首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Municipal sewage is of relative]y recent origin as a pollutant. It was first brought to public attention in the 19th century by
Municipal sewage is of relative]y recent origin as a pollutant. It was first brought to public attention in the 19th century by
admin
2010-02-17
86
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.
In densely populated suburban areas, a danger exits from ______.
选项
A、streams that do not flow directly to open bodies of water
B、cesspools and septic tanks that contaminate water supplies
C、storm and waste disposal sewers that have been combined
D、the undesirable odors of sewage
答案
B
解析
此题为细节题。答案在最后一段的主题句中。线索词为“suburban”、“source of pollution”和“ground water”。
转载请注明原文地址:https://kaotiyun.com/show/pI9K777K
0
专业英语四级
相关试题推荐
Tomanyweb-buildingspiders,mostof【C1】______arenearlyblind,thewebistheiressentialwindow【C2】______theworld.,their
Inrecentyearsmoreandmorecompanieshaveinvolvedinthetideofincorporatingdownsizingthroughouttheworld.Downsizingi
Inrecentyearsmoreandmorecompanieshaveinvolvedinthetideofincorporatingdownsizingthroughouttheworld.Downsizingi
Thepressure______causesAmericanstobeenergetic,butitalsoputsthemunderaconstantemotionalstrain.
Thedefenseministerpromisedtokeepthepresident__________ofthesituationintheMiddleEast.
Whowastheinventorofchewinggum?
Researchershaveestablishedthatwhenpeoplearementallyengaged,biochemicalchangesoccurinthebrainthatallowittoact
Asinglestatusmayhavemultiplerolesattachedtoit,constitutingaroleset.Considerthestatusofapatientinahospital.
Whyisthemannotreallysurprisedthathisparentsaremoving?
Ifyoufeeltiredallthetime,youdon’tnecessarilyneedtogotobedearlier.Thesolutioncouldbeassimpleastakingafiv
随机试题
组织变革的动因有()
何人提出呃逆"治当降气化痰和胃为主,随其所感而用药"的治疗法则
治疗寒湿阻滞型胎黄的首选方剂是
关于招标信息的修正,下列说法中正确的有()。
通货紧缩是指物价持续下降,并伴随有经济的实际增长率高于潜在的可能增长率。()
在双侧限有偏移情况下,过程能力指数Cpk为()。
乐曲《梁山伯与祝英台》属于电子音乐。
适合原型化开发的准则很多,下列哪一项不是有效的准则?
设某二叉树的后序序列为CBA,中序序列为ABC,则该二叉树的前序序列为
OxfordUniversityoncefamouslyclaimedtohavebeenfoundedbyAlfredtheGreatinthe9thCentury.Butinfact,theUniversity
最新回复
(
0
)