1995-04-27_AgendaPacket - Laserfiche WebLink

Home

Response to EAW Comments Apri127, 1995 Page 2 Comment: The project site was identified as a Type 2/6 wetland within the EAW and should be considered a Type 3 wetland. Response: The predominant vegetation within the subject wetland complex is reed canary grass. This species is common within Type 2 basins and is also present within Type 3 wetland complexes. The basin may be better described as a dry Type 3 wetland or a wet Type 2 wetland complex. Comment: The dredge spoils should be tested for contaminants to ensure toxic agents are not exported offsite to other areas. Response: Figure 1 on Page 4 of the EAW Appendix shows the tributary watershed to the project location. With the exception of a relatively small area in the extreme southwest portion of the subwatershed and Highway 36, the tributary area is heavily dominated by residential land use. There are no large industrial or commercial land uses which are generally associated with problematic levels of heavy metals. The dominance of residential land use would indicate the probability of high levels of toxic agents are relatively low and testing for these compounds is not deemed necessary at this time. Comment: Figure 3 of the EAW shows two small ponds in the southwest corner of the project area. How are these ponds related to the project? Response: Figure 3 was generated early in the project design process and was a schematic rendition of the project as proposed in the EAW. The figure was included as an aerial photo exhibit in the EAW and was meant to convey the existing land use and wetland conditions. The ponds shown on this exhibit are irrelevant to the project as described in more detail elsewhere in the EAW document. Comment: The EAW does not indicate how the constructed ponds will be maintained upon project completion. Response: The ponds will have to be periodically dredged to remove the deposited material in order to restore the system to its intended removal efficiency. The frequency of maintenance is related to the size of the project. In other words, the ponds could be overexcavated to allow for additional sediment storage which would reduce the maintenance frequency, but increase the area of disturbance associated with the proposed construction. Conversely, the pond size can be minimized but the maintenance frequency would increase. The present design is based upon the Nationwide Urban Runoff Program (NURP) detention basin standards as described in the GLWMO Water Quality Study. The rate of sedimentation will be monitored annually and sediment will be removed as necessary.