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HomeMy WebLinkAbout4.20.23 discussion material April 13th, 2023 Yarmouth Conservation Commission Attn: Brittany DiRienzo, Conservation Administrator Town of Yarmouth 1146 Route 28 South Yarmouth, MA 02664 Re: Proposed Modifications to Salt Marsh Restoration Methodology Project Location: 184 Blue Rock Road, South Yarmouth, MA 02664 Dear Ms. DiRienzo and Yarmouth Conservation Commissioners, Crawford Land Management (CLM) respectfully submits the following information for preliminary review regarding the permissions we would like to gain in order to restore a portion of salt marsh at 184 Blue Rock Road. Bank stabilization and salt marsh restoration work was approved for this property in 2016 under SE 83-2065. The approved work has since been completed and the Order of Conditions has expired. The project did not satisfy the criteria needed to secure a Certificate of Compliance, and an Enforcement Order has been issued so that the project can be brought into compliance with the previously expired permit without needing to file a completely new Notice of Intent. While much of the salt marsh restoration area has persisted since the initial implementation several years ago, some areas have struggled to sustain. In particular, the salt marsh restoration area on the northern end of the property where it meets the wooden bulkhead from the adjacent property has had trouble sustaining long term. In this area, the elevation is approximately 18” lower than the elevation where the salt marsh has successfully sustained; this is possibly due to the adjacent bulkhead and the effects it has on altering water circulation, reflecting wave energy, and promoting downdrift erosion. At this time, we are proposing a new methodology aimed at increasing and holding the elevation in this difficult area and alleviating some of the effects likely caused by the adjacent bulkhead. We are proposing a salt marsh restoration strategy that we have implemented at other project sites in more recent years that also aims to raise the elevation (see Figure 1). With this strategy, we would install a fiber roll at the leading edge of the desired salt marsh to serve as a “soft” buffer. If the Commission is amenable, we would also like to try putting selective stone riprap in front of the fiber roll to help buffer wave energy and promote sediment accumulation (the stones would be small-medium size, and only as large as our field crews are able to carry so that we do not need special equipment or access). Behind the leading fiber roll, coir pillows would be placed on top of the sediment and covered with 2 layers of 900-gram coir matting and then staked and tied in place. Finally, under the coir matting, there would be a cobble berm comprised of a matrix of 6” rounded cobbles, coir and compost, and compatible sediment wrapped in a layer of 20 oz burlap and 2 layers of 900- gram coir. These measures would create a condition that raises the elevation, holds sediment in place, and provides a substrate for planting materials to become established in. The installation would be planted with native salt marsh grass plugs. We have tried a similar methodology at a project in Dennis, also along the Bass River, which was implemented this spring (see Figure 2). As we develop this project, we may incorporate elements of both details that we have provided. An alternative, slightly more robust approach to this would be placing larger boulders in front of the salt marsh restoration area as opposed to small-medium stone riprap. The boulders would need to be brought in by barge as opposed to being placed by hand. A similar project was completed by Shorefront Consulting which involved the placement of a row of stone boulders in front of a soft shoreline stabilization solution in order to add a layer of protection that’s not as robust as a revetment. Shorefront Consulting can speak to the potential for incorporating this type of solution. If the Commission is amenable, we would also like to try to hydroseed the existing fiber roll installation on the bank with an organic biotic soil media (ProGanics) and bonded fiber matrix (Flexterra). This is a relatively new technique that CLM is starting to use on some of our jobs, and we feel that it could help jump-start the establishment and growth of native grasses while the additional grass plugs are establishing. Product specification sheets are attached for your reference. We hope you see the value of the proposed modifications to the methodology for restoring this portion of salt marsh and vegetating the coir array. If you should have any questions, please don’t hesitate to contact me at jen@crawfordlm.com or (508) 477-1346. Respectfully, Jennifer Crawford, PLA, ASLA PRESIDENT, CRAWFORD LAND MANAGEMENT EXISTINGREVETMENTMITIGATION PLANTINGSSALT MARSHRESTORATION4'-0"EXISTING GRADE20"Ø FIBER ROLL; ANCHOR INPLACE W/ 1/4" CABLE & D88DUCKBILL ANCHORS EVERY30" OCMATIRIX OF 6" ROUNDED COBBLES(50%), COIR & COMPOST (25%) &COMPATIBLE SEDIMENT (25%)WRAPPED IN A LAYER OF 20 OZ BURLAP& 2 LAYERS OF 900 GRAM COIRDIMENSION VARIESTRANSITIONALHIGH MARSHRESTORATION-.6 MIN++ ELE 2 MINPLACE COIR PILLOWS ON TOP OF SEDIMENT& COVER W/ 2 LAYERS OF 900 GRAM COIRMATTING; STAKE & TIE IN PLACE; INSTALLSPECIFIED PLANTSDETAIL: SECTION A - A1Scale: 1/4" = 1'-0" 2" COIR BED PLACED ON TOP OF COMPATIBLE BANKSEDIMENT; ANCHOR W/ 1/4" CABLE D88 DUCKBILLANCHORS EVERY 30" O.C.; PLANT W/ AMERICANBEACHGRASS & SWITCHGRASS @ 12" O.C.MATRIX OF 3"-6" ROUNDED COBBLES (50%),COIR AND ORGANIC MATTER (25%) &COMPATIBLE SEDIMENT (25%)4' STAKES DRIVEN INTO UNDERLYING SEDIMENT;STAKE & TIE2" COIR BED PLACED ON TOP OFSEDIMENT; PLANT INTO COIR BED W/TRANSITIONAL HIGH MARSH SPECIESEXISTING GRADEEXISTING GRADE1000 GRAM COIR MATTING WRAPPED AROUNDFIBER ROLL, SEDIMENT & COIR BED AND TIEDINTO EXISTING SEDIMENT UNDERNEATH+1.0+ 2.0EXISTINGEXPOSEDFIBER ROLLS+ 0.3EXISTINGCOVEREDFIBER ROLLS20" DIAMETER FIBER ROLL;ANCHOR IN PLACE W/ 1/4"CABLE AND D88 DUCKBILLANCHORS EVERY 30" O.C.+2.74.8+SECTION A - A'1/4" = 1'-0" ProG-05 02/17 © 2017 PROFILE Products LLC. All rights reserved. 750 W. Lake Cook Road • Suite 440 • Buffalo Grove, IL 60089 • 800-508-8681 • www.profileproducts.com Profile and ProPlus are registered trademarks of PROFILE Products LLC. Solutions for your Environment, ProGanics and Biotic Soil Media are trademarks of PROFILE Products LLC. Patent 7,854,926 and 8,728,460 The World’s Most Advanced Engineered Soil Medium Loaded with a Patented Biological Soil Nutrient System ProGanics™ Biotic Soil Media™ (BSM™) is hydraulically applied for fast application and contains a patented, highly-concentrated biological soil nutrient system. This system makes nutrient uptake by plants more efficient, and initiates the nutrient cycling required to build and replenish healthy soil for sustainable vegetation. ProGanics also supplies critical organic materials, endomycorrhizae, seaweed extract, humic acid, biochar and other soil-building components for “life insurance” on even the most inhospitable sites. If the soil on your next project contains less than 5% organic matter, you need ProGanics to ensure your success. Hydraulically applying ProGanics is more cost-effective than typical topsoil or compost applications, and it overcomes soil deficiencies better than alternative Biotic Soil Amendments. Follow Profile’s 5 Fundamentals on your next project, starting with a FREE soil test. You’ll see exactly what you’re lacking, and how ProGanics BSM, used in conjunction with ProPlus® Prescriptive Solutions, can lay the foundation you need for success. REINFORCED VEGETATION HARD ARMOR NATURAL VEGETATION Rock/ Concrete GreenArmor™ System HP-FGM®/ET-FGM™ Flexible Growth Medium™ ProMatrix™ Engineered Fiber Matrix (Replaces ECB, BFM, SMM) Wood With Tackifier Straw/Hydraulic Mulch STEEPER SLOPES, HIGHER SHEAR STRESS & VELOCITIES Absolutely The Most Effective Erosion Control Medium Available. When your site demands the most from your erosion control solution, you need to demand Flexterra® High Performance-Flexible Growth Medium® (HP-FGM®) — the pinnacle of the erosion control industry. Fine grading and extensive soil preparation are unnecessary, allowing you to apply the product for immediate protection and superior performance at reduced overall costs. Flexterra HP-FGM Delivers: • The highest germination and vegetative establishment when compared to any rolled blanket or other hydraulically applied mulch available • Greater than 99% erosion control effectiveness immediately upon application • 100% biodegradability • Safe for even the most sensitive environments because it’s non-toxic High Performance Erosion Control HP Technology: Greener By Design 100% recycled, Thermally Refined® virgin wood fibers produce the highest yield and coverage per unit weight and are phyto-sanitized, eliminating weed seeds and pathogens 100% biodegradable, interlocking fibers increase mechanical bonding of the matrix to provide immediate performance upon installation 100% non-toxic biopolymers and water absorbents enhance erosion resistance and vegetative establishment Revolutionary patented Micro-Pore particles optimize water and nutrient retention Flexterra ® HP-FGM ® Technical Data: HP-01 02/19 * When uniformly applied at a rate of 3,500 lb/ac (3,920 kg/ha) under laboratory conditions. 1. ASTM test methods developed for Rolled Erosion Control Products that have been modified to accommodate Hydraulic Erosion Control Products. 2. Cover Factor is calculated as soil loss ratio of treated surface versus an untreated control surface. 3. Percent Effectiveness = One minus Cover Factor multiplied by 100%. 4. Functional Longevity is the estimated time period, based upon field observations, that a material can be anticipated to provide erosion control and agronomic benefits as influenced by composition, as well as site-specific conditions, including; but not limited to—temperature, moisture and light conditions, soils, biological activity, vegetative establishment and other environmental factors. 5. Large Scale testing conducted at Utah Water Research Laboratory. For specific testing information please contact a Profile technical service representative at 800-508-8681 (US and Canada) or +1-847-215-1144 (International). 6. Heated to a temperature greater than 193 degrees C (380 degrees F) for 5 minutes at a pressure greater than 345 kPa (50 psi) in order to be Thermally Refined®/Processed and to achieve phyto-sanitization. For technical information or distribution, please call 800-508-8681. For customer service, call 800-366-1180. For warranty information, visit profileproducts.com. 750 W. Lake Cook Road • Suite 440 Buffalo Grove, IL 60089 profileproducts.com © 2019 PROFILE Products LLC. All rights reserved. Profile, Thermally Refined, Flexterra, HP-FGM and High Performance-Flexible Growth Medium are registered trademarks of PROFILE Products LLC. ET-FGM, Flexible Growth Medium, GreenArmor, ProMatrix, Green Design Engineering, Earth-Friendly Solutions for Sustainable Results and Solutions for your Environment are trademarks of PROFILE Products LLC. SETTING THE BAR EVEN HIGHER Better Erosion Control—Flexterra® HP-FGM® immediately bonds to the soil surface. Its flexible yet stable matrix retains > 99% of soil, vastly reducing turbidity of runoff for up to 18 months. Greater Seed Germination and Growth—Flexterra HP-FGM delivers the highest growth establishment in the market, ≥ 800% via ASTM D7322, due to a combination of optimized water and nutrient retention. Safer for the Environment—Unlike rolled erosion control blankets, Flexterra HP-FGM has no nets or threads to endanger wildlife. It uses 100% biodegradable crimped interlocking fibers and 100% recycled and phyto-sanitized wood fibers. Flexterra HP-FGM is 100% safe in even the most sensitive environments. Earth-Friendly and Sustainable Results—Flexterra HP-FGM is a result of Profile’s Green Design Engineering™, creating cost-effective and environmentally superior solutions through the design, manufacture and application of sustainable erosion control and vegetation establishment technologies. Green Design Engineering™ is a holistic approach that combines agronomic and engineering expertise with advanced technologies to provide cost-effective and earth-friendly solutions. Profile strives to deliver Green Design Engineering across our team of consulting professionals, innovative products and educational resources. GREEN DESIGN ENGINEERING ™ EARTH-FRIENDLY SOLUTIONS FOR SUSTAINABLE RESULTS™ PS3 is a free, comprehensive 24/7 online resource you can use to design a project and select the right products that address both the physical and agronomic needs of your site. It will help you develop holistic, sustainable solutions for cost-effective erosion control, vegetation establishment and subsequent reductions in sediment and other pollutants from leaving disturbed sites. Because good plans start with the soil, PS3 offers free soil testing to ensure this critical step is considered. 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TEST METHOD UNITS TESTED VALUE PHYSICAL PROPERTIES* Mass/Unit Area ASTM D65661 g/m2 (oz/yd2)≥ 390 (11.6) Thickness ASTM D65251 mm (in)≥ 5.6 (0.22) Ground Cover ASTM D65671 %≥ 99 Water-Holding Capacity ASTM D7367 %≥ 1,700 Material Color Observed n/a Green ENVIRONMENTAL PROPERTIES* Biodegradability ASTM D5338 n/a Yes Ecotoxicity EPA 2021.0 %48-hr LC50 > 100% Effluent Turbidity Large Scale5 NTU < 250 PERFORMANCE PROPERTIES* Cover Factor2 Large Scale5 n/a ≤ 0.01 Percent Effectiveness3 Large Scale5 %≥ 99 Functional Longevity 4 ASTM D5338 months ≤ 18 Cure Time Observed hours 0-2 Vegetation Establishment ASTM D73221 %≥ 800 PRODUCT COMPOSITION TYPICAL VALUE Thermally Processed 6 (within a pressurized vessel) 100% Recycled Virgin Wood Fibers 80% Wetting agents (including high-viscosity colloidal polysaccharides, cross-linked biopolymers, and water absorbents)10% Crimped Biodegradable Interlocking Fibers 5% Micro-Pore Granules 5%