Technical Manual for Drilling Works for Technical Support Plan for the Drillers in DDCA (2013)

DDCAP Technical Manual for Tool Fishing and Well Rehabilitation

For Technical Support Plan for the Drillers in DDCA

12.2 FISHING TOOLS (TA CODE 12-2)

There are many types of fishing tools as shown in Figure 3 and Figure 4. These tools are

selected depending on the purpose of each stage of tool fishing works.

Each fishing tool is manufacture for certain range of dimension of fallen materials. It is not

possible to keep stock of fishing tools for all types and dimensions of fallen materials.

Therefore, the skills for manufacturing “order-made” fishing tools to be fit to the target fallen

material and down-hole conditions is important, too.

Engaging the Fish

Hooks and Latching Tools

Source: Australian Driling Industry Trining Committee

Figure 3 Fishing Tools (1/2)

DDCAP Technical Manual for Tool Fishing and Well Rehabilitation

For Technical Support Plan for the Drillers in DDCA

13 WELL REHABILITATION (TA CODE 13)

13.1 PHENOMENAN AND CAUSES OF WELL DETERIORATION (TA CODE 13-1)

13.1.1 WELL FAILURE BY INCRUSTATION

Chemical and biological incrustations are major causes of well failure. Water quality chiefly

determines the occurrence of incrustation. The surface characteristics of the screen itself may also

play a part in regulating the rate at which incrustation occurs. If the screen is constructed of

rough-surface metal, for example, incrustants may build up at a faster rate. The kind and amount of

dissolved minerals and gases in natural waters determine their tendency to deposit mineral matter

as incrustation.

Groundwater normally moves slowly and remains in contact with the minerals of the aquifer

material for hundreds or thousands of years in a quasi-chemical equilibrium with its environment.

Any change in the physical or chemical conditions (such as pumping a well) upsets the equilibrium

and may cause precipitation of relatively insoluble materials.

The incrustation often forms a hard, brittle, cement- like deposit similar to the scale found in water

pipes. It may also be soft, paste-like sludge or gelatinous material, depending on conditions.

The major forms of incrustation include:

 Precipitation of calcium and magnesium carbonates or their sulfates.

 Precipitation of iron and manganese compounds, primarily their hydroxides or hydrated

oxides.

 Slime-producing iron bacteria or other slime-forming organisms (biofouling).

(1) Causes of Carbonate Incrustation:

Chemical incrustation usually results from the precipitation of carbonates, mainly of calcium, from

groundwater in the proximity of the well screen. Other substances, such as aluminium silicates and

iron compounds, may also be entrapped in the scale-like carbonates that cement sand grains

together around the screen. The deposits fill the voids, and the flow of water into the well is

reduced proportionately.

The explanation is that calcium carbonate can be carried in solution in proportion to the amount of

dissolved carbon dioxide in the groundwater. The ability of water to hold carbon dioxide in solution

varies with pressure - the higher the pressure, the higher the concentration of carbon dioxide.

When water is pumped from a well in an unconfined aquifer the hydrostatic pressure in the deeper

portions of the aquifer is decreased with greatest change being at the well.

Because of the reduction in pressure, some carbon dioxide is released from the water. When this

occurs, the water is unable to carry its full load of dissolved calcium carbonate and part of this

material is precipitated onto the well screen and in the formation material adjacent to the well

screen.

Pumping a well in a confined aquifer produces a similar pressure reduction and resulting

precipitation.

Formation of calcium carbonate precipitate from calcium bicarbonate is the classic example:

Ca(HCO₃)₂

-∆P CaCO₃↓ + CO₂↑ + H₂O

where ∆P is a change in pressure.

Solubility of calcium bicarbonate is 1300 mg/l while the solubility of calcium carbonate is 13 mg/l.

Carbon dioxide (CO₂) escapes when the head, or pressure, is reduced.

Magnesium bicarbonate changes to magnesium carbonate in the same manner when the carbon

dioxide is released, but magnesium carbonate incrustation occurs only in special instances because

DDCAP Technical Manual for Tool Fishing and Well Rehabilitation

For Technical Support Plan for the Drillers in DDCA

it is still soluble at concentrations over 5000 mg/l (Kemmer, 1979). Precipitation occurs, therefore,

only when the carbonate concentration exceeds this level.

(2) Causes of Iron and Manganese Incrustation:

Many rocks throughout the world contain iron and manganese, and are the source of iron and

manganese ions found in groundwater if the pH is about 5 or less.

Velocity- induced pressure changes due to pumping can disturb the chemical equilibrium of the

groundwater and result in the deposition of insoluble iron and manganese hydroxides. These

hydroxides are gel-like and may occupy relatively large volumes. Over time, they harden into scale

deposits.

The ferric oxide is a reddish brown deposit similar to rust, whereas the hydrated ferrous oxide is a

black sludge.

The insoluble manganese oxide is also black or dark brown.

Iron and manganese deposits are often found associated with calcium and magnesium carbonate

scale.

In the cone of depression around a well in an unconfined aquifer, air enters the voids and oxidizes

iron in the films of water adhering to individual sand grains. If pumping is started and stopped

intermittently, a coating of iron oxide can build up, thereby gradually reducing the void space in

this part of the formation. This action reduces the formation’s storage capacity in the vicinity of the

well, and the cone of depression enlarges more rapidly than it would otherwise.

(3) Well Failure Caused by Iron Bacteria:

Iron bacteria occur widely in wells open to the atmosphere when sufficient iron and/or manganese

are present in the groundwater in conjunction with dissolved organic material, bicarbonate, or

carbon dioxide.

The principal forms of iron bacteria plug wells by enzymatically catalyzing the oxidation of iron

(and manganese), using the energy to promote the growth of threadlike slimes, and accumulating

large amounts of ferric hydroxide in the slime.

In this process, the bacteria obtain their energy by oxidizing ferrous ions to ferric ions, which are

then precipitated as hydrated ferric hydroxide on or in their mucilaginous sheaths. Precipitation of

the iron and the rapid growth of the bacteria create a voluminous material that quickly plugs the

screen pores of the sediment surrounding the well bore.

DDCAP Technical Manual for Tool Fishing and Well Rehabilitation

For Technical Support Plan for the Drillers in DDCA

Sometimes the explosive growth rates of iron bacteria can render a well virtually useless within a

matter of months.

Many other forms of iron bacteria induce the precipitation of iron through nonenzymatic means.

Found almost everywhere in both water and soil, these bacteria promote precipitation of iron by:

 Raising the pH of the water through metabolic and photosynthetic processes.

 Changing the redox potential of the water by algal photosynthesis. In this process, oxygen

given off by plants increases the redox potential, thereby causing the precipitation of iron.

 Liberating chelated iron by inducing a breakdown in the bond between iron and oxalate,

citrate, humic acids, or tannins.

Many forms of enzymatic bacteria that could grow in water wells prefer water with the following

general physical and chemical characteristics:

 Has an iron content of 1 to 25 mg/l and contains only traces of organic matter.

 Low in oxygen, typically in the 0.1 to 1.0 mg/l range.

 Usually fresh.

 Contains over 20 mg/l carbon dioxide.

 Has a redox potential in the range of 200 to 300 millivolts (mv).

 Has a pH in the range of 6 to 7.6.

 Has a temperature from 40 to 60⁰F (4.4 to 15.6⁰C).

There are, however, other forms of iron bacteria that can grow in waters having extremely low pH

(2 to 6) and much higher temperatures [60 to 185⁰F (15.6 to 85⁰C)]

A second classification of iron bacteria is the one based on the physical form of the organisms.

There are three general forms:

 The capsulated coccoid form which consists of numerous short rods surrounded by a mucoid

capsule. The deposit surrounding the capsule is hydrous ferric oxide, a rust-brown

precipitate.

 The stalked iron-fixing bacteria composed of twisted bands resembling a ribbon or chain

with a bean-shaped bacterial cell at the end of the twisted stalk.

 The filamentous group that take different shapes and structures.

Under each form are numerous genera and species.

If the presence of iron bacteria is suspected in a well, samples of the organism can be obtained by

a filtering device attached to the discharge of the pump for one week. The water passing through

the filter during this period leaves a dark brown precipitate on the porcelain cover which can be

examined for iron bacteria by a qualified laboratory.

Another method of sample collection is to examine the material scraped from valves or pump

discharge lines from suspected wells, pump shaft seals, water closets, or small steel objects

suspended temporarily in the well.

However, unless a microscope of at least 1000X is available, it is best to send the samples to a

laboratory or firm familiar with iron bacteria identification.

(4) Prevention and Treatment of Incrustation Problems:

So far, means of preventing the incrustation of well screens has not been found. One unique

method does exist, however, that is designed to reduce the amount of iron incrusting materials

reaching the well screen. This method, called the Vyredox System, uses a series of injection wells

located in a circle around the production well. Oxygenated water is injected into the wells to

oxidize iron in solution and promote the growth of iron bacteria so that little iron reaches the

production well.

DDCAP Technical Manual for Tool Fishing and Well Rehabilitation

For Technical Support Plan for the Drillers in DDCA

For most wells where incrusting material cannot be removed before reaching the well, several

actions can be taken to delay incrustation and make it a less serious problem:

 The well screen should be designed to have the maximum possible inlet area to reduce the

flow velocity to a minimum through the screen openings.

 The well should be developed thoroughly.

 The pumping rate may be reduced and the pumping period increased, thereby decreasing

entrance velocities.

 The pumping load may be divided among a larger number of smaller diameter wells instead

of obtaining all of the supply from only one or a few larger diameter wells.

 A more frequent maintenance or cleaning procedure - by qualified water well contractor-

should be undertaken wherever local experience shows considerable difficulty from

incrustation.

In localities where incrustation is prevalent, samples of the incrusting material and water should be

analyzed. The proportions of the various materials shown by the analyses should indicate the kind

of treatment and the type of chemicals that would be most successful in recovering well yield.

13.1.2 WELL FAILURE FROM CORROSION:

Metals are generally extracted from ores of stable mineral compounds that are in physical and

chemical harmony with their natural environment. In the elemental state most metals are not

inherently stable.

In the environment, elemental metals naturally revert back into more stable mineral compounds.

This completely natural process is called corrosion. It changes the physical and chemical properties

of metals, frequently destroys the usefulness of of fabricated metallic articles or structures, and may,

over time, reduce or destroy metal products.

Corrosion can severely limit the useful life of water wells in four ways:

 Enlargement of screen slots or development of holes in the casing, followed by sand

pumping.

 Reduction in strength, followed by failure of well screen or casing.

 Deposition of corrosion products, thereby blocking screen-slot openings and reducing yield.

 Inflow of low-quality water caused by corrosion of the casing.

(1) Chemical and Electrochemical Corrosion:

Corrosion results from chemical and electrochemical processes. Chemical corrosion occurs when a

particular constituent is present in water in sufficient concentration to cause rapid removal of

material over broad areas. Commonly these constituents are carbon dioxide, oxygen, hydrogen

sulfide, hydrochloric acid, chloride, and sulfuric acid.

Chemical corrosion can cause severe damage in wells, regardless of the amount of total dissolved

solids. The number of wells affected by chemical corrosion is, however, small compared to those

affected by electrochemical corrosion.

In electrochemical corrosion, flow of an electric current facilitates the corrosive attack on a metal.

Two conditions are necessary:

 A difference of an electrical potential on metal surfaces.

 Water containing enough dissolved solids to be a conductive fluid (electrolyte).

A potential (electrical) difference may develop between two different kinds of metals, or between

nearby but separate areas on the surface of the same metal.

Difference in potential on the same steel pipe, for example, can occur:

DDCAP Technical Manual for Tool Fishing and Well Rehabilitation

For Technical Support Plan for the Drillers in DDCA

 At heat affected areas around welded joints.

 At heated areas around torch-cut slots.

 At work-hardened areas around machine-cut slots.

 At cut surfaces of exposed threads at pipe joints.

 At breaks in surface coatings such as paint and mill scale.

In the above cases both a cathode and an anode develop, and metal is removed from the anode.

Bimetallic corrosion results when two different metals are in contact and immersed in an

electrolyte. A galvanic cell is created an corrosion occurs. A well screen made of two different

metals, such as low-carbon steel and stainless steel, will be damaged because the mild-steel portion

is corroded by the galvanic action.

When electrochemical corrosion takes place, corrosion products may be deposited at the cathode.

These deposits are usually voluminous. If iron or steel is corroded, the corrosion products are iron

combined with other elements and are normally ferric hydroxide or ferric oxide.

Deposition of corrosion products that results in blocked screen-slot openings and reduced well

yields is evidence of electrochemical corrosion.

DDCAP Technical Manual for Tool Fishing and Well Rehabilitation

For Technical Support Plan for the Drillers in DDCA

13.2 METHODS OF WELL REHABILITATION (TA CODE 13-2)

13.2.1 GENERAL

The major purposes of well rehabilitation are:

(1) To revive the well yield by cleaning the clogged screen and neighbouring aquifer

(2) To remove the sedimentation of sand at the bottom of a well

(3) To repair the damaged screen and/or casing which produce sand and/or clay into the pumped

water

For above (1), mechanical methods such as air-lifting, bailing, brushing, swabbing etc., and

chemical methods using acid are used.

For (2) air-lifting or bailing is used.

The countermeasures for (3) need more complex and expensive process. Double-casing methods

are commonly used if the diameter of internal casing to be installed is sufficiently enough to install

the pump. Principles of the above methods are described below.

13.2.2 MECHANICAL CLEANING

Mechanical cleaning is the method of removing scale, sand, silt which clogs the screen and

neighbouring aquifer by hydraulic force and/or direct physical contact of cleaning devises. The

following methods are generaly used (See Figure 5 and Figure 6).

(1) Bailing

(2) Brushing

(3) Jetting

(4) Pumping/Water Injection

Bailing

Swabbing

DDCAP Technical Manual for Tool Fishing and Well Rehabilitation

For Technical Support Plan for the Drillers in DDCA

13.2.3 CHEMICAL CLEANING

Mechanical methods are effective for the cleaning of the scales

on the suface of screen and casing. However, the effects

often do not reach to the inside of the neighbouring aquifer.

In this case, chemical method is used together with mechanical

method.

Various types of chemical agent for the well rehabilitation are

available for the purposes of the decomposition of scale,

disinfection of iron bacteria etc.

The instruments of chemical injection are shown in Figure 7.

Source National Water Well Association of Japan

Figure 7 Installation of Chemical

Cleaning

13.2.4 SEDIMENTATION REMOVAL

The pumped water contains certain amount of sand. The sand is deposited at the bottom of well

during the pumping operation. This sand deposit may cause the elvation of sand content in the

pumped water and/or decrease of water yield due the clogging of screen.

The deposited of sand shall be periodically removed by the measures of air-lifting and/or bailing

(See Figure 8)

Air-Lifting Method

Output (2) List of Number of Drilled Boreholes per Year

Table 1table shows number of drilled borehole per year. Total number of drilled borehole up to 2011/2013 is 12,932.

Table 1 Number of drilled boreholes per year

Financial

Borehole

Financial

Borehole

Financial

Borehole

Financial

Borehole

Financial

Borehole

Year

Drilled

Year

Drilled

Year

Drilled

Year

Drilled

Year

Drilled

19301931

1950-1951

1970-1971

144

1990-1991

151

2010-2011

244

1931-1932

1951-1952

1971-1972

272

1991-1992

186

2011-2013

269

1932-1933

1952-1953

1972-1973

286

1992-1993

152

1933-1934

1953-1954

1973-1974

314

1993-1994

139

1934-1935

1954-1955

1974-1975

291

1994-1995

212

1935-1936

1955-1956

1975-1976

284

1995-1996

1936-1937

1956-1957

1976-1977

253

1996-1997

335

1937-1938

1957-1958

1977-1978

193

1997-1998

352

1938-1939

1958-1959

1978-1979

156

1998-1999

505

1939-1940

1959-1960

1979-1980

150

1999-2000

583

1940-1941

1960-1961

1980-1981

282

2000-2001

404

1941-1942

1961-1962

1981-1982

110

2001-2002

390

1942-1943

1962-1963

1982-1983

2002-2003

422

1943-1944

1963-1964

1983-1984

133

2003-2004

516

1944-1945

1964-1965

1984-1985

240

2004-2005

485

1945-1946

1965-1966

1985-1986

2005-2006

466

1946-1947

1966-1967

1986-1987

193

2006-2007

467

Output (4) Requirement completed

1. CURRENT STATUS OF DATA MANAGEMENT OF DDCA

DDCA started drilling works since 1931 when it was the former Drilling Department of MoW

and continues drilling works after the transition to DDCA in 1997. Total number of boreholes

drilled by DDCA is approximately 10,000. Paper-based borehole completion reports are

principally stored in registry room of DDCA. However, most of the borehole completion

reports of former Drilling Department are stored in Water Resources Department (WRD) of

MoW and in the DDCA Office in Dodoma.

Currently, the completion report is submitted to Basin Water Office and client after approval of

DDCA headquarters. The report submitted is stored in DDCA branch office in Dodoma. The

staffs who analyze the data go to refer to the stored reports. The flow of preparing the report

is shown in Figure 1.

Related Sections of DDCA

Client and

DSM Head

AutoCAD

other related

Site

Analysis

Registry Room

Quarters

Room

parties

Hand writing

[Hydro-geologist]

Check and

Drilling Report by

Drawn with

Geological

instructions

Rig in charge

AutoCAD

description and

of typing

pumping test

analysis

[DPO or

Typing up

Zonal

manager]

Check

Final check

[Basin Office]

and signature

Receive

signed report

Store a copy

of signed

report

Pumping Test

[Client]

in charge

Receive

signed report

[Laboratory]

Water Quality

Analysis

[Dodoma

DDCA

Branch

office]

Store report

Figure 1: Flow of current organization of report

2. EXISTING WELL COMPLETION REPORT

The well completion reports include two types of forms one is the old forms which had been

used 1931 to 1946,the other one is the existing form currently used(form 1).The forms include

on drilling work, pumping test, water quality analysis. They consistof the following seven

types of forms:

1) cover page, 2) drilling record, 3) well section drawing, 4) step pumping test result, 5)

constant rate pumping test result, 6) recovery test result, and 7) water quality analysis

result.Among the above, the form 2) and 3) are prepared by the drilling teams.

They are prepared in hand writing by each Rig in Charge and sent to the main office in Dar es

Salaam through the Zonal Manager or Drilling Project Officer (DPO). After the examination of

the Head of Drilling Section, the form 2) is typed up in the registry room and the form 3) is

prepared with Auto-CAD in the drawing room. The forms 4) to 6) are prepared by the

pumping test teams. They are filled in hand writing and checked up by the Drilling Manager,

then typed up with MS-Word in the registry room. The typed up reports of the drilling work

and the pumping test are examined by the Drilling Manager. After that they will be approved

by CEO, to submit to the clients together with the form 7) to be prepared in the laboratory and

the form 1) cover page as well.

The set of the well completion report are shown in the Appendices 1-1 to 1-6. The old form is

shown in Appendix 1-2, while the form 1 is shown in Appendix 1-3.

3. INTRODUCTION OF NEW DATABASE SYSTEM

The purpose of the database is to provide the well data which facilitate the private company to

make a proper drilling plan when they start the drilling work in the areas where they do not

have experiences.

Currently, the existing well completion reports are stored in the DDC ’s headquarters in Dar es

Salaam, DDCA branch office in Dodoma and Water Resource Department (WRD) of MoW in

Dodoma. The work of the Contractor includes the data entry of those reports into the

database.After the data entry of all existing well completion reports, DDCA staffs shall continue

the entry of the new coming data. The database shall be constructed according to the

following principles so that DDCA can update the database periodically.

 The Software shall be MS-Excel as a versatile and popular one. This enables the DDCA

Output (4) Requirement completed

staffs to continue the update and maintenance of the database by themselves.

 Too much additional tasks for the updating of new database by DDCA shall be avoided.

Therefore, the change from the existing report making system shall be as less as possible.

Necessary consideration shall be taken such as the utilization of the typed-up data of

handwriting report in existing report as inputs to new database.

 Many data items in the database can be commonly used with the “Well Database in

African Countries (WDAF)” of JIC . The database shall be equipped with a function for

the easy transferring of data to the “ frican Countries Well Database” at the same time,

shall be added to the database.

4. REVISION OF FORMS

The form

2) was examined and revised upon the commencement of the database

construction.Hereafter, the existing form is called as “Form 1” (refer to the Appendix 1-2) and

the revised form is called as “Form 2” (refer to the Appendix 2). The purpose of the revision

was to add more information related to well location, well structure and drilling work record.

However, it was considered not to make the staffs spare much time for entering those

additional data. So the existing form has been utilized and only minimal items were added.

The Form 1 consists of the following items:

1) general description of the stratum, 2) record of water strike, 3) drilled diameter and depth,

4) record of casing screen, 5) record of backfilling, 6) record of gravel, 7) record of drilled

method and any other general description.

The column added in the Form 2 is as below.

(1)

General information

The column for entering either borehole newly drilled or rehabilitated was added.

The column for entering GPS coordination was added. The coordination system of GPS was

defined as Arc 1960 UTM.

The column for entering ward, village /street and sub-village were added.

The column for entering the survey reference number of the geophysical survey was added.

(2)

Description of the stratum

The column for entering the water strike was added.

(3)

Record of water strike

The column for entering water yield at each water strike depth was added. This information

is important to identify which aquifer was the major one.

The columns for entering the major aquifer and recovered water level were added.

(4)

Drilled diameter and depth

No addition

(5)

Record of casing and screen

The column for entering the position of screen was added.

The columns for screen diameter and depth were added in order to record the telescopic type

casing and screen.

The column for entering the diameter and depth of conductor casing and surface casing were

added.

The column for entering the hole uncased was moved to this section from the section 5 Finish

of Section Uncased of Form 1.

(6)

Finish of Section Uncased and Gravel Screen

5) Finish of Section Uncased and 6) Gravel Screen in Form 1 were combined to be 5) Clearance

Fill Up. The columns for entering Sealing Above Gravel Up To, Back Filling Up To and Sanitary

Sealing were added.

(7)

Drilling Method

The format was changed so that the data on depth and drilling method shall be filled.

The form of drilling work record revised as the above (Form 2) is shown in Appendix 2.

5. DATA SHARING WITH JICA’S WELL DATABASE

Many attributes in WDAF are same as or can be converted from those in WID.

The Appendices 3-1 to 3-4 show the list of the data items of WDAF. The attributes which can

be used for WDAF are shown with filled color (yellow: can be used directly, green: can be

converted by calculation).

Not all attributes of WID can be used in WDAF since the specifications of drilling works of DDCA

differ from those of the groundwater development projects of JICA. However, the

information related to well structure, pumping test and water quality analysis are almost

Output (4) Requirement completed

common between above two. So it is useful to produce the data sheet in WDAF’s format

from the data which are entered in WID.

Regarding the implementation of the database, placing all attributes in a data sheet in

MS-Excel will make the data entry works complicated.

The order of the entry sheet of WID is almost same as that of the entry to the well completion

report. Therefore, efficient way for the data entry is to place only the attributes for input in

data sheet in this order. In the same context, another datasheet in a WDAF’s format shall be

set in same excel book as WID’s data sheet and the data of WDAF’s shall be automatically

referred from WID’s data sheet by measures of by direct reference or calculation.

6. CHANGE OF DATABASE SOFTWARE TO MS-EXCEL

6.1 Database Structure in MS-Excel

As mentioned in Section 1.2, the well completion report except for the well section drawing

and the result of water quality analysis are typed up in the registry in the DDCA’s headquarters.

By using these data for the well completion forms as the input for WID, too much increase of

tasks on data entry clerks for the updating WID can be avoided and sustainable operation of

WID can be ensured.

For the pumping test result, only representative data of each pumping test shall be entered to

the WID. Detailed records of draw down etc. shall be entered and saved in the datasheet to

be prepared separately from WID’s self. Currently, the pumping test results are entered to

the forms in MS-Word. By changing these forms into MS-Excel, the data could be easily

utilized for making charts and interpretation of hydraulic constant, in case it is necessary.

WID shall be constructed in MS-Excel in order to allow DDCA staffs easily maintain it by

themselves. Technical support to improve the skills in MS-Excel of DDCA’s staff shall be

provided by the Contractor and JICA Expert Team, since there are currently no staffsthat have

enough skills for the operation and maintenance of the WID.

6.2 Information Retrieval from WID

The borehole data in the WID is helpful for private drilling companies to formulate their drilling

plan and to determine the drilling method. However, if DDCA is equipped with the capacity to

provide them with filtered and/or analysed data according to the needs of the private

companies, the technical support from DDCA will be more effective.

The area-wise analyse will be special useful for the private companies. The maximum,

minimum and average value of well depth, well structure and well yield by area will contribute

to the accuracy improvement of the drilling plan and to the prevention of risk to start the

drilling work in inexperienced area.

The existing well completion reports of DDCA include the data of only regions and districts as

the information of well locations but do not have that of wards, villages and GPS coordinates.

DDCA decided to start to record such important data by using the revised drilling record form

which contains the column for entering those data. It means that the new well data will

include this information. On the other hand, DDCA has a plan to start to collect the GPS

coordinates of existing wells and add them to the WID. The WID is expected to provide more

useful information with improved quality by the above updating.

Apart from the area-wise analysis, the analysis by different parameters such as year or drilling

method is one of the major advantages of database. In order to achieve this, DDC ’s staffs

need to acquire the skill of data analysis by MS-Excel.

Appendices

Appendix 1-1

Existing Well Completion Report Form Cover Page (Sample)

Appendix 1-2

Existing Well Completion Report Form Drilling Work Record (Old form) (Sample)

Appendix 1-3

Existing Well Completion Report Form Drilling Work Record (Form 1) (Sample)

Appendix 1-4

Existing Well Completion Report Form Borehole Section Drawing (Sample)

Appendix 1-5

Existing Well Completion Report Form Constant Pumping Test Result (Sample)

Appendix 1-6

Existing Well Completion Report Form Recovery Test Result (Sample)

Appendix 1-7

Existing Well Completion Report Form Water Quality Analysis Result (Sample)

Appendix 2

Revised Well Completion Report (Form 2) (Sample)

Appendix 3-1

African Countries Well Database Data Item(Well Location and Specification)

Appendix 3-2

African Countries Well Database Data Item(Pumping Test, Pump Installation

and Facility)

Appendix 3-3

African Countries Well Database Data Item (Water Quality Analysis)

Appendix 3-4

African Countries Well Database Data Item (Project Information)

Appendix 3-1

African Countries Well Database Data Item(Well Location and Specification)

Group

Category

Data Item of African

Method Extracted

Remarks

Countries Well Database

from DDCA database

Well Location

Country No.

For Tanzania

Country Code of Tanzania

Country

For Tanzania

Tanzania

Region

Direct Reference

Added in Revised Form

District

Direct Reference

Division

Direct Reference

Added in revised form

Village

Direct Reference

Added in revised form

Community or Site Name

Direct Reference

Borehole No. in This

No data

Project

Registered Boreholen No.

Direct Reference

Latitude

No data

Longitude

No data

Altitude

No data

UTM Zone

Direct Reference

Added in revised form

UTM X

Direct Reference

Added in revised form(Arc1960)

UTM Y

Direct Reference

Added in revised form(Arc1960)

Coordinate Collected

No data

Point

Accuracy

No data

Map

No data

Well SpecificatioWell Specifications

Positive or Negative

No data

Can be calculated by setting

Borehole

criteria for success

Reason for Negative

No data

Can be calculated by setting

criteria for success

Positive or Negative

No data

Can be calculated by setting

quality

criteria for potable water quality

standard

Remarks

No data

New Construction /

Direct Reference

Added in revised form

Rehabilitation

Geophysical Survey

Present/Absent

No data

Survey Data

No data

Survey No.

Direct Reference

Added in revised form

Drilling Date

Direct Reference

Date of completion of drilling

Drilling Diameter

Bit Type

Calculation

Calculated from drilling diameter

Drilling Diameter

Calculation

Calculated from drilling diameter

Drilling Liquid

Calculation

Calculated from drilling diameter

Drilling Depth

Direct Reference

Drilling Information

Drilling Rate

No data

Water Strike Depth or Mud

Direct Reference

Water Lost Depth

Water Yield by Air

Direct Reference

Confirmed water yield

Lifting

Acceptable Yield or not

No data

Casing

Installation

Calculation

Calculated from whether or not

casing data exists

Material

Direct Reference

Diameter Size

Direct Reference

Installed Depth

Direct Reference

Top Screen Top

Direct Reference

Top Screen Bottom

Direct Reference

2nd Screen Top

Direct Reference

2nd Screen Bottom

Direct Reference

3rd Screen Top

Direct Reference

3rd Screen Bottom

Direct Reference

4th Screen Top

Direct Reference

4th Screen Bottom

Direct Reference

5th Screen Top

Direct Reference

5th Screen Bottom

Direct Reference

6th Screen Top

Direct Reference

6th Screen Bottom

Direct Reference

7th Screen Top

Direct Reference

7th Screen Bottom

Direct Reference

Toltal Screen Length

Direct Reference

Lithological Log

Geological Column

Direct Reference

Borehole Logging

Logging data

No data

Item 1

No data

Item 2

No data

Item 3

No data

Item 4

No data

Water Level

Measuring Level

No data

Height from Ground Leve

No data

Natural Water Level

Direct Reference

Image of Lithogical

Column Image

Direct Reference

: Data directly to be used in African Countries Well Database

　:　Data to be extracted from African Countries Well Database by Calculation

A-9

Appendix 3-2

African Countries Well Database Data Item(Pumping Test, Pump Installation

and Facility)

Group

Category

Data Item of African

Method Extracted

Remarks

Countries Well Database

from DDCA database

Pumping Test

Pumping Test Date

Test Starting Date

Direct Reference

Step Drawdown Test

1st Step Discharging Rate

Direct Reference

1st Step Pumping Time

Direct Reference

1st Step Dinamic Water

Direct Reference

Level

2nd Step Discharging Rate

Direct Reference

2nd Step Pumping Time

Direct Reference

2nd Step Dinamic Water

Direct Reference

Level

3rd Step Discharging Rate

Direct Reference

3rd Step Pumping Time

Direct Reference

3rd Step Dinamic Water

Direct Reference

Level

4th Step Discharging Rate

Direct Reference

4th Step Pumping Time

Direct Reference

4th Step Dinamic Water

Direct Reference

Level

5th Step Discharging Rate

Direct Reference

5th Step Pumping Time

Direct Reference

5th Step Dinamic Water

Direct Reference

Level

6th Step Discharging Rate

Direct Reference

6th Step Pumping Time

Direct Reference

6th Step Dinamic Water

Direct Reference

Level

7th Step Discharging Rate

Direct Reference

7th Step Pumping Time

Direct Reference

7th Step Dinamic Water

Direct Reference

Level

Constant Dicharge Ra

Starting Water Level

Direct Reference

Discharging Rate

Direct Reference

Pumping Time

Direct Reference

Draw Down Level

Direct Reference

Specific Capacity

Calculation

Recovery Test

Measured Time

Direct Reference

Recovered Water Level

Direct Reference

Pumping Test Interpr

Transmissivity

No data

Permeability

No data

Transmissivity

No data

Permeability

No data

Image of Pumping Tes

Analyzed Data

No data

Pump Test Image

No data

Water Supply PumpPump for Water Suppl

Type

No data

Model

No data

Specification

No data

Installed Depth

No data

Superstructure

Platform

No data

Constructional Purpose

No data

Holder

No data

Image

No data

: Data directly to be used in African Countries Well Database

　:　Data to be extracted from African Countries Well Database by Calculation

A-10

Appendix 3-3

African Countries Well Database Data Item (Water Quality Analysis)

Group

Category

Data Item of African

Method Extracted

Remarks

Countries Well Database

from DDCA database

Water Quality AnaWater Quality Analys

Data Present or not

Calculation

Calculated from whether or not

data exists

Color

No data

Color

No data

Color mgPt/l

No data

Color mgPt/l

Direct Reference

Turbidity

No data

Turbidity

Direct Reference

Odor

No data

Taste

Direct Reference

Temperature

No data

ｐH

Direct Reference

Oxidation-reduction

No data

Potential ORP

Conductivity

Direct Reference

Total Dissolved Solid TDS

No data

Total Dissolved Solid TDS

Direct Reference

Total Hardness TH

No data

Total Hardness TH

Direct Reference

Alminium Al

No data

Alminium Al

No data

Ammonium NH3

No data

Ammonium NH3

Direct Reference

Iron Fe

No data

Iron Fe

Direct Reference

Fluoride F

No data

Fluoride F

Direct Reference

Manganese Mn

No data

Manganese Mn

Direct Reference

Nitrate NO3

No data

Nitrate NO3

Direct Reference

Nitrit NO2

No data

Nitrite

Direct Reference

Disolved Oxygen DO

No data

Disolved Oxygen DO

No data

Phosphorus P

No data

Phosphorus P

Direct Reference

Phosphate PO43-

No data

Phosphate PO43-

No data

Sodium Na

No data

Sodium Na

Direct Reference

Zinc Zn

No data

Zinc Zn

Direct Reference

Calcium Ca

No data

Calcium Ca

Direct Reference

Magnesium Mg

No data

Magnesium Mg

Direct Reference

Potassium K

No data

Potassium K

Direct Reference

Bicarbonates HCO3-

No data

Bicarbonates HCO3-

No data

Carbonate CO3-

No data

Carbonate CO3-

Direct Reference

Chloride Cl-

No data

Chloride Cl-

Direct Reference

Sulfate SO42-

No data

Sulfate SO42-

Direct Reference

Alcalinite

No data

Alcalinite

Direct Reference

TAC

No data

Lead Pb

No data

Lead Pb

Direct Reference

Palladium Pd

No data

Palladium Pd

No data

Mercury Hg

No data

Mercury Hg

Direct Reference

Selenium Se

No data

Selenium Se

No data

Arsenic As

No data

Arsenic As

No data

Boron B

No data

Boron B

No data

Cadmium Cd

No data

Cadmium Cd

Direct Reference

Copper Cu

No data

Copper Cu

Direct Reference

Chromium Cr

No data

Chromium Cr

Direct Reference

Sexivalent Chromium Cr6+

No data

Sexivalent Chromium Cr6+

No data

General Bacteria

No data

General Bacteria

No data

Total Coliform

No data

Total Coliform

Direct Reference

Facal Coliform, E-Coli

No data

Facal Coliform, E-Coli

Direct Reference

: Data directly to be used in African Countries Well Database

　:　Data to be extracted from African Countries Well Database by Calculation

A-11

Appendix 3-4

African Countries Well Database Data Item (Project Information)

Group

Category

Data Item of African

Method Extracted

Remarks

Countries Well Database

from DDCA database

Project Information

Project Name

No data

Consultant

No data

Contractor

No data

Year Submitted Report

No data

Construction Works

No data

Started

Construction Works

No data

Finished

Drilled Boreholes

No data

Positive Boreholes

No data

Negative Boreholes

No data

Q'ty of Negative Yield

No data

Q'ty of Negative quality

No data

Q'ty of Boreholes the

No data

reason for rejection is

not knowable

Success Rate

No data

Q'ty of Rehabilitation

No data

Remarks

No data

Project Summary (Jp)

No data

Project Summary (English)

No data

A-12

Table of Contents

1. ATTRIBUTES TO BE STORED IN DATABASE

2. DESCRIPTION OF ATTRIBUTES TO BE STORED IN DATABASE

3. CONTENTS OF REPEATING GROUP AND MAXIMUM NUMBER OF DATA

4. DATABASE DESIGN

5: DATA ENTRY AND DATABASE MAINTENANCE ORGANIZATION

6: COMPUTER NETWORKING SYSTEM

7. TECHNICAL SUPPORT FOR UPDATE AND MAINTENACE OF DATABASE

Tables

Table 1: Description of Attribute

Figures

Figure 1: Attributes to be Stored in Database

Figure 2: Roles of Concerned Staffs and Flow of Well Completion Report Preparation

................................................................................................................................. 7

Figure 3: Computer Network

Output (5) System Analysis Completed

2. DESCRIPTION OF ATTRIBUTES TO BE STORED IN DATABASE

Table 1: Shows the description of each attribute to be stored in the database.

Table 1: Description of Attribute

No.

Data item

Description

Types of data

Remarks

Region

Locality information. Region of the drilling point.

text

Unique to a well

District

Locality information. District of the drilling point.

text

Unique to a well

Ward

Locality information. Ward of the drilling point.

text

Unique to a well

Village/Street

Locality information. Village/Street of the drilling point.

text

Unique to a well

Sub Village

Locality information. Sub Village of the drilling point

text

Unique to a well

Locality information. Name of the belonging facility/house/area

Location / Area

text

Unique to a well

etc.

Work Scope

New borehole construction, rehabilitation or any other scope

text

Unique to a well

Drilled by (Rig No.)

Rig No. of the drilling rig which drilled the borehole

Number

Unique to a well

Drilled by (Rig Type)

Rig type of the drilling rig which drilled the borehole

text

Unique to a well

Borehole No.

Officially registered number with the water office

Number

Unique to a well

UTM Zone

Locality information. UTM zone of the drilling point

Text

Unique to a well

Coordinate (X)

Locality information. UTM (X) of the drilling point

Number

Unique to a well

Coordinate (Y)

Locality information. UTM (Y) of the drilling point

Number

Unique to a well

Elevation

Locality information. Elevation of the drilling point

Number

Unique to a well

Applicant id

Client id registered in DDCA

Number

Unique to a well

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

Applicant Name

Client Name

Text

Unique to a well

Applicant Address

Client Address

Text

Unique to a well

Date of Commencement

Date of commencement of the drilling work

Date

Unique to a well

Date of Completion

Date of completion of the drilling work

Date

Unique to a well

Survey Ref. No.

Ref. No of survey which is for the drilling point

Number

Unique to a well

Drawing

Number of drawing belonging to this report

Number

Unique to a well

Name of Driller in charge

Name of driller in charge who drilled the borehole

Text

Unique to a well

Remarks

Any remarks regarding drilling works

Text

Unique to a well

Signature

Unique to a well

Strata from

Top depth of distribution range of an each lithological description

Number

Many to each well

Bottom depth of distribution range of an each lithological

Strata to

Number

Many to each well

description

General Description

Lithological description of cuttings

Text

Many to each well

Water Strike

The zone where the water came from

Number

Many to each well

Strike at Depth from

Starting depth of the zone where the water increased

Number

Many to each well

Strike at Depth to

Ending depth of the zone where the water increased

Number

Many to each well

Yield

Measured water yield at the end of the zone the water increased

Number

Many to each well

Water Level Rose to

Water level at the end of drilling work

Number

Unique to a well

Yield Tested

Yield at the end of development

Number

Unique to a well

Water Quality to Taste

Taste of water

Text

Unique to a well

Depth on Completion

Total drilling depth

Number

Unique to a well

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

Diameter Drilled

Diameter and drilled borehole

Number

Many to each well

Depth Drilled

Drilling depth of each diameter

Number

Many to each well

Casing Type

PVC, steel, FRP etc.

Text

Many to each well

Casing Diameter

Diameter of the installed casing

Number

Many to each well

Casing Length

Length of the installed casing

Number

Many to each well

Casing Thickness

Thickness of the installed casing

Number

Many to each well

Screen Position from

Top depth of each screen position

Number

Many to each well

Screen Position to

Bottom depth of each screen position

Number

Many to each well

Casing above GL

Remnant of the casing standing above ground level

Number

Unique to a well

Top of Casing

Material or type of top plug

Text

Unique to a well

Secured/Top Plug

Bottom End of Casing

Protected with Bottom

Material or type of bottom plug

Text

Unique to a well

plug

Hole Uncased up to

Top depth of zone without permanent casing

Number

Unique to a well

Backfilled to

Top depth of bottom back filling

Number

Unique to a well

Filled with

Material for backfilling

Text

Unique to a well

Average Size

Average size of the material of backfilling

Number

Unique to a well

Other Method

Text

Unique to a well

Length

Length of the installed casing

Number

Unique to a well

Conductor Casing

Diameter of the conductor casing

Number

Unique to a well

Diameter

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

Conductor Casing GL to

Installation depth of the conductor casing

Number

Unique to a well

Surface Casing GL to

Installation depth of the surface casing

Number

Unique to a well

Diameter from

Top depth of gravel zone

Number

Unique to a well

Diameter to

Bottom depth of gravel zone

Number

Many to each well

Gravel Type

Gravel type

Text

Many to each well

Sealing Position

Top depth of sealing position above gravel

Number

Unique to a well

Sealing Material

Material of sealing above gravel

Text

Unique to a well

Average Size

Average size of the gravel

Number

Unique to a well

Inserted from

Top depth of the gravel position

Number

Unique to a well

Inserted to

Bottom depth the gravel position

Number

Unique to a well

No. of Cubic Meter

Volume of gravel

Number

Unique to a well

Inserted

Bottom Backfilling up to

Top depth of bottom backfilling below permanent casing

Number

Unique to a well

Bottom Backfilling up

Material of bottom backfilling

Text

Unique to a well

Material

Bottom Backfilling up

Material size of bottom backfilling

Number

Unique to a well

Material Size

Gravel Filling up to

Top depth of gravel packing

Number

Unique to a well

Gravel Filling up Material

Material of gravel

Text

Unique to a well

Gravel Filling up Material

Size of gravel

Number

Unique to a well

Size

Sealing above Gravel up

Top depth of sealing position above gravel

Number

Unique to a well

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

Sealing above Gravel up

Material of sealing above gravel

Text

Unique to a well

Material

Backfilling up to

Top depth of backfilling above sealing

Number

Unique to a well

Backfilling up Material

Material of backfilling above sealing

Text

Unique to a well

Backfilling up Material

Size of material of backfilling above sealing

Number

Unique to a well

Size

Sanitary Sealing from

Bottom depth of sanitary sealing (it should be "backfilling up to")

Number

Unique to a well

Sanitary Sealing to

Top of sanitary sealing (normally it is GL)

Number

Unique to a well

Sanitary Sealing Material

Material for sanitary sealing

Text

Unique to a well

Method Name

Drilling method

Text

Many to each well

From

Started depth of the drilling method

Number

Many to each well

ended depth of the drilling method

Number

Many to each well

Date from

Commencement date of pumping test

Date

Unique to a well

Step SWL

Static water level at the beginning of step drawdown test

Number

Unique to a well

Step Discharge Rate

Discharge rate of the step drawdown test

Number

Many to each well

Step Pumping Time

Pumping time of the step

Number

Many to each well

Step DWL

Drawdown water level of the step

Number

Many to each well

Constant SWL

Static water level at the beginning of constant test

Number

Unique to a well

Constant Discharge Rate

Discharge rate of the constant test

Number

Unique to a well

Constant Pumping Time

Pumping time of the constant discharge test

Number

Unique to a well

Constant DWL

Drawdown of the constant test

Number

Unique to a well

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

Recovery Measuring

Duration of recovery measuring

Number

Unique to a well

Time

Recovery WL rose to

Water level at the end of the recovery test

Number

Unique to a well

Conducted for

Purpose of the pumping test

Text

Unique to a well

Conducted by

Operator of the pumping test

Text

Unique to a well

SWL at

Static water level at the beginning of the pumping test

Number

Unique to a well

Draw down

Drawdown of the pumping test

Number

Unique to a well

Yield

Yield of the pumping test

Number

Unique to a well

Type of pumping test like preliminary, step drawdown, constant

Type of Pumping Test

Text

Unique to a well

rate, or recovery.

100

No. of Steps

Number of steps. Constant rate test and recovery is one step.

Number

Unique to a well

Out Flow Measurement

101

The volume of the equipment to measure the discharging.

Number

Unique to a well

with Tank Capacity of

102

Airlift Size

Airlift pipe size

Number

Unique to a well

103

ALSP laced at depth of

The length of the airlift pipe

Number

104

Pump Cylinder Size

Pump cylinder size

Number

Unique to a well

105

PCS Placed at Depth of

Pump cylinder setting depth

Number

Unique to a well

106

Equipment

Text

Unique to a well

107

Pump Model

Pump model

Text

Unique to a well

108

EPM Placed at Depth of

Pump setting depth

Number

Many to each well

109

Date

Started date of pumping test

Date

Many to each well

110

Time Hour

Measured time; hour

Number

Many to each well

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

111

Time Minute

Measured time; minute

Number

Many to each well

112

Meter

Measured value: meter

Number

Many to each well

113

Centimeter

Measured value: centimeter

Number

Many to each well

114

Yield LPH

Discharging

Number

Many to each well

Discharge Measured

115

Equipment to measure discharging

Text

Many to each well

Using

116

Remarks

Remarks regarding the pumping test

Text

Many to each well

117

Date

Starting date of recovery test

Date

Many to each well

118

Time Hour

Measured time; hour

Number

Many to each well

119

Time Minutes

Measured time; minute

Number

Many to each well

120

Time Difference

Total duration from the beginning of constant test

Number

Many to each well

121

WL Raised to

Recovered water level

Number

Many to each well

122

Additional Notes

Additional notes

Text

Many to each well

123

Remarks

Remarks regarding the pumping test

Text

Many to each well

124

Turbidity

One of parameter of water quality

Number

Unique to a well

125

Color

One of parameter of water quality

Text

Unique to a well

126

Settable Matter

One of parameter of water quality

Text

Unique to a well

127

One of parameter of water quality

Number

Unique to a well

128

Taste

One of parameter of water quality

Text

Unique to a well

Conductivity at

129

One of parameter of water quality

Text

Unique to a well

25C/Salinity

130

Total Dissolved Solid

One of parameter of water quality

Number

Unique to a well

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

Total Non filterable

131

One of parameter of water quality

Number

Unique to a well

Residual at 105C

Total Volatile and Fixed

132

One of parameter of water quality

Number

Unique to a well

Residual at 550C

133

Alkalinity (as CaCo3)

One of parameter of water quality

Number

Unique to a well

134

Phenolphthalein

One of parameter of water quality

Number

Unique to a well

135

Total Alkalinity

One of parameter of water quality

Number

Unique to a well

136

Hardness (as CaCo3)

One of parameter of water quality

Number

Unique to a well

137

Carbonate

One of parameter of water quality

Number

Unique to a well

138

Non Carbonate

One of parameter of water quality

Number

Unique to a well

139

Total Hardness

One of parameter of water quality

Number

Unique to a well

140

Calcium

One of parameter of water quality

Number

Unique to a well

141

Magnesium

One of parameter of water quality

Number

Unique to a well

142

Sodium

One of parameter of water quality

Number

Unique to a well

143

Potassium

One of parameter of water quality

Number

Unique to a well

144

Cadmium

One of parameter of water quality

Number

Unique to a well

145

Chromium

One of parameter of water quality

Number

Unique to a well

146

Copper

One of parameter of water quality

Number

Unique to a well

147

Iron

One of parameter of water quality

Number

Unique to a well

148

Lead

One of parameter of water quality

Number

Unique to a well

149

Manganese

One of parameter of water quality

Number

Unique to a well

150

Mercury

One of parameter of water quality

Number

Unique to a well

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

151

Zinc

One of parameter of water quality

Number

Unique to a well

152

Total Nitrogen

One of parameter of water quality

Number

Unique to a well

153

Ammonical Nitrogen

One of parameter of water quality

Number

Unique to a well

154

Organic Nitrogen

One of parameter of water quality

Number

Unique to a well

155

Nitrate Nitrogen

One of parameter of water quality

Number

Unique to a well

156

Total Phosphorus

One of parameter of water quality

Number

Unique to a well

157

Orthophosphate

One of parameter of water quality

Number

Unique to a well

158

Sulphate

One of parameter of water quality

Number

Unique to a well

159

Chloride

One of parameter of water quality

Number

Unique to a well

160

Fluoride

One of parameter of water quality

Number

Unique to a well

161

Others Total Coliform

One of parameter of water quality

Number

Unique to a well

162

Faecal Strep otococci

One of parameter of water quality

Number

Unique to a well

163

AsmgKMnO/L

One of parameter of water quality

Number

Unique to a well

164

BOD(5Days)

One of parameter of water quality

Number

Unique to a well

165

Chlorine Residual

One of parameter of water quality

Number

Unique to a well

166

Remarks

Remarks regarding water quality analysis

Text

Unique to a well

167

Note

Text

Unique to a well

168

Reporting Officer Name

Name of the laboratory which analysed water quality

Text

Unique to a well

169

Signature

Person who signed

Signature

Unique to a well

170

Position

Position of the signer

Text

Unique to a well

171

Ref No.

Reference number of the analysis

Number

Unique to a well

Output (5) System Analysis Completed

No.

Data item

Description

Types of data

Remarks

172

Telephone

Telephone number of the laboratory

Number

Unique to a well

173

Telegram of the laboratory

Number

Unique to a well

E-mail

174

E-mail address of the laboratory

Unique to a well

address

175

Fax No.

Fax number of the laboratory

Number

Unique to a well

Person or organization who requested the analysis. It may be

176

Analysis Requested by

Text

Unique to a well

DDCA

177

Dated

Analysis date

Date

Unique to a well

Date Received At

178

Date that the laboratory received the water sample

Date

Unique to a well

Laboratory

Date Collected For

179

Date that the water sample was collected at site

Date

Unique to a well

Analysis

Time Collected For

180

Time that the water sample was collected at site

Date

Unique to a well

Analysis

181

Temperature

Number

Unique to a well

182

Purpose of Sampling

Purpose of sampling

Text

Unique to a well

Preservative Added/Type

183

of Treatment to Water

Preservatives for the water sample before analysis if added

Text

Unique to a well

before Sampling

3. CONTENTS OF REPEATING GROUP AND MAXIMUM NUMBER

OF DATA

The attributes without filled color in the Appendix 4 are repeating groups to a well or a

pumping test (hereafter called as “repeating group”). Therefore, it is necessary to secure the

necessary numbers of columns which allows the maximum possible numbers of data in data

sheet in MS-Excel.

The contents of the repeating group and the maximum number of the data are described

below.

In case the data exceeds to the maximum number of the data, the necessary number of the

column in data sheet in MS-Excel shall be added.

(1) Strata

The record of strata includes the following attributes;

 Strata From: the depth of each starting stratum

 Strata To: the depth of each ending stratum

 Description of strata: description on each stratum

 Water Strike: whether or not there was water strike at each stratum

The division of the strata at each well is of two to three at minimum and more than 10 at most.

Accordingly, 20 numbers of the data would be enough for the record of strata.

Principally, all data shall be included in one data sheet. However, as the strata record has

many data, they shall be entered in separated data sheet. This makes the work of data entry

easier.

(2) Water Strike

The record of water strike includes the following attributes;

 Depth of Water Strike From: the starting depth of the water strike

 Depth of Water Strike To: the ending depth of the water strike

 Yield: Measured yield

The maximum number of the data shall be six since the supposed numbers of water strike are

zero to six.

Output (5) System Analysis Completed

(3) Drilled diameter/depth

The drilled diameter/depth includes the following attributes;

 Drilled Diameter: the diameter drilled in each drilling stage

 Drilled Depth: the depth drilled in each drilling stage

The number of the data item is equal to the number of drilling stage. Since DDCA has 1 to 3

drilling stages, the maximum number shall be three.

(4) Casing screen

The casing screen includes the following attributes. There are three data types i.e.

Specification on the casing, screen position and casing diameter/depth. The contents and the

maximum number of the each data are described as below.

1) Specification of casing

 Casing Type: material of the casing such as PVC, steel or stainless steel

 Casing Diameter: nominal diameter of the casing

 Casing Length: the total length of the installed casing

These attributes are for the production casing and screen. Normally, one type of the

productive casing screen is installed from top to bottom. However, for the large

diameter well, sometimes telescopic-type structure is used which are composed of large

diameter pump housing and other smaller casing and screen. In this case, the number of

the data becomes two.

Accordingly, the maximum number of the data shall be two.

2) Screen position

 Screen Positioned From: the top depth of each screen

 Screen Positioned To: the bottom depth of each screen

Normally, the screen is divided into one part to five. The maximum numbers of the data

in the WDAC were seven. Therefore, the same numbers i.e. 7 is used for the WID.

3) Casing diameter/depth

 Diameter From: the top depths of shallow part and deep part of production casing

 Diameter To: the bottom depths of shallow part and deep part of production casing and

screen

These attributes are for the record of the depth of pump housing, in case that

telescopic-type production casing and screen are used.

The number of the data is one, for normal straight-type casing screen and two for

telescopic-type casing and screen.

Accordingly, the maximum number of the data shall be two.

(5) Drilling method

The drilling method includes the following attributes;

 Method: To be selected from four types, i.e. mud rotary, air rotary, air percussion (DTH)

and cable tools

 From: the depth of starting each method

 To: the depth of ending each method

Normally, multiple drilling methods are used by DDCA for a borehole, depending on the type of

drilling equipment and/or geological condition.

Normally, as much as two methods are used

for a borehole while the all the four methods are used in some cases.

Accordingly, the maximum number of the data shall be four.

(6) Step pumping test

The step pumping test includes the following attributes;

 Step pumping test yield: final yield of each step

 Step pumping test pumping time: pumping time of each step

 Step pumping test dynamic water level: final dynamic level of each step

Normally, the numbers of step are four to five for DDCA. In WDAF, the maximum numbers of

step was seven. Therefore, the same number, 7, shall be applied in this database.

4. DATABASE DESIGN

Based on the above analysis, ER Diagram was designed (Figure 2). This design is used to

construct data entry system for existing borehole reports. After completion of data entry, the

entered data will be exported to excel format. The main components of excel database are

borehole data, pumping test data and water quality data.

5: DATA ENTRY AND DATABASE MAINTENANCE

ORGANIZATION

The WID will be updated by the new data entry from the drilling work record

form and pumping test record form which are filled by handwriting on site and

water quality analysis report which are prepared in the laboratory.

The rolls of concerned staffs with the preparation of the well completion report,

the update and maintenance of the WID are described below.

(1) Rig in charge

Each rig in charge of the drilling team fills in the drilling record form by

handwriting on drilling site and submits it to the Zonal Managers or DPOs.

(2) Zonal Managers and DPOs

The Zonal Managers or DPOs receive the drilling record form submitted from the

Rig in charge and forward it to the Head of Drilling Section of DDCA’s

Headquarters.

(3) Pumping test in charge

Pumping test in charge fills in the form by handwriting on site and submits it to

the Drilling Manager of DDC ’s headquarters.

(4) Hydrogeologist in Survey Section of the Technical Support Division in DDCA’s

headquarters

Hydrogeologist analyzes the drill cuttings on site or in DDC

’s headquarters and

prepares a casing programme. These results are supposed to inform the Rig in

charge.

He is responsible for the control of the survey reference numbers and informs

the Rig in charge of it.

He browses the WID for the purpose to check the record of strata and casing

program and to interpret the survey result.

(5) Water quality analysis laboratory

The water samples which are collected in the end of the pumping test will be

sent to the water quality analysis laboratory to conduct the analysis.

Output (5) System Analysis Completed

The water quality analysis laboratory will prepare the water quality analysis

report and submit it to the Head of Drilling Section.

(6) Head of Drilling Section of the DDCA’s Headquarters

The Head of Drilling Section examines the well completion report form

submitted from each staff in charge.

After the examination, he gives the instruction to the data entry clerk of the

registry room to finalize the drilling record form and pumping test record form by

data entry in WID and to finalize the well section drawing to the drawing room

by Auto-CAD.

He compiles the final version of the well completion report and submits it to the

CEO for his approval. After that, he submits it to the client.

He is responsible for the supervision of the entire process of preparation of the

well completion report, the update and the information retrieval from the WID

for providing data to the private drilling companies.

(7) Drawing room in the DDCA’s Headquarters

The well section drawings are prepared with Auto-CAD based on the handwritten

drilling work record form and well section drawing form after the examination of

the Head of Drilling Section.

(8) Registry Room in the DDCA’s Headquarters

After the examination by the Head of the Drilling Section, the handwritten

drilling work record form and the pumping test form are handed to the data

entry clerk of the registry room for finalization. The finalized forms are

submitted to the Head of Drilling Section.

(9) Computer room

The computer room is mainly in charge of the calculation related to the account

issues. This room is not directly related to the data entry to the WID.

However, the server computer is installed in this room and the staffs in this room

shall be of the network administrator.

(10) Data entry room

The data entry room is in charge of the management of the information related

to the contracts of drilling works such as contract prices, payment, clients and

contract specifications.

Though this room is not directly related to the data entry to the WID, this room

browses the WID for the purpose of comparing the contents of the contract and

work results such as specifications, resulted amount etc.

The rolls of the concerned staffs described above and the flow of

well

completion report preparation are shown in Figure 3.

Concerned Parties related to Well Completion Report Making and Database Maintenance

Drilling and

HQ Survey

HQ Head of

Recipients of

Section

HQ Registry

HQ Computer

Pumping Test

Laboratory

Drilling

HQ CEO

HQ Drawing Room

HQ Data Entry

Reports

(Hydrogeologiss

Room

Sites

Section

ts)

Report Making and Database Entry

Hand-writing

Li thological

Confi rmation

Entry to

report by ri g

log and

and

database and

in charge

pumpingtest

instruction to

finalization of

interpretation

data entry

well

To Client

and

compl etion

finalization

form and

Finalization of

Well

pumping test

Structure

form

Submitted to

Section by

DPO or Zona l

AutoCAD

To Basin

Ma na ger

Water Office

Final

confi rmation

Stori ng copies

Hand-writing

a t Centra l

report by

Approval and

Zone Office of

pumping test

Signature

DDCA and

technician

WRD of MoW

in Dodoma

Water Quality

Submissionto

Analysis

Cl i ent a nd

rel a ted

orga nizations

Reading and Maintenance of Database

Reading of

Ma i ntenance

Network

Reading

Database for

of database

Administration

database for

checki ng

and

checki ng

oflithology and

information

contra ct

database and

retri eval from

condi tions

for reference

database

for the

geophysical

survey

interpretation

Figure 3: Roles of Concerned Staffs and Flow of Well Completion Report Preparation

Among the staffs in charge shown in the above, the staffs directly related to the

update and maintenance of the WID are the Head of Drilling Sectionand the

staffs in the registry room. The Head of Drilling Section is responsible for

supervision of the data entry, maintenance and data analysis while the staffs in

the registry room are responsible for the data entry of the hand written well

completion report.

Output (5) System Analysis Completed

The Drilling Manager has an experience of making a simple borehole inventory

with MS-Excel. Even so he is required to improve the necessary skills for

database maintenance and data analysis such as making tables, creating

formulas and using the aggregate function.

The staffs in the registry room have simple skills to input values in forms in

MS-Word since they have experiences of the data entry of well completion

report to forms in MS-Word. However, they do not have any knowledge and

skills of MS-Excel. Therefore, they need to acquire the skills of MS-Excel for the

data entry in WID.

The technical support from the Contractor and JICA Expert Team in order for

DDC ’s staff to acquire the above skills is described in Section 3.

6: COMPUTER NETWORKING SYSTEM

Three computers will be procured by the Project for the construction of WID.

One computer is used as a server computer while two are used as the client

computers. Each computer is connected by wireless LAN. Total 3 sets of

computers are procured in this project. The specifications of those computers

are almost same. One computer is for server and the others are for clients.

The location to be installed and the usage of each computer are described below.

(1) Server computer

Server computer is installed into the computer room. The staffs in this room

shall be the network administrator. The WID itself is saved in this server. The

backup is done periodically for both server and client computers.

(2) Client computer

One Client computer is installed in the registry room. Update, maintenance

and information retrieval are done in this computer. The staffs in the registry

and the Head of Drilling Section use this computer.

Another Client computer is installed in the Survey Section of Technical Support

Department. Hydrogeologists mainly use it for checking the record of strata

and casing program, and for interpreting the survey result.

DDCA is planning to procure one client computer for browsing the WID to

Technical Manual for Drilling Works for Technical Support Plan for the Drillers in DDCA (2013) - page 3