FEIS - Tahoe Regional Planning Agency

RESPONSE TO COMMENTS ON THE DEIS
B o u l d e r B a y C o m m u n i t y E n h a n c e m e n t P r o g r a m P r o j e c t E I S
determined by comparing this storm volume (13,201 cubic feet) to the 20yr/1hr storm
total runoff volume (8,517 cubic feet - support calculations are provided in DEIS
Appendix G). See Appendix AB for DEIS Appendix G supplemental information for
predicted total sediment, fine sediment and nutrient load reductions.
Comment 332-s: Comment Summary - The EIS should quantify fine sediment ( 50% of total sediment
load for granitic soils and JBR data reported levels as high as 90%. Since
Alternatives C and D aim to capture, convey and infiltrate the 100yr/1hr storm total
runoff volume, then 97 - 100% of the total sediment can be captured and infiltrated
for this storm volume. The EIS states a more conservative reduction estimate of
90%, but modeled results for example water year 1993-1994 predict higher
reductions in total sediment. See Appendix AB for supplemental analysis of
predicted load reductions, including fine sediments of 20 microns and less.
Please see response to comment 129-a for additional information on the definition of
fine particle size.
Comment 332-t: Comment Summary - Requests additional water quality monitoring data.
See Appendix AB for the supplemental surface water quality analysis, which
incorporates data collected for the DRI Brockway Project Area Stormwater Runoff
and Characterization Study and Upper Cutthroat Infiltration Testing and Stormwater
Runoff Study (Heyvaert et al. 2008) into the LSPC model to predict existing total
sediment loads and proposed reductions based on the 20yr/hr and 100yr/1hr storm
events.
Comment 332-u: Comment Summary - Utility undergrounding listed as a benefit in Alts C and D, but
not A, B and E. But the work is completed and should be listed as a benefit in all
Alternatives.
Please see response to comment 322-ac.
Comment 332-v: Comment Summary - The EIS claims (p. 4.2-16) that coverage mitigation can use
ROWs under Code 20.5; but is not allowed under 20.3B. Provide the appropriate
supporting code and language, and adjust coverage calculations as needed.
The reference to TRPA Code Section 20.3.B is incorrect and should have been Code
Section 20.3.D. Code Section 20.3.D defines the method for calculating land
coverage. Subsection 20.3.D.1(b) doesn't allow the existing Washoe County ROW
lands to be used for determination of base allowable land coverage. Therefore, the
existing ROW was excluded from the project area for determination of allowable
base land coverage. Because the ROW will be rescinded for the project to go
SEPTEMBER 8 , 2010 HAUGE BRUECK ASSOCIATES PAGE 8- 135