Two related contingent valuation surveys were conducted in ten Cornbelt counties to estimate the potential enrollment in the Conservation Reserve Program (CRP) and a 30-year easement program of filter strips and cropland in areas valuable to groundwater contamination. It was found that potential CRP enrollment climbs dramatically in the range $90-140/acre/year. Filter strip enrollments are greater than recharge area enrollments at any given rental rate. Thirty-year easements receive substantially less enrollment than CRP when a lump sum of 10 times the CRP rate is offered. Tree planting is a low percentage of CRP enrollments, but is a higher percentage of 30 year easement enrollments. Allowing enrollments to be used for set aside requirements improves enrollment in the CRP by 32% for filter strips and by 6% for recharge areas; these differences are most marked at lower annual rental rates. Farmland owners who indicated they would not enroll gave primarily financial reasons for making that decision, further indicating that enrollment is very responsive to rental rates for the CRP and lump sums for easements. However, allowing variable time periods for contracts, adjusting rental rates for inflation or local cropland rental rates, publicizing maximum annual rental rates (MARRs), and simplifying the enrollment process could increase enrollments.