Redevelopment activities include excavation of the entire Site footprint to depths of 26 to 32 feet bgs. Heavy metal and TPH-impacted soil will be excavated under the observation of the General Contractor across the Site prior to completing the additional excavation of underlying clean, native soils.

All soil management and handling activities will be conducted in accordance with applicable federal, state and local regulations. During the implementation of the project, other data may be collected for profiling purposes and to further refine the quantities and classification of potential waste materials that may be generated.

Excavation of Heavy Metal and TPH-Contaminated Soil

Heavy metal and TPH-impacted soil is going to be fully excavated, removed and transported to an appropriately licensed facility. Excavation of impacted soil will be conducted in the following sequence:

  • Develop staging areas, access paths for equipment, work zones and decontamination areas for use during handling of contaminated soil to reduce the potential of tracking waste off-Site;
  • Identify locations of perimeter air monitoring stations, as necessary, and begin monitoring to comply with BAAQMD regulations, the HASP, and the protocols in Section 10 of this SGMP;
  • Stockpile soil for characterization or direct load onto trucks for appropriate off-Site disposal.
  • Soil samples representative of the volume to be transported off-site will be collected in-situ and/or from stockpiles and characterized using an analytical program developed in consideration of off-site disposal facility or third party acceptance requirements, and the ACDEH LOP Soil Import/Export Characterization Requirements. The soil to be off-hauled will be accepted by the disposal facility or third party prior to being removed from the Site.

Contingency Measures for Previously Unidentified Suspect Soils

The following contingency measures will be implemented in the event that previously unidentified suspected chemically-affected soil is identified during Site excavation. All contingency measures will be conducted by HAZWOPER-trained environmental professionals in accordance with the HASP.

Additionally, the Environmental Consultant will be on-call during excavation and at the Site in the event of unexpected contamination or subsurface structures are encountered.

Identification of Contaminated Soil

During grading and excavation activities, potentially contaminated soil may be identified via observation of any of the following characteristics:

  • Presence of free product. Free product is defied as a petroleum product (e.g., oil) or chemical in its natural state, un-mixed with water. Free product is often identifiable by the presence of an oily substance or the presence of any oily sheen on soil or water.
  • Oily or other staining. oily staining is not consistent in appearance but often has a black dark gray, dark brown, or greenish hue. Other unusual staining or soil discoloration (e.g. blue soils) should also be considered potential evidence of contamination.
  • Petroleum or Chemical Odor. Any petroleum or other chemical odor should be noted regardless of whether a visible sign of oil or staining is encountered. If odorous soil or debris is encountered, the material may be contaminated and should be evaluated as soon as possible by field screening with a photoionization detector (PID) and, if warranted based on the field screening results, sampling for laboratory analysis. Areas exhibiting elevated PID readings above health and safety action levels should not be entered until laboratory data is available to evaluate potential health risks.
  • Presence of Elevated Metals. Elevated metals in soil may be identified by strong and sometimes bright discoloration. Any chemical or metal odor should be noted regardless of whether a visible sign of elevated metals is encountered.
  • Presence of Waste Debris. If debris such as concrete, scrap metal, bricks or other garbage is identified, the debris and surrounding soil may be contaminated.
  • Contractor will inspect the integrity of concrete pads, building foundation floors, piping, or other subsurface structures as they are removed, and look for visual and/or olfactory evidence of a release in soil. If visual and/or olfactory evidence of a release in soil is observed, the contractor will notify the Environmental Professional. Our contractor will monitor area around construction Site for fugitive vapor emissions with appropriate field screening instrumentation, including use of a PID to screen for VOC’s.

If soil is exhibiting evidence of contamination is encountered during excavation, the Contractor will cease excavation activities in the area and notify the Environmental consultant within-in 24 hours. The Contractor will not conduct any work in the area of concern or replace nay known or suspected contaminated soil in the excavation without prior approval by the ACDHE LOP.