DOE/ORO/2327 Oak Ridge Reservation Annual Site Environmental ...

Annual Site Environmental Report
discharges on the aquatic integrity of East Fork Poplar Creek. These tasks include (1) bioaccumulation
monitoring, (2) benthic macroinvertebrate community monitoring, and (3) fish community monitoring.
Data collected on contaminant bioaccumulation and the composition and abundance of communities of
aquatic organisms provide a direct evaluation of the effectiveness of abatement and remedial measures in
improving ecological conditions in the stream.
Monitoring is presently being conducted at five primary East Fork Poplar Creek sites, although sites
may be excluded or added, depending upon the specific objectives of the various tasks. The primary
sampling sites include upper East Fork Poplar Creek at East Fork Poplar Creek kilometer (EFK) 24.4 and
23.4 (upstream and downstream of Lake Reality, respectively); EFK 18.7 (also EFK 18.2), located off the
ORR and below an area of intensive commercial and light industrial development; EFK 13.8, located
upstream from the Oak Ridge Wastewater Treatment Facility; and EFK 6.3, located approximately
1.4 km below the ORR boundary (Fig. 4.27). Brushy Fork at Brushy Fork kilometer (BFK) 7.6 is used as
a reference stream in two tasks of the BMAP. Additional sites off the ORR are also occasionally used for
reference, including Beaver Creek, Bull Run, Cox Creek, Hinds Creek, Paint Rock Creek, and the Emory
River in Watts Bar Reservoir (Fig. 4.28).
Significant increases in species richness and diversity in East Fork Poplar Creek over the last two
decades demonstrate that the overall ecological health of the stream continues to improve. However, the
pace of improvement in the upper reaches of East Fork Poplar Creek near the Y-12 Complex has slowed
in recent years, and fish and invertebrate communities continue to be less diverse than the corresponding
communities in reference streams.
Fig. 4.27. Locations of biological monitoring sites on East Fork Poplar Creek in relation to the
Oak Ridge Y-12 National Security Complex.
The Y-12 National Security Complex 4-55