HYDRO29057

• Permit No: M1988112
• IBM Index Class Name: Hydrology
• Doc Name: TABLE OF CONTENTS
• Media Type: D
• Archive: No

Appendix D, Cormnents from Rocky Mounmin Consultants. /nc., Hydrokinetics, lnc., & Hvdrodynamics,lnc. (Cont.) Page 16
Comment:
21. Section VLA.4.d. page 14. Item (il and page l5• first paragraph
The wording in this section is very confusing. Our interpretation of item (i) on page 14 is that the activity does not result in
significant degradation because it is not diluted by 100 to / or more at low flow. Hox~ever, the statement on page IS indicates
that item is (i) is not applicable since the dilution ratio is less than 100 to 1. We believe shat /tem (i) is applicable and should be
considered in the antidegradation review.
Response.•
/Jrhe flow ratio dilution were greater than /00 to 1, no further antidegradation review would be required. Since this is less than
the 100 to /ratio, the antidegradation considerations of (ii) and (iii) were further evaluated. /Jlhe reviex~ers are still unsure of
antidegradation requirements, thev should refer to the applicable regulations rejerenced in this section of the rationale. The
permit rationale reads correctly.
Commem:
22. Section V/.B.4.d, page I5. second pars ra h and Table VI-3
See Comment 5 concerning the use oJStation RS-5 to establish baseline load.
Table VI-3 only presents data jor a disclutrge aj 250 gprn jrorn Discharge Poim[ 00/. This analysis should be repeated jor all
discharge rates (i.e.. 400 gpm and 110 gpm). And, per our previous comments, this analysis also assumes no loading from the
seepage front.
Response:
See response to Comment 5.
The purpose ojshowing Table VI-3 x~as to demonstrate the general method applied in the determination of the appropriate
efJluen! standard jor each constituent. A similar method was applied jor the other discharges considered, as is indicated in
Appendix B. Also, see response to Comment Number /9.
Comment:
23. Section V/.B.4.e. page /7, fourh ~raeraph
An analysis must be performed to establish that radium and uranium are the species that contribute to the elevated gross alpha
activity observed in the West Pit.
Response:
See response to Comment 12 as x~ell as page 24 ojthe rationale.
Comment:
24. Section VI. B. S. page 18, second paragraph
The construction of the water treatment facilities, evaporation .system, amt other infrastructure on the West Pit cap, along xit/t
the re-rousing of ditch systems, may have altered the storm water lwndling in this area of the mine. Also, the operation oJthe
evaporation system may result in the build up of high concentration residues, sludges and waters on the mine cap. For these
reasons, we believe that the Facility's stormwater permit should be reviewed, at a ntinirmum.
Response:
The current draft of the CDPS permit was developed in support ojthe currently active implementation ojreclarnation and
remediation activities im the West Pit.
BMR/ currently holds a stormwater permit and tuts meet all of the reporting requirements of the stormwater permit. stormwater
is nor parr of the application jor this COPS permit currenty under consideration by the CDPHE. WQCD staff have reviewed the
stormwater management plan submitted by BMRI for their existing general stormwater permit.