9/4/2019 Closure P osure Pathways a thways and d LNAPL P LNAPL Policy licy in Col in Colorad ado CEMS Meeting September 10, 2019 Tom Fox Colorado Division of Oil and Public Safety (OPS) RBCA Closure Standards 1988 1994: ASTM Guide for Risk-Based Corrective 1. Must meet MCLs in groundwater Action Applied at Petroleum Release Sites 2. Soil contamination must allow #1 to be met [ES-38-94] 3. Recover all LNAPL!!! 1995: OSWER Directive 9610.17 encouraged RBCA for USTs 3 Tier II What was the Problem? • RBCA implemented in 1999 allowed computer F&T models • The majority of open releases were over 10 years old • Tier II allows only onsite contamination to remain in soil and groundwater • Sites over 10 years old were difficult to close under Tier I and Tier II criteria • Costs increased as time went on, often with diminishing returns • Return on investment (risk reduction) was seldom considered 5 1
9/4/2019 2014: Tier III and Tier IV Closure Tiers Closure Criteria Established conditions to allow for offsite contamination to remain in place based on a risk evaluation. • Tier III applies to public roadways • Tier IV applies to private property 7 Tier III Tier IV • A public roadway property boundary is • Like Tier III except: the only impacted point of exposure – Fate and transport modeling, empirical data and Private property boundaries are impacted other lines of evidence must be used to support this The tank system has been removed from the • Remediation has occurred to the facility MEP…more on this shortly 10 Tier III and IV Criteria Tier III and IV Implementation Issue 1 1. Property boundary is the only impacted 280.64 Free product removal. POE (no other receptors) “… owners and operators must remove free 2. Use fate and transport modeling product to the maximum extent practicable as determined by the implementing agency…” What about? 1. Contaminant removal to the MEP Resulted in numerous failed and costly remedial 2. Offsite property owners implementations with negligible risk 3. Documentation!! reduction 2
9/4/2019 Maximum Extent Practicable Tier III and IV Implementation Solution All original CAPs must be designed to meet Consideration given to: Tier I or Tier II closure criteria 1. Proper implementation of past remedial efforts Tier III or Tier IV closure criteria may be 2. Feasible technologies tried considered for releases that cannot 3. Possible future risk reduction achieve Tier I or Tier II closure criteria with 4. Access consideration given to MEP 5. Cost Tier III and IV Implementation Issue 2 Ineffective ► Manual Bailing Originally, criteria relied on offsite property owner consent: ► Absorbent Socks ► Short-term Vacuum Not a deed restriction / covenant Truck Events Included indemnification clause for state Owners hired attorneys ► Passive Skimmers Tier III and IV Implementation Solution Tier III and IV Implementation Issue 3 Moved to a notification process in January 2016: How to record the location of offsite Notify offsite owners >30 days prior to contamination? anticipated closure (“closure under consideration”). • Deed restrictions / covenants expensive, Interesting fact: few people contact OPS with questions/concerns time-consuming, and difficult to implement Big picture: engage with offsite property owners ASAP • Getting owner agreement difficult Property value is NOT a risk consideration. 3
9/4/2019 Tier III and IV Implementation Solution Tier III and IV Implementation Solution Fact Sheet created for each Tier III and IV closure Tier III and IV Implementation Solution Closure types since October 2014 1. OPS became a member of Colorado 811 2. Area of impact mapped to Colorado 811 Tier II 18% 3. OPS called by construction company to Tier III discuss work and potential exposure 7% 4. Email fact sheet to company and publicize Tier I Tier IV website 71% 4% Benefit: Deal with changes in exposure scenarios when they arise Total 1317 LNAPL Tier III and IV Closures Colorado adopted ITRC LNAPL principles and recommendations in 2015: 1. LNAPL saturation objectives should be addressed until Tn < 0.8 ft 2 /day (about 1.5 gpd recovery). 2. When recovery is negligible, focus on compositional concerns to achieve closure. 3. Release events can be closed with measurable LNAPL if the LNAPL recovery is negligible and there are no compositional concerns. 4
9/4/2019 LNAPL Baildown Testing LNAPL Test Interpretation Follow ASTM E2856 and API Publication 4762. 1. Provide the API workbook as an Excel document in Use ITRC LNAPL Site Management document. the MRR. Raw data should be on a new, separate tab. Search youtube for “baildown testing”. 2. Be careful to only modify yellow cells. Wells containing >6 inches of LNAPL must be tested. • Some cells are not protected, but must not be Wells containing >2 but <6 inches need special testing • modified. equipment, consult your technical reviewer on need for testing. 3. Collect data long enough…(early data is sand pack Wells <2 inches likely not recoverable (but OPS may require • drainage). testing anyway). Data may need to be collected for several hours on a logarithmic 4. Read the API publication carefully! • schedule. Lack of accumulation after several hours likely indicates Tn < 0.8 ft 2 /day. Policies Mesh Other News 1. New RCGs adopted for use on July 1, 2019. OPS now allows unrecoverable LNAPL and 2. OPS approving more high-resolution site impacted soil to remain offsite under Tier III and characterization efforts. Tier IV. Allowing LNAPL infers allowing impacted soil. 3. OPS approving horizontal boring and Compositional hazards must still be assessed. Vertebrae™ wells. 4. OPS allowing treated purge water disposal OPS allows a new tank system to be installed on onsite in pilot programs. Protocol required. Tier 4 (closed) facilities. Consult with technical 5. RBSLs to be reviewed in 2020, newer reviewer. toxicology data available. Still Other News 6. PSTC Policy 29 allows up to $30,000 to remove a UST system. 7. 2019 incentive program waives the $10,000 deductible when system is removed. 8. OPS completed Outreach at 5 locations in the state (June to August 2019). 9. Administrative/enforcement support for the Underground Damage Prevention Safety Commission (811 system). 10.Grants for EV infrastructure available via “Charge Ahead Colorado” tom.fox@state.co.us 5
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