This study analyzed samples from 258 groundwater sources in Jordan to establish baseline levels of the gasoline additive MTBE and petroleum derivatives BTEX. The study aimed to investigate potential contamination and inform monitoring programs. Most samples showed MTBE and BTEX levels below standards. However, two wells near gas stations exhibited temporary MTBE contamination, indicating vulnerability. The study recommends continuous monitoring, soil sampling near fuel tanks, and gas station regulations to prevent pollution of this vital water resource. The two-year study was funded by the Scientific Research Fund and informed the need for ongoing assessment of Jordan's water resources.

1. BASELINE DETERMINATION OF GASOLINE ADDITIVE METHYL TERTIARY
BUTYL ETHER (MTBE) AND PETROLEUM DERIVATIVES (BTEX) IN WATER
RESOURCES
Prepared by
Randa Tuffaha
Water authority of Jordan
E-mail: randa_tuffaha@mwi.gov.jo
randatuffaha@yahoo.com

2. Outline
• Introduction
• Aims of the project
• Methodology
• Results and Discussions
• Recommendations

3. Introduction/project
• The intense search for effective and economical octane boosting alternative to
lead as a gasoline additive has continued since the past decades.
• Oxygenates have emerged as alternatives for improving the octane number and
the oxygen content in gasoline.
• The most important of these oxygenates has been methyl tertiary butyl ether
(MTBE) added to gasoline to help reduce air pollution (Hamdan and Al-Subaih,
2002).
• The use of unleaded benzene in Jordan has required the addition of MTBE to
gasoline.
• Due to the in availability of data of the levels of MTBE in ground basins, a proposal
has been delivered to the Scientific Research Support
• The proposal has been approved and financed for study period of 2 years

4. What This Study Aims to?
• Investigate possible occurrence, distribution, and
sources of MTBE and gasoline components of
benzene, toluene, ethyl benzene and xylenes
(BTEX) group in Jordan’s water resources through
a preliminary assessment study.
• No other studies so far have addressed the issue
of MTBE and BTEX contamination in Jordan’s
water.
• There are no standards for MTBE in public water
supplies in Jordan.

5. Chemical Structure & Properties of
MTBE
Properties
 It has relatively high
solubility in water.
 Low soil adsorption.
 It is slowly biodegraded.
 It has the potential for
persistent contamination of
ground water in case of its
release to environment
through spills, leaking of
storage tanks, or other
pathways .

6. BTEX
BTEX is an acronym that stands for
benzene, toluene, ethyl benzene and
xylenes. These compounds are volatile
organic compounds (VOCs) found in
petroleum derivatives such as gasoline

7. Methodology
• Study area
• Sampling locations
• Field trips
• Analytical works

8. Study Area
• The study area is located in the
north of Jordan and extended
from Amman city to the north
reaching Irbid city.
• The average annual rainfall varies
from less than 150 mm southeast
to more than 600mm Northwest
• The area is highly developed and
there is a continuous and
increasing demand for water to
meet the industrial, irrigation and
domestic requirements.
Location Map of the Study
Area

9. Study Area
• The Amman-Zarqa Basin is one of Jordan’s biggest
groundwater basins.
• Almost half of the population of Jordan lives in the
big cities of Amman, Zarqa.
• The domestic water supply is based entirely on
groundwater.

10. Geology and Structure

11. Hydrogeology
According to the potentiality of water bearing, three
aquifer systems are available in in the study area:
• Upper aquifer system, which includes Basalt and
underlying Amman-Wadi As Sir (B2/A7) formation.
 Middle aquifer system, consisting of Hummar (A4)
and Naur (A1/2) formations.
 Lower aquifer system (Kurnub Group).

12. Vulnerability of the Study Area
Wells in Amman-Zarqa basin locate mostly within low
vulnerability class to moderate class.

13. Gas Stations
Information on Gas Stations
• There are 276 gas stations
distributed over the study area.
• All tanks in gas stations are
owned either by JPR or private
sector.
• They are of single walled and the
ages of these tanks ranged
between (1-40) years for tanks
owned by the JPR.
• The ages of the tanks owned by
private sector are (1-13) years,
which represent 45% of total
gasoline tanks.
Location of gas stations in the
study areas

14. Sites Selection Justification
• Locations of wells and springs
nearby gas stations within less
than 1 km approximately.
• Most of gas stations in selected
area are old design and there is
absence of monitoring on storage
tanks.
• Presence of car services stations
around inside protection zone 2
for water resources.
• Geological characteristics for
wells and springs location, which
are mainly described as recharge
area and have direct connecting
to aquifer especially in Zarqa river
watershed.

15. Sampling Locations
• Most of sampling locations
of wells were distributed in
the three aquifer types,
most of them locate in the
upper aquifer ( B2/A7) ,
which is considered a vital
basin to supply water and
vulnerable to pollution.
Other sampling locations
wells locates in middle and
lower aquifers, which they
spread mostly in side wadis
and some northern areas

16. .
sampling locations of the study area
within 1 Km of the gas stations

17. Ambient sampling locations and
MTBE sampling locations
• The MTBE concentrations
near release sites are
compared to MTBE
concentrations in ambient
ground water (ground water
that is not thought to be
associated with point-
source releases of MTBE or
BTEX compounds).

18. Field trip
• Sample locations were specified using Geographic
Information System (GIS) maps and Geographic
Positioning System (GPS) tools.
• Field work was carried out in winter and summer
seasons to observe the seasonal variation effect
on the levels of MTBE and BTEX.
• It consisted of field measurements and collection
of 258 groundwater samples.
Sampling Campaign

19. Analytical Techniques
• Purge and Trap Concentrator-Gas
ChromatographPu-Mass Spectrometer
• Purge and Trap Concentrator-Gas
Chromatograph-Flame Ionization
DetectorTechnique (P&T –GC-FID) was used to
analyze MTBE and BTEX compounds.

20. Results of field Parameters
Amman-Zarqa Basin
• pH of all monitored wells was neutral and
ranged from 6.86 to 7.72.
• Dissolved oxygen ranged from 2.87 to 14.4
mg/l,High Levels of DO at Hashimiyya
Wells (3),(5) were observed at 12.4, 13.5
mg/l respectively. This increase may be
due to water table condition, where the
static water level is close to surface (47m).
• Turbidity ranged from 0.30 to 43.5 NTU,
Baqa'a well 2 showed high turbidity of
43.5 NTU, this is may be due to pumping
rate higher than capacity of aquifer, so the
turbulent flow increasing the turbidity,
and may caving between casing and well
wall so it affected to increasing the
Turbidity.

21. Results of field Parameters
Amman-Zarqa Basin
• Electrical conductivity ranged
from 510 to 3910µs/cm.
Hashimiyya Wells (3),(5) and
Zarqa well 3 showed high
dissolved solids content, this
increase is due to over
abstraction, Geochemical
factors, which caused increase
of EC of some wells during the
last 20 years.
• Temperature ranged from 17
to 270C.

22. Results of field Parameters
Northern
Governorate/Yarmouk Basin
• pH of all monitored wells
was neutral and ranged
from 6.8 to 8.16.
• Dissolved oxygen ranged
from 1.85 to 9.11 mg/l.
• Turbidity ranged from 0.45
to 2.26 NTU

23. Results of field Parameters
Northern Governorate/Yarmouk
Basin
• Electrical conductivity ranged
from 510 to 7380µs/cm,
where Safawi well and
kuraymma 4 well showed high
EC at 7380, 4630 µs/cm
respectively.
• Temperature ranged from 12
to 560C, where the
temperature of North Shoneh
well was 560C, this is due to
geothermal reasons as the
well is a very deep well around
(967m).

24. Results and Discussions
• The upper aquifer is
characterized by highly
fractured and unconsolidated
materials, this will contribute
to the seepage of MTBE in
case of leakage.
• A sign of contamination was
observed in Hashimeya wells
no 2 and 5, with a MTBE
concentrations of 32.6 and
17.9 µg/l in summer season.

25. Explanation of Significant Decrease in
Detected MTBE Wells
• The results of Hashimeya wells no 2 and 5
showed no sign of contamination in winter and
all of the analysed samples were below LRV (<
1µg/l).
• It might be an accidental release from oil tanker
or the result of a deliberate leak into water wells
through the fractured and unconsolidated aquifer
(B2/A7).
• The significant decrease in winter season is due
to the rainfall and dilution of the contamination
and flushing the polluted pulse.

26. Results and Discussions
• The middle aquifer showed for most wells a level < 1µg/l and
complied with smell and taste threshold US EPA Guidelines and
followed the National and International Guidelines for BTEX.
• These results correlated with the low rainfall rate and the
possibility to transfer of pollutants into the aquifer depending on
the thickness of aquifer layers and wells depth, where the deep
wells are less subjected to contamination in comparison with
shallow wells.
• It is characterized by a protective layers from the above
formations, which is high clay content acting as impervious layers.
• The depth of the groundwater is more than 100 m which means a
very long pathway for the contaminant to reach the aquifer.

27. Results and Discussions
• The lower aquifer showed for wells a level <
1µg/l and complied with smell and taste
threshold US EPA Guidelines and followed the
National and International Guidelines for
BTEX.
• It is very deep and almost protected from any
contamination.

28. Results and Discussions
• The analytical results of MTBE have revealed that
concentrations of most monitored wells in Amman-Zarqa
basin and Northern Governorate were not detectable and
below the LRV (<1 µg/l) and comply with the national and
international standards.
• In theory these results should positively correlate with the
rainfall rate and negatively with the sampling depth/well
depth, which means deep wells should be less subjected to
contamination than shallow wells.
• The transfer of these compound takes longer even though
the solubility of MTBE in water is high and it is quickly
moving in groundwater for long distances in comparison
with BTEX compounds

29. Conclusions
This study covered water resources vulnerability
due to MTBE and BTEX pollution in Amman-
Zarqa Basin and Northern Governorate. The
investigation considered the variation levels
on the long term, the depth of wells and type
of aquifers.
This study is a first step in establishing a
monitoring program for these substances in
Jordan.

30. Conclusions
• This study covered 131 ground water
resources which included 258 water samples
during winter and summer season.
• The results of MTBE was below LRV (< 1µg/l)
for most monitored sources and BTEX
detection comply with the National and
International guidelines.
• There is no contamination from MTBE and
BTEX in the investigated

31. Recommendations
 Continuous monitoring of MTBE and BTEX to
water resources is important.
 Monitoring the levels of MTBE and BTEX in
soil samples underneath the fuel tanks in
certain critical sites.
 Development of specifications for gas stations
to maintain the integrity of the sustainability
of the quality of these sources and to prevent
the arrival of any pollutants in the future.

32. Financial Body: Scientific Research fund
Duration of the Study: 2 Years
Researchers:
Eng. Randa Tuffaha Dr. Mustafa Al-Kaisi
Bio. Refaat Bani-Khalaf Eng. Maher Hreishat
Chem. Lama Saleh Saleh Abu-Alhaija

33. Acknowledgements
We wish to acknowledge the Scientific
Research Fund for their financial
support to fund this work.
Appreciation is due to Water Authority
of Jordan for their technical and
administrative support to apply this
study.

34. Thank You for Your Attention