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Sewer pipes connecting TCAAP to Round Lake that originally contaminated the lake were sealed in the 1990’s. Becausethere is no public or private access to the lake, the contamination at Round Lake poses only an ecological risk and was not a priority for immediate action. The sediment contamination, however, must be addressed and a remedy approved prior to TCAAP’s removal from the NPL.As the responsible party, the U.S. Army must pay for any required remedy. 2011 Feasibility Study The Army has proposed a No Action remedy in which contamination is mitigated through the restriction of public and private access to thelake. The EPA has not approved a No Action remedy because itdoes not address the ecological damage. Also, the EPA and MPCA are concerned that a significant drought could lower the lake’s water level, similar to what has occurred at White Bear Lake in recent years, so that the sediment layer is exposed. If the sediment layer is exposed and dried, particles of lead or other contaminants could become airborne and affect human health. Little new sediment accrues on the lake, so contaminants are still inthe top layer of sediment on the lake’s bottom. Prior to identifying a remedy for Round Lake, a feasibility study must be drafted and approved. The feasibility study will define the problem and identify potential remedies including cost estimates for those remedies. Although feasibility studies have been drafted by the Army in the past, prior draft feasibility studies have not been approved by the EPA. After the most recent draft feasibility study was completed in April 2010, the MPCA and the EPA required the Army to do additional testingwhich was completed in January and February 2011.An agencymeeting is scheduled for June 2011 to discuss the results of the recent sampling. The next draft of a feasibility study is expected to be completed in Fall2011 at the very earliest. Public involvement usually occurs after the feasibility study and prior to the planning phase. In this case, however, due to the high level of citizen interest, a public meeting will likely be scheduled prior to the feasibility studybeing finalized. Potential Remedies for Sediment Contamination Options for a remedy vary from No Action to dredging the entire lake. Options such as installing a cap of manmade or natural materials are also possible. The eventual remedy selected may utilize a combination of remedies such as taking no action on parts of the lake, and installing a cap or dredging in other areas. If health risks are removed, the USFWSwould like to manage the lake so that it might be open to the public for activities such as fishing and bird watching. USFWS may want to occasionally draw down the water level in the lake by a foot or two to allow growthof vegetationin shallow areas. Vegetation would filter storm water runoff and provide wildlife habitat. The lake’s depth, up to 26 feet at some locations, ensures that the lake will always have open water. Residents expressed concerns that the lake couldbecome a wetland with little open water. They were concerned that dredging the lake could stir up sediment and that any activity on the lake could be harmful for wildlifeincluding turtles and bald eagles which have a nest on Round Lake. City of Arden Hills