| Scope and Method of Study. Water Resources Engineering. Research was performed for the small military installation of Vance AFB to evaluate and optimize the current remediation Long-Term Monitoring Plan. Two shallow aquifer groundwater plumes contaminated with the DNAPL chemical trichloroethylene (TCE) were analyzed with two public domain software programs, Monitoring and Remediation Optimization Software (MAROS) and Geostatistical Temporal/Spatial (GTS) Algorithm, adopted by the Air Force Center of Environmental Excellence. The goal to reduce wells and testing utilized Mann-Kendall, linear regression, Delaunay triangulation, Modified Cost Estimating System weighting, thinning, locally-weighted quadratic equations, temporal variogram, and a comparison with Parsons Three-Tiered approach.;Findings. Irregular test data was reformatted from several sources using Excel. Other remediation construction such as cutoff walls and extraction wells complicated definition of representative plume boundaries. Evaluation of a small portion of dissolved TCE did not account for residual contamination. Recommendations to reduce testing frequency and the number of monitoring wells offered a minimum cost saving of ;Conclusions. (1) MAROS can operate with minimal data sets with less information than required by other Long Term Monitoring Optimization Software as shown by the operation of the GTS software. (2) The effect of limited well test data from contaminated plumes demonstrates that analysis is primarily dependent upon temporal data and frequency. It does not matter how many wells are present if the data is not first organized into periods of testing and set at specific calendar dates. (3) The most efficient form for updating and inputting data into MAROS is Excel format. ERPIMS is extremely difficult to access from a layman's level and excellent support if provided by the Air Force help desk that sponsors the software. (4) In comparison to the higher level GTS statistical optimization program, MAROS is rated the simplest software to operate. Input data is minimal for the general site, geography, stratigraphy, and hydrogeology. (5) The attained results of MAROS remediation do not necessarily correlate with attainment criteria of the regulators. For instance, the MAROS recommendation for deletion of wells differed significantly from the simpler ODEQ criteria of recording less than MCL levels for six straight testing periods. |
