Opal Group Inc.

Titanium Dioxide Ponds Closure

Confidential Client

Seaford, DE

This 650-acre nylon manufacturing facility was the subject of a RCRA Corrective Action under the Delaware Department of Natural Resources and Environmental Control (DNREC) and EPA Region III. Nineteen Solid Waste Management Units (SWMUs) were identified and investigated. Included in the SWMUs were five process settling ponds containing 12,000 cubic yards of titanium dioxide sludges. The sludges were highly resistant to dewatering by mechanical means (i.e. belt presses and centrifuges) and were similarly unable to be stabilized using convention solidification agents (cement, kiln dust, bentonite, and peanut hulls). Additionally, the sludges contained elevated levels of hydrogen sulfide (H2S). Opal performed testing on the sludges and demonstrated that use of a Super Absorbent Polymer (SAP) was the most cost-effective and technically sound method of solidifying the materials, allowing their truck transport to an approved disposal facility more than five driving hours from the site. The use of the polymer resulted in significant cost savings for disposal since the unit weight of the sludge was not increased as would be the case if conventional solidification agents were employed. Opal was retained to solidify, remove and transport sludges close the impoundments. An associated water treatment plant building, pipe racks and other appurtenant structures were demolished as part of this work.


Services/Descriptions/Materials: Demolition, RCRA, Sludge, Solidification, Titanium Dioxide