At Any Time
Emergency or Interim Removal Action

Note: Most Department of Defense sites in Alaska follow the process outlined in the federal law CERCLA. The steps have different names but the process is similar.
(Learn more about the CERCLA process.)

Notification
The person in charge of the operation or facility notifies DEC when a discharge, spill, release or contamination is discovered.

18AAC 75.300

See 18 AAC 75, Article 3 (PDF 314K),
eff.10/9/08

Initial Response
The responsible person must respond to the spill: contain, investigate, and clean up contamination under DEC oversight.

DEC will require additional cleanup when soil and groundwater contamination remains after the source of contamination has been abated, or when a release of a hazardous substance was caused by past activities.

18AAC 75.310
18AAC 75.315

18AAC 75.330

Site characterization is often an iterative process. Planning, investigating, and reporting may occur more than once. Work with your DEC project manager to determine how formal the workplan and report should be for your site characterization effort.

The two guidance documents listed at right are currently the best statement of the overall procedures used during investigation of a contaminated site. Although they lack information on non-petroleum contaminants, they are useful to all cleanup efforts. (You will find that these documents contain many similarities. DEC plans to combine these guidances in the future.)

Underground Storage Tanks Procedures Manual

Cleanup of Petroleum Contaminated Sites

The responsible person has a qualified person (typically a contractor) prepare a site characterization workplan for DEC approval. The intent of a workplan is to identify the source and the extent of contamination and evaluate the threat to human health and the environment. See link to regulations at right for a full list of workplan requirements.

Planning for site characterization involves the following steps:

18AAC 75.335(b)

See 18 AAC 75, Article 3 (PDF 314K),
eff.10/9/08

Human Health Scoping Form

Ecological Scoping Guidance

Workplan Submittal
Workplans must be approved by DEC and must include some discussion of the following:

• Summary of existing information
• Sampling approach (to gather reliable data to identify the source, contaminants of concern, the extent of contamination, and the threat to human health and the environment)
• Identity and qualifications of key participants
• Quality assurance and quality control procedures

For help in determining the contaminants of concern for the investigation, see the Cumulative Risk Guidance.

For petroleum spills, a workplan should be prepared in accordance with the Underground Storage Tanks Procedures Manual and the document, "Cleanup of Petroleum Contaminated Sites." Guidance for other compounds or for specific characterization topics can be found in the Site Characterization and Cleanup link to the right.

Underground Storage Tanks Procedures Manual

Cleanup of Petroleum Contaminated Sites

Screening Procedures

Site Characterization and Cleanup

18AAC 75.335(c)

Laboratory Data and Quality Assurance Policy--Tech Memo

Exposure Pathway Analysis
Using the analytical data and other information collected during the field effort, the qualified person evaluates each exposure pathway identified in the Conceptual Site Model. Before site closure, the qualified person must calculate the cumulative risk to humans from all exposure pathways as described in the Cumulative Risk Guidance. For some pathways, a qualitative evaluation may be enough to either determine that further investigation or cleanup is needed or that the contamination is limited enough that no significant exposure is expected. Consult with the DEC project manager regarding the extent of evaluation required for each pathway.

A human health or ecological risk assessment is sometimes conducted to evaluate potential effects from the contamination and to develop cleanup levels. A human health risk assessment looks at the risks to humans from contamination at the site, and an ecological risk assessment looks at the risks to plants and animals. The qualified person should consult the Risk Assessment Procedures Manual when doing either type of risk assessment.

Cumulative Risk Guidance

Risk Assessment Procedures Manual

See 18 AAC 75, Article 3 (PDF 314K),
eff.10/9/08

18AAC 75.340

Cleanup Level Guidance

Risk Assessment Procedures Manual

Download 18 AAC 75 Article 3 (PDF 314K)

Groundwater cleanup levels are based on drinking water standards.  To determine groundwater cleanup levels, use Table C in 18 AAC 75.345 .
(For a printable version, click the link at the right and scroll to Section 345.) The qualified person may demonstrate that groundwater is not a source of drinking water in accordance with 18 AAC 75.350.

Download 18 AAC 75 Article 3 (PDF 314K)

18AAC 75.350

Ecological Scoping Guidance

Surface water - must meet the state's Water Quality Standards.

18AAC 70 Water Quality Standards

Report Preparation and Submittal
Site characterization reports are prepared by a qualified person on behalf of the responsible party and submitted to DEC for approval. See link to regulations at right for information on requirements. Each report includes:

• Site background, including physical setting and historical information;
• A description of the revised Conceptual Site Model;
• Methods used for the characterization, including any field adjustments to the site characterization workplan; and
• Sampling analysis, analytical results data deliverables, and a completed Laboratory Data Review Checklist (see Step 5).

The final site characterization report should also include:

• Conclusions concerning the nature and extent of contamination;
• Conclusions concerning the human and environmental hazards posed. A formal risk assessment, if conducted, must also be reported;
• Calculation of cleanup levels using the applicable method(s);
• Analysis of cleanup alternatives and recommendation of cleanup technique(s) to be used at the site. Cleanup techniques are recommended based on their protectiveness, practicality, effectiveness, conformity with state regulations, and consideration of any public comment; and
• Recommendations on land use and activity (also called " institutional") controls that would allow reuse of the land while protecting human health and the environment

A risk assessment report may serve as the final site characterization report at a site.

18AAC 75.335(c)

Download 18 AAC 75 Article 3 (PDF 314K)

Laboratory Data Review Checklist

DEC will approve the final site characterization or risk assessment report if it determines that the work described in the report and the cleanup techniques proposed are protective of human health and the environment. The department may modify proposed cleanup techniques or require additional cleanup steps. DEC will consider public input.

In a cleanup following the federal CERCLA process, the decision involves first issuing a "Proposed Plan," inviting public comment, and writing a final "Record of Decision."

18AAC 75.335(d)

Download 18 AAC 75 Article 3 (PDF 314K)

The cleanup process varies greatly in level of detail. The documentation for simple cleanups may be a few pages containing abbreviated descriptions. For complex cleanups, substantial, detailed documentation may be required to fully explain more complex plans and technologies.

Chapter One of the Underground Storage Tanks Procedures Manual and the Cleanup of Petroleum Contaminated Sites provide our best guidance for cleanup and recharacterization of a site and may also be helpful for other contaminant types.

Underground Storage Tanks Procedures Manual

Cleanup of Petroleum Contaminated Sites

The cleanup plan is the first part of the cleanup phase and presents the technical specifications for the cleanup action. Once DEC approves the plan, the responsible person implements the cleanup action. Cleanup plans may also be amended if the cleanup action proves to be insufficient. A cleanup plan includes these steps:

Cleanup Schedule Submittal
Before work begins, the responsible person submits a schedule for conducting field work, monitoring, cleanup, and submittal of interim and final cleanup reports for DEC approval. Additional approval will be needed if the process is modified.

Cleanup Plan Submittal
The responsible person has a qualified person (typically a contractor) prepare a cleanup plan for DEC approval. The cleanup plan includes these elements:

• Specifications of the proposed cleanup technique
• Provisions for minimizing contaminant migration to previously unaffected areas
• Provisions for disposal of contaminated soil and groundwater

In addition, a sampling and analysis plan for confirmatory sampling, waste management plan, site control plan, site monitoring plan, or other requirements may be necessary. See the regulatory links at right for more specifics on sampling and analysis, cleanup operation requirements, offsite or portable treatment facilities, soil storage and disposal, and land use and activity controls.

For petroleum spills, the cleanup plan should be prepared in accordance with the Underground Storage Tanks Procedures Manual and the Cleanup of Petroleum Contaminated Sites. Remediation guidance for other compounds or for more specific topics can be found in the Remediation Operations link to the right.

Field Effort
The responsible person ensures that the work is conducted or supervised by a qualified person, guided by the workplan, and that sampling and analysis are conducted by a qualified impartial third party. DEC monitors progress toward the objectives, schedules, and reporting requirements set out in the cleanup plan. The level of oversight will depend on the complexity of the site and the cleanup action, the hazards posed by the site, and the degree of public interest, along with other considerations.

Download 18 AAC 75 Article 3 (PDF 314K)

18AAC 75.355 - Sampling and analysis)
18AAC 75.360 (4) - Elements of a cleanup plan)
18AAC 75.365 - Offsite or portable treatment facilities
18AAC 75.370 - Soil storage and disposal
18AAC 75.375 - Institutional controls.

Underground Storage Tanks Procedures Manual

Cleanup of Petroleum Contaminated Sites

Remediation Operations

Report Preparation and Submittal
The responsible person submits interim cleanup reports, as necessary, to DEC. These reports are prepared by a qualified person and describe cleanup actions, remedial system operation and maintenance, monitoring, and any confirmatory sampling or recharacterization of the site. Steps 5 and 6 above should be updated in the report when any recharacterization occurs.

When cleanup is complete, a final cleanup report and closure request must be submitted to DEC for review. See link to regulations at right for information on final reporting requirements. This report should include the following:

• Information about the release, name of any responsible parties, and name of current owners and operators at the site;
• A description of any environmental damage;
• A free product report that summarizes the presence and disposition of free product;
• A description of cleanup activities, including required permits, and confirmation that hazardous waste was handled in accordance with the federal law RCRA.
• A description of the ultimate fate of any contaminated materials removed from the site for cleanup
• Locations, concentrations, and amounts of contaminated materials left in place;
• Field screening and laboratory analytical results; and
• A description of any significant exposure pathways that remain at the site and a demonstration of compliance with applicable institutional controls.

18AAC 75.380

Download 18 AAC 75 Article 3 (PDF 314K)

DEC may consider cleanup of a contaminated site complete when efforts to reduce hazardous substance contamination have either achieved the strictest levels established in state regulation, or the possibility of human exposure to any residual contamination is highly unlikely. DEC will then give the site “Cleanup Complete” status. DEC will close the site, and any legal proceedings are closed. DEC recovers the cost of its oversight or damages from the responsible person. The landowner gets official notice of the closure. See link to regulations at right for information on site closure.

Cleanup Complete – Institutional Controls
If DEC requires the responsible person to maintain land use and/or activity controls to protect human health and the environment from future exposure, the department would then grant a "Cleanup Complete – Institutional Controls." (see "institutional controls.")

Note: If you are a responsible party that is required to periodically report to DEC, you may submit documents electronically to dec.icunit@alaska.gov.

For more information see closure of a contaminated site.

For follow-up questions, please contact the Contaminated Sites Program office closest to you: