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Section 319
NONPOINT SOURCE PROGRAM SOCGESS STORY
Educating Residents and Collecting Household Hazardous Waste Items
Reduces Legacy Pollutants in Fosdic Lake
\A/citprhnH\/ Imnrnx/prl 'n ^^ t'ie ^exas Department of State Health Services (DSHS)
banned the possession of fish taken from Fosdic Lake in Fort
Worth because of high concentrations of potentially harmful chemicals in the fish tissue.
As a result, Texas added Fosdic Lake to its Clean Water Act (CWA) section 303(d) list of
impaired waters in 1996. In response to the ban, local, state and federal agencies coordi-
nated data collection and education/outreach efforts in the city of Fort Worth to reduce
the inflow of harmful chemicals into area lakes. Recent monitoring shows that the pollutant
levels in fish from Fosdic Lake have diminished sufficiently to allow for their safe consump-
tion, prompting DSHS to lift the fish possession ban in 2007. The lake was removed from the
2008 impaired waters list for dichlorodiphenyldichloroethylene (DDE), dieldrin and chlordane.
Problem
Fosdic Lake (Figure 1) is a 7-acre manmade
impoundment (segment 0806A) on a tributary of
the West Fork Trinity River in Tarrant County. Built
between 1909 and 1912, the lake drains a 262-acre
residential watershed in east Fort Worth. In 1995
lake fish tissue monitoring data showed elevated
levels of several legacy pollutants, including chlor-
dane, DDE, dieldrin and polychlorinated biphenyls
(PCBs), prompting DSHS to issue a ban on the
possession of all fish species from Fosdic Lake. As
a result, the Texas Commission on Environmental
Quality (TCEQ) placed Fosdic Lake on its 1996 CWA
section 303(d) list as impaired for its designated
fish consumption use.
Legacy pollutants are substances that have been
banned or restricted but remain in the environ-
ment. Chemical substances like chlordane, DDE,
dieldrin and PCBs were widely used as pesti-
cides, coolants and lubricants from about 1946
until they were eventually restricted between
1972 and 1988. In spite of the restrictions on the
substances, area soils continued to be contami-
nated through direct application, leaks and spills.
Extensive urban development from the late 1950s
until the early 1990s caused contaminated soils to
erode and accumulate in Fosdic Lake. The pol-
lutants then entered the food chain and became
concentrated in fish tissue.
Figure 1. Fosdic Lake is in East Fort Worth, Texas.
On November 17, 2000, TCEQ and the U.S.
Environmental Protection Agency (EPA) approved
a total maximum daily load (TMDL) for Fosdic
Lake to address legacy pollutants in fish tissue.
The endpoint of the TMDL was to restore the fish
consumption use by meeting the DSHS' criteria for
contaminant levels.
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Project Highlights
The Fort Worth Environmental Management
Department (FWEMD) operates the Environmental
Collection Center (ECC), a permanent, year-round
facility that accepts household hazardous waste
from residents of Fort Worth and other areas. In
consultation with TCEQ and EPA, the ECC modified
its record-keeping system to track the amounts of
legacy pollutants collected at the center. The city
used the information as a measure for evaluating
its pollution prevention program and targeting its
educational efforts.
As part of the TMDL effort, TCEQ collaborated with
the U.S. Geological Survey (USGS) in 2004 to collect
and analyze sediment and runoff samples from the
watershed to evaluate the loading of legacy pollut-
ants and to identify trends and sources of the pol-
lutants. The TMDL collaboration effort also included
collecting fish tissue samples, an effort funded in
part by a CWA section 319 grant. The goal was to
develop the quantitative risk characterization that
eventually became the basis for the revised health
risk assessment that DSHS adopted in 2008.
Results
Pollution prevention and source control practices
such as the public education and household hazard-
ous waste collection programs implemented by the
City of Fort Worth contributed to the reduction of
pollutants. The City's educational program resulted
in an overall 21 percent increase in the use of its
permanent household hazardous waste facility. As
of 2006, the ECC had collected and logged more
than 8,000 pounds of materials containing legacy
pollutants. The educational program was also highly
successful in informing the public about the quality
of urban lakes and the possible public health and
environmental risks of potential contaminants. The
combination of these investigations, management
activities, and the natural attenuation of the pollut-
ants has proven to be effective for Fosdic Lake.
Through 2006, sampling of residential stormwater
outfalls showed that legacy pollutants continued
to be present in urban runoff. Recent fish tissue
monitoring data, however, indicated that the pollut-
ant levels in fish from Fosdic Lake had diminished
sufficiently to allow for their safe consumption,
prompting DSHS to lift the fish possession ban
in 2007. According to a January 15, 2008, DSHS
article, fish tissue monitoring showed that, with
the exception of PCBs, concentrations of legacy
pollutants were in compliance with the target
health assessment comparison (HAC) values in the
TMDL (Figure 2). As a result, TCEQ removed the
impairment designation for chlordane, dieldrin and
DDE in 2008. Although there has been a distinct
downward trend in PCB concentrations, levels
remain sufficiently elevated to warrant a consump-
tion advisory and impairment designation.
0.4
0.35
0.3
0.25
i
, 0.2
0.15
0.1
0.05
0
Fosdic Lake
Contaminant Concentrations in Fish Tissue
-•Chlordane nDieldrin nDDE • PCBs(Aroclor 1260)
1995 2001 2005
nd = All samples less than the detection limit;
PCB detection limit decreased in 2005
HAC = Health-Based Assessment Comparison Value
* The Chlordane HAC value was calculated using the 1995 oral RfD value
(0.00006 mg/kg-day).The HAC values calculated for Dieldrin, DDE, and
PCBs were 0.117,1.167, and 0.047mg/kg respectively.
Figure 2. Concentration of legacy pollutants in fish tissue,
1995-2005.
Partners and Funding
Funding for this project involved multiple in-kind
sources and the cooperation of many partners. The
City of Fort Worth contributed to the project by
conducting public outreach and collecting hazard-
ous household waste. The USGS investigated the
status and trends of legacy pollutants in sediments.
TCEQ and the USGS each contributed $39,000 (for
a total cost of $78,000) for the joint investigation.
TCEQ contributed approximately $25,000 in EPA
CWA section 319 funds to support DSHS' analytical
expenses for the most recent fish tissue analysis.
DSHS matched the grant with salaries and in-kind
services to collect the samples and develop the risk
characterizations.
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-11-00100
September 2011
For additional information contact:
Jack Higginbotham, Tim Cawthon or Roger Miranda
Texas Commission on Environmental Quality
E-mails: Jack.Higginbotham@tceq.texas.gov;
Tim.Cawthon@tceq.texas.gov;
Roger.Miranda@tceq.texas.gov
Phone: 512-239-1000
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