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TENNESSEE
The Tennessee Nonpoint Source Program continues to work, watershed by
watershed, to mitigate nonpoint source problems. Tennessee strives for the
holistic approach-- restoring riparian zones and wetland habitat along with
stream and lake restoration and public education.
Tennessee Cleans Up Polluted Abandoned Mine Lands in Bear Creek
A high potential for health hazards from contaminated groundwater on
hundreds of acres of unreclaimed strip-mined lands gave Tennessee good reason
to clean up the area. With a combination of section 319 and state Abandoned
Mine Lands Program funds, a reclamation program of monitoring and best
management practices to improve water quality is underway in the Bear Creek
watershed. The watershed in northcentral Scott County flows north into
Kentucky. There, it joins the Cumberland River's Big South Fork, which Kentucky
has designated a Wild and Scenic River. The National Park Service currently
owns the Big South Fork National River and Recreation Area, - encompassing
73,748 acres in Tennessee and 30,430 acres in Kentucky.
Bear Creek drainage enters the Big South Fork just upstream from a
freshwater mussel bed containing numerous species, two of which are endangered.
The bed contains the world's highest concentration of one endangered
species--the little-winged pearly mussel (Pegias fabula)- -that inhabits cool,
clear, high-gradient streams.
Although about 100 families draw their water supply from the groundwater,
test data for most pollutants were practically nonexistent. However, county
extension service and local officials reported a high potential for health
hazards from the contaminated groundwater. Cleanup was targeted for some 689
acres of partially reclaimed land--strip-mined for coal in 1973 and mined again
in 1977. The target area also includes unmapped deep mines, abandoned oil and
gas wells, an 80-acre industrial dumping site that may be contaminating the
groundwater, and a 70-acre abandoned surface coal mine that has heavily eroded
spoil banks and acid mine drainage. Other water quality impairments include
heavy metals, sediment, and decreased dissolved oxygen.
Two active players in cleaning up the Bear Creek watershed are the NPS
Program and the Abandoned Mine Lands (AML) Program, both part of the Tennessee
Department of Environment and Conservation (TDEC). The NPS Program has directed
all water quality monitoring, including mapping potential groundwater use
areas, follow-up monitoring at selected well sites, and monitoring before and
after the installation of BMPs. The AML program will provide special water
quality sampling for heavy metals, pH, and acidity during BMP construction. In
addition, the State Division of Lab Services is checking for variations in the
aquatic biological community as a sign of improvement at five sites. The
Kentucky NPS Program is also evaluating water quality. The AML program has
proposed BMPs and reclamation action, which calls for reshaping approximately
120 to 160 acres to establish controlled drainage. The reclamation agenda also
includes installing subsurface limestone drains (anoxic limestone trenches) and
creating buffer wetlands to route acid mine drainage. The anoxic trenches will
raise the pH of acidic runoff, previously at 2.5, to between 6.0 and 6.5. The
buffer wetlands enhance the aquatic community by increasing metal oxidation and
pH. During the next two years, this procedure will be used on other sites
identified in the upper watershed.
The BMPs were partially funded with three $25,000 section 319 grants to
Tennessee in FY 1990, 1991, and 1992. The AML Program has supplied from $75,000
to $140,000 each year for BMP funding. The NPS Program also used section 319
funds, totaling $130,000, for pre-and post-BMP monitoring. Tennessee recently
received an additional $375,000 in section 319 funds to complete the project
and install the final demonstration BMPs. The state AML Program will match
these funds. A special $15,000 U.S. Fish and Wildlife Service grant will
support water quality monitoring near the endangered mussel habitat.
Initial reclamation demonstration projects--land reshaping reclamation,
installing anoxic drains, and constructing artificial (buffer) wetlands--were
completed at the end of FY 1992. TDEC monitored four storms for chemicals at
Big South Fork River and analyzed sediment and water quality from Bear Creek's
east and west branches. This pre-BMP data will be used to show water quality
improvements after all BMPs are installed and post-BMP monitoring is complete.
Initial monitoring has confirmed the presence of several toxic metals,
including mercury. A pH monitoring effort has indicated improved pH in water
leaving the artificial wetlands. This may correlate to a potential reduction in
toxic metals in the creeks. Outreach efforts have also drawn together various
federal, state, and local pollution control agencies, which have exchanged
valuable technology at on-site visits and presentations at meetings and
conferences.
Animal Waste Systems Improving Habitat
Concern over nonpoint source water pollution from livestock production
prompted Tennessee to target five subwatersheds in the Nolichucky River
watershed. This area includes Greene and Washington counties, the state's
largest milk producing areas. Much of the problem centers on animal waste from
waiting or milking areas washing into the streams. To stem this pollution
source, the Tennessee Department of Environment and Conservation has worked
with other state and federal agencies and farmers to install animal waste
systems. These systems store the waste, which farmers later use to fertilize
crops.
For FY 1990 and 1991, the monies from a section 319 grant and other
agencies totaled $392,813 to fund BMPs in the Nolichucky River watershed.
Section 319 monies, through a contract with Tennessee Department of
Agriculture, totaled $7,806. The majority of the BMP monies came from special
ASCS funding. Although the 319(h) dollars for BMP implementation represented
less than 2 percent of BMP funding from the FY 1991 and 1992 grant monies, an
additional $50,000 of 319(h) money was spent for water quality monitoring for
BMP effectiveness.
In testing the effectiveness of BMPs a year after installation, the
Tennessee Department of Health found statistically valid improvements in
benthic habitat in two subwatersheds.
The state determines improvement by using a number of biotic indexes. The
North Carolina biotic index (NCBI) and Hilsenhoff biotic index (HBI)--which
measure the number of pollution tolerant, intolerant, and facultative organisms
in the watersheds --are two examples. Tolerant species are able to withstand
and thrive in the nutrient-rich environment of a polluted watershed. Intolerant
species cannot withstand a nutrient-rich environment, and increase only when
pollution decreases. Facultative organisms can live in both nutrient-rich and
nutrient-free environments.
BMPs in Jockey Creek, located in the Big Limestone watershed, were
installed between August 1990 and - February 1991. Biological sampling began in
October 1990, and by July 1991 the benthic community showed improvement.
Although Jockey Creek showed no biological change from fall to spring, an
increase in the number and diversity of intolerant Ephemeroptera (mayflies)
showed some improvement in water quality during the summer. However, the
facultative Stenonema species remained the dominant mayfly, indicating that
some nutrient enrichment was still present in the waters.
The Ephemeroptera, Plecoptera, Trichoptera (EPT) taxa richness (three
orders representing the majority of intolerant species in the water) showed no
change between seasons at Jockey Creek, which has the lowest value (number of
taxa) of any of the Big Limestone test sites. However, EPT taxa richness for
the rock habitat increased from four taxa in the fall and spring to seven taxa
in the summer. This increase in intolerant species indicates an improvement in
water quality. In addition, the percent of tolerant Chronomids and
annelids--which survive in nutrient-rich waters-- dropped dramatically from a
spring high of 57 percent to a summer low of 9 percent. All of the previous
factors indicate improvement in Jockey Creek's benthic habitat since two animal
waste systems were installed. Additional improvement over time will indicate if
this is a trend.
Puncheon Camp Creek in the Lick Creek subwatershed, one of the study's
smallest and most severely stressed streams, has also shown improvement after
animal waste systems were installed in December 1990 and January 1991. Although
still stressed, the benthic community showed steady improvement in May and July
1991.
The HBI and NCBI showed that the number of facultative species consistently
increased throughout the spring and summer. While no new intolerant species
appeared, the number of Perlesta (a facultative Plecotera [stonefly]) -
increased during the summer. The fall 1990 sample showed a very low EPT
richness of two in Puncheon Camp Creek. However, the intolerant species
improved dramatically to 10 in the spring, with a small summer decline to
eight. While tolerant Chironomids and annelids were abundant--57 percent in
fall 1990 and reaching a peak of 72 percent in the spring--their presence
dropped off to 12 percent in the summer, indicating water quality improvement.
These measures show that Puncheon Camp Creek's benthic community structure may
be improving. Tolerant organisms appear to be on the decline while facultative
species are moving in to fill the habitat. However, the habitat remains
severely impacted. Permanent improvement can be expected only over time as the
habitat is restored. Continued analysis will show, in fact, whether the
improvement is consistent.
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