4UNCOVERED

How might artificial landscapes act as a way to acknowledge the contamination history on a site while pursuing its remediation?

Project Type: Landscape, Community

Completed: Spring 2020, 2nd Year Design Studio

Location: Arlington, VA

Programs: Rhino 6, AutoCAD, Lumion, Adobe Suite

Supervised by: Rick Andrighetti | reandrighetti@uwaterloo.ca

UWSA Energy + Design Award Nomination + Honourable Mention

On the site of an urban waterfront and former industrial brown-field, a recreational re-use park is established across the Potomac River from Washington DC. An addition project within the park aims to reveal the complex history of the landscape while simultaneously healing the soil below using its integrated bio-venting technology. Analysis of the site’s industrial use and contamination history reveals lingering lead and PCB remnants in the soil, and though although most of the soil in the park has been remediated through layering and treatment, an asphalt cap has been used to contain the toxic contaminants within one particular area.

A system of wind turbines and bio-venting is developed and creates a “line of action” on the boundary of the asphalt cap, connecting human programs to the remediation of the soil. This formulates the structure of the community library, and frames the expanse of the resulting playground situated above the remediation process.

Due to the recent urban developments around the area, the adjacent neighbourhoods are becoming increasingly inhabited by a more diverse demographic of people, including many young professionals and families, in addition to the more senior current residents. There is currently a lack of gathering and social spaces beyond mini parkettes and underground malls. The project aims to curate specific spaces that can be enjoyed by all, whether it be a birdwatch tower, playgrounds, or a place to study.

The man-made surface of the sculpted terrain is a reminder that a natural looking landscape may not be truly sustainable, whereas a constructed landscape specific to the needs and requirements of natural processes will maintain a healthier and more sustainable landscape over time.

Design Strategies

Educate and acknowledge the history of the site

Remediation of the soil on-site using non-intrusive methods

Create open public gathering spaces for the community

Establish different programs for the wide age group moving to the area

Improve access to the water and nature across the tracks

What strategies can we use to create a usable landscape while remediating the site?

The wind turbine and bioventing apparatus creates a line of action on the boundary of the asphalt cap, connecting the programs above ground to the remediation of the soil below. Vertical axis wind turbines were chosen as a clean energy source of a small scale that is less intrusive to birds and human activity. Kinetic energy is collected from the wind turbine and is converted into electric energy that powers the blower, integrated into the structure of the building, which sends 02 into the soil for bioventing, encouraging native bacteria to break down hydrocarbons from PCBs and petroleum-based contaminants.

These apparatus line the edge of the asphalt cap, and also act as the structure of the new building - a community library and research center that monitors the remediation process.

How can we address the way contamination and the asphalt cap affects botanical design on site?

The soil mounds in the sculpted play-scape allow native trees to be brought back into the landscape without risk of their roots seeping into the contaminated soil. The height of each mound is determined by the amount of root space that is needed for each specific native species. The sides of the mounds are lined with corten metal, and acts as wayfinding and educational signage about the site and the plants.

The permeable material at the apex of the mounds allow for easy water delivery to the plants, and the sculpted design assists the drainage of water through the plaza and eventually into the nearby rain garden.

Phytoremediation is used in areas of the site outside the asphalt cap. The chosen plants are both hypperaccumulators and high biomass plants, which will take in and accumulate the heavy metals left in the soil.

Initial Concept Sketches

A community library is developed in the space created by the peeling back of the artificial landscape. The structure of the building, along with the strips of landscape, follow the grid created by the turbine system. An open reading space continues the wave system of the play plaza in the interior flooring, blurring the lines as you enter the building. A line of machinery managing the turbine and bio-venting system separates two major areas of the building - public community space and quiet reading.