Site Restoration – Ohio National Guard – Blue Ash, Ohio

It seemed like a normal removal & closure of a “Leachfield” and Septic Tank followed by a site restoration at the Air National Guard Station location in Blue Ash (Hamilton County), Ohio. This work was proposed to be performed by CBC Engineers & Associates, Ltd. in August of 2004. The work was to be performed in accordance with specified Ohio EPA, Ohio Health Department and Ohio Air National Guard requirements. All contaminated soil and Septic Tank system was to be removed and the site restored using imported quality soils to replace the poor soil hauled away. However, more was revealed when the contaminated soil was hauled away.

Project summary

Work actually started by CBC Engineers & Associates, Ltd. on this project in the fall of 2003 overseeing the removal and disposal of wastewater and sludge from the “inactive”, underground Septic Tank and Siphon Tank system. This original “cleanup” activity included CBC environmental personnel to coordinated and document the removal and disposal of approximately 6,600 gallons of wastewater and sludge from the “inactive”, underground Septic Tank and Siphon Tanks. Both tanks were also then steam-cleaned with a “high-pressure” wash to remove and residual slurry and or/sludge material from the system. This work was completed and documented on the dates between September 30th to October 1, 2003.

Further site cleanup was to take place to take place to remove the “leachfields” that were original connected to the Septic and Siphon Tanks. CBC responsibilities were to include the removal on the leachfields and tanks and any contaminated soils. These materials were to be transported and disposed of by an accredited landfill. And CBC was to be on site to observe and take samples of all materials removed and have several tests run for compounds such as volatile organic compounds (VOC’s), total petroleum hydrocarbons (THP) and soil pH to name a few. The removed contaminated soil was then to be replaced with a 310 gravel base with a < 6% organic “topsoil” cap approximately 2 feet thick. It was was estimated that approximately 2,100 cubic yards of contaminated soil was to be removed and replaced. This work was started in early 2005. 

Two (2) is Company – Three (3) is a crowd

During the excavation of “leachfield” number one (1), CBC field personnel discovered yet a third “leachfield” system below buried below at a depth of eight (8) feet below grade. The existence of this third “leachfield” was unknown to the Ohio Air National Guard officials and was not identified in any layout maps, system diagrams or specifications provided to CBC prior to providing the scope of work to be performed. Obviously this posed a change in the required amount of removal, disposal and replacement of contaminated soils. CBC Engineers & Associates, Ltd. worked hard with the Ohio Air National Guard to negotiate a change order that was fair and cost effective. The size of this third system was approximately as large as the combination of the first two. The total of contaminated soil to be removed, disposed, and then replaced had gone from 2,100 cubic yards of material to approximately 4,100 cubic yards of material, however, CBC’s contract did not double as we did our best to help mitigate this unexpected cost to our Client. All the contaminated soil was removed, disposed of and replaced per the amended quantities and was complete by August of 2005 when CBC personnel submitted the final report. This was to help the Ohio Air National Guard prepare for a base closure at this site and prepare the land to be sold.