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the growth of invasive aquatic species in this reach (see simulated photo). The current condition <br />of the channel is a low gradient, wide channel that runs slow and shallow during the summer. <br />This re-aligning and configuration change to this section will provide some insight to future <br />work within the channel as we continue riparian enhancements in this waterway. <br />For the purposes of developing the affected wetland and OHW (and below) quantities, we settled <br />on a conservative line for the delineations (see "Affected area cross section"). This line is the <br />wetted perimeter approximately 2' above the observed OHW lin~ defined by vegetation. The <br />selected line will likely provide a higher effected area and a higher fill / removal quantity than <br />what a new°delineation line would show. It's likely the more appropriate wetland delineation <br />line would fall less than a couple of feet above the OHW line as this has been the case in most of <br />our larger trapezoidal channels and ponds. That line being delineated as the "wetted" zone. <br />Soil compaction; It is anticipated that this work will be accomplished by large heavy equipment <br />(excavation hoes) and dump trucks. These hoes will operate on tracks working along the banks, <br />thus spreading their weight over the ground reducing soil compaction. All vehicle travel will be <br />confined and after construction, those corridors will be scarified to loosen compacted soil as <br />needed. Once the site is excavated, heavy equiprnent (graders and cats) will be used to perform <br />final grading to designed contours. <br />Soil Qualit~ In our initial discussions about the partnership between Delta Ponds and Golden <br />Gardens ponds, we discussed the introduction of potential unwanted contaminants. As we looked <br />closer at the historic use of the site, and acquired water quality samples (see tables) from Golden <br />gardens ponds we realized that the soil would be free of contaminants and that the major concern <br />for any type of contamination might be the introduction of invasive plants not found yet at Delta <br />Ponds. Of highest concern would be the accidental introduction of Knapweed and Yellow <br />Primrose. Both plants exist at Golden Gardens Ponds but have yet found their way to Delta <br />Ponds. We determined the best way to avoid this was to separate soil in proximity to the invasive <br />plants (leaving it on site and in upland fills) from soil not contaminated. Upland fill areas will be <br />the repository for these soils with potential root or seed contamination from invasive plants. Soil <br />identified as "clean" will be relocated to Delta Ponds. <br />Traffic impact: Project specification will require the majority of Excavation (truck) traffic to exit <br />to the North across an access agreement and use Clear Lake Rd. to Hwy 99. This will avoid <br />nuisance traffic in local neighborhoods South of the ponds. Light vehicle traffic will be allowed <br />to travel to the South. <br />Erosion and dust control: This project will abide by requirernents of the City of Eugene Erosion <br />control ordinance even though it is outside of the City boundaries. The City of Eugene is <br />regulated by NPDES permits and this project will be administered as if it was within city <br />boundaries. Construction work will be monitored by city inspection staff on a daily basis. Dust <br />will be abated by water trucks. Erosion control will be accomplished so that it meets current <br />requirements of the erosion ordinance. Separation by mulch berms and other controls will be <br />installed to avoid any soil erosion from entering the water. Sediment settling devises will be <br />installed to trap and settle water before it is allowed to continue down stream. As final <br />contouring is accornplished, native grass seed and organic mulch will be applied to the newly <br />disturbed soil. This will provide good ground cover for erosion protection and allow the site to <br />begin its healing process. Plantings of native plants and trees (see list) will be used to re-vegetate <br />Page 11 <br />