The Site was characterized using inexpensive FAMs during a single field sampling event, thereby saving costs associated with multiple sampling events. The cost of the incremental investigation using the Triad approach was estimated at $30,000 versus the approximate conventional investigation cost of $400,000 estimated for previous data collection activities at the Site. (The costs to implement the Triad would have been greater if the data from the conventional investigation were not available.) By using principles of the Triad approach, the estimate for remedial action costs were lowered from initial estimates of $14.35 million to $0.76 million, a reduction of 94% of the total costs.

The Navy estimated an analytical savings at $165,000 using the DOE's efficient hexagonal grid sampling system.

Savings for thermal treatment at former NAS Barbers Point versus off site transport and disposal were estimated at $24 million.

More than 44,500 cy of contaminated soil from 82 sites were excavated, treated, and placed back on site as clean fill in less than 2 years.

A consolidated remediation verification report (RVR) for most sites associated with thermal treatment of PCB-contaminated soil and concrete is being developed. The report consolidated information from seven previously prepared RVRs, resulting in time and cost savings to the Navy.

Although no quantitative estimates of cost or time savings have been developed by the project team, there is general concurrence among the stakeholders that the Triad produced a cheaper, faster, and better remedial action than the traditional approach could have. Cost and time benefits were assessed even after accounting for the additional upfront systematic planning, Work Plan preparation, and the DMA that were performed under the Triad. The increased costs and longer remediation timeframes for the traditional approach were projected to include additional mobilizations to the Site with accompanying sampling and analysis plans. Moreover, because the exclusive use of laboratory methods would have produced higher per sample costs, the project team might have had to base remedial decisions on lower data densities under the traditional approach. Lower data densities in combination with laboratory turnaround times could have in turn produced higher disposal costs, given that dirty areas of the Site would have been defined at a lower level of resolution, and that down time or additional mobilizations would have been incurred in waiting for results. The traditional approach would have been more likely to overestimate excavation areas to reduce the risk of an incorrect disposal decision (that is, leaving contaminated material in place).

The work was accomplished with minimal mobilizations, because the necessary quantity and quality of data were collected in each phase. Reduced mobilizations results in less time needed to plan and fund additional phases.

Cost savings are estimated at 40-50% based on the likely need to nearly double the number of sampling points required using a standard grid with no adaptive ability to optimize sampling locations based on near real-time data. The time savings is estimated at 1-2 years based on the need for developing and approving plans for additional field mobilizations and additional time for contracting additional mobilizations.

Cost comparisons were made at the three sites where previous assessments had been performed and multiple data gaps still existed. The three conventional assessments cost $35K, $63K, and $103K. The respective Triad assessments cost $30K (14% savings), $31K (51%savings), and $31K (70% savings). This corresponds to a total savings of $109K for the three sites compared with funds previously spent to assess these sites. This is a less than perfect comparison since the Triad assessments built on the knowledge gained from the conventional assessments. Thus it may not be appropriate to equate the conventional to the Triad assessment costs and obtain a cost savings. However, the incongruity in the comparison is somewhat offset by the fact that the conventional assessments left the investigators with uncertainty regarding the CSM while the Triad assessments tended to remove those uncertainties. For the two sites that did not have previous investigations, the Triad costs were $25K and $32K. In addition, sufficient data were collected at each site to develop CAPs and move the sites out of the investigation phase, where they had been for more than 10 years.

Comparisons of analytical cost savings were not conducted; however, evaluation of fixed laboratory data indicates that soil and water samples were collected at approximately one third of the MIP locations resulting in significant savings and more efficient use of project resources.

Cost and time savings not estimated at this time. However, a primary goal of the project was to use the Triad to increase data density to drive down ultimate removal costs by more effectively isolating and removing those contaminants requiring high cost disposal.

Cost and time savings have not been quantified by the project team. There is consensus on the team, however, that the characterization approach using the ROST^TM in conjunction with other collaborative tools has met the signficant data collection needs for the site much more efficiently and with greater overall accuracy than would be possible with a traditional drilling and sampling program.

The project team estimates that this small project (the soil delineation and excavation program cost only $9,000) yielded approximately $15,000 in cost savings and a minimum of approximately 3 weeks in time savings relative to a traditional phased approach, primarily because the number and length of mobilizations were minimized, and the time between the mobilizations was also minimized.

No formal cost comparison was performed; however, cost avoidance based on system optimization and reduced lag time between data collection and decision-making is expected to be significant.

Cost and time savings were not quantified. However, it is believed the Triad approach helped to reduce the overall project cost by saving time and money in the following ways:

• Real time measurements (coupled with QC procedures to ensure accuracy) allowed the collection of a large data set with high site coverage (that is, high "data density") in a single mobilization.
• Pre-excavation data sets supported a fixed price contract for excavation work based on a high confidence in the underlying contaminated soil volume estimate.
• Rapid data analysis allowed remedial design and remedial action to proceed in a relatively short time period with only limited additional data needs.

In the assessment of the project team, the use of real-time field tools under the Triad approach significantly reduced overall analytical costs and delays by minimizing the number of samples requiring expensive alpha spectroscopy analyses for radionuclides at off-site laboratories.

Based on past experience at Avon Park and other similar installations, the approximate cost of conducting a SI would have been $250,000 per site. Since all four sites included in the initial Triad implementation at Avon Park would have required an RI, the cost per site would have increased by $500,000. The programmatic budget to completely delineate all four sites would have been between $3.1-3.3 million (estimated).

Contractor expenses for the work actually completed now stands at approximately $1.42 million. When government oversight and participation is added in at an estimated rate of 10%, the total cost of the project using the Triad approach is estimated at $1.6 million.Based on above programmatic budget estimate of $3.1 to $3.3 million, the cost of implementing the Triad approach at Avon Park is therefore estimated to have resulted in a 50% reduction in the cost of a SI and RI using more traditional investigative procedures.

In addition to a significant cost savings, the consensus on the project team is that implementation of the Triad approach at Avon Park has advanced progress at the four sites by approximately 3 years. Compressing the SI and RI investigations into one mobilization eliminated a whole phase of data interpretation, document production and review resulting in lower project costs in a shorter timeframe.

No formal cost comparison was performed for the project as a whole because comparative costs for a "traditional" cleanup were difficult to estimate. The project team estimated an analytical cost savings of approximately $5,000. In addition, the Triad approach helped to reduce the overall cleanup cost by saving time and money in the following ways:

• Real time measurements determined when construction was complete. Once FPXRF samples passed the decision criteria, no additional excavation was required in the area, contingent on ICP analysis.
• Increased data densities from the FPXRF refined the cleanup volumes to limit or avoid over-excavation.
• Quicker buyoff on the cleanup was obtained from the regulatory agency upon project completion.

No cost or time savings have been quantified. However, a conventional SI approach, employing more limited judgmental ("worst case") sampling, may have resulted in the Site being unnecessarily designated for the Superfund Remedial program, which would have had significant cost and time implications.

No formal cost comparison was performed. It is estimated that months of time and thousands of dollars were saved.

The incremental cost of the field immunoassay was approximately $24,000, or 16% of the overall investigation cost of $147,000. Cost savings were not the emphasis of this study because 100% of the immunoassay samples were subjected to off-site laboratory analyses in order to generate a collaborative data set. However, the activity demonstrated that the immunoassay in conjunction with site visualization can accelerate nature and extent characterizations for PCBs in sediments. The low relative cost and high data generation rate for the kits further showed how a more accurate CSM can be developed through high data densities and in-field decision-making.

A retrospective analysis of the patterns available at various stages of the investigation (short- and intermediate-term with partial fixed lab data, and after all data were in hand) suggests that the key CSM questions were answered largely by the field method; that is, patterns were discernible that supported both upstream flow and bank-origin collocated plumes. Numerous prior phases of sampling had been performed that had failed to identify the boundaries of contamination. This sampling finally answered the major CSM questions in a single mobilization largely using field-based methods, and further sampling activities will not be required prior to the design phase of site response.