RESEARCH ON THE STANDARDS OF THE TREATED WASTEWATER REUSE SYSTEM
A. Tajima, K. Sakurai and M. Minamiyama
Wastewater and Sludge Management Division, Water Quality Control Department
Project period: 2001-2005

OBJECTIVESIn Japan, since the first reuse of treated wastewater as toilet flushing water was undertaken in 1980 in Fukuoka City inresponse to the severe drought in 1978, treated wastewater has been used as toilet flushing water, snow melting water,
environmental water, industrial water, sprinkling water and for a variety of other uses. However, only 200 million m3 peryear of treated wastewater from 246 wastewater treatment plants (WTPs) is being reused outside the plants, which is lessthan 2% of the 1.4 billion m3 of effluent from 1,924 plants in FY 2003. It is expected that such applications will increasein the future from the viewpoint of saving water resources in urban areas, which will in turn increase the importance ofappropriately reusing treated wastewater.
Therefore, care must be taken to maintain the appropriate color, turbidity, odor, and other aesthetic elements of reclaimed
wastewater so that it is not unpleasant for users, and suitable measures taken to prevent corrosion, clogging, and otherproblems that impair the functions of the treated wastewater reuse system.
For the above reasons, the Sewerage and Wastewater Management Department of the Ministry of Land, Infrastructure
and Transport and the Water Quality Control Department of the National Institute for Land and InfrastructureManagement decided to revise the water quality standards and the water quality targets stipulated in the previous
guidelines and manuals for the reuse of treated wastewater. And, in order to establish new standards from the viewpointof appeal and acceptance, these organizations have carried out the surveys on users’ consciousness to the reuse of treatedwastewater. This report presents the results of the surveys and the results of studies on new standards based on thesesurveys.

MATERIALS AND METHODS
Table 1 Methods of survey
Category of use

Toilet flushing water

Landscaping water / Recreational water

Period2003.12 – 2004.2

2004.7

2003.12 – 2004.1

2004.7

Number of survey location

7

3

4

3

Number of people who

1,124

734

731

482

answered
Measured items of water quality

Turbidity, color and odor

It is important to investigate users’ taste for the reclaimed wastewater in order to study the criteria on appeal and acceptance ofthe reclaimed wastewater because there is close relationship between the appeal and acceptance of the reclaimed wastewaterand users’ taste. Therefore, in order to study the influence of turbidity, color and odor of the reclaimed wastewater on the users’
taste, the survey on users’ taste for turbidity, color and odor of the reclaimed wastewater was performed at the facilities wherereclaimed wastewater is used. The method of the survey is shown as Table 1 and the questionnaires were handed to the users

11directly at the survey location or by mail. We dealt the answer in case of just looking at the surface of water as landscaping
water and the answer in case of touching the water as recreational water.

RESULTS
Through the survey and the study, we acquired the following knowledge.
(1) The ratio of users’ acceptance of color, clearness and odor for landscaping water are 64-84%, 63-82% and 72-86%
and the ratio of those for recreational water are 55-81%, 51-78% and 57-79%,while the ratio of those for toilet flushingwater are 89-98%, 89-97% and 85-96%. These results show that the ratio of those for landscaping water and recreational
water disperses more than those of toilet flushing water. The reason may be that there are big differences of facility types
among each location and differences among users’ taste.
(2) There was no definite relationship between the users’ preference and the reclaimed wastewater quality (color,
turbidity and odor) because of the difference among users and influence of facility type, etc.
(3) It is preferable that the criteria from the viewpoint of appeal and acceptance be set based on the regional users’ wishes dueto the difference among users and influence of facility type, etc.

100

80

Users’ acceptance (%)

80

容認度（％）

Users’容認度（％）
acceptance (%)

100

60

修景用水（冬）Landscapeuse (winter)
Recreationaluse (winter)
親水用水（冬）Landscapeuse (summer)
修景用水（夏）Recreationaluse (summer)
親水用水（夏）Toiletflushing (winter)
水洗用水（冬）Toiletflushing (summer)
水洗用水（夏）4020

修景用水（冬）Landscapeuse (winter)
Recreationaluse (winter)
親水用水（冬）Landscapeuse (summer)
修景用水（夏）Recreationaluse (summer)
親水用水（夏）Toiletflushing (winter)
水洗用水（冬）Toiletflushing (summer)
水洗用水（夏）

60
40

20

0

0
0

5

10
色度（度）

15

20

0

0.5

認度（％） (%)
Users’容acceptance

1.5

Fig.1 Relationship between the color and theFig.2 Relationship between the turbidity and theusers’ acceptanceusers’ acceptance

100

80

60

修景用水（冬）Landscapeuse (winter)
Recreationaluse (winter)
親水用水（冬）Landscapeuse (summer)
修景用水（夏）Recreationaluse (summer)
親水用水（夏）Toiletflushing (winter)
水洗用水（冬）Toiletflushing (summer)
水洗用水（夏）

40

20

0
0

1
濁度（度）
Turbidit
y

Color

10

20

30
臭気強度

40

50

60

Odor

Fig.3 Relationship between the odor and theusers’ acceptance

122

APPLICATION OF LCA TO WASTEWATER SYSTEM
M. Minamiyama, Y. Aratani and R. Hiraide
Wastewater and Sludge Management Division
Project period: FY2001-2004

OBJECTIVES
Recently, it has become necessary to evaluate the impacts of public works projects on the environment from theviewpoint of global environmental protection. Life-cycle assessment (LCA) is an effective method for such evaluations.
This research examined the application of LCA to wastewater projects. The environmental load of CO2 emissions(LC-CO2) and energy consumptions (LCE) were calculated over the four life-cycle stages of a wastewater system:
construction, operation and maintenance, recycling and reuse, and scrapping.
In FY 2004, we analyzed the possibility of simplifying life-cycle inventory (LCI) analysis in the LCA process for
wastewater treatment systems and the effects of updating input-output tables (I-O tables) on the primary unit load andresults of LCI analysis.

METHODS(1) Simplification of LCI analysis for wastewater treatment system
Our previous studies on the characteristics of environmental load of wastewater treatment systems showed that most of
the environmental load derives from electricity consumption of some main equipment during the operation andmaintenance stage in the life-cycle of wastewater treatment systems. In this study, we tried to simplify the LCI analysis
for the oxidation ditch (OD) process. We calculated LC-CO2 and LCE for four wastewater treatment plants treated by theprocess and analyzed the relationship between the environmental load and electric power of the equipment used.
(2) Effects of updating I-O tables on primary unit load and results of LCI analysis
The primary unit load for LCI analysis is generally based on the unit load taken from I-O tables in Japan; in ourprevious studies, the primary unit load from the 1990 edition of the tables was used. I-O tables are updated every five
years and the 1995 edition is now publicly available. In this study, we analyzed the effects of changing the primary unitload resulting from the I-O tables being updated from the 1990 edition to the 1995 edition on the results of LCI analysis
for wastewater treatment systems, calculating LC-CO2 and LCE at the operation and maintenance stage for four
wastewater treatment plants which have various types of treatment process and treatment capacities.

RESULTS(1) Simplification of LCI analysis for wastewater treatment system
In this case study, aeration equipment (blower, mixer) was selected as having the greatest influence on theenvironmental load among the equipment of wastewater treatment plants using the OD process. Table 1 shows asummary and the environmental load for the four plants. As shown in Fig. 1 and Fig. 2, there are positive correlations
between the output (kW) of the aeration equipment and LC-CO2 and LCE. These relations indicate that if the output of
aeration equipment is known, the environmental load can be simply calculated. According to our previous studies, most13

Table 1 Summary and environmental loads of four wastewater treatment plants

Treatment plant1)

A

D

30

194

30

78.4

Horizontal shaft

Vertical shaft

Diffuser and propeller

8.90×102
1.80×104

1.54×102
3.11×103

5.14×102
9.46×103

1.56×102
LCE (GJ/year)
3.04×1031) Oxidation ditch process
2) Data in FY 2002

LC-CO2 (t-CO2/year)

1,000

20,000800

16,000
LCE(GJ/year)

LC-CO2 (t-CO2 /year)

C

Vertical shaft

2)

Output of aeration (kW)Type of aeration

B

600

400

12,000

8,000

4,000

200

0

0
0

50

100

150

200

0

250

50

100

150

200

250

Output of aeration(kW)Output of aeration(kW)Fig. 2 Output of aeration and LCE

Fig. 1 Output of aeration and LC-CO2of the environmental load of other types of treatment process except OD derives from electricity consumption of somemain equipment at the operation and maintenance stage in the life-cycle, too. By capturing the LCI analysis data for othertypes of treatment process, it may be possible to clarify the relationship between the main equipment and theenvironmental load for each type of treatment process. When it is necessary to evaluate the impacts of the wastewater
treatment process in terms of global environmental protection assuming that the information and data for LCI analysis arelimited as projects are planned and facilities are designed, these relationships could be used to simply calculate theenvironmental load.
(2) Effects of update of I-O tables on primary unit load and results of LCI analysis
With the updating of the primary unit load based on I-O tables from the 1990 edition to the 1995 edition, LC-CO2 at
the operation and maintenance stage in the life-cycle for the four treatment plants increased approximately 3–5% and
LCE decreased approximately 5–7%. As a result, LC-CO2 and LCE derived from electricity consumption increased 5.8%
and decreased 6.2%, respectively, so it is inferred that the environmental load derived from the consumption of chemicals(coagulant, sodium hypochlorite, etc.) and fuel (oil, gas, etc.) had little influence on the total environmental load.
Except for particular plants which use large quantities of chemicals and fuel, it is assumed that the updating of the
primary unit load based on I-O tables from the 1990 edition to the 1995 edition has little influence on the environmentalload for wastewater treatment plant at the operation and maintenance stage in the life-cycle.
This research examined the application of LCA to wastewater systems as a project evaluation method at the planningand design stage of projects. The results will be used to promote wastewater projects appropriately from the perspectiveof global environmental protection.

14

EVALUATION METHOD FOR ADVANCED WASTEWATER TREATMENT SYSTEMS
M. Minamiyama, Y. Aratani, H. Yamagata
Wastewater and Sludge Management Division
Project period: 2002-2004
Objective
The water quality in enclosed water bodies must be improved, and advanced wastewater treatment is one effectivemeans. Part of the cost for advanced treatment is to be collected from sewerage fees in accordance with thepolluter-pays principle. Thus, ways of explaining to people the need for advanced treatment through discussions
based on scientific information including the cost and benefit of advanced treatment, are required. Therefore, in
cooperation with an NPO that is involved in preserving the water of Lake Biwa and sewerage systems, wedeveloped a method of evaluating advanced treatment from the view of people .
Method and Results
In this study, we developed a method for obtaining an understanding of advanced wastewater treatment by
increasing the knowledge of people concerning the water environment using newsletters and questionnaires(Figure.1) .

≪Administration ≫≪NPO≫≪People≫evaluation andidentification of needs

conveying the needs

Newsletter 1
Expertinformation

1st questionnaire

providing information 1

Comparison

conveyingexpert information
evaluation andidentification of needs

2nd questionnaire

conveying the needs

Newsletter 2
conveyingexpert information

providing information 2

Comparison

3rd questionnaire

Figure 1 Survey of change in people awareness by providing information in collaboration with NPO

15

The results were as follows.
(1) To increase the knowledge of people concerning the water environment, we developed the new process that an
NPO as a neutral position between the administration and people, identified the information needed by people,
obtained expert information from the administration, and conveyed it to the people in a simple newsletter.
(2) Conveying information to the people twice by newsletters has increased their knowledge concerning water
environment problems and measures. For example, the number of people who understand that agriculture
wastewater and road wastewater other than domestic wastewater are sources of pollution of Lake Biwa has
increased; the number of people who are aware of the dioxin and endocrine disrupter other than the red tide as anenvironmental problem of Lake Biwa has increased; the number of people who understand the need to adopt theadvanced wastewater treatment and urban rain wastewater treatment to protect the environment of Lake Biwa has
increased; and the number of people who recognize various effects such as further removal of nitrogen/phosphor
and removal of trihalomethane formation potential and endocrine disrupters by adopting ultra-advanced wastewater
treatment has increased.
(3) After information was provided for the first time, the number of people willing to pay for the preservation of thewater environment of Lake Biwa increased. The willingness to pay for ultra-advanced wastewater treatment was
189 yen per month/household, which was relatively higher than its maintenance expenses of about 160 yen permonth/household.. However, 30% of people were not willing to pay anything, so there is a need to reduce this ratio.

16

RESEARCH ON THE STANDARDS FOR HYGEINIC SADETY OF THE TREATEDWASTEWATER
A. Tajima, K. Sakurai and M. Minamiyama
Wastewater and Sludge Management Division, Water Quality Control Department
Project period: 2001-2005

OBJECTIVES
It is expected that reuse of treated wastewater will increase in the future from the viewpoint of saving water resources inurban areas, which will in turn increase the importance of appropriately reusing treated wastewater.
On the other hand, the health risk posed by Cryptosporidium and other pathogenic microbes through drinking water andfood has become a severe social problem in recent years, raising concerns over the safety of water. It is, therefore,
necessary that the reuse of treated wastewater employ countermeasures against these new problems from now on.
For the above reasons, the Sewerage and Wastewater Management Department of the Ministry of Land, Infrastructure
and Transport and the Water Quality Control Department of the National Institute for Land and InfrastructureManagement decided to revise the water quality standards and the water quality targets stipulated in the previous
guidelines and manuals for the reuse of treated wastewater. And, in order to establish new standards from the perspectiveof guaranteeing hygienic safety, these organizations have carried out fact-finding surveys on bacteria and protozoa in thereuse of treated wastewater. This report presents the results of the fact-finding surveys and the results of studies on new
standards based on these surveys.

MATERIALS AND METHODS(1) In order to study standards forbacteria

in

the

reuse

of

treatedwastewater, the pathogenic microbes
and related indices shown in Table 1
were measured throughout a one-year

Category

Items analyzed

General items

pH, water temperature, turbidity, SS, residual
chlorine (free, combined)

Bacteria

Index

E. coliperiod in the treated wastewater reuse

Heterotrophic plate counts (HPC)*

systems that use the five reclamation
treatment processes at four WTPs in
Japan.

Total coliforms

Pathogenic

Legionellabacteria

Salmonella, Campylobacter, EHEC O-157

The measured pathogenic bacteria were Salmonella and Campylobacter that are major causes of food poisoning in Japan,
EHEC O-157 that caused a severe outbreak of group infections in Japan, and Legionella that can propagate in thereclaimed water supply process.
Samples were obtained at three locations – water overflowing from the final settling tank, immediately after thereclamation treatment process, and in the tank receiving supplied water.
(2) In order to study standards for protozoa in the reuse of treated wastewater, sand-filtered water from two WTPs in
Japan were surveyed for Cryptosporidium every month for two years and then evaluated the risk of Cryptosporidium inthe reuse of treated wastewater based on the results of the survey to study treatment standards capable of ensuring an

17

appropriate risk level.

RESULTS(1) There were cases where total coliforms propagated in the supply tank, but there were almost no cases where E. coli
propagated in the supply tank. Because it is assumed that when a certain period of time has passed after reclamation
treatment, it is considered inappropriate to use bacteria that have propagated in the water environment as index bacteria,suggesting that E. coli would be more appropriate than total coliforms as the index bacteria in the reuse of treatedwastewater.
(2) The fact that it is possible to lower HPC to a specified level by maintaining the combined residual chlorine
concentration at 0.3 mg/L or more suggests that a standard value of 0.3 mg/L or more is necessary for the combined
residual chlorine concentration. On the other hand, target pathogenic bacteria were not detected in any samples.
(3) When it is assumed that toilet flushing water, sprinkling water, and landscaping water are produced by sand filtration,and recreational water is produced by coagulation treatment and sand filtration, the annual Cryptosporidium infection
risk is about 10-4 or less for the reuse of treated wastewater at normal times, suggesting that it is possible to satisfy thetarget infection risk advocated by the USEPA.
2001-2002
2002
2001

Toilet flushing water (Office)*1

Toilet flushing water (Office)*2

Sprinklng water (Park)*1

Sprinkling water (grass)*2

Landscaping water (Park)*1

Landscaping water (fishing)*2

Recreational water (Park)*1
Recreational water(swimming)*2
Recreational water (contact byhands)*2
Recreational water (waterfalls
and foutains in large scale)*2

1.0E-1010-10

1.0E-0810-8-61.0E-06
1.0E-0410
10-4
年間感染リスク
Annualinfection risk

1.0E-0210-2

Note: The infection risk for recreational water assumes treatment by coagulation treatment and sand filtration, and for otheruses, it assums sand filtration.
Note: *1：Table 6 is applied. *2：Table 7 is applied

18

FATE OF SANITARY INDICATORS IN TREATED WASTEWATER
Mizuhiko Minamiyama, Ryosuke Hiraide, Kensuke Sakurai
Wastewater and Sludge Management Division
Project period: 2002-2004

OBJECTIVESThe spread of wastewater treatment systems has raised the quantities of treated wastewater discharged by wastewater treatment
plants, increasing the percentage of treated wastewater in river water. And the treated wastewater is reused in a variety of ways inurban regions. This means an increase in opportunities for people to come into direct contact with treated wastewater.
However, treated wastewater contains a variety of pathogenic microorganisms produced by human activities. Traditionally, total
coliforms have been used to indicate the existence of pathogenic microorganisms, but they are not adequately reliable as an index.
In order to appropriately maintain the hygienic safety of treated wastewater and environmental water, the properties of various
kinds of indicator microorganisms should be clarified to select an index appropriate to each purpose. This study was a survey
conducted to compare the behavior of total coliforms that have been used in the past, E.coli, faecal streptococcus, andC.Perfringens spores in receiving waters to clarify the properties of indicator microorganisms.

METHOD and RESULTS
From FY2002 to FY2004, research was carried out in order to clarify the behavior of various kinds of indicator microorganisms
after the discharge of treated wastewater. The results have revealed that total coliforms that have been used as an index of faecal
pollution in the past do play a certain role as an index that clarifies disinfection effects on treated wastewater. However, underconditions such as its use as an index of hygienic safety after a certain degree of time has passed since it is discharged, whentreated wastewater is reused for example, there are cases where it cannot necessarily be described as a an appropriate index
because total coliforms increases during a short period of time, even in the same water. There are cases where it would be better
to use E.coli that measured by a specific enzyme substrate culture that did not increase or decrease very much even after chlorine
disinfection during this testing as the index. It would be difficult to use faecal streptococcus that has a low absolute count as anindicator microorganism. It can be concluded that C.Perfringens spores show strong chlorine resistance, because their count did
not change even when the degree of chlorine disinfection was varied, so they can be used as an indicator of pathogenic
microorganisms that are chlorine resistant. But, the fact that C.Perfringens spores appeared to have stronger settleability thanE.coli etc., has suggested that it would be difficult to make a judgment that there are no pollutants by pathogenic microorganisms
simply because C.Perfringens spores are not detected.

19

EFFICIENT REMOVAL OF SLIGHT HAZARDOUS MATERIALS BY OZONATION
T. Hirayama and M. Minamiyama
Wastewater and Sludge Management Division, Water Quality Control Department
Project period: 2002-2004

OBJECTIVES
The problems of the slight hazardous materials represented by the endocrine disruptors are getting more serious year by year.
These materials may have a bad influence on natural environment, ecosystem and human health even if these are slightly
contained. Endocrine disruptor is said to decrease sharply in process of wastewater treatment by some researches, but the
influence which endocrine disruptor have on ecosystem is unknown and it may be needed to decrease more on the basis of theinfluence. The objectives of this research is to establish the way of efficient removal of slight hazardous materials by
ozonation.

RESULTSWe decided nonylphenol (below written, “NP”), bisphenol-A (below written, “BPA”), 17β-estradiol (below written, “E2”)and estorone (below written, “E1”) as the target substances. In order to clarify ozonation operating conditions that effectively
remove the target substances from treated wastewater, and influences that the treated wastewater qualities have on removing
the target substances by ozonation, pilot plant experiments were carried out. The results are as follows.
(1) When the ozone contact times were from 3 to 15min and the reactor height is 1.6m or 4.1m, BPA was reduced to below
the detection limit at an ozone injection rate of 5mg-O3/L, NP and E2 were reduced to below the detection limit at ozone
injection rates of 3mg-O3/L or higher, E1 was reduced to below the quantitative limit at an ozone injection rate of
5mg-O3/L.
(2) When an ozone injection rate was 1.5mg-O3/L, there were several cases where NP, BPA and E2 were not reduced to
below the detection limit, E1 was not reduced to below the quantitative limit. There was no correlation between the ozone
contact times and the removal rates of the target substances at an ozone injection rate of 1.5mg-O3/L, when the ozone
contact times were from 3 to 15min.
(3) When an ozone injection rate was 1.5mg-O3/L and E260(the absorbance of ultraviolet rays of 260nm-wavelength), whichis the index of organic materials which have unsaturated combinations, was less than 0.09, NP, BPA and E2 were reduced
to below the detection limit, E1 was reduced to below the quantitative limit. It is expected that E260 could be used as theindex of materials which are more easily oxidized by ozonation than the target substances, and that we could find an
effective ozone injection rate by using E260.

20

Study on Wastewater Reclamation System for the River Ecosystem
M. Minamiyama, Y. Aratani and R. Hiraide
Wastewater and Sludge Management Division
Project period: FY2001-2005

OBJECTIVESAs the amount of treated wastewater is increasing in response to the coverage of sewerage systems, there is a growing
tendency to utilize treated wastewater to create water environments. Treated wastewater is sometimes extensively utilized tocreate streams and other water environments in urban areas that have disappeared due to urbanization. Streams and other water
environments are valuable spaces not only for human lives but also as habitats for all kinds of aquatic lives. However, therelationship between aquatic lives that inhabit these water environments and the quality of treated wastewater is not clearly
understood. Because treated wastewater is a valuable water resource, it is important to evaluate wastewater treatment systems
from the perspective of habitat environments in the receiving water bodies of treated wastewater. Tadotsu town in Kagawa
prefecture tries to utilize treated wastewater as reclaimed wastewater in an artificial stream as a receiving water body. This
stream was first operated using drinking water, but now reclaimed wastewater is used. This study was carried out to clarify theeffects of the water qualities of reclaimed wastewater and drinking water such as nutrients on periphytic algae grown in theartificial stream in the town.

METHODIn the artificial stream in Tadotsu town, Kagawa prefecture, two types of field survey were carried out, one for the effects ofdrinking water and the other for the effects of reclaimed wastewater on aquatic life. The surveys for drinking water werecarried out two times from January and March 2004, and for reclaimed wastewater two times from September andNovember 2004 and from January and March 2005. To compare the effects of the two types of water, periphytic algae andwater qualities were analyzed. Unglazed ceramic plates were installed in the upper reaches to analyze periphytic algae, andthe biomass (cell count), the community composition and the diversity of periphytic algae were analyzed.

RESULTS(1) Biomass
The concentration of nitrogen of reclaimed wastewater was ten times as high as that of drinking water. On the other hand,the concentration of phosphorus of reclaimed wastewater and drinking water was the same level. It is supposed that there were
no differences between the biomass for drinking water and reclaimed wastewater because of the same concentration level ofphosphorus.
(2) Community composition
In the survey of reclaimed wastewater from September and November 2004, Homoeothrix janthina of Cyanophyceae wasdominant, which is a representative species in relatively clean rivers in Japan.
Bacillariophyceae and Cyanophyceae were dominant and there were no differences between drinking water and reclaimed
wastewater in the number of cells by taxonomic class in the same survey period from January and March.
(3) Diversity
The number of species was at the same level between the survey of drinking water and that of reclaimed wastewater.

21

RESEARCH ON THE RISK ASSESSMENT OF CHEMICAL SUBSTANCESIN A WATER ENVIRONMENT
M. Takahashi, T. Shimizu, M. Minamiyama, H. Yamagata
Wastewater and Sludge Management Division
Project period: 2003-2005

Objective
The influence of chemical substances such as endocrine disrupters on human beings and the ecosystem
has become a serious social problem, and there has been a growing interest in chemical substances.
The Ministry of Land Infrastructure and Transport is in charge of managing the risks of chemical
substances in the environment in cooperation with local organizations in charge of managing rivers, seweragesystems, roads and the like. However, it is not easy to grasp which substances have a high risk in the target basins,
and which substances should be the object of priority studies, because there are many kinds of chemical substances.
Nevertheless, the results of PRTR studies have been compiled and published since fiscal 2002, showing the current
state of discharge of chemical substances in the target basins. This study aimed to grasp the amount of chemical
substances discharged into river basins and the behavior in the water environment based on PRTR information; toperform a risk assessment based on the current state; to share the results with stakeholders related to the areas; andto establish a risk management method for the basins.
Start
Target ofThis Paper

Risk Information for Chemical Substances

Collection of PRTR Information
on Sources of Chemical Substances
Collection of Basic Basin
Information ( size, population, land use etc.)
Selection of Chemical Substances
for Risk Assessment

Survey of Chemical Substances
in Water Environment
Behavioral Model for Chemical Substances

Identification of Discharge Sourcesand Grasp of Behavior of
Selected Chemical Substances

Convert Basin Information into GIS andEstablish Hydrology/ Water Quality Model

Identification of stakeholders
Communication on Chemical Riskwith Stakeholders

Planning of Countermeasures
to Reduce Chemical Risk
End

Figure 1 Scheme of Comprehensive Management of Chemical Risk and Target of This Research

22Method and Results
In fiscal 2004 the study covered the following.
1) Regarding the target chemical substances (zinc, lead, arsenic, manganese, nickel, copper, chrome, fluorine,boron,

polyoxyethylene

nonionic

surface-active

agents,17 β -estradiol,

estrone,nonylphenol,

nonylphenolethoxylate, nonyl phenoxyacetic acid) which were detected in the model rivers in fiscal 2003, theconcentration in the rivers including water, suspended substances, and bottom sediments was surveyed, andthe concentration was evaluated in terms of human health and protection of aquatic ecosystem based on
domestic and overseas information. In the model rivers, zinc was identified as being a priority for risk
management in order to protect aquatic ecosystem.
2) Based on research on the status of the target chemical substances in the influent and effluent of seweragetreatment plants in the model area in order to identify the discharge sources of the detected target chemical
substances, the contribution in the sewerage effluent water of estrone and boron was higher than that of
CODcr and SS, but the contribution with respect to the other chemical substances was low. Nonylphenol
ethoxylate, nonylphenol, and polyoxyethylene nonionic surface-active agents were effectively removed by thesewerage treatment plants.
3) The businesses which must report their discharge amount of target chemical substances by PRTR law (socalled “designated businesses”) in the basins of the model river were grasped, and the contributions of theloads of target chemical substances in the model rivers were evaluated. The results suggested that it isdifficult to evaluate the concentrations of target chemical substances in rivers receiving effluent when using
only the annual loads reported from the designated businesses. This could be because the concentration of thetarget chemical substances in the effluent water from the designated businesses has a large daily and seasonalvariation in accordance with the operational situation, etc.; that the flow of the river has daily and seasonalvariations; and that there is a contribution from the businesses which do not have to report their discharge
amount of target chemical substances and other discharge sources such as domestic wastewater, agricultural
wastewater, etc.

23

Sustainable water policy scenarios for river basins with rapidly in creasing population- Countermeasure strategy to global hydrological variation in monsoon Asia EVALUATION OF WATER QUALITY SECURITY MEASURESIN THE GANGES RIVER BASIN
M. Minamiyama, R. Hiraide, K. Sakurai

Wastewater and Sludge Management Division
Project period: FY2003-2008

OBJECTIVESIn Asia and other regions, rapid population growth, urban development, and industrialization haveexacerbated water problems, and human activities have caused fluctuation of water cycles and other problems.
The goal of this research is to help resolve these problems by presenting policy scenarios for nine typical Asianriver systems. This research is done as team research (CREST type) led by research representative Professor
Sunada of the University of Yamanashi, because the area studied is vast and faces many challenges. The
Wastewater and Sludge Management Division of the NILIM is in charge of the presentation of policy scenarioswith priority on water problems in the Ganges river basin.

OBJECT AREAThe Ganges River is the most heavily populated river basin
in Asia, and here, population growth and urbanization have beenaccompanied by water quality pollution and the consequent
shortage of sanitary water, flooding, and other serious problems.
Asian rivers typified by the Ganges River are irreplaceable for

Ｋolkata

the daily life of the people, many of whom use them for bathing
and washing clothes, and who discharge their human waste intheir waters. These results in rampant infectious diseases
originating in the river water, and in regions where urbanization

Figure 1 Ganges river area

is particularly advanced, water pollution accompanied by healthproblems caused by pathogenic microorganisms are serious public issues. Therefore, water quality preservation
measures have been proposed as ways to prevent health problems caused by pathogenic microorganisms,
taking the Ganges River Basin as the major example.

METHOD
This research is carried out by first conducting a field survey to collect adequate basic documents
concerning the life style of the local people, state of pollution of the river, pollution sources and basic units,24

then based on these findings, organizing step-by-step sewerage system provision methods that hypothesize
future developments to present scenarios with the priority on water quality problems. The field survey is asurvey centered on the Indian capitol city of New Delhi where water pollution is particularly severe. The
Yamuna River is a tributary of the Ganges river in New Delhi. The survey included observations of the region
and measurements of water quality in New Delhi and its surroundings.

RESULT
The pollutant load per unit activity of source was calculated based on the results of a field survey. Amonghigh income, middle income, and low income districts in the city, the SS load was high in the high income
districts, but the values in other districts were equal those values in Japan. A high discharge per unit production
was predicted in slums because it was only toilet wastewater, but values other than T-N were low and it was
assumed that the septic tanks function adequately.
In local villages, all loads were extremely low values. It is assumed that the quantity of water used is low
because it is not supplied by a public water supply system, but is manually pumped up ground water.
Regarding other loads, assuming that people do not stay in their houses during the day when they are
performing agriculture work and that there is a strong tendency for people to excrete outdoors relatively often
when performing agricultural work, there is a discharge load that is not counted.
Because there are differences between Japan and three types of domestic animals in Gazipur, Bhalsawa,
and Madanpur and the feed, rearing environment, and types of cattle (cattle and water buffalo) also differ, anequivalent discrepancy appeared. The number of cattle barns in suburbs is now soaring as a result of theconcentration of the population in cities, and it is predicted that demand will increase in the future, so it isassumed that cattle barn excreta will also increase. They must, therefore, be surveyed in detail as large sourcesof discharge.
Table 1 pollutant load per unit activity of source
water volume
L/person/day
wastewater in Japanhigh income in the city

Jor BaghPachkuian Road
middle income in the city
Paharganj
Shalimar Baghwastewater low income in the city
in Indiaslum, night soil only
VikaspuriPallalocal village
Latpur Chatera
Mujeribarn wastewater in Japan
Ghazipurdairy farm wastewater in India
Bhalsawa
MadanpurBODg/person/day
140
216
73
108
27
47
17
37
123
71
97

CODcr
SS
T-N
T-P
g/person/day
g/person/day
g/person/day
g/person/day
58
27 (Mn)
45
11
27
50
122
9
24
42
10
11
37
47
4
6
26
69
39
10
3
11
2
16
5
8
3
3
4
6
4
2
9
21
8
3
640
530 (Mn)
3000
290
183
878
59
60
875
1849
1536
84
875
1529
1099
119

coliform group
MPN/person/day
1
2
1
1
4
1
1
1
1
50
5
9
13

6.2×1010
5.2×1010
1.7×1010
6.2×1005
4.5×1008
1.2×1010
6.5×1003
1.7×1006
1.3×1012
3.3×1005
1.6×1005

Support: JAPAN SCIENCE AND TECHNOLOGY AGENCY (JST) CREST

25

RESEARCH ON THE INFLUENCE OF SOIL AND GROUNDWATER CONTAMINATIONTO SURFACE WATER
M.Minamiyama, H. Yamagata
Wastewater and Sludge Management Division
Project period: 2004-2005

Objective
Groundwater contamination by volatile organic compounds (VOC), heavy metals, nitrate nitrogen, etc. has
become a problem. In fiscal 2002, the Soil Contamination Countermeasures Law came into force. However, theinfluence of chemical substances from ground water to surface water remain unclear.
Therefore, this study selected chemical substances to be surveyed from the view of the influence from groundwater to surface water, and then surveyed the behavior of these chemical substances in ground water.
Method and Results
1) Selection of substances to be surveyed
Chemical substances that could affect water bodies via ground water were selected to be surveyed in this study
from the following points of view.
(1) Chemical substances designated in the Soil Contamination Countermeasures Law
In the Soil Contamination Countermeasures Law, the elution amount standard is provided for class-1 specified
harmful substances (VOC 11 substances), class-2 specified harmful substance (nine substances such as heavy
metals), and class-3 specified harmful substances (five substances such as agricultural chemicals) in accordancewith the Environmental Quality Standard Items relating to soil contamination, in terms of their influence onhuman health through ingestion in contaminated ground water, etc. These substances were selected as survey
targets.
(2) Nitrate nitrogen and ammonia nitrogen
Nitrate nitrogen and ammonia nitrogen were specified to be Environmental Quality Standard Items relating towater contamination of ground water in 1998 due to their influence on human health. In this study, nitrate
nitrogen is included as a survey target. Ammonia nitride, which is contained in waste from humans and animals,
was included as a survey target because it is nitrified.
(3) Environmental Quality Standard Substances concerning preservation of aquatic organisms
Total zinc was specified as an Environmental Quality Standard Item concerning preservation of aquatic
ecosystem in 2003. Total zinc was included as a survey target because it contaminates water bodies from groundwater.
(4) Higher-ranked substances in the PRTR which are discharged in large quantities to soil or disposed of in landfills
on businessAccording to the PRTR, the substance that was discharged into the soil on business premises in the largest
amounts was ethylene glycol, so ethylene glycol was included as a survey target.
(5) Others
Among the six substances which were specified as targets of the Environmental Survey for Exposure Study infiscal 2002 by the Ministry of the Environment, perfluoro octane sulfuric acid (PFOS), has extremely highrepeated-dose toxicity, and is considered to have high acute toxicity to aquatic organisms, so PFOS was included
as a survey target.
Hydrazine and polyoxyethylene alkyl ether (C=12–15) and D-D (1,3 dichloropropene) were included assurvey targets, because the amounts used and discharged are estimated to be comparatively large based on
surveys held by Graduate School of Yokohama National University.

262) Survey of Abundance of Chemical Substances in Ground Water
The Nagata area in the middle reaches of the Tama river of Tokyo(Fig.1) and the Yata river basin in Ibaragi
prefecture(Fig.2) were selected as survey target areas because ground water has influenced their waters.

River water

Groundwater in riverbed

Groundwater in riverbed

Spring water ofKusabana Hill

Sampling points

Figure 1 Nagata Area of Tama River(1) Undetected substances in all or most of the areas
Cadmium and its compounds, PCB, carbon tetrachloride,standard agricultural chemicals (thiuram, simazine, thiobencarb,River
organic phosphorous compounds), and D-D were not detected in
Border of Basinany of the areas.
Developed Area
As for VOC, dichloromethane and trichloroethylene were not
New Railway
Planned Highway
detected or detected slightly in the Tama river, spring water from
Kusabana hill, and ground water of the Yata river basin.
Surveyed Well
(2) Substances detected in all the areas
The substances which were detected in all the areas were
ethylene glycol, total zinc, nitrate nitrogen, ammonia nitrogen,hydrazine, and PFOS. Manganese and its compounds, total
chromium, selenium and boron were not detected or detectedslightly.
As for nitrate nitrogen, concentration was more than the levelof the ground water environmental quality standard value (10mg/1) in W2 and W3 (both are fields), and W9 (lawn grass) of
the Yata river basin in Ibaragi prefecture, presumably due to the
Figure 2 Yata river basin (Ibaraki)
application of fertilizer. Nitrate nitrogen was found at a low
concentration in W9 (paddy field), which was considered to be caused by the application of a small quantity offertilizer. Nitrate nitrogen concentration was larger in SP7 (spring water of Kusabana hill) of the Nagata thanin G6 and G7 (underflow water in riverbed of the Tama river), so the contribution of nitrate nitrogen derived
from the application of fertilizers on farmland, golf courses, etc. in the Kusabana hill was considered to belarge.
As for total zinc, substantially constant concentrations (0.01 to 0.02 mg/1) were detected in both of groundwater and river water.
As for hydrazine, it was detected in the river water of the Tama river, W2 and W3 (both are fields), and W9(lawn grass) in the Yata river basin in Ibaragi prefecture.
As for PFOS, about 0.0005 μg/l was detected in the ground water and the river water in the Nagata area, andabout 0.0002 μg/l in the Yata river basin. PFOS in the spring water of Kusabana hill of the Nagata area wasfound in a higher concentration by one order (0.0024 μg/l). From the survey of PFOS in the Tama river, PFOS
concentration was reported to be 0022 μg/l upstream from the sewerage treatment plant, which was close to thevalue observed in the Nagata area and the Yata river basin.

27