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Like most states, Texas has no comprehensive fish-monitoring program. While there are presently over 1,760
fixed monitoring stations on Texas rivers and reservoirs that provide data to the state, currently only 13 are conducting regular fish tissue monitoring.* In addition, the state does test fish tissue for contaminants when a report of a chemical spill or some other information leads state health officials to believe human health may be threatened. Testing fish is expensive; a detailed tissue sampling of one fish might cost $500, and a full scan, which examines the liver and reproductive organs to pinpoint sources of dangerous contaminants, might exceed $2,275 per sample.*
During the most recent statewide water quality report, the TCEQ reported that it was only able to assess the
"fish consumption" use of river and stream miles in 395 river and stream miles, or about two percent of all stream miles surveyed, and these 395 miles were based upon existing fish
consumption advisories and closures issued by the Texas Department of Health, not upon new data. In fact, during the most recent reporting period, only 192 miles were assessed for fish tissue
concerns, with fish tissue from only one area -- the Black Cypress Bayou -- with concerns due to high levels of mercury.* In addition to this very limited testing, TCEQ has been participating in an EPA four-year national study of chemical residues in lake fish which has increased testing of fish for certain highly toxic compounds. For example, samples of bottom-dwelling common carp, from Lake Palestine, had the highest levels of arsenic found nationwide, while blue catfish from B.A. Steinhagen Lake had the highest concentrations of dioxins and furans.*
The limited information gathered by TCEQ concerning elevated levels of toxic concentrations in fish tissue is
shared with the Texas Department of Health, which is charged with determining if consumption of contaminated fish pose a risk to human health. If additional testing determines such a risk is
present, they can issue either fish consumption advisories or aquatic life closures for specific water bodies. The Texas Department of Health's Seafood Safety Division is charged with
surveillance of miles of oyster-harvesting areas along the Gulf Coast and has the authority to close bays and estuaries. This program is funded in part by a $1-per-sack fee paid by oyster
fishermen. No comparable revenue source is available for testing inland fish.
There is evidence that additional monitoring is warranted. In 1993 the EPA conducted a study on the types of
environmental problems to which Texas families living along the border are exposed. As part of the study, the EPA tested a carp caught by a Brownsville family from the Donna Reservoir. The
tests of the fish's tissue revealed PCB levels of 400 parts per million, or 200 times the recommended limit for human consumption.* When further tests of Donna Reservoir fish identified eight more fish contaminated by PCBs, the Texas Department of Health issued a fish-consumption advisory for the reservoir and its connecting canals. Ten more PCB-contaminated fish caught from an irrigation canal between the reservoir and the Rio Grande were found in January 1994. Following this study, the department banned any taking or consumption of fish in the area.*
PCBs have been banned in the United States since the late 1970s because they cause liver disorders and
developmental delays in infants. (The only exception to the ban is for use in electrical transformers.) To date, officials have been unable to identify the source of the PCBs found in the
Donna area.
While startling, the problems at Donna with PCBs are not unique.
Between 1990 and 2000, TNRCC officials have also identified nine segments around the state where elevated concentrations of PCBs in whole fish tissue are a concern.* In 1995 and 1996, following similar findings of high concentrations of PCBs in fish tissue, the Texas Department of Health issued aquatic-life closures of both Echo Lake and Mountain Creek Lake in the Trinity River Basin in the Fort Worth area. In 1990, the TDH issued aquatic life closures for four segments of the upper Trinity River for either PCBs and/or chlordane, a banned pesticide. These bans were reissued in 2002 following further testing, along with a fish advisory for Lake Worth. In June of 2001, the TDH reconfirmed that the Arroyo Colorado in south Texas near Brownsville should remain on its list due to elevated DDE, chlordane and toxaphene concentrations in fish tissue, most likely due to pesticides entering the stream by agricultural runoff. Problems with contaminated fish there have been present since at least the late 1970s.
Similarly, the TDH has issued fish consumption advisories in a number of lakes and creeks in East Texas in 1995
due to high mercury levels, most likely the result of deposition of air contaminants from coal-burning power plants and other industrial sources. Most recently, in 2002, several lakes in East
Texas, including Pruitt, Ratcliff, Meredith and Lake Daingerfield, were added to the list of advisories due to high mercury levels.
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LIST OF FISH CONSUMPTION ADVISORIES AND CLOSURES
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WATER BODY
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MOST RECENT DATE ISSUED
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SIZE
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POLLUTANTS
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SOURCE
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RESTRICTED OR NO-CONSUMPTION FISH ADVISORIES
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Ratcliff Lake
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2002
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Mercury
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Atmospheric Deposition
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Lake Meredith
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2002
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Mercury
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Atmospheric Deposition
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Lake Daingerfield
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2002
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1 mile
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Mercury
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Atmospheric Deposition
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Trinity River, from State Highway 34 Bridge to Cedar Creek Reservoir discharge canal
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2002
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PCBs, Chlordane, DDE
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Agricultural and Urban Runoff
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Arroyo Colorado, Llano Grande Lake and Main Floodway
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2001
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63 Miles
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Organochlorine Pesticides (DDE, Chlordane, Toxaphene)
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Agricultural and Urban Runoff
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Lake Worth
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2000
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4 miles
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PCBs
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Urban Runoff
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Lake Kimball
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1999
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Mercury
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Atmospheric Deposition
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Pruitt Lake (Black Cypress Creek)
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1999
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1 mile
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Mercury
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Atmospheric Deposition
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Gulf of Mexico
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1997
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3,879 square miles
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Mercury (King Mackerel Species)
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Unknown
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Caddo Lake
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1995
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26,800 acres
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Mercury
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Atmospheric Deposition
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Big Cypress Creek
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1995
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63 miles
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Mercury
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Atmospheric Deposition
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Toledo Bend Reservoir
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1995
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181,600 acres
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Mercury
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Atmospheric Deposition
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B.A. Steinhagen Reservoir
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1995
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13,700 acres
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Mercury
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Atmospheric Deposition
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Sam Rayburn Reservoir
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1995
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114,409 acres
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Mercury
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Atmospheric Deposition
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Welsh Reservoir
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1992
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1,365 acres
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Selenium
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Power plant
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Brandy Branch Res.
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1992
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1,240 acres
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Selenium
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Power plant
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Martin Creek Res.
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1992
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5,020 acres
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Selenium
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Power plant
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Houston Ship Channel/ San Jacinto River
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2001
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12 miles
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Dioxin, PCBs, Organochlorine Pesticides
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Paper mill, urban and agricultural runoff
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Houston Ship Channel
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2001
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6 miles
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Dioxin, PCBs, Organochlorine Pesticides
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Paper mill, urban and agricultural runoff
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Houston Ship Channel/Buffalo Bayou
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1990
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14 miles
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Dioxin
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Paper mill
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Upper Galveston Bay
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1990
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22 square miles
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Dioxin
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Paper mill
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Tabbs Bay
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1990
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3.6 square miles
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Dioxin
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Paper mill
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San Jacinto Bay
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1990
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2.1 square miles
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Dioxin
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Paper mill
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Black Duck Bay
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1990
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0.6 square miles
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Dioxin
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Paper mill
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Scott Bay
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1990
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1.7 square miles
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Dioxin
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Paper mill
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Barbours Cut
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1990
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0.2 square miles
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Dioxin
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Paper mill
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Burnett Bay
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1990
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2.7 square miles
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Dioxin
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Paper mill
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AQUATIC LIFE CLOSURES
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Lake Como
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1995
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15 acres
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Chlordane, PCBs, Dieldrin, DDE
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Urban runoff
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Fosdic Lake
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1995
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6 acres
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Dieldrin, DDE, Chlordane, PCBs
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Urban runoff
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Echo Lake
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1995
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17 acres
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PCBs
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Urban runoff
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Mountain Creek Lake
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1996
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2,710 acres
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Selenium, PCBs , Chlordane, Heptachlor, Epoxide, Dieldrin, DDE, DDD, DDT
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Unknown
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Upper Trinity River
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2002
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19 miles
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PCBs, Chlordane, DDE
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Urban runoff
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West Fork Trinity River
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2002
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22 miles
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PCBs, Chlordane, DDE
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Urban runoff
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Clear Fork Trinity River
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2002
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1 mile
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PCBs, Chlordane, DDE
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Urban runoff
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Lower West Fork Trinity River
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2002
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27 miles
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PCBs, Chlordane, DDE
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Urban runoff
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Donna Reservoir and Irrigation System
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1994
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333 acres
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PCBs
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Unknown
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Upper Lavaca Bay
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2000
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54.8 sq miles
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Mercury
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Spill
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Source: Texas Department of Health, Seafood Safety Division, Fish Advisories & Bans, 2003.
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