WITCO Oil Sludge Pits Closure Plan Approval (EPA ID 080018658)
Summary
SCH Number
2001098468
Public Agency
California Department of Toxic Substances Control
(DTSC)
Document Title
WITCO Oil Sludge Pits Closure Plan Approval (EPA ID 080018658)
Document Type
NOE - Notice of Exemption
Received
Posted
9/28/2001
Document Description
Approcal of a Closure Plan that involves minor excavation and a health-risk based closure to industrial standards of previously treated surface impoundment residue. The excavation will be approximately 200 cubic yards of soil containing acidic oil sludge (tar) layers in the soil are approximately 6 inches thick at depths of from 2 to 10 feet below grade. The soil above the tar will be stripped off and segregated. The tar will be visually identified as black asphaltic material and placed in roll-off boxes lined with 6 mm prefabricated polyethylene liner. The roll-off boxes will be transported under manifest to an approved hazardous waste disposal facility. Water sprays will be used to control dust. Air monitoring will also be conducted to assure particulates are controlled. The segregated soil will be replaced and clean fill will be added to bring the excavation to surface grade. The areas will be compacted to 90% of maximum dry density. Air monitoring of the work site and of personnel is required. Workers will be at a minimum Level D personal protection with upgrades to Level C/B depending on air monitoring results. In addition to acidic sludge, polynuclear aromatic hydrocarbons (PAHs) exist in the soils that will not be removed.. The PAHs are located at an average of 12.5 feet to a maximum of 28 feet below grade.
Contact Information
Name
Lisa Austin
Agency Name
Department of Toxic Substances Control, Land Disposal Branch
Contact Types
Lead/Public Agency
Phone
Location
Counties
Kern
Other Location Info
4100 Airport Drive, North of Seventh Standard Road, Oildale Section 35, T28S/R27E; Approximately 4 acres.
Notice of Exemption
Exempt Status
Other
Type, Section or Code
Section 15330 (e)
Reasons for Exemption
The removal of 200 cubic yards of acidic oil sludge (tar) in the soil at the site is a minor action to prevent the release of hazardous waste. The depth to ground water is 400 feet below grade, beneath a clay barrier 300 feet below grade. The Regional Water Quality Control Board determined the clay barrier prevents a pathway of the PAHs to groundwater. The risk assessment approved by DTSC found no increased human health risks to current or future industrial workers at the site assuming that the evacuations proposed occur. Property west and south of the tank farm is undeveloped, although Chevron operated several unlined oil facilities to the south for several years. Commercial property is located north of the tank farm and residential property to the east. The nearest house is approximately one half mile. The nearest school is 1.25 miles to the south. No ecological risks were calculated due to the absence of ecological receptors and no sensitive habitats or cultural resources have been identified in this area which has been subject to previous alteration and industrial uses. The site exists on an active tank farm and a deed restriction between DTSC and the owners will be recorded to restrict the site to industrial use only. This site does not appear on the Hazadous Waste and Substances Sites List dated April 10, 1998.
Disclaimer: The document was originally posted before CEQAnet had the capability to host attachments for the public. To obtain the original attachments for this document, please contact the lead agency at the contact information listed above. You may also contact the OPR via email at state.clearinghouse@opr.ca.gov or via phone at (916) 445-0613.