Supplemental Study for Year 3 Project Completed

Reason for Supplemental Study  Accelerate new lines of research which were identified in August 1999 during the deliberations concerning a ban on CCA in Minnesota

Tasks Assoc. with Supplemental Funds In-Service Issues Disposal Literature Review  Depletion of Cr, Cu, and As during the service life of CCA- treated wood (task 1)  Quantity of CCA-treated wood used by major industries (task 2)  TCLP and SPLP tests for unburned CCA-treated wood (task 5)  Laboratory Methods for Cr and As speciation (task 3)  Identify laboratory methods for organics analysis assoc. with alternative chemicals (task 4)

Task 5: TCLP and SPLP Tests on Unburned CCA-Treated Wood

CCA-Treated Wood and Mulch Leaching Tests

Leaching Tests on Unburned CCA-Treated Wood in Year 3 Supplemental Project  Leaching of new CCA-treated wood using standardized regulatory leaching tests  Leaching of wood mulch produced by C&D debris recycling operations

Leaching of new CCA-treated wood using standardized regulatory leaching tests

Types of Leaching Tests  Batch Tests  Toxicity Characteristic Leaching Procedure (TCLP)  Synthetic Precipitation Leaching Procedure (SPLP)  Column Tests  Field Tests

Testing Results to be Discussed  Ten samples of CCA-treated wood purchased from home supply stores  TCLP  SPLP  Particle Size  One sample  TCLP, SPLP, EP, WET, MEP

Reminder for Arsenic  Toxicity Characteristic  Arsenic: 5 mg/l  Chromium: 5 mg/l  Groundwater Cleanup Target Level  Arsenic: 0.05 mg/l  Chromium: 0.10 mg/l  Copper: 1 mg/l

How are TCLP and SPLP Tests Applied?  TCLP: To determine if solid waste is hazardous by toxicity characteristic. Note: Discarded arsenical- treated wood is exempt under RCRA.  TCLP: To determine is hazardous wastes can be land disposed.  SPLP: To determine if land-applied waste or contaminated soil presents a risk to groundwater from chemical leaching.

TCLP and SPLP Batch tests. TCLP: Municipal Landfill SPLP: Acidic Rain 100 g of waste per 2 L of leaching solution. Extracted for 18 hours. Leachate if filtered and analyzed.

Leaching Tests  10 samples of new CCA-treated dimensional lumber were collected from retail outlets  The wood was processed into 4 different sizes  TCLP and SPLP performed on all samples  Additional leaching tests (EP Tox, MEP, WET) were performed on one sample.

Figure IV.3: SPLP Extraction Results for As, Cu, and Cr from Saw Dust

Figure IV.6: SPLP Extraction Results for As, Cu, and Cr from 1, 100-g Block

Figure IV.7: TCLP Extraction Results for As, Cu, and Cr from Sawdust

Figure IV.10: TCLP Extraction Results for As, Cu, and Cr from 100-g Block

Figure IV.11: Arsenic Concentration in Extracts from TCLP, SPLP, EPTOX, and WET

Figure IV.14: MEP Test Results for Arsenic, Copper, and Chromium Using 3 20-g Blocks

Implications of Leaching Tests  Without the exclusion, CCA-treated wood would often be a characteristic hazardous waste.  If SPLP results are compared to GWCTLs, should not be disposed in an unlined landfill (based on current policy for other wastes).

What About Reuse Outside the Landfill (wood mulch)?

Mulch Bagging Operation

Leaching from Land Applied Mulch  SPLP was performed on samples of processed wood from C&D debris recycling facilities  SPLP was also performed on several samples of other mulches, including commercial colored mulch

Table IV.7: Samples Exceeding the GWCTL

Implications for Mulch  When considering SPLP leaching, CCA- treated wood must be present at levels of less than 1% in wood mulch to meet current groundwater standards.  Most C&D wood samples are already greater than 1%.

Questions?

Task 2: Major Use Sectors

Objectives  Estimate the distribution of CCA within different use sectors  Production & disposal by product type  Total amount of As currently in service  Breakdown use – U.S. Statistics - Florida Statistics (utility poles/docks)

Production and Disposal By Product Type (Florida)

Amount of As Currently In Service Florida Statistics

28,600 tons of As, Cumulative  1600 tons As imported per year In-service losses (10%): 2900 tons Disposed to date: 1600 tons Future disposal (for that imported through 2000): 24,100 tons

U.S. Southern Pine Markets (From SFPA) 36% 8%15% 18% 10% From SFPA

Florida Use Statistics  Focus  Utility Poles  Docks (Marine & Freshwater)

Utility Poles

Residential Docks  Evaluated data for 3 counties (Alachua, Dade and Leon)

Material distribution in Alachua County Docks Predominantly Freshwater Docks

Material distribution in Leon County Docks Predominantly Freshwater Docks

Material distribution in Dade County Docks Predominantly Salt water Docks

Results

Conclusions  Majority of wood sold in the form of lumber & timbers  Disposal of lumber & timbers should peak by 2020  Disposal of utility poles not yet observed in significant quantities -- >Current pole recycling/reuse operations will not be likely able to handle the decommissioning of major lines

Conclusions (con’d)  Amount of arsenic currently in service due to CCA is 26,800 tons (estimated)  This quantity can significantly impact water & soil if not disposed properly.  Management plan needed to recover as much of the As as feasible.

Conclusions (con’d)

Task 1: Depletion During Service Life

Methods  Literature Review  Sample Soils Below CCA-Treated Decks  Analyze Soil Samples

Task 1: Depletion During Service Life  A total of nine decks sampled  3 in Gainesville  3 in Miami  2 in Tallahassee (1 other deck sampled, not CCA-treated)  Samples collected in a grid-like fashion below each deck  Initially, at least 2 background samples were collected near each deck. Later, a total of 8 were collected  A core sample  sawdust collected (to confirm CCA retention) Sample soils below CCA-Treated Decks

Gainesville Decks Paynes Prairie Foot Bridge at NW 34th St Bivens Arm Park

Miami Decks A.D. Barnes Park Oleta River Park Tropical Park

Tallahassee Decks Lake Talquin Tom Brown Park Maclay Gardens

Sampling Grid

Soil Core

Stains, wood bore, & Sawdust XRF Analysis by Robbins Manufacturing

Deck Retention Levels

Grain Size Analysis

Volatiles vs. As concentration

Percent volatile vs. As conc

Metal Concentrations in Soil Under Sampled Decks

Arsenic Concentrations in Soil Under Sampled Decks

Background Information  The Florida Department of Environmental Protection has developed a set of risk-based concentration levels of chemicals in soil: The Soil Cleanup Target Levels (SCTL)  Direct Exposure  Residential SCTL for As is 0.8 mg/kg.  Industrial SCTL for As is 3.7 mg/kg.

Background Information  The naturally occurring As concentration in Florida soils has been measured (Ma et al. 1999).  Geometric Mean = 0.42 mg/kg  73% of soil samples were less than 0.8 mg/kg  >90% of soil samples were less than 3.7 mg/kg

Table II.2: Arsenic Results for Surface Soils 1 BDL=Below Detection Limit. Detection limit is 0.25 mg/kg based on sample dry mass of 2.0 g 2 Does not include results from Lake Talquin, LT, deck

Figure II.1: Comparison of Mean Deck Arsenic Soil Concentration versus Control Soil Concentrations

Figure II.3: Comparison of Mean Deck Soil Chromium Concentration versus Control Soil Concentrations

Figure II.5: Comparison of Mean Deck Soil Copper Concentration versus Control Soil Concentrations

Figure II.10: Average of Soil Cores (As only)

Figure II.11: Log of Arsenic Concentrations

Areal Extent of Potential Impact  An estimate of the area of soil impacted by CCA-treated decks was performed (see page 28).  Approximate 25,000 acres of Florida land covered by CCA-treated decks (39 square miles).  Top 8 inches of this area would correspond to 60 million tons of soil.

Potential Soil Arsenic Concentrations Under Decks

Questions?

Draft of Final Report  Available at  Comments to be accepted through January 21, 2001

Questions?