If you live near a landfill, this is a scenario you should be concerned about:
·The landfill began accepting waste before 1990.
·Groundwater in your area flows from the landfill in the direction of your home.
·The groundwater is your home’s water supply and/or the groundwater is very shallow (50 feet, or less, below the ground surface).
If this is your situation, you should be concerned about the possibility that the landfill has contaminated your groundwater.
Landfills constructed before 1990 were often cesspools of politics, incompetence, and, sometimes, corruption. There were few meaningful and strictly-enforced standards. As a result:
·The landfills were often unlined. Today’s landfills, at least theoretically, have liners at their very bottoms that are comprised of two feet or more of clay, overlaid with a plastic or other covering, all of which is designed to prevent (or at least significantly slow) the flow of landfill contaminants into the groundwater below. Before 1990, however, landfills often had incomplete liners, or no liners at all. This was due to many factors, including that politically-powerful landfill operators persuaded politicians that liners were an unnecessary expense, and the state and local environmental regulators lacked any knowledge of the terrible consequences of unlined landfills. As a result, waste dumped into a 50 foot deep, pre-1990 landfill was often being dumped directly into the groundwater, or just a few feet above it. Think of it this way: when a factory spilled chemicals onto the ground outside the plant in 1980, it might take those chemicals 20 years to sink through the soil and contaminate the groundwater 50 feet below. But when waste was dumped into a 50-foot deep unlined landfill in 1980, the chemicals in that waste contaminated the groundwater within months.
·The landfills often illegally accepted toxic wastes. For the very same reasons of politics, incompetence, and corruption, older landfills that were supposed to accept only household waste, and were forbidden to accept liquid industrial wastes, often accepted the industrial waste anyway. It was cheaper for factories to just send their waste to landfills–even though it was against the law–and, very often, no one was stopping them. So, that waste that was dumped almost directly into the groundwater at the older landfills? Frequently, it included highly toxic industrial waste.
·Older landfills often had inadequate “cover“. Landfill “cover” refers to a thick layer of highly impermeable material that is supposed to blanket the top of a closed landfill, i.e., one no longer accepting waste. The point of the cover was to prevent rainfall from pushing contaminants down through the landfill and ultimately into the groundwater. Restricting the movement of landfill contaminants is a critical requirement for preventing groundwater contamination, but older landfills often neglected adequate post-closure cover.
·The “leachate” collection systems were lousy or didn’t exist. “Leachate” is the ooze that is created at a landfill when landfill waste-including the chemicals in it-mixes with rainwater. Theoretically, this ooze is captured by a network of pipes inside the landfill and directed to a location outside the landfill where it is safely collected and transported to an off-site location licensed to accept the hazardous leachate. But, as with the failed or non-existent liners and cover for the older landfills, leachate collection systems sometimes did not exist at all or were so poorly constructed as to not be effective at all.
·Groundwater monitoring was inadequate. Even the older landfills, technically, were required to install monitoring wells at the landfills’ boundaries, as a means of detecting contamination in groundwater leaving the landfill before it could migrate very far off-site and harm human beings. However, very often the monitoring wells were incapable of providing the intended warnings, because they were placed very far apart, or in the wrong locations, or were tested at the wrong depth (i.e., at a groundwater depth that would not be impacted by landfill contamination). In short, there might in fact be a very serious groundwater contamination problem, but these poorly-located and tested monitoring wells might actually show no problem at all.
The bottom line: older landfills, especially, cannot be trusted to protect the groundwater from contamination. If you want to learn more about a landfill near your home, important information is usually available from your state or local government via your state’s version of the Freedom of Information Act. This information typically includes the landfill’s age, which is the most important thing to know. If it was constructed and began accepting waste before 1990, there is a very good chance that the landfill lacks some or all of the groundwater protections discussed above. Note: beware of any assurances you may see in old records that claim that the landfill is actually lined, has adequate cover, never accepted liquid industrial waste, or has a reliable monitoring well “network”.
For while it is possible that your area’s landfill actually had all of those things, it is just as likely, in my experience, that statements promising that these protections were in place are not, shall we say, 100% accurate.