VMS Filter Sock - the Environmentally-conscious vault maintenance system
The VMS FILTER SOCK is a revolutionary, environmentally-conscious filtration system designed specifically to remove the oil and sediment typically found in underground utility vault waters. As such, the VMS FILTER SOCK is the optimal solution for the dewatering of utility vaults and benefits companies in the electric, natural gas and water distribution industries, telecommunications companies, pipeline and other companies, who utilize and maintain underground vaults.
Utility vaults can be a collection point for waters from storm water inflow, subsurface infiltration, and/or leakage from nearby utilities such as storm sewers or sanitary sewers. Water that has entered the vaults and remained there for an extended period of time may contain a wide array of contaminants that cannot be discharged to a storm drain or other surface water. Potential contaminants include oil and grease that can leak from equipment or rust and sediment from storm water infiltration. The VMS FILTER SOCK system provides a simple method for the efficient and environmentally-conscious removal of vault waters and disposal of such contaminants.
Utilizing patented oil/sediment filtration materials, the VMS FILTER SOCK is manufactured in a four-layer design to filter suspended solids (as fine as rust) and to remove oil from moderately contaminated vault waters.
- Layer 1: The inner layer is made of a lipophilic (to attract oily organic compounds), hydrophobic polymatrix filter blend. This layer of fabric can absorb up to ten times its weight in hydrocarbons, or about four gallons of mineral oil per sock.
- Layers 2 & 3: The second and third layers are co-polymer blends that filter particulate matter. The second layer retains the larger sediment particles and the third layer retains submicron-sized particles. These layers are designed to allow high pumping rates while filtering small particles.
- Layer 4: The final outer layer is made of the same fabric as the inner layer, and provides a final polishing step before the water is discharged to the storm drain system.
The VMS FILTER SOCK measures 7.5"x66", and is sewn closed on all sides to ensure that all contaminated water passes through the VMS FILTER SOCK prior to release to the storm drain system. Fabricated with a reusable, quick connect fitting (to minimize contact with vault water residue), the VMS FILTER SOCK easily connects to any hose assembly and is furnished in a liquid-tight container to protect the sock prior to use and to contain any liquid runoff after use and prior to disposal. The VMS Filter Sock can withstand pumping rates of 150 GPM, however a maximum pumping pressure of 10 psi using a centrifugal pump is recommended.
Advantages of the VMS Filter Sock
- Ease of use by field crew personnel
- Low cost compared to vacuum truck dewatering methods
- Time-saving, enabling increased productivity and enhanced planning
- Environmentally-conscious, preventing contamination of storm drain waters
- Regulatory compliance
- Enhanced public image
VMS Filter Sock products
The VMS FILTER SOCK ensures sound environmental and economical practices in dewatering utility vaults and should be included as part of an overall Best Management Practices system.
The recommended method for using the VMS FILTER SOCK is as follows:
- After opening the vault and visually determining that water is present, field crew personnel collect a vault water sample using a bailer. The water sample is visually inspected for turbidity, sediment and oil sheen. The illustration below shows a succession of water samples that may be encountered.
- The VMS FILTER SOCK is used for vault dewatering where the water sample appears similar to the illustration samples represented in the green and yellow zones. Where the water sample is excessively rusty, cloudy, or has significant oil sheen or sediment accumulation, or appears as any of the illustration samples represented in the red zone, we recommend that dewatering be performed by vacuum truck. (Note: The VMS FILTER SOCK can be successfully used where these excess conditions are present as absorption, filtering and polishing capabilities remain, however additional socks may be required.)
- Upon determination that the VMS FILTER SOCK will be used for vault dewatering, connect the VMS FILTER SOCK to the pump hose, using the quick connect fitting, and place the VMS FILTER SOCK flat on the ground as close to the storm drain inlet as possible. (Prior to set-up, pumping system components should be inspected to ensure proper operation and absence of leaks.)
- Utilizing a centrifugal pump with a discharge pressure not exceeding 10 psi, place the pump intake below the surface of the water (and above any accumulated sediment), and begin pumping. The pumping operation should be monitored for signs of oil sheen and/or low flow. If either of these conditions exists, the VMS FILTER SOCK is filled to capacity and should be replaced.
- Upon completion of the pumping operation, disconnect the hose from the pump and roll the hose toward the VMS FILTER SOCK to force water remaining in the hose through the sock. Disconnect the VMS FILTER SOCK from the hose and allow residual water to drain through the sock. Then roll the VMS FILTER SOCK and place it in the liquid-tight container that the sock was delivered in, sealing the lid. The VMS FILTER SOCK and container can be disposed of as non-hazardous waste.