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Page 4 of 4 From: Jim Knowles [mailto:james.knowles @jdknowles.com] Sent: Friday, December 19, 2008 9:13 AM To: Peterson, Cami L - DNR; 'Eric.Heggelund @Wisconsin.gov' Subject: Wetland Site Review Good Morning, Eric and I talked briefly this morning about a site in the Town of DeForest that has a need for us to review a wetland line that was approved by both the WDNR and COE in 1998. At the time the approvals were issued the site was farmed so the wetland boundary was determined primarily upon soils and hydrology. Today, the site is vegetated with a mixture of upland and wetland plants which give the impression that the wetland line has moved upslope. I looked at the site this past week, augured three test holes down to 30 inches along the slope from high to low -from 60 feet upslope of the mapped wetland line down to the wetland line, and found approximately 24 inches of colluvium deposits over the native soils. I did not find any signs of redox in the colluvium layer which suggests to me that the site wetland line has not moved much if at all. However, some of the vegetation (reed canary grass and red osier dogwood) suggests that the wetland line has moved. To really answer this question we need to establish at least four transects and a minimum of 4 sample points per transect and get a very good look at soils. The vegetation on the site is quite typical and easy to identify: reed canary grass, red osier dogwood, common milkweed, Canada goldenrod, wild carrot, and Kentucky blue grass. Ground frost is all but absent due to the nice carpet of snow. I only found water at about 24 inches at the sample hole located adjacent to the former wetland line. Interestingly, there was about 24 inches of colluvium over the native soils and hydrology at the lowest sample point. Since the site was last mapped much of the upland areas have been developed so nearly all of the surface water runoff that once passed overland and into the wetland complex has been rerouted away from the site and now flows through a series of storm sewers and detention ponds. Sanitary sewer and water main construction may have likely interrupted groundwater flow as well. I would suspect that at a minimum that the site in question is actually drier than when first mapped in 1998. Finding ground water at 24 inches beneath the ground at the old wetland line did not surprise me. If we can meet at the site on Tuesday morning and do the work together I think we can get the line resolved quite quickly. One last item: Dane County is asking this be done because the land owner has a permit to construct a new multi-family building on the property. With the change in wetland setback criteria at the County level, the location of the wetland line must be verified for this reason alone. If we can work together to get this addressed before the ground frost shuts down the growing season that would be helpful to the County and to the land owner. Jim 1/28/2009