Bill Reetz, Kansas Department of Health and Environment told the Manhattan City Commission Tuesday night that the State was willing to spend up to $1 million to protect the City water wells.

Here is a memo given to the Commission telling of the problem:

BACKGROUND

In October 1999, the City of Manhattan’s Utilities Department initiated a new voluntary Well Field Water Quality Monitoring Program for the 16 public water supply wells in the City of Manhattan’s Well Field and the six operating water reservoirs. This monitoring program was initiated as a follow up to earlier analysis by the Bureau of Environmental Remediation (BER) of the Kansas Department of Health and Environment (KDHE), which identified a presence of a few Synthetic Organic Compounds (SOCs) and Volatile Organic Compounds (VOCs) in groundwater samples from Public Water Supply (PWS) wells #12 and 13.

Water quality parameters including SOCs and VOCs are evaluated on a quarterly basis in the Well Field Water Quality Monitoring Program. The monitoring program has collected data from PWS wells on a quarterly basis since October 1999. However, due to maintenance schedules and repairs not every well was necessarily sampled each quarter. Evidence of the presence of low levels of hydrocarbon contaminants in some of the PWS wells has been gathered through the City’s Well Field Water Quality Monitoring Program for pesticides, SOCs, and VOCs. The detected contaminants, however, were mostly below the federal and state Maximum Contaminant Levels (MCL).

The water from the City of Manhattan PWS wells is pumped to the City’s Water Treatment Plant located along Tuttle Creek Boulevard, to the west of the well field. Hence, the finished water that actually comes out of the tap in Manhattan is blended from the City’s 16 PWS wells.

The City of Manhattan’s drinking water meets or surpasses all federal and state drinking water standards. Furthermore, the level of contaminants in PWS #13 showed a positive decreasing trend. Motivated by its concern about the safety of the public water supply source, the Utilities Department staff met with KDHE staff for technical consultation regarding the best means to deal with the contamination of the PWS Well #13.

DISCUSSION

City of Manhattan Utilities Administrative personnel have met with representatives from the Kansas Department of Health and the Environment (KDHE) and Bluestem Environmental Engineering on a number of occasions since December of 2000 to discuss the possibility of developing a ground water treatment system. The treatment system would be used to remove methyl tert-butyl ether (MTBE) and other hydrocarbon compounds such as benzene, which have impacted the ground water at PWS wells #12 and #13.

In order to construct a treatment system, additional easement is necessary to accommodate the building that will house the Granulated Activated Carbon (GAC) water treatment system.

In order to protect the City of Manhattan’s Well Field from further hydrocarbon contamination, the KDHE Bureau of Remediation is currently operating in-situ remediation operations at two local gasoline stations located southwest of the well field. Three remediation processes are being used to mitigate or eliminate the contamination. These processes include in-situ air sparging (IAS) techniques, soil vapor extraction (SVE) techniques and free product capture and collection. The IAS process rehabilitates ground water while the SVE process rehabilitates soil. Both the IAS and SVE processes are being used at both sites. The free product capture process collects and removes released gasoline from the top-most layer of the groundwater.

The position of PWS #13 is along the western edge of the well field, between the contaminant source areas and the other 15 Public Water Supply wells. Groundwater generally flows toward the well field from the southwest. The installation of the Granulated Activated Carbon water treatment system facility at PWS #13 is expected to reduce or eliminate hydrocarbon contaminants from the remaining PWS wells by acting as a capture point for the migrating contaminants. The GAC system is composed of two 20,000-pound vessels filled with granulated activated carbon. Water from the well is directed through the vessels prior to entering the transmission line to the Water Treatment Plant. As the ground water passes through the activated carbon, the carbon absorbs the hydrocarbon contaminants.

KDHE will provide the funding for the GAC ground water treatment facility. KDHE has assumed the costs that will be incurred by the assumption of the necessary land acquisition, materials and construction costs, and the initial operation costs. The operation costs are budgeted to include electrical, natural gas, and sampling costs for the initial two years of operation as well as one change-out event of the granulated carbon, should it be necessary.

Once construction begins, it is estimated that 11-12 weeks will be necessary to complete the installation of the GAC vessels and the construction of the containment building. Upon completion of the installation, both the KDHE and Bluestem Environmental Engineering have committed themselves to training City of Manhattan Utilities personnel in the proper operation and maintenance of the facility.

In order to gauge the effectiveness of the GAC system in relation to removal of the hydrocarbon contaminants, a water-sampling program will be needed. Sampling will be required by the KDHE weekly for the first month of operation, monthly thereafter for the first quarter of operation, and then quarterly for the remainder of the first year of operation. Upon completion of the first year of operation, the KDHE will evaluate the efficiency of the treatment system and adjust operating procedures as necessary.