HomeMy WebLinkAbout2678 - Site Assessment ReportFOR
KEVIN O'HAGAN,
DERRYRELLAN,
KILLYBRONE,
CO MONAGHAN.
PlX(�ZN DEPAF�i N�
\ttF.N
PLANN NN FCTI N
19 AUG 2n2r
ONAGH \N QQ. C NCIL
N. CO.
PLAN ING 5 TION
REG.
PLANK NG ®i:.PARTMViEY-`j
PER NO.
N926/7o -
MONAGHAN CO. COI_UN .
APPENDIX A: SITE CHARACTERISATION FORM
File Reference: Kevin O'Hagan, Cavan Moutry, Emyvale.
Prefix: Mr S First Name: Kevin Surname: O'Hagan
Address: Site Location and Townland:
rlornirAlinn Killvhrnna rxn-AAnnnnhnn Derryrellan, Killybrone, Co -Monaghan.
Number of Bedrooms: Maximum Number of ResiOpnts: 6
Comments on population equivalent ON. CC
There are 4 double bedrooms which will equate to six adults. NING S
4 v'L 2026
Proposed Water Supply:
RE . NO
Mains Private Well/Borehole
Soil Type, (Specify Type):
Poorly drained mineral soil. Gleys. AminPD
Sandstone and shale till TLCSsS
Subsoil, (Specify Type):
N
Group Nell/Borehole O
Bedrock Type: DMSSL
Aquifer Category: Regionally Important Loc ly�tfL 4 Lm 0 Poor El
Vulnerability: Extreme High Moderate wlv
L~ IRAR%
Groundwater Body: Aughnacloy Status Poor'`
Name of Public/Group Scheme Water Supply within 1 km: ITruce l C
Source Protection Area: ZOO ❑ SI SO Groundwater Protec i"' 5� R1
Presence of Significant Sites
(Archaeological, Natural & Historical): None
Past experience in the area: Raised mounds gererally required in this area.
Comments:
(Integrate the information above in order to comment on: the potential suitability of the ite, p jntigl taggets at risk, and/o ally potential sine restrictions).
U'U V.. -., '. .,�•, it
The site is potentially suitable as there appears to be no restrictions t the on -site treatment of domestic'efflueht. Surface
water and ground water could be targets at risk. + 9 A�7,�',i I
Note: Only information available at the desk study stage should he used in this section.
3.1 Visual Assessment
Landscape Position: Low-lying near base of North -Easterly facing slope.
Slope: Steep (>1:5) Shallow (1:5-1:20) Relatively Flat (<1:20)
Slope Comment About 1:18
Surface Features within a minimum of 250rn (Distance To Features Should Be Noted In Metres)
Houses:
Dwelling house 55m East North-East, 99m North North-West and 102m North-West.
Existing Land Use:
Agricultural grassland.
Vegetation Indicators:
Grass
Groundwater Flow Direction: Expected North-East.
Ground Condition:
Firm during a spell of wet weather.
Site Boundaries:
Mature hedges all around.
3.1 Visual Assessment (contd.)
Roads:
Local road along the North-Eastern boundary hedge.
Outcrops (Bedrock And/Or Subsoil):
None
Surface Water Ponding:
None
Lakes:
Lough More 3.2km South -East.
Beaches/Shellfish Areas:
None
Wetlands:
None
Karst Features:
None
Watercourses/Streams:"
Rakelly river 282m South -East.
*Note and record water level
3.1 Visual Assessment (contd.)
Drainage Ditches:'
Open ditch along North-East boundary hedge. 1 m deep containing 0.2m water
Springs:*
None listed within 100m
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 period of wet 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): J to water table (m) (if present): 1.3
Depth of water ingress: I 0.8j Rock type (if present): None
Date and time of excavation: 08 -Jun -2026 II 12:301 Date and time of examination: 10 -Jun -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 II
0.2m I
0.3 m I
0.4 m 0
0.5m 0
0.6m1 I
0.7 m II
0.8m tS
0.9m I
1.0 m I
1.im l__ I
1.2 m
1.3m1
1.4 m II
1.5m II
1.6m �]
1.7 m I
1.8m II
1.9m 0
2.0m 0
2.1 m II
2.2m 0
2.3 m
2.4 m
2.5 m I
2.6m 0
2.7m 1I
2.8m1
2.9 m
3.0 m
3.lm[
3.2 m
3.3 m
3.4 m
3.5 m
I
SILT / CLAY 3 threads —70mm
TOP SOIL ribbons — dilatant
5 threads -110mm
SILT / CLAY subsoil ribbons - dilates
50% clay with difficulty.
Water table 1.3m
Base of trial hole 2.1 m
�
0
Likely Subsurface Percolation Value: I 401
Likely Surface Percolation Value: I 30
CRUMB
BLOCKY
SOFT
UNCOMPACT
BROWN GRASS ROOTS
NONE
PALE
BROWN
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.
.... Ail signs of mottling should be recorded.
3.2 Trial Hole (contd.) Evaluation:
The trial hole was 2.1 m deep. There were two distinct layers. Silt / clay top -soil and below that sub -soil that was blocky in
nature with about 40% clay. The water table was at 1.3m
3.3(a) Subsurface Percolation Test for Subsoil
Step 1: Test Hole Preparation
Percolation Test Hole
3
Depth from ground surface
40011
40011400
to top of hole (mm) (A)ii
II
Depth from ground surface
80011
Ii
80011
I
8001
to base of hole (mm) (B)
II
II
Depth of hole (mm) [B - A]
400
r
400
400
Dimensions of hole
270 x
310
280 x
300
290 x 280
[length x breadth (mm)]
Step 2: Pre -Soaking Test Holes
Pre-soak start Date
08 -Jun -2026 I
08 -Jun -2026
08 -Jun -2026
Time
16:301
I 16:301
I 16:30
2nd pre-soak Date
09 -Jun -2026
09 -Jun -2026
09 -Jun -2026
start Time
15:00
15:00
15:00
Each hole should be pre-soaked twice before the test is carried out.
Step 3: Measuring 1100
Percolation Test Hole No.
1
2
3
Date of test
10-06-2026 II
10-06-202611
10-06-2026
Time filled to 400 mm
10:00
10:00
10:001
Time water level at 300 mm
I 13:20
13:3011
13:401
Time (min,) to drop 100 mm (T100)
I 200.0011
210.0011
220.001
Average T100
210.00
If T100 > 480 minutes then Subsurface Percolation value >120 — 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 T,00 < 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
1I II o.00j
I
II 0.00l
II 0.00
2
I 1 0.001
I II II 0.001
II II 0.00
3
1l II 0.001
II
II 0.00
0.00
Average At
0.00
=0-00
0.00
Value
Average At/4 = Average At/4 = Average At/4 =
[Hole No.1] I 0.001(t1) [Hole No.2]
T 0.001(t2) [Hole No.3] 0.001(t3)
Result of Test:
Subsurface Percolation Value = 0.00 (min/25 mm)
Comments:
With the sub -surface
tests being slow I proceded to step 5
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 K,, T-
Fall of water Time Start Finish Time K„ 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) / T , = 4.45
=T /K„
=1 /K,,
300-250
I 8.1 13:20 14:20 60.0Q11 0.1411 32.96
300 - 250 8.1 13:30 14:50 80.00ll 0.10 43.95
250-200
I 14:20 15.40 80.0011 0.12 36.70
250-200 Ig7 14:50 16:00 70.0011 0.1411 32.11
200 - 150
11.9 15:40 17:55 135.00 0.09 50.48
200 - 150 I 11.9 16:00 I 18:00 120.00 0.10 44.87
150- 100
14.1 17:55 20:40 165.00 0.09 52.07
150 - 100 I 14.1 18:00 I 21:10 190.00 0.07 59.96
Average
T- Value T- Value Hole 1 = (T) 3.06l
Average T- Value T- Value Hole 2 = (T2) 45.23
Result of Test: Subsurface Percolation Value =
Percolation
45.271 (min/25 mm)
Test Hole No.
3
Fall of water
Time Start Finish Time K„ T—
Comments:
in hole (mm)
Factor Time Tim§e of fall = T, Value
= T, hh:mm hh:mm (mins) /T,, = 4.45
A raised mound will be required due to the amount of clay
in the subsoil.
300-250
8.1 13:40 15:10 90.00 0.09 49.44
250 - 200
Ig7 15:10 I 16:20 70.0011_0.1411_32.11
200 - 150
11.9 16:20 18:30 130.0011_0.0911_48.61
150-100
I 14.1 18:30121:40 190.00 0.07 59.96
Average
T- Value T- Value Hole 3 = (T2) 47.53
3.3(b) Surface Percolation Test for Soil
Step 1: Test Hole Preparation
Percolation Test Hole 1 2 3
Depth from ground surface
to top of hole (mm)
Depth from ground surface I 40011 40011 400
to base of hole (mm)
Depth of hole (mm) 400 400 400
Dimensions of hole
[length x breadth (mm)] I
290 x 280 280 x 280 290 x 270
Step 2: Pre -Soaking Test Holes
Pre-soak start Date
Time
2nd pre-soak Date
start Time
08 -Jun -2026
16:35
09 -Jun -2026
15:05
08 -Jun -2026
16:35
09 -Jun -2026
15:05
Each hole should be pre-soaked twice before the test is carried out.
Step 3: Measuring T100
1 2 3
Percolation Test Hole No.
I II II I
10 -Jun -26 H 10 -Jun -26 10 -Jun -2026
Date of test
Time filled to 400 mm 10:05 10:05 10:05
Time water level at 300 mm 11:15 1110 11:15
70.00 65.00 70.00
Time to drop 100 mm (T,00)
e 68.33
Average T100
08 -Jun -2026
16:35
09 -Jun -2026
15:05
If T1 > 480 minutes then Surface Percolation value >90 - site unsuitable for discharge to ground
If T1 ≤ 210 minutes then go to Step 4;
If T100 > 210 minutes then go to Step 5;
Step 4: Standard Method (where T,00 ≤ 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)
1I
ijj 12:4011 85.00
11:10 12:2511 75.00
11:1511 12:45 90.00
2
12:40 14:3011 110.001
I 12j 14:2011 115.00
12:45[14:4011 115.00
3
Average AT
14:30 17:4011 190.00
14:20 17:2011180.00114:40
123.33
17:45 185.00
130.00
128.33
Value
Average AT/4 =
[Hole No.1] 32.081(T1)
Average AT/4 =___________
[Hole No.2] j 30.83 (T2)
Average AT/4 =
[Hole No.3] I 32.501(T3
Result of Test: Surface Percolation Value = 31.81 (min/25 mm)
Comments:
'he topsoil at this site is of fair 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 T,oa > 210 minutes)
Percolation
Test Hole No. 1
Fall of water Time Start Finish Time K. T -
in hole (mm) Factor Time Time of fall = T, Value
= T, hh:mm hh:mm (mins) / T,, = 4.45
=L /K.
300 - 250 8.1 I 0.00 =1
250 - 200 9.7 00 0.00 ��
200- 150I11.911� 0.0011�
150- 100 14.1 �� 0.00 ��
Average I T- Value
Percolation
Test Hole No. 3
T- Value Hole 1 = (Ti) I 0.00
Fall of water Time Start Finish Time K,, T-
in hole (mm) Factor Time Time of fall = T, Value
= T, hh:mm hh:mm (mins) / T,� = 4.45
=L /K,,
300 - 250 I 8.1 0.00 l �
250 - 200 9.7 =0 0.00 �
�______
200-150 � 11.9 = 0.00
150-100 � 14.1 == 0.00 �
Average I T- Value T- Value Hole 3 = (T2) 0.00
Percolation
Test Hole No. 2
Fall of water
Time
Start
Finish
Time
K,,
T —
in hole (mm)
Factor
Time
Time
of fall
= T,
Value
= T,
hh:mm
hh:mm
(mans)
/ T
= 4.45
= m
/K„
300 - 250
8.1
0=
0.0011
250 -200
9.7
00
0.00
l
_____
200-150
11.9
_=
150-100
14.1
=
0.00
�
�
Average I T- Value T- Value Hole 2 = (T2) 0.00
Result of Test: Surface Percolation Value =
o.00 (min/25 mm)
Comments:
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: I 1:18
Are all minimum separation distances met?
Depth of unsaturated soil and/or subsoil beneath invert of gravel
.90
(or drip tubing in the case of drip dispersal system)
Percolation test result: Surface: 31.81
Not Suitable for Development
Identify all suitable options
Septic tank system (septic tank and
percolation area) (Chapter 7)
Secondary Treatment System
(Chapters 8 and 9) and soil polishing filter
(Section 10.1)
No
Yes
3. Tertiary Treatment System and Infiltration /
Yes
treatment area (Section 10.2)
Sub -surface: 45.27
Suitable for Development ✓0
Discharge Route'
Groundwater
Propose to install: Secondary Treatment System and soil polishing filter
and discharge to: Ground Water jj
Q
Invert level of the trench/bed gravel or drip tubing (m) 0.60
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 is required due to the high clay content in the subsoil. The raised mound shall
be made up of the insitu topsoil. 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 13m 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)
I
Tank Capacity (m') Percolation Area
Mounded Percolation Area
No. of Trenches
No. of Trenches 6.00
Length of Trenches (m)
Length of Trenches (m) r 10.00
Invert Level (m)
Invert Level (m) 0.60
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 I
Capacity PE 16
Constructed Wetland i P
Sizing of Primary Compartment
Other
2.901 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)
Option 4 - Low Pressure
Pipe Distribution
Option 2 - Pumped Discharge
Trench length (m)
Surface area (n -t2) 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 .* (I/m2.d)
I 30.001 Surface area (m2) I 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 properly.
Company: lBio1ab8 I
Prefix: Mr 0 First Name: Michael j Surname: IHolohan
Address:
ITERERA, SCOTSTOWN, CO. MONAGHAN
Qualifications/Experience: IG51 / EPA CERTIFIED
Date of Report: 12 -Jun -2026
Phone: 0868169162 E-mail biolabsirl@outlook.com
Indemnity Insurance Number: I _ RPI-IE000946-00
�Jj Signature: _ ___.4-!`! _ _
VULNERABILI1[V V,OMV
BEDROCK DMSSL
C)
WELLS AND BOREHOLES ADJACENT TO THE SITE
LJ Public Supply Source Protection Areas
SI-Inner Protection Area
SO -Outer Protection Area
SOURCE PROTECTION DATA (N/A)
RIVERS AND LAKES
AQUIFER CATEGORY Lm
a,
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AERIAL VIE\A/ OF PERCOLMHON Sh E
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PELCI
C�D�7v Loc=11L
SKETCH OF PERCOLATION AREA INCLUDING SITE SURROUNDS
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r:
sil `5-►, t♦�y
k
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`J�tiiGi ?n�rfy ; N y 3 a
VIEWS OF PERCOLATION SITE
TRIAL HOLE ON DAY OF EXCAVATION
i a,
TRIAL HOLE TWO DAYS AFTER EXCAVATION
`(ti�``���e:�`..•..�.' _ ,��� 'r" �,� Y ?'�` - ..- 'r;�„i4�YN �f^ � / �•.�y�_ ' z j . r�v� n'� it ,Yj „ _'�'.� _'
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147#+2; . -
►•., 4.'� ry'
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�[ a q ,
s,T,
K
ji�r:'.
r„Ie qt' r t.
T TEST HOLES
T3
P1
f �� _x '� �jr •�C'� _'C f.
P TEST HOLES
P2
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 13m.
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 upslope of the raised mound
soil polishing filter and not closer than 2m to divert surface water away
from it and stop the water table rising in wet weather.
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
able 6.31 EPA Code of Practice 2021 unless stated otherwise
GEOTEXTILE LAYER
TOPSOIL
100MM
150MM WASHED
STONE ABOVE PIPE
O 100MM PIPE
250MM WASHED
STONE BELOW PIPE
SUITABLE SUBSOIL
MINIMUM 0.9M
Water table
EACH TRENCH 500MM WIDE
0.6M
INVERT OF TRENCH
MOUNDED TOPSOIL I.0M
GROUND LEVEL
SECTION THROUGH MOUNDED SUBSOIL PERCOLATION SYSTEM