Arsenic removal from the former Hakalau Plantation Pesticide Mixing Site (aka Poison Mixing Shed and Seed Dipping Facility) on Hakalau Point:
During a County Finance Committee hearing on June 2, 2016, Steve Shropshire, principal of the Shropshire Group, LLC, which owns Hakalau Point, described the arsenic contamination at the site:
You may know that this is one of the highest concentrations of arsenic on the island and maybe the State. It was the result of a seed dipping facility...part of the Hakalau Plantation Infrastructure. (video segment from 30:43-31:06)
Details on the final cleanup action, including a summary of public comments, can be found in the Final Removal Action Report prepared by Integral Consulting Group for the Hawai`i Department of Health, dated June 18, 2014. Included below is an excerpt from the conclusions and recommendations:
Four removal action alternatives (plus the No Action alternative) were evaluated in term of effectiveness, implementability, and cost. Alternative 5, Consolidation and Capping of Arsenic Category C and D Soils at Source Area ("Capping in Place"), was determined to be the optimal remedy. All other alternatives (2, 3 and 4) included significant excavation of arsenic-impacted soils from within the 40-ft shoreline setback adjacent to the cliff face, and were determined to be technically infeasible due to slope stability concerns. Upon approval of the recommended removal action alternative by HDOH, a removal action work plan will be prepared to provide design specifications and guidance in implementing the proposed remedy. (p. 8-1)
Background:
The 1956 Sanborn Map below shows the location of the Poison Mixing Shed on Hakalau Point.
The figure below illustrates the plan for "Capping in Place". Soil from areas of higher concentration of arsenic contamination will be consolidated in the area of highest concentration of contamination, i.e., the location of the former Poison Mixing Shed.
Below, the photo on the left shows the location of the poison mixing shed, the area of highest arsenic concentration. The photo on the right below illustrates the instability of the cliffs.
Aerial photo from 1967 showing the Poison Mixing Shed. Photo courtesy of Cal Motoda.
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July 2014 posting of Hakalau Point showing cliff failure in area of highest arsenic concentration. Actual date the photo was taken is unknown. Accessed via vimeo.com/100024063
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Periodic Updates on Arsenic Remediation at Hakalau Point
On December 27, 2017, the Planning Director approved an SMA Minor Permit for the landowner of Hakalau Point to consolidate and resubdivide two lots into two lots and establish a distillery, food manufacturing and processing operation, watchman's quarters, brewery, tasting room, restaurant, and related improvements including fencing of the arsenic contamination area, landscaping, and the "as-built" carport, as presented in SAA 17-001574, subject to the applicant's compliance with the conditions of approval. Two of the conditions attached to this Minor Permit are related to the arsenic remediation:
November 7, 2019 the County Department of Planning acknowledged HDOH HEER clarification related to compliance with Condition No. 7. Specifically, the landowner must complete the following prior to the issuance of a Certificate of Occupancy:
December 27, 2019 the Hawaii State Department of Health approved the final remediation implementation work plan presenting the actions to be taken for the protection of human health and the environment over a portion of the Former Pepeʻekeo Sugar Company property identified by Tax Map Key (3) 2-9-002:079 and 081, and located at 29-2306 Old Māmalahoa Highway, Hakalau, Hawaiʻi. The plan outlines the actions to be taken to satisfy the requirements of Condition 6, identified in a July 12, 2018 letter from the Hawaii Department of Health (HDOH) Hazard Evaluation and Emergency Response (HEER) Office to the Hawaiʻi County Planning Department (State of Hawaiʻi Department of Health, 2018). These actions include:
- Condition 6: Prior to applying for Plan Approval, the landowner is required to submit a copy of the approved Hawaii Department of Health Hazard Evaluation & Emergency Response (HDOH HEER) Remediation Implementation Work Plan that addresses soil arsenic contamination.
- Condition 7: Prior to issuance of the Certificate of Occupancy, the landowner must submit HDOH HEER documentation that the proposed remedy has been completed. Further, lead contamination remediation, if applicable, must also be documented.
November 7, 2019 the County Department of Planning acknowledged HDOH HEER clarification related to compliance with Condition No. 7. Specifically, the landowner must complete the following prior to the issuance of a Certificate of Occupancy:
- Soil testing for lead and arsenic contamination around the perimeter of Warehouse B (north Warehouse) foundation, as well as soil arsenic contamination testing in the open areas around Warehouse B (west of the fenced-off area) will be completed, under an HDOH-approved sampling plan. This soil testing will include delineation to the depth of soil anticipated to be disturbed, removed, or otherwise impacted during (or following) planned actions under the SMA Minor Permit No. 17-000378. In addition, if this testing reveals soil contamination above applicable HDOH action levels, appropriate cleanup action will be conducted and completed.
- Regarding any other potential planned uses related to SMA Minor Permit No. 17-000378 that are makai (east) of both Warehouses A & B and outside the fenced off area, HDOH would require that appropriate additional definitive confirmation testing be conducted in those areas to document that soil contaminants are well below applicable HDOH action levels. Until such final confirmation sampling is conducted, these presumed uncontaminated or very low risk areas (based on previous testing) outside the fenced-off area should remain in sod/grass cover (i. e. no bare soil exposed).
December 27, 2019 the Hawaii State Department of Health approved the final remediation implementation work plan presenting the actions to be taken for the protection of human health and the environment over a portion of the Former Pepeʻekeo Sugar Company property identified by Tax Map Key (3) 2-9-002:079 and 081, and located at 29-2306 Old Māmalahoa Highway, Hakalau, Hawaiʻi. The plan outlines the actions to be taken to satisfy the requirements of Condition 6, identified in a July 12, 2018 letter from the Hawaii Department of Health (HDOH) Hazard Evaluation and Emergency Response (HEER) Office to the Hawaiʻi County Planning Department (State of Hawaiʻi Department of Health, 2018). These actions include:
- Install a secure fence around the existing ‘arsenic contamination area’ (former pesticide storage and mixing area) identified as contaminated or potentially contaminated in previous testing, to prevent public access. The specific boundary of the fenced off area to be approved by the HDOH HEER Office. Appropriate signage indicating no public access due to contaminated soils will be posted on the fence in multiple locations that are clearly visible upon approach. See the red outline in the map below.
- Conduct representative soil sampling for arsenic contamination along the fishing access trail location on the bounds of the fenced-off contaminated area to confirm soil arsenic levels are below applicable HDOH action levels. If this testing reveals soil contamination above applicable HDOH action levels, either the fenced off area will be expanded to include all the area found to be contaminated (and the fishing trail relocated), or appropriate action will be conducted and completed to remove the soil contamination from the area outside the fence. See the fuschia outline in the map below.
June 22, 2020 - The Department of Health has expanded its online resources. Included in this effort is updated HEER Office website with a helpful section devoted to arsenic contamination:
A series of arsenic fact sheets supply useful information:
- Arsenic in Hawaiian Soils: Questions and Answers on Health Concerns Fact Sheet: https://health.hawaii.gov/heer/files/2019/10/Arsenic-in-Hawaiian-Soils-Questions-and-Answers-on-Health-Concerns-2018.pdf
- Arsenic in Canec Ceilings and Wallboard in Hawai‘i Fact Sheet: https://health.hawaii.gov/heer/files/2019/10/Arsenic-in-Canec-Ceilings-and-Wallboard-in-hawaii-2018.pdf
- Homeowners Guide to Soil Testing for Arsenic: https://health.hawaii.gov/heer/files/2019/10/Homeowners-Guide-to-Soil-Testing-for-Arsenic-2008.pdf
The Department of Health now has an on-line database of HEER sites and documents that are publicly available. The site is called iHEER, and here is a link to related to Hakalau Point: