HomeMy WebLinkAbout2663 - Site Assessment ReportU1ItL
PLANNING DEPARTMENT
REP. NO.
26/63'
MONAGHAN CO. COONCIL
FOR
TERENCE McGARRITY,
DERRYARRIT,
SCOTSTOWN,
CO. MONAGHAN.
MO C. CO.
PLAN U\NG SECTION
08 JUL 2026
APPENDIX A: SITE CHARACTERISATION FORM
File Reference: Terence McGarrity, Derryarrit, Scotstown
Win...;a >_,..ta,�t„i. , 'tom. • • • •• •
Prefix: Mr First Name: Terence Surname: McGarrity
Address: Site Location and Townland:
Derryarrit, Scotstown, Co Monaghan.
Number of Bedrooms: L4 Maximum Number of Residents: I
Comments on population equivalent
There are 4 double bedrooms which will equate to six adults.
Proposed Water Supply:
Mains ® Private Well/Borehole
Soil Type, (Specify Type): Poorly drained mineral soil. Gleys. AminPD
Sandstone and Shale till. TLPSsS
Subsoil, (Specify Type):
Group Well/Borehole
Bedrock Type: DSL
Aquifer Category: Regionally Important I Locally Important LI Poor
Vulnerability: Extreme High Moderate Low Z
Groundwater Body: I Tydavnet Status Good
Name of Public/Group Scheme Water Supply within 1 km: Ai prll s
Source Protection Area: ZOO SI � SO Groundwater Protection Response: R1
Presence of Significant Sites
(Archaeological, Natural & Historical):
Past experience in the area:
None
Raised mounds generally required in this area due to clay subsoil.
Comments: I
(Integrate the information above in order to comment on: the potential suitability of the site, potential targets at risk, and/or any potential site restrictions).
The site is potentially suitable as there appears to be no restrictions to the on -site treatment of domestic effluent. Surface
water and ground water could be targets at risk.
Note: Only information available at the desk study stage snowy oe used III tills secuuti.
3.1 Visual Assessment
Landscape Position:
Elevated on a North -Westerly facing slope.
Slope: Steep (>1:5) Shallow (1:5-1:20) J Relatively Flat (<1:20)
Slope Comment ABOUT 1: 15
Surface Features within a minimum of 250m (Distance To Features Should Be Noted In Metres)
Houses:
Dwelling house along North-Eastern boundary hedge and dwelling house 115m East.
Existing Land Use:
kgricultural grassland.
Vegetation Indicators:
3rass.
Groundwater Flow Direction: Expected North-West
Ground Condition:
Firm during a spell of warm dry weather.
Site Boundaries:
Mature hedges all around.
3.1 Visual Assessment (contd.)
Roads
Local road 68m South -East.
Outcrops (Bedrock And/Or Subsoil):
None
surface vvater ronaing:
\lone
Lakes:
None within 1.5km
Beaches/Shellfish Areas:
None
Wetlands:
None
Karst Features:
None
Watercourses/Streams:"
Straclevan river 324m North-East
"Note and record water level
3.1 Visual Assessment (contd.)
Drainage Ditches:*
No ditch within 60m
Springs:*
None within 100m
Wells:*
None within 100m
Comments:
(Integrate the information above in order to comment on: the potential suitability of the site, potential targets at risk, the suitability of the site to treat the wastewater
and the location of the proposed system within the site).
The site was in good condition underfoot with the assessment being carried out during a spell of dry warm weather.
`Note and record water level
3.2 Trial Hole (should be a minimum of 2.1m deep (3m for regionally important aquifers))
To avoid any accidental damage, a trial hole assessment or percolation tests should not be undertaken
in areas which are at or adjacent to significant sites, (e.g. NHAs, SACs, SPAs, and/or Archaeological
etc.), without prior advice from National Parks and Wildlife Service or the Heritage Service.
Depth of trial hole (m): 2.1
Depth from ground surface Depth from ground surface
to bedrock (m) (if present): to water table (m) (if present): 1.9
Depth of water ingress: I 0.21 Rock type (if present): None
Date and time of excavation: 25 -May -2026 11:30 Date and time of examination: 27 -May -2026 10:00
Depth of
Surface and
Subsurface Soil/Subsoil
Percolation Texture & Plasticity and Soil Density/ Colour**** Preferential
Tests Classification** dilatancy*** Structure Compactness flowpaths
0.1 m
0.2 m UNCOMPACT BROWN GRASS ROOTS
0.3 m
0.4 m
0.5 m
0.6 m
0.7 m UNCOMPACT ORANGE NONE
0.8 m
0.9 m
1.0 m
1.1 m
1.2 m
1.3171 UNCOMPACT GREY NONE
1.4 m
1.5 m
1.6 m
1.7 m
1.8 m
1.9 m
2.0 m
------------------ ----------- -------------------
2.1 m - ----- - ----
2.2 m
2.3 m
2.4 m
2.5 m
2.6 m
2.7 m
2.8 m
2.9 m
3.0 m
3.1 m
3.2 m
3.3 m
3.4 m
3.5 17f
Likely Subsurface Percolation Value: 30
Likely Surface Percolation Value: 40
Note: *Depth of percolation test holes should be indicated on log above. ('Enter Surface or Subsurface at depths as appropriate).
See Appendix E for BS 5930 classification.
"" 3 samples to be tested for each horizon and results should be entered above for each horizon.
All signs of mottling should be recorded.
O
II
IS I
SILT / CLAY
TOP SOIL
3 threads —60mm
ribbons — dilatant
CRUMB
SILT / CLAY subsoil
mottling at 0.7m
5 threads - 110mm
ribbons - dilatant
BLOCKY
O
SS
0
0
SILT / CLAY subsoil
Water table at 1.9m
4 threads - 80mm
ribbons - dilatant
---------------
BLOCKY
------------
I
0
0
0
0
0
Base of trial hole 2.1 m
0
0
0
0
3.2 Trial Hole (contd.) Evaluation:
The trial hole was 2.1 m deep with three distinct layers. Top -soil that was crumb in nature and below that sub -soil that was
orange in colour and blocky in nature with mottling visible around 0.7m. Below that was subsoil that was blocky in nature and
uncompact with 20% cobbles. The water table was at 1.9m.
3.3(a) Subsurface Percolation Test for Subsoil
Step 1: Test Hole Preparation
Percolation Test Hole 1 2 3
Depth from ground surface 400 400 400
to top of hole (mm) (A)
Depth from ground surface 800 800 800
to base of hole (mm) (B) Ii II
Depth of hole (mm) [B - Al 400 400 400
Dimensions of hole 280 x 280 280 x 290 280 x 280
[length x breadth (mm)]
Step 2: Pre -Soaking Test Holes
Pre-soak start Date 25 -May -2026 25 -May -2026 25 -May -2026
Time 15:30 15:30 15:30
2nd pre-soak Date 26 -May -2026 26 -May -2026 26 -May -2026
start Time
10:401 I 10:40 10:40
Each hole should be pre-soaked twice before the test is carried out.
Step 3: Measuring TWO
Percolation Test Hole No. 1 2 3
Date of test 27-05-2026 27-05-2026 27-05-2026
Time filled to 400 mm 10:00 10:00 10:00
Time water level at 300 mm I 11:10 1 11:3011 11:30
Time (min.) to drop 100 mm (T ) 70.00 II 90.00 II 90.00
Average T1
If T1> 480 minutes then Subsurface Percolation value >1 20 — site unsuitable for discharge to ground
If T1 < 210 minutes then go to Step 4;
If 1100> 210 minutes then go to Step 5;
83.33
Step 4: Standard Method (where T100 ≤ 210 minutes)
Percolation
Test Hole
1
2
3
Fill no.
Start Finish At (min)
Start Finish At (min)
Start Finish At (min)
Time Time
Time Time
Time Time
(at 300 (at 200
mm) mm)
(at 300 (at 200
mm) mm)
(at 300 (at 200
mm) mm)
11:10 12:3011 80.00
11:30 13:2011 110.00
11:30 13:3011 120.00
2
12:30 14:5011 140.00
13:20 15:3011 130.00
13:30 15:5511 145.00
3
1 14:50 18:4011 230.00
15:30 19:4011 250.00
15:55 19:5511 240.001
Average At
L150.0]0
163.33
168.33
Value
Average At/4 =
Average At/4 =
Average At/4 =
[Hole No.1] 37.501(t1)
[Hole No.2] 40.831(t2)
[Hole No.3] I 42.081(t3)
Result of Test: Subsurface Percolation Value = 1 40.14 (min/25 mm)
Comments:
he T test was a pass but with some mottling visible below 0.7m I will be recommending a raised mound soil polishing filter.
Step 5: Modified Method (where T100> 210 minutes)
Percolation
Test Hole No.
Percolation
Test Hole No. 2
Fall of water
in hole (mm)
Time
Factor
= T,
Start
Time
hh:mm
Finish
Time
hh:mm
Time
of fall
(mins)
=T
K,s
= T,
/ TT,
T-
Value
= 4.45
/K,s
Fall of water
in hole (mm)
Time
Factor
= T,
Start
Time
hh:mm
Finish
Time
hh:mm
Time
of fall
(mins)
=T
K„
= T,
/ T ,
T—
Value
= 4.45
/K,s
300 - 250
I 8.1 � 0.00 l �
300 - 250
8.1 0.00 ��
250 - 200
9.7 00 0.00 ��
250 - 200
9.7 0.00 �
200 - 150
11.9 =0 0.00 ��
200 - 150
11.9 0.00 ��
150 - 100
14.1 0� 0.00 ��
150 - 100
14.1 0.00 ��
Average
T- Value T- Value Hole 1 = (T1) I 0.001
Average
T- Value T- Value Hole 2 = (12) I 0.001
Result of Test: Subsurface Percolation Value =
Percolation
0.00 (min/25 mm)
Test Hole No.
3
Fall of water
Time
Start
Finish
Time
Ks
T —
in hole (mm)
Factor
Time
Tim§e
of fall
= T,
Value
=T,
hh:mm
hh:mm
(mins)
/T
=4.45
=T
300 -250 I 8.1 lL===J====j10.00 l_10
250 - 200 9.7 0.00 l
200-150 I11.9100 0.00
150- 100 14.1 0.00
Comments:
Average I T- Value T- Value Hole 3 = (T2) 0.00
3.3(b) Surface Percolation Test for Soil
Step 1: Test Hole Preparation
Percolation Test Hole
1 2 3
II I
Depth from ground surface
I
II
1 ii
to top of hole (mrn)
Depth from ground surface
to base hole
400 400 400
of (mm)
Depth of hole (mm)
400 400 400
Dimensions of hole
L__280
x 290 300 x 300 290 X 290
[length x breadth (mm)]
Step 2: Pre -Soaking Test Holes
Pre-soak start Date I 25 -May -2026 25 -May -2026 25 -May -2026
Time 15:35 15:35 15:35
2nd pre-soak Date 26 -May -2026 26 -May -2026 26 -May -2026
start Time 10:45 10:45 10:45
Each hole should be pre-soaked twice before the test is carried out.
Step 3: Measuring T,00
1 2 3
Percolation Test Hole No.
L
27 -May -26 I I
27 -May -26 1 1
27 -May -2026
Date of test
1
1005
10:05
10:05
Time filled to 400 mm
11:05 II
11:10
11:101
Time water level at 300 mm
60.00
65.00
65.00
Time to drop 100 mm (T,00)
63.33
Average T,0o
If T,OO > 480 minutes then Surface Percolation value >90 - site unsuitable for discharge to ground
If T100 ≤ 210 minutes then go to Step 4;
If T100 > 210 minutes then go to Step 5;
Step 4: Standard Method (where T100 ≤ 210 minutes)
Percolation
Test Hole
1
2
3
Fill no.
Start Finish AT (min)
Start Finish AT (min)
Start Finish AT (min)
Time Time
Time Time
Time Time
(at 300 (at 200
(at 300 (at 200
(at 300 (at 200
mm) mm)
mm) mm)
mm) mm)
1
11:051111:5511 50.00
11:101112:101160.001
I 110511 122011 75.00
2
I 11:55 13:3011 95.00
12:10 13:5511 105.00
12:20 14:1011 110.00
3
13:301116:1011160.00
13:551116:4011 165.00
14:10 17:2011190.00
Average AT
101.67
125.00
110.00
Value
Average AT/4 =
[Hole No.1] 25.42](T)
Average AT/4 =___________
[Hole No.2] I 27.501(12)
Average AT/4 =
[Hole No.3] I 31.251(T3'
Result of Test: Surface Percolation Value = 28.06 (min/25 mm)
Comments:
fhe topsoil at this site is of good quality and may be used to form a raised mound soil percolation area to polish treated effluent from an
advanced treatment system.
Step 5: Modified Method (where T100> 210 minutes)
Percolation
Percolation
Test Hole No.
1 Test Hole No.
2
Fall of water
Time
Start
Finish
Time
Ks
T -
Fall of water
Time
Start
Finish
Time
Ks
T -
in hole (mm)
Factor
Time
Time
of fall
= T,
Value
in hole (mm)
Factor
Time
Time
of fall
= T,
Value
= T,
hh:mm
hh:mm
(mins)
/ T
= 4.45
= T,
hh:mm
hh:mm
(mins)
IT
= 4.45
/K=
300 - 250
8.1
�0
0.00
��
300 - 250
8.1
0.0011
250 - 200
9.7
00
0.00
��
250 - 200
9.7
00
0.00
��
200 - 150
11.9
�0
0.0011�
200 - 150
11.9
0.00I=�
150- 100
14,1
�0
0.0011�
150 - 100
14.1
0�
0.0011�
Average I T- Value
Percolation
Test Hole No. 3
T- Value Hole 1 = (T1) o.00l
Average I T- Value T- Value Hole 2 = (Tz) 0.00
Result of Test: Surface Percolation Value =
0.00 (min/25 mm;
Fall of water Time Start Finish Time K,. T - Comments:
in hole (mm) Factor Time Time of fall = T, Value
= T, hh:mm hh:mm (mins) / T = 4.45
IK,s
300 -250 I 8.1 0.00 �
250-200F_9.7][ 0 0.00 ��
200-150 11.9 00 0.00 ��
150-100 14.1 �� 0.0011�
Average T- Value T- Value Hole 3 = (T2) I 0.00
Integrate the information from the desk study and on -site assessment (i.e. visual assessment, trial hole and
percolation tests) above and conclude the type of system(s) that is (are) appropriate. This information is also used
to choose the optimum final disposal route of the treated wastewater.
Slope of proposed infiltration / treatment area: 1:15
Are all minimum separation distances met? //
Depth of unsaturated soil and/or subsoil beneath invert of gravel
(or drip tubing in the case of drip dispersal system) 0.90
Percolation test result: Surface: 28.06
Not Suitable for Development I
Identify all suitable options
Septic tank system (septic tank and
percolation area) (Chapter 7)
2. Secondary Treatment System
(Chapters 8 and 9) and soil polishing filter
(Section 10.1)
Tertiary Treatment System and Infiltration /
treatment area (Section 10.2)
No
Yes
Yes
Sub -surface: P 40.14
Suitable for Development I /
Discharge Route'
Groundwater
Propose to install: Secondary Treatment System and soil polishing filter
and discharge to: Ground Water 0
Invert level of the trench/bed gravel or drip tubing (m) I 0.601
Site Specific Conditions (e.g. special works, site improvement works testing etc.
Mechanical aeration system and a raised mound soil polishing filter measuring 1.0m in height to be installed and constructed
to EPA 2021 specifications. The raised mound shall be made up of the insitu topsoil and is required as there was some
evidence of mottling below 0.7m. I recommend 60m of percolation trench in the soil polishing filter consisting of 6 lengths of
trench each measuring 1 Om. The invert of the percolation trenches should be at 0.6m with 0.9m pervious unsaturated soil
below to ensure proper polishing of the final effluent. The raised percolation area shall measure 13m x 15m and may be
landscaped into the contours of the site. Ensure that the final effluent from the mechanical aeration system is distributed
evenly to each of the six percolation trenches. It is important to ensure that the percolation trenches and related pipe work are
put in at the correct slope. A surface water drain measuring 1 m deep shall be employed (min 2m away) up -slope from the
raised mound soil polishing filter to divert surface water away from the percolation area and to prevent the water table rising in
wet weather.
NOTE: It is very important to ensure that the aeration pump remains on at all times on the mechanical aeration system or
otherwise the system will revert to septic conditions causing odors and poorer quality effluent which may lead to clogging of
the percolation trenches.
' A discharge of sewage effluent to "waters" (definition includes any or any part of any river, stream, lake, canal, reservoir, aquifer, pond, watercourse or other
inland waters, whether natural or artificial) will require a licence under the Water Pollution Acts 1977-90. Refer to Section 2.4,
SYSTEM TYPE: Septic Tank Systems (Chapter 7)
Tank Capacity (m3) Percolation Area
Mounded Percolation Area
No. of Trenches
�__________ No. of Trenches 6.00
Length of Trenches (m)
Length of Trenches (m) 1 10.00
Invert Level (m)
Invert Level (m) I 0.601
SYSTEM TYPE: Secondary Treatment System (Chapters
8 and 9) and polishing filter (Section 10.1)
Secondary Treatment Systems receiving septic tank effluent Packaged Secondary
(Chapter 8)
Treatment Systems
receiving raw wastewater
(Chapter 9)
Media Type Area (m2)* Depth of Filter
Invert Level Type
Sand/Soil
BAF TREATMENT SYSTEM
Soil _____________
1 Capacity PE 16
Constructed Wetland
Sizing of Primary Compartment
Other
2.90 m3
Polishing Filter*: (Section 10.1)
Surface Area (m2)* 30.00
Option 3 - Gravity Discharge 60.00
Trench length (m)
Option 1 - Direct Discharge
Surface area (m2) II
Option 4 Low Pressure
Pipe Distribution
Option 2 - Pumped Discharge
Trench length (m)
Surface area (m2) 0
Option 5 - Drip Dispersal
Surface area (m2)
SYSTEM TYPE: Tertiary Treatment System and infiltration
/ treatment area (Section 10.2)
Identify purpose of tertiary Provide performance information Provide design information
treatment demonstrating system
will provide
required treatment
levels
DISCHARGE ROUTE:
Groundwater ❑✓ Hydraulic Loading Rate * (l/m2.d)
30.00 Surface area (m2) 30.00
Surface Water ** Discharge Rate (m3/hr)
I 0.041
* Hydraulic loading rate is determined by the percolation rate of subsoil
** Water Pollution Act discharge licence required
QUALITY ASSURANCE:
Installation & Commissioning
System to be signed off by a suitably qualified person and recommendations in section 5.0 to be adhered to. Package
treatment system must conform to EN 12566-3 standard. Package treatment system to be properly installed and certified by
company supplying the system in accordance with the EPA 2021 code of practice. Keep records of desludging for five years.
On -going Maintenance
Desludge tank as recommended by manufacturer and periodically inspect the system for damage or surface ponding.
Maintenance contract to be agreed by company supplying the package treatment system and contract must be adhered to so
as to ensure that the system continues to function property.
Company: IBiolabs
Prefix: Mr Q First Name: Fel Surname: Holohan
Address:
ITERERA, SCOTSTOWN, CO. MONAGHAN
Qualifications/Experience: IGSI / EPA CERTIFIED
Date of Report: 28 -May -2025
Phone: 08681691621 E-mail IbiolabsirI@outtook.com
Indemnity Insurance Number: API0002262
UPiFIT!LII...I.I
WELLS AND BOREHOLES ADJACENT TO THE SITE
, U Public Supply Source Protection Areas
SI-Inner Protection Area
SO -Outer Protection Area
i
•
1T�
SOURCE PROTECTION DATA (N/A) fl
0
VULNERABILITY LOW
BEDROCK DSL
• K1 b7c aCt1l liQrt '--
L.. Derr n ran.
Der
/ 57
illa7� LU fSesklPL • 'rCarbionog
Skeatry B
- . — �• �-.- . ��Kai �
VI/ st • Triyc
Derryarr't� ••
Dundrumman -
Golip Irish - rYif- - GOIa
Drumman:�
• r
mu lagh 80 Druml
cup tough
¶Derrylccdigan _ '�� 1
.Y 1 Drdloo .
Shanroe •
_ X Agtlallssabeag• Alia es
,'
4
A
AERIAL \4EW OF PERCOLATION SITE
TN
DLip tCl cT
NpuSE
I
� Vv Ec.0 A G
SKETCH OF PERCOLATION AREA INCLUDING SITE SURROUNDS
744-
_
rr ,
b nl
rq
-aye •
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f . �$ F^_i . Rr'LQ� ., t.;'�t�. eta ! �: � � '• +
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l t
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P S t s�q�,' `'�'' F
TRIAL HOLE ON DAY OF EXCAVATION
tt
•.h Tat ! � _h� Y � ! 1' . ',�i+��K � �.��.�1,� t'. V
71
t mSi
;
I
TRIAL HOLE TWO DAYS AFTER EXCAVATION
Ti
T2
T3
• 4�,yc t / t lip• ?
T TEST HOLES
P1
P2
P3
P TEST HOLES
OUTLINE SPECIFICATIONS FOR MOUNDED SOIL POLISHING FILTER
1. Treated effluent from the mechanical aeration sump unit shall be pumped
Intermittently, or fed by gravity if the levels allow, to the distribution chamber
on the mound feeding the 6 percolation trenches. The raised mound shall be
1.0m in height throughout its area and consist of the topsoil from the site. The
mound shall measure 13m x 15m and may be landscaped into the contours of
the site.
2. The slope of the percolation trenches from the distribution chamber shall be 1
in 200.
3. The length of each of the 6 percolation trenches shall be 10m. Total length
60m.
4. The separation distance between the percolation trenches shall be 2m (ie
2.5m centre to centre)
5. Percolation pipes shall be 100mm diameter smooth wall uPVC sewer pipes,
perforated at 4, 6 and 8 o'clock. Perforations shall be 8mm diameter, at
75mm centre's along the pipe. Holes shall be checked before installation to
ensure they are free from debris.
6. The width of each percolation trench shall be 500mm.
7. The depth of each percolation trench shall be 600mm below the mound
surface.
8. Percolation pipes shall be laid on a 250mm bed of washed gravel, having
particles in the range of 8 - 32mm.
9. Pipe surround shall be washed gravel, having particle size in the range 8 -
32mm.
10. Pipe cover shall be 150mm depth of washed gravel, having particle size in
the range of 8 - 32mm.
11. Geotextile layer to be placed on top of this followed by 100mm topsoil to
top of mound.
12. Geotextile shall be in accordance with EN ISO 10319.
Access / inspection points and vents shall be provided for the ends of the
percolation pipes. Covers shall be visible and installed to prevent the
ingress of water. They shall be suitable for rodding and scouring purposes.
13. A surface land drain 1m deep shall be employed all around the raised mound
soil polishing filter and not closer than 2m to divert surface water away
from it and to prevent the water table rising in this area.
SCHEDULE OF SITE SEPARATION DISTANCES
PACKAGE TREATMENT SYSTEM
. Minimum distance to any dwelling = 7m
. Minimum distance to site boundary = 3m
. Minimum distance to trees = 3m
. Minimum distance to roads = 4m
. Minimum distance to slope breaks = 10m
. Minimum distance to watercourse / streams = 10m
. Minimum distance to soakaway = 10m
. Minimum distance to open drain = 10m
. Minimum distance to lake or foreshore = 50m
ble 6.3 EPA Code of Practice 2021
POLISHING FILTER
. Minimum distance to any dwelling = 10m
. Minimum distance to site boundary = 3m
. Minimum distance to trees = 3m
. Minimum distance to roads = 4m
. Minimum distance to slope breaks = 10m
. Minimum distance to water course / stream = 10m
Minimum distance to soakaway = 10m
Minimum distance to open drain = 10m
Minimum distance to lake or foreshore = 50m
. Minimum distance to up gradient well = 15m
. Minimum distance well on same level = 30m
. Minimum distance to down gradient well = 40m
ble 6.1 EPA Code of Practice 2021 unless stated otherwise
TOPSOIL
100MM MOUNDED TOPSOIL I .OM
GEOTEXTILE LAYER 150MM WASHED
STONE ABOVE PIPE
O 100MM PIPE 0.6M
250MM WASHED
STONE BELOW PIPE
INVERT OF TRENCH
SUITABLE SUBSOIL GROUND LEVEL
MINIMUM 0.9M
Water table
EACH TRENCH 500MM WIDE
SECTION THROUGH MOUNDED SUBSOIL PERCOLATION SYSTEM