I am writing in response to the Public Notice regarding the proposal by the Division of Waste Management to approve the Groundwater Assessment Report submitted by Waste Management of Kentucky, LLC regarding the detection of trichloroethene in well CKD06.
For the reasons stated below, KRC requests that the agency reevaluate the Groundwater Assessment Report and that the Division not approve any termination of groundwater monitoring or closure of monitoring wells until these issues are fully resolved. My concerns after reviewing the 2005 Ground-Water Quality Assessment Report are these:
1. From the reported ground-water elevation levels, it appears that on several occasions over the years, the static water level of supposedly downgradient water wells exceeds that of ?upgradient wells. For example, the 6/24/81, 11/19/92, 4/25/96, 3/11/97, 11/20/97, 1/23/98, 5/18/98, the water level is higher in at least one of the downgradient wells than an upgradient well.
All other things being equal, water will tend flow from higher to lower head, and in an alluvial aquifer, will flow towards the river or from the river depending on the elevation of the river pool relative to the aquifer. The alluvial aquifer, according to published data, flows generally southwest beneath Louisville, following the river. The variations in the water level measurements for the various wells raises a concern that the flow under the site may not always be as it has been mapped in the report.
A more comprehensive mapping of the aquifer flow, taking into account these variations is needed to provide assurance that the variations in flow patterns has been considered. A mapping of the aquifer that incorporates each of the various data collection events is needed to provide confirmation that the site hydrogeology is fully understood and that the groundwater monitoring wells have been properly located to intercept any plume. Alternatively, the mapping will help identify any additional groundwater monitoring points needed to provide assurance that sampling under all flow conditions has been conducted and that the samples demonstrate that the trichloroethene is no longer under the site.
2. KRC is concerned as well that the report does not identify the source of the trichloroethene. Obviously, the presence of any solvent in groundwater samples from beneath an inert landfill is of concern, since wastes containing such solvents are not appropriate to that type of land disposal facility. To the extent that the source of the trichloroethene is landfilled waste, a question is raised as to what the specific source of the waste was and whether there is additional waste that may release such constituents in the future. If the source is not the landfill but rather some other disposal activity (such as the adjoining landfill or other industrial properties) then that should be demonstrated to be the case and appropriate action taken to remove that source and prevent further releases. Absent some indication (which may be in other documents but was not apparent in this report) that the source has been identified and appropriate measures taken to prevent future releases from that source, complete abandonment of monitoring is not appropriate given that the past detection is potentially indicative of disposal of constituents of concern in a landfill not designed or authorized to manage such wastes.
KRC requests that the agency reevaluate the report and address these two concerns prior to finalizing the agencys position concerning the request to discontinue the groundwater monitoring and to abandon the wells. Thank you for your consideration of these matters.
cc: Tony Barbush WM