PROJECT DESCRIPTION

This plan was written for a parcel of Clayton Development's land located in Dartmouth known as Portland Hills. This parcel is the remainder of Parcel CD-1. The property consists of a Portion of Block N-2; Portion of Parcel RM-1; Portion of Parcel RM-2; Remainder of Parcel RM-3; and the Remainder of Parcel RM-4R as shown on Figure No. 1.

The development of the site will include approximately 116 acres of single family, 17 acres of lifestyle, 32 acres of semi's / townhouses, 26 aces of multiple, 9.2 acres of commercial, 54 acres of parkland with the remainder of the land used for roadways.

Erosion and sediment control measures discussed in this plan will be implemented in accordance with the Nova Scotia Department of the Environment Erosion and Sedimentation Control Handbook for Construction Sites.

Site Topography

The site is located in Dartmouth and is bounded by Portland Street to the north, Inishowen subdivision to the east, Portland Estates subdivision and Morris lake to the west and the Kuhn property to the south. The site area is 263.6 acres.

The site is located in the Morris Lake Watershed. The area of the Morris Lake watershed is approximately 4223 acres. It is fed by surrounding area and smaller lakes upstream that flow into Morris Lake. Morris Lake flows into Cow Bay River, which then flows to Cow Bay. The 263- acre development represents 6.23% of the Morris Lake watershed. An outline of the site in relation to the watersheds can be seen in Figure No. 2.

Surface water from the site drains via streams crossing from the north east to the south west where they ultimately empty into a shrub bog wetland along the shore of the lake before entering Morris lake. Subsurface flow occurs in some portions of the stream/ditch due to rock-fill and fractured bedrock. The watercourses also collects runoff from the properties to the north and east.

Site Soils

The Griffiths Muecke Report of May 1998 reveals that the underlying bedrock in the area consists of Goldenville greywacke overlain by Wolville soil, which is a sandy clay loam. The bedrock is evident at the surface at the northern end of the lake where the first construction will begin.

ENVIRONMENTAL CONCERNS

PHASE 1 ENVIRONMENTAL SITE ASSESSMENT

A phase 1 environmental site assessment performed by Jacques Whitford Environmental Limited in 1997 revealed no evidence of environmental contamination.

WETLANDS

There appear to be no significant wetlands beyond the 100' buffer along the shoreline of Morris Lake.

WATERCOURSES/WATERBODIES

The property contains two main streams. A site evaluation was performed by Jacques Whitford Environmental Limited to determine the quality of existing fish habitat and the effect of future development in the area. The results of the evaluation revealed that the streams at the site are considered fish habitat (see attached letter). The watercourses appear to predominantly carry local surface runoff from precipitation events and snow melt. The streams meander across the site and the only proposed alteration to the streams involve piping the streams and filling over with rock from the site (Greywacke) for the purpose of roadway crossings. Any changes to, or work on these streams will require a stream alteration permit from the Nova Scotia Department of Environment (NSDOE).

Morris Lake supports a range of fish species, which are native to the region.

TROPHIC STATUS OF LAKES

The trophic status of a lake refers to the level of plant productivity. With development of the surrounding property the trophic status of the lakes will deteriorate. Higher phosphorus loading would result in an increase in algal growth and depletion of dissolved oxygen. However, as determined by the Griffiths, Muecke Report Morris Lake is generally mesotrophic although eutrophic conditions are evident at the northern end of the lake.

SOIL EROSION

The geology of the site consists of areas of exposed bedrock with most of the site overlain by a glacial drumlin consisting of Lawrencetown till as confirmed by testpit investigations by JWA in March of 2000. The area is considered to have high risk of soil erosion. Imported soil will be limited to top soil needed for landscaping. Standard erosion and Sedimentation control measure will be employed for all erodable soils, see Section 7.0: Erosion and Sedimentation Control Plan.

THE STORMWATER MANAGEMENT PLAN

The objectives of the storm water management plan are as follows:

•	Ensure that the quality of the runoff is as close to predevelopment conditions as possible, while ensuring the runoff coefficient does not exceed the industry standard for single family development.

•	Prevention of deterioration of adjacent water bodies. Minimize erosion and mobilization of sediments.

•	Maximize removal of mobilized sediments on the site.

•	Water quality on and leaving the site remain suitable for public health and aesthetic uses.

•	Reduce the normal post development amount of phosphorous entering the lake through storm water generated on the site by 40%.

STORMWATER QUANTITY/RATE OF FLOW

ML –10 (a) encourages development to reproduce the predevelopment hydrological conditions while (d) and (e) encourage the minimization of disturbance to the topography while preserving and utilizing the natural drainage systems. As it is impossible to achieve (a) without ignoring (d) and (e) it was decided that the important issue in (a) was the quality of the water not the quantity. Therefore, the quality of the water will be the driving force for the design of the storm water system. The Quantity / Rate of flow will be controlled by an overall c-factor of 0.55 which is the industry standard for single family development.

Roof leaders wherever possible will be dropped on the surface to recharge the ground water and minimize the piped flow to the lake.

STORMWATER QUALITY

To prevent deterioration of the water bodies in the area the stormwater runoff will be treated on the site. During construction an erosion and sediment minimization plan will be followed to minimize sediment mobilization. Mobilized sediments will be contained by the use of silt fences and stormwater ponding on site.

Stormceptor systems (or approved equals) will be installed to remove sediments, petroleum products and phosphorous . These systems will be designed in accordance with specifications to treat water to a level suitable for discharge into a Type 2 habitat (i.e. water contains feeding areas, particularly for adult fish, and unspecialized spawning areas, such as that used by minnows).

The design of this system is based on the criteria that the initial ½" of rainfall during a storm event flushes the site. Therefore, with this initial flow being captured and processed, the remaining runoff can be conveyed directly to the receiving body of water with no concern of contamination.

THE STORMCEPTOR SYSTEM (or approved equal)

A Stormceptor system is a vertically oriented storm water separator that removes oil, sediment and other contaminants in urban runoff. The lower treatment chamber of the Stormceptor system allows liquids with a specific gravity less than water to rise to the surface and suspended solids to settle to the bottom of the chamber. Stormceptors contain an emergency bypass system that allows runoff to directly circumvent the lower chamber and prevent there suspension and scour of settled pollutants. Stormceptor is capable of treating first flush (i.e. the initial runoff during a rain event containing the contaminants that have accumulated on the site.)

PROPOSED ALTERATIONS OF THE AREA

Figure 3 shows the proposed alteration to the project site. The total area of the site is approximately 263 acres. The project includes clearing, grubbing and grading of the site and development of the commercial, multiple and residential properties.

The following sections will describe the control plan and maintenance procedures to prevent the occurrence of on-site and off-site erosion and sedimentation.

EROSION AND SEDIMENT MINIMIZATION PLAN

The following is a summary of the plan, see appendix "X" for the detailed plan and Best Management Practices.

Given the highly erodable soils on the site the requirements for erosion and sedimentation control are critical. Therefore, strict compliance with the following procedures are required.

PROTECTION MEASURES DURING SITE DEVELOPMENT

The erosion and sedimentation control plan during construction includes:

•	Silt fences, etc. installed before grubbing operation.

•	Clean run-on water controlled/diverted by installation of channels, berms, and grading.

•	Exposed soil minimized via rapid cover by mulch, gravel etc.

•	Soil exposure controlled relative to forecasted weather conditions.

•	Site grading to low slopes complete with ponding depression areas and shallow ditches to retain stormwater.

•	Monitoring plan set up.

PERMANENT PROTECTION MEASURES

The erosion and sedimentation control plan for permanent stabilization is:

•	All disturbed surfaces will be stabilized.

•	Parking lot runoff routed through Stormceptor units (or approved equal) for removal of sediments, oils and greases.

•	Commercial roof and parking lot ponding to retain peak flows in rain events.

•	Periodic inspection of erosion and sedimentation control measures to ensure continued effectiveness.

MAINTENANCE PROGRAM

The maintenance program to ensure the effectiveness of the erosion and sedimentation control plan is as follows:

•	Inspection of temporary measures will be performed daily (and during precipitation events) to check for damage. Damaged structures win be repaired.

•	Environmental protection structures will be maintained (including removal of silt material) until stabilization of disturbed areas has occurred. The structures will then be removed and the area will be regraded and stabilized.

•	Inspection and maintenance of Stormceptor systems (or approved equal) will be performed at a minimum quarterly frequency and per manufacturers recommendations and as site conditions warrant. This monitoring frequency complete with result reports submitted to the HRM will continue for a two year period, at the end of which it will be reassessed.

Appendix "X"

EROSION AND SEDIMENT MINIMIZATION PLAN

CONSTRUCTION SCHEDULE

Environmental Concern

The probability for erosion and sedimentation on construction sites is highest during precipitation events. According to 30 years records at Shearwater Airport, the greatest amounts of precipitation occur during winter and spring months. The construction schedule for the Portland Hills - Phase I development is from March to May 2000, inclusive.

Soils within the property are classified as Wolfville Soils, which are characterized as sandy clay, loam with high potential for erosion (Griffiths Muecke 1998). Construction on the site must proceed with caution to ensure that the environmental protection measures are adhered to and enforced.

CLEARING AND GRUBBING

Environmental Concern

Clearing activities in the vicinity of a watercourse will cause disturbance of the protective vegetative buffer or riparian zone adjacent to the watercourse and could subsequently lead to erosion of the approach slopes and sedimentation into and the obstruction of the watercourse. For construction projects, there are three categories of erosion and sediment control: runoff controls, erosion protection, and sediment interception.

Runoff controls limit or contain soil movement from the construction site, minimizing raindrop impact on the soil and reducing runoff volume and runoff velocities. Generic controls considered for this Project are discussed below.

Erosion protection measures are used to reduce or eliminate the detachment of soil particles by falling raindrops or to resist sheet or channel flow. These measures are placed on, or applied to, the soil surface and are often used in conjunction with runoff control and sediment interception measures. Erosion protection measures to be used as appropriate in pipeline construction include:

gravel sheeting;

mulches;

tackifiers;

erosion control blankets; and

revegetation.

Revegetation is generally used only for permanent protection and often requires another form of temporary protection measure to be successfully established.

The key to managing runoff and stormwater flows is to minimize erosion and sedimentation. Methods for managing stormwater flows include:

wet and dry pond for stormwater detention;

infiltration systems;

engineered stormwater systems;

onsite detention facilities; and

constructed wetlands.

Best Management Practice

Before any clearing or grubbing commences. clearing limits, easements, setbacks, sensitive/critical areas and their buffers, trees and drainage courses will be delineated with flagging tape and enviro-fences. This practice ensures workers can clearly recognize areas to be protected.

No clearing or construction will occur within the protective green/belts/protected sensitive areas as identified on the development plans.

To reduce the velocity of runoff, crop residues, plants, and rough soil surfaces are applied to help spread the flow of water over a greater area and into a thin layer.

Diversion berms are commonly used on slopes to intercept sheet flow on exposed surfaces and to reroute flow into undisturbed areas. Erosion protection is required at the berm outlets. Check dams are a temporary measure constructed in ditches, swales, or chutes to reduce hydraulic gradient and flow velocity, thus minimizing the potential for erosion of the channel.

•	Sediment traps and swales or dikes (diversion channels) will be installed around each lot before construction begins to control excavation water and where required to intercept runoff \from	sheet flow from entering the disturbed house pad area. Necessary erosion control measures such as interception ditches will be completed prior to clearing of each work site.

The work site will not be cleared nor will topsoil be removed prior to commencement of

construction

Cleared and graded areas will be limited to minimize the area of exposed soil

Minimal amount of natural vegetation and topsoil will be removed at each construction site

Home sites will not be cleared or grubbed until actual construction is ready to commence, with the exception of where bulk excavation is necessary, those areas will be stabilized immediately following the completed excavation.

Bulk excavation sites will be prepared by the contractor to foundation ready and fully stabilized. For the remaining lots, the extent of clearing and lot development will be designed by the developers consultant and supervised once the house plans are finalized for each lot. This practice avoids unnecessary clearing and grubbing as all house plans and their pads will not conform to the same design.

Mulches consisting of wood chips, stone or commercial anti-erosion mats will be used to limit erosion on land, which is cleared of vegetation.

All non-mercantile timber will be chipped on site and used as temporary protective cover over exposed and disturbed areas.

Grubbed material, which is not used for fill, will be disposed offsite in accordance with Nova Scotia Department of Environment legislation and Halifax Regional Municipal Bylaws.

The contractor and developer will maintain a stockpile of erosion control material onsite.

GRADING

Environmental Concern

Grading requirements near watercourses can be extensive in housing developments to accommodate lot and street development. Accordingly, slopes may be contoured to allow for the site development. Disturbance of the slopes may cause instability, which could result in erosion and subsequent sedimentation of watercourse and Morris Lake.

Soil loss from slopes may occur even with erosion and runoff control measures. If this soil can enter a waterbody, mitigative measures will be required to intercept it. Methods used to trap sediment include vegetated buffer strips, silt fences, filter berms, and sediment traps.

Best Management Practices

Construction along the access roads will be sequenced such that each section is to be completed and stabilized before proceeding to the next section unless overlapping work is approved by the project engineer.

Work along the streets will not exceed 200 metres. The contractor will work continuously until the streets are completed. If work is halted for 5 days, temporary stabilization structures and material will be installed.

A crushed rock construction entrance will be established to prevent tracking of mud offsite and through the new and adjacent subdivisions.

Lot grading will entail completion of each lot driveway first and vehicular travel on the lot will be restricted to the driveway. Access to each lot will be restricted to one driveway.

The driveway will consist of clear stone or gravel to a thickness of three to six inches. If necessary, filter fabric will be laid under the stone if fines are encountered. This surface will be maintained during construction.

Once the house pad is graded, the exposed pad will be graveled with clear stone. All exposed soil or unworked home sites will be stabilized no more than 5 days upon completion of the construction.

•	No mud, debris or other excavation material will be placed on the street. Fill material will not be stored next to the curb. Fill will be piled within the perimeter of the cleared lot (no more than 3 metres around the house pad) until needed for cut lots or landscaping.

•	Imported fill material will be assessed to ensure that material is not composed of high percentage of fines.

All stockpiled fill material will be covered with tarps or other material, which are secure, to protect it from rainfall.

Diversions will be constructed at the top of each fill slope at the end of each work day, as needed. Diversions will be located at least 0.6 m uphill from the tope edge of each fill. The outlet of diversions, if free of sediment, will be located on undisturbed or stabilized areas when possible. Otherwise, sediment laden runoff must be diverted to a sediment retention structure.

Sediment traps, smaller than sediment basins, are more easily installed and moved as grading progresses, will be incorporated into the drainage pattern around each house lot. Sediment traps will serve areas less than 2 ha (5 acres). These structures will be placed downslope of the home lots to intercept runoff on relatively level areas or natural depressions.

Sediment barriers will be used to treat small areas and include enviro-fencing, straw bales, filter fabric, gravel and earth berms. Barriers will be placed below disturbed areas subject to erosion including along the contour of exposed slopes; at the base of a slope; along a street or sidewalk; and at storm drain inlets. Barriers will not be placed in a drainage way with high volume or high velocity.

•	All water pumped from ditches, swales or sumps should be discharged away from the watercourse and filtered through a sediment trap, 2 m3 (3 yd3) of class B gravel, filter bag, or undisturbed vegetation to filter out solid material before the water enters the watercourse.

•	Silt accumulation along silt fences and swales will be removed regularly.

•	Long and steep slopes on the construction site will be minimized to prevent erosional velocities from developing. If long slopes are present, they will be benched to interrupt the flow of water and minimize erosion.

CULVERT INSTALLATION

A buffer zone will be established along the watercourse by pacing geotextile silt fences on both sides of the channel. Work must be completed in the dry, therefore water will be diverted around the construction site.

Diversion channels can consist of a ditch lined with polyethylene liners that are properly placed and secured. Sandbags or an impermeable dam will be installed at the inlet to divert the flow. Inlet and outlet protection to prevent erosion and scouring at the ends will be installed.

Unlimited fording of watercourses by construction equipment will not be permitted.

•	Culverts will be properly designed to handle the increased flows as a result of development and comply with NSDOE regulations with respect to the Watercourse Alteration Permit.

Side banks of the channel will be stabilized and revegetated subsequent to completion of the culvert installation

INSPECTION AND ENFORCEMENT

Environmental Concern

Thorough maintenance of all temporary and permanent erosion and sediment control measures will ensure the integrity of the aquatic resources they protect. Monitoring of the site following major rainstorms will determine that runoff control devices are effective and allow for the removal of accumulated sediment.

Best Management Practices

With respect to sediment control, all work is to be completed to the satisfaction of the project engineer and HRM.

•	On-site inspection will be an active part of any near-lake development and management

program. The effectiveness of control measures will be inspected and monitored during rain events and maintained and upgraded as necessary or as directed by the Project Engineer or Environmental Inspectors.

•	The Contractor and Project Engineer will incorporate a routine end-of-day check to ensure the integrity of the protection measures.

Monitoring of meteorological conditions and forecasts as a proactive means will be conducted to minimize the potential for erosion.

RESTORATION AND PERMANENT PROTECTION MEASURES

The final restoration phase is critical for mitigation long-term impacts to watercourses. Clayton Developments will incorporate all appropriate mitigative to ensure proper restoration of the sites adjacent to watercourses and channel of each watercourse.

Environmental Concern

Proper restoration of the watercourses and adjacent areas will minimize post-construction impacts to these areas. Implementation of permanent protection measures such as a stormwater management plan will minimize the volume of stormwater constituents into Morris Lake.

Best Management Practices

The sites will be reclaimed immediately to limit sustained erosion.

Vegetative growth or rock facing (riprap) on steep slopes will be restored in al denuded areas by seeding or laying sod.

Prompt re-establishment of vegetation will reduce the need for costly remedial measures caused by erosion damage to slopes.

•	The targets to minimize and reduce contaminant input to Morris Lake will be met through implementation of four control devices that have proven to reduce contaminant inputs. The strategy recommended for this site is to provide an integrated approach to stormwater management that is premised on controlling surface runoff and pollution at the source. Therefore, a hierarchy, or train, of stormwater management practices may include:

- Stormwater lot level controls, which will be achieved using an overflow catchbasin

piping arrangement, storage upon the roof and parking lot, Stormceptor oil/water

separation units; and end-of-pipe stormwater management facilities which will consist of

Stormceptor (or approved equal), and velocity breaks prior to storm water entering the

natural water courses.

- Stormwater lot level controls involve measures to store and treat stormwater before it

reaches the street conveyance system.

- End-of-pipe stormwater management facilities found to be most suitable for the proposed development for treatment of the stormwater and removal of phosphorous is the Stormceptor (or approved equal) system for the following reasons:

- performance does not depend upon soil characteristics;

- no additional disturbance to the natural areas to create retention ponds or artificial

wetlands;

- the performance is definable and measurable; and

- maintenance is simple and the HRM has the equipment required.

HAZARDOUS MATERIAL STORAGE AND HANDLING OF FUELS AND HAZARDOUS MATERIALS

Environmental Concern

Accidental spills of fuels, lubricants or other chemicals may enter watercourse and eventually Morris Lake. Proper storage and handling of these materials should prevent the probability of accidents.

Best Management Practice

•	Machinery maintenance will not be performed in or near a watercourse, ditch or storm sewer. Some examples of maintenance include washing out cement mixers, changing oil, greasing, spray painting, cleaning of spraying equipment or painting equipment, etc.

Any hazardous liquid including fuel and lubricants will be stored in a designated area surrounded by an impervious berm which would contain a spill of the volume of all stored liquid.

Solid hazardous materials including cement, lime and sulphur should not be stored within 25 m of a watercourse.

Any spillage of a hazardous material into any watercourse will be reported to the Nova Scotia Department of Environment's Environmental Emergencies 24 Hour Service (424- 5620).

CONTINGENCY PLANNING

Extreme Storm Events

Extreme storm events (usually subtropical storms) can result in extensive erosion due to heavy rainfall impact and the associated stormwater runoff. Erosion of approach slopes adjacent to watercourses is to be expected during these events. Watercourse flows can be expected to increase suddenly, possibly exceeding the capacity of ditches, swales and sediment traps. Throughout the course of construction, the Environmental Inspectors must be aware of current meteorological predictions and the potential ramifications. Subject to a review of the construction activities planned for the day and the locations of these activities, the prediction of storm events will result in the suspension in the vicinity of watercourses and wetlands.

Excessive runoff can be mitigated or controlled by the use of additional diversion berms, straw bale check dams, sediment fences and/or sandbag barriers. Additional sediment interception measures such as sediment traps can also be constructed quickly. The CONTRACTOR will ensure that equipment, personnel and required materials will be available for application as required.

Following extreme storm events, Environmental Inspectors, will conduct environmental monitoring in those area deemed at risk. Recommendations regarding erosion control will be made by the Environmental Inspectors as required.