None of the three dozen sales of oil wells proposed in California this year has materialized due to the considerable clean-up costs for the wells estimated by the state’s oil and gas regulator. Last year, California sought to prevent a rise in the already high number of so-called orphan oil wells. The state also looked to keep from passing off to taxpayers the liability for plugging and abandoning oil wells should operators not have sufficient funds to plug and decommission non-producing or marginal wells and clean up the sites. That’s…