responsiveness summary to public comments - US Environmental ...

EPA Response:
Page 10 of 40
1. EPA had reviewed water quality data from a monitoring station located on the
Missouri/Kansas stateline. This data was derived from the Kansas TMDL which was completed
for fecal coliform and approved by EPA on August 28, 2001. Kansas used the same data to
determine that the portion of Indian Creek that runs through Kansas is impaired by fecal
coliform. The data confirmed 16 exceedences of Missouri’s numeric criterion during the
recreational season. Also, the geometric means of the data were exceeded for years 1998, 1999,
and 2001. EPA concluded that any reductions in coliform bacteria in Indian Creek, after crossing
the stateline into Missouri, would be insignificant and, therefore, would not be expected to meet
Missouri’s standard of 200 colonies/100 mL.
2. Given the magnitude of the exceedences, regardless of stream flow, EPA believes that
the whole body contact recreational use of Indian Creek is impaired.
3. EPA’s TMDL program will coordinate with KDHE regarding any proposed reopening
of the Kansas TMDL for Indian Creek to address needed modifications to the fecal coliform
endpoint in order to ensure that downstream water quality criterion is met.
4. EPA originally listed Indian Creek as being impaired for pH because DMRs obtained
from MDNR listed the data from Site #5 as “upstream data.” MDNR commented that data
which EPA reviewed did not agree with data in MDNR’s possession. Upon further review of pH
data provided by the Department of Energy (DOE), EPA concluded that outfalls and sampling
locations were misidentified in DMRs. EPA determined that the values in exceedence of the
State’s pH criterion from Site #5 were not in-stream values, but were taken from water used for
non-contact cooling, and not ambient stream data from Indian Creek. Furthermore, now having
discounted Site #5, for the station upstream of outfalls 003 and 004, only one out of 75 pH
measurements exceeded 9.0 units. Given this new information, EPA is removing pH as a cause
of impairment of Indian Creek from Missouri’s 303(d) list with respect to impairment for pH.
River Des Peres
Comment:
1. The dissolved oxygen (DO) data used by EPA to determine exceedences of the State’s
DO criterion of 5.0 mg/l was from a U.S. Geological Survey (USGS) sampling site located by
Herman Park in University City. This is not a classified section of stream; therefore, the numeric
standards for aquatic life do not apply. The classified section where the standard applies is
approximately 12 miles downstream from the USGS sampling site;
2. Data was provided to EPA by Stream Team 1437. Stream Team 1437 monitors two
sites along the southwest branch of River Des Peres which forms the north border of Ruth Park