Contaminated Water on Construction Sites

These are resources to aid contractors in handling contaminated water on construction sites. Please contact us with any questions regarding contamination on your construction site.

Documents and helpful links

Treatment Systems for Contaminated Construction Runoff (TSCCR) (Excel)
Provides guidance for filling out a Notice of Intent (NOI) Application Form, section VI; and/or those filling out a SWPPP in conjunction with the General Construction Stormwater Permit, S9, Part 9. The table shows treatment systems (listed across the top) that may be effective in treating various specific contaminants (listed down the side). Users should evaluate the effectiveness of any treatment system they plan to implement and confirm that the chosen treatment system does not cause or contribute to a violation of the Water Quality Standards. View the table | Download the data

Treatment Types
EPA's Drinking Water Treatability Database of treatment processes. This database provides definitions and detailed information on Treatment Processes currently available. The EPA provides this information as a courtesy; Ecology does not guarantee or endorse any of the listed treatment systems.

Technology Assessment Protocol - Ecology (TAPE) database
The TAPE program provides a peer-reviewed regulatory certification process for emerging stormwater treatment technologies.

Hazardous Substance Information and Educational Office (HSIEO)
HSIEO is an information resource for workers, schools, and communities.

Effluent Calculation Tools: Effluent Characterization for Permit Application (Attachment A) | Permit Calculator Workbook

Effluent Limitations Guidelines from EPA
Effluent guidelines are national standards based on the performance of treatment and control technologies for wastewater discharges to surface waters and municipal sewage treatment plants. Your local jurisdiction may have different guidelines for discharge. Check with your local jurisdiction before discharging from your site.

RCW 70.105.010
Definitions from the Washington State legislature regarding Dangerous Wastes and Toxic Substances

Construction Stormwater General Permit

Frequently Asked Questions

  1. What do I report to Ecology if I answered yes on the Notice of Intent (NOI) that contaminated soils will be disturbed or contaminated groundwater will be discharged because of the proposed construction activity?

  2. Is there a database of contaminated sites so I can see if my site has already been reported to have contaminants?

  3. Do I have to conduct further testing for contaminants on my construction site to receive a permit?

  4. If my soil is contaminated, do I have to control my stormwater runoff?

  5. If my site meets MTCA is it clean?

  6. If my site has a No Further Action (NFA) letter, is it automatically considered clean?

  7. Do my WQWebDMR reports have to include my contaminant concentrations found in the construction stormwater?

  8. Where do I find BMPs for managing and containing contaminants?

  9. Can treatment systems can be grouped together?

  10. Where do I find the contaminant concentration levels I need to treat to?

  11. Can I discharge my treated runoff into waters of the State?

  12. Can I infiltrate contaminated dewatering water back into contaminated soil?

  13. If I have a flow through treatment system, do I need to have secondary containment for 110% containment of the total volume?

  14. Where do I dispose of my pollutant refuse?

  15. How should I contact Ecology if I have a breach in my contaminant containment system?

  16. When can I expect to hear back from Ecology regarding my Notice of Intent (NOI) Form?

Contact Information

CSWGP • NOI • Q/A • Effluent Limitations Guidelines
TSCCR • Contaminant report • Treatment types
Amy Moon
TAPE Douglas Howie

Return to Construction Stormwater Page