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
2024-10-26
33
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/3818631.html
相关试题推荐
Howmanyattacksandclasheswerereportedinthisnews?[br][originaltext]
Howmanyattacksandclasheswerereportedinthisnews?[originaltext]Att
WhatdoesthenewssayaboutthepresidentialelectioninIndonesia?[originalte
Accordingtothecourtruling,Israelhasto______.[br][originaltext]Th
Whatisthemaintopicofthepassage?[originaltext]Letmegetstraightto
Thispassageismainlyabout______.[br][originaltext]Everyyearsharks
WhydidthewomangotoHongKong?[br][originaltext]M:Hi,Maggie!Haven’tse
WhydidthewomangotoHongKong?[br][originaltext]M:Hi,Maggie!Haven’tse
Whatisthemaintopicofthisconversation?[br][originaltext]M:Weseemtob
Municipalsewageisofrelative]yrecentoriginasapollutant.Itwasfirs
随机试题
Iftheyhadinformedusinadvance,we______hereearlier.A、wouldcomeB、wouldha
【B1】[br]【B6】[audioFiles]audio_eufm_j01_259(200910)[/audioFiles]impression此处缺少
警惕:“弱势群体”利益在“最小化”,改革必须重视“利益”的走向问题,必须重视因改
关于肿瘤的发病因素的说法错误的是()A.吸烟与恶性肿瘤关系密切 B.恶性肿瘤
经脉循行联系上齿的为A.足少阴肾经 B.手阳明大肠经 C.足少阳胆经 D.
李某,男性,34岁。有慢性咳喘病史5年,外出感寒后,出现咳逆喘息。现症见:喘息咳
利用历年城市人口的年平均增长量数据,通过复利公式,计算预测期限可能达到的发展水平
下列哪个情形不属于可以直接判定为重大火灾隐患()。A.商店营业厅内的疏散距离超过
共用题干 男,58岁。上前牙反复肿痛4年,要求诊治。年轻时左上前牙有洞曾在医院
某厂房结构内靠近围护结构处的室内声级为90dB(A)(1000HZ),透声面积
最新回复
(
0
)