Technologies and Costs for Removal of Arsenic From Drinking Water

were based on $40/sq ft). The process areas for the design flows in the Very Small SystemsDocument were regressed and found to best fit a linear regression:Process Area (sq ft) = 614.6 * Design Flow + 68The process area for the conceptual designs in the Water Model (6) were also regressed andfitted to a linear regression. The conceptual designs covered a design flow range from 0.045to 1.082 mgd. The linear regression from this source is:Process Area (sq ft) = 726.6 * Design Flow + 59The process area estimates using the regression of the older model data were selected to makecost estimates for buildings, road and fence. Since there would be a minimum building size,extrapolating a linear regression below the lowest data point does not create a significantproblem with the intercept. These process area estimates were larger than the process areaestimates from the Very Small Systems Document for design flows larger than 0.09 mgd. Atthe lower design flows, the process area estimates were slightly lower using the Water Model.The Water Model covered a broader range of design flows, so less extrapolation is requiredat higher design flows than would be the case if the Very Small Systems Document equationwere used. Another factor that also adds to the conservative nature of the process areaestimates is that the data are based on a design that includes regeneration. The space devotedto chemical feeders and storage tanks for regeneration of the media is unnecessary in thisdesign. The process area estimates were compared with the minimum area needed for thevessels using the vessel diameter. The process area estimates are greater than three times theminimum area estimates for the vessels, including the redundant column.14. The building cost to house the activated alumina system is $45.38/sq ft for design flows at orbelow 0.65 mgd. The following equation is used for design flows between 0.65 and 1 mgd:Building cost = 54.204 * Process Area + 14887D-9