FOND DU LAC COUNTY
FOND DU LAC COUNTY
Congressional District # 06
RIPON CITY LANDFILLEPA ID# WID980610190
Last Updated: August, 2010
The Ripon City Landfill site is located on approximately 7.3 acres of land, outside the northwestern city limits of Ripon. The site is located in a rural area, surrounded by woods, a gravel pit, a park, and cropland. Several private homes are located within one-half mile of the site. The site, a former gravel pit, was owned by a private party who leased the land to the Speed Queen Corporation in 1967 for the purpose of landfilling. The city of Ripon began leasing the property in 1968 for the disposal of wastes, and in 1969 was issued a license to operate the landfill. Later, the town of Ripon joined with the city of Ripon in the operation of the landfill. The landfill operated until 1983, accepting municipal, commercial, and industrial solid wastes.
In 1984, a residential well, located 500 feet south of the site, was found to be contaminated with substances from the landfill; this well was abandoned. The landfill area was capped with clay in 1985, vegetation was established, and a gas venting system was placed along the western edge of the landfill. In 1992, a group of potentially responsible parties (PRPs) signed a contract with WDNR to complete a full remedial investigation and feasibility study (RI/FS) and implement a source control remedy.
The city of Ripon had an estimated population of about 7300 people and the town of Ripon had an estimated population of about 1400 people in 2006. Residents of Ripon obtain their drinking water solely from groundwater. One of the city's municipal wells is 3,700 feet southeast of the landfill.
Site ResponsibilityThe site is being addressed through federal, state, and potentially responsible party (PRP) actions.
Threats and ContaminantsThe remedial investigation determined that groundwater beneath and near the site was contaminated with various volatile organic compounds (VOCs), including vinyl chloride, tetrachloroethene, trichloroethene, cis-1,2-dichloroethene, and benzene at low levels. The discovery in 2001 that vinyl chloride was at unacceptable levels in wells at two homes about 1500 ft downgradient (south-southwest) of the landfill has resulted in an on-going investigation of the extent of the contamination. A water line was extended from the city of Ripon to residences that were or could be affected by the expanded groundwater contamination and the State established a "Special Well Casing Pipe Depth Area" downgradient of the landfill, in which new wells are to be constructed or reconstructed to more stringent standards.
Cleanup ProgressA group of PRPs completed the investigation and a study of cleanup options during 1993 and 1994. A Record of Decision (ROD) for the site was signed in March 1996, selecting a new landfill cap, a passive gas venting system, and groundwater monitoring as the remedy for the source control operable unit. The no action alternative was selected as the remedy for the groundwater operable unit since it was believed that groundwater contamination that had migrated from the landfill was not severe enough to warrant active groundwater remedial measures to restore groundwater quality. The PRP group completed construction of the remedy late in 1996. A Preliminary Close Out Report was issued on September 25, 1996. Groundwater monitoring has continued to show changes in groundwater quality with time, with the new landfill cap in place.
A five-year review report was approved by the United States Environmental Protection Agency in May 2001 which concluded that the remedy remained protective of human health and the environment, based on the monitoring results at the time. However, in October 2001, vinyl chloride was detected for the first time in two downgradient private wells at significant concentrations. These two private wells were initially fitted with treatment systems. Later, the residences were connected to the city of Ripon municipal water by means of an extension of the water line to the area. In addition, two other private residences in the same area were connected to the municipal water system.
Semi-annual groundwater monitoring has been instituted for both monitoring wells associated with the landfill and several downgradient private wells. Additional monitoring wells have been installed to help determine the degree and extent of the groundwater plume. As the investigations continue, possible alternative remedies for the groundwater contamination will be considered. An active gas management system at the landfill to replace the passive one is being investigated as an improvement in the source control.
A second five-year review was completed in September 2006. The conclusion was that the remedy, with the additional measures that have been taken, is protective of human health and the environment in the short term. Additional review of the institutional controls is being conducted to ascertain their enforceability and adequacy before the remedy can be deemed protective in the long-term.
ContactsRemedial Project Manager, U.S. EPA
mary tierney (firstname.lastname@example.org)
Community Involvement Coordinator, U.S. EPA
AliasesRIPON LDFL CITY OF
RIPON CITY OF LDFL(HWY FF)