首页
登录
职称英语
Municipal sewage is of relative]y recent origin as a pollutant. It was firs
Municipal sewage is of relative]y recent origin as a pollutant. It was firs
游客
2023-11-20
27
管理
问题
Municipal sewage is of relative]y recent origin as a pollutant. It was first brought to public attention in the 19th century by a London physician who showed that the city’s cholera outbreak had been caused by just one contaminated well. Even though the contamination of drinking water by disease germs has been nearly eliminated in this country, hundreds of communities are still discharging raw sewage into streams and rivers.
When we consider that this sewage contains effluents from toilets, hospitals, laundries, industrial plants, etc. , then the potential of the pollutants as a health hazard is apparent.
The problem of municipal sewage disposal is complicated by the fact that, years ago, most cities combined their storm and waste disposal sewers. Many of these combined systems work well, but others cannot cope with sudden heavy rains. When such storms occur, water mixed with sewage may flood and disable treatment plants unless bypassed, untreated, into a stream. In either case; the people may have little protection for several days from these wastes that may contain disease germs.
Even if adequately treated to eliminate the health hazard, sewage is aesthetically undesirable because of odors and colors produced. Detergents have posed a particular disposal problem. Although there is no indication that they are injurious to health, they can cause foaming, which can clog treatment plants and, at the least, spoil the scenic beauty of streams.
Rural and suburban residents should be aware that septic tanks and cesspools are a potential source of pollution to ground water supplies. This is especially true in the suburban areas with a high population density and with
no municipal sewage disposal and treatment system available. In some areas, sewage disposal is accomplished by cesspools. Soil research is furnishing guidelines for more effective and safer use of systems such as these. [br] This passage is concerned primarily with the ______.
选项
A、problems of waste disposal
B、dangers of drinking from wells
C、turbidity of polluted water
D、outbreak of cholera
答案
A
解析
此题为主旨题。线索词为“sewage”、“pollutant”、“sewage disposal”等,这些词贯穿文章始终,可见A项符合题意。B、C、D三项皆为文中细节,不能反映主题。
转载请注明原文地址:https://tihaiku.com/zcyy/3204069.html
相关试题推荐
Howmanyattacksandclasheswerereportedinthisnews?[br][originaltext]
Howmanyattacksandclasheswerereportedinthisnews?[originaltext]Atta
Accordingtothecourtruling,Israelhasto[br][originaltext]TheInterna
Accordingtothecourtruling,Israelhasto[originaltext]TheInternational
WhichofthefollowingisNOTtrueabouttheAUpeacekeepingforce?[originaltex
Wheredoesthisconversationmostlikelytakeplace?[br][originaltext]M:Hell
Wheredoesthisconversationmostlikelytakeplace?[originaltext]M:Hello.May
Whatisthemaintopicofthisconversation?[br][originaltext]M:Weseemtob
Whatisthemaintopicofthisconversation?[br][originaltext]M:Weseemtob
[originaltext]LetChildrenLearntoJudgeTheirOwn
随机试题
AslongastheAmericanlandwasnotcompletelysettledandtheelementsof【
It’sveryinterestingtonotewherethedebateaboutdiversity(多样化)istaking
Whichofthefollowingsentencesexpressesapassivemeaning?A、Bellinventedthe
[originaltext]W:Jack,wouldyouminddrivingmetothestation?M:Sure,why
在相关图法中,下列图形称之为( )。 A.强正相关 B.强负相关 C.不
痹证关节疼痛日久肿胀局限或见皮下结节者为A.瘀 B.热 C.风 D.湿
清道夫受体有广泛的配体谱,其配体的共同特点是A:都为多阴离子化合物B:都含有A
( )是指当对一个人的某些特性形成好或坏的印象之后。人们就倾向于据此推论其他方
波浪理论考虑三方面的因素,其中,()是最重要的,也是波浪理论赖以生存的基础。A:
(2019年真题)根据《标准设计施工总承包招标文件》,关于责任保险的说法,正确的
最新回复
(
0
)