Ox Bel Ha Water Protection Project

Home , Sistema Dos Ojos, Sistema Ox Bel Ha

Sian Ka’an Exploration Expedition November, 2005 – June, 2006

Final Report for The Nature Conservancy

Centro Investigador del Sistema Aquífero de Quintana Roo, A.C. Retorno Copan, Lote 85, Manzana 22, Playacar Fase 2 Playa del Carmen, Quintana Roo, 77710, MÉXICO Tel/Fax +52 (984) 873-1239 [email protected]

Sam Meacham, Project Coordinator

This report compiled with the assistance of Fred Devos, Christophe le Maillot and Daniel Riordan

September, 2006

This project and report are dedicated to the memory of

The Honorable Ann W. Richards Friend and patron of CINDAQ

2 Table of Contents

OX BEL HA WATER PROTECTION PROJECT ...... 1

ACKNOWLEDGEMENTS ...... 6

FIELD TEAM FOR THIS PROJECT:...... 7

EXECUTIVE SUMMARY ...... 8

OBJECTIVES: ...... 8 PRINCIPLE ACTIONS REALIZED ...... 9

AREA OVERVIEW ...... 11

INTRODUCTION...... 11 FORMATION OF THE AQUIFER ...... 11 THE THREAT OF DEVELOPMENT...... 12 THE IMPORTANCE OF EXPLORATION, OBSERVATION AND MAPPING...... 15

OX BEL HA WATER PROTECTION PROJECT 2005-2006 ...... 18

AREA OF STUDY (THE NORTHERN BOUNDARY AREA OF THE SIAN KA’AN BIOSPHERE RESERVE)...... 18 CINDAQ AND MCEP ...... 19 PREPARATION AND LOGISTICS ...... 20 DIVING PROCEDURES...... 21 CAVE SURVEY AND CARTOGRAPHIC METHODS...... 22 SURFACE MAPPING ...... 23 RESULTS OF THIS PROJECT ...... 24 FUTURE WORK IN THIS AREA...... 25 NOVEMBER 2005...... 27 SURFACE EXPLORATION NOVEMBER 27TH, 2005 ...... 28 FEBRUARY 2006...... 32 SURFACE EXPLORATION FEBRUARY 7TH-8TH, 2006 ...... 33 DIVING OPERATIONS FEBRUARY 7TH, 2006...... 37 DIVING OPERATIONS FEBRUARY 8TH, 2006...... 43 DIVING OPERATIONS FEBRUARY 9TH, 2006...... 49 DIVING OPERATIONS FEBRUARY 10TH, 2006...... 58 MARCH 2006 ...... 64 DIVING OPERATIONS MARCH 23RD, 2006 ...... 65 DIVING OPERATIONS MARCH 24TH, 2006 ...... 72 DIVING OPERATIONS MARCH 25TH, 2006 ...... 80 APRIL 2006...... 90 SURFACE EXPLORATION APRIL 6TH-7TH , 2006 ...... 91 DIVING OPERATIONS APRIL 5TH, 2006...... 95 DIVING OPERATIONS APRIL 6TH , 2006...... 102

3 DIVING OPERATIONS APRIL 7TH, 2006...... 111 DIVING OPERATIONS APRIL 8TH, 2006...... 116 MAY 2006 ...... 121 SURFACE EXPLORATION MAY 9TH, 2006 ...... 122 SURFACE EXPLORATION MAY 17TH-18TH, 2006 ...... 126 DIVING OPERATIONS MAY 16TH, 2006...... 130 DIVING OPERATIONS MAY 17TH, 2006...... 132 DIVING OPERATIONS MAY 18TH, 2006...... 137 DIVING OPERATIONS MAY 19TH, 2006...... 144 DIVING OPERATIONS MAY 20TH, 2006...... 150 JUNE 2006...... 155 DIVING OPERATIONS JUNE 13TH, 2006...... 156 DIVING OPERATIONS JUNE 14TH, 2006...... 158 DIVING OPERATIONS JUNE 15TH, 2006...... 163 DIVING OPERATIONS JUNE 16TH, 2006...... 168

THE SIAN KA’AN BIOSPHERE RESERVE...... 173

OVERVIEW OF SIAN KA’AN BIOSPHERE RESERVE ...... 174 HABITATS FOUND IN THE SIAN KA’AN BIOSPHERE RESERVE...... 175

SCIENTIFIC REPORTS ...... 178

DETECTING SUBSURFACE CONDUITS WITH ELECTROMAGNETICS ...... 179 BACKGROUND FOR THE PROJECT...... 179 ELECTROMAGNETIC GEOPHYSICAL SURVEYS ...... 180 THE VIGIA CHICO ROAD MEASUREMENT ...... 182 THE HOLBOX FRACTURE MEASUREMENT...... 183 THE CAAPECHEN MEASUREMENT ...... 185 FUTURE PLANS FOR RESEARCH IN THE AREA ...... 188

4 Acknowledgements

CINDAQ A.C. wishes to express its gratitude to the following communities, individuals and institutions, without whose support this project would not have been realized.

The Ejido Jose Maria Pino Suarez The Ejido Tulum Ms. Diana Bermudez and Ms. Marie Claire Paiz of The Nature Conservancy Biol. Gonzalo Merediz, Albino Tun and the entire staff of Amigos de Sian Ka’an Biol. Alfredo Arellano CONANP Biol. Francisco Ursua and Omar Ortiz of the Sian Ka’an Biosphere Reserve

The Mexican Cave Exploration Project Mr. Christian Thomas and the Fédération Française de Spéléologie

Mr. Carlos Marin, Mr. Gavin Greenwood and the staff of Alltournative SA de CV PIXEL Press SA de CV The Honorable Ann W. Richards Mr. and Mrs. Alfredo Medina

Technical University of Denmark El Centro para el Estudio del Agua Dr. Mario Rebolledo Dr. Luis Marin Mr. Mario Gongorra Lopez of INEGI Cancun CEMDA

Aqua Exploration El Centro de Visitantes de Sian Ka’an Cooperativa U Yo Ochel Maya Global Underwater Explorers Ecocolors SA de CV Raga Tours Zero Gravity Dive Center

Jim Coke The Explorers Club of New York Lic. Fernando Doblado Rueda and Lic. Antonella Vasquez Mr. Kenneth Johnson and Ms. Miriam Vega Mr. Daniel Tun Oy, Mr. Jose Tun Oy, Mr. Marcos Cahum Tun Mr Candido Caamal, Mr. Ismael Caamal Mr. Remualdo Ancona , Mr Aldo Ancona Rejon, Mr. Julian Loria Perez, Mr. Estevan Ek

Field Team for this project:

Dive Team

Franco Attolini Alejandro Alvarez Roberto Chavez Arce Fred Devos Jarrod Jablonski Christophe Le Maillot Luca Magheli Andrea Marassich Daniel Riordan Gianmario Rocca Per Thomsen Mario Valotta

Surface Exploration

Roberto Chavez Arce Christophe Le Maillot Sam Meacham Dr. Mario Rebolledo Simon Richards Jose ‘El Tio’ Sanchez Robert Schmittner Jack Sherman

Science Team

Mahlene Louise Rehback Bibi Ruth Neuman Andrea Tampieri Dra. Guadalupe Velazquez Oliman Dra. Rosa Maria Leal Bautista

7 Executive Summary Rampant development continues to threaten one of Mexico’s largest, most pristine and culturally significant aquifers. The coast of Mexico’s Riviera Maya is facing unprecedented growth that ranks it among the fastest growing regions of the world. Out of sight and mind, the flooded cave systems of the region play a crucial role as the conduits for freshwater moving from the jungle interior out to the Mesoamerican Barrier Reef. The need to explore and better understand the aquifer of Northern Quintana Roo is at a critical juncture as it directly influences the health and economic well being of the human population above it and the many ecosystems it nourishes from below. Due to the aquifers extreme fragility and vulnerability to contamination the rampant development at the surface is nearing a tipping point. Since this region contributes approximately 10% of Mexico’s GNP, the impact of a contaminated aquifer and associated ecosystems would have far reaching and potentially disastrous results not only for the regions tourist based economy but for Mexico as a whole. Cave diving explorers provide a critical knowledge base by mapping the subterranean waterways, providing a foundation for scientific work that ultimately can help understand and protect the aquifer and the many ecosystems that it supports. No cave system represents the area better than Sistema Ox Bel Ha. With over 146 kilometers of surveyed passageway, it winds its way 8.5 kilometers from the jungle interior to the edge of the Mesoamerican Barrier Reef, passing below, through, and into, every major ecosystem found in the region. Within Ox Bel Ha and in outlying caves, significant archeological discoveries have been made that are helping archeologists understand the peopling of the Western Hemisphere. Major arteries of the system pass close to the Sian Ka’an Biosphere Reserve (SKBR) giving rise to the belief that there may be a hydrological connection between Ox Bel Ha and SKBR. The threat of development looms large over the Ox Bel Ha area. In early 2006 the Municipality of Solidaridad began to discuss in earnest the urban development plan for the Tulum area. Parts of this plan are placed directly above the Ox Bel Ha system. If a link to Sian Ka’an exists, then inappropriate development in Tulum risks contaminating three of the world’s great treasures: the underground aquifer of Ox Bel Ha, the surface wetlands of the Sian Ka’an Biosphere, and the Mesoamerican Barrier Reef. Central to the objectives of this exploration project are the confirmation of such a link, and the protection of this wilderness area, and the vital resource coursing through its veins below.

Objectives: • To search for and assess possible cenote entrances in the area between Ox Bel Ha and SKBR utilizing state of the art GPS technology. • To confirm and record points along the northern boundary line of Sian Ka’an • To locate and assess cenote entrances within Laguna Caapechen and Laguna Boca Paila for exploration potential • Cartography and photo/video documentation of both surface and underwater areas explored on this project • To promote and facilitate scientific research in the areas explored on this project • To highlight the relationship between the Ox Bel Ha cave system the SKBR and the Mesoamerican Barrier Reef through continued public presentations

Principle actions realized With these objectives in mind, and financial support received from The Nature Conservancy (TNC), Alltournative SA de CV and private contributions, and the cooperation of the Comision Nacional de Areas Naturales Protegidas (CONANP), Amigos de Sian Ka’an, the Mexican Cave Exploration Project, Centro para el Estudio del Agua and the Technical University of Denmark, CINDAQ A.C. was able to coordinate the efforts of divers and scientists to reveal what may prove to be the largest of the underground rivers yet found in our region. Although a direct physical connection to Ox Bel Ha has yet to be found it can still not be ruled out. There is growing evidence that the underground rivers of the SKBR are far more extensive than we could ever have imagined and in need of further investigation. As a result of this project the following actions were realized:

• 6 underwater cave entrances in Laguna’s Caapechen and Boca Paila were located and assessed • 5 of the entrances were entered by cave diving explorers • 37 dives were performed in these 5 entrances • More than 7,000 meters of cave passageway was explored and mapped • Dive teams used standardized data collection slates to record detailed information of the caves • Video and photographic documentation of the largest of the caves Entrada Caapechen was accomplished • An abundance of bacterial growth was observed within Entrada Caapechen • Major flow of water within the caves and large cave passageways suggests that there is a massive cave system draining the area from Laguna Chunyaxche towards the coast and Lagunas Caapechen and Boca Paila • 7 cenotes seen on aerial and satellite imagery were located and assessed for diving potential, one of these cenotes has high potential for exploration and is well placed upstream of Entrada Caapechen • Major points along the northern boundary line of the Sian Ka’an Biosphere reserve were confirmed and recorded using GPS • Surface conductivity tests were done by the Technical University of Denmark • Water chemistry parameters were measured in Entrada Caapechen by the use of an underwater data sonde and water sample collections. This was done in conjunction with the Centro para el Estudio del Agua in Cancun • Healthy populations of underwater and surface biology were observed and recorded, including manatees, a pair of pumas and the first recording to our knowledge of ctenophores (jellyfish) in a cave • CINDAQ was included in round table discussions by the Municipality of Solidaridad to discuss the future urban development plan of Tulum. A convincing case was made to the planning commission as to the importance and fragility of the cave systems surrounding Tulum • Thanks to CEMDA, an aerial overflight was performed to assess from the air a group of cenotes in the Zona Nucleo of Sian Ka’an

9 It is the genuine hope that our exploration teams efforts will help foster greater scientific study and further exploration, the end result being the protection of this magnificent area. We all feel that it has been a true privilege to work within the SKBR.

Area Overview Introduction Freshwater: the one resource that human beings depend on more than anything, and the one that most of us take for granted. As we enter the 21st century, world attention is turning to dwindling freshwater reserves and the need to conserve them for future generations. To find a large pristine freshwater supply in this world is rare. Mexico’s Yucatán peninsula contains such a resource.

Figure 1

Made up of the states of Campeche, Yucatán, and Quintana Roo (figure 1), the peninsula is a land rich in both human and natural history. Dominating the landscape are temples and pyramids that testify to the achievements of the ancient Maya civilization. Today, the Maya culture still thrives on the peninsula with many traditions and a strong cultural identity intact. Beneath the ground runs a common thread that has directed the distribution of life on the peninsula for thousands of years; the world of the cenotes and underground rivers. These underwater labyrinths are part of an intriguing puzzle that explorers and scientists are beginning to piece together. However, along Quintana Roo's Caribbean coast, breakneck development from Cancun to Tulum threatens these freshwater reserves and all of the ecosystems that rely on them including the Mesoamerican Barrier Reef and The Sian Ka’an Biosphere Reserve, a UNESCO World Heritage Site.

Formation of the aquifer A combination of geologic events and climatic change has led to the development of these unique ecosystems. Limestone comprises much of the bedrock of the peninsula. Over countless thousands of years, rainwater, mixing with carbon dioxide formed a weak solution called carbonic acid that dissolved the limestone, forming rivulets that carved out the cave systems. During the last Ice Age, water levels of the world's oceans were approximately 100 meters lower than their present day levels. The caves of the Yucatán peninsula were dry during that period. When the Ice Age came to a close 18,000 years ago, the climate of the planet warmed up, the glaciers receded, and the caves flooded as sea levels rose. What is certain is that these flooded cave systems play an important role as conduits for freshwater traveling from the jungle interior to the Caribbean Sea, making them the

11 critical link between every major ecosystem in the region. Along the way they are used as the primary source of potable water for the population, and, unfortunately, as a convenient place to dispose of waste.

The Threat of Development Rapid development of the coast of Quintana Roo has set the stage for the underground rivers and the aquifer they serve to be detrimentally affected. In the last ten years, the 120-kilometer strip of beach known as the Riviera Maya has seen an explosion in growth. It is considered by many to be the fastest growing area in Latin America with an annual growth rate estimated to be between 20-25%. Behind this boom is the tourist industry, which, while creating jobs, has ironically placed great stresses on the environment that brings millions of tourist back to the area year after year. It took only seven years for the Riviera Maya to equal the number of hotel rooms that took nearby Cancun 25 years to build. Filling these 22,000 rooms are an estimated 2.5 million tourists who visit the Riviera Maya each year. Moreover, many of the region’s major attractions are located along the Riviera Maya, meaning that the millions of visitors to Cancun and cruise ship passengers landing in Cozumel are leaving their footprints as well.

Figures 2 and 3

Much of the area’s development has been based on the premise that it is ‘easier to ask for forgiveness than permission’ (figures 2 and 3). This philosophy coupled with inadequate waste disposal laws and their spotty enforcement has set the stage for a potential environmental and economic catastrophe. Urban sprawl has followed behind. In the most dramatic example, Playa del Carmen, which had a population of 10,000 in the early 1990’s, is now estimated to have a population surpassing 150,000 (Figure 4). Basic sanitary infrastructure has not been able to keep up with this rapid growth.

The two main threats for contamination of the freshwater aquifer are sewage and solid waste. The majority of the local population lives without the benefit of proper sewage

Figure 4 treatment systems or storm sewers. Inadequately built septic tanks leach raw sewage directly into the freshwater aquifer. In some cases it is dumped directly into cenotes, the entrances to the flooded cave systems.

By law, all major hotels are required to have waste treatment facilities. Treated wastewater is injected into the bedrock at a depth that averages between 50 and 100 meters. There are several flaws in this system. As illustrated in Figure 5, cave explorers, working with hydrologists have identified two levels of cave in the area. One is a shallow system that occurs between the surface and 20 meters. It is within this system that freshwater is transported out to the sea. In addition, a deeper system has been identified extending down to 120 meters. At this deeper level and at a distance of 5 kilometers from the coast, hydrologists have measured flow of salt water moving inland. At both levels the cave systems are immense with larger passageways exceeding five meters from ceiling to floor and widths of 20-30 meters or more.

Due to the fact that the treated sewage is mixed with less dense freshwater and then injected into denser saltwater, it will, if allowed, seek the path of least resistance back to the surface, taking it directly into the freshwater aquifer and out to the sea. ‘Deep’ sewage injection is the most efficient way to not only contaminate the freshwater aquifer, but every ecosystem that these cave systems connect. Already, divers have witnessed the contamination of one cave system where high levels of fecal coliform were present.

This drawing illustrates the potential that ‘deep’ injection of sewage has tocontaminate both of these levels and the many ecosystems that the caves connect Figure 5

The other clear threat to the freshwater aquifer of the area is solid waste (Figure 6). It was estimated in 2003 that the Municipality of Solidaridad generated approximately 200 tons of garbage a day. This garbage is transported and deposited into unlined landfills where it is burned. What is left leaches a potent cocktail of contaminants through the porous limestone bedrock, directly into the freshwater aquifer.

This map illustrates the relationship between the Tulum garbage dump, the Municipal water supply pumps (in green), cave systems (in red) and observed water flow. One need not be a hydrologist to understand the potential for contamination presented here. (Quintana Roo Speleological Survey) Figure 6

To see the consequences of contamination, one only needs to look to Mérida located in the neighboring state of Yucatán. Hydrologic studies leave no doubt that the first 20 meters of its 60 meter thick freshwater lens are unfit for human consumption due to widespread contamination.

The Importance of Exploration, Observation and Mapping Over the last twenty years, dedicated cave diving explorers have discovered, explored and mapped 161 underwater caves and cave systems and 450 cenotes and coastal lagoons in the area of the Riviera Maya. As of September, 2006, over 638.8 kilometers of submerged passageway has been surveyed and mapped (Quintana Roo Speleological Survey Website). The four longest underwater cave systems in the world: Sistema Ox Bel Ha, Sistema Sacactun, Sistema Nohoch Nah Chich, and Sistema Dos Ojos, all exist within 25 kilometers of each other. Two of them, Ox Bel Ha, and Nohoch Nah Chich, flow directly into the Caribbean Sea. So far, within the cave systems, 38 ‘stigobitic’ life forms have been identified. These ‘living fossils’ are providing scientists with information on chemosynthesis and the way in which life was distributed on earth. Anthropologists and archeologists, working with cave explorers, have identified important remains that are shedding light on early human settlement in the western hemisphere, not to mention the ritual and everyday use of cenotes by the ancient Maya. Plant life found within the moisture rich ‘microclimates’ of cenotes is allowing botanists to study ancient Maya plant use and cultivation techniques. Ornithologists are interested in studying what role cenotes play as stop over and wintering sites for the estimated 2 billion birds that migrate through the area every spring and fall.

The Ox Bel Ha cave system (in red) as of June, 2006 in relation to the Sian Ka'an Biosphere Reserves northern boundary (in orange) Figure 7

By combining survey data and observations made both inside and out of the caves, cave explorers are allowing a broad picture of the areas aquifer and the ecosystems they connect to emerge. In addition to showing where the flow of freshwater comes from and goes to, the data and maps that cave explorers produce form the foundation for scientific study, and easily allow the identification of potential threats to the freshwater resource of the area. No cave serves as a better example than the Ox Bel Ha System (Figure 7).

Located to the south of the Tulum Archeological Site, Ox Bel Ha is an immense cave system, still in the process of being explored. Ox Bel Ha has over 144.761 kilometers of surveyed passageway, 99 interconnected cenotes including 3 freshwater exits into the Caribbean Sea. In addition, Maya archeological sites have been found both above and below the water, and there are prehistoric archeological sites within the cave that date back to when the caves were dry.

As it winds its way beneath the surface, Ox Bel Ha passes through every major ecological zone in the area, emptying out onto the Mesoamerican Barrier Reef in front of Tulum. Each cenote within the system is an oasis of life, containing a variety of freshwater fish species, reptiles, amphibians, plant life, insects, mammals and birds. Until 1998, Ox Bel Ha lay dormant below the surface and would have remained so if it were not for a dedicated group of cave diving explorers seeking to find out what lay below. Without exploration efforts, an otherwise unknown natural wonder would have gone unnoticed. The impact of Ox Bel Ha on the surrounding area is not completely understood, however it is easy to see potential areas of concern.

It is possible for a diver to enter a cenote at the furthest reaches west of the system and traverse the cave, following the flow of freshwater exiting onto the Mesoamerican Barrier Reef in front of Tulum. In total, it would be a traverse of over 8.5 kilometers. Although this has yet to be done, it is important to realize that if a human being can make this journey, so too can any contaminant. Moreover, unexplored passageway in the area indicates major flow of freshwater in the area of the Sian Ka’an Biosphere Reserve.

The Tulum Development Plan superimposed on the Ox Bel Ha cave system Figure 8

16 One only needs to see the current development plans for the area (Figure 8) around Tulum to see a very disheartening picture emerge as the plan goes right on top of Ox Bel Ha.

Any urban development allowed to proceed in this area will have a direct and certain negative effect on the freshwater resources and every single ecosystem that Ox Bel Ha passes under including the wetlands of an internationally protected biosphere reserve and the Mesoamerican Barrier Reef. Without the maps that cave divers make, there would be no knowledge of what lies below the surface.

Ox Bel Ha is just one example of many cave systems in the area that are threatened. What has been explored so far along the Riviera Maya is only a fraction of what exists.

The objectives of this project were based squarely on growing concern about the threats of contamination to the Ox Bel Ha cave system, the Sian Ka’an Biosphere and the Mesoamerican Barrier Reef.

If we can unlock the riddle of Ox Bel Ha and similar caves by understanding their complex hydrology and relationship with the surrounding environment, we can contribute immeasurably to this regions conservation model and apply it to other areas along the coastline.

17 Ox Bel Ha Water Protection Project 2005-2006

Area of study (The Northern Boundary Area of the Sian Ka’an Biosphere Reserve) The Northern Boundary Area is characterized by almost every habitat found in the Sian Ka’an Biosphere Reserve. The dominant feature is Laguna Chunyaxche to the west, one of the largest freshwater bodies in the state of Quintana Roo. A series of canals, both man-made and natural, connect Laguna Chunyaxche to the coast. (Figure 11)

The northern limit of Laguna Caapechen looking east to the Caribbean Sea (photo Sam Meacham) Figure 10

Two brackish coastal lagoons, Laguna Caapechen to the north and Laguna Boca Paila to the south are connected by a canal way and buffered from the Caribbean Sea by a thin coastal dune that extends south to the settlement of Punta Allen. The lakes are generally shallow with depths from just a few centimeters to an average of two to three meters. Fringing coral reefs of the Mesoamerican Barrier Reef run parallel to the coastline. Hundreds of hummocks dot the landscape creating islands of dense vegetation in the middle of the otherwise flat topography of the savannas and mangroves. The northern boundary area is shared with the Ejido Jose Maria Pino Suarez a collectively governed property of approximately 10,400 hectares. The archeological site of Muyil, while located approximately 16 kilometers inland is considered a port city due to the ability of ancient Maya coastal navigators to reach it by the canal ways connecting Laguna Chunyaxche to the coastline. Two small Maya temples can also be found in the area. The Temple of Xlapak is located at the eastern extremity of Laguna Chunyaxche and at the western terminus of the canal way coming from Laguna Boca Paila. Another smaller temple can be found in Laguna Caapechen. Curiously, the doorway of this small temple is aligned almost perfectly with the principal cave entrance for this project, Entrada

18 Caapechen. In total, six separate cave entrances were located and five of them were explored during this project. All five entrances are located within the brackish lakes of Laguna Caapechen and Laguna Boca Paila. (Figure 12)

Map of the Northern Boundary Area indicating the major lakes. Laguna Muyil is not included Figure 11

CINDAQ and MCEP The two main organizations participating in this project are El Centro Investigador del Sistema Acuifero de Quintana Roo AC (CINDAQ AC) and The Mexican Cave Exploration Project (MCEP). While CINDAQ coordinated the funding, overall logistics, permissions and surface exploration for this project, MCEP focused on all diving related operations and documentation. Working together has allowed us to gather and process a considerable amount of information that we present in this report. Both CINDAQ AC and MCEP share the common vision for the conservation of the regions cave systems through exploration, scientific study and education.

Map indicating the cave entrances located for this project Figure 12

Preparation and logistics Cave diving is an extremely equipment intensive endeavor that requires a very focused frame of mind for both the preparation and execution of dives. Normally, the preparation and execution of our projects are very time and energy consuming. In the case of diving in Sian Ka’an we are very fortunate that the logistics are relatively simple. For all of the previous projects that we have undertaken we have moved an average of 2 tons of equipment by manpower, horses and in one case by helicopter, back into the jungle. By doing so we are able to establish a remote base camp area that allows us to work autonomously for weeks at a time. However, base camp life can take its toll and we generally have limited ourselves to 2-week stints in the jungle. In the case of Sian Ka’an, we are fortunate that we have been able to stay at the Centro de Visitantes de Sian Ka’an a visitors center built expressly for researchers. As a result, we have been able to spread the project out over 5 months for an average of 5 days of exploration each outing. Another benefit is that the primary entrances to the northern and southern caves of Sian Ka’an are actually in lakes. Therefore, in order to get to the dive sites we merely load a boat with equipment and, in either case, have a 10-minute boat ride to the cave entrance.

20 The real challenge is once the divers are in the water. Although the project in Sian Ka’an presents our dive team with easy logistics to reach the cave entrance, it presents significant challenges as soon as they hit the water. One of the first things that divers encounter in Entrada Caapechen is extreme water flow. In fact, the flow is so strong that a fully loaded diver has to kick in addition to being pulled by a scooter to advance the first 100 meters of the cave. Although flow gradually dissipates as the divers travel further back into the cave, it is still stronger, overall, than has been seen in any cave in this area. On more than one occasion, the flow reduced the visibility dramatically within the first 100 meters of the cave. This affected dive planning and safety measures for each dive that was done.

The other challenge for the divers is that, so far, Entrada Caapechen, the main cave in Sian Ka’an, only has one entrance. The majority of cave systems in this area have multiple entrances, in fact, in order to be called a cave ‘system’, a cave must have more than one entrance. In the case of Ox Bel Ha, there are close to 100 entrances to the cave spread over 144 kilometers of cave, meaning that on average you should find an entrance every 1.5 kilometers. Multiple entrances have two immediate benefits. First, they provide extra security as a ‘bailout’ should a diver experience equipment failure or any other type of problem. Psychologically it is very comforting to know that air is always nearby. Second, they provide a point from which divers can enter to continue exploring, effectively allowing us the ‘leap frog’ from entrance to entrance moving further and further back. Having only one entrance requires additional safety measures. In this case additional SCUBA tanks were left inside the cave to insure that the dive team had additional bailout, on top of the air they carried with them. When one considers that the lead divers on this project are pushing more than 3 kilometers back in two different directions, only then does the enormity of the dives being undertaken (over 6 kilometers roundtrip) begin to sink in.

Despite all of the challenges, the divers and all of those who supported them at the surface for this project rose to the task at hand. In particular, Fred Devos, Christophe Le Maillot, Daniel Riordan and Per Thomsen deserve so much credit for the incredible effort they have put forth to explore and map the caves on this project.

Diving Procedures The Mexico Cave Exploration Project is a Global Underwater Explorers affiliate and is supported by GUE training, diving logistics, and administrative support. We share a desire to safely explore and protect the underwater world and to improve the quality of education and research in all things aquatic. MCEP subscribes to a team approach in diving and we work throughout the year training, practicing and gaining experience. With years of local cave exploration experience and access to an international base of highly skilled divers we are able to align the support needed to safely and efficiently conduct mission specific dives in some of the most challenging underwater cave environments. The equipment we utilize is designed for quality and performance and is configured as a standardized system. This uniformity between divers is critical during such team projects often located in remote areas. Breathing gas choices and gas management are also

21 standardized with special emphasis placed on avoiding diving maladies such as oxygen toxicity.

Figure 13

The standardized procedures we utilize are based in prevention and efficient management during emergencies. In addition to these procedures and redundant underwater life support equipment, we establish above-water support for dealing with emergencies. The environments we dive in are often pristine and all effort is employed to minimize the effects to that environment. Dive plans, equipment, procedures and techniques all strive to leave the environment in the same way it was found.

Cave Survey and Cartographic Methods It is the collective interest of CINDAQ AC and MCEP to survey and document new and existing underwater caves and to make this data available to groups legitimately trying to better understand caves and their related elements. For many years we have been shaping our survey methods in order to efficiently provide clear and concise data that is of optimal use to a wide range of end users whether they be cartographers, landowners, scientists or developers.

Survey of the caves is conducted using knotted line, compass and digital depth gauges. All information gathered underwater is recorded on underwater slates. Survey for this project was conducted on the way into the cave in order to decrease time pressure and increase accuracy and safety.

In addition, a standardized data collection sheet (Table 1) was filled out by divers during each dive to record the following information: Passage width (meters), Passage Height (meters), Passage Shape, Fauna, Speleothems, Sediment, Infill and Water characteristics. This along with high-resolution photographs and video footage provide a clear sense of the sub-aquatic cave. In addition to these general observations, we can tailor the data collection and our dive planning to include elements of interest to a specific end-user.

Standardized data collection slates Table1

Upon surfacing, survey data were transferred to Microsoft Excel spreadsheets and all dive slates were scanned so that a digital copy of the original slate exists. These spreadsheets and scans are presented in this report. Data was then entered into Compass, computer software designed specifically for the mapping of caves. From Compass, line maps were then exported as shapefiles into ArcView 3.1 GIS and overlaid on geo referenced aerial and satellite images. In ArcView, both data collected underwater and on the surface can then be compared. To elaborate the maps presented in this report, the particular areas being mapped were exported from either Compass or ArcView to Adobe Illustrator where the map was made. CINDAQ thanks both Jim Coke and Fred Devos for their help in preparing survey data for this project. Fred Devos, Dr. Patricia Beddows and Simon Richards developed the standardized data collection sheets.

Surface Mapping This project saw the use of state of the art GPS technology for the first time to help us effectively and efficiently locate and assess cenotes and navigate our way through the maze of channels and canals found in the Northern Boundary area of the SKBR. The Tripod Data Systems RECON uses a Pocket PC platform, proprietary software and GPS integration that allows unequaled accuracy in the field to locate and then document whatever it is we come across. The Holux GM-270 GPS reciever provides 2–5 meter accuracy using an internal antenna. All data were recorded using WGS84 datum for zone 16. By uploading geo referenced aerial and satellite imagery into the RECON, the guess

23 work is taken out of surface exploration as we always know exactly where we are in relation to whatever we are looking for. In addition, the ability to create custom attribute menus in the SOLO Office proprietary software permits us record information in the field much more efficiently and to manage it better.

Figure 14

Furthermore, by uploading shapefiles of explored cave passageways into the unit, we were able for the first time to accurately position ourselves above the cave at the surface. This came in useful when performing the conductivity studies with the Technical University of Denmark. All data were exported directly from the RECON as shapefiles and into ArcView 3.1. Specific areas of interest were exported from ArcView into Adobe Illustrator to produce the maps submitted in this report. It is our hope to continue to build custom attribute menus so that we can maximize data collection on future projects in the SKBR and elsewhere in the region.

Results of this Project From November 2005 to June 2006 teams of both surface and underwater explorers focused their efforts on the northern boundary areas of the SKBR. Surface exploration was aided by the study of aerial and satellite imagery of the area which was then uploaded into a highly sophisticated GPS device allowing for pinpoint accuracy for locating and documenting surface features. As a result, seven potential cenote entrances were identified, located and assessed for diving potential. Of these seven entrances one was found to have cave passageway large enough to allow a diver to pass through. As a by-product of surface exploration, abundant wildlife was observed throughout the area and recorded. Of note were tracks of a puma adult and cub close to the northern shore of Laguna Caapechen, and a healthy population of at least three if not five manatees were observed and documented with regularity at Entrada Caapechen. Marine fish species were observed well inland in seemingly landlocked cenotes. By combining information

24 shared by the Fédération Française de Spéléologie with local knowledge we were able to locate and assess five cave entrances within Lagunas Caapechen and Boca Paila. Working out of the Sian Ka’an Visitors Center we had easy access by boat to all entrances making the logistics easy when compared to previous projects. One additional cave entrance was found through surface exploration, unfortunately it is too restricted for a diver to enter. A total of 37 dives were performed between February and June of 2006 resulting in the resurvey, exploration and mapping of close to seven thousand meters of cave within the SKBR. Two of the entrances, Entradas Caapechen and Boca Paila revealed major flow of water and significant cave passageways that indicate that a massive cave system exists beneath the SKBR. The largest of the caves explored, Entrada Caapechen now extends two kilometers west from its entrance and contains just over six thousand meters of surveyed passageway.

Figure 15

Detailed observations were made both in the cave and on the surface to compliment and enhance our understanding of the hydrological and biological dynamics of this sensitive area. Surface conductivity studies were carried out by a team of scientists from the Technical Institute of Denmark, and data on water chemistry were collected by divers and interpreted by hydrologists working with the Center for Water Studies in Cancun. The preliminary results of these studies are submitted with this report. Both studies allowed our team to improve on the skills necessary for working both above and below the water with scientists. Video and photographic documentation was made of the cave and surface features explored on this project. In March, CINDAQ was included by the municipal government in round table talks to discuss the future development plans of Tulum and was able to make a strong case for the protection of the submerged cave systems in this area. Preliminary indications are that the Municipality is listening and is willing to consider low density development on top of any cave system in the area of the Tulum Development plan. While there is plenty of work to be done, this is an encouraging sign.

Future work in this area There are four main areas in the Northern Boundary Area of the SKBR that warrant further investigation. Both Entradas Caapechen and Boca Paila show great promise for further exploration. There is still plenty of work to be done using open circuit SCUBA at

25 both of these entrances. However, future projects could benefit from the use of either fully closed or semi-closed circuit rebreathers. This will extend the range of divers and greatly reduce the large quantity of tanks now required by divers to safely enter and exit the caves making logistics much easier. Moreover, with their greater efficiency, rebreathers will cut costs in the long run as less tanks need to be filled. As surface exploration revealed on this project, the ‘Gem’ Cenote group has one cenote with apparent cave exploration potential. Due to its strategic positioning which places it in line with the exploration lines heading west from Entrada Caapechen it is a high priority for future exploration. Before committing to a base camp project, it is recommended that a reconnaissance dive be preformed. Should it be deemed worthy of a full-blown expedition base camp, the only way possible to accomplish it will be with helicopter support. The last area of interest is a group of large cenotes located in the Zona Nucleo of the SKBR. They are strategically located to the 7 kilometers west of Entrada Boca Paila. Before diving can take place there they need to be thoroughly investigated from the surface. There is also limitless scientific work to be done both underwater and on the surface. We are willing and very able to coordinate and facilitate through our projects further scientific study of this complex area.

Cenotes in the Zona Nucleo (photo Sam Meacham) Figure 16

November 2005

Surface Exploration November 27th, 2005

Team: Roberto Chavez Arce, Sam Meacham, Simon Richards

Equipment used: TDSWay RECON GPS, Midland Radios, Suunto M3 compass, topographical maps, hard copy of aerial photographs, Nokia cel phone, Olympus 4040C camera, modified side- mount SCUBA gear with Pony bottles.

Area of work: Northern Sian Ka’an Boundry Limit (see map)

Objectives: • Locate and assess the ‘Gem’ Cenote group with small SCUBA tanks for a rapid assessment dive to see if cave exists. • Assess access to the ‘Gem’ Cenotes for possible future base camp

Access: Area was accessed by way of the Chunyaxche-Boca Paila canalway with the cooperation of the Camaal family. We were deposited at the northern tip of the canal near Cayo Venado. From this point it was a 1.5 kilometer hike through low mangrove, high water and mud.

Summary of results: We were able to reach the western most collapse area of the ‘Gem’ cenotes. From the aerial photos it appeared that they were two distinct collapse areas, in reality it is one big collapse area. Upon arrival Simon Richards donned modified SCUBA gear to perform a quick reconnaissance dive. Unfortunately no obvious cave entrances were found. Access is extremely difficult. If a base camp is to be established it needs to be done with helicopter support.

Wildlife observed: Very little surface wildlife was observed most likely due to Hurricane Wilma passing through this area only one month before. A variety of freshwater fish were observed within the cenote.

Possible Followup: Still need to check the 3 other collapse areas.

Comments: Surface water flow was observed moving west to east. In some areas water levels reached 50 centimeters. The excessive surface water can be attriburted to heavy rainfall associated with Hurricane Wilma.

Overview of area of surface exploration November 27th, 2005

Detail of surface exploration November 27, 2005, photos markers correspond to the photos on the following page

Satellite image of 'Gem' Cenotes The large collapse with sky blue water was the one that was dove

Aerial image of the Chunyaxche/Boca Paila Canal

Roberto and Simon make their way to the target. Note high water levels

Sam records points along the northern boundary line Simon upon returning from his recce dive

February 2006

Surface Exploration February 7th-8th, 2006

Team: Sam Meacham

Equipment used: TDSWay RECON GPS, Midland Radios, Suunto M3 compass, topographical maps, hard copy of aerial photographs, Nokia cel phone, Olympus 4040C camera

Area of work: Northern Sian Ka’an Boundary Limit (see map below)

Objectives: • Scout the area between Entrada Caapechen and the Ox Bel Ha Cave System • Record corner points on northern boundary line • Observe and record wildlife • Assess surface conditions and presence of cenotes in the area above the Arizona Line Access: Kayak from Entrada Camaron to northern shore of Lake Caapechen Walking

Wildlife observed: • Osprey • Puma tracks in several areas • Raccoon tracks in several areas • Deer or wild pig tracks • Large bird colony to the northeast of Entrada Camaron located on mangrove island

Summary of results: • Three corner points from the northern boundary recorded • Tracks of top predator observed with possible offspring • Able to navigate to surface point above a specific target within the cave

Possible Followup: • Need to return to continue along trail heading northwest • Good place for remote camera to monitor Puma movements

Comments: Terrain is difficult in areas due to thick mud near the lake and thick vegetation further inland. Areas of open rock are easy to navigate.

Overview of area of surface exploration February 7th-8th, 2006

Detail of surface exploration February 7th-8th, 2006, photos markers correspond to the photos on the following page

Puma print Open area above Arizona Line

Raccoon print Corner point of boundary line

Puma print Raccoon print

36 Diving Operations February 7th, 2006

Dive Team: Fred Devos, Andrea Marassich

Surface Support: Aldo Ancona, Sigurd Bowitz, Sam Meacham

Dive site #1 Name: Entrada Camaron Coordinates: UTM (WGS 84): 16Q 448230 2223587

Conditions: Strong flow at entrance which dissipates quickly with cave widening and getting deeper.

Dive site #2 Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: The water condition improves at 7m (20ft) from the murky Laguna water to clear 30m (100ft) + visibility. The Cave immediately drops to 12m (40ft). Very high flow of water and sharp rocks on walls and ceiling. Thick gel-like sediment on floor.

Dive Objectives: 1. Survey and assess original French Line in Entrada Camaron 2. Continue Exploration with emphasis in the direction of Ox Bel Ha 3. Assess Entrada Caapechen (Cenote Manati)

Summary of results: 1. Conducted 3 short dives replacing French line buried in silt. 2. Established “Shrimp Cocktail” Line upstream and “Silt Clog” Line downstream. 3. Made reconnaissance dive in Entrada Caapechen. Extreme flow made entry difficult. Scooters are needed for further penetration.

Possible follow up: 1. Need to return to explore leads in both entrances.

Comments/observation:

Line name: Shrimp Cocktail Passage width (meters): 10 Passage Height (meters): 2 Passage Shape: Flat ceiling Fauna: Lots of Shrimp, amphipods

37 Speleothems: Orange, stalactites, stalagmites, fossils Sediment: Light Brown, organic,percolation Infill: Water: Halocline near floor Additional Comments:

Comments/observation:

Line name: Silt Clog Passage width (meters): 7 Passage Height (meters): 1 Passage Shape: Flat Ceiling Fauna: Tarpon, Shrimp Speleothems: Orange, stalactites Sediment: Light brown, organic, flat, percolation Infill: Water: Freshwater only Additional Comments: Tarpon in downstream entrance of Entrada Camaron, deep crack in the floor. Abundance of shrimp upstream in Entrada Camaron.

Equipment and Survey: Single stage used (switched out between dives) and back gas as reserve. Surveyed out of cave due to need of cutting away existing line.

Dive log:

Dive # 1 Dive # 2 Dive # 3 (Camaron) (Camaron) (Caapechen) Time in: 10h58 Time in: 12h28 Time in: 12h28 Time out : 12h11 Time out: 12h58 Time out: 12h58 Total run time: 73 minutes Total run time: 30 minutes Total run time: 17 Max Depth: 47 feet Max Depth: 21 feet minutes Av Depth: 30 feet Av Depth: 17 feet Max Depth: 43 feet Total Exploration: 475 feet Total Exploration: 115 feet Av Depth: 25 feet Divers: Fred, Andrea Divers: Fred, Andrea Total Exploration: - Line Names: “Shrimp Cocktail” Line Names: “Silt Clog” Divers: Fred, Andrea Line Names: -

38 39 Entrance Entrada Camaron Line Name Shrimp Cocktail Date 9-Feb-06 Explored Explored By Fred Devos, Andrea Marassich Surveyed By Fred Devos Tie in Line begins Compass SKASC Station here prefix

MAX Depth in Feet 47 MIN Depth in Feet 9 Total Dist in Feet 475

MAX Depth in Meters 14.24 MIN Depth in Meters 2.73 Total Dist in Meters 143.94

FROM TO Sta Depth DIST Azimuth COMMENTS tio (Feet) (Fee IN n# t) 0 0 1 1 9 60 240 START,DRIPLINE 1 2 2 14 66 246 SflowN,ORGANIC WALLS 2 3 3 17 22 202 SflowN,ORGANIC WALLS 3 4 4 13 42 222 FRENCH LINE CUT 4 5 5 13 29 209 5 6 6 13 33 213 6 7 7 19 24 204 CLEARWATER,ORGANIC PERCOLATION 7 8 8 21 52 232 !E!,>YC107 8 9 9 26 33 213 DECORATED 9 10 10 32 18 198 !NE!>YC108 10 11 11 31 49 229 11 12 12 30 21 201 12 13 13 36 20 200 13 14 14 46 6 186 NO FLOW 14 15 15 47 H,END,>YC106

40 Line Name Silt Clog Date 9-Feb-06 Explored Explored By Fred Devos, Andrea Marassich Surveyed By Fred Devos Tie in SKASC0 Compass SKACL Station prefix

MAX Depth in Feet 21 MIN Depth in Feet 9 Total Dist in Feet 115

MAX Depth in 6.36 Meters MIN Depth in Meters 2.73 Total Dist in Meters 34.8 5

FROM TO Stat Depth DIST Azimuth COMMENTS ion (Feet) (Feet) IN # 0 0 1 1 9 40 84 START,DRIPLINE 1 2 2 15 17 54 2 3 3 20 26 146 TARPON 3 4 4 21 32 216 !NNE!,DEEP CRACK 4 5 5 19 END,>YC110

42 Diving Operations February 8th, 2006

Dive Team: Fred Devos & Andrea Marassich

Surface Support: Julio, Sigurd Bowitz, Sam Meacham

Dive site Name : Entrada Camaron Coordinates: UTM (WGS 84): 16Q 448230 2223587

Conditions: Strong flow at entrance which dissipates quickly with cave widening and getting deeper.

Dive Objectives: 1. Continue Exploration, Survey and assessment of “Camaron”

Summary of results: 1. Established “Stag Ranch” Line upstream 2. Cleared Rocks from Deep Lead downstream 3. Checked all leads downstream 4. Established “Stag Loop” Line upstream.

Possible follow up: 1. Return to explore difficult downstream lead though risky and not promising.

Comments/observation:

Line name: Stag Ranch Passage width (meters): 7 Passage Height (meters): 1.5 Passage Shape: Bedding plane Fauna: A few shrimp Speleothems: Orange, stalactite, stalagmite, flowstone Sediment: Orange/brown, organic, flat, percolation Infill: Water: Brackish water Additional Comments: Line name: Stag Loop Passage width (meters): 7 Passage Height (meters): 2 Passage Shape: Bedding plane Fauna: Shrimp

43 Speleothems: Orange, stalactite, stalagmite, flowstone, fossils Sediment: Light brown, organic, flat, percolation Infill: Water: Brackish Water Additional Comments: Water flow seems to come from shallow ceiling cracks. Flow does not continue downstream. Heavy silt clogging deeper (no-flow) passages.

Equipment and Survey: Single stage per diver used (switched out between dives) and back gas kept as reserve. Surveyed into cave.

Dive log:

Dive # 4 Dive # 5

Time in: 11h45 Time in: 13h00 Time out : 12h43 Time out: 13h12 Total run time: 58 minutes Total run time: 12 minutes Max Depth: 31 feet Max Depth: 21 feet Av Depth: 25 feet Av Depth: 180feet Total Exploration: 275 feet Total Exploration: - Divers: Fred, Andrea Divers: Fred, Andrea Line Names: “Stag Ranch” Line Names: -

Dive # 6 Dive # 7

Time in: 13h33 Time in: 13h54 Time out: 13h52 Time out: 15h08 Total run time: 19 minutes Total run time: 74 minutes Max Depth: 40 feet Max Depth: 27 feet Av Depth: 30 feet Av Depth: 24 feet Total Exploration: - Total Exploration: 159 feet Divers: Fred, Andrea Divers: Fred, Andrea Line Names: - Line Names: “Stag Loop”

45 Line Name Stag Loop Date Explored 10-Feb-06 Explored By Fred Devos, Andrea Marassich Surveyed By Fred Devos Tie in Station SKASTR9 Compass SKASTL prefix

MAX Depth in Feet 27 MIN Depth in Feet 20 Total Dist in Feet 159

MAX Depth in Meters 8.18 MIN Depth in Meters 6.06 Total Dist in Meters 48.18

FROM TO Stati Depth DIST Azimuth COMMENTS on# (Feet) (Feet) IN 0 0 1 1 20 18 198 START,>YC104 1 2 2 24 13 193 2 3 3 26 10 190 3 4 4 26 9 189 4 5 5 27 25 320 5 6 6 25 22 202 6 7 7 24 27 207 7 8 8 21 35 215 8 9 9 20 END,T,JUMP

46 Line Name Stag Ranch Date Explored 10-Feb-06 Explored By Fred Devos, Andrea Marassich Surveyed By Fred Devos Tie in Station SKASC9 Compass SKASTR prefix

MAX Depth in Feet 31 MIN Depth in Feet 20 Total Dist in Feet 275

MAX Depth in Meters 9.39 MIN Depth in Meters 6.06 Total Dist in Meters 83.33

FROM TO Sta Depth DIST Azimuth COMMENTS tio (Feet) (Feet) IN n# 0 0 1 1 20 26 154 START,>YC107 1 2 2 24 30 201 2 3 3 24 25 173 3 4 4 31 43 94 NEAR>YC108 4 5 5 31 31 48 v^v^v 5 6 6 26 35 141 v^v^v,(STAGLOOP END) 6 7 7 24 27 82 v^v^v 7 8 8 24 31 340 SflowN 8 9 9 27 27 69 9 10 10 20 END,!N!,>YC104

48 Diving Operations February 9th, 2006

Dive Team: Fred Devos, Jarrod Jablonski & Per Thomsen

Surface support: Daniel Riordan

Dive site #1

Name: Entrada Caapachen (Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: The water condition improves at 7m (20ft) from the murky Laguna water to clear 30m (100ft) + visibility. The visibility in the cave is generally good on the way in especially for the lead diver. There is heavy percolation (debris falling from the ceiling), reducing visibility for divers following the leader. Strange bacterial growth covers a lot of the caves walls. It seems to stretch under its own weight and creates shapes that resemble speleothems. Water flow seems to come from the SW/W&NW. The flow can be very substantial for the first 30 meters (100 ft) of the cave. The water temp is warmer in the fresh water: 26˙C (79˙F). The halocline sits at 16.67m (55ft).

Dive site #2

Name: Oxpechen 1 Coordinates: UTM (WGS84): 16 Q 448288 2221179

Conditions: The water condition is clear 30m (100ft) + visibility although heavy perculation noted in deeper areas. Flow dissipates with penetration and increased depth.

Dive Objectives: 1. Survey and assess original French Line in Caapechen 2. Continue Exploration in Caapechen 3. Assess the Oxpechen 1 Entrance 4. Video document the cave

Summary of results: 1. Replaced French line buried in silt 2. Established “French Flow 1” and “Orange Pekoe” Line in Caapechen. 3. Established “Kaapechen (Oxpechen) ML” in Oxpechen 1 4. Video documented both caves

Possible follow up:

49 1. Lots of promise for further exploration in Caapechen. 2. Original French line should be removed. 3. Line heading NE from Oxpechen 1 opening should be investigated.

Comments/observation:

Line name: French Flow Passage width (meters): 10-20 Passage Height (meters): 5 Passage Shape: Canyon, ,Flat ceiling, Dome, Bedding plane Fauna: @50 Cubera snappers in cenote entrance Speleothems: Brown, stalactite, stalagmite Sediment: Red/white, organic, organic percolation Infill: Mung Water: Halocline near floor Additional Comments: Parts of the cave wall are pure white limestone

Comments/observation:

Line name: Orange Pekoe Passage width (meters): 10-20 Passage Height (meters): 5 Passage Shape: Canyon, ,Flat ceiling, Dome, Bedding plane Fauna: Speleothems: Brown, stalactite, stalagmite Sediment: Red/white, organic, organic percolation Infill: Mung Water: Halocline mid passage Additional Comments: Parts of the cave wall are pure white limestone Flow dissipates slightly as cave becomes larger with penetration. Thick orange sediment on ceiling and walls is easily disturbed by bubbles and creates visibility problems. Strange dreadlock-like sediment hanging in ropes from ceiling and walls.

Comments/observation:

Line name: Main Line (Entrada Oxpechen 1) Passage width (meters): 10 Passage Height (meters): 5 Passage Shape: Undercut Floor Fauna: Lots of shrimp Speleothems: Orange, stalactites, stalagmites, flowstone Sediment: Grey, organic, flat, percolation

50 Infill: Breakdown Water: Halocline near floor Additional Comments: Flow of water comes from no-mount crack in ceiling. Deeper (no flow) cave is clogged with sediment.

Equipment and Survey: 2x stages, back gas as reserve and 1 x 33amp scooters per diver. Knotted line was laid over existing French line buried in silt. Survey and video was done on the way in using scooters.

Dive log:

Dive # 8 Dive # 9 (Caapechen) (Oxpechen 1) Time in: 11h54 Time in: 15h10 Time out: 13h34 Time out: 16h34 Total run time: 100 minutes Total run time: 84 minutes Max Depth: 55 feet Max Depth: 57 Av Depth: 50 feet Av Depth: 40 Total Exploration: 1,432 feet Total Exploration: 561 feet Divers: Fred, Per, Jarrod Divers: Fred, Per, Jarrod Line Names: “French Flow”, “Orange Line Names: “Kaapechen (OPC 1) ML” Pekoe”

52 53 Line Name French Flow Date Explored 9-Feb-06 Explored By Per Thomsen, Jarrod Jablonski, Fred Devos Surveyed By Fred Devos Tie in Station Line begins here Compass CMMLR0 prefix

MAX Depth in Feet 46 MIN Depth in Feet 22 Total Dist in Feet 733

MAX Depth in Meters 13.94 MIN Depth in Meters 6.67 Total Dist in Meters 222.12

FROM TO St Depth DIST Azimuth COMMENTS at (Feet) (Feet) IN io n # 0 0 1 1 22 75 270 CENTER OF CENOTE 1 2 2 36 22 19 START OF LINE 2 3 3 39 12 329 3 4 4 39 26 308 4 5 5 39 36 295 5 6 6 38 27 295 6 7 7 40 32 288 7 8 8 40 34 306 8 9 9 40 41 296 9 10 10 38 45 270 !N! >YC103 10 11 11 40 40 296 11 12 12 39 27 278 12 13 13 42 57 307 >SK 2006 #11,JUMP TO "RUSSIA" 13 14 14 44 55 291 14 15 15 41 44 318 15 16 16 43 24 336 T,>YC101 16 17 17 41 30 3 17 18 18 37 34 36 DOME,v^v^ 18 19 19 29 25 323 19 20 20 38 47 80 20 21 21 46 END,>YC102 21 22 22

Line Name Orange Pekoe Date Explored 9-Feb-06 Explored By Per Thomsen, Jarrod Jablonski, Fred Devos Surveyed By Fred Devos Tie in Station CMMLR17 Compass CMMLR (Orange prefix Pekoe and French Flow joined in compass due to resurvey

MAX Depth in Feet 55 MIN Depth in Feet 33 Total Dist in Feet 699

MAX Depth in Meters 16.67 MIN Depth in Meters 10.00 Total Dist in Meters 211.82

FROM TO S Depth DIST Azimuth COMMENTS t (Feet) (Feet) IN a ti o n # 0 0 1 1 42 58 250 START,>YC101 1 2 2 42 34 280 2 3 3 33 81 296 3 4 4 44 90 256 H 4 5 5 44 101 240 H 5 6 6 47 34 264 6 7 7 48 43 234 7 8 8 55 48 248 8 9 9 50 47 288 9 10 1 44 93 288 0 10 11 1 46 50 347 1 11 12 1 53 20 38 2 12 13 1 47 END,BIG 3 STAG,>YC109

57 Diving Operations February 10th, 2006

Dive Team: Fred Devos, Jarrod Jablonski & Per Thomsen

Surface Support: Julio

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: Strong flow again at the entrance.

Dive Objectives: 1. Continue Exploration 2. Video document the cave

Summary of results: 1. Explored and surveyed “French Flow 2” Line. 2. Video documented cave.

Possible follow up:

1. Lots of promise for further exploration. 2. French line near entrance must be removed. 3. “Frenchflow 1” line should be re-surveyed when flow is reduced.

Comments/observation:

Line name: French Flow 2 Passage width (meters): 10 Passage Height (meters): 4 Passage Shape: Phreatic tube, Verticle fracture, Dome, Flat ceiling Fauna: Speleothems: Orange, stalactites, stalagmites, flowstone Sediment: Orange, organic, ripples, percolation Infill: Water: Halocline near the floor, Additional Comments: White solid limestone, video of this passage was taken on this dive. Warm brackish water flowing NW to SE in defined 12m (40ft) passage.

Equipment and Survey:

58 2 stages and 1 x 33amp scooter per diver. 1 x 18 amp scooter carried as safety. It took 10 minutes to scooter to begin of exploration. Survey and video was done on the way in, using scooters.

Dive log:

Dive # 10

Time in: 11h30 Time out : 14h30 Total run time: 120 minutes Max Depth: 66 feet Av Depth: 54 feet Total Exploration: 2,162 feet Divers: Fred, Per, Jarrod Line Names: “French Flow 2”

59 60

Line Name French Flow 2 Date Explored 10-Feb-06 Explored By Per Thomsen, Fred Devos, Jarrod Jablonski Surveyed By Fred Devos Tie in Station CMMLR31 Compass CMFFF prefix

MAX Depth in Feet 66 MIN Depth in Feet 20 Total Dist in Feet 2162

MAX Depth in Meters 20.00 MIN Depth in Meters 6.06 Total Dist in Meters 655.15

FROM TO Sta Depth DIST Azimuth COMMENTS tio (Feet) (Feet) IN n# 0 0 1 1 51 20 285 T,BIG STAG,>YC109 1 2 2 49 31 334 2 3 3 48 40 279 3 4 4 47 67 276 4 5 5 47 45 257 5 6 6 52 26 241 6 7 7 48 25 210 7 8 8 50 30 269 8 9 9 46 20 295 NWflowSE,!SE! 9 10 10 46 60 305 10 11 11 47 28 1 11 12 12 47 12 343 12 13 13 50 46 290 13 14 14 62 42 16 v^v^v 14 15 15 64 52 338 v^v^v 15 16 16 66 35 355 16 17 17 64 20 340 17 18 18 53 29 349 18 19 19 52 29 287 H 19 20 20 39 44 287 20 21 21 20 75 253 21 22 22 30 28 324 22 23 23 28 50 255

61 23 24 24 26 30 250 24 25 25 30 55 250 25 26 26 47 47 301 STAGE DROP 26 27 27 50 54 262 27 28 28 49 26 310 28 29 29 49 45 320 NWflowSE 29 30 30 51 44 274 H 30 31 31 64 55 302 31 32 32 59 92 292 v^v^v 32 33 33 51 25 251 33 34 34 53 18 250 34 35 35 51 50 256 35 36 36 43 45 325 36 37 37 39 25 312 37 38 38 29 34 302 38 39 39 26 40 324 R 39 40 40 26 41 335 R 40 41 41 24 40 344 41 42 42 28 56 14 42 43 43 37 47 316 43 44 44 39 26 310 v^v^v 44 45 45 44 38 295 45 46 46 42 12 262 46 47 47 41 42 280 47 48 48 40 32 218 48 49 49 40 80 290 49 50 50 57 53 316 H,NWflowSE 50 51 51 47 54 290 NWflowSE 51 52 52 46 51 284 52 53 53 45 51 291 53 54 54 49 END,!NW!,>YC705 54 55 55

March 2006

64 Diving Operations March 23rd, 2006

Dive Team: Fred Devos & Chris Le Maillot

Surface Support: Esteban

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: The wind was blowing from the East. Surface was choppy. Little flow felt at the entrance. Is this related to wind direction? There’s a big school of dog and cubera snappers patrolling the sunken sink hole. Remoras are part of the pack too.

Dive Objectives: 1. Remove existing French lines (they are encrusted with organic matter) 2. Continue exploration from the end of the French Flow 2 Line

Summary of results: 1. Retrieved most of the French lines. There’s more line to remove 10 minutes in at the right side of T. Lines were buried in silt in some areas. 2. Additional 1,100 feet of cave passage found and surveyed at the end of “French Flow 2”. There is big cave to the SW. Steady flow is coming from the NW. Big dome areas are decorated. 3. Explored first lead at the end of “French Flow 2” for 350 feet. This is of particular interest as the cave drops to 100 feet. Speleothems were observed at that depth.

Possible follow up: 1. Extend the exploration of the end of line at 4,579 feet. There’s a big NW lead with inviting flow there. 2. Check on the dome areas for SW leads 3. Probe the many N leads 4. Replace French line at the right of first T junction.

Comments/observation:

Line name: French Flow 3 Passage width (meters): 10 Passage Height (meters): 4 Passage Shape: Undercut Floor Fauna: Shrimp; remoras and snappers in entrance Speleothems: Brown, stalactites, stalagmites

65 Sediment: Orange, organic, ripples, flat, percolation Infill: Water: Halocline mid passage Additional Comments: Observed less flow at beginning of dive that increased over time.

Comments/observation:

Line name: North Hope Passage width (meters): 10 Passage Height (meters): 6 Passage Shape: Undercut floor, Vertical Fracture Fauna: Shrimp Speleothems: Brown, stalactites, stalagmites Sediment: Orange, organic, ripples, percolation Infill: Water: Halocline mid passage Additional Comments:

Equipment and Survey: 3stages and 2 scooters per diver (1 x 33amp + 1x 18amp). The first stage was kept in the cave with 2000psi of gas. It took 25 minutes to scooter to the end of “French Flow 2”. The 18amp scooter was used as a back up. Survey was done on the way in. This is a better method of survey as there’s plenty of gas for exit and no unnecessary time pressure.

Dive Log:

Dive # 11 Dive # 12

Time in: 12h00 Time in: 13h15 Time out : 12h55 Time out: 15h35 Total run time: 55 minutes Total run time: 145 minutes Max Depth: 55feet Max Depth: 101 feet Av Depth: 45 feet Av Depth: 50 feet Divers: Fred & Chris Total exploration: 1450 feet Line Names: Divers: Fred & Chris Line Names: “North Hope”, “North Hope Tie in”, “French Flow 3”

66 67 Line Name French Flow 3 Date Explored 23-Mar-06 Explored By Christophe and Fred Surveyed By Fred Tie in Station CMFFF53 Compass CMFFFF prefix

MAX Depth in Feet 92 MIN Depth in Feet 51 Total Dist in Feet 346

MAX Depth in Meters 27.88 MIN Depth in Meters 15.45 Total Dist in Meters 104.85

FROM TO Stati Depth DIST Azimuth IN COMMENTS on# (Feet) (Feet) 0 >YC 705 START 0 1 1 51 40 284 v^v^v 1 2 2 55 75 290 v^v^v 2 3 3 56 65 296 3 4 4 60 38 290 4 5 5 62 72 251 5 6 6 70 56 172 v^v^v 6 7 7 92 CONT. TO 100FT DEPTH

Line Name North Hope Date Explored 23-Mar-06 Explored By Christophe and Fred Surveyed By Fred Tie in Station CMFFF53 Compass CMFNH prefix

MAX Depth in Feet 57 MIN Depth in Feet 32 Total Dist in Feet 1105

MAX Depth in Meters 17.27 MIN Depth in Meters 9.70 Total Dist in Meters 334.85

FROM TO Station# Depth DIST Azimuth IN COMMENTS (Feet) (Feet) 0 >SK 03-06#4,JUMP 0 1 1 55 66 344 NflowS,v^v^v 1 2 2 56 44 4 NflowS,v^v^v 2 3 3 57 29 72 3 4 4 54 40 34 4 5 5 46 64 18 5 6 6 48 65 5 DOME 6 7 7 39 59 328 DOME 7 8 8 32 86 271 DOME 8 9 9 32 86 255 DOME 9 10 10 34 44 270 DOME 10 11 11 36 45 250 11 12 12 45 40 276 12 13 13 52 60 272 SWflownNE 13 14 14 55 30 217 14 15 15 54 15 250 15 16 16 48 38 231 16 17 17 43 39 252 !SW! 17 18 18 41 55 284 WflowE 18 19 19 45 37 262 19 20 20 56 36 250 20 21 21 52 24 276 !WSW! 21 22 22 48 67 338 NWflowSE 22 23 23 51 36 337 !NW!,!NE!,NWflowSE,>SK O3- 06#5

69 Line Name North Hope Tie In Date Explored 23-Mar-06 Explored By Christophe and Fred Surveyed By Fred Tie in Station

MAX Depth in Feet 54 MIN Depth in Feet 50 Total Dist in Feet 100

MAX Depth in Meters 16.36 MIN Depth in Meters 15.15 Total Dist in Meters 30.30

FROM TO Station# Depth DIST Azimuth IN COMMENTS (Feet) (Feet) 0 >SK 03-06#4 0 1 1 54 100 40 >YC 705 1 2 2 50 2 3 3

71 Diving Operations March 24th, 2006

Dive Team: Alex Alvarez, Fred Devos & Chris Le Maillot.

Surface Support: Alex Alvarez

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: The wind was blowing from the North. Water surface was calm. Strong flow at the entrance. There is no flow in this area.

Dive Objectives: 1. Continue exploration from the end of the “North Hope” line 2. Remove the rest of the French line at the right of first T

Summary of results: 1. Additional 1,443 feet of line added to end of ‘North Hope”. The line stopped in a huge chamber heading W/NW with flow. 2. Successful removal of remaining French line. 3. Additional 300ft added in a bedding plane with halocline near bottom floor. There’s lots of organic sediment all around. Cave still goes NE. Barely noticeable flow. 4. First T cut back.

Possible follow up: 1. Extend the exploration of the end of line at 6,022 feet. There’s a big chamber with many speleothems there. 2. Check the SW leads. There is noticeable flow coming from the SW. 3. Probe the many N leads

Comments/observation:

Line name: Silica Dome Passage width (meters): 10 Passage Height (meters): 10 Passage Shape: Flat ceiling Fauna: Shrimp Speleothems: Brown, stalactites, stalagmites, fossils Sediment: White, black, clay, organic, percolation Infill: Breakdown Water: Halocline mid passage

72 Additional Comments: There’s a white dome 5,200 feet in at a depth of 35ft with no percolation and a thin white dusting over layer of red clay. The water temp is 81F.

Comments/observation:

Line name: French North Passage width (meters): 10 Passage Height (meters): 6 Passage Shape: Dome, Flat ceiling Fauna: Shrimp Speleothems: White, stalactites Sediment: Dark, organic, percolation Infill: Breakdown Water: Halocline near floor Additional Comments:

Equipment and Survey: 3stages and 2 scooters per diver (1 x 33amp + 1x 18amp). It took 32 minutes to scooter to the end of “North Hope”. The 18amp scooter was used as a back up. Survey was done on the way in.

Dive log:

Dive # 13 Dive # 14

Time in: 11h30 Time in: 14h45 Time out :14h15 Time out: 16h17 Total run time: 165 minutes Total run time: 92 minutes Max Depth: 70 feet Max Depth: 50 feet Av Depth: 57 feet Av Depth: 40 feet Total exploration: 1,443 feet Total exploration: 300 feet Divers: Fred & Chris Divers: Alex, Fred & Chris Line Names: “Silica Dome” Line Names: “French North”

74 75 Line Name Silica Dome Date Explored 24-Mar-06 Explored By Fred and Chris Surveyed By Fred Tie in Station CMFNH23 Compass CMFSD prefix

MAX Depth in Feet 68 MIN Depth in Feet 35 Total Dist in Feet 1443

MAX Depth in 20.61 Meters MIN Depth in Meters 10.61 Total Dist in Meters 437.27

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 50 42 280 >SK 03-06#5 1 2 2 50 38 332 2 3 3 50 35 12 3 4 4 55 9 74 v^v^ 4 5 5 55 83 34 v^v^,R 5 6 6 57 32 356 6 7 7 66 23 12 NO FLOW 7 8 8 64 30 50 NO FLOW 8 9 9 59 23 56 NO FLOW,H 9 10 10 56 39 351 NO FLOW 10 11 11 52 44 16 11 12 12 54 55 338 12 13 13 55 26 339 13 14 14 42 38 270 WARM DOME(81F) 14 15 15 35 51 290 WARM DOME(81F) 15 16 16 41 25 251 WARM DOME(81F) 16 17 17 46 31 264 H(FALSE) 17 18 18 56 50 246 18 19 19 57 19 266 NWflowSE 19 20 20 61 46 294 >SK 03-06#12,!E!,H 20 21 21 60 56 331 21 22 22 60 46 270 H,WflowE 22 23 23 56 61 238 23 24 24 58 44 239 WflowE,!SE! 24 25 25 64 25 224 !S! 25 26 26 60 40 292 26 27 27 65 38 215 27 28 28 63 40 232 28 29 29 62 19 332 29 30 30 60 49 339

76 30 31 31 56 33 310 31 32 32 64 51 11 32 33 33 61 28 347 33 34 34 63 37 316 34 35 35 68 47 292 35 36 36 64 55 14 PONG FORMATION 36 37 37 65 35 354 37 38 38 64 HUGE DOME,v^v^v,!SW!

77 Line Name French North Date Explored 24-Mar-06 Explored By Alex, Fred, Chris Surveyed By Fred Tie in Station CMMLR17 Compass CMFFN prefix

MAX Depth in Feet 48 MIN Depth in Feet 28 Total Dist in Feet 677

MAX Depth in Meters 14.55 MIN Depth in Meters 8.48 Total Dist in Meters 205.15

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 45 26 178 >YC 02-06#102 1 2 2 32 13 97 NEW LINE START 2 3 3 37 20 82 >YC 704 JUMP TO FRENCH LINE 3 4 4 39 41 87 4 5 5 44 46 41 5 6 6 43 46 352 6 7 7 45 49 53 7 8 8 48 39 98 8 9 9 44 43 53 9 10 10 31 18 41 10 11 11 28 18 40 11 12 12 30 102 43 FRENCH LINE ENDS 12 13 13 30 25 88 >SK 03-06#15,!N!,!NW! 13 14 14 44 30 20 14 15 15 47 18 75 15 16 16 46 54 22 16 17 17 46 89 124 GREY GOO 17 18 18 47 >SK 03-06#15,!NNE!

Diving Operations March 25th, 2006

Dive Team: Fred Devos & Chris Le Maillot, Luca Magheli

Surface Support: Gianmario Rocca

Dive site: Name: Entrada Caapechen (Cenote Manati) Coordinate: UTM (WGS84): 16 Q 449018 2220411

Conditions: The wind was blowing from the North again. Surface water conditions were calm. The flow was strong at the entrance. Is this re-enforcing the theory that wind direction is relevant to flow? Visibility in the entrance pool was 5ft. This is another change from the previous days of diving. The visibility cleared up at a depth of 35ft. Bottom timer recorded a water temp of 81F throughout the dive. The cave seems to be more open to the SW. The cave is large in some areas. Apart from the heavy layer of organic matters still covering the entire cave, the limestone underneath it is bleached white and solid. After hitting the ceiling and clearing it from organic sediment, the diver’s bubbles makes the white limestone more apparent. This is like having a marked trail on the roof of the cave.

Dive Objectives: 1. Continue exploration to the SW from ‘Silica Dome’ Line. 2. Further exploration near the entrance of the cave to the North.

Summary of results: 1. After a 35 minutes scooter ride, the team pushed SW a couple of stations after the end of “North Hope” (laid 23/03). An additional 1,305ft of cave was discovered and surveyed. 2. A second dive was conducted going N after a quick scooter ride on the ML (12 minutes). An additional 450 ft of line was laid in that direction. There’s a breakdown area that blocks any further progress N. As a result, the cave was swinging to the SE and will probably loop back to ML.

Possible follow up: 1. The end of the line laid today (Gandalf) is at 70ft and can still be pushed south. However, this is obviously not the main conduit. 2. There are big leads from “Gandalf” going SW/W that were marked during todays dive. This needs more investigation. 3. A SE lead from “Gandalf” was observed and needs to be checked soon.

Comments/observation:

Line name: Gandalf Passage width (meters): 5 Passage Height (meters): 4 Passage Shape: Canyon, Undercut Floor Fauna: Shrimp Speleothems: White, orange, stalactites, stalagmites Sediment: Brown, clay, ripples, percolation Infill: Breakdown Water: Halocline mid passage Additional Comments: Comments/observation:

Line name: Broken Passage width (meters): 10 Passage Height (meters): 2 Passage Shape: Bedding Plane Fauna: Shrimp Speleothems: White, orange, stalactites, stalagmites Sediment: Orange, clay, flat, percolation Infill: Breakdown Water: Freshwater only Additional Comments: Comments/observation:

Line name: Russia Line Passage width (meters): 3 Passage Height (meters): 1 Passage Shape: Bedding Plane Fauna: Speleothems: Sediment: Orange, white, flat, percolation Infill: Breakdown Water: Freshwater Only Additional Comments: Restricted, no flow

Equipment and Survey: 3 stages and 2 scooters per diver (1 x 33amp + 1x 18amp). The first stage was kept in the cave with 2000psi of gas. The 18amp scooter was use as a back up. Survey was done on the way in.

Dive log:

Dive # 15 Dive # 16

Time in: 11h00 Time in: 14h45 Time out :14h25 Time out: 16h17 Total run time: 205 minutes Total run time: 92 minutes Max Depth: 70 feet Max Depth: 50 feet Av Depth: 58 feet Av Depth: 42 feet Total exploration: 1,305 feet Total exploration: 542 Divers: Fred & Chris Divers: Luca, Fred & Chris Line Names: “Gandalf” Line Names: “Broken”, “Russia”

82 83

84 Line Name Gandalf Line Date Explored 25-Mar-06 Explored By Fred and Chris Surveyed By Fred Tie in Station CMFSD2 Compass CMFG prefix

MAX Depth in Feet 70 MIN Depth in Feet 40 Total Dist in Feet 1305

MAX Depth in Meters 21.21 MIN Depth in Meters 12.12 Total Dist in Meters 395.45

FROM TO Stati Depth DIST Azimuth COMMENTS on# (Feet) (Feet) IN 0 0 1 1 49 49 216 SECOND STATION AFTER… 1 2 2 46 33 204 2 3 3 48 32 206 3 4 4 54 80 204 4 5 5 56 32 198 5 6 6 50 38 286 6 7 7 40 72 194 !W! 7 8 8 45 45 155 8 9 9 54 30 236 >GLOWING,!SE! 9 10 10 53 44 248 10 11 11 54 37 170 >SK 2006 #22,!SW! 11 12 12 54 39 205 SEflowNW 12 13 13 50 27 174 SEflowNW 13 14 14 58 48 168 14 15 15 56 17 226 SWflowNE 15 16 16 49 23 238 16 17 17 42 30 257 17 18 18 43 75 259 18 19 19 47 51 186 >SK 2006 #19?,!W!,!NW! 19 20 20 49 77 203 20 21 21 51 29 252 21 22 22 56 42 198 v^v^ 22 23 23 57 22 230 SSWflowNNE 23 24 24 57 61 203 24 25 25 57 21 244 25 26 26 66 17 176 26 27 27 70 31 233 v^v^,WHITE

85 SEDIMENT 27 28 28 66 36 251 v^v^,WHITE SEDIMENT 28 29 29 56 32 198 >SK 2006 #20,!N! 29 30 30 62 59 161 GREEN GOO 30 31 31 54 12 55 31 32 32 55 24 80 32 33 33 69 40 215 v^v^ 33 34 34 62 SK 2006 #21,END

Line Name Russia Line Date Explored 25-Mar-06 Explored By Fred, Chris, Luca Surveyed By Fred Tie in Station CMMLR14 Compass CMFRL prefix

MAX Depth in Feet 43 MIN Depth in Feet 42 Total Dist in Feet 77

MAX Depth in Meters 13.03 MIN Depth in Meters 12.73 Total Dist in Meters 23.33

FROM TO St Depth DIST Azimuth COMMENTS ati (Feet) (Feet) IN on # 0 0 1 1 42 14 238 >SK 2006 #11,JUMP 1 2 2 43 37 203 START,>RUSSIA 2001 2 3 3 43 26 295 3 4 4 42 FRENCH LINE CONTINUES

Line Name Broken Line Date Explored 25-Mar-06 Explored By Fred, Chris, Luca Surveyed By Fred Tie in Station CMMLR31 Compass CMFBL prefix

MAX Depth in Feet 52 MIN Depth in Feet 29 Total Dist in Feet 465

MAX Depth in Meters 15.76 MIN Depth in Meters 8.79 Total Dist in Meters 140.91

FROM TO Stat Depth DIST Azimuth COMMENTS ion# (Feet) (Feet) IN 0 0 1 1 52 21 56 >YC 02- 06#109,START,JUMP 1 2 2 52 39 51 2 3 3 48 29 19 3 4 4 50 36 44 4 5 5 48 41 107 5 6 6 48 42 86 6 7 7 35 69 78 7 8 8 31 50 107 8 9 9 30 52 94 9 10 10 29 34 152 10 11 11 48 44 104 11 12 12 49 8 70 MILKY WATER 12 13 13 45 >SK03-06#9,END

April 2006

90 Surface Exploration April 6th-7th , 2006

Team: Sam Meacham, Christophe Le Maillot

Equipment used: TDSWay RECON GPS, Midland Radios, Suunto M3 compass, topographical maps, hard copy of aerial photographs, Nokia cel phone, Olympus 4040C camera

Area of work: Northern Sian Ka’an Boundary Limit (see map)

Objectives: • Navigate canal ways by kayak to closest point to ‘Gem’ Cenotes from Laguna Caapechen • Assess the remaining tree cenotes of the ‘Gem’ Cenotes for cave passageway • Assess access to the ‘Gem’ Cenotes from Laguna Caapechen • Confirm and record corner points of northern boundary line • Observe wildlife

Access: Kayaks were used to paddle through the canal ways of western Laguna Caapechen. From western most point of access by kayak to the ‘Gem’ Cenotes was made on foot. Canals are intricate but easy to navigate with the RECON. We had to walk @650 meters through mud and mangrove to the ‘Gem’ Cenotes. Walking access difficult.

Summary of results: We were able to locate the closest possible point to the ‘Gem’ Cenotes from Laguna Caapechen with no problem. One corner point of the boundary line was confirmed and recorded. The three remaining cenotes of the ‘Gem’ Cenote group were free dove and assessed. Of the three only one has diving potential. A massive crack was observed in the floor of this cenote with large cave passageway leading from it.

Wildlife observed: • Stingrays in canal • Herons • Roseate Spoonbills • Interesting marine fish observed in the seemingly landlocked cenotes

Possible Followup: We need to get a dive team into assess the one cenote with apparent going cave passage in order to see if a base camp is feasible.

Comments: The cenote with going passageway is perfectly aligned with Entrada Caapechen and the lines coming from it. It is a logical assumption to think that there is a connection here.

Overview of area of surface exploration April 6th-7th, 2006

Detail of surface exploration April 6th-7th, 2006, photos markers correspond to the photos on the following page

aerial view of Maya Temple, Laguna Caapechen navigating the canals by kayak

point from which we walked, 'Gem' Cenotes visible in background Cenote of the 'Gem' group

Cenote of the 'Gem' Group, this one appears to have Cenote of the 'Gem' Group, marine fish observed cave here

On the way back to the boat Mangrove and bromeliad in canal

94 Diving Operations April 5th, 2006

Dive Team: Alex Alvarez, Fred Devos & Chris Le Maillot

Surface Support: Esteban

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: The wind was blowing from the North. It was blowing North already for a few nights before that. Lagoon water was very clear. There was a strong flow at the entrance of cave. Flow at the entrance seemed stronger during afternoon dive.

Dive Objectives: 1. Drop 2 x safeties at 4k 2. Further exploration of the W/NW line 3. Go back to where “French lines” terminated and probe for more NW cave

Summary of results: 1. Dropped safeties OK at first T. 2. Additional 916’ feet (line name: Zig Zag) of cave passage found and surveyed at the end of “Silica Dome”. This is a big area with steady flow coming from the SW. Shallower domes at 40ft with speleothems always push exploration W/NW. Team had to go around decorated breakdown area. Good flow again and more promising cave at the end of line. 3. Additional 389’ (line name: Reversal) of cave explored from the end of “old French line”. This passage goes NW and is narrow. This is basically a giant fault that goes from 35ft ceiling to possibly 80ft at the bottom. There’s a noticeable flow from the NW. The end of the line is a no go. There’s a small lead 2 stations before end of line.

Possible follow up: 1. Continue exploring the end of “Zig Zag” W/SW. 2. Small lead can reveal interesting at the end of “Reversal”

Comments/observation:

Line name: Zig Zag Passage width (meters): 10 Passage Height (meters): 8 Passage Shape: Dome, Canyon Fauna: Shrimp, manatees, juvenile permit in entrance

95 Speleothems: Brown, white, stalactites, stalagmites, flowstone, fossils Sediment: Brown, organic, percolation Infill: Breakdown Water: Halocline near floor and mid passage Additional Comments: Ceiling of cave 6,000 feet in is white with little organic silt. Are we exploring under different soil? The depth of halocline has dropped from 45ft near the entrance to 55ft at around 3,000 feet in to 63feet at 6,000 feet.

Comments/observation:

Line name: Reversal Passage width (meters): 2 Passage Height (meters): 3 Passage Shape: Vertical fracture Fauna: Lots of shrimp Speleothems: Brown, flowstone Sediment: Brown, organic Infill: Water: Halocline near floor Additional Comments: Flow in salt water going NW. This was quite substantial as organic matters were moving rapidly.

Equipment and Survey: 3 stages and 2 scooters per diver (2 x 33amp). It took 42 minutes to scooter to first T & dropped safeties. Per “4” scooter is slow. Fred’s scooter needs brushes replacement. Survey was done on the way in. This is a better method of survey as there’s plenty of gas for exit and no unnecessary time pressure. Also, this is a better way to document cave

Dive log:

Dive # 17 Dive # 18

Time in: 12h30 Time in: 16h00 Time out : 15h45 Time out: 17h25 Total run time: 195 minutes Total run time: 85 minutes Max Depth: 69 feet Max Depth: 53 feet Av Depth: 58 feet Av Depth: 45 feet Total exploration: 916 feet Total exploration: 389 feet Divers: Fred & Chris Divers: Fred & Chris, Alex Line Names: “Zigzag” Line Names: “Reversal”

96 97 98 Line Name Zig Zag Date Explored 5-Apr-06 Explored By Fred and Chris Surveyed By Fred Tie in Station CMFSD37 Compass CMFZZ prefix

MAX Depth in Feet 64 MIN Depth in Feet 50 Total Dist in Feet 916

MAX Depth in Meters 19.39 MIN Depth in Meters 15.15 Total Dist in Meters 277.58

FROM TO St Depth DIST Azimuth COMMENTS at (Feet) (Feet) IN io n# 0 0 1 1 64 36 271 >SK #35,START 1 2 2 57 69 283 2 3 3 57 46 272 STAGE DROP 3 4 4 63 56 230 4 5 5 54 45 224 5 6 6 56 55 256 >SK #37!NW!, 6 7 7 59 73 209 7 8 8 60 43 285 8 9 9 63 33 219 H 9 10 10 60 37 272 10 11 11 61 46 349 11 12 12 60 86 338 12 13 13 60 47 260 13 14 14 58 65 251 14 15 15 51 23 188 15 16 16 50 11 244 16 17 17 55 33 237 17 18 18 60 49 227 18 19 19 57 27 227 19 20 20 56 36 234 20 21 21 59 END,>SK#41,Wflo wE

Line Name Reversal Line Date Explored 5-Apr-06 Explored By Fred, Alex, Chris Surveyed By Fred Tie in Station CMFFN10 Compass CMFRV prefix

MAX Depth in Feet 49 MIN Depth in Feet 28 Total Dist in Feet 389

MAX Depth in Meters 15 MIN Depth in Meters 8 Total Dist in Meters 118

FROM TO St Depth DIST Azimuth COMMENTS ati (Feet) (Feet) IN on # 0 0 1 1 28 55 340 START,>SK04- 06#43 1 2 2 36 15 290 2 3 3 35 36 260 3 4 4 40 30 320 4 5 5 45 28 29 5 6 6 43 8 290 6 7 7 46 36 260 7 8 8 47 23 0 8 9 9 46 33 270 9 10 10 44 40 340 10 11 11 44 6 30 11 12 12 45 22 310 12 13 13 49 17 275 13 14 14 45 23 358 14 15 15 42 17 260 15 16 16 46 END,>SK04-06 #44

100

101 Diving Operations April 6th , 2006

Dive Team: Alex Alvarez, Fred Devos, Chris Le Maillot, Per Thomsen

Surface Support: Esteban

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: The wind direction has changed to East. Lagoon water is still clear. There was a strong flow at the entrance of cave. Flow at the entrance seems stronger during afternoon dive.

Dive Objectives: 1. Further the exploration at the end of “Zig Zag” 2. Go back to old “French lines” area and tried out lead marked in March. 3. Collect silt sample

Summary of results: 1. Additional 1,204ft (line name: Shells) of cave passage found and surveyed at the end of “Zig Zag”. The cave was narrow just after breakdown area but gradually opened up to the SW. There’s a beautiful, well defined passage with good flow that leads to a canyon area. At this point the halocline is pined to the ceiling of the cave at a depth of 63ft. This area has a depth 73ft. The end of the line is back into the halocline. There is big SW and NW lead. 2. The exploration around old “French lines” added 2 different lines. “Dread Lock” off the “French North” line for 135ft of no viz exploration & “Orange Farm” at the end of “French North” for 202ft. The cave seems to keep running NE there but exploration is difficult due to organic “goo”. 3. Silt sample taken of organic “goo” in FW & other silt sample in SW.

Possible follow up: 1. Continue exploring the end of “Shells” W/NW.

Comments/observation:

Line name: Shells Passage width (meters): 5-30 Passage Height (meters): 2-10 Passage Shape: Canyon, Dome Fauna: Shrimp Speleothems: Orange, Stalactities, Stalagmites, Fossils

102 Sediment: Grey, Orange, organic, clay, ripples, flat, percolation Infill: Breakdown Water: Halocline near floor, halocline near ceiling Additional Comments: Finally spotted lots of fossilized shells at around 8,000 feet. There’s no doubt that the end of “Shells” can reveal more awesome salt-water passageways.

Comments/observation:

Line name: Orange Farm Passage width (meters): 12 Passage Height (meters): 2 Passage Shape: Bedding plane Fauna: Shrimp Speleothems: Orange, stalactites, stalagmites, flowstone Sediment: Grey, organic, clay, flat percolation Infill: Swiss Cheese Water: Halocline mid passage, milky water Additional Comments:

Comments/observation:

Line name: Dreadlock Passage width (meters): 12 Passage Height (meters): 2 Passage Shape: Vertical fracture, Bedding plane Fauna: Shrimp Speleothems: Orange, stalactites, stalagmites, flowstone Sediment: Grey, organic, clay, flat percolation Infill: Swiss Cheese Water: Halocline mid passage, milky water Additional Comments:

Equipment and Survey: 4 stages and 2 scooters per diver (2 x 33amp). It took 35 minutes to scooter to first T. Per “4” scooter is slow. Survey was done on the way in. Survey can be challenging due to lack of viz.

103

Dive log:

Dive # 19 Dive # 20

Time in: 11h30 Time in: 12h30 Time out : 15h10 Time out: 14h00 Total run time: 220 minutes Total run time: 90 minutes Max Depth: 73feet Max Depth: 55 feet Av Depth: 60 feet Av Depth: 45 feet Total exploration: 1,204 feet Total exploration: 337 feet Divers: Per & Chris Divers: Fred & Alex Line Names: “Shells” Line Names: “Dread Lock”, “Orange Farm”

104 105 106

Line Name Shells Date Explored 6-Apr-06 Explored By Chris and Per Surveyed By Chris Tie in Station CMFZZ20 Compass CMFSH prefix

MAX Depth in Feet 73 MIN Depth in Feet 24 Total Dist in Feet 1204

MAX Depth in Meters 22.12 MIN Depth in Meters 7.27 Total Dist in Meters 364.85

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 57 25 165 START,>SK#41,WflowE 1 2 2 58 36 233 WflowE 2 3 3 59 23 153 WflowE 3 4 4 48 25 239 >SK#49,!SE!? THROUGH BREAKDOWN 4 5 5 40 24 220 BREAKDOWN AREA 5 6 6 34 34 214 BREAKDOWN AREA 6 7 7 24 25 208 BREAKDOWN AREA 7 8 8 28 69 281 BREAKDOWN AREA,>SK#50,!SSE!? THROUGH BREAKDOWN 8 9 9 55 15 258 B 9 10 10 57 54 196 10 11 11 63 20 206 11 12 12 61 32 210 >SK#52,!SE! 12 13 13 60 24 247 13 14 14 54 33 260 SWbigflowNE 14 15 15 53 81 264 SWbigflowNE,DEFINED TUNNEL 15 16 16 61 30 260 STAGE DROP#3 16 17 17 61 87 264 17 18 18 63 49 340 18 19 19 61 20 46 19 20 20 61 18 308 20 21 21 62 42 252 21 22 22 60 36 268 22 23 23 59 20 270 23 24 24 59 67 316 24 25 25 63 32 319 H ON CEILING,FLOW RIPPLES 25 26 26 65 51 258 H ON CEILING,FLOW RIPPLES 26 27 27 68 76 308 H ON CEILING,FLOW RIPPLES

107 27 28 28 73 50 264 H ON CEILING,FLOW RIPPLES 28 29 29 69 26 254 H ON CEILING,FLOW RIPPLES 29 30 30 70 42 284 H ON CEILING,FLOW RIPPLES 30 31 31 71 38 280 H ON CEILING,FLOW RIPPLES 31 32 32 64 >SK#51,!NW!,!SW! BIG DOME 32 33 33

Line Name Dreadlock Date Explored 6-Apr-06 Explored By Alex, Fred Surveyed By Alex Tie in Station CMFFN12 Compass CMFDL prefix

MAX Depth in Feet 48 MIN Depth in Feet 31 Total Dist in Feet 135

MAX Depth in Meters 14 MIN Depth in Meters 9 Total Dist in Meters 41

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 31 40 345 START,>SK#15 1 2 2 39 25 40 SED.SAMPLE 3(LOST) 2 3 3 47 45 320 3 4 4 47 25 330 4 5 5 48 END,>SK#34,SED.SAMPLE 1+2 5 6 6

108 Line Name Orange Farm Date Explored 6-Apr-06 Explored By Fred, Alex Surveyed By Alex Tie in Station CMFFN17 Compass CMFOF prefix

MAX Depth in Feet 47 MIN Depth in Feet 44 Total Dist in Feet 202

MAX Depth in Meters 14.35 MIN Depth in Meters 13.26 Total Dist in Meters 61.21

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 47 45 130 START,>SK#14 1 2 2 47 29 108 2 3 3 45 31 70 NflowSE,!SE! 3 4 4 44 46 0 4 5 5 44 32 100 5 6 6 44 19 58 6 7 7 44 END,>SK#40,!N! 7 8 8

109

110

Diving Operations April 7th, 2006

Dive Team: Alex Alvarez, Fred Devos, Chris Le Maillot, Per Thomsen

Surface Support: Esteban

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: The wind direction has changed to East. Lagoon water is now murky. There was a strong flow at the entrance of cave. Flow at the entrance seems stronger during afternoon dive.

Objectives: 1. Extend the exploration at 5K to the SW following leads off of the “Gandalf” line.

Summary of results: 1. Additional 1,400ft added from a lead off of the “Gandalf” Line. The new line is called “Artery”. The new cave is impressive size-wise. This line was laid head-on to the flow going pretty much strait SW. Also, there’s SE/W/NW lead. The cave has some nicely carved canyons. The ceiling is at 40ft and the bottom of the cave is in excess of 80ft. The end of the line is needless to say wide-open for more SW/W exploration

Possible follow up: 1. Continue exploring the end of the SW line at 6,500 feet.

Comments/observation:

Line name: Artery Passage width (meters): 5 Passage Height (meters): 6 Passage Shape: Canyon, Dome, Phreatic tube Fauna: Shrimp Speleothems: White, orange, stalagtite Sediment: Orange, white, organic, clay, flat, percolation Infill: Breakdown Water: Halocline mid passage, halocline near ceiling Additional Comments: The cave passage 6,000 feet in is similar in size to what is encountered in OBH & Yax Chen upstream.

111

Equipment and Survey: 4 stages and 2 scooters per diver (2 x 33amp). It took 35 minutes to scooter to first T. Per “4” scooter is slow. Survey was done on the way in. This is a better method of survey as there’s plenty of gas for exit and no unnecessary time pressure. Also, this is a better way to document cave. Survey can be challenging due to lack of visibility.

Dive log:

Dive # 21

Time in: 11h00 Time out : 14h25 Total run time: 205 minutes Max Depth: 70feet Av Depth: 60 feet Total exploration: 1,400 feet Divers: Fred& Per Line Names: “Artery”

112 113

Line Name Artery Date Explored 7-Apr-06 Explored By Fred, Per Surveyed By Fred Tie in Station CMFG18 Compass CMFAL prefix

MAX Depth in Feet 67 MIN Depth in Feet 37 Total Dist in Feet 1328

MAX Depth in Meters 20.30 MIN Depth in Meters 11.21 Total Dist in Meters 402.42 FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 47 27 16 >SK2006#19,START 1 2 2 43 76 356 !N! 2 3 3 55 75 236 3 4 4 53 43 190 4 5 5 55 25 217 5 6 6 53 32 240 6 7 7 44 75 207 7 8 8 44 33 227 8 9 9 37 39 227 9 10 10 58 56 227 10 11 11 56 41 226 SflowN,CANYON 11 12 12 56 126 234 !SE!!NW!,>SK0406#48 12 13 13 59 58 237 >SK0406#47,!S!,!W!,!N!?,SflowN 13 14 14 49 90 240 SK0406#46,!S! 14 15 15 48 24 264 15 16 16 51 71 262 BROKEN STALAGTITE 16 17 17 42 143 208 !NW! DEEP 17 18 18 52 49 170 >SK0604#40?,!SW!,SWflowNE,ST AGE DROP 18 19 19 60 18 180 !E! 19 20 20 59 72 237 20 21 21 54 47 242 !SE! 21 22 22 60 45 190 SWflowNE,H (SHALLOWER THAN NORMAL) 22 23 23 53 26 227 23 24 24 67 37 214 24 25 25 62 END,>SKO406#39,!SW!,SWflowNE

114

115 Diving Operations April 8th, 2006

Dive Team: Alex Alvarez, Fred Devos, Chris Le Maillot, Per Thomsen

Surface Support: Esteban

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinate: UTM (WGS84): 16 Q 449018 2220411

Conditions: The wind direction has changed to East. Lagoon water is now murky. There was almost no flow at the entrance of cave. Remoras are back.

Objectives: 1. Extend the exploration at 6 ½ K to the SW/W 2. Scout possible lead at around 3K 3. Retrieve safeties at 4K

Summary of results: 1. Additional 1,400ft added to the W/SW. New line name is “Paso del Sur”. The end of the line is now at 8,200ft from entrance. The cave is impressive size- wise. The W/NW heading usually leads to shallower (45ft) big & decorated domes. There is always a SW passage coming off domes. There’s a tendency to head W/NW in big decorated dome but staying at 60ft near halocline due SW is perhaps better for exploration. The cave is BIG. There a well define tunnel with substantial flow following big crack on the ceiling. The end of line is open to the SW with good flow. 2. Successful scouting & observation on the first part of cave. 3K in there’s a mangrove ceiling that need to be further explored. This could have been a massive opening in the past. There’s on-going cave to the SE. This looks like a siphon. 3. Retrieved safeties OK

Possible follow up: 1. Continue exploring the end of the “Paso del Sur” line at 8,200 ft. 2. Explore & document cave within 30 minutes from entrance

Comments/observation:

Line name: Paso del Sur Passage width (meters): 12 Passage Height (meters): 4 Passage Shape: Vertical fracture, Canyon, Dome

116 Fauna: Shrimp, remoras in entrance Speleothems: White, stalactite, stalagmite, flowstone Sediment: Orange, organic, ripples, percolation Infill: Breakdown Water: Halocline mid passage, halocline near ceiling Additional Comments: 1. The cave is massive further inland. More exploration near the entrance is needed to better understand water movements. 2. There will be a need for more safeties at 7K for next project. The lack of cenotes, depth, silt and flow requires more bailout gas. This is a necessity for push team. 3. Possible switch from EAN’x 32 to 30/30 for next project.

Equipment and Survey: 3 stages and 2 scooters per diver (2 x 33amp). It took 35 minutes to scooter to first T. Per “4” scooter is slow. Survey was done on the way in.

Dive log:

Dive # 22 Dive # 23

Time in: 10h30 Time in: 11h00 Time out : 13h45 Time out: 1h30 Total run time: 195 minutes Total run time: 150 minutes Max Depth: 68feet Max Depth: 55 feet Av Depth: 60 feet Av Depth: 45 feet Total exploration: 1,400 feet Total exploration: Divers: Fred& Chris Divers: Per & Alex Line Names: “Paso del Sur” Line Names:

117 118

Line Name Paso del Sur Date Explored 8-Apr-06 Explored By Fred and Chris Surveyed By Fred Tie in Station CMFAL24 Compass CMFPS1 prefix MAX Depth in Feet 68 MIN Depth in Feet 34 Total Dist in Feet 1465 MAX Depth in Meters 20.61 MIN Depth in Meters 10.30 Total Dist in Meters 443.94

FROM TO Station Depth DIST Azimut COMMENTS # (Feet) (Feet) h IN 0 0 1 1 63 46 238 START,>SK#39,H 1 2 2 61 22 208 >SK#38,!WNW! 2 3 3 58 16 240 3 4 4 49 76 248 4 5 5 40 82 198 5 6 6 34 17 247 6 7 7 34 35 308 7 8 8 35 20 358 8 9 9 53 30 276 9 10 10 50 28 316 10 11 11 48 77 287 11 12 12 48 37 239 STAGE DROP 12 13 13 51 49 244 SWflowNE,DEEP FLOOR 13 14 14 49 28 264 14 15 15 46 35 296 15 16 16 42 66 314 16 17 17 38 53 260 17 18 18 48 73 277 18 19 19 54 34 268 SWflowNE 19 20 20 57 46 234 20 21 21 57 21 236 21 22 22 54 67 258 22 23 23 54 63 242 SWflowNE 23 24 24 57 45 252 24 25 25 65 65 264 25 26 26 66 48 242 v^v^v 26 27 27 68 60 246 27 28 28 59 80 263 28 29 29 60 54 178 29 30 30 66 92 258 30 31 31 63 END,

119

120

May 2006

121 Surface Exploration May 9th, 2006

Team: Sam Meacham, Mario Rebolledo-Vieyra, Robert Schmittner, Jack Sherman

Equipment used: TDSWay RECON GPS, Midland Radios, Suunto M3 compass, topographical maps, hard copy of aerial photographs, Nokia cel phone, Olympus 4040C camera

Area of work: Northern Sian Ka’an Boundary Limit (see map)

Objectives: • To investigate two open water areas to the south of the Chunyaxche Boca Paila Canal • Investigate raised area of vegetation known as Cayo Venado • Observe wildlife

Access: Access was by boat from Muyil then on foot. We followed overgrown canals all the way down. We were able to go in the canals at first but had to get out and follow along side them most of the way due to dense vegetation. The savanna areas had deep mud and water channels that had to be negotiated. RECON made navigation easy.

Summary of results: We were able to locate the two open water areas. The first, target one, is fed on the north and south side by a small canal. This may explain the presence of the school of juvenile tarpon we found swimming in the pool. Maximum depth was around 2 meters. Although it looked promising from the surface, there was no cave to be found. The second target area turned out to be a dense area of red mangrove with standing water around its edges, also fed by small a canal. Crossing the savanna to Cayo Venado was difficult at times due to dense ‘bog’ like areas. Once reaching Cayo Venado the vegetation changes dramatically due to the exposed rock that makes up the Cayo. The orientation of Cayo Venado points directly northeast to the tip of the main canal then on to the ‘Gem’ Cenotes. Is this a coincidence? There may be something going on here. The borders of the Cayo are surrounded by saw grass, red mangrove and Xiit palm. It was difficult going made even more so by the heat of the day.

Wildlife observed: • Tarpon

Possible Followup: Would be interesting to spend more time in this area. Heading south there are more canals and what seem to be open water area.

122

Overview of area of surface exploration May 9th, 2006

123

Detail of surface exploration May 9th, 2006, photos markers correspond to the photos on the following page

124

Target 1, tarpon were observed here, but no cave Robbie navigates a small canal on way to target 1

Target turns out to be an area of dense mangrove Jack in the middle of the savanna

Looking west from Cayo Venado Robbie cools off in the main canal after a long hot day

125

Surface Exploration May 17th-18th, 2006

Team: Sam Meacham, Pepe Sanchez

Equipment used: TDSWay RECON GPS, Midland Radios, Suunto M3 compass, topographical maps, hard copy of aerial photographs, Nokia cel phone, Olympus 4040C camera

Area of work: Northern Sian Ka’an Boundary Limit (see map)

Objectives: • To investigate an anomaly observed on the aerial photographs that may be an archeological site. • Investigate a canal heading from Laguna Caapechen inland. • Investigate bluff point at the far west end of Laguna Caapechen • Observe wildlife Access: Access was by kayak and foot. We camped two nights in two separate locations in order to maximize our time in the field. Once again the RECON made navigation easy.

Summary of results: Upon closer investigation, the anomaly we thought to be archeological in nature turned out to be a hummock instead. Although we got close to the canal we wanted to investigate, we were unable to continue due to time constraints. We found and marked a new ‘ojo de agua’. Although it seems to small for a diver to enter, there is strong flow of water discharging from it suggesting that cave passage may lie below. An abundance of wildlife was observed. We are able to locate the bluff area seen on the aerial photographs. Of interest was the beach we landed on which was comprised of sand rather than the normal mud banks we have come across.

Wildlife observed: • Nesting herons • Two crocodile nests • Stingrays in canal • Baby crocodiles heard • Tracks of a large animal were observed next to camp #2 • Deer or javali tracks observed • Large variety of shore birds (herons, spoonbills, Osprey, cormorants)

Possible Followup: Still need to go back and investigate the canal way.

126

Overview of area of surface exploration May 17th–18th , 2006

127

Detail of surface exploration May 17th-18th, 2006, photos markers correspond to the photos on the following page

128

camp #1 'Archeological Site' that turned out to be a hummock

camp #2 Freshly made crocodile nest

Newly discovered 'Ojo de Agua' 'Sand' beach

View towards coast from elevation high point on bluff

129 Diving Operations May 16th, 2006

Dive Team: Franco Attolini,, Daniel Riordan, Fred Devos & Chris Le Maillot.

Surface support: Mario Valotta

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: North wind, water in the Laguna calm, strong flow at the entrance of the cave. Manatees were seen all day long (at least 3).

Dive Objectives: 1. Drop safeties at 4k & 7k 2. Photo shoot in the first part of the cave

Summary of results: 1. Dropped safeties OK. It took 35 minutes to scooter to first safety drop point & 55 minutes to second drop. 2. Photo shoot with Danny to Key Hole

Possible follow up: 1. We have a need for more photo & video. We can spend more time during the next project for photos.

Comments/observation:

Line name: Passage width (meters): Passage Height (meters): Passage Shape: Fauna: Manatees in entrance Speleothems: Sediment: Infill: Water: Additional Comments: 1. The team was a lot more effective in dropping the safeties. 30/30 in the stages made the difference. 2. Lots of shrimp observed during photo shoot. 3. Cave system is named Caapechen.

130

Equipment and Survey: 4 stages (2 x safeties) & 2 scooters per diver (2 x 33amp).

Dive log:

Dive # 24 Dive # 25

Time in: 11h42 Time in: 14h35 Time out : 14h02 Time out: 15h40 Total run time: 145 minutes Total run time: 95 minutes Max Depth: 69feet Max Depth: 54 feet Av Depth: 50 feet Av Depth: 45 feet Total exploration: Total exploration: Divers: Fred & Chris Divers: Fred, Danny & Chris

131 Diving Operations May 17th, 2006

Dive Team: Fred Devos & Chris Le Maillot

Surface Support: Franco Attolini, Mario Valotta

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: North wind, water in the Laguna calm, strong flow at the entrance of the cave. Manatees were seen in the am.

Dive Objectives: 1. Explore the end of “Paso del Sur” line at 8,213ft 2. Explore the various marked lead closer to the entrance

Summary of results: 1. Added another 1,100ft of line (Madre) going SW. The cave was in a bedding plane. Followed the flow to a big decorated room. Tried to keep a SW heading past the decorated room but cave stop in a dome rich in fragile speleothems. End of line is now at 9,366ft. 2. Checked several leads closer to the entrance but no luck.

Possible follow up: 1. There’s an N/NW lead to check towards the end of the line “Madre” past bedding plane.

Comments/observation:

Line name: Madre Passage width (meters): 2-10 Passage Height (meters): 2-6 Passage Shape: Bedding plane, Dome Fauna: Shrimp Speleothems: Brown, stalactite, stalagmite, flowstone, fossils, calcite rafts Sediment: Brown, white, Organic, clay, flat, percolation Infill: Swiss cheese, breakdown Water: Halocline near floor, halocline mid passage Additional Comments: 1. Cave was finely decorated. 2. The cave may be changing direction? There’s a good N/NW lead to be checked. This will

132 require a set-up dive.

Equipment and Survey: 4 stages and 2 scooters per diver (2 x 33amp).

Dive log:

Dive # 26 Dive # 27

Time in: 11h30 Time in: 16h05 Time out : 15h40 Time out: 17h35 Total run time: 250 minutes Total run time: 90 minutes Max Depth: 71feet Max Depth: 61 feet Av Depth: 60 feet Av Depth: 45 feet Total Exploration: 1,100 feet Total exploration: Divers: Fred & Chris Divers: Fred, Chris, Franco Line Names: Madre

133 134 Line Name Madre Date Explored 17-May-06 Explored By Fred and Chris Surveyed By Fred Tie in Station CMFPS30 Compass CMFMAD prefix

MAX Depth in Feet 71 MIN Depth in Feet 55 Total Dist in Feet 1153 MAX Depth in Meters 21.52 MIN Depth in Meters 16.67 Total Dist in Meters 349.39

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 64 10 303 START,>SK04-06#53 1 2 2 62 44 162 2 3 3 65 30 224 3 4 4 65 66 214 4 5 5 71 68 279 5 6 6 66 58 256 6 7 7 64 50 229 7 8 8 65 39 181 8 9 9 65 50 248 ON FLOOR 9 10 10 67 29 302 10 11 11 66 57 334 11 12 12 64 57 247 !N! 12 13 13 63 31 284 13 14 14 65 30 224 14 15 15 65 26 235 STAGE 3DROP 15 16 16 65 19 256 LOW CEILING START 16 17 17 64 22 281 17 18 18 65 39 16 H=65FT 18 19 19 65 30 299 H=66FT 19 20 20 68 23 273 20 21 21 67 34 230 21 22 22 66 42 276 Sflow? 22 23 23 64 20 232 LOW CEILING END 23 24 24 57 88 232 BIG ROOM 24 25 25 55 67 139 25 26 26 69 62 206 26 27 27 67 42 214 27 28 28 61 20 129 28 29 29 62

135

136 Diving Operations May 18th, 2006

Dive Team: Fred Devos & Chris Le Maillot

Surface Support: Franco Attolini, Mario Valotta, Roberto Chavez

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinate: UTM (WGS84) 16 Q 449018 2220411

Conditions: North wind, water in the Laguna calm, strong flow at the entrance of the cave. Manatees were seen & photographed by Roberto.

Dive Objectives: 1. Check out leads from “Paso Del Sur” going back towards 1st T 2. Explore lead near the mangrove ceiling

Summary of results: 1. Added 571ft of line (Hook) going NE then S from “Paso del Sur”. The beginning of the passage is simply the other side of a big canyon. This is a deeper salt water area with a maximum depth of 71ft. The end of the line is restricted with no viz. 2. Checked out previously marked leads (# SM102, # SM46, # SM38, # SM18, # SM5, #SM6) without success. Frustrating dive for what looked to be promising ended up not going anywhere. Percolation is bad in new areas. 3. Added 477ft of line (Mangrove) going around the mangrove ceiling area. The ceiling is at a depth of 35ft. The lead looped back to main line. Viz was extremely poor. There’s little doubt that this was a cenote in the past.

Possible follow up: There’s a lot more area off main line to check out for side tunnel especially in salt-water lens.

Comments/observation:

Line name: Hook Passage width (meters): 2 Passage Height (meters): 3 Passage Shape: Canyon, Dome Fauna: Manatees in entrance (photos taken) Speleothems: Brown, flowstone, fossils Sediment: Brown, organic clay, flat, percolation Infill: Swiss Cheese, breakdown Water: Halocline mid passage, halocline near ceiling

137 Additional Comments: 1. Halocline seems to be slightly shallower near the entrance. Viz was poor in salt water.

Comments/observation:

Line name: Mangrove Passage width (meters): 4 Passage Height (meters): 3 Passage Shape: D Fauna: Shrimp Speleothems: Sediment: Red, organic, clay, flat, percolation Infill: Breakdown Water: Freshwater only Additional Comments:

Equipment and Survey: 4 stages and 2 scooters per diver (2 x 33amp).

Dive log:

Dive # 28 Dive # 29

Time in: 11h00 Time in: 16h13 Time out : 15h45 Time out: 17h43 Total run time: 280 minutes Total run time: 87 minutes Max Depth: 70 feet Max Depth: 65 feet Av Depth: 60 feet Av Depth: 50 feet Total exploration: 571 feet Total exploration: 477 feet Divers: Fred & Chris Divers: Alex, Fred & Chris Line Name: “Hook” Line Names: “Mangrove”

138 139 140

Line Name Hook Line Date Explored 18-May-06 Explored By Fred and Chris Surveyed By Fred Tie in Station CMFPS1 Compass CMFHL prefix

MAX Depth in Feet 70 MIN Depth in Feet 60 Total Dist in Feet 571

MAX Depth in Meters 21.21 MIN Depth in Meters 18.18 Total Dist in Meters 173.03

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 60 32 204 START,>SK04- 06#38 1 2 2 61 39 99 T 2 3 3 62 52 82 3 4 4 64 34 113 4 5 5 60 42 40 SWflowNE 5 6 6 62 73 344 6 7 7 65 69 67 7 8 8 69 37 89 !N! (to Artery?) 8 9 9 66 44 134 9 10 10 66 36 42 10 11 11 70 18 31 11 12 12 64 21 112 12 13 13 64 18 138 13 14 14 62 26 154 14 15 15 68 30 195 15 16 16 67 END,>05-2000 #102

141 Line Name Mangrove Line Date Explored 18-May-06 Explored By Alex, Fred, Chris Surveyed By Fred Tie in Station CMFFF20 Compass CMFMAN prefix

MAX Depth in Feet 43 MIN Depth in Feet 23 Total Dist in Feet 477

MAX Depth in Meters 13.03 MIN Depth in Meters 6.97 Total Dist in Meters 144.55

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 31 36 249 Jump Station? 1 2 2 43 56 217 M.L.,>SK05-2006 #104,>? 2 3 3 40 26 100 JUMP 3 4 4 29 135 91 START 4 5 5 24 55 121 5 6 6 32 22 340 6 7 7 30 31 356 7 8 8 33 38 24 8 9 9 33 78 0 >108 9 10 10 23 JUMP,M.L.,>107,>106

142

143 Diving Operations May 19th, 2006

Dive Team: Fred Devos & Chris Le Maillot

Surface Support: Franco Attolini, Mario Valotta, Roberto Chavez

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinate: UTM (WGS84) 16 Q 449018 2220411

Conditions: North wind, water in the Laguna calm, strong flow at the entrance of the cave. Manatee observed in the pm.

Dive Objectives: 1. Check out leads from “Silica Dome” line going SW. 2. Probe north line near entrance & photo document different sediment.

Summary of results: 1. Added 1,159ft of line (Fracture South) going SW from “Silica Dome”. This is a very interesting part of the cave. There’s a fracture tunnel running N-S w/speleothems at an average depth of 65ft. The end of the line is wide open back in the halocline w/flow noticeable. Viz is challenging. The line runs between the 2 previously laid SW line. 2. Photos taken of different sediment. 3. Re-surveyed ML near mangroves.

Possible follow up: The end of the line “Fracture South” is in need of further investigation. This is still T’ed in “Silica Dome” line.

Comments/observation:

Line name: Fracture South Passage width (meters): 4 Passage Height (meters): 3 Passage Shape: Canyon Fauna: Shrimp, manatees and permits in entrance Speleothems: Orange, stalactites, stalagmites Sediment: Orange, clay, percolation Infill: Swiss Cheese, Breakdown Water: Halocline near ceiling Additional Comments: 1. Halocline seems to be slightly shallower near the entrance. Viz was still poor in salt water.

144 2. Large school of juvenile permit. 3. Left in the cave 2-safety bottles w/EANx 32 at 4K.

Equipment and Survey: 4 stages and 2 scooters per diver (2 x 33amp).

Dive log:

Dive # 30 Dive # 31

Time in: 11h37 Time in: 16h13 Time out : 15h15 Time out: 17h43 Total run time: 220 minutes Total run time: 87 minutes Max Depth: 71 feet Max Depth: 65 feet Av Depth: 62 feet Av Depth: 50 feet Total exploration: 1,159 feet Total exploration: Divers: Fred & Chris Divers: Fred & Chris, Roberto Line Names: Fracture South Line Names:

145 146

Line Name Fracture South Date Explored 19-May-06 Explored By Fred and Chris Surveyed By Fred Tie in Station CMFSD25 Compass CMFFRAC prefix

MAX Depth in Feet 71 MIN Depth in Feet 58 Total Dist in Feet 1159

MAX Depth in Meters 21.52 MIN Depth in Meters 17.58 Total Dist in Meters 351.21

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 60 8 231 1 2 2 60 35 161 START,T,>SK111 2 3 3 63 27 195 R 3 4 4 59 11 178 4 5 5 59 10 178 5 6 6 61 23 294 6 7 7 61 20 276 7 8 8 65 12 224 8 9 9 66 34 195 9 10 10 66 72 211 10 11 11 65 30 148 11 12 12 66 62 193 !W! 12 13 13 62 24 160 13 14 14 68 23 316 14 15 15 58 34 229 15 16 16 59 34 188 16 17 17 67 12 267 17 18 18 67 33 188 18 19 19 63 58 208 19 20 20 66 33 249 20 21 21 66 9 13 21 22 22 70 23 323 R-DUCK UNDER 22 23 23 65 37 264 23 24 24 66 32 290 24 25 25 67 10 210 25 26 26 66 33 262

147 26 27 27 64 13 200 27 28 28 65 29 184 28 29 29 66 20 238 29 30 30 68 40 186 30 31 31 67 27 250 31 32 32 65 30 192 32 33 33 62 25 224 33 34 34 63 17 251 34 35 35 71 20 204 35 36 36 66 25 159 36 37 37 60 16 195 37 38 38 59 32 268 SWflowNE 38 39 39 62 83 271 39 40 40 60 43 206 40 41 41 61 END,H,>SK05- 2006#112,SWflowNE,!240!

148

149

Diving Operations May 20th, 2006

Dive Team: Franco Attolini,, Fred Devos, Chris Le Maillot

Surface Support: Mario Valotta

Dive site #1 Name: Entrada Oxpechen #1 Coordinate: UTM (WGS84): 16 Q 448288 2221179

Conditions: Water conditions are generally good in this cave although flow dissipates almost immediately upon penetration where percolation begins. The "downstream" portion has rolling hills of sediment and quickly becomes restricted with very poor visibility.

Dive site #2 Name: Entrada Oxpechen #2 Coordinate: UTM (WGS84): 16 Q 0448831 2221179

Conditions: The lack of flow create poorer water conditions than the other caves and fine sediment is easily disturbed. Entering the cave requires pushing away the floor sediment.

Dive Objectives: 1. Check out Oxpechen openings # 1 and #2 2. Complete trip report & sort out survey data & mapping.

Summary of results: 1. Explored and surveyed new cave in Oxpechen #2. Line name “Snow” for a total of 431ft going N. V slight flow at the entrance. From the opening at 20ft the cave slopes down to 65ft. Slight halocline at 63ft. Opening is challenging with hydrogen sulfide & hills of organic silt covering clay bed. 2. Oxpechen # 1 checked out again (already dove during Feb 2006 project). Pushed SE side of the opening that was heavily clogged with white organic sediment.

Possible follow up: The end of the line “Fracture South” is in need of further investigation. This is still T’ed in “Silica Dome” line.

Comments/observation:

Line name: Snow Passage width (meters): 10

150 Passage Height (meters): 4 Passage Shape: Bedding Plane, Flat ceiling Fauna: Lots of shrimp Speleothems: White, stalactites, stalagmites, flowstone Sediment: White, organic, percolation Infill: Swiss Cheese Water: Halocline near floor Additional Comments:

Equipment and Survey: 1 stage and Backgas (Double tanks) only per diver.

Dive log:

Dive # 32 Dive # 33

Time in: 11h00 Time in: 12h45 Time out : 12h20 Time out: 13h45 Total run time: 40 minutes Total run time: 60 minutes Max Depth: 44feet Max Depth: 68 feet Av Depth: 35 feet Av Depth: 55 feet Total exploration: Total exploration: 431 feet Divers: Fred & Franco Divers: Fred & Franco Line Names: “Snow”

Dive # 34

Time in: 14h30 Time out : 15h18 Total run time: 48 minutes Max Depth: 58feet Av Depth: 38 feet Divers: Fred & Mario

151 152 Line Name Snow Date Explored 20-May-06 Explored By Fred and Franco Surveyed By Fred Tie in Station Line begins Compass SKOXTS SKOXTS0 prefix

MAX Depth in Feet 64 MIN Depth in Feet 20 Total Dist in Feet 431

MAX Depth in Meters 19.39 MIN Depth in Meters 6.06 Total Dist in Meters 130.61

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 20 15 98 START,OPEN WATER 1 2 2 26 33 209 NEflowSW 2 3 3 35 50 196 CEILING 3 4 4 38 51 140 CEILING 4 5 5 44 35 165 CEILING 5 6 6 48 25 132 6 7 7 51 31 157 7 8 8 59 38 189 !W! 8 9 9 61 15 203 STAG 9 10 10 61 33 243 10 11 11 62 26 208 11 12 12 63 45 231 12 13 13 64 34 121 !NE! 13 14 14 63 END,!NE!,^v^v

153

154

June 2006

155 Diving Operations June 13th, 2006

Dive Team: Fred Devos, Daniel Riordan, Per Thomsen

Surface support: Nathan Campbell & Johanna Rodriguez.

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinate: UTM (WGS84): 16 Q 449018 2220411

Conditions: The wind was blowing from the North, then at the end of the day from the SE. This seems to be once again relevant to the water conditions at the entrance of the cave. The surface of the Laguna was calm. There was a good flow going in for the dive but no flow going out of the cave 240 minutes later. As a result, the visibility for the last few hundred feet leading to the exit was bad (2ft). No daylight was visible from the end of the line. There’s a need for more safeties at 1000ft. There’s a possibility that the water could reverse in the cave? The water temp at the entrance of the cave was 86F! Where is the water from further upstream going to if not out through the entrance?

Dive Objectives: 1. Check on safeties that were left in the cave at 4K from last project 2. Add 2 other safeties at 7K for continuing exploration at the end of “Shells”

3. Cut T to “Fracture South” back 4. Photograph section of cave from 4K to 7K.

Summary of results: 1. Safety at 4K needed to be worked on. Regulator was full of silt and in need of adjustment. 2. Safeties dropped OK at 7K 3. Cut T ok under heavy silt. This is a particularly challenging part of the cave with silt, halocline and narrow passageway. 4. Photographed area of cave from 4K to “Silica Dome” & “Gandalf” area. Heavy percolation has made photo shoot challenging.

Possible follow up: 1. Extend the exploration of the end of “Shells” line. 2. More documentation of the cave further in.

156

Equipment and Survey: 3 stages and 2 scooters per diver (2 x 33amp). Per # 4 is slow. Per # 1 & # 6 need more weight.

Dive log:

Dive # 35

Time in: 13h15 Time out : 17h44 Total run time: 269 minutes Max Depth: 69feet Av Depth: 62 feet Divers: Fred, Danny, Per

157

Diving Operations June 14th, 2006

Dive Team: Daniel Riordan, Per Thomsen , Fred Devos

Surface support: Fred Devos

Dive site Name: Entrada Boca Paila Coordinates: UTM (WGS 84): 16 Q 448606 2212441

Conditions: Entrada Boca Paila is a very promising entrance for further exploration. Water conditions are clear. There is substantial flow at the entrance which dissipates as one proceeds further back. Halocline is at 48 feet. Mangrove roots penetrate down into the cave. The observation ctenophores within the cave is exciting and may be evidence of a relationship between the cave and the Caribbean Sea directly to the east.

Dive Objectives: 1. Enter cave entrance in Boca Paila & re-survey existing French line. 2. Further exploration in the upstream section 3. Check out siphon side

Summary of results: 1. Re-surveyed and replaced of 371ft of existing French line ok. 2. Explored and surveyed another 1,025ft of line. Line name: “Half Moon” going upstream W/SW big. There are a lot of leads going off main tunnel. The tunnel is big with flow. It seems that there is more water movement than Caapechen. More defined cave. Less organic silt in the first 400ft of cave. 3. Siphon side is small 2x2. There’s French line going into smaller cave. There’s a large half moon shape opening a lot further downstream visible from the boat.

Possible follow up: 1. Continue the exploration both upstream & downstream

Comments/observation:

Line name: Half Moon Passage width (meters): 10 Passage Height (meters): 5 Passage Shape: Canyon Fauna: Shrimp, Jellyfish Speleothems: Gray, Brown, Stalactites, stalagmites Sediment: Grey, Organic, Flat, Percolation

158 Infill: Water: Halocline varies from floor to ceiling Additional Comments: 1. Chris sprained right ankle carrying equipment to the boat. We have postponed plan to push the end of “Shells” to June 15. 2. The right hand wall of the upstream Boca Paila cave is a compact wall of mangrove roots & dirt. 3. A few small jellyfish (Ctenophores) were observed slightly below the halocline 1,200ft in. 4. Flow is substantial and blowing out through entry hole which is located in the ceiling of the cave. 5. Halocline at 48ft.

Equipment and Survey: 2 stages and 1 scooters per diver (1 x 33amp)., survey in.

Dive log:

Dive # 37

Time in: 13h15 Time out : 15h25 Total run time: 140 minutes Max Depth: 60feet Av Depth: 43 feet Total Exploration: 1,396 feet Divers: Fred, Danny, Per Line Names: “Half Moon”

159 160

Line Name Half Moon Date Explored 14-Jun-06 Explored By Fred, Danny, Per Surveyed By Fred Tie in Station Line begins here

MAX Depth in Feet 54 MIN Depth in Feet 24 Total Dist in Feet 1396

MAX Depth in Meters 16.36 MIN Depth in Meters 7.27 Total Dist in Meters 423.03

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 25 9 181 START,!NE! 1 2 2 25 22 234 2 3 3 24 23 210 3 4 4 38 22 205 4 5 5 33 37 215 5 6 6 33 31 216 6 7 7 34 56 200 7 8 8 39 52 181 8 9 9 31 71 210 >SK 33,!NW! 9 10 10 28 48 198 ROOTS 10 11 11 34 35 299 ROOTS,SK 32,!SW!,FRENCH LINE 11 12 12 28 52 276 ROOTS 12 13 13 28 87 230 STAGE 1 DROP 13 14 14 44 73 254 >SK31,!NE! 14 15 15 36 76 286 MILKY WATER STARTS 15 16 16 44 78 295 16 17 17 40 43 258 17 18 18 46 72 276 !SW! 18 19 19 48 69 275 H 19 20 20 50 44 262 20 21 21 52 63 239 21 22 22 42 108 215 22 23 23 47 46 253 HAIR ON SEDIMENT 23 24 24 52 45 313 CTENOPHORES,STAGE 2 DROP 24 25 25 54 17 285 25 26 26 49 40 5 26 27 27 48 49 270 WflowE 27 28 28 48 28 198 !NW! 28 29 29 50 !SW!,END

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162 Diving Operations June 15th, 2006

Dive Team: Fred Devos, Daniel Riordan, Per Thomsen

Surface support: Sam Meacham, Roberto Chavez.

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: N/A

Dive Objectives: 1. Explore the end of line “Shells” 2. Carry hydrolab in as far upstream as possible for measurements. This is in collaboration with Centro de Estudios de Agua.

Summary of results: 1. Explored & surveyed 1,539ft (line name: Hydro) of cave at the end of Shells. This is a big and more define tunnel going SW/W. The flow is substantial. End of the line is wide open. Max penetration from the entrance Manatee is: 9,681ft. 2. Hydro-lab was brought to the end of line to measure general profile of water column.

Possible follow up: 1. Continue the exploration of the end of the line. This seems to be a very promising area of cave. Future exploration there will likely require set-up dives. 2. More science dives are planned for June 16 with Hydro-lab.

Comments/observation:

Line name: Hydro Passage width (meters): 10 Passage Height (meters): 5 Passage Shape: Canyon, Phreatic tube Fauna: Shrimp Speleothems: Orange, stalactites, stalagmites, Sediment: Grey, organic, ripples, flat, percolation Infill: Swiss cheese, breakdown Water: Halocline near floor, mid passage, ceiling Additional Comments: 1. There‘s a possibility to find a short cut around the breakdown before “Shells”. A few

163 restrictions make travelling with scooters challenging through that area. 2. An extra 2 safeties were dropped 1000ft in. The change in water condition during the first dive of the project re-enforces the necessity for more bailout gas in this area of the cave. 3. Water temp in shallower dome sections is confirmed warmer than other part of the cave with hydro-lab measurement. 4. Salt-water layer in the first part of the cave was milky again. This has been already reported a few times. However, the fresh-water lens was unusually clear. 5. There’s a need for bigger backgas cylinders. 6. Per did a great job with surface support. There’s a necessity to further the procedures for surface support team before next SK project.

Equipment and Survey: 1. 5 stages (1 safety dropped a 1k) & 2 scooters (33 amp)/diver. 2. 35 minutes to 1st T & first stage drop & scooter switch 3. Dropped scooters before “Shells” restriction 4. Start exploring with 1 full stage & 2000 psi in other stage 5. Survey in ok.

Dive log:

Dive # 36

Time in: 11h00 Time out : 15h35 Total run time: 275 minutes Max Depth: 72feet Av Depth: 55 feet Total Exploration: 1,539 feet Divers: Fred, Danny Line Names: “Hydro”

164 165 Line Name Hydro Date Explored 15-Jun-06 Explored By Fred Devos, Danny Riordan Surveyed By Fred Devos Tie in Station Shells Line #32

MAX Depth in Feet 74 MIN Depth in Feet 53 Total Dist in Feet 1539

MAX Depth in Meters 22.42 MIN Depth in Meters 16.06 Total Dist in Meters 466.36

FROM TO Station Depth DIST Azimuth COMMENTS # (Feet) (Feet) IN 0 0 1 1 63 50 287 >SK 51,START 1 2 2 60 56 325 2 3 3 53 44 278 3 4 4 56 55 24 4 5 5 59 24 8 5 6 6 57 27 318 NWflowSE 6 7 7 58 48 330 NWflowSE 7 8 8 67 73 341 STAGE DROP 8 9 9 69 30 18 9 10 10 66 22 316 10 11 11 64 20 348 11 12 12 63 120 298 12 13 13 62 54 221 13 14 14 67 56 185 14 15 15 64 70 186 15 16 16 69 50 226 HUGE PASSAGE 16 17 17 68 38 252 17 18 18 64 10 270 R 18 19 19 61 40 284 R 19 20 20 58 78 282 20 21 21 73 55 258 HUGE PASSAGE 21 22 22 74 108 230 22 23 23 74 69 234 !NNW!DEEP 23 24 24 66 58 236 24 25 25 60 30 274 25 26 26 61 64 316 26 27 27 62 120 262 27 28 28 64 70 247 28 29 29 63 END,>YC'05 032

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Diving Operations June 16th, 2006

Dive Team: Fred Devos, Daniel Riordan, Per Thomsen

Surface Support: Sam Meacham, Roberto Chavez.

Dive site Name: Entrada Caapechen (Cenote Manati) Coordinates: UTM (WGS84): 16 Q 449018 2220411

Conditions: N/A

Dive Objectives: 1. Science dive with hydro lab 2. Water sample 3. Photo shoot 4. Remove safeties from the cave 5. Re-survey first 1000ft of cave.

Summary of results: 1. Profile of the water column taken with hydro-lab in the following area of the cave: entrance; first T; Silica Dome; 400ft down left side of T. Science work station will be indicated on stick map. 2. Water samples were taken at the same spots that the hydro lab measurement in the cave. A total of 11 water samples were collected at varying depth. 3. 160 pictures were taken during the dive. Danny mentioned that 1/3 of it came out good. 4. Safeties removed from cave ok. 5. Re-surveyed first 1000ft of cave ok.

Possible follow up:

1. More science work. This is a key aspect of the project. 2. More documentation. We need to always dedicate a few dives/project for photo & video documentation.

Comments/observation:

Line name: Passage width (meters): Passage Height (meters): Passage Shape:

June 16 Dive Data 168 Fauna: Speleothems: Sediment: Infill: Water: Additional Comments: 1. Next project in SK is planned for early Dec. 2. We need more dollies to carry equipment to the dock. 3. There’s a need for a proper up-line to be positioned in the middle of the cenote. 4. Penetration reel will be run from beginning of ML to up line & deco gas.

Equipment and Survey: 1. Field survey sheet & comments need re-doing to include more relevant information about the dives & water condition in the cave. 2. There’s a need to work on all scooters during summer break.

Dive log:

Dive # 37

Time in: 12h15 Time out : 17h05 Total run time: 290 minutes Max Depth: 72 feet Av Depth: 50 feet Divers: Fred, Danny, Per Line Names:

June 16 Dive Data 169 170

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The Sian Ka’an Biosphere Reserve

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Overview of Sian Ka’an Biosphere Reserve (Reprinted with the permission of El Centro Ecologico de Sian Ka’an)

The Sian Ka’an Biosphere Reserve (Figure 9) was established on the 20th of January 1986 by presidential decree (under President Miguel de la Madrid Hurtado) and became part of UNESCO’s Man and the Biosphere (MAB) program that same year. In 1987 the reserve was declared a UNESCO World Heritage Site. As part of the MAB program, Sian Ka’an faces the greatest challenge of conservation: to find a way to integrate human activities without compromising other forms of life contained within its boundaries.

Sian Ka’an is approximately 1.3 million acres in size and spans 120 kilometers from north to south (comprising almost one third of the Caribbean coast of Mexico). In 1994 an area of over 200,000 acres to the south of the Reserve was named a Protected area of Flora and Fauna of Uaymil, increasing the continuous area of protected land.

The Sian Ka'an Biosphere Reserve (from TNC website) Figure 9

The reserve contains three large core zones where human activity is limited by permission to scientific research. These areas, known as the Zonas Nucleares of Muyil, Cayo Culebras, and Uaymil, cover a total area of almost 700,000 acres. Low-impact human activities and sustainable development occur in the area of the reserve known as the buffer zone. The human population is estimated at 2,000 inhabitants, the majority of which are located in the coastal regions, especially in the fishing villages of Punta Allen and Punta Herrero. Approximately one percent of the land within the reserve is privately owned.

There are five entrances to the reserve, located at Pulticub, Santa Teresa, Chumpón, Chunyaxché and Chac Mool. Guards employed by the governmental SEMARNAP organization are stationed at every entrance to enforce the Reserve regulations.

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"Sian Ka’an" is translated from Mayan as "where the sky is born" or "gift from the sky". The reserve is thought to have been inhabited in the pre-Classic and Classic periods as part of the chieftainships of Cohuah and Uaymil. There are twenty-three known archeological sites inside the reserve. Discoveries of human remains, ceramic pieces, and other artifacts have been dated up to 2,300 years old. The northernmost section of Sian Ka’an contains what is thought to be an ancient trade route through lagoons and mangrove channels between the cities of Tulum and Muyil. Parts of what is now the Reserve were once areas of chicle production and trade through the middle of the twentieth century, and the fishing industry is still one of the most important economic activities of the Reserve’s population. Common species include spiny lobster (Palinurus espinosa) tarpon, grouper, permit, nurse shark, hammerhead, black tipped shark, and snapper. Tourism is another source of income for fishermen in Sian Ka’an, hired to run boat trips to see the reefs and lagoon systems. Approximately 36,000 tourists entered the reserve in the year 2000, and those numbers are expected to increase significantly for the year 2001. There is a charge of $ 4 USD as a fee entrance to the Reserve per person per day.

Habitats found in the Sian Ka’an Biosphere Reserve (Reprinted with the permission of El Centro Ecologico de Sian Ka’an)

Coral Reef The boundaries of the Sian Ka’an Biosphere Reserve include 110km of the second largest barrier reef in the world, which extends onward past Belize and Honduras. The reef is home to many important and several endangered species. Uncontrolled development along the Caribbean coast of Mexico has placed the reef in grave danger, as it is easily damaged and not so easily restored.

Beaches The beaches of Sian Ka’an constitute a very important habitat and nesting grounds for many species of wildlife, as well as serving as an important transition between land and ocean. Most notably during the months of May through August, the beach is a nesting ground for 4 endangered sea turtle species that have lost important nesting sites along many parts of the Caribbean coast.

Dunes The coastal dune is an important protector of inland habitats, especially during storms. Coastal vegetation includes Coccoloba uvifera, Tournefortia gnaphalodes, Suriana maritima, Sesuvium portalacastrum, Ambrosia hispida, Ipomoea and many other species. (For a more complete list, refer to flora link).

Wetlands Mangroves, savannas, swamps and marshes are all included within the classification of “wetland”. Water plays a vital role in the existence of each of these habitats, whether it be fresh, salty, or brackish. Wetlands line the coast of Sian Ka’an, playing an important protective role as a type of buffer between the ocean and the land that can absorb the impact of storms. Wetland areas contain immense biological diversity and are home to a 175 number of endangered species. Evident in all inundated wetlands is a conglomeration of algae known as periphyton that is believed to play an important role in the dissolution of calciferous soils, as well as being an invaluable source of food for many species of fish, mollusks, and insects.

Mangroves Four species of mangrove line the coastal areas of Sian Ka’an. The mangrove communities are critical for the survival of many species of fish, birds, insects, reptiles, and other plants. Many species of mangrove filter contaminated water and trap loosened sediment, making them protectors of the coral reef and other littoral habitats. The mangrove species found within Sian Ka’an are Rhizophora mangle (red mangrove), Avicennia germinans (black mangrove), Laguncularia racemosa (white mangrove), and Conocarpus erectus (buttonwood mangrove).

Savannas Coastal savannas are large areas of low-lying land with sparse, oxygen-poor soil that is inundated throughout much of the year. As few tree species have adapted to these conditions, savannas are dominated by species of grass, reeds, and rushes that rarely exceed three meters in height. Inland savannas contain shrubs and occasional trees in addition to grass, are drier and have a lower salinity. These environments are in danger of natural fires during the dry season.

Cenotes or Sinkholes Fresh water contained in the Yucatan’s underground aquifer carves away at the limestone above, weakening it and eventually causing it to give way. The result of this phenomenon is a unique habitat known as a cenote or sinkhole. Many cenotes remain connected with the aquifer and with other cenotes through underground passageways. Occasionally, however, cenotes are found to be completely isolated from other bodies of water and may contain fish and other wildlife that have evolved over time into completely distinct species.

Hummocks Petenes, or hummocks, are isolated areas of forest from several meters to several kilometers in diameter that are surrounded by swamps or inundated savanna land. These formations are found only in Cuba, the Florida Everglades, and the Yucatan Peninsula. There is often a cenote at the center of the hummock, which is surrounded by concentric circles of vegetation, from hardwood trees to grasses and rushes. Common species include cedar, mahogany, and zapote in the center ring, which are surrounded by various palm trees and the poisonwood tree, and eventually mangrove, rushes, and grasses. Many species of fauna live in hummocks, from insects to reptiles, mammals, and birds.

Tasistales A tasistal is a concentrated strip found within savanna land that contains the tasiste palm (Acoellorraphe wrightii), the grass Cladium jamaicensis, and occasionally other plant species such as poisonwood (Metopium brownei), buttonwood mangrove (Conocarpus

176 erectus), and cocoplum (Chrysalobanus icaco). The tasiste palm is extremely fire- resistant, and will survive natural fires that often strike savanna.

Fresh water lagoons The fresh water lagoons of Sian Ka’an are supplied with fresh water from the subterranean aquifer by small springs or cenotes. Found mostly inland, the fresh water filters toward the ocean in channels or through the surrounding wetlands. The lagoons are home to a number of species of fish and vegetation not found in the coastal areas.

Brackish water lagoons Ocean water and fresh water from inland and the aquifer meet and mingle in the brackish water lagoons along the coast of Sian Ka’an. These lagoons are lined with salt tolerant mangrove and grass species which provide a home to fish and mollusk species that make the area an attractive nesting ground for wading birds and residence of two crocodile species, Crocodylus moreletii and C. acutus.

Low tropical forest Many of the mammal species found within Sian Ka’an reside within the low tropical forestland which is located in the westerly portions of the reserve. The forests contain many hardwood species, including chechem, chicozapote, mahogany, tsalam, and other valued hardwoods. The environmental importance of these areas is increased by the international demand for hardwood that is pressuring many countries in the neotropics.

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Scientific Reports

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Detecting Subsurface Conduits with Electromagnetics

The following is an overview of the preliminary results of the geophysical surveys conducted in Quintana Roo in April 2006 by the students in environmental engineering Bibi Neuman and Malene Rahbek, Technical University of Denmark. The surveys are a part of their M.Sc. thesis “Modelling Concepts for the Sustainable Management of the Sian Ka’an Biosphere Reserve in Quintana Roo, Mexico”.

Background for the project

The 5280 km2 large Sian Ka’an Biosphere Reserve is a UNESCO World Heritage site, comprising a variety of ecosystems, such as tropical forests, wetlands, and coral reefs. The reserve hosts a rich biodiversity that encompasses endangered and threatened species. The hydrogeology of the area is karstic, with dissolution conduits, caves and sinkholes shaping a complex underground limestone aquifer. In the aquifer a thin freshwater lens rests atop saline water that extends under the entire peninsula. Due to a thin layer of highly permeable topsoil and the high porosity of the karst, infiltration to the aquifer is rapid and water is transported quickly towards the coast. The aquifer is therefore vulnerable towards pollution and gives a limited capacity for filtration of contaminants.

The water resources of the area are threatened by untreated domestic wastewater being injected into the aquifer as well as by an expanding tourism industry which is encroaching southwards towards the Sian Ka’an Biosphere Reserve. Local stakeholders, governmental and non-governmental institutions have expressed the need for the protection of water resources of the area and the need for further research on the area’s hydrological system.

The main objective of the M.Sc. project is to construct a regional hydrological model of the catchment which contributes with water to Sian Ka’an. A hydrological model is a computer based model that can simulate the groundwater flow based on data on climate, vegetation and geology. The hydrological model is a step in understanding the hydrological flow pattern in the catchment better, so that a more appropriate management of the water resources can be obtained in the long run.

An obstacle for developing an adequate hydrological model of the area is the limited knowledge about the location of the underground conduits which provide main transport pathways for the groundwater. The conduits are found in zones with high permeability and their diameter range from a few millimetres to several metres. The largest of these conduits are called caves when a person can fit into them. Cave systems have been explored and mapped by cave divers north of Sian Ka’an, and present explorations are now also targeting cave systems within the Biosphere Reserve. However, in order to be able to set up a representative regional-scale hydrological model it is crucial to identify zones of high permeability in the entire catchment that supplies water to the Reserve.

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This area is currently defined to be 43,000 km2 and comprises the main part of the state of Quintana Roo.

In the current project, satellite imagery, aerial photos and local knowledge has been utilized to identify potential zones of high hydrologic permeability on a regional scale. Subsequently geophysical measurements have been conducted over some of these features to investigate if higher permeability in these areas can be confirmed. The results of the ground-based geophysical measurements thus constitute an important part of the development of the regional-scale hydrologic model.

Electromagnetic geophysical surveys

Electromagnetic geophysical methods can be used for detecting underground conduits and zones of high permeability, because they utilize the fact that different geologic media, as well as different types of water in the geological matrix, have different abilities to conduct a current. By transmitting a current on the ground, an electromagnetic field will be created in the subsurface. The signal from this electromagnetic field can be measured and can be used to identify the material present in the subsurface as the strength of the electromagnetic field will vary with the conductivity of the material. Limestone has a very low conductivity, whereas freshwater and especially saline water has a high conductivity.

The equipment1 consists of two coils (a transmitter coil and a receiver coil) that are connected with a wire and separated with a coil spacing of 10, 20 or 40 m. The

1 EM34-3 XL by Geonics Ltd., Canada

180 penetration depth is approximately 75% of the selected coil spacing, with roughly half the signal coming from above this depth and half from below. The method produces point measurements in a transect over the desired feature. The objective of the surveys is to identify anomalies with high conductivity signals that deviate from the otherwise low background conductivity originating from the overall limestone geology, as this may be indicative of the presence of a large amount of water (in e.g. a conduit) within the waterfilled limestone medium. The conductivities can be read directly from the instrument, but a forward modelling analysis, which takes into consideration the physical characteristics of the different geological layers, may be applied to the results to support that a detected anomaly can be interpreted as a zone of high hydraulic permeability or even a conduit.

To test the ability of using the EM34 equipment for detecting conduits, a survey was carried out over a section of known cave, and showed a clear anomaly where the cave was located, at two independent measurement times, as illustrated on Figure 2. The measurement over the known cave thus confirms that it is possible to detect caves with the EM34 equipment. This result made it possible to survey three other locations in the area, where conduits/zones of higher permeability were expected. These survey locations are indicated on Figure 3, which also shows the extent of the currently defined catchment and the outline of the Sian Ka’an Biosphere Reserve.

20 m coil spacing

30 ) m

/ 25 S m (

20 y t i Cave 10-18m btl. v

i 15 t c u

d 10 n o

C 5

0 0 50 100 150 200 250 300 350 Distance from southern point (m)

20.04.2006 23.03.2006

Figure 2. EM34 measurement over known cave. The anomaly with values higher than 25 mS/m indicates the location of the cave. The background values are higher than found at other locations because the cave is located in a highly permeable area.

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Figure 3. Currently defined catchment area (red line) and the Sian Ka’an Biosphere Reserve (green line). Close-up of survey locations. Satellite images: Landsat.

The Vigia Chico Road Measurement

Figure 4a. The Vigia Chico Road transect. Red colour indicates the location of the anomalies. Brown dots are placed along the structures identified on the satellite imagery.

The first location is situated on the road between Felipe Carillo Puerto and Vigia Chico inside the Biosphere Reserve. By visual inspection of a satellite image this region had been found to host numerous structures that seem to approach the wetlands of Sian Ka’an from south-west, and it was therefore desired to investigate if this type of structure can be associated with zones of higher permeability. The identified south-southwest north- northeasterly directed structure is indicated with brown dots on Figure 4a, that also shows the length of the measured transect. Figure 4b shows the measured values on the location. 182

Vigia Chico Road

40 35

) 30 m /

S 25 m (

t 20 i v i t

c 15 u d

n 10 o C 5 0 0 1000 2000 3000 4000 5000 6000 Distance from northern end (meters)

20 m coil spacing 40 m coil spacing Figure 4 b. Measured values on the Vigia Chico Road transect.

On this Vigia Chico Road stretch it is seen that one large anomaly (values > 20 mS/m), can be detected at about 3-4000 m distance from the starting point, along with a smaller anomaly at about 4500 m distance. The locations of these two anomalies are marked in red on Figure 4a. It is seen that the largest anomaly seems to correspond very well with the identified structure. No obvious structure is found near the second anomaly, which could be due to it being very narrow.

Modeling of the measurements supports the interpretation of the presence of a high hydraulic permeability zone below the structure. The finding that the structure observed on the satellite image corresponds with an anomaly in the conductivity of the subsurface has interesting prospects for the regional scale hydrologic model. It means that inspection of satellite images can potentially be used to define zones of higher hydraulic permeability.

The Holbox Fracture Measurement

The second electromagnetic survey was conducted over an area located near the Holbox fracture zone, to investigate the correlation between this zone and conduit development/zones of high permeability. The location was selected based on inspection of aerial photos as well as accessibility considerations. The Holbox fracture zone is interesting because previous studies of the area has suggested that water flowing from the central part of the peninsula is “trapped” by the fracture zone and directed to the wetlands

183 at the ends of this zone at Holbox in the North and the Sian Ka’an in the South. Moreover, cave explorations have shown that cave development seems to be located mainly between the coast and this fracture zone. An EM34 transect was made along the Carrillo Puerto road north of Laguna Kan-Luum, in an area which had been identified as being atop the Holbox Fracture zone.

Figure 6a and b. The Holbox Fracture transect shown on a topographical map and an orthophoto respectively. Arrows indicate the Holbox Fracture zone and the red dot indicate the measured location on the topographical map. The red and green line indicates the measured transect on the orthophoto. Blue color indicates known open water bodies. Topographical map: Shuttle Radar Topography Mission (SRTM). Orthophoto: INEGI kindly provided by CINDAQ.

Figure 7 shows the results of the EM34 measurement on the Holbox Fracture transect. Background values of ground conductivity in the area is in the same range as on the Vigia Chico Road transect (9-15 mS/m). Two anomalies (values >15 mS/m) can be seen in the graph. The first is located about 1000 m from the southern end of the transect, whereas the second anomaly starts around 1900 m from the southern end of the transect and continues until the most northerly point measured, i.e. for 1000 m. The latter continued into the area where a large cave system is known to be. Modeling of the measurement supported the presence of high permeability zones at the location of the anomalies.

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Holbox Fracture transect

20 ) m / S 15 m (

y t i v i t

c 10 u d n o C 5

0 0 500 1000 1500 2000 2500 3000 3500 Distance from southern end (meters)

Figure 3.7. Apparent conductivity measured with the EM34 along the Holbox Fracture transect.

The Caapechen Measurement

Finally, a survey was conducted within the Sian Ka’an Biosphere Reserve, to investigate an area which at the time of the survey was subject to ongoing cave explorations of the cave system Sistema Caapechen. The surveys were undertaken in order to 1) attempt to find out which directions the explored northern branch of the cave would take and 2) assess the applicability of the method in the brackish water environment which constitutes a major part of the Reserve, by measuring over an already explored part of the southern branch. It was particularly interesting with respect to the cave explorations in this area to find out whether EM could be used to find caves as well, since dive explorations in this area have been made difficult due to the lack of cenotes and the resulting limited access to the cave systems.

The Caapechen South transect was made over water, using kayaks for holding and moving the equipment, whereas the Caapechen North transect was made on a small sandy/silty strip island covered with mangrove trees. Figures 10 and 11 below show the survey lines in relation to the explored cave and the results of the EM34 conductivity measurements.

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Figure 10a and b. The Caapechen South (over known cave) and North transects, respectively. Blue dots indicate background level values, pink dots indicate mediocre values (200 mS/m) and red dots indicate low values (180-200 mS/m). Yellow line displays currently explored cave (only direction, not width).

Caapechen South

300 280 ) m

/ 260 S m

( 240

y t i

v 220 i t c

u 200 d n

o 180 C 160 140 0 10 20 30 40 50 60 Distance from northern end (m)

Figure 11a. Measured conductivities on the Caapechen South transect.

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Caapechen North

300 280 ) m

/ 260 S m

( 240

y t i

v 220 i t c

u 200 d n

o 180 C 160 140 0 50 100 150 200 250 300 350 400 450 Distance from northern end (m)

Figure 11b. Measured conductivities on the Caapechen North transect.

As seen, the survey made over known cave (Caapechen South) did unfortunately not detect the cave as no anomalies (values deviate from background values) were measured. However, the Caapechen North results show one or two anomalies. The anomalies detected in this case have lower values than the background level, which seems reasonable to view as freshwater presence in brackish water keeping in mind the difference in conductivity of these two types of water. The location of the larger anomaly is marked with red dots on Figure 3.14 while the location of the smaller anomaly is marked with pink dots. As seen in Figure 10b the location of the largest anomaly could seem to be in continuation of the end of the currently surveyed line of the Caapechen.

Although the measured result seemed to give interesting indications, the forward modeling analysis unfortunately shows that it cannot be supported that the anomalies are caused by cave development, since in this kind of environment apparent anomalies may not be caused by e.g. the presence of conduits but instead may be an effect of small changes in porosity. In this environment, small changes in porosity may give large changes in the measured signal. This does not mean that there cannot be conduits beneath the transects, but their presence cannot be confirmed with geophysical methods based on measurements of electrical conductivity (or the inverse, resistivity).

The EM34 measurements over the Caapechen transects have thus shown that this method is not useful for detecting freshwater conduits in brackish water environments, and it has been made clear that although the measured signal at a first glance could look like anomalies caused by conduits, it is in fact not possible to say so based on the measurements.

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Future Plans for Research in the Area

Presently funding has been applied for to continue the ongoing M.Sc. project as a larger research project that goes by the name “Xplore – Exploration of Xibalba” and has the working title “Hydrogeophysical Methods for Integrated Water Resource Modelling of the Sian Ka’an Biosphere Reserve, Quintana Roo, Mexico”. It is an international cooperation initiative between Geological Survey of Austria, Technical University of Denmark and Swiss Federal Institute of Technology (ETH Zürich). The project is supported by Amigos de Sian Ka’an, National Commission for Protected Areas of Mexico (CONANP), The Nature Conservancy (TNC), Centro Investigador del Sistema Acuifero de Quintana Roo (CINDAQ), Centro de Investigación Cientifica de Yucatán (CICY) and Global Vision International (GVI).

The project aims to further develop the hydrological model for the catchment supplying water to the Sian Ka’an Biosphere Reserve. The man focus will be on determining the nature of the hydraulic connection between the Reserve and the Tulum area, which at this point still constitutes a crucial knowledge gap. The Urban Development Plan for the Tulum area as proposed by the Government of the Municipality of Solidaridad will bring extensive tourism development and urban development to this area and as the plan is presented at this point, the impact on the aquifer from increased water abstraction and increased waste water discharge will be enormous.

Refinement of the initial hydrologic model will demand higher resolution data on the conduit location than the interpretation of satellite imagery can supply. Therefore a survey using airborne electromagnetic methods for detecting the underground conduits is planned. The airborne survey is based on the same principles as the ground based method, but can cover a larger area in a much shorter time. The analysis of the ground based electromagnetic surveys suggests that the method is indeed very promising for detecting underground conduits in the karstic geology of the Yucatan Peninsula, except in the brackish environment found in the wetlands.

The ground based electromagnetic surveys have produced valuable data for use in the setup of the regional hydrologic model, as it confirmed that structures identified on satellite imagery are very likely to be associated with geological zones of high permeability, e.g. conduits.

The ground based measurements have thus shown very promising results for the planned airborne surveys of the Xplore-project. Therefore, it is our profound hope that it will be possible to raise the funding needed for the Xplore-project as soon as possible so that the project can be realized. The results of such a survey will be highly valuable, since an increased understanding of the hydrogeology of the Tulum area is crucial for the protection of the Biosphere Reserve, the Mesoamerican Reef and the unique cave systems that transport the water to these areas.

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For further information on the project and/or the geophysical investigations please contact Bibi Neuman ([email protected]) or Malene Rahbek ([email protected]). A copy of the M.Sc. project will be available upon request.

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