Other corrections must be made to account for the proportion of throughout the biosphere (reservoir effects).
Additional complications come from the burning of fossil fuels such as coal and oil, and from the above-ground nuclear tests done in the 1950s and 1960s.
Sometimes soil removal, soil blending and chemical injection can all be used to perform a remediation.
As counter intuitive as it may sound, the goal of some remediation projects is not to cleanup a site 100% but rather to reduce contaminant mass and allow natural attenuation to increase. By definition the word remediation refers to the removal or cleaning of a given media that has become contaminated or cleaning of a given media that has become contaminated or impacted with a contaminant or pollutant.
The resulting radiocarbon combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire in a sample from a dead plant or animal such as a piece of wood or a fragment of bone provides information that can be used to calculate when the animal or plant died.
Hydrocarbon contamination from heating oil, diesel fuel and tanks (USTs), that over time leak.
A lesser known but also prevalent form of contaminants are polyaromatic hydrocarbons (PAH).
Contaminants such as petroleum hydrocarbons tend to spread through soil by diffusion and convection over time.
Diffusion is a molecular transport that is driven by differences in concentration.
I is not deliberately produced for any practical purposes.