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Protection of Oregon's groundwater resources is critical to accommodate a growing population and to support the continued economic health of Oregon. Groundwater is a critical natural resource that provides Oregonians with water for drinking, agriculture, and industry. Almost half of the state's population (48 percent or 1.4 million people) is dependent upon groundwater for their daily needs, while 77 percent (or 2.3 million) of the state's population is at least partially dependent upon groundwater used at home, work, or school. This figure includes the larger metropolitan areas which use groundwater as a backup water supply.

There are approximately 3,450 public water systems in Oregon. Public water systems are defined as those having four or more service connections or are used by 10 or more individuals per day at least 60 days per year.

Recent inventory shows that 88 percent of Oregon's public water systems rely at least in part on groundwater for their source of supply (permanent or emergency). There are also an estimated 300,000 domestic wells in use in Oregon. According to the Water Resources Division (WRD), the demand for groundwater has doubled over the last 20 years, from 3.3 billion gallons per day to 7.0 billion gallons per day in 1990.

In Oregon, DEQ estimates that public water suppliers and industry use about 7 percent each of the resource, agriculture uses 75 percent for irrigation, and 11 percent is used for livestock watering and rural domestic uses. The majority of wells are in shallow, unconfined aquifers (under 200 feet deep) which are common to most of Oregon's valleys. Most of Oregon's existing developed areas and those likely to grow in the next 20 years are located over unconfined aquifers which are generally the most sensitive to pollution. These very vulnerable areas of Oregon's valleys (and alluvial sediments) are extensive. Efforts to protect groundwater at the local and state levels can be more efficiently directed if wellhead protection areas are known. This will allow us to focus our limited resources on priority areas first.

Domestic use is considered to be the use that requires the highest level of water quality and where potential groundwater pollution would have the greatest adverse impact on beneficial uses. Under current federal and state laws, assurances that public water systems meet drinking water standards are accomplished through monitoring and treatment. The Oregon Health Division (OHD) is responsible for administering both state and federal drinking water laws under ORS Chapter 448. This includes overseeing the sampling and analysis for over 100 different contaminants. The most current list of these contaminants, along with the maximum contaminant levels allowed by EPA, are provided in Table 1-1 Contaminants and Maximum Levels.

As of late 1995, OHD has reported detections of at least one of these contaminants in 383 (11%) of active public water systems in Oregon. In addition to this, there are approximately 50 individual public water systems which are currently threatened by groundwater contamination from active environmental cleanup sites in Oregon (DEQ, 1995).

Groundwater can become contaminated by many types of activities and land uses. Figure 1-1: Examples of Groundwater Contamination Sources illustrates some of the more common sources of groundwater contamination. Once any kind of contaminants enter the groundwater system, they can readily move with the normal flow of groundwater to reach a public water supply well.

When a public water system becomes contaminated, it is a very expensive and time-consuming process to address the problem. There are many direct costs associated with a loss of the public water system. Alternative drinking water supplies must be secured. Residents are often forced to buy and transport bottled water to their homes for daily water needs. The costs of replacing the contaminated water system or treating the existing one will generally result in substantial increases in the community's water rates. When a well becomes contaminated, this usually means the entire aquifer in that area is affected. There are costs associated with identifying and investigating the source of the contamination, as well as potential legal fees and consulting fees. Table 1-2 provides a summary of the costs associated with contamination response versus Wellhead Protection Plan development.

Table 1-2: Contamination Response vs. Wellhead Protection Plan Costs


1991-96 Actual Cost of Contamination Response to Detection of Trichloroethane in Drinking Water in a 300-Resident Oregon Community

Source Investigation/Sampling & Analysis $180,000

Water Treatment System Design & Installation

TOTAL $505,000

Typical Costs for Wellhead Protection Plan Development in a

Small Community


$ 500

Inventory of Sources

$ 1,500

Management Plan

$ 2,000

Contingency Preparation

$ 500

Report Preparation

$ 1,000
TOTAL $ 5,500*
* NOTE: DEQ and OHD estimate that Wellhead Protection costs for most large or small systems will average approximately $5/year/person, generally taking 2-3 years to complete.

There are also many indirect costs associated with the loss of a public water system. The unknown costs and timeframes for cleanup and/or treatment of the contaminated drinking water can result in lower property values and an inability to sell homes in the community. Perhaps the greatest indirect cost associated with any contamination detection is the local community's high level of concern regarding the potential health impacts of drinking the contaminated water.

Although the requirements for monitoring the public water systems in Oregon provide some degree of assurance of safe drinking water, all systems are vulnerable to potential contamination, limited reliabilities of sampling, and equipment failure or human errors that can occur during treatment. One of the best ways to ensure safe drinking water is to develop a program designed to protect against any potential contamination problems. This will provide another level of safety beyond the existing monitoring and treatment requirements.

Since groundwater supplies and conditions vary from one part of Oregon to another, the responsibility for protecting a community's groundwater rests substantially with the local jurisdictions. By working together, local jurisdictions and state agencies can implement custom-designed local wellhead protection plans to protect groundwater resources.


The federal Safe Drinking Water Act (SDWA) was initially adopted in 1974. Its primary purpose was to ensure that drinking water supplies do not adversely affect the health of the general public. The SDWA required that the Environmental Protection Agency (EPA) set standards for maximum contaminant levels in public water supplies delivered to any use. EPA had developed standards for 34 contaminants by 1986. Increased public concern about other potential contaminants in drinking water supplies led to amendments to the SDWA in 1986. The amendments required EPA to set maximum contaminant levels for 83 compounds and an additional 25 compounds every 3 years thereafter.

Subsection 1428 of the SDWA Amendments of 1986 also required that each state develop a wellhead protection program to "protect wellhead areas within their jurisdiction from contaminants which may have any adverse effect on the health of persons." Wellhead protection areas are defined in Section 1428 as the "surface and subsurface area surrounding a water well or wellfield, supplying a public water system, through which contaminants are reasonably likely to move toward and reach such water well or wellfield." Each individual state was to determine how the wellhead protection areas are delineated.

The SDWA specified that each state had to submit individual wellhead protection programs to EPA for approval. The SDWA provided great flexibility for states in establishing programs that suit local needs in protecting public water systems, but provided seven required elements. Section 1428 specified that each state program shall, at a minimum:

The overall structure of each state's wellhead protection program can be tailored to state-specific implementation issues. The way in which it is administered can also vary from state to state. Each state must, however, include in their program a process by which local entities can gain state approval of their plans. This will ensure that all local plans meet the requirements of the SDWA. A state approval of a local plan will also confer official recognition to the plan.

In implementing the SDWA, EPA has encouraged states to develop mandatory wellhead protection programs which would require protection of public water supplies in each state. Many states have chosen to develop voluntary wellhead protection programs instead of mandatory due to fiscal, political, administrative, or other reasons. EPA has specified several additional components that should be included in voluntary programs to compensate for potential lack of implementation since participation is not mandatory. In addition to the elements listed above, EPA expects the following also be included in each voluntary program:

As of May 1995, 39 states have received EPA approval of their programs. Eighteen of those are voluntary programs. One of the primary incentives for gaining EPA approval of a state wellhead protection program is the potential future availability of funds through the SDWA for wellhead protection. Only those states with approved programs will likely be eligible for any funding that may become available as a result of reauthorization of the SDWA.

The federal Safe Drinking

Water Act (SDWA)

was initially adopted in

1974. Its primary

purpose was to ensure that

drinking water supplies

do not adversely affect the health

of the general public.


In August 1986, the Department of Environmental Quality (DEQ) was officially designated by the Governor as the lead agency for development and implementation of Oregon's Wellhead Protection Program. Oregon's natural resource agencies developed and gained approval of a comprehensive groundwater protection plan called the Oregon Groundwater Act in 1989. Wellhead protection was considered an integral part of that statute. When funding became available for wellhead protection in 1990, DEQ and other state agencies initiated the process of developing a wellhead protection program which would have been mandatory for public water systems in Oregon.

DEQ, the Oregon Health Division (OHD), the Water Resources Department (WRD) and other state agencies joined with public citizens to form an advisory committee to develop Oregon's Wellhead Protection Program. The Wellhead Advisory Committee (WAC - members listed in Acknowledgments Section) consisted of representatives from large and small communities, public water systems, county planning, consulting, industry, agriculture and environmental communities. Over a period of 2 years, the WAC developed conceptual plans for a mandatory wellhead protection program in Oregon. Acknowledging budget limitations statewide, the original proposal for the mandatory program included a 10-year phase-in of wellhead protection plan initiation by the public water systems in Oregon. The larger systems were to initiate the development of a wellhead protection plan first, followed by smaller systems later on. New statutory authorities and agency funding were necessary for the development and implementation of a mandatory wellhead protection program. The DEQ and the WAC prepared a Public Advisory Plan (DEQ, 1992) to guide the implementation of the proposed mandatory program. However, the legislative proposal for the mandatory program failed to be approved in the 1993 session. The reasons for failure included the lack of state funding, concerns about increased land use controls, and local government's lack of resources to implement a mandatory program.

Wellhead protection plans were already being developed for Springfield, Boardman, Portland, Klamath Falls, and Medford. Many smaller public water systems and communities wanted to begin developing wellhead protection programs, but were concerned that there were no guarantees that any locally developed approach would address DEQ's future program requirements. DEQ recognized the need to establish a program and issue written guidance for wellhead protection, even if the most likely alternative for public acceptance was a voluntary program.

DEQ sought guidance in early 1994 from the Oregon Department of Justice (DOJ) in determining whether the existing statutory authorities for groundwater protection gave state agencies the ability to develop a voluntary wellhead protection program. The DOJ clarified that DEQ did have the statutory authority to institute a voluntary wellhead protection program, as long as local government participation is completely nonmandatory.

Statutory Authorities

Department of Environmental Quality (DEQ):

Both the statutory provisions describing DEQ's general functions and those for groundwater protection provide a broad authority that would allow DEQ to institute a nonmandatory wellhead protection program. As part of its departmental functions, state statutes require that DEQ:

"(a)Shall encourage voluntary cooperation by the people, municipalities, counties, industries, agriculture, and other pursuits, in restoring and preserving the quality of the air and the waters of the state in accordance with the rules and standards established by the commission.

"(b)May conduct and prepare, dependently or in cooperation with others,...programs pertaining to the quality and purity of the air or the waters of the state....

"(e)Shall conduct and supervise programs of air and water pollution control education, including the preparation and distribution of information regarding air and water pollution sources and control...

"(g)Shall develop and conduct demonstration programs in cooperation with units of local government...

"(L)Shall encourage the formulation and execution of plans in conjunction with ... associations of counties, cities, industries and other persons who severally or jointly are or may be the source of air or water pollution, for the prevention and abatement of pollution."

ORS 468.035

DEQ thus has broad authority to institute programs and to work with units of local government to abate and prevent water pollution, especially when such programs can be considered educational or demonstrative. Moreover, the Legislative Assembly's policies mandate that:

"Programs to prevent ground water quality degradation through the use of the best practicable management practices shall be established."

ORS 468B.160(4)

DEQ also administers the state's water pollution control statutes which include provisions for protection of groundwater. The legislature has specified that a primary goal of the water pollution control statutes is to protect groundwater from contamination:

"The Legislative Assembly declares that it is the goal of the people of the State of Oregon to prevent contamination of Oregon's ground water resource ..." ORS 468.692

Under ORS 468.693 it is the state's policy to provide for:

DEQ's pollution control statutes allow the agency to set standards and regulations governing the discharge of contaminants to groundwater and also provide the agency authority to take action where contamination of a groundwater source has occurred. This authority is implemented through OAR 340-40-001, et seq. Under ORS 468(B).175, DEQ has authority to make a declaration of an area of groundwater concern where it finds contaminants exceed certain specified threshold levels due at least in part to nonpoint sources. This authority is overlapping with that of the Health Division. DEQ also has the authority under ORS 468(B).180 to make a declaration of a groundwater management area where it finds contamination above specified regulatory threshold levels.

None of the above mentioned statutes are structured to provide authority for DEQ to mandate or enforce local government participation in a wellhead protection program. None of those statutes provide authority for DEQ to have direct control of land usage within protection areas either. However, DEQ clearly has the authority to institute a nonmandatory wellhead protection program because such a program:

Oregon Health Division (OHD):

OHD administers the Oregon Drinking Water Quality Act (ORS 448.119 through 448.285 and 454.235, 454.255 and 757.005). It is the primary authority applicable to public water systems in Oregon.

OHD adopts water quality standards, construction standards, operation standards, and other standards and requirements considered necessary by the Division to insure safe drinking water and to implement the federal Safe Drinking Water Act (ORS 448.131). OHD administers and oversees all sampling and analyses of drinking water in Oregon.

OHD regulations have applied to construction of new public water systems and to major additions or modifications to existing systems since around 1980. OAR 333-61-050 et seq. These regulations require detailed site plans for approval of wells to serve public water systems using groundwater (OAR 333-61-060). In effect, OHD's current regulations require a de facto wellhead protection area (ownership of the land by the water supplier is required) of 100 ft. radius (subject to variance or approval of OHD) for confined wells and similar or more restrictive criteria for unconfined public supply wells (OAR 333-61-050(2)). The site plans must also identify sanitary hazards, reserved areas to be kept free of contamination sources and evidence of control of the reserve areas.

OHD's regulations also require public water suppliers to provide comprehensive monitoring and testing of groundwater quality and may require that the system provide alternative supplies where contaminant levels are exceeded (OAR 333-61-045).

OHD also has the authority and responsibility to declare an area of groundwater concern if it confirms the presence in groundwater drinking water supplies of contaminants resulting at least in part from suspected nonpoint source activities above certain specified levels (ORS 448.268). This declaration can lead to comprehensive management strategies (it has the responsibility to notify the DEQ of a potential groundwater management area if it detects contaminants above certain specified threshold levels) but the authority is remedial in nature and not of a preventative type as required by a wellhead protection program.

While OHD has fairly comprehensive authority over public water supply systems, its authority does not extend beyond those systems in a manner which might be necessary to require the development and implementation of a comprehensive wellhead protection program by local governments. OHD's statutory authorities and responsibilities most directly applied to three specific elements of Oregon's wellhead protection program - the delineation, contingency, and new wells elements. OHD's role in implementing Oregon's Wellhead Protection Program will be discussed in more detail in Section 1.4 (Overview of Implementation).

After evaluating the statutory authorities and alternative approaches to develop a wellhead protection program, DEQ, OHD, and the citizens advisory committee members agreed to move forward with an effort to increase public education about wellhead protection and develop rules and a guidance manual to implement a voluntary wellhead protection program.

The first step in developing Oregon's voluntary Wellhead Protection Program was to form a new public advisory committee.

The first step in developing Oregon's voluntary Wellhead Protection Program was to form a new public advisory committee. The "Wellhead Rules and Guidance Committee" (WRGC) is made up of several members of past advisory committee, as well as new members from various interest groups and government agencies from throughout Oregon. WRGC met monthly for a year, providing valuable input and ideas as DEQ and OHD drafted this guidance manual and accompanying rules.


This section provides an overview of how Oregon's Wellhead Protection Program will be implemented at both the state and local levels. The Oregon DEQ will administer the program and be responsible for ensuring implementation and reporting to EPA. There will be significant involvement from other state agencies as well. The Oregon Health Division (OHD) will be responsible for providing technical assistance, review, and approval for the delineation, contingency, and new wells elements of wellhead protection. DEQ is responsible for all other elements in the process, including the final certification of the local community plans. The Oregon Department of Agriculture (ODA) will provide significant input for development of management approaches for agricultural lands within wellhead protection areas. The Water Resources Department (WRD) and the Department of Ecology and Mineral Industries (DOGAMI) will provide technical assistance and input as needed during the delineation, contingency, and new well element reviews. All agency reviews and "sign-offs" will be coordinated through DEQ. This will enable a more streamlined approach for the local communities.

How Do We Develop a Wellhead Protection Plan?

DEQ and OHD are hopeful that the demand for technical assistance and review of Wellhead Protection Plans will continue to be high. If the demand exceeds existing staff resources, DEQ and OHD will prioritize individual requests based primarily upon the level of threats to groundwater quality within close proximity to the well. DEQ and OHD staff will determine this relative level of threat using the information presented by the community when the request is made. DEQ and OHD will meet regularly with other agencies and individuals to ensure smooth implementation of the program.

A wellhead protection effort can be initiated by any "Responsible Management Authority" (RMA) seeking to develop a Wellhead Protection Plan for their local area. The RMA could be any or all of the following:

With the assistance of the Wellhead Rules and Guidance Committee, DEQ has developed a descriptive process for a local community to implement wellhead protection. The process is shown on Figure 1-2 as a sequence of "steps". The following steps will be described in detail in Section 3 of this Guidance Manual:

Step 1: The RMA contacts DEQ or OHD and sets up workshop or meeting for an introduction to wellhead protection.

[OPTIONAL - RMA can create a "Pre-Plan Assessment" of potential threats to drinking water in nearby vicinity or well and use it to raise awareness for the need to protect the drinking water supply.]

Step 2: RMA identifies/cooperates with other RMAs and assembles a Local WHP Advisory Team (Team) to include representatives from the various interests and local communities potentially affected by the Wellhead Protection Plan.

It is recommended at this point in the process that the local community, through the Team, determines if they want to ultimately gain state certification of their Plan. If the intent is to gain state certification, it is very important to contact and work with the Oregon Health Division (OHD) during the next step.

Step 3: RMA(s) or consultant conducts DELINEATION of WHP area and gains sign-off from OHD (OHD consults with other agencies, as appropriate).

Step 4: Team solicits volunteers as necessary and performs INVENTORY using technical assistance from DEQ.

Step 5: Team develops the management approach using technical assistance from DEQ.

[OPTIONAL - RMA(s)/consultant can conduct a "Use and Susceptibility Assessment" per OHD guidance.]

Step 6: RMA(s) develop a CONTINGENCY PLAN using technical assistance from OHD.

Step 7: RMA(s) develop a plan describing procedures for any future NEW WELLS (due to growth or loss) using technical assistance from OHD and WRD.

Step 8: RMA(s) assemble and submit a written Plan of action and obtain certification from DEQ.

Figure 1-2: Overview of Implementation

Wellhead Protection Process Diagram

The written Plan or Report will document each element, public participation efforts, and implementation of management approach, updates, etc.

The primary purpose of this guidance manual is to explain how to move through these eight steps to accomplish wellhead protection in your local area. Section 3 will describe each of these steps in detail and provide additional resources and references for assistance with the process. It is critical to involve the public in wellhead protection efforts at the initiation step of the process, as well as throughout the process.

What Are The Incentives for State Certification?

Local jurisdictions or RMAs that develop Wellhead Protection Plans can elect to submit the Plan for state approval or "certification". Gaining certification of a Plan is not required, although there are some direct benefits for obtaining state certification. Four of the most significant incentives for state certification include:


Oregon's wellhead protection program will primarily be implemented by Oregon DEQ, but with significant input and involvement from other agencies. Local jurisdictions or Responsible Management Authorities (RMAs) obviously also play an extremely important role in accomplishing wellhead protection.

Oregon's wellhead protection

program will primarily be

implemented by the

Department of Environmental Quality (DEQ)

and the

Oregon Health Division


A more detailed list of specific responsibilities for each state agency or other entity follows:

Department of Environmental Quality (DEQ)

Oregon Health Division (OHD)

Water Resources Department (WRD)

Department of Land Conservation and Development (DLCD)

Department of Ariculture (ODA)

Department of Economic Development (DED)

Department of Transportation (DOT)

Oregon State Fire Marshal (SFM)

Responsible Management Authorities (RMA)


Many cross-jurisdictional issues may arise as wellhead protection areas are delineated. The wellhead protection area may not be entirely within your jurisdiction, city limits, or property boundaries. This section will discuss how to address issues concerning cooperation from your neighboring jurisdictions.

It is very important to involve as many as possible of the jurisdictions in your local area as you begin developing a Wellhead Protection Plan. If the neighboring jurisdiction also has a groundwater-supplied public water system, one of the primary incentives for them to become involved in your community's efforts is that it would be cost-effective to combine your resources and delineate more than one wellhead protection area at a time. This regional approach could be facilitated by the county, for example, or a committee representing all participating jurisdictions. Efforts to reduce the risk of contamination of the public water systems are generally easier by developing a coordinated regional approach and combining resources to implement your Plan(s). The Department of Environmental Quality and the Oregon Health Division are available to assist in local efforts to combine wellhead protection efforts. The results can be submitted as individual Plans or as a combined Plan. The agencies will evaluate the delineation and other elements of a combined Plan with the same criteria as for an individual Plan, using the resources and information contained in this manual as a guideline.

In the event that your neighboring jurisdiction has no groundwater-supplied public water system, you should still ask for their involvement, especially if part of your wellhead protection area is located within their jurisdiction. Ideally the neighboring jurisdiction(s) will be willing to participate in protecting your public water supply since this will benefit the surrounding area as well (see Section 1.1 for a discussion of the benefits). Although the staff resources may not be available for them to participate in the actual development of your Plan, the most important contribution from them will be to become a "signatory" to your Plan. Becoming a signatory to your Wellhead Protection Plan means that neighboring jurisdiction(s) will help facilitate the implementation of your Plan within their city limit or jurisdictional boundaries (this could include the county). The level of involvement on their part will depend upon the number and types of potential contamination sources within the wellhead protection area in their jurisdiction and the particular types of management approaches selected by your community (preferably with their input) for those potential sources. Example activities might involve helping to coordinate events such as household hazardous waste collections, spill response planning, and facilitating local educational workshops or installation of signs to raise public awareness of the location of the wellhead protection area boundary.

In some cases, a neighboring jurisdiction(s) will not be cooperative and will refuse to participate in the development, or refuse to become a signatory to, your Wellhead Protection Plan. One of the most effective ways to resolve the issue will be to ask your county officials for assistance. This should be your first priority in seeking a resolution for any cross-jurisdictional conflicts, as these solutions are generally more easily and effectively accomplished at the local level. This could be done by developing a "Memo of Understanding" between the affected jurisdictions. The DEQ Wellhead Protection Program staff can also be consulted for assistance in resolving the issue informally. DEQ will use any available state or federal (tribal commissions, etc.) resources to help facilitate a resolution to this issue. Since this is a voluntary program, there is no mechanism for DEQ to require another jurisdiction to participate or become a signatory to your Wellhead Protection Plan.

The only state agency in Oregon with current authority to require any kind of participation in a wellhead protection effort is the Department of Land, Conservation, and Development (DLCD). DLCD administers the Oregon Statewide Planning Goals. Under the existing rules, when the "location, quality, and quantity" of a groundwater resource is identified, the area becomes a "Goal 5 Resource". Under the existing rules, this includes any wellhead protection area that is delineated. DLCD has proposed (as of 4/96) to modify these rules and exempt most of the wellhead protection areas in Oregon from any Goal 5 requirements. Only the wellhead protection areas of public water systems serving more than 10,000 people or have more than 3,000 service connections will now be affected by Goal 5 requirements. There are currently 26 communities in Oregon that meet these criteria.

Under the new proposed (as of 4/96) rules, if your jurisdiction has a public water system that serves greater than 10,000 people or has more than 3,000 service connections and the local government chooses to delineate the wellhead protection area, the Goal 5 Resource element in Oregon's Statewide Planning Program could be used to ensure your public water supply is also protected by neighboring jurisdictions. A wellhead protection area in these larger communities in Oregon becomes a Goal 5 resource when the voluntary delineation is certified by the Oregon Health Division. Once a Goal 5 resource is identified under Oregon's planning program, local jurisdictions must take steps to protect it.

A DEQ-certified Wellhead Protection Plan will automatically serve to address any Goal 5 requirements for protecting these groundwater resources. Once a wellhead protection area delineation is certified

by the Oregon Health Division in one of the larger communities in Oregon, the neighboring jurisdictions will be required to participate in the development of or become a signatory to your Wellhead Protection Plan. More information about Goal 5 planning requirements and wellhead protection can be obtained by calling DLCD at 503-373-0083 (see also Section 3.5.1).

Documentation of your efforts to secure the participation of neighboring jurisdictions should be a part of your Wellhead Protection Plan report. If good faith efforts (on all levels) are made and are unsuccessful, DEQ will still evaluate and potentially certify your Plan if at least 70 percent of the delineated wellhead protection area is within the jurisdiction of the

signatories to your Plan. DEQ will evaluate these "70 to 99 percent Coverage" Plans based on the same criteria used for the others. Keep in mind that the single most important factor in the certification of a Wellhead Protection Plan will be whether there is a significant reduction in the risk of contamination to your public water system. Depending on the management approaches selected by the local community, one can very easily choose protective tools for that 70 percent of the wellhead protection area that are more effective than others managing the entire wellhead protection area. DEQ will consider these issues, as well as the non-cooperative jurisdiction's potential sources and proximity to the supply well in evaluating whether to certify the Plan.

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