responsiveness summary to public comments - US Environmental ...

Comment:
Page 12 of 40
1. Concerns were raised about EPA’s decision to list the above 5 waterbodies over the
Missouri Clean Water Commission’s (MCWC) recommendation. The MCWC indicated that
data did not exist to substantiate the original listing of these waters in 1998 and addressed this
fallacy or listing error.
2. MDNR’s comment letter stated that both the Little Osage River and Marmaton River
have very low DO levels during summer low flow periods, that there are no point source
discharges in the affected areas, and that there are no non-point-source contributions to the
stream during times when DO is a problem. The State believes that natural physical features of
this stream and its watershed are controlling DO and that it is in compliance with state standards.
Furthermore, historical fish distribution studies show that Osage Plains streams have always had
low fish diversity, indicating the natural level of aquatic habitat offered by these streams is poor
compared to other areas of the state.
EPA Response:
1. EPA did not add Little Drywood Creek in Vernon County (WBID 1325) to Missouri’s
2002 Section 303(d) list. EPA is retaining Clear Creek (WBID 1336) and North Fork Spring
River (WBID 3188) because no new data and/or information has been provided to EPA
demonstrating that these waterbodies should be removed from Missouri’s 303(d) list.
2. As previously discussed in Enclosure 1 to EPA’s April 29, 2003 decision letter to
Missouri regarding their 303(d) list, MDNR did not provide data to demonstrate that the
background values for DO are non-anthropogenic, nor modify its water quality standards to
include a site specific criteria or the designated use for Marmaton River or Little Osage River.
EPA, therefore, is retaining the Marmaton River and Little Osage River on Missouri’s 303(d) list
for low DO.
Stinson Creek
Comment: Available data are insufficient to justify listing of ammonia, biochemical
oxygen demand (BOD), and non-filterable residue (NFR). Ammonia-nitrogen samples at no
time exceed chronic ammonia water quality criteria for General Warm Water Fishery per 10 CSR
20-7.031-Table B. Of the 49 ammonia-nitrogen samples taken since 1991, six were above the
method detection level (0.05 mg/.L NH3-N). Available ambient data indicates that Stinson
Creek is not impaired. MDNR reached this conclusion and removed ammonia as a listed
pollutant.
EPA Response: Stinson Creek was originally listed in 1994 by MDNR as impaired due
to ammonia and BOD. The City of Fulton’s waste water treatment plant was the identified
source of impairment. Missouri removed ammonia as a pollutant of concern from Stinson Creek