Abstract:Waterlogging is an acute problem in the agricultural areas of arid regions. This study highlights the main reasons for water table rise in the Wafra agriculture area of South Kuwait. A two-tier aquifer system exists in the area, which consists of the Kuwait Group aquifer underlain by a semi-confined Dammam aquifer. Improper sealing of wells tapping the semi-confined Dammam aquifer and over-irrigation were the main reasons for water level rise, and an increase in total dissolved solids was due to high evaporation of brackish water used for irrigation in the area. Other issues such as thin soil cover, topographic variation, and geomorphology within the area play an interactive role in the development of salt crusts on the ground surface. The key solution to the problem lies with proper well design and irrigation management. The sealing of the wells tapping the Dammam Formation has resulted in the lowering of the water level, which has allowed the reclamation of farms. For sustainable management of the Wafra agriculture area, it is observed that only the Kuwait Group aquifer should be utilized for irrigation, dewatering should be carried out in selective low-lying areas, and the adoption of best irrigation practices can be the only way for sustainable agriculture development in the area. The use of tertiary-treated wastewater, along with groundwater from the Kuwait Group (KG) aquifer, can be a solution to sustain agriculture. The crop water requirement should be considered for irrigation application while using best practices such as drip irrigation.

Objective/Scope Achieve operational excellence in field of Electrical Submersible Pump (ESP) surveillance and optimization by benefitting Petroleum Development Oman (PDO) asset teams in identifying optimization opportunities, use of real time data for well test validation and improving overall asset KPIs (Key Performance Indicator) through a fully automated Well Management System (WMS). Methods, Procedures and Process The ESP well models are built and sustained in WMS by automated processes to update recent well model information from PDO corporate databases. WMS provides real time well and pump information, along with well model based calculated outputs, pump operational status, workbenches to validate well tests, design inputs, modeling sensitivities for users to perform daily tasks using well-defined standard operating procedures. Operating envelopes based Exception Based Surveillance (EBS) were improved by replacing them with pattern recognition based EBS to improve accuracy, avoid wastage of time and resources. Continuous hands on coaching were conducted to users to strengthen their skills. Benefits, Results, Observations, Conclusions Since implementation of WMS, it has maintained more than 1600 ESP well by building well models automatically for new or workover ESP wells successfully saving huge effort and time from engineers in gathering data and building model. Production Engineers have created more than 100 ESP design input datasheet using the WMS resulting in improved ESP design by avoiding human errors. WMS have already supported assets in identifying around 138 ESP wells with optimization opportunity resulting in increasing around 3 % net oil gain only in year 2017. Real time pump operational status calculation from WMS and sensitivity (Tubing Head Pressure and Hz) based operating point analysis reduced upthrust / downthrust ESP wells by ~50% across PDO in few months. Early detection through Pattern Recognition based EBS has resulted in minimizing ESP downtime by around 30% through quick realization of sub-optimum wells. Validating well tests utilizing downhole gauge data has helped in identifying dubious well tests because of faulty well test equipments thus saving time and money for sequencing the well for re-test and improving allocation. A proper tool and SOPs utilization tracking mechanism is already in place highlighting areas for continuous improvement. Novel Ideas The utilization of real time data and well model together has proven to be a unique and novel way in improving ESP surveillance and optimization for managing around 1600 wells. The replication of same methodology is already undertaken for Progressive Cavity Pump (PCP) and Beam Pump (BP) surveillance and optimization utilizing WMS for PDO assets.

The Wafra area is located in the southern part of the State of Kuwait constituting about 47% of the State’s total agricultural area. The expansion in Wafra area from 11.25 km2 in 1973 to 199.2 km2 in 2010 has led to excessive pressure on groundwater resources. The objective of this study was to examine the quality of the groundwater in terms of suitability for irrigation pertaining to specific quality standard indices. To achieve this, water samples were collected from 31 wells in Wafra Area. The samples were analyzed for salinity, cations, anions, and some heavy metals. Results indicated that the values of total dissolved salts )TDS(, electrical conductivity )EC(, chlorine )Cl-(, calcium )Ca+2(, and sodium )Na+( detected in water samples did not satisfy Kuwait, and GCC standards. The study revealed that 68% of the wells were highly saline while the rest were moderately saline according to FAO standards. According to Simsek and Gunduz )2007(, the water can be considered moderately suitable for irrigation. According to Richard )1954( standards the water is of type C4-S4 )highly saline and sodic( and not suitable for irrigation according to AOAD standards. Piper diagram and regression and correlations analysis indicated that sodium and chlorine are the dominant cations and anions. The analysis also revealed that the concentration of cadmium )Cd+2( in all the tested wells was higher than the standard concentration range of 0.01 to 0.05 mg/l and to a lesser extent nickel )Ni+2( and manganese )Mn+2(, violating the permissible limits. The results also showed an increase in total dissolved salts with time from 6984 ppm in 1989 and 7930 in 1998, reaching an average of 9211 by 2010. The study recommended encouraging adoption of modern agriculture techniques and reuse of treated wastewater, to protect soil and groundwater from salinization and to promote sustainable agricultural production in Wafra area as well as periodical check for heavy metal concentrations specially cadmium in groundwater.