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.~~ Table 1 -Screened Options c:! j/o lll- Criteria '" /hili '" "'~ 8~ -01 ::J'O 5 a 10 "0 = 'Ii-- u I!! 3= .. ~g E: Kev (Differing opinions within the team are represented by 2 symbols) ~ ~oI.I 'C "'<2 6 ~ c: Options to solve 'E-a .9 .S o'/:l u 0 .S2 ~ "0 C. ~o;:: i ~ ~ .. '" c: 0 Y = Yes, meets criteria the Prohlem ""0 -:; <.~~ u- tJ '" N = No, doesn't meet criteria ..c: ~~ .. .. ~ :s .- /h ~ ..... -;; c en'r: w:.=.- ~s u c: U = Undetennined or doesn't sufficiently address the criteria e 'Ii 8 '" u os Q., ~ Ootions to control sources of selenium): Comments / Primarv reasons for eliminatinf! as an option Change irrigation to sprinkler systems U Y U Y y N May not be compatible with soils/crops grown in this area/not sufficiently effective Line or pipe irrigation canals & ditches U y y y y N Not sufficiently effective at OMWA Best Management Practices (BMPs) U y U Y y/U N Long tenn effectiveness is questionable Inot sufficiently effective Options to treat contaminated water: Use plants to absorb selenium U y y y U N Concern about bird impacts I unproven technology & plant disposal issues Intercept/treat (e.g. w/activated aluminum) y y y y Y/U Y Concerns if it will work & how to dispose of waste from the treatment process Reverse osmosis/other physical treatment Y Y Y Y Y Y Concerns about cost and need for waste brine pond Biological treatment U Y U Y U N Ponds may need netting & would have to be off-sitel unproven technology OPtions to transport/dispose contaminated water: Pipe drains & seep water to the river Y Y Y Y Y Y Concern about long tenn liability of a pipeline as a point source discharge Divert & reuse drain water elsewhere Y Y Y Y Y Y Concern about finding sufficient alternate uses Line collector ditch (to prevent inflow) N Y N Y N N Not effective Collect and use deep well injection Y Y Y U Y Y Concern about potential high cost Remove contaminated sediments N/U Y N/U U Y N Concern: recurrence & disposal of contaminated sediment/not sufficiently effective Collect and evaporate water in ponds y y Y Y Y Y Retained but lots of potential problems including pond siting, size, bird usage, etc. Options to dilute contaminated water: Add Colorado River water to flush/dilute U U U Y Y Y/U Uncertain whether sufficient water can be diverted into the area year round Remove beaver dams Y/u Y U Y U Y Cuts retention time; does not affect overall loading passing through the wetlands Dilute drains at their source U Y U U Y UIN Unrealistic amount of dilution water needed to sufficiently reduce concentrations Options with no construction needed: These are non-structural options. Improve irrigation efficiency N Y N Y Y N Meet crop need w/ correct amount of water at right time /not significantly effective Change land use (agricultural to residential)U Y U U U N Willing landowners only / not sufficiently effective Buy ag lands that contribute selenium y Y Y Y Y Y Willing sellers only; need to isolate hot spots; social/economic, land mgt. concerns Options for replacement water supplv: 1) Deliver river water via a gravity ditch, 2) Pump water (consider a hydraulic pump), 3) Collect & deliver irrigation tailwater, 4) Deliver spills from Orchard Mesa canals. These are not options to solve the problem but options for a replacement water supply, which is needed as a component of several alternatives. These were not evaluated using the criteria above, but will be examined separately as water supply alternatives. I Source controls are only partially effective in reducing deep percolation, and though the volume may be reduced, continued irrigation will add drainage to the ground water which picks up selenium. There would most likely still remain a need to address the remainder of the contaminated drainage flowing into a specific area, like OMW A.