Hurricane Roxanne and a New Assessment Criteria for Bay of Campeche

Abstract Production from Bay of Campeche constitutes a significant percentage of the wealth of Mexico. One of the primary objectives of PEMEX is to assure that this production is not interrupted. In 1995 hurricanes Opal and Roxanne passed through Bay of Campeche (BOC). Opal did not cause any noticeable damage. Roxanne on the other hand was the most severe hurricane recorded in the Bay of Campeche in this century. Its anomalous behavior and the resulting extreme environmental conditions did considerable damage. PEMEX implemented a rapid repair program and was able to bring the production back to its normal levels within two months. Subsequently, PEMEX jointly with Instituto Mexicano del Petr]ó1eo (IMP), launched an extensive program to inspect, assess, and repair the facilities. Results of the initial assessments indicated that the assessment parameters as well as the metocean criteria utilized were not suitable for Bay of Campeche. A detailed risk study considering the site specific conditions and requirements was performed. Utilizing probability based risk assessment techniques a new criteria. known as the "transitory' criteria" was developed. The transitory criteria was then used to re-assess the platforms and pipelines in the Southwest Marine Region of BOC. Introduction Mexico first began exploration of offshore hydrocarbon deposits of the coasts of Tampico, Tamaulipas and Poza Rica in 1965. The results of these early explorations were extremely satisfactory. Consequently PEMEX increased the offshore activities and started to install and drill from fixed platforms. Initially ten platforms were installed. The program was very successful, as one of the wells reached a production level of 26,000 barrels per day. These early platforms are still in operation and jointly they produce 23,000 barrels a day. After a period of slowing down, offshore activities started again in 1975, this time at Campeche Sound in the Bay of Campeche (BOC), located 80 kms to the North East of Ciudad del Carmen island. Here, the first exploration well Chac I was drilled to a depth of 3,567 m below the sea bed. Oil was found in commercial quantities in calcareous rock. This discovery was the starting point for further explorations which resulted in discovering the Cantarell field, which includes the Akal complex, and the other producing fields such as Ku, Abkatum, Caan, Chuc, Pol, Chac, Taratunich, and others as shown in Fig. 1. All facilities installed since 1978 are fixed platforms andcan be grouped in accordance with the function they are performing, as illustrated in Fig. 2. The production from the Campeche Bay is handled through a wide network of pipelines as illustrated in Fig. 3. Today in the Campeche Bay PEMEX has more than 200 platforms and approximately 1900 kms of pipelines. Distribution of the products for domestic consumption and export to overseas is achieved through the facilities located at Dos Bocas, Cayo Areas and Atasta as shown in Table 1 and Fig. 4. Bay of Campeche- Production and Economics Drilling activities carried out in BOC in the years 1994, 1995 and 1996 are summarized in Table 2. In 1996, 2,630,035 meters of drilling was accomplished. Approximately 750 wells were drilled which included exploration, development, dry and accidental wells.