Management of waste and bulk materials

A short distance to the vacuum waste collection system and recycling rooms make it easier for residents in Stockholm Royal Seaport to sort their waste correctly.

During the construction process, priority is given to local soil remediation, and reuse of excavated soil and rock. All construction waste should be sorted and where possible minimized.

Soil remediation, bulk materials management and construction waste for public spaces

Stockholm Royal Seaport is an old industrial site with large areas that need to be remediated. The remediation is performed in line with site-specific benchmarks in accordance with guidelines and methodology of the Swedish Environmental Protection Agency.

Priority is given to local soil remediation, and reuse of excavated materials on site. In 2018, large amounts of excavated materials did not meet the quality requirements, hence the mass balance was lower than previous years.

The excavated materials that does not meet the quality requirements is transported offsite for remediation or final disposal, see pie chart 3.1. below. To date the remediated surface amounts to a total of 321,610 m², which corresponds to 45 soccer fields.

All contractors sort their construction waste, and the majority goes to recycling, see Figure 3.1.

Dewatering of groundwater occurs when excavation take place below the groundwater table, in these cases water needs to be pumped and treated before discharged to Lilla Värtan .In 2018, 2,750 m³ of water was treated in the local water purification plant and discharged, this corresponds to a Olympic swimming pool.

Contractor requirements:

100% of construction waste should be sorted
Construction waste to landfill should be minimized
Mass balance should be achieved

Table 3.1 Overview of soil remediation areas, mass balance, construction waste and drainage water in public space

Etapp/xx	GK4	Brofästet	Norra 2	Västra	Norra 1
	Totalt	2018	2017	2016	Tom 2015
Area remediated, m²	321 610	39 410	18 200	26 400*	IU
Area remediated to date, %	25%	25%	22%	21%	IU
Excavated material, tonnes	2 000 000	136 360	49 240	355 800	1 440 000
Mass balance, reuse of materials, tonnes	775 000	17 560	13 840	136 870	600 000
Renat länsvatten, m³	IU	2 750	8 200	26 450	17 600*

*Area remediated from 2016.

* March-December 2015.

Diagram 3.1 Construction waste and disposal in %, public space

Kommentar:

The waste from constructing public spaces is in general evenly distributed between energy recovery and material recycling. Concrete, metal, and scrap is material recycled, while wood and combustible material is sent to energy recovery.
In 2017-2018, the Stockholm Royal Seaport sent 1,800 tonnes of metal from the demolition of Gasklockan 4 to material recycling. This caused the recycling fraction to be larger than previous years. Stockholm City was responsible for the demolition of the Gasklockan, therefore the statistics is reported for public space. However, the site will be developed as a development site by a developer.
The demolition waste from Gasklockan 4 also included 371 tonnes of hazardous waste sent to landfill, as it contained contaminated material and soil from the industrial gas production.

Household and construction waste on development sites (buildings)

Requirement maximum distance from door to sorting:

Properties are connected to the vacuum waste system, with a maximum distance of 30 meters from building entrance to the waste disposal
Kitchen grinders are installed.
Recycling rooms for other waste fractions to be located a maximum distance of 50 metres from the building entrance
No requirements were placed on Norra 1 and Västra

The average distance between the building entrances and a refuse chute is 29 metres, and 33 meters to the recycling room. Non-compliances have been reported for a small number of stairwells, and for urban townhouses, these were approved due to the neighbourhood’s design, and to facilitate waste removal. The recycling rooms are in most cases easily accessible The size of these rooms in Norra 2 is on average 0.42 m² per apartment, and for Brofästet 0.44 m² per apartment. See table 3.2. below.

The vacuum waste collection system, in combination with kitchen grinders, reduces both the amount of waste and the number of waste transports in the area. Residual waste collected by the vacuum system amounts to 212.6 kg/residence, compared to the 520 kg/residence Swedish average, according to Waste Sweden (Avfall Sverige).

None of the property developers complied with the requirement on construction waste (20 kg/m² GFA), on average this resulted in 39 kg/m² GFA. The property developers have not been sufficiently proactive in preventing and reducing the amount of construction waste. Deficiencies in quality assurance processes during the construction stage have contributed to damp materials that had to be disposed of. The evaluation has led to changing the requirement, that all future property developers will submit a waste management plan describing how they will achieve the 20 kg/m² GFA target.

Requirements for building construction waste :

20 kg/m²GFA
100 weight procent of all construction waste is to be sorted, of which maximum 5% of the weight can go to landfill
Contractors are to follow the waste hierarchy
There are only voluntary commitments for Norra 1 och Västra

Table 3.2 Amount of waste in the vacuum waste collection system, distance to the vacuum waste collection system, recycling rooms and construction waste per phase

Etapp/xx Norra 2 Brofästet Gasverket Gasklocka 4 Västra Norra 1

Norra 2 Brofästet Gasverket Västra Gasklocka 4 Västra Norra 1

Status Completed Planned Planned Planned Completed Completed

Residual waste (kg/apt) in vacuum waste collection systems 212,6 kg/apt Not relevant Not relevant Not relevant 212,6 kg/apr 212,6 kg/apt

Paper (kg/apt) vacuum waste collection systems 32,8 kg/apt Not relevant Not relevant Not relevant 32,8 kg/apt 32,8 kg/apt

Plastic (kg/apt) sopsug 20 kg/apt Not relevant Not relevant Not relevant 20 kg/apt 20 kg/apt

Distance vacuum waste collection systems (m) 24 40 16 30 IU IU

Distance recycling rooms (m) 27 50 22 0 IU IU

Construction waste, BA (kg/GFA) 45,8 – – – 29,6 38,4

Etapp/xx	Norra 2	Brofästet	Gasverket	Gasklocka 4	Västra	Norra 1
	Norra 2	Brofästet	Gasverket Västra	Gasklocka 4	Västra	Norra 1
Status	Completed	Planned	Planned	Planned	Completed	Completed
Residual waste (kg/apt) in vacuum waste collection systems	212,6 kg/apt	Not relevant	Not relevant	Not relevant	212,6 kg/apr	212,6 kg/apt
Paper (kg/apt) vacuum waste collection systems	32,8 kg/apt	Not relevant	Not relevant	Not relevant	32,8 kg/apt	32,8 kg/apt
Plastic (kg/apt) sopsug	20 kg/apt	Not relevant	Not relevant	Not relevant	20 kg/apt	20 kg/apt
Distance vacuum waste collection systems (m)	24	40	16	30	IU	IU
Distance recycling rooms (m)	27	50	22	0	IU	IU
Construction waste, BA (kg/GFA)	45,8	–	–	–	29,6	38,4

Diagram 3.2 Compilation of construction waste, property developers in Norra 2, kg /m² GFA

Comments:

SSM and Viktor Hanson has disposed of plaster and filling compounds due to water damage.
Viktor Hanson has despite two extensive water damages managed to keep down the amount of construction waste, by in the early stage setting strategies and targets to minimize construction waste.
The Wallenstam preschool had problems with external waste in their waste containers.
Stockholmshem planned to minimize construction waste but had production problems that led to large amounts of concrete waste. In addition, Stockholmshem had problems with external waste in their waste containers.
Erik Wallin and the Wallenstam pre-school have not proactively dealt with the waste issue.
Skanska/HEBA had a substantial staff turnover on the projects and they think this is one of the reasons that waste was not prioritised.

Diagram 3.3 The distribution of construction waste and disposal in %, property developers in Norra 2