Exhibit 4 APPENDIX E Benthic Assessment Report Vermont Green Line Devco, LLC Exhibit 4: Environmental Effects Vermont Green Line Project Article VII Application Benthic Macroinvertebrate Sample Analysis Report Vermont Green Line Project Lake Champlain Vermont and New York PREPARED FOR: TRC Companies, Inc. 124 Grove Street Franklin, Massachusetts 02038 PREPARED BY: ESS Group, Inc. 10 Hemingway Drive, 2nd Floor East Providence, Rhode Island 02915 Project No. T332-000 Revised January 19, 2016 www.essgroup.com BENTHIC MACROINVERTEBRATE SAMPLE ANALYSIS REPORT Vermont Green Line Project Vermont and New York Prepared For: TRC Companies, Inc. 124 Grove Street Franklin, Massachusetts 02038 Prepared By: ESS Group, Inc. 10 Hemingway Drive, 2nd Floor East Providence, Rhode Island 02915 Project No. T332-000 Revised January 19, 2016 © 2016 ESS Group, Inc. – This document or any part may not be reproduced or transmitted in any form or by any means, electronic, or mechanical, including photocopying, microfilming, and recording without the express written consent of ESS Group, Inc. All rights reserved. TABLE OF CONTENTS SECTION PAGE 1.0 INTRODUCTION ..................................................................................................................................... 1 2.0 METHODS .............................................................................................................................................. 1 2.1 Laboratory Analysis .......................................................................................................................... 1 2.2 Data Analysis .................................................................................................................................... 2 3.0 RESULTS ................................................................................................................................................ 2 3.1 Taxa Richness .................................................................................................................................. 2 3.2 Macrofaunal Density ......................................................................................................................... 3 3.3 Macrofaunal Community Composition ............................................................................................. 3 3.4 Quality Assurance/Quality Control.................................................................................................... 7 3.5 Summary of Results ......................................................................................................................... 7 4.0 REFERENCES ........................................................................................................................................ 7 TABLES Table A Summary of Key Statistics from the Benthic Sample Analysis Table B Relative Abundance of Taxa Encountered Table C Most Widespread Taxa Encountered FIGURES Figure 1 Taxa Richness by Sample Figure 2 Total Macrofaunal Density by Sample Figure 3 Zebra Mussel Density by Sample Figure 4 Relative Abundance of Stylodrilus heringianus by Sample APPENDICES Appendix A Chains of Custody Appendix B List of Selected Taxonomic References Appendix C Benthic Sample Taxonomy and Enumeration Results © 2016 ESS Group, Inc. 1.0 INTRODUCTION On behalf of TRC Companies, Inc. (the Client), ESS Group, Inc. (ESS) analyzed 30 samples collected from benthic habitats within the Lake Champlain portion of the Vermont Green Line Project cable route. Benthic macroinvertebrates were the primary target of the analysis and are defined as organisms greater than 500 microns (μm) in length that either live on or in aquatic sediments, including mollusks, primitive (unsegmented) worms, annelids (segmented worms), crustaceans and insects. 2.0 METHODS 2.1 Laboratory Analysis ESS received a total of 30 samples from the Client, including 20 samples on November 20, 2015 and 10 samples on December 2, 2015 (Appendix A). All samples originated from Vermont and New York waters of Lake Champlain. Samples were collected with a 0.1 m2 modified Day grab sampler, then field-sieved and fixed on board the survey vessel. The sieve mesh size was 0.5-mm and 10% neutral buffered formalin was used as the field fixative solution. Upon receipt at the laboratory, benthic samples were logged and checked for adequate preservation. Prior to sorting, sample material from each sample was emptied in its entirety into a 0.5-mm mesh sieve. Tap water was gently run over the sieve to rinse away any additional fine sediment that was not removed during the field sieving process as well as to remove the formalin solution prior to the microscope work. Rinsed samples were preserved in 70% ethanol. Each benthic sample was sorted to remove benthic organisms from residual debris. Samples with a high volume of sample debris were sub-sampled. Sub-sampling was conducted using a randomized procedure, in which the material was first split into 32 equal fractions using a gridded tray. Each grid in the tray was assigned a unique number. Sample fractions (sub-samples) were then selected using a random number sheet and carefully removed from the tray and sorted in their entirety under a high-power dissecting microscope (up to 90X magnification) until a target of at least 100 organisms was retained. The unsorted and sorted fractions of each sample were retained separately and preserved in 70% ethanol. Samples with minimal material or with fewer than 100 organisms were sorted in their entirety (i.e., without sub-sampling). For quality assurance and control (QA/QC) purposes, a second qualified staff member (quality assurance officer) resorted 10% of the samples analyzed by each sorter to ensure organisms were being adequately retained. The quality assurance officer checked the sorted sample material for any remaining organisms and calculated an efficiency rating ( E ) using the following formula: n E = 100× a na + nb Where na is the number of individuals originally sorted and verified as identifiable organisms by the QC checker and nb is the number of organisms recovered by the QC checker. If the original sorter achieved E < 90% (i.e., less than 90% of the organisms in the sample removed), an additional sample sorted by that analyst was re-examined by the quality assurance officer. All sorted organisms were subsequently identified by a qualified taxonomist to the lowest practicable taxonomic level using a dissecting microscope with magnification up to 90X and readily available taxonomic keys. Oligochaetes and non-biting midges (Chironomidae) were mounted in CMC-10 mounting media using methods consistent with those outlined in Epler (2001). Identification of slide-mounted organisms was conducted under a compound microscope with magnification to 1,000X. The primary taxonomic references used for macroinvertebrate identification are listed in Appendix B. © 2016 ESS Group, Inc. Benthic Macroinvertebrate Sample Analysis Report – Vermont Green Line Project Revised January 19, 2016 Enumerations of macroinvertebrates identified from each sample were recorded directly in an electronic spreadsheet. Prior to data summary, species abundances for each sample were standardize to number of individuals per square meter, taking into account the sampling equipment dimensions and sub-sampling effort. 2.2 Data Analysis Measures of benthic macrofaunal diversity, abundance, and community composition were selected to describe existing conditions. The rationale behind selection of each measure follows. Diversity (Taxa Richness) Taxa richness is the number of different taxa that are found within a given area or community and is widely accepted as a robust assessment measure of diversity (Magurran 2003). For this study, taxa richness is defined as the total number of unique taxa found in a sample. Abundance (Macrofaunal Density) Macrofaunal density is an estimate of the number of individuals per unit area. The density of benthic organisms responds to disturbance as mitigated by the tolerance (or preference) of a given organism to the particular source of disturbance. Density may vary substantially over small areas or short periods of time and should therefore be interpreted cautiously. For this study, macrofaunal density is expressed as the number of organisms per square meter. Community Composition Community composition is a multivariate measure identifying the different benthic taxa present and respective abundances of each taxon. This descriptive measure uses information regarding the taxa present, providing detail to complement and help interpret summary metrics of diversity and abundance. 3.0 RESULTS Results of the benthic sample analysis, including taxa richness, density, and community composition are presented in the following sections. 3.1 Taxa Richness The total number of taxa identified from the samples examined was 36 (Table A). Taxa richness per sample ranged from 1 at multiple locations (B-10, B-12, B-14, B-18, B28, B-30, B-32, B-34, and B-39) to 19 taxa at B-1 (Figure 1 and Appendix C) with a mean taxa richness of 4 taxa per site (Table A). Table A. Summary of Key Statistics from the Benthic Sample Analysis Statistic Value Number of Samples 30 Mean Density per Square Meter (±1 SD) 848 ± 2084 Mean Taxa Richness (±1 SD) 4 ± 5 Total Number of Taxa 36 Number of Taxa Observed by Taxonomic Group Insects 19 Mollusks 7 Oligochaete Worms 5 Crustaceans 2 Other 3 Percent of Total Abundance by Taxonomic Group © 2016 ESS Group, Inc. Page 2 Benthic Macroinvertebrate Sample Analysis Report – Vermont