Preliminary Assessment Extent (PAE) Arckaringa subregion v03

## **Abstract** \n\nThis dataset and its metadata statement were supplied to the Bioregional Assessment Programme by a third party and are presented here as originally supplied.\n\n\n\nThis dataset was created for the Bioregional Assessment by the Government of South Australia, Department of Environment, Water and Natural Resources. The data presents the approach taken to develop a Preliminary Assessment Extent (PAE) for the Arckaringa subregion. This mapping and geospatial data, represent draft information presented to the Bioregional Assessment Team, which will be amended as required to support the Bioregional Assessment Programme. It is understood that the Arckaringa PAE will be subject to revisions as new ecological, hydrological and hydrogeological information and understandings become available.\n\n## **Dataset History** \n\nThis dataset was created for the Bioregional Assessment by the Government of South Australia, Department of Environment, Water and Natural Resources. See the attached document relating to the methodology and assumptions in PAE development for more information\n\n\n\nThe following methodology was followed to formulate the Arckaringa PAE:\n\n- Extent of potential groundwater drawdown assumed at 210km around coal beds (refer Figure 3), based upon DEWNR conceptual modelling undertaken for the Pedirka Basin (refer Appendix A for summary of modelling methodology). Modelling of the Arckaringa basin is proposed be completed by late 2014 which may affect this assumption. This applied to the north and easterly direction from coal beds within the basin.\n\n- Inferred 210km groundwater drawdown extent assumes potential for up to a 50 year Life of Mine (LOM) and large scale mining operations.\n\n- Western and southern boundaries follow the Great Artesian Basin (GAB) and Arckaringa Basin boundaries taking the further boundary from coal beds to identify potential groundwater connectivity.\n\n- 20km buffer boundary included as a contingency around known surface waters and groundwater drawdown extents.\n\n-10 km buffer included where PAE intersects with fractured rock aquifer (FRA) extents.\n\n- Inclusion of springs in close proximity to 210km radius from coal beds in an easterly direction based upon knowledge of DEWNR groundwater system.\n\n- Entire Lake Eyre (north and south) boundary incorporated (from SA Waterbodies mapping).\n\n- Phreatic surface information (See Figure 5) was utilised to identify connectivity to shallow groundwater potentially utilised by vegetation, which was identified up to a 10m depth, based upon decisions made by the Bioregional Assessment team for other PAEs.\n\n- Tertiary sediments were excluded from consideration as a buffer to the GAB where they intersect with coal deposits as it was assumed direct impact to the tertiary sediments would occur should open cut mining activities occur.\n\nAdditional data sets and assumptions used to derive the PAE and gain an understanding of ecological, hydrological, hydrogeological and mining related features and values include the following:\n\n- Arckaringa basin boundary (DEWNR Dataset), including outlier basin formations excluded from the PAE where outside of the GAB.\n\n- DMITRE Mapped areas of economic coal beds (Coal beds).\n\n- Exploration Licences (EL) as lodged with DMITRE.\n\n- Known watercourses (surface water data) (DEWNR dataset).\n\n- Springs locations (DEWNR dataset + national springs database compiled for the Recovery Plan by Fensham et al. 2005)).\n\n- GAB springs of the Lake Eyre supergroup included with a 5km buffer around the point location to accommodate the extensive wetland and terrestrial ecosystems the spring support. It is noted that the impacts of drawdown on pressures would reduce further from the coal resource but recognising that there may be ecological dependencies between the springs.\n\n- PAE along south-western boundary of Arckaringa Basin based upon extent of drawn down from coal beds with limited groundwater knowledge. Western boundary excluded based on absence of GAB groundwater.\n\n- A potentiometric surface has been generated for the GAB aquifer (Cadna-owie Formation - Algebuckina Sandstone and equivalents) for the SA and NT portions of the GAB.\n\n- Coal Beds outside of Arckaringa Geological Basin are excluded.\n\n- 5km buffer around GAB springs (GAB Springs Database) has been smoothed where appropriate.\n\n- Dry areas of the GAB were excluded as these areas do not have surface water connections with lease areas.\n\n- Potential for mining related water diversions excluded from the assessment.\n\n- Upstream watercourses would be excluded where no direct link from mining, where outside the extent of drawdown.\n\n- That the alluvial groundwater systems are not connected to the GAB\n\n## **Dataset Citation** \n\n"SA Department of Environment, Water and Natural Resources" (2014) Preliminary Assessment Extent (PAE) Arckaringa subregion v03. Bioregional Assessment Source Dataset. Viewed 07 February 2017, http://data.bioregionalassessments.gov.au/dataset/1a27370f-c2c4-48dd-9b7b-d034dd6fee33.

## **摘要**

本数据集及其元数据声明由第三方提供给生物区域评估计划（Bioregional Assessment Programme），此处按原始提供的形式呈现。

本数据集由南澳大利亚州环境、水与自然资源部（Department of Environment, Water and Natural Resources）为生物区域评估计划编制。本数据阐述了为阿卡林加（Arckaringa）子区域编制初步评估范围（Preliminary Assessment Extent, PAE）所采用的方法。此类制图与地理空间数据为提交给生物区域评估团队的草案信息，将根据生物区域评估计划的需求进行修订。据悉，随着新的生态学、水文学与水文地质学信息及认知的获取，阿卡林加PAE将进行修订。

## **数据集历史**

本数据集由南澳大利亚州环境、水与自然资源部为生物区域评估计划编制。如需了解PAE编制过程中的方法与假设，请参阅随附文档。

为划定阿卡林加PAE，采用了以下方法：

- 以针对佩迪尔卡盆地（Pedirka Basin）开展的DEWNR概念模型（详见附录A的模型方法摘要）为依据，假设煤层周边210公里范围为潜在地下水降落漏斗范围（参见图3）。阿卡林加盆地的模型编制计划于2014年底完成，该结果可能会对本假设产生影响。本规则适用于盆地内煤层以北及以东方向。

- 推断的210公里地下水降落范围假设矿山服务年限（Life of Mine, LOM）最长为50年，且为大规模采矿作业场景。

- 西部与南部边界以大自流盆地（Great Artesian Basin, GAB）和阿卡林加盆地的边界为准，选取距煤层更远的边界以识别潜在地下水连通性。

- 在已知地表水及地下水降落范围周边设置20公里缓冲边界作为应急措施。

- 在PAE与裂隙岩含水层（fractured rock aquifer, FRA）范围相交的区域设置10公里缓冲带。

- 根据DEWNR地下水系统的相关认知，将煤层以东210公里半径范围内的邻近泉点纳入评估范围。

- 完整纳入艾尔湖（Lake Eyre，南北湖区）的边界（数据源自南澳水体制图（SA Waterbodies mapping））。

- 根据生物区域评估团队针对其他PAE制定的决策，利用潜水面信息（参见图5）识别与植被可能利用的浅层地下水的连通性，该浅层地下水埋深不超过10米。

- 在第三纪沉积物与煤层相交的区域，将其排除在GAB缓冲范围之外，因为假设露天采矿活动会对第三纪沉积物造成直接影响。

用于推导PAE并了解生态、水文、水文地质及采矿相关特征与价值的附加数据集与假设如下：

- 阿卡林加盆地边界（DEWNR数据集），其中位于GAB以外的孤立盆地地层被排除在PAE之外。

- DMITRE制图的经济煤层（Coal beds）分布区域。

- 向DMITRE提交的勘探许可证（Exploration Licences, EL）。

- 已知河道（地表水数据）（DEWNR数据集）。

- 泉点位置（DEWNR数据集 + Fensham等人2005年为恢复计划编制的全国泉点数据库）。

- 将艾尔湖超群的GAB泉点纳入范围，并在每个泉点位置周边设置5公里缓冲带，以覆盖该泉点支撑的广阔湿地与陆地生态系统。需说明的是，地下水降落对泉点的压力影响会随着与煤层距离的增加而减弱，但需认识到泉点之间可能存在生态依存关系。

- 阿卡林加盆地西南边界的PAE范围基于有限地下水认知下的煤层降落范围划定。由于缺乏GAB地下水数据，西部边界被排除在外。

- 针对GAB在南澳与北领地的部分，为GAB含水层（Cadna-owie组-Algebuckina砂岩及等效地层）生成了测压水面图。

- 阿卡林加地质盆地以外的煤层被排除在外。

- 在适当情况下，对GAB泉点（GAB泉点数据库）周边的5公里缓冲带进行了平滑处理。

- GAB的干旱区域被排除在外，因为这些区域与租赁区域无地表水连通性。

- 评估中排除了采矿相关的水资源调水可能性。

- 若河道位于降落范围以外且与采矿无直接关联，则上游河道被排除在外。

- 假设冲积地下水系统与GAB无连通性。

## **数据集引用**

"南澳大利亚州环境、水与自然资源部"（2014）《阿卡林加子区域初步评估范围（PAE）v03》，生物区域评估源数据集。查阅日期：2017年2月7日，http://data.bioregionalassessments.gov.au/dataset/1a27370f-c2c4-48dd-9b7b-d034dd6fee33。