EFTA01084452.pdf

ASSESSMENT OF IMPACT OF FILL MATERIAL PLACED OFF THE NORTHWESTERN POINT OF THE ISLAND OF LITTLE ST. JAMES INTRODUCTION Bioimpact, Inc. was contracted by LSJ, LLC. to conduct a detailed benthic survey of the area of impact on the northwestern point of the island. The Department of Planning and Natural Resources issued a Notice of Violation on March 8, 2012 in response to findings made by Fish and Wildlife on a December 2011 field visit. In the following report Bioimpact has delineated the area of impact, and documented the impacts which have occurred. The impacts were based on dive surveys and review of existing data and surveys of the shoreline. The changes found on the site are not a result of natural causes. BACKGROUND On March 8, 2012 the Department of Planning and Natural Resources issued a Notice of Violation to Nautilus Inc. The Notice of Violation (NOVA) was in response to findings of a December 8, 2011 site visit by the Division of Fish and Wildlife , the NOVA stated that Fish which found that material had been excavated and disposed of in the nearshore environment. The area in which the fill was placed habitat for Acropora poimato and Acropora cervicornis which are listed species on the Federal Endanger Species List. In 2009 Brian Moseley and Associates conducted a survey comparing the 2009 shoreline to the 2003 shoreline. This survey showed changes in the shoreline between the 2003 and 2009, the 2009 conditions are what is now reflected in the August 18, 2009 Google aerial. An overlay of the aerial and the survey are provided below. Figure 1. The August 18, 2009 survey conducted by Brian Moseley and Associates overlain the August 18, 2009. The blue arrow represents the 2009 shoreline the red arrow the 2003 shoreline as drawn from a 2003 aerial. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 1 EFTA01084452 The 2009 Google aerial is the most recent aerial available on Google Earth and is what is utilized in the following assessment. FINDINGS A survey using a hand held Garmin GPS was utilized to determine the extent of the fill material which extends from the point out along the top of what was a shallow rock outcropping. The fill material consists of riprap boulders, smaller stones and a sandy core area which has been reworked by a backhoe or bulldozer that extends out into the riprap from the previously existing drive. This photograph shows the extent of the fill extending offshore. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 2 EFTA01084453  andy material extends part way out the created groin, which narrows to an all riprap. The northern slope of the riprap is much steeper than the southern and western slopes. his sign is at the base of the slope and is approximately 10ft. from the base of the building. As shown in the large photograph above, the riprap now extends out 140ft. from the sign. GPS readings were taken with a Garmin Hand Held GPS at the sign and at the outer edge of the emergent riprap. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 3 EFTA01084454 GPS readings taken at the site in May 2012. This places the outer edge of the riprap 80ft. from the 2009 shoreline. Because of the sea conditions and that the steepness of the northern riprap face the width of the groin was not accurately measured. From the aerial showing the GPS points above it is apparent that additional material has been placed in the sea. It would appear that somewhere between 1000 and 1250 sq. ft. of benthic habitat was directly impacted by the placement of fill. It appears that the fill material impacted very shallow tidally areas out to a depth between 1' and 18" to the south and to the north the impacts go deeper to as much as a depth of Sft. because of stones falling into the grotto which runs along the point along the point. Dive surveys were conducted in May and June of 2012 to assess the impact of fill. It was fairly rough on all days surveyed but seas did calm sufficiently to allow for a thorough survey. The new fill material is visible different than the older natural and older fill material found farther to the south along the riprap. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 4 EFTA01084455  The older material along the areas where the new material was not deposited have encrusting algae and many of the rocks are worn smooth due to movement in the wave. he new material looks very different, and has not yet become as colonized and has sharper edges. The fill material appears to have been carefully placed rather than dump, which limited the extent of the direct damages. IMPACTS OF THE PLACEMENT OF FILL On the southern side of the jetty there has always been less colonization and therefore impacts to the southern portion of the fill would are not as significant at the areas to the north. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page S EFTA01084456 Approaching the new point along the south side of the fill material there are areas where fire coral extended out from under boulders and in one case a Porites astreoides has survived in a crevice between two boulders. In the southern portion of the groin the new bounders were place on top of areas with abundant boring urchins Echinometra luncter in the rocks, fire coral colonization and scattered small head corals. he Porties amid the boulder indicating that corals were present in this area of the hard bottom where the rocks and riprap were placed. he hard bottom immediately off the end of the new riprap, the last piece of riprap is evident in the left hand corner of the picture. The area has urchins, fire coral and widely scattered corals. This is a good representation of the habitat that existed under the southern portion of the riprap. The northern portion of the riprap extends into an area with much denser colonization. A study was conducted in 2009 and the habitat and Acropora in the area were mapped. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 6 EFTA01084457  Lightly shaded area has dense coral colonizatio as well as a significant amount of habitat - `"structure There are also numerous Acropora pinata and A cervicornis on the crest and rthern slope of the rocky promentory. • nr., 020,8 too Ann 0 Xt. (vow. TnhMOOee imepe 01008 C40 1• 10k4,e Coogic N A e,.1 ,II This figure shows the area of habitat has well as the approximate location of the Acropora colonies The locations of the Acropora overlain the current aerial and are of impact shows that 3 Acropora were directly impacted by the filling activity. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 7 EFTA01084458 The Acropora which were impacted by the placement of fill are shown in red. The 2009 report stated that there numerous Acropora colonies on the northern side of the existing rocky outcropping but not on the southern side. The following photographs are from the 2009 surveys. Acroporo palmate off the point. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 8 EFTA01084459  croporo cervicornis on the northern side of the rocks Acropora cervicornis on the northern side of the rocky outcropping Acropora palmata on the shallow rocks To the north appears that the new riprap was place on top of areas with encrusting fire coral as well as encrusting gorgonians, and hard corals including at least 3 Acroporo. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 9 EFTA01084460  his broken branch of an Acropora palmata lies just off the end of the expanded groin. The branch is putting out new branches but is not attached to the seafloor and is subject to movement. nother broken limb of Acropora at the edge of the new riprap, this fragment is not doing as well. he boulders here are sitting on top of fire coral as well as a Porites ostreoides. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 10 EFTA01084461  orals extending out from under boulders and small stones along the northern edge of the groin. The fill material directly impacted between 1000 and 1250 sq.ft. of coral habitat, the southern portion was sparsely colonized while the crest and northern slope was more heavily colonized. At least 3 Acroporo palmate were directly impacted and the entire area was critical habitat for these species. The hard bottom habitat was also colonized by Porites astreoides, Porites porites, Diploria strigosa, and Millepora spp. There was also some coverage by encrusting gorgonians (Erythropodium cariboeorum) and numerous boring urchins, Echinometra and black urchins, Diadems also colonized the shallow environment. These organisms were denser to the north of the crest than the south. The filling probably also had indirect impacts through the introduction of fines from the riprap and from the sandy fill material which escaped through the rocks. REMEDIATION The removal of the material would most likely result in additional impacts to the surrounding environment through direct impacts to the corals at the edge of the fill material and through the re- suspension of fine sediments released into the water column as the material is removed. We would recommend that mitigation be off site, yet in-kind by protecting additional Acroporo habitat. We recommend the placement of XX public mooring buoys protecting a total of 1250 sq. ft. of coral habitat placed in locations selected by DPNR to protect coral habitat and through the cleanup debris from areas where wrecked vessels have impacted the shallow water environment and the presents of this debris continues to pose a threat to nearby corals as it is moved in the waves. The proposed sites of cleanup are as follows and would protect XXXX sq. ft. of coral habitat. Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 11 EFTA01084462 Impact Assessment Little St. James Northwestern Point Bioimpact, Inc. June 6, 2012 Page 12 EFTA01084463