Ariz. Admin. Code § R18-16-406 - Remedial Investigations

A. The remedial investigation for a site or portion of a site shall:

1. Establish the nature and extent of the contamination and the sources thereof,

2. Identify current and potential impacts to public health, welfare, and the environment,

3. Identify current and reasonably foreseeable uses of land and waters of the state, and

4. Obtain and evaluate any other information necessary for identification and comparison of alternative remedial actions.

B. The Department or any person may perform all or any portion of a remedial investigation, except that once the Department has issued a notice under A.R.S. § 49-287.03 for a site, a person may perform such work only under a written agreement with the Department. A work plan shall be developed and implemented for all or any portion of a remedial investigation for a site or a portion of the site, as follows:

1. The work plan shall demonstrate that the work performed will meet the requirements of subsections (C) and (D) and that the work will be performed in accordance with guidance documents issued by the Department or standards or other guidance documents that are commonly accepted in the scientific community. Standards or guidance documents are considered to be commonly accepted in the scientific community if they are published in peer-reviewed literature such as a professional journal or publication of standards of general circulation, and if there is general consensus within the scientific community about the guidance document or standard.

2. Each work plan shall include the following elements:

a. A description of the work, including any community involvement activities to satisfy any applicable requirements of R18-16-403 or R18-16-404, a statement of justification for the work, and a plan for conducting the work;

b. A quality assurance project plan;

c. A site location map;

d. A schedule;

e. A health and safety plan consistent with 29 CFR 1910.120; and

f. A sampling and analysis plan.

3. A work plan may be modified as work proceeds to address unknown or changed conditions or access problems.

4. Any person proposing to implement a work plan for all or a portion of a remedial investigation shall, before implementing the work plan, notify the Department in writing of the name and address of the working party and a general description of the work being performed. This notice is for the Department's information only and receipt of the notice shall not constitute approval of the work plan. A person seeking approval of a work plan by the Department shall submit a written request under R18-16-413.

C. The remedial investigation, which may be conducted in one or more phases to focus sampling efforts and increase the efficiency of the investigation, shall include field investigations to assess the following factors:

1. Physical characteristics of the site, including important surface features, soils, geology, hydrogeology, meteorology, and ecology;

2. The extent and general characteristics of the hazardous substances released, including physical state, concentration, toxicity, propensity to bioaccumulate, persistence, and mobility;

3. The extent, general characteristics, and degree of the source of the release;

4. Current and reasonably foreseeable exposure routes for the hazardous substances released, such as inhalation, ingestion and dermal;

5. Other factors, such as sensitive populations, that pertain to the characterization of the site or support the analysis of potential remedies; and

6. Current and reasonably foreseeable impacts to aquatic and terrestrial biota.

D. The remedial investigation shall include the collection of information regarding current and reasonably foreseeable uses of land or of waters of the state that have been or are threatened to be impacted by the release, and projected time-frames for future changes in those uses. Reasonably foreseeable uses of land are those uses of land likely to occur at the site. Reasonably foreseeable uses of water are those likely to occur within 100 years unless a longer time period is shown to be reasonable based on site-specific circumstances. Information may be solicited from any interested person including any known well owner. Information collected shall include:

1. Information regarding current and reasonably foreseeable uses of water for each aquifer that is impacted or threatened to be impacted by the release, considering any hydraulic connection between aquifers. The information shall include the locations and uses of existing wells, including all wells already impaired due to contamination, the locations and uses, if known, of any planned wells, and any written water management plans used by water providers whose water supplies may be impacted by the release. This information shall be collected in consultation with affected water providers.

2. Information regarding current and reasonably foreseeable uses of water for each segment of surface water impacted or threatened to be impacted by the release. This information shall be collected in consultation with affected water providers.

3. Information regarding current and reasonably foreseeable uses of land impacted or threatened to be impacted by the release within the community involvement area. General land use information shall include the current type of use, density, character, and governmental jurisdictions. Future land use changes shall be considered using population projections, growth, plans for future development and local land use plans. This information shall be collected in consultation with local governments with land use jurisdiction. The information collected shall also include specific land uses and property ownership for properties where the land use is impacted or threatened to be impacted by the release.

E. Using the data developed during the field investigation and information collected concerning uses of land and of waters of the state, a site-specific risk evaluation may be conducted to characterize the current risks to public health and the environment from contaminants of concern.

F. Following the collection of data necessary to adequately characterize the site or portion of the site and the collection of information necessary to determine the uses of land and of waters of the state, a draft remedial investigation report shall be prepared, and if prepared by a person other than the Department, submitted to the Department. The draft remedial investigation report shall include the results of any risk evaluation conducted under subsection (E). The draft remedial investigation report may consist of a summary of the data and information collected with references to the supporting documentation and the location of the public repository where those documents may be reviewed. Copies of the draft remedial investigation report prepared by or approved for release by the Department shall be provided to the community advisory board, interested local government agencies, affected water providers, and the Department of Water Resources. Copies of the draft remedial investigation report also shall be made available to the community under the community involvement plan. Public notice shall be given of the opportunity to comment on the draft remedial investigation report. This notice may be combined with the notice given under subsection (I)(1).

G. For remedial objectives used to select a soil remediation remedy, the landowner has the right to identify the type of land use in accordance with A.R.S. § 49-152 and 18 A.A.C. 7, Article 2. If the remedy for the site or portion of a site will address landfill or other non-soil materials other than waters of the state, the landowner may establish the current and reasonably foreseeable uses of its land provided that the remedial objectives for the site are not required to address land uses impaired by properties of materials located on or under the land other than the current or potential exposure to the hazardous substances contained in that material.

H. If the remedy for the site or a portion of the site will not address waters of the state, a final remedial investigation report may be prepared containing the results of the site characterization and a listing of remedial objectives. The remedial objectives shall be based on the current and reasonably foreseeable uses of the property in accordance with subsection (G) and stated in accordance with subsection (I)(4). The report shall be accompanied by responsiveness summaries regarding comments, issues, and concerns regarding the draft remedial investigation report under subsection (F), and if the report is prepared by a person other than the Department, copies of the comments received. The report may be submitted to the Department for review under R18-16-413 . If the Department approves the report, the procedures in subsections (I) and (J) do not apply, and the approved report may be used to select a remedy under R18-16-407(C) or R18-16-407(D) . Notice of the availability of the final remedial investigation report shall be provided with the notice under R18-16-408(C).

I. Except as provided in subsection (H), remedial objectives shall be developed as follows:

1. After the draft remedial investigation report is made available, the Department shall hold 1 or more public meetings to obtain information for purposes of establishing remedial objectives for the site. The Department shall provide notice of the public meeting. If a community advisory board has been formed for the site, public meeting arrangements shall be coordinated with the community advisory board. The initial public meeting shall be held not less than 45 calendar days and not more than 90 calendar days after release of the draft remedial investigation report, unless the Department sets a different date for good cause.

2. At the public meeting, the Department shall solicit and consider proposed remedial objectives for the site. The Department also may receive and consider written information regarding proposed remedial objectives.

3. Remedial objectives shall be generally consistent with the water management plans of all water providers whose water supplies are or may be impaired by the contamination and with the general land use plan established by the local land use jurisdiction.

4. The Department shall prepare a report of the proposed remedial objectives for the site that shall list the current and reasonably foreseeable uses of land and the current and reasonably foreseeable beneficial uses of waters of the state. These uses shall be identified based upon information provided during the public meeting and any other information received. The report shall state the remedial objectives for each listed use in the following terms:

a. Protecting against the loss or impairment of each listed use that is threatened to be lost or impaired as a result of a release of a hazardous substance;

b. Restoring, replacing or otherwise providing for each listed use to the extent that it has been or will be lost or impaired as a result of a release of a hazardous substance;

c. Time-frames when action is needed to protect against or provide for the impairment or loss of the use; and

d. The projected duration of the action needed to protect or provide for the use.

5. The Department shall provide notice and accept and consider public comment on the proposed remedial objectives in the remedial objectives report and shall hold at least 1 additional public meeting if significant public interest exists or if significant issues or information have been brought to the attention of the Department which have not been considered previously.

6. The Department shall prepare a final remedial objectives report.

J. Following the community involvement activities regarding the draft remedial investigation report and the remedial objectives report, a final remedial investigation report shall be prepared containing the results of the site characterization and the final remedial objectives report. The final remedial investigation report shall be accompanied by responsiveness summaries regarding comments, issues and concerns raised in the community involvement process and, if the report is prepared by a person other than the Department, copies of the comments received. After completion of the final remedial investigation report, changes to the remedial objectives are subject to the requirements of subsection (I). The Department shall provide notice of the availability of the final remedial investigation report.

K. Any person, other than a person proposing to perform work under an agreement under A.R.S. § 49-287.03(C), may submit a request under R18-16-413 for the Department to approve a work plan or a report for all or any portion of a remedial investigation. The Department shall approve a work plan for a remedial investigation if the request shows that the work will comply with this Section, community involvement activities will comply with R18-16-404, and the work plan provides for modifications to address unknown or changed conditions or access problems. The Department shall approve a draft remedial investigation report if the work is in compliance with an approved work plan or, if no work plan was approved, the remedial investigation complies with this Section and the community involvement activities have been conducted under this Article.

Notes

Ariz. Admin. Code § R18-16-406

New Section made by exempt rulemaking at 8 A.A.R. 1491, effective March 4, 2002 (Supp. 02-1).