In the world of hazardous waste, there are many ways to haul and store your waste. Some of the equipment used to accomplish this includes above- and below-ground storage tanks, tanker trucks, and more. The storage capacity of these pieces of equipment can vary, for example, storage tank volumes can range from 2,000 gallons to well over 30,000 gallons. Tanks like these can regularly be seen throughout local highways, containing hazardous and non-hazardous materials. However, regardless of their contents, most equipments used to haul and store waste must be decontaminated if it is to be continuously used.

A common example of equipment that requires routine cleaning is a tanker truck. Tankers can carry liquids, such as water, acids, peroxides, and solvents, to name a few. Even if the contents of the tanker are not particularly aggressive, prolonged contact with the tank surface could ultimately damage the tanker. This makes it understandable as to why tankers must be regularly “washed out.” When it comes to hazardous and non-hazardous substances, preventing residuals from staying in the tank and potentially mixing with the next waste stream being transported is extremely important. Generally, these types of washouts are done using pressure washers at a treatment or disposal facility in a matter of minutes. By performing a washout, the tanker is ready to perform its next job.

Cleaning tankers is a fairly simple procedure, although the same cannot be said for storage tanks. Because storage tanks can be above or below ground, and while they usually contain between 3,000 to 5,000 gallons, they can hold upwards of 100,000 gallons based on their purpose, resulting in potential hazards to the technician performing the decontamination and cleaning.

 

So, what makes storage tanks more dangerous to clean?

When a storage tank needs to be cleaned, a worker must enter the tank to ensure proper decontamination. Additionally, storage tanks generally contain only one opening for entrance and egress, which increases the risks and concerns that may endanger the technician. Because of this limited space and other features of storage tanks, storage tank cleanings are categorized as a confined space.

The definition of a confined space is “a space that is large enough to enter and perform work, not designed for human occupancy, with limited openings for entry and exit.” (To learn more specific details about confined spaces, refer to our Basics of Confined Space). The hazards afforded by tanks and tank decontamination services are many, including dangers from toxic vapor and gas releases, explosions, radiation, oxygen deficiency, and physical hazards. Therefore, specific training and certifications are necessary. While performing any sort of storage tank cleaning, it is essential to have the following Personal Protective Equipment (PPE) as recommended by OSHA)[1]:

  • Hard hat for overhead impact or electrical hazards
  • Eye protection with side shields
  • Gloves chose for job hazards expected (e.g., heavy-duty leather work gloves for handling debris with sharp edges and/or chemical protective gloves appropriate for chemicals potentially contacted)
  • ANSI-approved protective footwear
  • Respiratory protection as necessary—N, R, or P95, filtering facepieces may be used for nuisance dust (e.g., dried mud, dirt and silt) and mold (except mold remediation). Filters with a charcoal layer may be used for odors.

*These are the most basic necessities for a confined space entrant. Additional PPE is required based on all hazards that are present.

 

Are there any varying confined space entry & rescue requirements between CAL OSHA & Federal OSHA?

Many of the practices between Cal/OSHA and Fed OSHA are quite similar; a majority of the differences come down to specific permissible levels for some air contaminants, the implementation of an IIPP (Injury Illness Prevention Program, which still applies to workers during a confined space jobs), better ergonomic practices, and a more stringent Heat Illness Prevention Program among a few others for overall entry.

As far as rescue is concerned, the standards for Cal/OSHA and Fed OSHA are nearly identical. Here is a list of some of the things that are required by both Cal and Fed OSHA:

  • Confined spaces must be clear of unauthorized individuals
  • All on-site rescue procedures must include either non-entry rescue or other means of rescue services
  • An entry supervisor must ensure that rescue services are available and that the means for summoning additional services (fire, medical, etc.) are operable
  • All entrants, attendees, supervisors, and rescue personnel must be properly trained
  • At least one member of a confined space team must be trained for rescue
  • At least one member of a rescue team must be CPR certified
  • Once every 12 months, all members of a rescue team must practice by simulating rescues in conditions similar to those of each confined space that they will be expected to provide rescue services
  • Non-Entry means of rescue are allowed, such as the tripods, retractable winch, and harnesses that our technicians use, so long as the equipment used is attached to mechanical devices or anchor point outside of the space and does not increase the overall risk of entry or would not contribute to the rescue of an entrant

When considering proper PPE for tank cleanings or decontaminations, it is vital to remember not only the inherent safety hazards but also the managerial requirements and possible workplace stressors involved (psychological, physiological, environmental, etc.) as well. For example, numerous safety hazards include restricted vision and movement while working inside tankers, as well as difficulties communicating with others while wearing air respirators. These concerns will be addressed in your confined space permit when required.

 

Tips for safety while preparing tank cleanings (CHOP)

  1. Create a solid plan – To reduce the risks involved with tank cleanings, coordinate a plan with plant managers and/or trained personnel to assess and plan for possible stressors involved. Creating a solid plan also involves attaining any necessary permits to enter the confined space, and coordinating safety meetings to ensure personnel is aware of any possible risks involved.
  2. Have a Confined Space Emergency Rescue Team – It is required by California Law that confined space services must have a trained Emergency Rescue Team on standby. Even if your plan is executed perfectly, unpredictable things could happen. It is best to over-prepare than to react to a situation.
  3. Only use trained and certified personnel – Again, to reduce hazards involved with tank cleanings, only use professionals who are trained and have the industry-specific knowledge and experience to carry out a safe tank cleaning. Any person who has questionable health or lacks knowledge should not be involved.
  4. Practice safety at all times – Whenever performing any type of tank cleaning, proper PPE must be worn throughout the process. Additionally, personnel must use the proper safety equipment, like oxygen and gas detectors and emergency medical kits, to be properly prepared for any emergency that may come about. Appropriate safety procedures, like properly shutting off any valves, should also always be accounted for while performing tank cleanings.

When used for hazardous waste, tanks must be in full compliance of regulations set forth by the EPA and DTSC. If a tank is not in compliance, the end results could be hazardous to the planet and your employees. Additionally, following proper safety procedures is critical throughout this process. Because of the extensive training and hazards involved, hiring experts might be the best way for your company to properly clean a hazardous waste storage tank.

HTS Environmental Services is available for a variety of services, including hazardous waste disposal, tank cleanings, and more. If you have any questions related to confined space or require trained personnel, please feel free to contact us.


[1] Entry into Confined Spaces. OSHA. https://www.osha.gov/SLTC/etools/hurricane/confined-spaces.html