[Figure Title] Figure 3-2: Recommended Decision-Making Framework for Containment and Treatment of Contaminated Water for Wastewater and Stormwater Systems
Containment and Disposal of Large Amounts of Contaminated Water: A Support Guide for Water Utilities page 11
[Header 1] Initial response
[Header 2] Identification of Contamination
[Box 1] Contamination confirmed in wastewater or stormwater water system
[Header 1] Remediation/Cleanup
[Header 2] Containment for Treatment
[Decision 1] Can water be contained in situ?
If [Decision 1] is yes, then [Box 2] Contain contaminated water in situ (Section 3.1) then [Box 3] Determine treatment (Section 3.3) then [Decision 3] Can water be treated in situ (Section 3.1).
If [Decision 1] is no, then [Decision 2] Can water be contained in temporary storage on site (Section 3.2).
If yes to [Decision 2] then [Box 4] Transfer contaminated water to temporary storage on site (Section 3.2) then [Box 5] Determine treatment Section 3.3) then [Decision 4] Can water be treated in temporary storage on site (Section 3.2).
If no to [Decision 2] or no to [Decision 4] then [Box 6] Contain to transport off site for treatment and/or disposal (Section 5.2) then [Decision 5] To dispose or to treat.
If [Decision 5] to dispose then [Box 13] Discharge through a WWTP (Section 4.2) or [Box 14] Disposal at a hazardous or medical waste facility (CHEM, BIO, TOX)(Section 4.3) or [Box 15] underground injection (Section 4.4) and Box [16]Volume reduction and solidification (Section 4.5, RAD only).
If [Decision 5] to treat then [Box 7] Determine treatment (Section 3.3) then [Box 8] Apply treatment approach (Section 3.3) then [Box 9] Sample and evaluate residual contaminant concentration (Section 3.3) then [Decision 6] Has water been treated to clearance goals (Section 3.3).
If yes to [Decision 6] then [Box 10] Assess water to determine disposal method (Section 3.3) then [Box 11] Determine method of disposal (Section 4.0).
If no to [Decision 6] then [Box 7] Determine treatment (Section 3.3)
If yes to [Decision 3] or yes to [Decision 4] then [Box 8] Apply treatment approach (Section 3.3) then [Box 9] Sample and evaluate residual contaminant concentration (Section 3.3) then [Decision 6] Has water been treated to clearance goals (Section 3.3).
If no to [Decision 3] then [Decision 2]
[Header 1] Remediation/Cleanup
[Header 2] Disposal of Water
From [Box 11] Determine method of disposal then [Box 12] Direct discharge to surface water (Section 4.1) or [Box 13] Discharge through a WWTP (Section 4.2) or [Box 14] Disposal at a hazardous or medical waste facility (CHEM, BIO, TOX)(Section 4.3) or [Box 15] underground injection (Section 4.4) and Box [16]Volume reduction and solidification (Section 4.5, RAD only).
[Footnote]
If it is decided that treatment will occur off site, it may be disposed of at a WWTP. However, prior to considering disposal through a WWTP as an option, utilities should check with the proposed receiving WWTP to ensure that contaminated water can be safely treated and/or discharged according to the terms contained within the facility’s discharge permit issued by EPA or an authorized state or tribe. WWTPs are not allowed to discharge contaminates above the thresholds established within their NPDES permits.