The limit of 460 gm/m3 soil, is (assuming a soil bulk density of
about 1) equivalent to a MAF soil Na reading of about 20. Thus, while some
elevated soil Na levels were recorded during the disposal process the current
levels (0-75 mm) are normal (Table 2). This is also apparent in the SAR levels.
The likely reason for this is that Na (and the same applies to chloride) are very
mobile and will readily leach out of soils, especially sandy soils with a good
rainfall and under irrigation, noting
pathological micro-organisms. Usually expressed as colony forming
units per 100 millilitre sample
fresh elevated flow in a stream, such as after heavy rainfall
g/m3 grams per cubic metre, and equivalent to milligrams per litre (mg/L). In
water, this is also equivalent to parts per million (ppm), but the same
does not apply to gaseous mixtures
Incident an event that is alleged or is found to have occurred that may have actual
or potential environmental consequences or may involve
failure of the pumps and warning alarms. Heavy rain on 15 December 2021
resulted in the Hector Place pump station overflowing to the Tasman Sea for approximately nine hours.
Overflows from Hector Place also occurred on 6 and 13 February 2022 as a result of very heavy rainfall
(Cyclone Dovi).
Environmental effects of exercise of consents
Monitoring of system performance indicated that a high standard of effluent quality was produced by the
oxidation pond and series of two wetlands.
inspection.
30 June 2022
During this inspection, no runoff was observed offsite or past bunded areas. There was some ponding of
water beneath pig pens, with recent heavy rainfall likely a contributing factor. The methane generator was
not running at time of inspection and the methane pit was half full with some water present atop cover.
Odour was localised to immediate vicinity of piggery. The effluent ponds were full but not discharging to
the stream. Compliance at time of inspection.
the composting process in the initial phase.
Any rainfall runoff and leachate that is generated on pad 3, drains into a series of ponds for treatment
referred to as the pond treatment system (PTS). Between each pond is a baffle that skims off any floating
hydrocarbons as the leachate passes through. These ponds also treat the leachate and stormwater from pad
1 where greenwaste and sheep skin is routinely composted. The treated liquid from PTS is then irrigated to
cut and carry pasture on
both camps during the period
under review. NPDC remain under abatement notice at both camps to comply with their consent conditions.
Exceedances of discharge limits occur intermittently as a result of high rainfall and groundwater infiltration
into the wastewater networks. Exceedances during peak holiday periods are also influenced by higher camp
occupancy and the increased wastewater volumes generated. Both consents are currently in the process of
being renewed. Solutions to the current
this recognised ecosystem had been taken into account in the setting of
buffer distances and location of the stockpiling facilities.
The predominant soil type has been identified as gravelly sand and vegetation growth consists of native
bush which transitions into pasture. Average annual rainfall for the site is 1,942 mm (taken from the nearby
‘Stratford’ monitoring station).
The stockpiling facility located at Surrey Road is operated under one consent (7559-1.4). This consent allows
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
Te
m
p
D
iff
er
en
ce
Consent Limit (1.5 oC for 95% of time)Consent Limit (1.5 oC for 95% of time)
Patea at East Rd d/s minus u/s
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18
2.1.4.2 Discharges to the Kahouri Stream
The Company recorded 28 occasions where stormwater was discharged to the Kahouri Stream during the
2022-2023 monitoring period. These discharges occurred during high rainfall events. Stormwater
monitoring is
Application attachment appendix E Natural Character Landscape Manawa Energy 14 Feb 2023
and associated actions to minimise or prevent damage by floods and river erosion.
In 2018/2019, all flood control schemes will be maintained to the 1 in 100 year levels of protection or to the
standard set in the relevant asset management plan for minor schemes. Rainfall and river levels will be
monitored and timely flood warnings issued.
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21
Recreation, culture and heritage
Facilitate the continued development and maintenance of Yarrow