The Power Engineering Company of Denver, Colorado (PEC) retained ERO Resources Corporation to determine the extent of chromium contamination in ground water and soil beneath and adjacent to their industrial plating facility. ERO employed several innovative techniques, such as Direct Push methods coupled with field analyses for hexavalent chromium, to cost-effectively track the chromium plume in the ground water. Also, ERO used slant hole drilling to characterize the soil beneath the plant in areas that would otherwise be inaccessible.

In addition to site characterization, ERO developed a method to create a “geochemical barrier” to prevent offsite migration of dissolved hexavalent chromium. The barrier has resulted in significantly lower downgradient chromium concentrations and currently meets compliance standards. ERO has also developed techniques for the in-situ treatment of highly contaminated soils beneath and adjacent to the PEC building. A pilot test of this technique successfully treated soils from the surface to the water table. The process is currently being used for full-scale source area remediation.

ERO has provided environmental services to the General Services Administration (GSA) for the Denver Federal Center (DFC) since 2001. Since the 1940s, potentially hazardous activities have occurred at the DFC including the production of munitions, laboratory testing of pesticides and herbicides, animal testing, and testing of various roadway materials. The GSA is currently investigating and characterizing the entire DFC under the Resource Conservation and Recovery Act (RCRA) program administered by the Colorado Department of Public Health and Environment.

ERO performed the following services for GSA:

• Developed, implemented and completed RCRA Facility Investigation (RFI) workplans for specific investigation areas at the DFC
• Performed historical reviews of building utilities, space usage, and documents to develop cost effective investigation plans to assess areas for potentially hazardous materials
• Installed permanent ground water monitoring wells, sampled soil and water around specific features, and located and sampled structures and features such as sumps, tanks, seeps, and outfalls for potentially hazardous materials
• Removed sumps and abandoned a tank used by the Denver Ordnance Plant
• Developed Standard Operating Procedures for air sampling of interior spaces and low flow groundwater sampling

The Prairie Waters Project is the City of Aurora’s near-term plan for a new water supply source for the City. The proposed scheme includes a 34-mile pipeline, a new water purification plant, and a water campus. ERO assisted the City and the engineering team with addressing environmental issues for the proposed project.

ERO completed numerous Phase I and Phase II site investigations on agricultural properties and proposed rights-of-way for either acquisition or easement alignment. Site investigations were conducted on flexible schedules to accommodate varying property access and real estate transactions, and were completed in a timely manner so as not to delay design progress. All investigations were completed to comply with the ASTM Phase I and Phase II standards and guidelines.

ERO Resources has assisted several nationally recognized private homebuilders with development activities at the former Stapleton International Airport site, the largest infill project in the United States. As part of various due diligence efforts, ERO performed more than a dozen Phase I Environmental Site Assessments and several Phase II Site Investigations within the former airport site, now known simply as Stapleton. The new homebuilders’ locations straddle former runways, maintenance hangars, and taxiways, as well as undeveloped “back-lot” portions of the former airport. Land parcels range in size from single lots to multiple blocks within several different subdivision filings.

During the Phase I ASTM E-1527 process, ERO reviewed historical data and voluminous environmental records to assess historical airport operations and remediation efforts which would affect our clients’ proposed residential development plans. Based on the reviews, site reconnaissance, and interviews, ERO provided professional opinions regarding the environmental conditions on our clients’ parcels, and made substantive recommendations to minimize their environmental liability.