Tale of Testing: Glossary of Terms
Boring (soil boring) – Underground vertical hole created using directional drills and augers for the purpose of determining subsurface characteristics. The number, location, and depth of the soil borings are determined in part by the purpose or goal of the boring investigation. Borings must be completed and sealed (plugged) upon completion following local and state regulations.
Burnsville Sanitary Landfill – A landfill in operation since the early 1960s and originally owned by the Kraemer [Kraemer Quarry] family and known as the Burnsville Landfill. It is currently owned by Waste Management and located less than a mile away from the Freeway Landfill and immediately west of the Kraemer Quarry.
Closed Landfill Program (CLP) – Created by the Minnesota Legislature’s 1994 Landfill Cleanup Act, the Closed Landfill Program (CLP) gives the Minnesota Pollution Control Agency (MPCA) responsibility over up to 114 closed, state-permitted, mixed municipal solid waste landfills to manage risks to the public and the environment. The CLP manages these sites by monitoring environmental impacts and site conditions; determining the risk each landfill poses to public health, safety, and the environment; implementing cleanup actions; maintaining the landfill properties; and managing land issues on the properties.
Closed Landfill Investment Fund (CLIF) – Established by the Minnesota Legislature in 1999, the Closed Landfill Investment Fund (CLIF) is one of the funding sources for the Closed Landfill Program (CLP). The funds are used to pay for the long-term care, monitoring, and cleanup of closed landfills listed under the CLP.
Dewatering – The removal of water from a location through a variety of potential means. For decades, the Kramer Quarry adjacent to the Freeway Landfill and Burnsville Landfill has dewatered the quarry to expose more limestone for mining. This dewatering has lowered the groundwater level in the area surrounding the quarry including both the Freeway and Burnsville Landfills. In essence, there is a large cone-of-depression surrounding the quarry where water flows toward the quarry dewatering sumps. When mining stops and dewatering ends decades from now, it appears likely that some water will continue to be taken from the quarry for the Burnsville and Savage potable supplies. Despite the results of their own study, the Minnesota Pollution Control Agency (MPCA) began incorrectly claiming that once the dewatering of the Kraemer Quarry stops, the flow will reverse and the groundwater will go into the – Minnesota River, requiring treatment prior to entry.
“Dig and Haul” – A “clean-up” method proposed by the Minnesota Legislature that would dig up waste from the Freeway Landfill and haul it to the Burnsville Sanitary Landfill less than a mile away. The estimated cost is $165-$538 million of taxpayer money. This effort could take from six months to two years to complete.
Landfill vs. Dump – A landfill is an engineered and managed facility for the disposal of waste. Landfills are located, designed, operated, and monitored to ensure compliance with state, local and federal regulations to protect human health and the environment. A dump is not officially permitted by regulatory authorities. With the establishment of rules and regulations for landfills in the late 1960s and early 1970s dumps were discontinued.
Eminent Domain – The right of a government or its agent to expropriate private property for public use. Such “taking” must meet the preconditions of, 1) Providing fair compensation to the property owner as required by Minnesota and federal laws and, 2) Articulating a well-defined public use or purpose before the government can act.
Freeway Dump – Located in Burnsville, on the east side of 35W, the Freeway Dump was a separate disposal area comprising nearly 28 acres that operated from 1960 to 1969. The Chalet Golf Driving Range currently sits atop this property. Freeway Dump and Freeway Landfill are two independent distinct properties separated by interstate highway 35W.
Freeway Landfill – Located in Burnsville and bordering the west side of 35W south and the Minnesota River, the landfill property comprises approximately 150 acres. The property also includes a 40-acre quarry on its western side with an ongoing concrete recycling business and a 10-acre Freeway Transfer Station that sorts and moves solid waste for disposal or processing to offsite permitted facilities. Closed and capped in 1990 according to the solid waste rules in effect at the time, Freeway Landfill has been maintained safely and according to state and federal guidelines for its entire existence.
Groundwater – Water that exists underground in saturated zones directly beneath the earth’s surface. It is stored in and moves slowly through geologic materials composed of unconsolidated soil, sand, gravel, clay, and bedrock called aquifers. The area where water fills the aquifer is called the saturated zone. The uppermost surface of the groundwater is the water table. The water table can be located only a foot below the ground’s surface or hundreds of feet down. Groundwater is never completely static as it responds to natural and man-made conditions from precipitation and drought to withdrawal from wells or surface waters for irrigation and drinking water. Groundwater is the source for more than half of the U.S. population; is used to irrigate crops; and is a source of recharge for lakes, rivers, and wetlands, which are formed by groundwater that has risen to the surface. Groundwater discharging to the surface in the Minnesota River valley is the source of the nearby Black Dog Fen and Savage Fen Wetland Complex. Both of these calcareous fens result in groundwater discharges to the surface of the Minnesota River Valley. The use of water from the Kraemer Quarry for drinking water has reduced the need to drill wells that could endanger the fens.
Perched Groundwater – Groundwater occurring in a saturated zone that is above and separated from the main water table by a layer of relatively impermeable material, below which lies an unsaturated zone. The wells the MPCA had installed into the waste at Freeway Landfill have been characterized as ‘perched wells’ by their consultant, indicating the limited water within the waste has minimal downward movement to the lower water table.
Kraemer Mining & Materials, Inc. – Owner of the limestone mining operation adjacent to the Freeway Landfill and the Burnsville Sanitary Landfill. This company began operations in the late 1950s and in 2020 received approval to expand by another 72 acres which will extend operations until at least 2040. To facilitate mining the quarry operates a dewatering system. Since 2009, some water from the quarry has been used by Burnsville and Savage for their potable supply thus eliminating the need for drilling and operating nearby water supply wells that could potentially endanger the nearby calcareous fens..
Landfill Cleanup Agreement – Before landfills are accepted into Minnesota’s Closed Landfill Program (CLP), certain requirements stated in a Landfill Cleanup Agreement, typically executed between landfill owners/operators and the state, must be met. Once these requirements are fulfilled, a Notice of Compliance (NOC) is issued to the owner/operator. The site then enters the program, and the state takes over responsibility for the landfill.
Leachate – Liquid that is generated from water percolating through waste materials, accumulating contaminants. Precipitation that falls on a landfill can percolate through waste and become contaminated with organic and inorganic chemicals, forming leachate. The Freeway Landfill closure plan was completed as required by the regulations in effect at the time and to which a significant amount of additional clean fill material has been placed atop the solid waste in the landfill. The clean fill cap and its green vegetative cover significantly reduce the amount of precipitation and water that can enter the waste, thus minimizing the amount of leachate that can be generated. This has eliminated a significant amount of groundwater infiltration or precipitation infiltration into the waste, in turn reducing the amount of leachate.
Methane – A natural hydrocarbon that is a primary component of natural gas and is produced by decaying organic materials. Considered a greenhouse gas (GHG), methane affects the earth’s temperature and climate system and is emitted from a variety of human-influenced and natural sources. Landfills generate methane as organic materials in mixed municipal solid waste decompose.
Monitoring Well – A solid casing typically metal or plastic, which is drilled, or bored through soil or bedrock into the groundwater below. It is used to obtain samples, monitor groundwater levels, or measure or test groundwater properties. Monitoring wells are sometimes referred to as “observation wells.” The Freeway Landfill has been tested by a series of monitoring wells placed throughout the landfill since the early 1970s without any significant indication of health risk.
PFAS – Per- and poly-fluoroalkyl substances, known as PFAS, are widely used, long-lasting chemicals found in many different consumer, commercial, and industrial products. PFAS enter the environment at sites where they are made, used, disposed of, or spilled throughout their use in general commerce. They can be transported through rainwater run-off or seep into the soil and migrate into groundwater, which can be a source of drinking water. While landfills don’t generate PFAS on their own, they do receive PFAS through the normal everyday waste stream. As such, the Closed Landfill Program (CLP) began testing for PFAS contamination at landfills in 2006. In 2018, the CLP set a goal to sample all CLP sites for PFAS. Currently, PFAS testing has been completed at over 90% of the CLP sites. In addition, the MPCA is currently undertaking a program to sample groundwater at open landfills.
Priority Qualified Facility – A new category created by the Minnesota state legislature for landfills that are listed on both state and federal Superfund lists; are absent a Landfill Cleanup Agreement; include property located within 750 feet of the priority qualified facility, and where the Minnesota Pollution Control Agency (MPCA) has determined that cleanup actions are necessary. As of now, Freeway Landfill is the only state landfill designated as a priority-qualified facility.
Remedial investigation – A process focusing on defining the nature and extent of contamination from a landfill, assessing risk to human health and the environment, and developing a cleanup strategy to eliminate potentially harmful human health and environmental impacts. Both a Remedial Investigation and Supplemental Remedial Investigation were completed for Freeway Landfill in 1988 and 1990 and submitted to the MPCA. The results of both investigations stated that there was no significant risk to human health or the environment requiring remedial action.
Thirty years later, the Minnesota Legislature appropriated $3 million from the Closed Landfill Investment Fund (CLIF) for the Minnesota Pollution Control Agency (MPCA) to conduct remedial investigations – taking samples of closed landfills, including the Freeway Landfill and Freeway Dump, in 2018 and 2019. The MPCA work at the Freeway sites was largely undertaken to support their predetermined goal to dig up the sites as a remedial measure. The sample results were included in a 2019 report submitted to the state of Minnesota. That report recommended further evaluation, but did not conclude the need for any immediate remedial actions because of imminent risk to human health or the environment. As of July 2023, the state has not yet acted on the report.
Source, Pathway, and Receptor Model for Measuring Pollution Risk –A means for measuring pollution risk, including within landfills. The source is the origin of the pollution – anything from vehicle exhaust to a compromised storage container. The pathway is how pollution travels through the environment. And the receptor is who or what can be affected by the pollution – like a river, or a community’s drinking water.
Superfund – A US federal government program designed to fund the cleanup of toxic wastes. Established by Congress in 1980 through the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), the act allocated funds and gave the Environmental Protection Agency (EPA) the authority to identify a process by which owners, working directly with the government, are required to clean-up landfills and other toxic areas designated Superfund sites. Program management may be implemented by the EPA or by individual states through agreement with the EPA – as is the case with Minnesota.
VOCs – Volatile organic compounds (VOCs) are Environmental Protection Agency (EPA)-regulated organic compounds commonly found in groundwater and can migrate into drinking water supplies. All municipal water suppliers are required to monitor water for VOCs and if needed, take action to reduce levels so they are below the Maximum Contaminant Levels (MCLs) set by the EPA. Testing conducted by Freeway Landfill over the past 40 years has only detected two VOCs at extremely low levels and neither were above the EPA-established MCLs.