be defined and a development plan can be made. Potential well sites may be 

 mapped, but other factors may determine whether an overall access plan is made. 

 Fields are not completely developed at one time. A few new wells may be drilled 

 in one portion of the field over a year or several years' time. This is dictated 

 by company policy and budget. By drilling wells only a few at a time, the 

 company may use new logging information to better select additional well sites. 

 Furthermore, it is very difficult to predict the amount and type of production 

 and transportation equipment needed for an entire field. It is more practical 

 for the producer to provide the necessary equipment and add to it as the needs 

 arise. Finally, the company generally will not make all of its investment in 

 one field, but it will try to diversify to several fields. 



As a result, field development does not lend itself to one-time planning 

 as do other types of developments - subdivisions, for example - with respect to 

 traffic access. Better information may result in changes of well site placement. 

 In an effort to keep costs down, the company will try to minimize dredging 

 distances, often dredging from one wellsite to next. This results in a "spider 

 web" of canals having complex and unpredictable effects on the environment. 



Site Preparation and Operation 



In coastal areas there is generally no limit on oil and gas activities 

 with respect to the time of year, except on refuges. Thus all phases of the 

 industry are accomplished year round. 



Location of drill sites is based on geologic judgment and experience. 

 Deviations from exact placement can be made by slant drilling. It is possible 

 to alter and control the direction of the cutting head as it moves down through 

 the strata. There are limits to this process related to the drilling depth, 

 nature of the formations, and extra stresses placed on equipment. More casing 

 and drill pipe are required to reach a particular depth; strains on pipe joints 

 and casing are greater; retrieval of broken equipment is more complicated. The 

 lateral distance that can be reached by directional drilling is limited and, 

 overall, the problems encountered increase considerably. Even so, there are 

 benefits to be gained. In areas with access problems, several directional 

 wells may be drilled from one central site, minimizing access and site prepara- 

 tion expense as well as environmental alteration. 



Numerous state and Federal regulations pertain to drilling, particularly 

 in marshes or shallow-water areas. In navigable waters, rules of the U.S. 

 Department of Transportation, Environmental Protection Agency, and U.S. Army 

 Corps of Engineers are applicable (e.g., 40 CFR 110.5). In Louisiana, the 

 Louisiana Stream Board and the Louisiana Wildlife and Fisheries Commission have 

 regulation authority, particularly for accidents, spills, and waste disposal 

 (see Title 56, chapter 3, Stream Control: 1451, 1452, 1461 , and 1462 

 for examples). In Texas, the Railroad Commission and Department of Water 

 Resources (formerly the Water Quality Board) have regulatory authority under 



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