I. INTRODUCTION

This document constitutes the fourth in a series of coral monitoring reports required by the U.S. Corps of Engineers (USCOE) permit which was issued to IOTA Partners for the archeological excavation of the SANTA MARGARITA, a Spanish galleon which sank on Rota's fringing reef in 1601.

Special Condition 3 established a monitoring plan to examine the health of adjacent corals throughout the duration of the project. As previously discussed in the three 1999 season reports, four coral reference sites were identified and marked with rebar: two sites were positioned up-current from the "project site area" (ie., sand pit) while two sites were situated down-current. These sites were further delineated into shallow and deep water. Although, these four reference sites were still marked from the 1999 season, new rebar markers were installed to make them more visible to divers. Coral colonies at each reference site are photo-documented for use by the regulatory agencies in determining their general health. The purpose of this condition was to be able to identify early on, impacts to reference corals and thus provide the opportunity for specific data collection to determine whether the impacts were originating from project related activities. If further research correlates coral impacts to project activities, then additional mitigative measures would be developed and implemented.

This report will focus more on coral related issues (transplantation, monitoring, general health) associated with USCOE permit conditions while the water quality aspect of this permit condition will be fully addressed by the Section 401 WQC issued by the DEQ on 5 February 1999. In keeping with the sampling scheme previously developed by the DEQ, an ambient water sample is obtained at the excavation area (reference site) prior to excavation, while the compliance water sample is obtained four hours after excavation commences, approximately 100 feet downstream from the excavation area. If excavation activities exceed an 8-hour period on any given day, then a second water sample is obtained from the compliance site. The resulting turbidity measurements from the days water samples are then FAXed to the DEQ that evening. Water samples and turbidity readings are obtained on any day excavation occurs. The turbidorneter and field personnel who obtain the water samples have all been previously approved by the DEQ. Compliance with the Section 401 WQC is assumed to cover the turbidity related requirements identified in the USCOE permit conditions.

II. PRE-EXCAVATION WATER QUALITY DATA

Due to the rough surf conditions caused by super typhoon Damrey, we were not able to obtain much preexcavation water quality data,, One dive was foolishly made by myself on May 10" prior to actual in-water work and the turbidity at the project site was so high that water visibility extended a maximum of maybe 10 feet. A later dive on May 17th found many of the corals surrounding the lower rim of the sand pit covered in fine silt. Several corals were noticeably excreting slime which is a natural reaction of certain coral species to rid itself of excess sediment. One bleached coral was identified, but how or why it died is unknown.

Turbidity data that was collected is presented below.

III. ASSESSMENT OF REFERENCE CORALS

Photographs of live corals from the four reference sites were taken on 18 May 2000 and are shown in Figures 1, 2, 3 and 4. The following qualitative assessment is based on general visual observations.

A. UP-CURRENT SHALLOW:
Photographs of the corals at this reference site are shown in Figure 1. This is the first assessment prior to commencement of this years work season; there appeared to be no substantial changes in coral health from the October 1999 assessment.

B. DOWN-CURRENT SHALLOW:
Photographs of the corals at this reference site are shown in Figure 2. This is the first assessment prior to commencement of this years work season; there appeared to be no substantial changes in coral health from the October 1999 assessment.

C. UP-CURRENT DEEP:
Photographs of the corals at this reference site are shown in Figure 3 3. This is the first assessment prior to commencement of this years work season; there appeared to be no substantial changes in coral health from the, October 1999 assessment.

D. DOWN-CURRENT DEEP:
Photographs of the corals at this reference site are shown in Figure 4. This is the first assessment prior to commencement of this years work season; there appeared to be no substantial changes in coral health from the October 1999 assessment.

IV. MITIGATION MEASURES IMPLEMENTED

SEDIMENT PLUME CONTROL:

Based on practical experience gained during the 1999 season with developing and utilizing several turbidity controlling devices, IOTA Partners arrived this season with what they believe to be an improvement on last years design.

Turbidity will be controlled by erecting a 40' by 60' tarpaulin "tent" slightly off the bare sandy substrate and centrally situated within the sand pit area. The sediment tent will be semi-enclosed on three sides with one end open to receive the sediment plume (Photograph 3 below). The three sides will not extend all the way to the bottom but will be slightly elevated off the sandy substrate as previous experience has shown that it will quickly get buried. The terminus of the discharge pipes are oriented toward the tent entrance (Photograph 4 below) along the longest axis so that the sediment plume has a longer period of time to settle. During the testing period for the eductors, the discharge pipes were positioned in several different locations in order to maximize the tents effectiveness. Photographs 3 and 4 below show the terminus of the discharge pipes approximately 15 feet from the entrance of the sediment tent. Further modifications to the existing system may be in order depending upon its efficiency over time and the type of sediment being discharged. Sediment type has been found to be important in determining the effectiveness of any type of sediment controlling device.

MOORING RELATED ISSUES:

Anchoring points for the work barges were determined by the strength of the holdfast and whether the immediate area contained very much coral growth. The anchoring chain was wrapped in fire hose, snaked through the limestone substrate and shackle together (Photograph 1 below). A mooring line was then attached to the anchor chain and secured to the work barges. Each work barge has four mooring points, which will allow some maneuvering ability over the site by shortening or lengthening the mooring lines. Depending upon the circumstances, buoys were installed on mooring lines (Photograph 2 below) to keep the lines off the substrate which both protects the corals as well as keep the mooring lines from being chaffed.

V. CORAL TRANSPLANTATION

At least initially, the area that was identified for excavation during the 1999 season will be targeted this season. Excavation will, of course, be determined upon the artifact trail and the direction from the on-site archaeologist. At this time, the area targeted for excavation has been previously cleared of branching corals as required under USCOE permit # 960100004 (as amended 23 November 1998). However, one large branching coral situaed on the peripheral of the targeted excavation area was transplanted on 18 May as it appeared to be in an area where it could be damaged.