Operations, Maintenance and Replacement of Passive Treatment Systems

Table of Contents

Summary
Clean & remove accumulated metals
Replenish limestone
Replace compost
Related Pages
Source and Last Reviewed

Summary #

Even passive AMD treatment systems require ongoing operations, maintenance, and replacement (OMR) planning. This page provides an overview of common OMR activities organized by treatment system type — including metals removal, limestone replenishment, and compost replacement — with links to detailed guidance for each system.

For AMD discharges where passive treatment methods are sufficient, the passive systems require much less continuous maintenance than active treatment. Still, even passive systems require a plan for ongoing operation, maintenance, and replacement (OMR). Such OMR concerns should be analyzed even before the system is constructed, based on water quality information and flow measurements.

Provisions must be made for even the most basic maintenance activities, including mowing grass around a system and removing leaves that may clog conduits. Some systems are surrounded by fences to prevent vandalism. Also, animals may damage a system, especially muskrats, whose tunnels must be blocked with dirt and rocks.

Different types of passive treatment systems require specific OMR activities. The list below includes some of these requirements and the types of systems to which they apply. Follow the links for descriptions of each system, including more detailed OMR information.