Underground Injection Control (UIC) Program
The Oregon Department of Environmental Quality (ODEQ) issued a permit in June 2005 authorizing stormwater discharges to city-owned UICs. The permit protects groundwater through an aggressive stormwater management program, and uses stormwater as a resource to recharge groundwater and surface water. The City of Portland’s UIC Program has five goals:
- Ensure that UICs are constructed, operated, and maintained in a manner that meets Water Pollution Control Facilities (WPCF) permit requirements and protects groundwater for use as a drinking water resource.
- Use stormwater as a resource by facilitating long-term operation of stormwater facilities that support the natural hydrogeologic cycle, provide baseflow for surface waters, and contribute to normative stream flow conditions by reducing storm flow to piped sewer systems.
- Emphasize management actions that prevent, minimize, and treat pollutants in stormwater before they can be discharged to a UIC.
- Collect and evaluate stormwater data that are representative of the overall UIC system to verify groundwater protection and WPCF permit compliance and to identify where system improvements are needed.
- Ensure that non-compliant UICs are identified, operated, modified, and/or decommissioned in a manner that brings them into compliance.
The UIC Program is organized into three main elements: System Management, System Monitoring, and Response. The UIC Management Plan (UICMP) describes the overall program and outlines how it will be implemented.
1) System Management. Includes citywide best management practices (BMPs) implemented on an ongoing basis to prevent, minimize, and control pollutants in stormwater prior to discharge to a UIC. For example, the BMP category System Inventory and Assessment (SA) focuses on tracking, updating, and refining information related to the location and physical characteristics of existing and new public UICs.
More information specific to the System Management program element can be found in the following documents:
- Systemwide Assessment: a technical document that support the System Management program element
- UICMP Annual Reports: summarizes BMP activities for each year
2) System Monitoring. Includes required stormwater discharge monitoring and BMP monitoring. Data generated from monitoring demonstrates that UICs are operated in a manner that meets WPCF permit requirements and protects groundwater as a drinking water resource.
Technical documents that support the System Monitoring program element are:
- Stormwater Discharge Monitoring Plan (SDMP), comprising a Sampling and Analysis Plan (SAP) and a Quality Assurance Project Plan (QAPP).
- Annual Stormwater Discharge Monitoring Plan (SDMP) Reports: summarizes Monitoring activities and sample analysis for each year
3) Response. Includes the description of response or corrective action procedures as required by the WPCF Permit. UICs that may potentially be a threat to groundwater protection are identified during the implementation of the System Management and System Monitoring elements.The objective of response is to improve or correct conditions at a UIC or group of UICs.
In addition to complying with the WPCF permit, the UIC Program and UICMP must meet the requirements of Oregon Administration Rules (OAR) 340-044-0018(3)(b)(C). These requirements specify that municipalities with 50 or more UICs must prepare and implement a written stormwater management plan that includes a systemwide assessment, system controls, monitoring, and a plan for record keeping and reporting.