NOVEL APPROACHES TO QUARRY RESTORATION: REHABILITATION RESEARCH & PRACTICE

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1 Management of Abandoned Aggregate Properties Program NOVEL APPROACHES TO QUARRY RESTORATION: REHABILITATION RESEARCH & PRACTICE Kathryn Kuntz

2 Overview Introduction - MAAP Program - Pit and Quarry Rehabilitation

3 Overview Introduction - MAAP Program - Pit and Quarry Rehabilitation Research Projects - The Quarry to Alvar Initiative - Calcareous Fen Creation - Evaluating Non-conventional Alternatives

4 Overview Introduction - MAAP Program - Pit and Quarry Rehabilitation Research Projects Case Studies - The Quarry to Alvar Initiative - Calcareous Fen Creation - Evaluating Non-conventional Alternatives - Lawless Quarry - North Dundas Quarry - Seiling Quarry

5 Introduction Quarrying: One of the most ancient & important activities supporting human existence: building construction, tool manufacturing, road building (Larson et al. 2004) Ontario consumes 170 million tonnes of stone, sand and gravel each year (

6 Introduction Quarrying: Removes the present ecosystem Active Rehabilitation or Natural Succession are the only mechanisms by which another productive ecosystem can be established.

7 Introduction The Management of Abandoned Aggregate Properties Program The MAAP Program is dedicated to the rehabilitation and research of abandoned aggregate pits and quarries in areas of Ontario that are designated under the Aggregate Resources Act.

8 Introduction The Management of Abandoned Aggregate Properties Program The MAAP Program is dedicated to the rehabilitation and research of abandoned aggregate pits and quarries in areas of Ontario that are designated under the Aggregate Resources Act. MAAP is entirely funded by the aggregate industry through a portion of the annual 6-cent per tonne licence levy, as legislated in the Aggregate Resources Act (1990 R.S.O.). Reg.244/97 3(3)

9 Introduction The Management of Abandoned Aggregate Properties Program The MAAP Program is dedicated to the rehabilitation and research of abandoned aggregate pits and quarries in areas of Ontario that are designated under the Aggregate Resources Act. MAAP is entirely funded by the aggregate industry through a portion of the annual 6-cent per tonne licence levy, as legislated in the Aggregate Resources Act (1990 R.S.O.). Reg.244/97 3(3) $ projects 350 ha

10 Introduction The Management of Abandoned Aggregate Properties Program First Mandate: Site Rehabilitation Each year approx. 30 sites are selected for rehabilitation from different areas of the province based on factors like on-site hazards, site size, aesthetics, ease of accessibility and natural re-vegetation. Sites are rehabilitated at no cost to the landowner.

11 Introduction Until recently, MAAP has primarily undertaken the rehabilitation of sand and gravel pits - which is relatively straightforward since the substrate left behind is similar to the glacial tills that underlie much of southern Ontario.

12 Introduction A general lack of literature on hard-rock landscape restoration has limited MAAP in its quarry restoration attempts: Second Mandate: Research Projects Funding provided by the program for researchers performing work on aggregate property rehabilitation or other topics of relevance to the aggregate industry.

13 Research The main limitation to quarry restoration is absence of a clear restoration target (Larson et al. 2004) Surrounding land use? Prior land-use? TARGET COMMUNITY Current site conditions?

14 Research Selecting a target habitat based on existing site conditions: exposed limestone bedrock little topsoil periodic flooding Active Rehabilitation to a new target community which the site currently resembles could result in greater restoration success.

15 Research Quarry-to-Alvar Initiative Cliff Ecology Research Group

16 Research Quarry-to-Alvar Initiative Alvar Open areas of flat limestone Inconsistently covered with shallow, patchy soil Sparse vegetation, cryptogams, herbs, shrubs Cliff Ecology Research Group

17 Research Quarry-to-Alvar Initiative Alvar Open areas of flat limestone Inconsistently covered with shallow, patchy soil Sparse vegetation, cryptogams, herbs, shrubs Periodic drought and flooding High levels of spatial heterogeneity One of the most floristically-rich habitats in northern-temperate region Globally imperiled ecosystem Cliff Ecology Research Group

18 Research Quarry-to-Alvar Initiative Research Questions: 1) Similarities between abandoned limestone quarries and alvars in terms of ecological structure 2) Factors limiting ability of alvar species to colonize quarry floors Cliff Ecology Research Group

19 Research Quarry-to-Alvar Initiative Research Questions: 1) Similarities between abandoned limestone quarries and alvars in terms of ecological structure 2) Factors limiting ability of alvar species to colonize quarry floors Methods: Sampled 13 abandoned quarries for vegetation, physical factors, seeds, etc. Comparison between quarry floors and alvars Manipulative field experiment at four quarry sites plots seeded with a variety of soil ammendments. Cliff Ecology Research Group

20 Research Quarry-to-Alvar Initiative Results: Environmental characteristics strikingly similar; age explained greatest proportion of variation 77 of 246 species of vascular plants, bryophytes and lichens; 12% characteristic of alvars 50-60% natural conversion to alvar Cliff Ecology Research Group

21 Iris lacustris Research Potential Richness Realized (%) September 2004 May 2005 August Quarry Seeds Only (Q) Alvar Alvar Seeds Seeds Only + Sand (A) (AS) Alvar Seeds + Sand + Nitrogen (ASN) Seed-Addition Treatment Alvar Seeds - Quarry Residents (ARQ) Alvar Seeds + Quarry Seeds (AQ) Castilleja coccinea Cliff Ecology Research Group

22 Research Quarry-to-Alvar Initiative Recommendations for Quarry Operators (Summarized 19 into 4 main points) 1. Do not remove existing vegetation or soil - increases persistence in face of environmental uncertainty 2. Increase spatial heterogeneity and reduce disturbance - crevices, fractures and rock piles aid in trapping seed, retaining moisture, encourage diversity 3. Bring in alvar seeds - greater variety of species planted, greater likelihood of quarries serving as refuges for these species 4. Monitor and report on your restoration results - results change over time, little long-term monitoring exists Cliff Ecology Research Group

23 Research Calcareous Fen Creation Fen Rarest form of wetland in Ontario; groundwater-fed; Rich in calcium and magnesium; distinctive flora of rare calciphillic species Shown to establish naturally in abandoned shallow quarries

24 Research Calcareous Fen Creation Fletcher Creek Ecological Preserve Contains a naturally occurring calcareous fen, as well as an abandoned wet quarry. A 1 ha section of the quarry had water depths of 4-6 meters Also a large shallow section which is naturally rehabilitating to fen habitat.

25 Research Calcareous Fen Creation Goals: Determine the optimal ecohydrological protocols to rehabilitate quarries into calcareous fens. Discover to what degree a rehabilitated quarry will support the biodiversity found in a natural calcareous fen.

26 Research Calcareous Fen Creation Hydrogeological,, geochemical monitoring Transplant experiments ( (Carex aquatilus) Biodiversity Comparisons

27 Research Calcareous Fen Creation Carex aquatilus (water sedge) plugs transplanted from a natural fen into the quarry at a number of water depths were monitored for changes in stem number, height, and number of inflorescences. Transplant experiments ( (Carex aquatilus) Additional plugs of Scirpus acutus (hardstemmed bulrush), C. livida (livid sedge), and C. flava (yellow sedge) will be transplanted to the quarry to assess suitability of a range of vascular flora for quarry establishment.

29 Research Calcareous Fen Creation Hydrogeological,, geochemical monitoring Biogeochemical characterization of the natural site will enhance our understanding of nutrient and mineral cycling within calcareous fens. Chemical analyses will include major cations (Na, K, Ca, Mg, NH4+) and anions (NO3-, PO42-, SO42-), ph, conductivity, and carbonate content. Additionally, open water and pore water chemistry in the transplanted regions are monitored monthly to relate changes in transplants to solute gradients.

31 Research Calcareous Fen Creation Biodiversity Comparisons - Determine the optimum calcareous fen vegetation type for establishment in abandoned quarries.

32 Research Evaluating Non-conventional Alternatives Goals: Discover whether novel target communities are perceived as rehabilitation and are acceptable to the public. Landscape Architecture

33 Research Evaluating Non-conventional Alternatives Stakeholders responses to alternative endpoints are assessed through exposure to a variety of images Examples below are images used in agricultural landscape research Show views of the same location under different management plans Landscape Architecture

34 Research Qualitative: Ask respondents what they saw, what they liked, and disliked in each photo. Quantitative: Respondents rank the series of photos in response to a focused question about future likelihood. Results can be used to understand what translates to acceptable alternative future states, and what aspects of the alternatives are most or least appealing. Landscape Architecture

35 Case Studies Potential to apply Quarry to Alvar Research Lawless Little natural succession after abandonment on quarry floor Shallow / no soil

36 Case Studies Potential to apply Quarry to Alvar Research Lawless

37 Case Studies Lawless Potential to apply Quarry to Alvar Research 1. Existing vegetation and soil to remain 2. Increase spatial heterogeneity 3. Bring in alvar seed 4. Monitor and report our restoration results

38 Case Studies Township of North Dundas Located along major county road Attracts swimmers, cliff jumpers Potential for accidents

39 Case Studies Township of North Dundas Potential to apply Fletcher Creek Calcareous Fen Creation Research Several areas to be cut back to remove cliff jumping opportunities Lower cliff walls using large hoe ram & backhoe (fracture & excavate rock) Move the rock to re-shape quarry perimeter to suitable wetland depths (approx. 1 m)

40 Case Studies Township of North Dundas Potential to apply Fletcher Creek Calcareous Fen Creation Research

41 Case Studies Apply Calcareous Fen Creation Research and Alvar Research Seiling

42 Case Studies Seiling

43 Case Studies Seiling Water table very close to level of quarry floor Excavate 1/4 of floor to below water table and allow to flood Use extracted material to create rock piles, site heterogeneity

44 Case Studies Seiling Water table very close to level of quarry floor Excavate 1/4 of floor to below water table and allow to flood Use extracted material to create rock piles, site heterogeneity Seed with alvar species as per Lawless quarry restoration plan

45 Next Steps? Commercial availability of alvar species seed Commercial availability of calcareous fen transplant materials Few restoration protocols, based on limited study No benchmarks to measure success Stakeholder response to novel restoration strategies Public perception of alvar or fen communities

46 Next Year Short-term term results: Working through the application of these novel research strategies will provide valuable information about whether restoration targets based on existing site conditions prove cost-efficient, ecologically-sound and culturally acceptable.