Water Quality in the Coos Estuary: Other Pollutants
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Previously problematic point sources of pollution may still pose threats to water quality.
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Outside of some known “pollution pockets” in the Coos estuary, it appears that concentrations of dissolved pollutants generally meet USEPA standards.
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Many streams in the study area are listed under Section 303d of the Clean Water Act for insufficient information.
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More comprehensive monitoring is needed to fully assess the status of other pollutants in the Coos estuary.
Summary:
Total Organic Carbon
Total organic carbon (TOC) is an indicator of the presence and abundance of organic compounds in the environment and is found naturally in estuary waters and sediments. High TOC levels are often associated with the presence of other pollutants, including the toxic by-products of organic decomposition (ammonia and sulfide)(Hyland et al. 2005). Additionally, dissolved organic matter binds with metals such as mercury (Swett 2010) and other pollutants, including pesticides and herbicides (Wijayaratne and Means 1984), as well as polychlorinated biphenyls (PCBs)(Brownawell and Farrington 1986). Consequently, TOC (more specifically the dissolved organic carbon (DOC) component of TOC – see below) may facilitate pollutant transport between sediments and the water column (Swett 2010). TOC may also result in harmful byproducts (i.e., trihalomethanes) during the water treatment process (Fleck et al. 2007). The presence and abundance of TOC is often used as an indirect measure of water quality and sediment contamination.
The Oregon Department of Environmental Quality (ODEQ) has monitored total organic carbon (TOC) in the South Slough, Isthmus Slough, and Coos River subsystems (Figure 1)(ODEQ 2001, 2007a, 2007b, 2009a, 2009b). TOC sampling is sporadic, with the most recent data coming from 2009 (Table 1). The highest TOC levels were recorded in the South Slough subsystem near the Joe Ney Landfill (closed in 2013 and most recently used exclusively for construction debris)(see sidebar).
The Coos Bay/North Bend Water board monitored TOC from 2010-2012 in the Pony Slough (Pony Creek and Merritt Lake) and Lower Bay (North Spit) Subsystems as part of their drinking water program (Water Board 2012). TOC levels in Pony Slough and the Lower Bay were 3-4 mg/L on average over these years (Table 2). These levels are similar to the mean observed concentrations at ODEQ sites at South Slough, Isthmus Slough, and Coos River.
The Joe Ney Construction and Demolition Landfill is located near Crown Point in the South Slough Subsystem (Figure 1). The facility is owned and was operated by Coos County from 1981 to 2013. Past landfill practices have likely contributed to groundwater contamination. For example, a complaint was filed in 1986 by a man who allegedly saw a “truck dumping 55-gallon drums” into the Joy Ney dump “which were immediately covered.”
The Oregon Department of Environmental Quality (ODEQ) monitors groundwater at the site with semi-annual sampling/analyses using a network of 18 monitoring wells, and 4 residential wells. Surface water is also monitored on a semi-annual basis with samples collected from 5 locations. These monitoring points were established between 1989 through 1999 during the course of several environmental investigations conducted at this site.
Based on groundwater monitoring results, landfill activities have affected groundwater, and for that reason, Coos County has prepared a remedial investigation work plan for this site which led to the County’s closure of the dump.
Source: ODEQ 2014b
Dissolved Organic Carbon
Dissolved organic carbon (DOC) is a component of TOC, the measurement of which allows for particularly accurate TOC assessments in the water column. Unfortunately, little is known about the level of DOC in the Coos estuary.
What we do know comes from Pregnall (1983) who studied primary production in South Slough to help quantify DOC produced by Coos estuary biota. His findings suggest that photosynthesis of South Slough intertidal algae (Enteromorpha prolifera) releases 0.13-0.57 mg of DOC per gram of dry weight biomass per hour. This rate was shown to increase in response to changes commonly associated with estuarine environments such as daily salinity fluctuations.
More research is needed to fully understand estuarine DOC dynamics in the Coos estuary and how measuring DOC concentrations can be used to improve water quality assessments.
Bauer and Bianchi (2011) explain that estuaries are complex systems involving the exchange of carbon between terrestrial, marine, and atmospheric sources. They point out that the complexity of biogeochemical processes in estuaries is compounded by temporal variability. For example, estuarine biogeochemical processes respond to twice daily tidal flooding, daily or weekly storm events, seasonal or monthly changes in temperature and precipitation, and multi-year to decades-long changes in long term climatic regimes (e.g., El Niño Southern Oscillation and Pacific Decadal Oscillation). In addition to these natural processes, estuarine carbon cycling is carried out against a backdrop of human land use activities, which can further complicate an already intricate process (Bauer and Bianchi 2011). Consequently, we have a limited understanding of the role of DOC in governing the flux of organic matter and trace metals in coastal and estuarine systems (Martin et al. 1995).
Metals can readily dissolve in water, and can find their way into estuarine waters from various sources including manufacturing, mining and farming activities (the latter featuring land-applied herbicides and pesticides), and air pollution from fossil fuel combustion (USEPA 2007a). Many metals (e.g., iron, copper ) are also naturally abundant elements found in coastal watersheds (Shacklette and Boerngen 1984; USEPA 2007b). Table 3 summarizes the dissolved metals discussed below.
Water quality criteria for dissolved metals have been developed for both aquatic life and human health (ODEQ 2014a; USEPA 1993, 2007a, 2007b, 2009). For aquatic life criteria, dissolved metal standards are evaluated using an acute criterion (CMC) and a chronic criterion (CCC)(see sidebar). For human health, standards are classified into categories for the safe consumption of 1) water and aquatic organisms, and 2) aquatic organisms only. Figure 2 summarizes the organizational structure of dissolved metal standards for each pollutant.
Data describing dissolved metal concentrations are available in the Pony Slough, Sough Slough, Coos River, and Isthmus Slough subsystems (Figure 3 and Table 4)(ODEQ 1995, 1998a, 2002, 2006a, 2006b, 2006c, 2007a, 2007b, 2009a, 2009b; Water Board 2012).
From 1998 to 2012, 13 sites in the study area (including the subsystems listed above)(Figure 4 and Table 3) were listed under the Clean Water Act for insufficient data or as sites of “potential concern”. These listings reinforce the fact that we don’t yet have enough information to form a comprehensive understanding of the status of dissolved metals in the Coos estuary.
Of the 13 sites mentioned, only three were listed as potential water quality threats to both aquatic life and human health due to
elevated concentrations of dissolved metals (Coos Bay in 1998 and Day and Storey Creeks in 2004). The remaining 10 sites were listed due to informational gaps (Table 3)(ODEQ 1998b, 2004, 2012).
The status of specific dissolved metals in the Coos estuary and surrounding area is detailed below. This inventory presents USEPA standards for both aquatic life and human health. However, the toxic effects of exposure focus on human health, because the effects on aquatic life can vary significantly by species and environmental conditions (e.g., pH, organic content, sediment characteristics, conductivity, etc.)(USEPA 1980; USEPA 2007b).
Aluminum
Dissolved aluminum (1995-2009) concentrations appear to be higher in Isthmus Slough than in South Slough or Pony Slough.
Aluminum is a non-priority pollutant for aquatic life standards (see sidebar)(USEPA 1993).
Antimony
Antimony concentrations (2005-2009) in South Slough at the former Joe Ney Landfill Disposal Site (JNDS) meet USEPA standards for human consumption of both water and aquatic organisms (Table 4).
In 2004, Day Creek (South Slough), Mettman Creek (Upper Bay), as well as Morgan Creek and the West Fork of the Millicoma River (Coos River) were all listed due to insufficient information (Table 3)(ODEQ 2004).
Antimony is a priority pollutant, meaning that it is a toxic pollutant with established chemical standards that is frequently found in water (USEPA 1993, 2014). Human exposure to antimony can affect the cardiovascular (heart and blood vessels) and respiratory (breathing) systems, but is not known to have any cancer effects (CDC 2014).
Arsenic
At South Slough’s JNDS, arsenic concentrations (1995-2009) may be harmful to saltwater aquatic life. Elevated arsenic concentrations at South Slough’s JNDS may not meet USEPA recommended concentrations for the safe human consumption of both water and aquatic organisms. In 2012, arsenic concentrations in the Pony Slough subsystem at Merritt Lake met USEPA guidelines (Table 4).
In 2004, arsenic was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
Arsenic is a priority pollutant for both aquatic life and human health (USEPA 1993). Human exposure to arsenic can affect the dermal (skin), gastrointestinal (digestive), hepatic (liver), neurological (nervous system), and respiratory (breathing) systems. It is a known carcinogen (CDC 2014).
Barium
In 2004, barium was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
The data that are available suggest that average barium concentrations (1995-2009) at South Slough’s JNDS appear to meet the USEPA standards for safe human consumption of water and aquatic organisms, but maximum observed concentrations do not meet these standards (Table 4).
Barium is a non-priority pollutant (USEPA 1993). However, human exposure to barium may affect the cardiovascular (heart and blood vessels), gastrointestinal (digestive), and reproductive (producing children) systems. It does not have any cancer effects (CDC 2014).
Beryllium
In 2004, beryllium was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
However, the data that are available suggest that dissolved beryllium concentrations (1995-2009) in South Slough’s JNDS meet USEPA standards for both aquatic life and human health (Table 4).
Beryllium is a priority pollutant for human health (USEPA 1993). Human exposure to beryllium may affect the gastrointestinal (digestive), immunological (immune system), and respiratory (breathing) systems. It is a known carcinogen (CDC 2014).
Boron
Average boron concentrations (1995-2009) are higher in Isthmus Slough than in either Sough Slough JNDS or Pony Slough at Merritt Lake. However, the highest maximum observed concentration occurred in South Slough at JNDS (Table 4).
The USEPA has not established water quality guidelines for boron.
Cadmium
In 2004, cadmium was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
The available data suggest that cadmium concentrations in the study are low. From 1995-2009, ODEQ made 38 cadmium observations at South Slough’s JNDS. All of these observations were below detectable limits, indicating that cadmium concentrations at JNDS likely meet USEPA standards for human health. USEPA standards for freshwater aquatic life, however, are much closer to detectable limits. Therefore, it’s difficult to know if the JNDS cadmium concentrations meet the freshwater aquatic life standard for indefinite exposure (Table 4).
Cadmium is a priority pollutant (USEPA 1993). Human exposure to cadmium may affect the cardiovascular (heart and blood vessels), gastrointestinal (digestive), neurological (nervous system), renal (urinary and kidneys), reproductive (producing children), and respiratory (breathing) systems. It is a known carcinogen (CDC 2014).
Chromium
Chromium concentrations (1995-2009) in South Slough’s JNDS meet USEPA standards for both aquatic life and human health (Table 4).
In 1998, chromium was listed as a potential concern for aquatic life in Coos Bay (Upper Bay)(ODEQ 1998b). In 2004, it was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and
Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
Chromium is a priority pollutant (USEPA 1993). Human exposure to chromium may affect the immunological (immune system), renal (urinary and kidneys), and respiratory systems. It is a known carcinogen (CDC 2014).
The USEPA has developed a list of 126 priority pollutants. Priority status is assessed based on the following criteria:
1.) Must be included on USEPA’s list of toxic pollutants
2.) Must have chemical standards and published testing methods
3.) Must be frequently found in water
4.) Must have been produced domestically in substantial quantities
Source: USEPA 2014
Cobalt
About half of the cobalt observations (1995-2009) at South Slough’s JNDS are below detectable limits, indicating that the accuracy of monitoring efforts could be improved by more complete information (Table 4). USEPA has not established water quality guidelines for cobalt (USEPA 1993).
Copper
Copper concentrations at South Slough’s JDNS (1995-2009) as well as Pony Slough at Merritt Lake (2012) appear to meet the USEPA standard for safe human consumption. However, brief exposure to these sites may be harmful to saltwater aquatic life (Table 4).
In 1998, copper was listed as a potential concern for aquatic life in Coos Bay (Upper Bay)(ODEQ 1998b). In 2004, it was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
Copper is a priority pollutant (USEPA 1993). Human exposure to copper may affect the gastrointestinal (digestive), hematological (blood forming), and hepatic (liver) systems. It does not have any cancer effects (CDC 2014).
Iron
Iron concentrations in the Coos River subsystem (2009) as well as in Isthmus Slough (2006-2007) and South Slough’s JNDS (1995-2009) may be harmful to freshwater aquatic life (Table 4).
In 2004, iron was listed as a potential concern for both aquatic life and human health at Day and Storey Creeks (South Slough). In 2012, it was listed for insufficient information at Mettman Creek (Upper Bay) as well as the following waters in the Coos River subsystem: Daniels Creek, East Fork Millicoma, West Fork Millicoma, Morgan Creek, and South Fork Coos (Table 3)(ODEQ 2004). Iron is a non-priority pollutant.
Lead
Lead observations at Pony Slough Merritt Lake (2012) and South Slough’s JNDS (1995-2009) seem to meet USEPA standards for aquatic life (Table 4).
In 1998, lead was listed as a potential concern for aquatic life in Coos Bay (Upper Bay)(ODEQ 1998b). In 2004, it was listed for insufficient information in Day Creek (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
Lead is a priority pollutant for aquatic life (USEPA 1993). Although it is not listed as a priority pollutant for human health, lead exposure is associated with harmful health affects to the cardiovascular (heart and blood vessels), gastrointestinal (digestive), hematological (blood forming), musculoskeletal (muscles and skeleton), neurological (nervous system), ocular (eyes), renal (urinary and kidneys), and reproductive (producing children) systems. It is reasonably anticipated to be a carcinogen (CDC 2014)
Lanthanum
Only sixteen percent of lanthanum observations at South Slough’s JNDS (1995-2009) are above detectable limits, indicating that accuracy of cobalt monitoring efforts could be improved by more complete information (Table 4). USEPA has not established water quality guidelines for lanthanum.
Lithium
Lithium concentrations appear to be an order of magnitude higher in Isthmus Slough (2006-2007) than at South Slough’s JNDS (1995-2009) or in the Coos River (2009) subsystem (Table 4). USEPA has not established water quality guidelines for lithium.
Magnesium
Magnesium concentrations are much higher in Isthmus Slough (2006-2007) than at South Slough’s JNDS (1995-2009) or in the Coos River (2009) subsystem (Table 4). USEPA has not established water quality guidelines for magnesium.
Manganese
In 2004, Manganese was listed as a potential concern for human health in both Day and Storey Creek (South Slough). It was also listed for insufficient information at Mettman Creek (Upper Bay) as well as Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004). In 2012, Coalbank, Davis, Isthmus, and Shinglehouse Sloughs (Isthmus Slough subsystem) were all listed as informational gaps (Table 3)(ODEQ 2012).
The available data suggest that manganese concentrations may not meet USEPA standards. The estimated average manganese concentration does not meet the USEPA guideline for safe human consumption of either water or aquatic organisms in Isthmus slough (2006-2007); nor does it meet these standards at South Slough’s JNDS (1995-2009). In the Coos River subsystem (2009), maximum observed concentrations do not meet USEPA standards for safe human consumption (Table 4).
Manganese is a non-priority pollutant (USEPA 1993). However, human exposure to manganese may affect the cardiovascular (heart and blood vessels), hepatic (liver), neurological (nervous system) and respiratory (breathing) systems. It does not have any cancer effects (CDC 2014).
Mercury
Indefinite exposure to mercury concentrations at South Slough’s JNDS (1995-2009) may be harmful to both freshwater and saltwater aquatic life. However, mercury concentrations appear to meet the USEPA recommended standard for safe human consumption of water (Table 4). For a discussion of mercury in fish tissues, see Chapter 10: Sediments in the Coos Estuary and Lower Coos Watershed.
In 2004, mercury was listed for insufficient information at Day Creek (South Slough)(Table 3)(ODEQ 2004).
Mercury is a priority pollutant for both aquatic life and human health (USEPA 1993). Human exposure to mercury may affect the gastrointestinal (digestive), neurological (nervous system), ocular (eyes), and renal (urinary and kidneys) systems. It does not have any cancer effects (CDC 2014).
Molybdenum
Only 21% of molybdenum observations at South Slough’s JNDS (1995-2009) were above detectable limits, indicating that the accuracy of monitoring efforts could be improved by more complete information (Table 4). USEPA has not established water quality guidelines for molybdenum.
Nickel
Dissolved nickel concentrations at South Slough’s JNDS (1995-2009) easily meet USEPA standards for safe human consumption of both water and aquatic organisms (Table 4).
In 2004, nickel was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
Nickel is a priority pollutant for both aquatic life and human health (USEPA 1993). Human exposure to nickel may affect the cardiovascular (heart and blood vessels), dermal (skin), immunological (immune system), and respiratory (breathing) systems. It is a known carcinogen (CDC 2014).
Selenium
In 2004, selenium was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
However, the available data suggest that selenium concentrations at South Slough’s JNDS (1995-2009) meet USEPA standards for both aquatic life and human health.
Selenium is a priority pollutant for both aquatic life and human health (USEPA 1993). Human exposure to selenium may affect the dermal (skin), and reproductive (producing children) systems. It is reasonably anticipated to be a carcinogen (CDC 2014).
Silver
Indefinite exposure to dissolved silver at South Slough’s JNDS (1995-2009) may be harmful to freshwater aquatic life (Table 4).
In 2004, silver was listed for insufficient information in Storey and Day Creeks (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
Silver is a priority pollutant for aquatic life (USEPA 1993). Although it is not listed as a priority pollutant for human health, exposure to silver is associated with harmful health effects to the renal (urinary and kidneys) and reproductive (producing children) systems. It does not have any cancer effects (CDC 2014).
Thallium
All twenty thallium observation at South Slough’s JNDS (1995-2009) are below detectable limits. However, the estimated average concentration indicates that thallium concentrations at JNDS may not meet USEPA standards for safe human consumption of either water or aquatic life (Table 4).
In 2004, thallium was listed for insufficient information in Day Creek (South Slough), Mettman Creek (Upper Bay), and Morgan Creek and the West Fork of the Millicoma River (Coos River)(Table 3)(ODEQ 2004).
Thallium is a priority pollutant for human health (USEPA 1993). Human exposure to thallium may affect the gastrointestinal (digestive), hepatic (liver), neurological (nervous system), and renal (urinary or kidneys) systems. It does not have any cancer effects (CDC 2014).
Vanadium
Only 8% of all vanadium observations at South Slough’s JNDS (1995-2009) are above detectable limits, indicating that the accuracy of monitoring efforts could be improved by more complete information.
USEPA has not established water quality guidelines for vanadium. Human exposure to vanadium may affect the cardiovascular (heart and blood vessels), gastrointestinal (digestive), renal (urinary and kidneys), reproductive (producing children), and respiratory (breathing) systems. It does not have any cancer effects (CDC 2014).
Zinc
Dissolved zinc concentrations at South Slough’s JNDS (1995-2009) easily meet USEPA standards for both aquatic life and human health (Table 4).
Zinc is a priority pollutant for both aquatic life and human health (USEPA 1993). Human exposure to zinc may affect the gastrointestinal (digestive), hematological (blood forming), and respiratory (breathing) systems. It does not have any cancer effects (CDC 2014).
The Stockholm Convention on Persistent Organic Pollutants is a multinational agreement intended to eliminate or mitigate the production/use of harmful Persistent organic pollutants (POPs).POPs are “organic” (i.e., carbon-based) pollutants with high potential for environmental damage.
In 2001, the Convention identified 12 priority POPs, and an additional nine POPs were added in 2009.
These POPs were selected based on the following properties:
Persistence: The ability to remain intact in the environment for many years
Long-range distribution: Widely distributed throughout the environment as a result of natural processes
Bioaccumulation and Biomagnification: Accumulation in fatty tissues of living organisms, with higher concentrations occurring at higher levels in the food chain
Toxicity: Associated with harmful health affects in humans and wildlife
Long-range transport of POPs is often facilitated by the migration of animals that have been exposed to them. Due to the characteristics of POPs, predatory animals that are high up the food chain, such as fish, raptors, mammals, and humans, are at elevated risk for absorbing high POP concentrations.
Source: Stockholm Convention 2008
“Persistent organic pollutants” (POPs) are widely distributed herbicides, pesticides, insecticides, and other biocides that are internationally recognized for their potential to cause environmental damage (see “Stockholm Convention” sidebar). In addition to POPs, tributyltin (TBT), an anti-fouling chemical found in boat bottom paints, has historically been a concern in the Coos estuary (Wolniakowski et al. 1987). Table 5 details the properties of the most common POPs and provides their associated water quality standards.
Although little is known about dissolved POPs and TBT in the Coos estuary, what we do know comes from the Coos Bay/North Bend Water Board, which monitors Merritt Lake (Pony Slough Subsystem) for eight POPs including aldrin and dieldrin, chordane, DDT, endrin, heptachlor, HCB, PCBs, and toxaphene. Since the monitoring program began in 1985, the Water Board has not recorded any POPs observations above detectable limits (Water Board 2012).
Cornu et al. (2012) note that a wide range of pesticides, including POPs such as DDT, have been detected by ODEQ in low (“unquantifiable”) amounts at 29 sites in the Coos Basin. Although the location of many these sites is undisclosed, it is clear that sampling occurred at no fewer than three Sough Slough locations, including Joe Ney Slough, Collver Point, and Brown’s Cove (ODEQ 2014b).
For additional information about POPs, TBT, biocides, and other contaminants, refer to Chapter 10: Sediment Contamination in the Coos Estuary.