ESBD_463281_1761072169674_Addendum No.1.pdf

Date: October 21, 2025

ADDENDUM #1

To the proposal documents for RFP# 808-26-243671, Geophysical Survey Specialist Services for Texas Historical Commission

RFP Submittal Deadline: November 21, 2025, 2:00 PM CT

This addendum forms a part of the Contract Documents and modifies the RFP Documents issued October 20, 2025, as noted below:

The Respondent's attention is directed to the fact that addendum item and specifications as noted herein are not necessarily referenced to all occurrences in the documents.

Respondent shall acknowledge receipt of this addendum where indicated; failure to do so may subject the Respondent to disqualification.

This addendum consists of Five (5) pages, including this page.

This Addendum updates sections 2.1 (Service Requirements) to 2.3 (Reporting and Deliverables), including Exhibit E, Price Schedule. Respondents are required to complete the revised Exhibit E, Price Schedule which outlines the cost breakdown for Phase I and Phase II, and submit it with their RFP bid packet. This addendum also updates the correct RFP# from 808-25-243671 to RFP# 808-26-243671 throughout the RFP.

Revise Sections:

SECTION II

STATEMENT OF WORK

2.1 SERVICE REQUIREMENTS. Services shall include the requirements contained in this RFP.

Services set forth that contain the words "must" or "shall" are mandatory and must be provided as specified with no alteration, modification, or exception. Services set forth that contain the words

"may" or "can" allow Respondents to offer alternatives to the manner in which the commodities/services are provided. The requested services and corresponding deliverables are detailed in the subsections below.

2.2 PROJECT OBJECTIVES. The primary objective of the overall project is to discover the shipwrecks and settlement(s) associated with Aury’s tenure at Matagorda, however, other unrelated archeological sites may be discovered during the course of fieldwork. Pass Cavallo is the historical commercial entrance to Matagorda Bay, prior to the creation of the Matagorda Ship Channel through

Matagorda Peninsula in 1966. The historical inlet has not been subject to large-scale modification and has a high potential to contain undiscovered underwater archeological sites. According to THC data, nearly a hundred reported, unverified shipwrecks are in the vicinity of the project area. Work performed towards the project objectives will occur as two tasks: (1) conduct of the survey and (2) post-fieldwork data processing, analysis, and report preparation.

The traditional remote-sensing survey onboard Anomaly II is planned for 27 days and will employ a

Geometrics G-882 marine magnetometer and EdgeTech 4125 dual frequency side-scan sonar for data acquisition. The purpose of the investigation is to detect remote-sensing targets representative of submerged cultural resources. The survey will be conducted in accordance with agency requirements presented in the Texas Administrative Code, Title 13, Part 2, Rule §28.6. The survey will be at 20-m survey intervals with significant remote-sensing targets under consideration also being subject to close-order refinement survey. As part of the fieldwork, specific previously detected shipwrecks and significant remote-sensing targets from earlier archeological studies that are in the vicinity of the project area will be re-examined. All magnetic data will be processed and presented as contour isolines in accordance with state survey standards (13 TAC §28.9). The data will be evaluated using standard underwater archeology interpretative models, including the North-

Alignment Model. Magnetic targets verified as shipwreck archeological sites will be included in the proprietary database developed in conjunction with the north alignment model. Nine days is allocated for post-fieldwork data processing, analysis, and assistance in preparation of illustrations and summary content for the required technical report.

The remote-sensing specialist will assist in mobilization and deployment of the survey vessel and equipment. The Respondent’s duties will include assisting in supervision of field data acquisition and post fieldwork data processing with a specific focus on magnetic data. As a project objective is to incorporate verified shipwreck archeological sites into the North-Alignment Model database, the

Respondent must have access to this propriety study and product. The Respondent must meet the minimum professional qualifications for an underwater archeologist presented in 13 TAC

§26.4. The Respondent should have previous experience conducting underwater archeological investigations at Pass Cavallo.

2.3 REPORTING AND DELIVERABLES.

The Respondent will assist in fieldwork activities and report preparation. Responsibilities include field data acquisition, processing and interpretation of remote-sensing data, and assistance in preparation of data figures and summary information for the required technical report.

Services are expected to take place between the period covering December 10, 2025, through August

31, 2027. An initial meeting or conference call to agree on the work schedule and approach must be scheduled to occur within (2) two weeks of the last signature date of the contract. Services shall be performed under the coordination of THC’s Archeology Division.

Benchmarks shall be established based on the Respondent’s project information provided in their proposal, which must include a timeline/schedule of work that outlines how and when Respondent proposes to complete the project.

It is the awarded Respondent’s sole responsibility to ensure that all status reports are delivered to the proper recipient(s) at the proper time. Documents will be considered delivered only when received by THC’s designated Project Manager. Services are deemed completed when THC has reviewed the reports, all requested revisions have been addressed, and THC has given final, written approval of all services required by the contract.

EXHIBIT E

PRICE SCHEDULE

Having carefully examined the Requests for Proposal for Geophysical Survey Specialist Services for the

Texas Historical Commission and all other contract documents, this undersigned proposes to the required services for a sum of:

Basic Proposal Items Lump Sum Price

Task 1 - Geophysical Survey Specialist Services (27 days of survey including mileage/meals/lodging)

Task 2 - Data processing, analysis, and assistance in preparation of the technical report (9 days).

LUMP SUM PRICE $

Additional premium options offered may be detailed below.

(Provide descriptions)

Lump Sum Price

Vendor Name: ___________________________________________________

Address: __________________________________________________

Email Address: __________________________________________________

Print Name: ____________________________________________________

Signature: ______________________________________________________

Title: __________________________________________________________

(Exhibit E, Price Schedule is for the convenience of the contractor to accurately estimate costs. The total amount of the contract will not exceed the total price schedule. It is the responsibility of the Applicant (Contractor) to pay for all expenses incurred during the performance of the contract. These expenses will be reimbursed by using funds from the total amount of the contract according to the payment schedule of the contract.)

NOTE: THIS FORM MUST BE COMPLETED & RETURNED WITH THE SUBMITTAL

END OF ADDENDUM

Bidder acknowledges receipt of the following addenda: Addendum #1__________(initial)

WARNING: BIDDER’S FAILURE TO ACKNOWLEDGE RECEIPT OF ADDENDA MAY RESULT

IN REJECTION OF THE PROPOSAL.