Category Archive

We’ve seen it all: sand, grit, sludge, lime buildup, vegetation, and even larger debris such as metal handrails and lawn chairs limiting capacity in pipes and tanks. U.S. Submergent Technologies can remove any type of material (yes, even lawn chairs!) from wet or dry environments in a variety of structures. We use the extremely versatile Combination3® Truck to specialize in removing material from structures such as pipes, tanks, and lift stations while they remain in full operation, and we can also perform work in a drain-down or bypass situation when larger debris is present. A history of removing difficult material from pipes, tanks, and other structures U.S. Submergent Technologies has tackled unique situations, including heavy lime accumulation in a large biological treatment unit, resulting in the removal of 60-tons of lime, sand and grit. We’ve successfully cleaned a tank overrun with 4-foot high vegetation sitting on an 8-foot root system. The U.S. Submergent Technologies’ crew once developed a crane attachment to be used with the Combination3® Truck’s extendable boom to reach and remove difficult rag material — and even a metal handrail — from a splitter box.  Our experienced crew removed wood and lawn chairs from a stormwater box culvert, as … Read More

PREVIOUSLY UNREMOVABLE MATERIAL REMOVED IN EAST FLORIDA Sand, grit, lime, rags, sludge, and other wastewater residuals had accumulated over time in two large East Florida BTU structures, reducing the wastewater treatment plant’s overall capacity. Due to the challenging nature of the material, previous companies had been unable to clean the structure. A buildup of lime sludge was the main issue the facility was facing, and the material was described as having the consistency of “slightly dried out play-doh.” The cost of Sand, grit, lime, rag, and  sludge buildup for wastewater treatment plants A buildup of material in a tank such as this has the potential to cause several issues, including reduced treatment capacity and wear and tear on equipment.  A drain-down and confined space entry was necessary in order to efficiently access the material.  Each of the facility’s above-ground BTU tanks measured at 113-feet by 130-feet, with 17-foot high walls. The Combination3® Truck’s powerful vacuum was used to remove sand, grit, lime, sludge, and rags without any issues.  USST’s vacuum delivers nearly double the CFM of a standard vacuum truck, allowing the crew to remove large amounts of wastewater residuals and complete the job quickly and on schedule.  In total, … Read More

WHAT MAKES IT DIFFERENT? In a word, Gravity! The Combination3® Truck is a unique, ambidextrous tool that allows us to clean pipes, tanks, and a variety of other structures while in operation. It can vacuum using suction and pump using positive pressure, as well as perform jetting. Here, we’re going to examine the differences between traditional technology versus the powerful capabilities of the Combination3® Truck. Let’s take a look at how traditional vacuum technology works Vacuum technology has been around for 50-years and is typically the first tool called upon for cleaning most pipes and tanks. A vacuum uses the flow of air to move debris into the debris box.  In a dry environment, this approach works well. Vacuum technology begins to be less effective with the presence of water. As the amount of water increases, the effectiveness of removing debris such as sand and grit becomes less effective. This is because water is lighter than the debris to be removed. As a result of this natural consequence of gravity, the debris box fills with water. Essentially, the vacuum moves the lighter material first. This is especially true for large diameter pipes. As pipe diameter increases, the flow of water … Read More

NITROGEN PURGE PERFORMED ON TANK TO LOWER EXPLOSION HAZARD PRIOR TO CLEANING Sludge and other wastewater residuals had accumulated over time in a Southeast Florida digestor, reducing its treatment capacity. Measuring 65-feet in diameter with 36-feet high walls, the tank was in need of cleaning which contained levels of methane due to the treatment process. Methane buildup in wastewater tanks requires additional safety protocols Methane buildup in wastewater tanks occurs naturally due to the treatment process and has the potential to be hazardous. A drain down of the digestor was necessary before work could commence. To create a safer environment for crew members and reduce the risk, a nitrogen purge was performed to displace the methane found in the tank. Because confined space entry was needed to access and remove material, USST crew took extra care to monitor air quality levels, maintain proper ventilation, and check gas meters. “We take care to follow all safety and compliance procedures when entering a confined space,” said Charles Harrington, USST Foreman. “We got in there safely and were able to remove large amounts of material quickly.” How U.S. Submergent Technologies removed 360 tons of sludge from a covered digester The Combination3® Truck’s powerful … Read More

NO DRAIN DOWN REQUIRED TO CLEAN OUT YEARS OF BUILT UP MATERIAL IN CENTRAL FLORIDA WASTEWATER FACILITY An oxidation ditch at a Central Florida Wastewater Treatment Plant was in need of cleaning, having built up a significant amount of sand and grit.  The facility’s treatment process is comprised of a Type 1 Oxidation Ditch operating as a conventional activated sludge treatment facility measuring 320-feet by 70-feet. How U.S. Submergent Technologies removed sand and grit from the tank without performing a drain down USST Foreman, Michael Kisling, led the USST crew through the project from start to finish, utilizing the powerful Combination3® Truck and GritGone Process® to tackle the job. The truck’s extended boom and downhole pump were used to reach and remove sand and grit from the tank without having to perform a drain down. “One of the advantages of our equipment that makes it so unique is that we can remove very large amounts of material while the whole facility remains in operation,” said Michael. “Plants don’t have to shut down or alter treatment flow, and we can reach and remove material quickly.” Another advantage of using the Combination3® Truck to perform the cleaning is that confined space entry … Read More

WHY EVERY CITY & COUNTY UTILITY SHOULD BE CONCERNED ABOUT THEIR COLLECTION SYSTEM & THE CHALLENGES OF CLEANING LARGE-DIAMETER PIPE Water and wastewater collection and treatment processes are largely out of sight, out of mind. Our society often takes this infrastructure for granted and is largely unaware of what’s happening below their feet, even though every person in this country uses it every day at home or at work. Large-diameter pipe (LDP) is generally treated the same way throughout our industry; we don’t see it regularly, so we assume it is functioning properly. LDP infrastructure is primarily only cleaned or rehabilitated when issues arise, such as overflows or collapse that force attention. Once an emergency situation arises, utilities typically scramble to solve a large and complicated issue that they are unprepared to handle, exacerbated by the fact that large-diameter pipe is difficult to clean under flow while in service. Managing Flow in Large vs Small Diameter Pipe Large-diameter pipe is generally described as 24-inches in diameter or larger. Typically, utility systems have regular maintenance plans for smaller pipe systems 18-inches or smaller that involve a vacuum-only approach. Because of the smaller size of the pipes, cleaning this infrastructure is routine … Read More

39-TONS SAND AND GRIT REMOVAL PERFORMED ON DIGESTER Cleaning sand and grit from a digester at a wastewater treatment plant A digester at a Central Florida Wastewater Treatment Plant was due for cleaning, having built up an accumulation of sand and grit. The structure was cleaned in operation with the aid of funding from Florida’s Sand & Grit Grant Assistance Program. See if your facility is eligible for similar funding by reading more about the program here . Measuring 100-feet in diameter with approximately 18-feet high tank walls, the digester was cleaned using the versatile Combination3® Truck. Due to the size of the facility, the structure had to be cleaned while remaining in full operation. No bypass or shut down was necessary to remove the material and no confined space entry was required to complete the job due to the adaptive technology of USST’s equipment and skill of the crew members. Led by USST Foreman Charles Harrington, the crew utilized the Combination3® Truck’s extended boom and downhole pump to remove sand and grit while navigating around coarse air diffusers found on the bottom of the tank. “This kind of precision cleaning is difficult to accomplish while a structure remains in … Read More

As you may or may not be aware, Florida has funding available through a grant assistance program for qualifying utilities to remove sand and grit from their facilities. We’ve got answers to some of the most frequently asked questions about the Sand & Grit Grant Program below. When did the program start? The program began in 2014 and is administered by the Florida Department of Environmental Protection (FDEP) developed to assist wastewater treatment plants in the removal of sand and grit to increase capacity, reduce energy use, and improve effluent quality. How do I qualify? Your facility must be a public utility with an average annual daily flow of 3MGD or under, and a portion of the plant must remain online during removal. What is the process? A simple, 1-page information sheet must be filled out; once it has been submitted to the FDEP, they begin to draft the grant agreement. How much funding can I receive? If eligible, your facility will be reimbursed 50-100%. There is no limit to the amount of funding your facility can receive through the grant program. How many structures can I get funding for? As many as needed that qualify. There is no limitation to the … Read More

300-FEET OF BLOCKAGES REMOVED INCLUDING WOOD, LAWN CHAIRS, YARD DEBRIS & MORE After experiencing a series of overflows in a residential area, a West Florida city was looking to clean up a severely blocked stormwater box culvert.  Due to a fluctuating tide schedule creating a surcharged environment, the stormwater structure was cleaned in both wet (high tide) and dry (low tide) conditions. Paul Stephenson, one of USST’s experienced Foremen (read more about Paul here!), led the USST crew on the project, cleaning more than 300-feet.  “Having our Combination3® Truck allowed us to get everything done in one go,” said Paul. “We used a number of setups to remove material with one truck, including the vacuum, downhole pump and jetter, depending on whether the tide was in or out and the resulting conditions in the structure.” The USST crew utilized the downhole pump and jetter when water was present in the structure to remove sand and grit and switched to vacuum to remove remaining material during dry conditions. In total, 12-yards were removed and disposed of at an offsite city facility.  Lawn chairs, wood, and yard waste were some of the larger debris removed from the structure. There was minimal intrusion … Read More

MASSIVE BUILDUP OF RAGS, DEBRIS, AND EVEN METAL HANDRAILS FROM TWO STRUCTURES Access issues had prevented two splitter box structures at a South Florida wastewater treatment facility from being thoroughly cleaned in years.  A large amount of accumulated rag material had built up over time, and the structure was experiencing significantly reduced capacity. The two structures in question consisted of an Auxiliary Secondary Clarifier Distribution Chamber with dimensions estimated at 30-feet by 45-feet as well as a Secondary Clarifier Distribution Chamber measuring approximately 40-feet by 40-feet.  These two structures function as splitter boxes for a secondary clarifier at the facility and serve to split flow from the clarifiers to oxidation tanks. “A drain down was necessary to evaluate and perform maintenance on the structures,” said Michael Kisling, USST Foreman on the project, “but once the water level was lowered, it was clear that the estimated 6-to-8 feet of rag and debris material was going to be difficult to remove.” The top level of the structures had been cleaned over the years, but rag material had built up due to the depth and position of the debris.  The USST crew developed a crane attachment to be used with the Combination3® Truck’s … Read More