When it comes to hazardous waste, the government doesn't take anything lightly. In fact, regulations govern everything that happens to hazardous waste from its origin to its disposal. And this process is known as hazardous waste management.
In this blog, we are reviewing the different hazardous waste management systems and the four main hazardous waste treatment methods used today.
The Manifest System
The government uses a cradle-to-grave waste management system, otherwise known as the manifest system
. The root of the manifest system is the actual manifest. This document is used by whoever generated the waste to describe it, as well as the proper way to handle it. Because whoever created the waste is ultimately responsible for disposing of it, the manifest travels with the waste as a description of the contents. Each time the waste changes hands, the manifest must be signed as a proof of record.
Transporting Hazardous Waste
While waste can be transported by ships, trains, and airplanes, it's almost always transported by truck. Truck shipment is the most common because trucks can reach the sometimes difficult-to-find disposal sites. Additionally, within the trucks, hazardous waste is transported using tanks and drums—with exact specifications varying based on the type of waste.
How is Hazardous Waste Managed?
Once hazardous waste reaches its final destination, there are four main approved methods to dispose of it. Although there are recycling and reduction methods available, there will almost always be some waste leftover that will need to be treated or stored.
The four main methods for treating hazardous waste
include treatment, surface storage, landfill storage, and deep-well injection.
Method 1: Hazardous Waste Treatment
The most widely-used hazardous waste disposal method isn't really a type of disposal at all. As the name suggests, waste treatment involves using chemical, physical, thermal, and biological processes to detoxify and remove the dangerous part of the waste or destroy the waste in total.
Chemical treatment methods include ion exchange, precipitation, oxidation and reduction, and neutralization. On the other hand, the most common type of thermal treatment method is incineration. There are special tools used to incinerate hazardous waste and turn it into smaller amounts of solid, liquid, or sludge.
Biological hazardous waste treatment is typically used on waste from the oil and gas industry. And landfarming is the most common biological treatment method. Landfarming involves the use of genetically engineered microbes to stabilize the waste. Of course, even after the waste has been stabilized, crops cannot be safely grown on that land.
Method 2: Surface Storage
Even after waste has been treated
, there will most likely be residue or remaining waste that will still need to be appropriately stored. Surface, or land storage, is the most popular storage solution for residual waste because it's the most affordable and accessible. Unfortunately, even with all the government regulations and precautions, this method can still negatively impact the environment.
Conventional surface storage solutions include waste piles, ponds, and lagoons that are carefully constructed to eliminate the chance of leakage or erosion. Precautions are now used to protect groundwater, but historically these precautions weren't in place, so many older sites are scheduled for cleanup and remediation.
Method 3: Secure Landfills
Secure landfills are mostly used for hazardous waste that hasn't been treated, so there are additional regulations than those for surface storage facilities. Secure landfills are named such because the landfill needs to be at least 10 feet above underlying bedrock or groundwater tables. In addition, secure landfills also need two impermeable liners and a leachate collection system.
On top of all these other precautions, secure landfills need a groundwater monitoring system installed to ensure all other precautionary methods are working. The monitoring system works by regularly sampling and testing the area to catch any leakage.
Method 4: Deep-Well Injection
The fourth method of waste disposal is deep-well injections, which involves injecting liquid waste through steel casings placed in limestone or sandstone. A high-pressure injection is used to ensure the waste is forced into the rock where it is permanently stored. The injection zone needs to be below an impenetrable layer of clay or rock, but it shouldn't be more than half a mile underground. While deep-well injection is relatively inexpensive, because the waste is stored underground, it can pose a risk to the water supply.
Get Trained on Hazardous Waste Management
While we hope this blog post has helped you to answer the question, "How is hazardous waste disposed?" it's not a replacement for official HAZWOPER training
. No matter if you need an 8, 24, or 40 hour HAZWOPER course, we have the training you need. Sign up today!