Chapter 6 - Historical Archaeological Resources: Evaluation and Treatment

This chapter presents Caltrans' policies and procedures for evaluating and treating historical archaeological resources, including sites and districts composed of historical archaeological sites. In California, the historic era generally is defined as the period following initial Euro-American exploration in the region and establishment of the first Spanish mission in 1769. Sites, as used in this chapter, specifically encompass both historical archaeological sites and those places identified as Traditional Cultural Properties (TCPs). These procedures have been developed to comply with Section 106 of the National Historic Preservation Act of 1966, as amended, and the provisions of the Section 106 Programmatic Agreement (Section 106 PA). The same general process is also used for compliance with the California Environmental Quality Act (CEQA).

For federally assisted state and local projects, as well as state-only projects, there are two types of reports that are used to document historical archaeological resources:

1) The Letter Report is to be used only when the provisions of the Section 106 PA do not apply, such as for projects involving tribal land or state-only funds. It is used to document cultural resources that have no potential for meeting the eligibility criteria for inclusion in the National Register of Historic Places (see Section 6-5 and Exhibit 6.1). The Letter Report is attached to the project’s Historic Property Report (HPSR), or for state-only projects, the Historical Resources Compliance Report (HRCR).

2) The Historical Resources Evaluation Report (HRER) is used to document evaluations of all types of historical archaeological resources. Section 6-10 and Exhibit 6.2 contain detailed instructions for completing an HRER. Caltrans sends the HRER to SHPO as an attachment to the HPSR Section 106 consultation package (see Chapter 2 for guidance on preparing an HPSR and SHPO consultation). For state-only projects, the HRER is attached to the HRCR.

When archaeological excavation is required to identify or evaluate a site, the historical archaeologist prepares a proposal for an Extended Phase I (XPI) or a Phase II excavation (See Exhibits 5.2 and 5.4). Prior to implementation, a historical archaeologist who is qualified at the Principal Investigator level peer reviews the document (peer review procedures are discussed more fully below and in Section 6-16). The XPI and Phase II proposals are in-house documents used to guide Caltrans activities. The historical archaeologist reports the results of excavation and, if appropriate, site evaluation, in the HRER. Caltrans uses other report formats to plan for data recovery or post-review discoveries and to report the results of data recovery (Phase III) studies.

This chapter builds on the guidance contained in Chapter 5 on general archaeological studies. It begins by discussing the qualifications needed to evaluate different types of historical archaeological resources. Subsequent sections then discuss the evaluation process for historical archaeological resources that do not require excavation, the evaluation process for historical archaeological resources requiring excavation, the preparation of HRERs, treatment procedures necessary to complete the Section 106 process, and compliance procedures for state-only projects.

Qualifications required for evaluation and treatment of historical archaeological properties are dependent on the nature of the resources present. Multi-disciplinary teams may be necessary. See Chapter 1 Section 1-3.4 and Section 106 PA Attachment 1 for a discussion of minimum standards and guidelines, as well as certification levels under the Section 106 PA. Under the Section 106 PA, staff must meet the minimum qualification levels for Co-Principal Investigator (Co-PI) or Principal Investigator (PI) to evaluate historical archaeological sites. Exhibit 1.5 Table 1 describes the PQS levels required to perform archaeological activities and Table 2 describes PQS levels to complete the accompanying studies and construction monitoring. Note that a Caltrans PQS at the Principal Investigator (PI) level for historical archeology must peer review all historical archaeological work completed under the terms of the Section 106 PA.

Certification as a Caltrans PQS for Principal Investigator (PI) historical archaeologist is generally required to assume lead responsibility for evaluating historical archaeological sites. PI-level prehistoric archaeologists may also evaluate historic-era Native American archaeological sites. Co-PI-level historical archaeologists, under the direction of a PI-level historical archaeologist, may evaluate historical archaeological sites that do not require excavation (See Exhibit 1.5 Table 1).

Caltrans PQS in architectural history and consultants meeting the same qualifications (see Section 106 PA Attachment 1) often are trained in historical research, may provide valuable assistance with background research for evaluations of historic-era archaeological sites, and may need to be consulted prior to evaluating these resources. An interdisciplinary team including qualified architectural historians and historical archaeologists collaboratively should evaluate resources with both built and historical archaeological elements, as well as other types of cultural resources such as ruins of buildings and structures, cultural landscapes, battlefields, cemeteries, and the locations of important events. In addition, professionals with knowledge of cultural geography, the history of technology, folklore, and social history, to name a few, also may add valuable insights to understanding material culture. Sometimes this expertise is best obtained via consultant contract. . See Chapter 4 Section 4-4.2 and discussion of specific resources in Chapter 7, particularly Sections 7-4 and 7-8.5. Teams may be created from a combination of District Caltrans PQS, Headquarters PQS, or appropriately qualified consultants. Send requests for assistance from Headquarters staff to the Chief of the Cultural and Community Studies Office (CCSO).

The amount and types of information needed to complete the evaluation of a historical archaeological site will depend on the type of resource, its integrity, and the quality of available information about it. Caltrans PQS will determine when to contact the appropriate Information Center for a records search and will specify the level of information needed. Local agencies should be advised not to order record searches unless Caltrans PQS determine it necessary.

Historical archaeological resources that meet the criteria for “Properties Exempt from Evaluation” in Section 106 PA Attachment 4 clearly have no potential to be eligible for the National Register of Historic Places (National Register) and need not be evaluated. Only appropriately qualified Caltrans PQS or similarly qualified consultants may exempt such properties, as outlined in Attachment 4. The information gathered during the identification phase may sometimes be sufficient to make such summary conclusions without further research. Exhibit 4.1 contains guidance on sources of information. [In special circumstances, such as on tribal lands where the Section 106 PA does not apply but there are resources that meet the criteria for exempt properties as outlined in Section 106 PA Attachment 4, appropriately qualified Caltrans PQS or consultants may address such properties in a Letter Report. Section 6-5 and Exhibit 6.1 contain guidance on using Letter Reports.] All other historical archaeological resource evaluations should be documented in an HRER (see Section 6-10).

Information gathered as a result of identification activities such as background research, reconnaissance survey, and archaeological survey will usually need to be supplemented with additional research in order to complete evaluations of all but the most compromised resources. Additional historical research, interviews with knowledgeable individuals, or limited archaeological excavation, depending on the nature and complexity of the resource and the quality of available historical information, also may be necessary. Because of the expense and time involved in archaeological excavations, testing is normally undertaken only when there is a clear potential that the work will yield important information.

The nature of the resource, amount and quality of available documentary information, and current research issues will determine whether archaeological excavation may be appropriate and necessary. When archaeological excavation is conducted to determine site boundaries (e.g., Extended Phase I studies) or complete an evaluation (e.g., Phase II studies), historical archaeologists prepare an HRER according to the instructions provided in Exhibit 6.2. Staff should also take into consideration the content guidance offered in Chapter 5 and Exhibits 5.2 (XPI proposal), 5.4 (AER/Phase II proposal), 5.6 (DRP Phase III), 5.7 (DRP Phase III proposal), and 5.8 (DRP Phase III proposal).

The likely areas of significance of a historical archaeological resource and its physical condition guide the amount and depth of historical research needed. It is important to develop the proper historic context and to identify the site-specific data that allow its placement within that context. Background research also involves consideration of the scope and findings of previous research on similar types of sites. Historical archaeologists use all of this information to develop important research themes and specific questions within a regional or theoretical context and to identify data requirements that can be used to measure the significance of resources.

Historical research may be conducted in collaboration with historians and architectural historians, as described elsewhere in the chapter. When conducting historical research:

• Begin by using secondary sources to develop a general context for the project area. Secondary sources may help focus the research effort by revealing useful sources of information, informants, and other details.
• Next, use primary sources, as needed, to develop suitable contextual and site-specific details.

Refer to Exhibit 4.1 and Chapter 7 Section 7-6.2 for information on sources of information.

Gathering property-specific information will usually entail some use of primary sources. The depth of research conducted in primary records will depend on the particular values a historical archaeological resource is likely to possess and the availability of secondary information about it. Some primary sources such as Caltrans “as-built” plans; U.S. Bureau of Land Management land status, mining, and old Government Land Office survey plats and notes; and historic U.S. Geological Survey quadrangle maps already should have been consulted during the identification phase discussed in Chapter 4 Sections 4-4 and 4-5 and Exhibit 4.1. CCSO staff in Headquarters can provide assistance regarding information sources located in Sacramento, such as the California State Library and California State Archives.

Developing the Historical Overview

Site-Specific Discussion

Interviews

Develop research issues to determine whether the historical archaeological resource may have the potential to yield important information as required in National Register Criterion D. When developing the research issues, survey previous research concerning the type of property in question and formulate important themes or topics that the site might reasonably address and that cannot be addressed through historical research alone. The discussion should clearly explain which research themes and topics are important, why and how they are important, and how information contained within the archaeological site will illuminate and advance in specific ways our knowledge and understanding of historic themes or topics deemed significant. There should be some realistic potential to address any questions posed at the sites under investigation. Clearly defined data requirements should be the basis for assessing the potential value of any remains discovered at the property. Detailed knowledge of the social context and history of a resource is usually required to formulate research issues for historic-era occupation sites.

A historical archaeological site located within the project APE and which cannot be avoided by the proposed project must be evaluated if it is not otherwise exempt from evaluation. Additionally, such resources are often evaluated even when avoidance is possible in order to determine whether the effort and cost of avoidance is justified.

When evaluation is warranted, historical archaeological resources may be determined eligible for inclusion in the National Register under any of the four eligibility criteria, but most likely under Criterion D. See Exhibit 4.2 and National Register Bulletin 15 for guidance on applying the National Register criteria to the kinds of resources covered in this chapter. For CEQA purposes and when warranted, historical archaeological resources are simultaneously evaluated to determine whether they are historical resources for the purposes of CEQA.

How a historical archaeological site reflects any or all of the National Register criteria is determined by developing the appropriate historic contexts that seek to explain the importance of a property or group of related properties through knowledge of their historical circumstances. Historic contexts identify the period of significance, geographic scope, and historical themes that are used to assess the importance of particular types of properties. Context development should be sufficiently broad to address all potential areas of historical significance defined in the National Register criteria. However, the themes developed in a historical context should concentrate on the essential physical features or important information a resource is most likely to possess.

Evaluations of historical archaeological resources require a closely integrated assessment of both physical and historical evidence, thus a physical inspection of the property should be conducted early in the evaluation process before investing too much effort in historical research

The effort spent on historical research and the assessment of physical remains should be sufficient to fully substantiate the findings of the evaluation effort, while remaining commensurate with the condition (integrity) of the site. For sites with severely compromised integrity, limit the research to gathering basic facts that will support a finding that the resource is not eligible. Always give reasonable consideration to the potential for concealed or buried historical archaeological deposits, even in cases where little surface evidence is discovered during an archaeological reconnaissance survey.

National Register Criteria A, B, or C

National Register Criterion D

Under the Section 106 PA, Caltrans, FHWA, and SHPO have identified certain classes of properties that do not require recordation or evaluation (see Chapter 4 Section 4-4.1). Exempt archaeological properties, listed in Section 106 PA Attachment 4, typically do not warrant any identification, recordation, or evaluation effort. Only Caltrans PQS and consultants meeting the PQS criteria may exempt the properties.

Included in the list is the property type “isolated refuse dumps and scatters over 50 years old that lack specific associations” that deserves some special guidance. Application of Section 106 PA Attachment 4 for exemption of this class of resource must be conducted with care. There might be research values (potential to yield significant information) under National Register Criterion D that may not be readily apparent. In situations where the potential for historical association (or lack thereof) is not directly evident, contact a qualified Caltrans historical archaeologist to discuss the property. The Caltrans historical archaeologist will then offer guidance on appropriate level of research to determine whether the property meets the exemption criteria. If the research indicates some association, such as historical occupation of the parcel where the refuse scatter is located that corresponds to the date of the assemblage, the property is not exempt and will need to be evaluated. Where no association is present, the archaeological site will meet the requirements of Attachment 4. Archaeologists may record a historical archaeological site during the identification phase that may later be found to meet the requirements for exempt properties in Attachment 4. In this situation, edit the ASR or HPSR to indicate an appropriately qualified Caltrans PQS or consultant determined the recorded property exempt from evaluation.

The key to successful implementation of Section 106 PA Attachment 4 is sound professional judgment. Questions concerning the applicability of Attachment 4 to specific historical archaeological resources should be referred to the CCSO Section 106/PA Coordination Branch Chief.

Ruins of Buildings and Structures

Excavating historical archaeological sites is an expensive and time-consuming activity that may sometimes be avoided. Loss of integrity, a preponderance of informative surface archaeological deposits, the results of prior excavation work, or sufficient historical records and information regarding that type of site may all provide adequate grounds for a finding for or against eligibility without having to excavate. Even if some buried deposits are anticipated, the importance of some historical archaeological sites (particularly those that consist largely of surface deposits) often can be addressed without excavation. For example, a construction camp in Inyo County was determined eligible for inclusion in the National Register under Criterion D based solely on the abundant and relatively intact surface deposits found there. Make the argument for or against eligibility of a historical archaeological site without test excavation in the HRER.

Historical archaeological resources that have clearly lost their integrity and lack historical importance or the ability to address important research topics should be determined as not eligible for inclusion in the National Register. In such a situation, document the lack of integrity in the HRER. For instance, simply stating that an orchard was planted on top of the location of a former adobe is not sufficient. On the other hand, information from the landowner that heavy equipment churned the earth to a depth of five feet to prepare the ground for planting is the type of important detail needed to support the lack-of-integrity statement. This fact would then be considered in relationship to the expectation for archaeological deposits, based upon knowledge of similar site types and potential for effect (i.e., is there an expectation for deposits below five feet and what is the depth of construction impacts).

In some cases, evaluation may be unnecessary if the value of the site appears to be limited to its research potential, and an Extended Phase I (XPI) investigation reveals that the boundaries of the property are outside of the area directly impacted by project construction. See Section 6-6 for a discussion of the justification for an XPI study, as well as Exhibit 5.2.

Where evidence exists that demonstrates the site possesses integrity and archaeological data potential, such as through remote sensing (see Exhibit 5.10) or knowledge of similar site types and degree of disturbance, one may make an argument that a site is eligible based on its potential to yield information. The potential to yield information must be demonstrated in the HRER in a well-developed, rigorous research design that considers the site-specific context with comparisons to similar historical archaeological sites.

The argument for eligibility based on information potential with no test excavations should be used sparingly. Save it for situations where property access problems would delay completion of the environmental document. It might also be used when the project’s effects to the site can be reasonably assessed and there is enough information on integrity to make a final effect determination for the site.

Evaluation of historical archaeological sites without excavation is documented in the HRER. Caltrans PQS at the Co-PI level and consultants who meet the same qualifications may perform the evaluations with peer review by a PI-level historical archaeologist.

In some cases where the provisions of the Section 106 PA do not apply, such as on projects involving tribal lands or state funded projects, it may be appropriate to document in a Letter Report historical archaeological sites that are not eligible for inclusion in the National Register. See Exhibit 6.1 for format of a letter report. Most of these resources will be exempt properties as described in Section 106 PA Attachment 4 and discussed in Chapter 4 and Section 6-4.2, but appropriate historical research and field survey should be conducted to ensure the resource meets the requirements of Section 106 PA Attachment 4.

A finding that a historical archaeological site is not eligible for inclusion in the National Register, at this stage, may be a result of any one of the following factors:

• Demonstrated loss of site integrity.
• Absence of historical associations or important design value.
• Demonstrated lack of archaeological research potential.

While an archaeological survey may be able to record information in the field to document a loss of site integrity, the appropriately qualified historical archaeologist must evaluate the latter two qualities. If it is determined that a historical archaeological site meets at least two of these three factors, include the results of the evaluation and justification for its conclusions in a Letter Report.

Many historical archaeological resources are likely to fall into this category of ineligibility. However, be careful to avoid blanket assumptions as to lack of historical associations or archaeological research potential until adequate information regarding a resource's historic context and associations can be established. For instance, unassociated tailings piles, isolated refuse dumps, mine test pits, and rock walls are all likely to be determined not eligible for inclusion in the National Register. However, some examples of those resource types, such as a rock wall delineating the boundary of a Mexican rancho, may be potentially eligible because of their important historical associations with themes developed in a historic context. They also may be part of a larger historic property (i.e., a contributor to an eligible property). .

Peer review of Letter Report

Approval and Distribution of Letter Report

Where possible, evaluate historical archaeological sites without excavation because of the cost and time commitments associated with all types of test excavation programs. Furthermore, excavations by their very nature destroy sites. Chapter 5 discusses XPI and Phase II studies in detail and Exhibits 5.2, 5.3, 5.4, and 5.5 provide the format and content of these proposals and reports. This section focuses on the differences inherent when dealing with historical archaeological sites.

When the evaluation of a historical archaeological site cannot be completed based on historical research alone, however, test excavations need to be conducted to:

• Establish the boundaries of the resource relative to a project's direct impact area (XPI Studies or XPI).
• Evaluate the research potential of the property (Phase II Studies).

Test excavations usually are conducted when their results are essential to determining the site’s ability to address important research topics. They may be equally important for understanding a project’s effects to the site, specifically for determining locations of intact portions of the site relative to the Direct APE for the proposed project. Testing is not warranted for historical archaeological sites that:

• Lack integrity and/or clearly defined historical associations.
• Lack research potential (e.g., sites with little or no cultural deposits).
• Can be adequately evaluated using historical information and surface inspection.

XPI and Phase II studies follow similar procedures, differing primarily in their scope and objectives. Chapter 5 and Section 6-6.2 discuss the scope and objectives of each type of study. Because archaeological excavations usually require large commitments of time and public expense, both XPI and Phase II testing procedures must be justified in the proposal. See Section 6-7 for a discussion of how to prepare proposals for these studies. Planning and conducting archaeological testing programs at historical archaeological sites follow many of the same procedures already considered in Chapter 5. Unique requirements for work at historical archaeological sites are discussed in separate sections covering pre-field preparation and fieldwork (Section 6-8), field safety (Section 6-8.2), laboratory analysis (Section 6-9), and reporting requirements (Section 6-10). See also Exhibit 5.9 which contains the Excavations pre-field checklist, Exhibit 2.6 regarding safety, and Exhibits 5.3, and 5.5 that contain reporting formats.

When excavation is required, allocate adequate time for testing programs. Assuming the work is a typical XPI study at one site, and adequate project mapping is available at the inception of that work, the average XPI study, including excavation and report completion, takes six months. Based on the same criteria, Phase II investigations normally require 12 months. Special circumstances such as limitations on rights of entry or special restrictions associated with endangered species or seasonality may significantly lengthen these time frames. Exhibit 2.3 contains estimates of the time and effort required to complete such excavations.

The objectives of a test excavation program always need to be stated clearly and justified, with specific thresholds defined to establish when the work can be considered to have met those goals. An XPI study may be expanded into a Phase II testing program in cases where the proposal has been specifically designed to accommodate that eventuality. It is often helpful to prepare a combined XPI/Phase II proposal in cases where time is of the essence and there is a reasonable expectation for that outcome.

XPI Goals

Phase II Goals

When an XPI or Phase II study is justified, the PI historical archaeologist must prepare, or directly supervise the preparation of, an excavation proposal. Likewise, the historical archaeologist is responsible for implementing the work. When XPI or Phase II studies involve sites occupied by Native Americans during the historic era, either a historical archaeologist or an appropriately trained prehistoric archaeologist may prepare the proposal. .

The excavation proposal must include a:

The level of detail required for a given proposal will depend on the:

In general, XPI study proposals should be much simpler than those prepared to justify Phase II studies. Exhibits 5.2 and 5.4 contain supplementary guidance on scope and contents of proposals for XPI and Phase II studies. All proposals should include specific provisions for obtaining necessary entry rights and permits..

Curation Plans

When an XPI study is justified at a historical archaeological site, the proposal follows the same format (Exhibit 5.2) as would be prepared for a prehistoric archaeological site. It states why the XPI study is needed, the field methods to be used, and the basis for determining when the study goals have been met and fieldwork can cease. Since an XPI investigation should be limited in scope, the proposal should be brief. .

XPI Proposals should include the:

• Reasons the study is needed.
• Goals of the investigation.
• Field and laboratory methods to be used.
• Thresholds used to establish when the study has achieved its objectives.
• Availability of appropriately qualified personnel, whenever possible.
• Schedule for completing the work.

The introduction to the proposal should indicate the study's goals and why an XPI, rather than a Phase II, study is appropriate. This document should supply a historic context, site description, and a brief discussion of the resource's potential importance in relation to current research topics.

Define the methods to be used in the scope of work. Flexibility is most important, and a combination of mechanical excavation, surface scrapes, auger holes, shovel test pits, rapid recovery units, and control units may be required. Since minimal recovery of archaeological materials is anticipated, proposing only limited laboratory work is appropriate. Include curation plans in the event that potentially significant deposits are encountered and a follow-up Phase II study is needed. State explicitly whether materials will be curated.

Phase II proposals require more complete development of a research context against which any remains that are encountered will be measured. Because such work is conducted with the expectation that potentially significant deposits and features may be found, develop research questions to cover all expected areas of potential importance. Define the explicit data requirements for each topic.

Excavation efforts should be focused on that portion of the site within the Direct APE; however, particular research objectives may direct excavations to specific areas, components, or features within the site. Other features may not warrant any effort beyond noting their presence.

A PI-level historical archaeologist must prepare, or directly supervise the preparation of, the Phase II proposal, in consultation with historians or architectural historians or other specialists if a project team has been formed. In cases where excavation is planned at a historical archaeological site associated exclusively with historic Native American use, either an appropriately qualified prehistoric or historical archaeologist can prepare the Phase II Proposal (see Exhibit 5.4 for guidance).

The Phase II Proposal should include:

• Need for the Phase II study.
• Goals of the investigation.
• Field and laboratory methods to be used.
• Historical research methods.
• Research Design that explains the data needs to address important research issues.
• Thresholds used to establish when the study has achieved its objectives.
• Availability of appropriately qualified personnel, whenever possible.
• Schedule for completing the work.
• A curation plan.

XPI and Phase II Proposals that describe the excavations to be performed at historical archaeological sites should follow the general format and content guidelines found in Exhibits 5.2 and 5.4. Complete a revised archaeological site record and append it to the report if additional information is recovered beyond that recorded in the ASR. For example, additional information may include redefined limits or changed nature of the archaeological site.

Peer Review of Excavation Proposals

Pre-field preparation includes the activities outlined in the excavation checklist in Exhibit 5.9, such as securing:

• Permits.
• Access rights.
• Underground service alert.
• Detailed project mapping.
• Appropriately qualified crew.
• Equipment.
• Facilities.
• Supplies.
• Transportation.

These requirements largely duplicate those discussed in Chapter 5. However, some additional considerations bear mention here with regard to excavations at historical archaeological sites.

Testing historical archaeological sites requires a great deal of methodological flexibility to yield maximum information. Design the proposals to allow considerable freedom in choice of field methods, especially with regard to excavation unit size and shape. Fieldwork should then follow the approved proposal.

Field methods for testing historical archaeological sites often differ from those used to sample prehistoric archaeological sites. The types of sampling strategies commonly used at prehistoric archaeological sites (particularly random sampling) are not very useful when investigating historical archaeological sites, since sample units may more appropriately be the identified features themselves. It may be necessary to clear vegetation from broad areas of the site, or features within the site, in order to locate features or artifact concentrations before actual excavation.

Some historical archaeological sites require exploratory backhoe trenches or grading to provide information on site stratigraphy and feature location. Trenching may be an essential first step for investigating sites with long occupations where there may be buried components, flood deposits, or other vertically stratified elements. Others (such as single component sites) may require shallow block exposures or broad excavations that have the potential to reveal a maximum number of subsurface and surface features.

Subsurface features may be located by means of trenches, shovel tests, backhoe scrapes, or probes with metal rods in search of changes in soil compaction, color, or constituents. They may also be discerned by using metal detectors, remote sensing, and other geophysical techniques, although such procedures require the use of experienced analysts. The topography of the site may also provide clues to the presence of subsurface features. Once the important features of a site are located, controlled test units may be appropriate to maximize the information yield with a minimum amount of disturbance.

Mapping

Principal Investigator On Site

Health and safety issues that should be considered carefully prior to every project are discussed in Chapter 4, Section 4-6.3. Chapter 2 in the Caltrans Survey Manual describes standard field safety precautions such as traffic management, first aid, and other routine practices as outlined in Exhibit 2.6.

A tailgate safety meeting tailored to the specific needs of each excavation project must be conducted at the inception of and at intervals during every field excavation project.

Special Hazards

Health and Safety Plan

Laboratory work normally entails:

• Washing or preparing samples (if necessary).
• Cataloging.
• Identifying materials, artifact types, and date ranges attributable to those items.
• Quantifying artifacts (total pieces and minimum number of individual items).
• Where appropriate, suitably packaging and conserving materials that will be retained for permanent curation.