Abstract
We review long-term changes that have
occurred in factors affecting water quality in East Fork
Poplar Creek (EFPC; in East Tennessee) over a nearly
25-year monitoring period. Historically, the stream has
received wastewaters and pollutants from a major United
States Department of Energy (DOE) facility on the headwaters
of the stream. Early in the monitoring program,
EFPC was perturbed chemically, especially within its
headwaters; evidence of this perturbation extended downstream
for many kilometers. The magnitude of this perturbation,
and the concentrations of many biologically
significant water-quality factors, has lessened substantially
through time. The changes in water-quality factors resulted
from a large number of operational changes and remedial
actions implemented at the DOE facility. Chief among
these were consolidation and elimination of many effluents,
elimination of an unlined settling/flow equalization basin,
reduction in amount of blow-down from cooling tower
operations, dechlorination of effluents, and implementation
of flow augmentation. Although many water-quality
characteristics in upper EFPC have become more similar to
those of reference streams, conditions remain far from
pristine. Nutrient enrichment may be one of the more
challenging problems remaining before further biological
improvements occur.
