trucks, cementing trucks, perforators, acid suppliers, and high-pressure pump 

 trucks. These heavier vehicles may necessitate periodic maintenance of roads. 

 All vehicle movement raises dust on the road, and the larger trucks in particu- 

 lar may be very noisy. There is a possibility that supply vehicles will spill 

 or leak materials en route to the wellsite. 



In areas inaccessible by automobile, the crew may be quartered on the 

 barge or ferried back and forth by boat. All supplies are moved by barge or by 

 small crew boats. Because of long distances traveled by crew vessels through 

 canals, the boats usually move at moderately high speeds of 32 to 40 km per hr 

 (20 to 24 mi per hr). The boats are often 7.5 to 14 m (25 to 45 ft) long and 

 are capable of displacing a large quantity of water at speed. The narrow, 

 restricted nature of the canals results in considerable water movement as these 

 boats move. Water is pushed to either side as the boat passes any point, and 

 the waves generated result in wave reflection back and forth for several minutes, 

 particularly in narrow channels with parallel banks. 



Barges and tugs do not move at the same high speeds as crew boats. However, 

 since these vessels have deep displacement-type hulls that push a great deal of 

 water aside, they also set up waves in canals that reflect back and forth until 

 dampened. In addition, the wash from the large slow-rotating propellers of the 

 ' igs and deep displacement of the vessels can result in significant stirring of 

 loose sediments in the bottom of the channel. In marine locations both types 

 of vessels move through the canals several times each day. 



In some areas where access is particularly difficult, helicopters may fly 

 into the area to transfer equipment or personnel. When there are wide straight 

 canals, float-planes may be used. The main effect of these aircraft is to add 

 to the noise in the area. 



Solid waste disposal . Unless given a specific variance, burning of solid 

 wastes is prohibited in Texas. Thus, most burnable solid wastes are hauled 

 away by truck. Burnable waste may be incinerated on sites in bays, and the 

 ashes may be dumped in the water. Solid wastes that cannot be burned include 

 cuttings, broken or spent equipment, and trash. Cuttings generally collect in 

 reserve pits in upland and some marsh sites. They are generally buried and 

 compacted after drilling. In particularly soft marsh areas, cuttings may be 

 removed by truck or barge. In open-water sites, cuttings may be disposed of in 

 the water if they are clean and free of oil. In cases where oil -based muds are 

 used, or if considerable oil appears with the cuttings, they must be cleaned 

 before they can be buried or placed in water. 



Liquid wastes. Sanitary facilities are usually provided by portable 

 toilets. The facilities must occasionally be replaced, or the holding tanks 

 must be flushed. Specialized vehicles for removal of these wastes periodically 

 drive to the wellsite to clean and refurbish the equipment. 



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