VOA慢速英语20060515a
时间:2019-01-30 作者:英语课 分类:2006年慢速英语(五)月
DEVELOPMENT REPORT - Need to Dig a Well? Start HereBy Gary Garriott
Broadcast: Monday, May 15, 2006
This is Shep O'Neal with the VOA Special English Development Report.
There are several low-cost ways to dig or drill a well to get water out of the ground.
One method is to make a hole by turning a large drill bit device 1 by hand, over and over again, into the ground. From time to time, the drill bit must be lifted to the surface and cleared of soil. This method is good for most kinds of earth, but not for rocks.
Child drinking from a water fountain
Holes of twenty-five meters deep can be made in this way. It usually takes four to six people working as a team. Drilling in this way usually goes quickly for the first five meters or so. But after that, it is much slower. Parts of the drill bit and connecting machinery 2 have to be taken apart each time the drill is brought to the surface.
More complex equipment use machines to power the drill bit. These machine-driven drill bits have structures that look like moving teeth.
Sometimes the drill bit hits large stones or rocks. If this happens, the well may not be straight down into the ground. The well may still be usable as long as the hole is mostly straight, especially in depths of thirty to sixty meters.
Another way to dig a well is limited to going about twenty meters deep for a hole fifteen to twenty centimeters across. This method uses a heavy metal container that is dropped into the hole again and again. It looks like an empty can. The action of hitting the dirt breaks up soil and rocks. As it hits the dirt, the soil and rocks fill up the container. It is brought to the surface and emptied, and then lowered again.
Sometimes wells can no longer be used because they are not straight enough, or they no longer produce water, or the water is too dirty. If a well is no longer used, it must be closed to keep people from using it and to keep small children or animals from falling in.
The best way is to fill the well with clay soil up to about one meter from the top. From there to the top it should be filled with concrete.
You can get more information about digging and drilling wells from VITA, Volunteers in Technical Assistance 3, now part of EnterpriseWorks/VITA. The Web site is v-i-t-a dot o-r-g.
This VOA Special English Development Report was written by Gary Garriott. Read and listen to our reports at www.unsv.com. And if you would like to send us e-mail, write to special@voanews.com. I'm Shep O'Neal.
- The device will be in production by the end of the year.该装置将于年底投入生产。
- The device will save much time and effort for us.这种装置会使我们节省大量时间和气力。
- Has the machinery been put up ready for the broadcast?广播器材安装完毕了吗?
- Machinery ought to be well maintained all the time.机器应该随时注意维护。
- She called and called but no one came to her assistance.她叫了又叫,但没有人来帮。
- He will get the great possible assistance.他将获得尽可能大的帮助。