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CDS units capture diesel spilled over a California business site

Ontario Mills - Ontario,

Stormwater Treatment


Ontario Mills



Technical Description:

(4) CDS Hydrodynamic Separators

The Ontario Mills and Vintage by the City Mall located in Ontario, Calif., uses four CDS continuous deflective separation units, a swale and a retention basin to manage storm water on site. A diesel truck entering the loading dock area accidentally punctured one of its saddlebag fuel tanks. The truck entered the site at the north end and traveled south through the site, spilling approximately 75 gal of diesel fuel along its course.

Fuel poured out along the pavement, which drains to a catch basin and then through a CDS system before discharging to a retention pond. The Ontario Fire Department was quickly called after the spill, and their response crews were able to recover about 5 to 10 gal on site shortly after arriving. However, the fire department could not determine where the bulk of the spilled material had gone other than to a downstream storm drain.

The department called in Filter Recycling, a leader in recycling of liquid and solid waste, to locate the spilled material and perform cleanup procedures for them. Filter Recycling ended up contacting the city’s engineering department that day to get help locating the plans for the onsite storm drain system.

The response team inspected the retention basin downstream and found no odor or other trace of the spill. But before they left the site, the team called Ontario Storm Water Program Manager Steve Wilson, who pulled up the storm water drainage plan for the site. Wilson saw the CDS system on the plans and walked them through locating and cleaning it.

The cleanup crew found the manhole and discovered the missing diesel fuel floating in the sump of the CDS unit, nicely contained upstream of the oil removal baffle. Approximately 75 gal of spilled fuel was easily suctioned out of the CDS unit immediately afterward—that is 75 gal of diesel that was prevented from entering the downstream basin.

“If the CDS system had not been there, the cleanup would have gone from a few hours and near- complete recovery to a much more difficult remediation effort with probable risk of groundwater and soil contamination” Wilson said.

Due to the Contech CDS system in place on site, the diesel spill went from being a disastrous cleanup to a manageable situation.


Technical Description:

(4) CDS Hydrodynamic Separators


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