>\r\n6 - 12<\/td>\r\nUSEPA, 2002<\/td>\r\n<\/tr>\r\n
<\/td>\r\n4.6 \u00b1 4.2<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
SRP (mg\/L)<\/td>\r\n8.4 \u00b1 3.5<\/td>\r\nRobertson et al. 1998 (n = 9)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n9.0<\/td>\r\nMcCray et al., 2005 (n = 35)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n3.2 \u00b1 2.6<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n8.2 \u00b1 4.9<\/td>\r\nRobertson et al.,2019 (n = 123)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n15 \u00b1 1.8<\/td>\r\nGeary and Lucas, 2019 (n = 16)<\/td>\r\n<\/tr>\r\n
Cl<\/em>-<\/em><\/sup> (mg\/L)<\/td>\r\n67 \u00b1 64<\/td>\r\nRobertson et al. 1998 (n = 9)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n32 \u00b1 16<\/td>\r\nHinkle et al., 2008 (n = 10)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n54 \u00b1 16<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n64<\/td>\r\nRobertson et al.,2019 (n = 106)<\/td>\r\n<\/tr>\r\n
Na<\/em>+<\/em><\/sup> (mg\/L)<\/td>\r\n54 \u00b1 27<\/td>\r\nRobertson et al. 1998 (n = 9)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n49 \u00b1 29<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
K<\/em>+<\/em><\/sup> (mg\/L)<\/td>\r\n22 \u00b1 15<\/td>\r\nRobertson et al. 1998 (n = 9)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n26 \u00b1 8<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
Ca<\/em>2<\/em><\/sup>+<\/em><\/sup> (mg\/L)<\/td>\r\n38 \u00b1 36<\/td>\r\nRobertson et al. 1998 (n = 9)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n96 \u00b1 22<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
B<\/em> (mg\/L)<\/td>\r\n0.51 \u00b1 0.05<\/td>\r\nLeBlanc, 1984 (n = 3)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n0.11 \u00b1 0.03<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n0.28 \u00b1 0.02<\/td>\r\nBassett et al., 1995 (n = 3)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n0.49<\/td>\r\nVengosh et al., 1994 (n = 21)<\/td>\r\n<\/tr>\r\n
Fe<\/em> (mg\/L)<\/td>\r\n0.45 \u00b1 0.41<\/td>\r\nRobertson et al. 1998 (n = 8)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n0.12 \u00b1 0.06<\/td>\r\nWithers et al., 2011 (n = 37)<\/td>\r\n<\/tr>\r\n
Al<\/em> (mg\/L)<\/td>\r\n0.1 \u00b1 0.1<\/td>\r\nRobertson et al. 1998 (n = 6)<\/td>\r\n<\/tr>\r\n
Acesulfame (\u00b5g\/L)<\/td>\r\n57<\/td>\r\nSnider et al., 2017 (single family, n = 14)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n32<\/td>\r\nSnider et al., 2017 (communal, n = 36)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n44 \u00b1 32<\/td>\r\nRobertson et al., 2019 (n = 56)<\/td>\r\n<\/tr>\r\n
Sucralose (\u00b5g\/L)<\/td>\r\n40 \u00b1 25<\/td>\r\nOppenheimer et al., 2011 (n = 8)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n51<\/td>\r\nSnider et al., 2017 (single family, n = 14)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n28<\/td>\r\nSnider et al., 2017 (communal, n = 36)<\/td>\r\n<\/tr>\r\n
<\/td>\r\n40 \u00b1 34<\/td>\r\nRobertson et al., 2019 (n = 56)<\/td>\r\n<\/tr>\r\n
Fecal Bacteria (CFU\/100 mL)<\/td>\r\n105<\/sup><\/td>\r\nViraraghavan, 1978<\/td>\r\n<\/tr>\r\n
<\/td>\r\n106<\/sup><\/td>\r\nShadford et al., 1997<\/td>\r\n<\/tr>\r\n
<\/td>\r\n106<\/sup>\u00ad<\/sub> - 108<\/sup><\/td>\r\nUSEPA, 2002<\/td>\r\n<\/tr>\r\n
<\/td>\r\n105<\/sup><\/td>\r\nGeary and Lucas, 2019<\/td>\r\n<\/tr>\r\n
Coliphage Virus (CFU\/100mL)<\/td>\r\n108<\/sup><\/td>\r\nDeborde et al., 1998a<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>","rendered":"
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A compilation of septic tank effluent composition at sites treating domestic wastewater is provided in Table 1. Nitrogen in domestic wastewater occurs primarily as NH<\/em>4<\/em><\/sub>+<\/em><\/sup>–<\/em>N<\/em> (nitrogen present in dissolved ammonium) and septic tank effluent values range from 18-108 mg\/L. Although nitrate is generally absent in the effluent, when NH<\/em>4<\/em><\/sub>+<\/em><\/sup> is nitrified in the unsaturated zone, nitrate concentrations have the potential to exceed the drinking water limit for NO<\/em>3<\/em><\/sub>–<\/em><\/sup>–<\/em>N<\/em> (nitrogen present in dissolved nitrate) of 10 mg\/L. The environmental impacts of groundwater with elevated levels of wastewater-derived nitrate discharging to freshwater lakes and coastal waters are an increasing concern (Persky, 1986; Harris, 1995; Cape Cod Commission, 2015). In addition, effluent phosphorus (P<\/em>) concentrations (3-15 mg\/L, Table 1), are several orders of magnitude higher than guidelines proposed to maintain surface water quality of sensitive lakes and rivers (e.g., 0.01 mg\/L P<\/em> in the USA; USEPA, 2000). Septic system effluent also exceeds drinking water criteria for pathogens and potentially a variety of other trace constituents. Consequently, considering the volume of wastewater generated by septic systems (e.g., 260 L\/d\/capita in the USA, McCray et al., 2005), septic systems may be considered one of the largest potential sources of groundwater contamination, worldwide. However, on-site treatment such as septic systems, provide a variety of treatment steps in the subsurface that have the potential to diminish the contaminant risk. Treatment is particularly active in the unsaturated zone beneath the drainfield. A number of the more important reactions are depicted in Figure 1<\/a> and are discussed in the following sections.<\/p>\n

<\/a>Table<\/strong> 1<\/strong> – <\/strong>Septic tank effluent composition at sites treating domestic wastewater, including: electrical conductivity (EC), dissolved organic carbon (DOC), alkalinity (Alk), soluble reactive phosphorus or phosphate (SRP), the artificial sweeteners acesulfame and sucralose, and bacteria and virus colony forming units (CFU).<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Parameter<\/strong><\/td>\nMedian,<\/strong>
<\/strong>Mean (\u00b1 s<\/strong>td <\/strong>d<\/strong>ev<\/strong>),<\/strong>
<\/strong>or Range<\/strong><\/td>\n		Reference<\/strong>
\n(n = number of samples or values)<\/strong><\/td>\n<\/tr>\n
EC (\u00b5S\/cm)<\/td>\n1000<\/td>\nRobertson et al., 1991 (n=2)<\/td>\n<\/tr>\n
<\/td>\n2481<\/td>\nHarman et al., 1996 (n = 8)<\/td>\n<\/tr>\n
<\/td>\n1456 \u00b1 314<\/td>\nRobertson, 2012 (n \u2265 7)<\/td>\n<\/tr>\n
<\/td>\n1480 \u00b1 131<\/td>\nGeary and Lucas, 2019 (n = 17)<\/td>\n<\/tr>\n
DOC (mg\/L)<\/td>\n46 \u00b1 27<\/td>\nRobertson et al., 1998 (n = 8)<\/td>\n<\/tr>\n
<\/td>\n11 \u00b1 5.0<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
<\/td>\n56 \u00b1 26<\/td>\nRobertson et al., 2012 (n = 3)<\/td>\n<\/tr>\n
Alk (mg\/L) as CaCO3<\/sub><\/td>\n316 \u00b1 40<\/td>\nWilhelm et al., 1996 (n = 6)<\/td>\n<\/tr>\n
<\/td>\n311 \u00b1 102<\/td>\nRobertson et al. 1998 (n = 8)<\/td>\n<\/tr>\n
<\/td>\n310 \u00b1 105<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
pH<\/td>\n7.1 \u00b1 0.4<\/td>\nRobertson et al. 1998 (n = 8)<\/td>\n<\/tr>\n
<\/td>\n7.3 \u00b1 0.2<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
<\/td>\n7.4 \u00b1 0.2<\/td>\nGeary and Lucas, 2019 (n = 17)<\/td>\n<\/tr>\n
NH<\/em>4<\/em><\/sub>+<\/em><\/sup>–<\/em>N<\/em> (mg\/L)<\/td>\n66 \u00b1 41<\/td>\nRobertson et al. 1998 (n = 9)<\/td>\n<\/tr>\n
<\/td>\n4-13<\/td>\nUSEPA, 2002<\/td>\n<\/tr>\n
<\/td>\n34 \u00b1 10<\/td>\nHinkle et al., 2008 (n = 10)<\/td>\n<\/tr>\n
<\/td>\n18 \u00b1 16<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
<\/td>\n58<\/td>\nMcCray et al., 2005 (n = 37)<\/td>\n<\/tr>\n
<\/td>\n72 \u00b1 37<\/td>\nRobertson et al.,2019 (n = 111)<\/td>\n<\/tr>\n
<\/td>\n108 \u00b1 16<\/td>\nGeary and Lucas, 2019 (n = 14)<\/td>\n<\/tr>\n
NO<\/em>3<\/em><\/sub>–<\/em><\/sup>–<\/em>N<\/em> (mg\/L)<\/td>\n0.2 \u00b1 0.3<\/td>\nRobertson et al. 1998 (n = 9)<\/td>\n<\/tr>\n
<\/td>\n<1<\/td>\nUSEPA, 2002<\/td>\n<\/tr>\n
<\/td>\n0.2<\/td>\nMcCray et al., 2005 (n = 33)<\/td>\n<\/tr>\n
<\/td>\n0.03 \u00b1 0.03<\/td>\nHinkle et al., 2008 (n = 10)<\/td>\n<\/tr>\n
<\/td>\n4.2 \u00b1 3.2<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
<\/td>\n0.2 \u00b1 0.2<\/td>\nGeary and Lucas, 2019 (n = 10)<\/td>\n<\/tr>\n
Total Nitrogen, TKN (mg\/L)<\/td>\n26 – 75<\/td>\nUSEPA, 2002<\/td>\n<\/tr>\n
<\/td>\n53 \u00b1 14<\/td>\nHinkle et al., 2008 (n = 10)<\/td>\n<\/tr>\n
Total Phosphorus (mg\/L)<\/td>\n6 – 12<\/td>\nUSEPA, 2002<\/td>\n<\/tr>\n
<\/td>\n4.6 \u00b1 4.2<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
SRP (mg\/L)<\/td>\n8.4 \u00b1 3.5<\/td>\nRobertson et al. 1998 (n = 9)<\/td>\n<\/tr>\n
<\/td>\n9.0<\/td>\nMcCray et al., 2005 (n = 35)<\/td>\n<\/tr>\n
<\/td>\n3.2 \u00b1 2.6<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
<\/td>\n8.2 \u00b1 4.9<\/td>\nRobertson et al.,2019 (n = 123)<\/td>\n<\/tr>\n
<\/td>\n15 \u00b1 1.8<\/td>\nGeary and Lucas, 2019 (n = 16)<\/td>\n<\/tr>\n
Cl<\/em>–<\/em><\/sup> (mg\/L)<\/td>\n67 \u00b1 64<\/td>\nRobertson et al. 1998 (n = 9)<\/td>\n<\/tr>\n
<\/td>\n32 \u00b1 16<\/td>\nHinkle et al., 2008 (n = 10)<\/td>\n<\/tr>\n
<\/td>\n54 \u00b1 16<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
<\/td>\n64<\/td>\nRobertson et al.,2019 (n = 106)<\/td>\n<\/tr>\n
Na<\/em>+<\/em><\/sup> (mg\/L)<\/td>\n54 \u00b1 27<\/td>\nRobertson et al. 1998 (n = 9)<\/td>\n<\/tr>\n
<\/td>\n49 \u00b1 29<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
K<\/em>+<\/em><\/sup> (mg\/L)<\/td>\n22 \u00b1 15<\/td>\nRobertson et al. 1998 (n = 9)<\/td>\n<\/tr>\n
<\/td>\n26 \u00b1 8<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
Ca<\/em>2<\/em><\/sup>+<\/em><\/sup> (mg\/L)<\/td>\n38 \u00b1 36<\/td>\nRobertson et al. 1998 (n = 9)<\/td>\n<\/tr>\n
<\/td>\n96 \u00b1 22<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
B<\/em> (mg\/L)<\/td>\n0.51 \u00b1 0.05<\/td>\nLeBlanc, 1984 (n = 3)<\/td>\n<\/tr>\n
<\/td>\n0.11 \u00b1 0.03<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
<\/td>\n0.28 \u00b1 0.02<\/td>\nBassett et al., 1995 (n = 3)<\/td>\n<\/tr>\n
<\/td>\n0.49<\/td>\nVengosh et al., 1994 (n = 21)<\/td>\n<\/tr>\n
Fe<\/em> (mg\/L)<\/td>\n0.45 \u00b1 0.41<\/td>\nRobertson et al. 1998 (n = 8)<\/td>\n<\/tr>\n
<\/td>\n0.12 \u00b1 0.06<\/td>\nWithers et al., 2011 (n = 37)<\/td>\n<\/tr>\n
Al<\/em> (mg\/L)<\/td>\n0.1 \u00b1 0.1<\/td>\nRobertson et al. 1998 (n = 6)<\/td>\n<\/tr>\n
Acesulfame (\u00b5g\/L)<\/td>\n57<\/td>\nSnider et al., 2017 (single family, n = 14)<\/td>\n<\/tr>\n
<\/td>\n32<\/td>\nSnider et al., 2017 (communal, n = 36)<\/td>\n<\/tr>\n
<\/td>\n44 \u00b1 32<\/td>\nRobertson et al., 2019 (n = 56)<\/td>\n<\/tr>\n
Sucralose (\u00b5g\/L)<\/td>\n40 \u00b1 25<\/td>\nOppenheimer et al., 2011 (n = 8)<\/td>\n<\/tr>\n
<\/td>\n51<\/td>\nSnider et al., 2017 (single family, n = 14)<\/td>\n<\/tr>\n
<\/td>\n28<\/td>\nSnider et al., 2017 (communal, n = 36)<\/td>\n<\/tr>\n
<\/td>\n40 \u00b1 34<\/td>\nRobertson et al., 2019 (n = 56)<\/td>\n<\/tr>\n
Fecal Bacteria (CFU\/100 mL)<\/td>\n105<\/sup><\/td>\nViraraghavan, 1978<\/td>\n<\/tr>\n
<\/td>\n106<\/sup><\/td>\nShadford et al., 1997<\/td>\n<\/tr>\n
<\/td>\n106<\/sup>\u00ad<\/sub> – 108<\/sup><\/td>\nUSEPA, 2002<\/td>\n<\/tr>\n
<\/td>\n105<\/sup><\/td>\nGeary and Lucas, 2019<\/td>\n<\/tr>\n
Coliphage Virus (CFU\/100mL)<\/td>\n108<\/sup><\/td>\nDeborde et al., 1998a<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n","protected":false},"parent":0,"menu_order":2,"template":"","meta":{"pb_part_invisible":false,"pb_part_invisible_string":""},"contributor":[],"license":[],"class_list":["post-85","part","type-part","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/wp-json\/pressbooks\/v2\/parts\/85","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/wp-json\/pressbooks\/v2\/parts"}],"about":[{"href":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/wp-json\/wp\/v2\/types\/part"}],"version-history":[{"count":10,"href":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/wp-json\/pressbooks\/v2\/parts\/85\/revisions"}],"predecessor-version":[{"id":267,"href":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/wp-json\/pressbooks\/v2\/parts\/85\/revisions\/267"}],"wp:attachment":[{"href":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/wp-json\/wp\/v2\/media?parent=85"}],"wp:term":[{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/wp-json\/wp\/v2\/contributor?post=85"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/books.gw-project.org\/septic-system-impacts-on-groundwater-quality\/wp-json\/wp\/v2\/license?post=85"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}