Closure Plan Research Articles

CLOSURE PLAN EVALUATION FOR RISK OF ACID ROCK DRAINAGE

Control of acid rock drainage (ARD) is a long-term issue for many mine sites and is often a primary objective of remediation efforts. Some sites continue to require monitoring and management of ARD long after mine operation has ceased and closure is complete. In New Zealand, an innovative and quantitative approach was applied to evaluate the expected risk of ARD after implementation of the closure plan for the Golden Cross Mine. In addition, this future risk was compared to current operating conditions to provide an estimate of the reduction in risk provided by the remediation activities. This approach was useful to both the mine proponent and the regulatory agencies in assessing the effectiveness of the existing closure plan and providing focus on the components of greatest risk. Mine components remaining on site after closure that could potentially generate ARD under various failure scenarios were identified and evaluated. These components included the tailings decant pond, waste rock, stockpiles, open pit mine and water treatment systems. For each component, a series of initiating events and failure scenarios were identified, and a decision tree methodology was utilized to estimate the probability of ARD generation for both current and closure conditions. Due to themore » implementation of closure plans designed to minimize or eliminate ARD through regarding, construction of engineered covers and water management designs, the risk of ARD generation will be significantly reduced over time.« less

Integrated environmental management and planning for closure: The challenges

Abstract This article provides a framework for the collection of papers on integrated environmental management through planning for closure from the outset. It provides an overview of the environmental impacts of mining and underlines the imperative of improved environmental management and planning. It argues that pollution prevention, through planning for closure, from the outset can lead to cost effective strategies for operationalising sustainable minerals development. This seems to be most true for greenfield sites since, generally, the earlier closure planning and pollution prevention is built into a project, the more cost‐effective and environmentally benign closure will be. Furthermore, for greenfield sites, pollution prevention techniques can be employed from the outset, at the stages of exploration and mine development, and then monitored and improved through the operation stage to closure. The article then discusses how global changes in the industry, following the liberalisation of investment r...

Trends In Regulatory Acceptance Of Risk‐Based Cleanup Goals And Natural Attenuation For Site Closure

AbstractSince 1994, there has been a significant regulatory shift toward risk‐based cleanup standards based on the site‐specific risk of the more toxic and mobile compounds; namely, benzene, ethyl benzene, toluene, and xylene (BTEX). This regulatory shift has been accompanied by a growing acceptance of natural attenuation as an important component of petroleum site remediation. This article briefly reviews regulatory progress toward risk‐based remediation and describes the successful application of risk‐based corrective actions (RBCAs) at two fuel contaminated sites on Air Force installations. By developing site‐specific cleanup goals, and combining natural attenuation, source reduction, and land use controls, innovative risk‐based closure plans have been implemented on these sites.

Health organisations welcome new group to vet hospital closure plans

Health organisations welcome new group to vet hospital closure plans

DESIGN, PERMITTING, AND CONSTRUCTION ISSUES ASSOCIATED WITH CLOSURE OF THE PANNA MARIA URANIUM TAILINGS IMPOUNDMENT

In 1992, Panna Maria Uranium Operations (PMUO) initiated licensing and engineering activities for closure of the Panna Maria mill and 150-acre tailings impoundment located in southeast Texas. Closure of the tailings impoundment is permitted by license amendment through the Texas Natural Resources Conservation Commission (TNRCC), and based on closure criteria outlined in Texas regulations. The closure plan for the Panna Maria tailings impoundment was submitted for Texas regulatory agency review in April 1993, with details of the closure plan modified in 1994, 1995, and 1996. The closure plan included a multi-layered cover over the regraded tailings surface which was designed for long-term isolation of tailings, reduction of radon emanation to regulated levels, and reduction of infiltration to TNRCC-accepted levels. The cover and embankment slope surfaces and surrounding areas were designed to provide acceptable erosional stability as compared to runoff velocities from the Probable Maximum Precipitation event. Cover materials were selected from on-site materials and evaluated for suitability based on permeability, radon attenuation, and soil dispersivity characteristics. Off-site materials were used when necessary. The cover over the tailings has a maximum slope of 0.5 percent, and the regraded embankment slopes outside the perimeter of the impoundment have a maximum slope ofmore » 20 percent. All reclaimed slopes are covered with topsoil and revegetated. A riprap-lined channel is to be used to convey runoff from within the perimeter of the reclaimed impoundment to the north of the impoundment.« less

Review of 23 years of STD: Island Copper Mine, Canada : D. V. Ellis, T. F. Pedersen, G. W. Poling, C. Pelletier & I. Horne, Marine Georesources & Geotechnology, 13(1–2), 1995, pp 59–99

The submarine tailings disposal (STD) system at Island Copper Mine has been subjected to a comprehensive environmental monitoring program initiated in 1970, some 20 months before the mill started processing ore. The program has been extended and modified as new factors became relevant or it became clear that particular factors were not of concern at this site. The major environmental issues have concerned (1) tailings resuspension and upwelling, (2) smothering of benthos, and (3) trace metal contamination from acid rock drainage (ARD). A closure plan has been prepared for implementation in 1995. Tailings were resuspended and upwelled to surface close to the fiord sill due to unpredicted periodic high‐density tidal jets scouring the deposits at that point. The localized elevated turbidity has not affected biological productivity. Benthos have been smothered under rapid tailings deposition such that areas under thick tailings ( > about 20–30 cm) showed reduced biodiversity. At deposition rates of < l cm p.a...

State permit certification requirements examined

AbstractNearly all of the myriad federal environmental statutes that have been passed have included waivers of sovereign immunity. In order for federal practitioners to understand the nature of these waivers, and how extensive they are, it is important to understand the history of waivers by viewing them through the Supreme Court's interpretation of what is required for Congress to yield federal control to the states with respect to federal facilities.One area in which further exploration is necessary is states requiring professional engineers or registered engineers to certify permit applications or closure plans in accordance with state permit laws and regulations, in environmental fields as these laws and regulations apply to federal facilities. This issue is further complicated when the program has been given delegated authority by EPA. What is the effect of a program that has not been approved by EPA but still regulates an environmental area that will have a significant effect on a federal facility with respect to this same requirement?

Concern raised over Belfast closure plans

Concern raised over Belfast closure plans

Closure plan condemned as a disgrace

Closure plan condemned as a disgrace

RCN concerned about closure plans.

Plans to close six colleges of nursing in Northern Ireland and replace them with two educational institutes by the end of June have sparked concerns from the RCN. The Northern Ireland National Board claims the restructuring is due to the decline in student numbers.

On the neutralization of acid rock drainage by carbonate and silicate minerals

The net result of acid-generating and-neutralizing reactions within mining wastes is termed acid rock drainage (ARD). The oxidation of sulfide minerals is the major contributor to acid generation. Dissolution and alteration of various minerals can contribute to the neutralization of acid. Definitions of alkalinity, acidity, and buffer capacity are reviewed, and a detailed discussion of the dissolution and neutralizing capacity of carbonate and silicate minerals related to equilibium conditions, dissolution mechanism, and kinetics is provided. Factors that determine neutralization rate by carbonate and silicate minerals include: pH, PCO2, equilibrium conditions, temperature, mineral composition and structure, redox conditions, and the presence of “foreign” ions. Similar factors affect sulfide oxidation. Comparison of rates shows sulfides react fastest, followed by carbonates and silicates. The differences in the reaction mechanisms and kinetics of neutralization have important implications in the prediction, control, and regulation of ARD. Current static and kinetic prediction methods upon which mine permitting, ARD control, and mine closure plans are based do not consider sample mineralogy or the kinetics of the acid-generating and-neutralizing reactions. Erroneous test interpretations and predictions can result. The importance of considering mineralogy for site-specific interpretation is highlighted. Uncertainty in prediction leads to difficulties for the mine operator in developing satisfactory and cost-effective control and remediation measures. Thus, the application of regulations and guidelines for waste management planning need to beflexible.

Review of 23 years of STD: Island copper mine, Canada

The submarine tailings disposal (STD) system at Island Copper Mine has been subjected to a comprehensive environmental monitoring program initiated in 1970, some 20 months before the mill started processing ore. The program has been extended and modified as new factors became relevant or it became clear that particular factors were not of concern at this site. The major environmental issues have concerned (1) tailings resuspension and upwelling, (2) smothering of benthos, and (3) trace metal contamination from acid rock drainage (ARD). A closure plan has been prepared for implementation in 1995. Tailings were resuspended and upwelled to surface close to the fiord sill due to unpredicted periodic high‐density tidal jets scouring the deposits at that point. The localized elevated turbidity has not affected biological productivity. Benthos have been smothered under rapid tailings deposition such that areas under thick tailings ( > about 20–30 cm) showed reduced biodiversity. At deposition rates of < l cm p.a...

Unions attack Scottish closure plans

Unions attack Scottish closure plans

News

A three-day candlelit vigil was held in St James' Church in Piccadilly as part of a campaign to halt the threatened closure of London's Royal Marsden Hospital. Campaigners, led by actress Fiona Fullerton, also delivered a massive petition bearing 900,000 signatures to Downing Street in protest at the closure plans. Yona Zalosor (second from left), a former patient at the hospital. Ls shown with three members of the Marsden Patients Action Group. From left: Melissa Bennett. Philip Wood and Jenny Bennett.

Duty of UK health authority to consult over closure plans

Duty of UK health authority to consult over closure plans

Mixed reaction to revised London hospital closure plan.

Nursing unions have given a mixed response to government plans for health services in London, which propose the closure of at least five hospitals in the capital and about 2,500 beds.

Residential care provision in mental health: The current picture and future uncertainties

A survey was undertaken of all residential facilities for adults with mental health problems within a sample of 35 UK district health authorities. Although the private sector was found to be the largest single provider for this client group, health authorities were beginning to provide a significant number of places in residential and nursing home facilities. Many of these were being developed jointly with housig associations and other voluntary agencies, as is encouraged by the current financial benefits. Health authority-initiated provision was found to be associated with hospital closure plans, but the survey suggests that the private sector is not currently involved in local planning. Uncertainties about future funding arrangements under the NHS and Community Care Act (1990) raise questions about the future coordination and funding of hospital closure programmes.

The TAPS project. 16: Difficult to place, long term psychiatric patients: risk factors for failure to resettle long stay patients in community facilities.

To identify patients who could not be resettled in the community as part of the closure plans of two psychiatric hospitals and to determine their numbers and risk factors for failure. Prospective study of the closure of Friern and Claybury psychiatric hospitals. The first third (369) of long stay psychiatric patients to be resettled. Reasons for patients being readmitted to hospital and not leaving the patients' service needs. 22--6% of both hospitals' long stay patients--were not successfully resettled in the community. Eighteen continuing care places per 100,000 of catchment area population seem to be required for this group. Patients whose placements were unsuccessful were usually readmitted because of a deterioration of their mental state and aggressive behaviour, both of which persisted and necessitated their continuing stay in hospital, often in a locked ward. Risk factors associated with failure were a high level of psychosis; a diagnosis of paranoid psychosis; incontinence; and being male. But having a social network, especially a large one, seemed to aid successful placement in the community. Rehabilitation efforts should be focused on the characteristics of these patients that put them at risk of failing to succeed in community placements.

Nurses’ unions pledge to fight London hospital closure plan

Nurses’ unions pledge to fight London hospital closure plan

7,000 protest against Irish closure plans

7,000 protest against Irish closure plans