When the Department has reason to believe that there is a release or substantial threat of release into the environment of any hazardous substance, the Department may: Add the location of the release or the threatened release to the State Master List of proposed sites; Assess risk to human health and the environment; Decide whether a response should be carried out under State superfund or other enforcement authority; Evaluate and perform or manage removal or remedial response actions; and Request assistance from the federal or local governments. Methods of discovery by the Department of a site that has the potential for, or has demonstrated, release of a hazardous substance include: Report by owners, employees, or users of the site; Report or complaint by citizens, or State or county agencies, of an observed or suspected release or discharge of hazardous substances, or of information concerning health-related effects; and Investigations or inspections by the Department to identify hazardous sites. Placement of Sites on State Master List. The Department may place a site on the State Master List if the Department has reason to believe that a hazardous substance has been or may be released at a site or if the Department has been notified that hazardous substances may be present. If a site is placed on the State Master List a State site assessment may be conducted. Inclusion of a site on the State Master List does not constitute a final decision that response action is necessary. The State site assessment is an initial evaluation of a release or potential release. This evaluation may include a site visit, records search, sampling, and subsurface borings. The Department may use assessments and investigations conducted pursuant to the National Contingency Plan, and information collected by federal, State, or local governments pursuant to other enforcement activities, investigations, or responses. The information gathered during a State site assessment may include: Site history and nature of waste handling; Description of known contaminants and their pathways of migration; Identification of human and environmental targets; Recommendation on whether further action is warranted; and Other information relevant to the source, any potential health or environmental impacts, and responsible persons. After a State site assessment, the Department may indicate that no further remedial action is planned for a site based upon the available information. Further Response Action. If a site is to be considered for further response action, the Department: Shall report the results to the chief health or environment officer of the county in which the site is located; and May proceed in accordance with Regulation .04, .05, or .06 of this chapter. The Disposal Site Registry (DSR) is a listing of hazardous waste sites in the State, published in the Maryland Register, which ranks sites in priority for State remedial action. All sites in the State listed by EPA on the National Priorities List shall be listed in the DSR. The Department may list any hazardous waste site in the DSR on the basis of public health and environmental threat. The Department shall rank sites listed in the DSR based on the Department's determination of the relative threat to human health and the environment, taking into account potential hazards to the public health and the environment, the risk of fire or explosion, toxic hazards, and the criteria established under the federal act. For sites that have been ranked by EPA, the Hazard Ranking System score shall be used as guidance. A removal action may be performed at any stage of the response process, if the Department determines that there is a release or substantial threat of release of hazardous substances into the environment that should be removed, stabilized, or otherwise mitigated. In an emergency, the Department may perform a removal action immediately. If the Department determines that time allows, before beginning a removal action the Department shall make an effort to identify the responsible persons and determine whether those persons will perform the removal action properly and in a timely manner. If a person other than the Department performs the removal, the Department may perform a managerial or oversight function and has the authority to approve, disapprove, or alter the manner in which the removal is being conducted. Unless the Department determines that a removal action will be done properly and in a timely manner by a responsible person, the Department may perform the removal. Extent of Removal. Removal is terminated when the Department determines that the threat of release no longer exists or is otherwise mitigated. If the Department determines that the removal action does not fully address the threat and the release may require further remedial action, there shall be an orderly transition from removal to remedial response activities. The remedial response process consists of several phases, including: Determination of the extent of the potential impact on public health and the environment; Selection of the remedy, design, and implementation of the remedy; and Maintaining and operating the remedy. The Department may modify response procedures set forth in §A of this regulation at sites not listed by the Environmental Protection Agency on the National Priorities List, if the Department determines that this modification will: Result in a more efficient response; and Be protective of human health and the environment. Responsibility for Performing Remediation. Responsible persons may be required to conduct and directly fund a remediation pursuant to an order issued by the Department, EPA, or a court. An order requiring remedial response may set forth specific conditions for the performance of the remediation. At sites listed on the National Priorities List, the Department may exercise State authority and oversee response actions. Unless the Department determines that a remedial action will be done properly and in a timely manner by a responsible person, the Department may perform the remediation and seek cost recovery. Management of Remediation. The Department may provide management oversight of response activities. Management oversight includes, but is not limited to: Review, comment, and approval of reports, plans, documents, and data relating to the response action; Site visits; Sampling; and Enforcing compliance with cleanup standards, State or federal laws, regulations, and other requirements. Evaluating Releases or Threats of Releases. Investigations shall be conducted to characterize site conditions leading to development of remedial alternatives. These activities to evaluate the nature and threat posed by the hazardous substances may include field and other investigations to: Characterize physical features of the site; Characterize air, surface water, and ground water; Determine waste characteristics including quantity, toxicity, persistence, propensity to bioaccumulate, and mobility; Identify environmental pathways and exposure routes; and Determine the extent of source contamination. The Department shall determine the applicability of cleanup standards and State or federal laws, regulations, and other requirements. In establishing cleanup standards and other requirements the Department may use the following: Federal or State maximum contaminant level goals (MCLGs) and maximum contaminant levels (MCLs); Background levels of contaminants; Risk evaluations performed by the Department based upon site-specific information and current scientific information; and Other federal or State standards that may be appropriate or relevant. Determining the Type of Response Action—Selection of Remedy. Remedial alternatives shall be developed and evaluated for remedy selection. Factors to be considered in evaluating and comparing alternatives include: Protection of human health and the environment; Compliance with cleanup standards and State or federal laws, regulations, and other requirements; Long-term effectiveness and permanence; Reduction of toxicity, mobility, or volume through treatment; Short-term effectiveness; Implementability; and Cost. To be considered for selection, it is mandatory that any remedial alternative meet the criteria listed as factors in §F(2)(a) and (b) of this regulation. The criteria listed as factors in §F(2)(c)—(f) of this regulation are then considered. The lowest cost remedy which provides an acceptable balance of these four criteria may be selected. Types of costs that are considered within the factor in §F(2)(g) of this regulation include: Capital costs, including both direct and indirect costs; Annual operating and maintenance costs; and Net present value of capital and annual operating and maintenance costs. During remedy selection, comments from the county in which the site is located and comments from the public shall be considered to the extent practicable, and may be a modifying factor. The Department shall select the remedy. The Department may approve accelerated remediation, and may divide the site or remedial process into phases, upon a determination that: A portion of the remediation can be accomplished expeditiously; and The accelerated portion of the remediation would be consistent with the anticipated remedy for the entire site. Implementation of the Remedy. The remedial design/remedial action stage includes development of the design of the selected remedy and implementation of the remedy through construction. The Department may monitor or enforce compliance of the remedial action with cleanup standards and State or federal laws, regulations, and other requirements. Design and implementation of the remedy shall conform with the selected remedy. A period of operation and maintenance may follow installation of the remedy. Remediation may cease when, in the Department's judgment: Sufficient time has elapsed to ensure that contaminant levels have been reduced to levels that are protective of human health and the environment; or No detectable contamination remains at the site. If the Department determines that the selected remedy is not likely to be effective within a reasonable time, then the Department may require a reevaluation of the selection of remedy in accordance with §F of this regulation. Environment Article, §§4-405(a)(7), 7-208(e)(10), and 7-208(f), Annotated Code of Maryland Effective date: May 10, 1993 (20:9 Md. R. 781)