Best Available Technologies septic systems become effective on January 1, 2013 as published in the Maryland Department of the Environment (MDE) COMAR regulations (26.04.02).
Several changes to the regulation are cited in the code but the most significant change requires new residential and non-residential construction outside of the Critical Area (greater than 1000 feet) to install a nitrogen reducing component also known as "Best Available Technology (BAT).
A "grandfathering" policy has been established by MDE. The policy allows any property owner who obtains a ***septic construction permit (for new construction/additions) prior to the effective date of December 28, 2012 to be exempt from the requirement to install the BAT component. The exemption will last as long as the construction permit is valid. Currently, septic system construction permits are valid for two (2) years from the date of issue.
***In Frederick County, a septic system construction permit is applied for and issued in conjunction with a building permit application and cannot be applied for separately, The septic system permit is issued by the Frederick County Environmental Health Division, only after the building permit has been approved by our office.
Questions relating to the new regulation should be directed to Frederick County Environmental Health Division at 301-600-1726.