Lecture 7: Case study:Phenol polluted aquifer

Question 1

Ground water contamination examples:

Answer 1

• agriculture (nitrogen fertiliser, manure spreading)
• road salt
• petrol stations
• land fill
• industrial storage
• leaking sewers

Question 2

___ is an important source of water

Answer 2

groundwater

- 30% of the UKs water comes from aquifers

Question 3

aquifers

Answer 3

a body of permeable rock which can contain or transmit groundwater.

Question 4

is water renewable?

Answer 4

• some water under ground can be 100’s of thousands of years old
• at the top may be few months, bottom v old
• so to pollute u pollute it for a long time

Question 5

pollution migration in a sandstone aquifer:

Answer 5

• permeable so easily contaminated and spreads through stone
• element of dilution

Question 6

solvent pollution migration in a chalk aquifer:

Answer 6

• chalk dense but has fissures and cracks
• if polluted with something like solvent, if doesn’t dilute into water will sink to bottom and just sit there at the bottom and pollute for years
• cant just pump and treat

Question 7

sort of __ and sort of __ it goes into is important

Answer 7

pollutant and rock

Question 8

wolverhampton bore holes extraction

Answer 8

by puling water from bore hole u accelerate groundwater flow, so in years to come bore hole will be contaminated

Question 9

how many sites are polluted in UK alone

Answer 9

50,000

Question 10

how did wolverhampton groundwater become polluted

Answer 10

• coal tar distillate plant developed in 1950’s
• caustic soda lime kilns closed in early 1980’s
• now organic chemical plant

Question 11

problems w pollution in the past

Answer 11

unknown whats gone down there (in 50’s and 60’s)

Question 12

wolverhampton site is a ___ aquifer

Answer 12

sandstone

Question 13

wolverhampton aquifer contaminated plume will hit bore hole in

Answer 13

bore hole is 2km away

- plume hit in 50-60 years time

Question 14

how do we manage the plumes progress

Answer 14

• drill bore holes
• many
• build up a map of what is happening under ground
• pool of phenols and organic C which near surface are severe, but microbes still there, diffuses out

Question 15

Natural Attenuation

Answer 15

• sometimes cleaning causes more damage than leaving it alone
• dilution, dispersion, evaporation, adsorption to surfaces & BIOLOGICAL TRANSFORMATION & DEGRADATION
• • so if microbes will degrade them, instead of bringing pollute to surface and costs for all this, so sometimes we just leave it
• = monitored natural attenuation to document the progress

Question 16

the success of Natural Attenuation

Answer 16

varies

• BTEX
• • common pollutant near petrol stations, NA effective
• MTBE
• • additive to petrol as replacement to lead, NA ineffective

Question 17

what route do microbes take to degrade organic compounds

Answer 17

many routes!

• both anaerobic and aerobic
• • anaerobic can use different terminal electron acceptors
• • majority of these areas are go anaerobic as oxygen is used up so quickly

Question 18

TEAs used in microbial action degradation

Answer 18

• oxygen is used up on outer plume v quickly
• then iron
• sulphate
• methanogenics (archaea)

Question 19

multilevel sampler: 2 methods to gain data

Answer 19

• pump groundwater from different depths (planktonic community)
• lower a sandbag into the borehole and leave for 18 months (attached community)

Question 20

16S rRNA data using cultured and environmental samples

Answer 20

• culture gave imprecise measure of what is there
• • some things dont like being cultured
• • some cant be cultured
• by looking at environmental samples aids us in describing the process’ going on underground
• • sulphate reducers –> probably reduces sulphate
• • methane oxidisers –> oxidise methane which comes from archaea

Question 21

attached communities ___ markedly from planktonic communities

Answer 21

differ