A law enacted over a year ago (St. 2008, c.453) requires homeowners with oil burners installed before 1990 to make a small change to their systems to prevent leaks. Originally, the law was to take effect July 1, 2010. On June 24, 2010, the law was amended, so that while insurance coverage requirements are still effective July 1, 2010, the requirements for homeowners don't take effect until September 30, 2011.
According to the Mass. DEP, under the Homeowner Oil Heating System Upgrade and Insurance Law, "Owners of 1- to 4-unit residences that are heated with oil must already have or install an oil safety valve or an oil supply line with a protective sleeve... Installation of these devices must be performed by a licensed oil burner technician." "It is important to note that heating oil systems installed on or after January 1, 1990 most likely are already in compliance because state fire codes implemented these requirements on new installations at that time."
The good news is that the law also requires insurers who offer homeowner's insurance to also offer coverage for oil leaks to those who have certified that they have made the repairs or are exempt from the requirement.
More information, including a diagram of necessary repairs, is available at the Mass. Department of Environmental Protection site.