ANNAPOLIS, MD (January 18, 2005) -- Maryland Secretary of the Environment Kendl P. Philbrick today requested support for proposed emergency regulations to prevent MTBE (methyl tertiary butyl ether) and other petroleum products from reaching groundwater supplies in certain parts of Maryland. The regulations will require, among other things, more frequent testing for vapors as well as liquid leaks and rigorous safeguards against leaks.
“For Maryland families that rely on wells, these new measures will provide additional assurance that their water supplies are clean and safe from MTBE and other petroleum products,” said Secretary Philbrick. “We have the ability to keep pollutants out of our drinking water and are going to do so. These are tough, but necessary regulations to strengthen our environmental laws.”
In his testimony, Secretary Philbrick told the Joint Committee on Administrative, Executive and Legislative Review (AELR) that the regulations also require installation of double-walled pipes on all new regulated motor fuel underground storage systems and built-in sensors to warn of leaks. The emergency regulations will also require increased groundwater sampling, mandate regular testing of tanks and fittings, and define steps that gas station owners and others must take when underground storage systems are suspected of contaminating groundwater.
The regulations will apply in areas where wells are the primary source of household drinking water and local geology makes it impractical for homeowners to find a new water source. MDE will identify the areas and notify affected tank owners or operators.
Service stations and other underground storage facilities in areas covered by the regulations will have 30 days after the effective date of the regulations to begin quarterly sampling of water in on-site domestic wells and tank field observation pipes. They will also be required to conduct annual tightness tests for fittings in catchment basins and containment sumps. They will also be required to install and sample three groundwater monitoring wells. Results must be reported to MDE.
If MTBE at levels greater than 20 parts per billion (ppb), more than 5 ppb of benzene or more than 100 ppb of total BETX (benzene, toluene, ethyl benzene and xylenes) are found in the monitoring wells, the operator will be required to develop a corrective action plan. They will also be required to perform an advanced helium leak detention test, which is used to identify vapor leaks.
In addition to repairing all leaks immediately, the operator will be required to install a soil vapor extraction system in the tank area to remove vapors from the earth or other advanced technology to keep vapors within the tank system.
Since last June, MDE has been investigating the presence of MTBE in private wells in the Upper Crossroads area of Harford County. The investigation has focused on an Exxon service station on Fallston Road, where a number of vapor leaks have been found and repaired.
Pursuant to the federal Clean Air Act, MTBE was added to gasoline in the early 1990s and is used to reduce carbon monoxide emissions from vehicles. MTBE was first added to gasoline in the 1970s to replace lead. MTBE makes important environmental and economic contributions by improving Maryland’s air quality and keeping gas prices affordable.
The U.S. Environmental Protection Agency has concluded that there is no measurable health effect from low level MTBE exposure. The EPA’s health advisory states that levels of contamination at or below 20 parts per billion (ppb) provide a large margin of safety from adverse health effects.