Onsite Systems

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The Onsite Systems Division provides technical assistance and direction to County Health Departments and Local Approving Authorit​ies for the implementation of delegated programs for Onsite Sewage Disposal Systems (OSDS) and individual wells. This is of the utmost importance in carrying out our mission of protecting groundwater quality and public health.

Some of the functions of the Onsite Systems Division are:

• Co-review of OSDS equal to or greater than 5,000 gpd for compliance with the Large System Guidelines.
• Provide guidance on the applicability and design of alternative and innovative systems 
• Provide guidance on the proper interpretation and enforcement of COMAR regulations 26.04.02, 26.04.03, 26.04.04 and 26.04.05, concerning onsite sewage disposal systems, subdivision of land, well construction and shared facilities
• Provide guidance for site and soil evaluation, construction inspections, and enforcement issues
• Provide or approve training for sand mound construction, at-grade mound construction, best available technology (BAT) installation, operation and maintenance of BAT systems and inspection of septic systems for property transfers
• Maintain a list of Individuals who have taken an approved course in the proper inspection of OSDS for property transfer
• Well Construction inspection and permitting 

Training 

Courses offered by the Department and their application forms can be found here.

Site Evaluation for Onsite Sewage Disposal Systems

• Site Evaluation Manual 
• Web Soil Survey (NRCS) 

List of Certified Installers

• List of Certified Sand Mound Installers
• List of Certified At-grade Installers 
• MDE Certified BAT Installers (Non Distributor Certified)

• MDE Certified O&M Service Providers for BAT (Non Distributor Certified)
• Individuals Who Completed MDE-Approved Course for Onsite Property Transfer Inspections

Sand Mound Sewage Disposal Systems

• Sand Mound Manual
• Updated Sand Mound Guidance
• Sand Mound Infiltrometer Testing Procedure
• Technical Advisory on Pressure Distribution Networks
• Preconstruction Checklist for Sand Mound Installers
• Inspection Checklist for Sand Mound Systems
• Sand Analysis
  
• ​Sand Certified Within 45 Days
  
• Potential Sand Providers in Maryland​
• Sand Size Analysis for Onsite Wastewater Treatment Systems​​

At-grade Mound Sewage Disposal Systems

• At-grade Manual
• Pre-construction Checklist
• Installation Sequence
• Inspection Checklist for At-grade Mounds

Guidance for Onsite Systems

• Decision Framework for Evaluating Project Flows utilizing Onsite Systems and Wastewater Flow Guidance
• MDE Guidance on Wastewater Flows for Use in Designing Onsite Systems
• 1500 Best Available Technology (BAT) Memorandum
• Sampling Requirements for >1500 gpd Individually Engineered BATs
• ​​Large Onsite Sewage Disposal System Guidelines
• Municipal Groundwater Discharge Permit Application
• Approved Course Providers

For Installers

• Onsite Installer
• NEHA's National Installer Certification (CIOWTS) 
• Guidance for Conducting Septic Inspections for Property Transfer 
• CIDWT's inspection checklists
• CIDWT O&M service provider checklists

For Homeowners

• NESC Guidance for Buying or Selling a Home on an Onsite Treatment System
• University of Maryland's Septic Records and Maintenance Guidelines
• Local County Approving Authorities
• NAWT Onsite Treatment Tank Pumping and Cleaning Code of Practice
• CIDWT Guide to Evaluating Service Contracts
• National Environmental Services Center (NESC)  
• EPA's SepticSmart Program 

Contact Info

If you have additional questions or would like more information, please contact the Wastewater Permits Program, Onsite Systems Division at 410-537-3778.

Additional Information and Related Links

• The Maryland Onsite Wastewater Professionals Association
• The Consortium of Institutes for Decentralized Wastewater Treatment  
• The Mid Atlantic Association of Professional Soil Scientists
• The Small Scale Waste Management Project
• National Onsite Wastewater Recycling Association
• The USEPA Onsite Wastewater Treatment Systems Manual
• National Association of Wastewater Technicians 
• Delaware Technical Community College - Environmental Training Center 
• COMAR 26.04.02-26.04.05
• Bay Restoration Fund
• Well Construction
• Groundwater Discharge Permits
• MDE home