Ruins build crash

---- Minecraft Crash Report ----
// Oh - I know what I did wrong!

Time: 4/11/13 11:50 AM
Description: Exception getting block type in world

java.lang.UnsupportedOperationException
	at java.util.AbstractCollection.add(AbstractCollection.java:221)
	at java.util.Collections$SynchronizedCollection.add(Collections.java:1577)
	at atomicstryker.ruins.common.RuinsMod.generateSurface(RuinsMod.java:122)
	at atomicstryker.ruins.common.RuinsMod.access$100(RuinsMod.java:37)
	at atomicstryker.ruins.common.RuinsMod$RuinsWorldGenerator.generate(RuinsMod.java:89)
	at cpw.mods.fml.common.registry.GameRegistry.generateWorld(GameRegistry.java:102)
	at net.minecraft.world.gen.ChunkProviderServer.func_73153_a(ChunkProviderServer.java:259)
	at net.minecraft.world.chunk.Chunk.func_76624_a(Chunk.java:1243)
	at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:153)
	at net.minecraft.world.gen.ChunkProviderServer.func_73154_d(ChunkProviderServer.java:166)
	at net.minecraft.world.World.func_72964_e(World.java:522)
	at net.minecraft.world.World.func_72798_a(World.java:407)
	at net.minecraft.world.World.func_72799_c(World.java:431)
	at net.minecraft.world.World.func_72922_b(World.java:378)
	at net.minecraft.world.WorldProvider.func_76566_a(WorldProvider.java:100)
	at net.minecraft.world.WorldServer.func_73052_b(WorldServer.java:834)
	at net.minecraft.world.WorldServer.func_72963_a(WorldServer.java:798)
	at net.minecraft.world.World.<init>(World.java:291)
	at net.minecraft.world.WorldServer.<init>(WorldServer.java:107)
	at WorldServerOF.<init>(WorldServerOF.java:30)
	at net.minecraft.server.integrated.IntegratedServer.func_71247_a(IntegratedServer.java:51)
	at net.minecraft.server.integrated.IntegratedServer.func_71197_b(IntegratedServer.java:138)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:429)
	at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:573)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at java.util.AbstractCollection.add(AbstractCollection.java:221)
	at java.util.Collections$SynchronizedCollection.add(Collections.java:1577)
	at atomicstryker.ruins.common.RuinsMod.generateSurface(RuinsMod.java:122)
	at atomicstryker.ruins.common.RuinsMod.access$100(RuinsMod.java:37)
	at atomicstryker.ruins.common.RuinsMod$RuinsWorldGenerator.generate(RuinsMod.java:89)
	at cpw.mods.fml.common.registry.GameRegistry.generateWorld(GameRegistry.java:102)
	at net.minecraft.world.gen.ChunkProviderServer.func_73153_a(ChunkProviderServer.java:259)
	at net.minecraft.world.chunk.Chunk.func_76624_a(Chunk.java:1243)
	at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:153)
	at net.minecraft.world.gen.ChunkProviderServer.func_73154_d(ChunkProviderServer.java:166)
	at net.minecraft.world.World.func_72964_e(World.java:522)

-- Requested block coordinates --
Details:
	Found chunk: true
	Location: World: (-111,64,249), Chunk: (at 1,4,9 in -7,15; contains blocks -112,0,240 to -97,255,255), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Stacktrace:
	at net.minecraft.world.World.func_72798_a(World.java:407)
	at net.minecraft.world.World.func_72799_c(World.java:431)
	at net.minecraft.world.World.func_72922_b(World.java:378)
	at net.minecraft.world.WorldProvider.func_76566_a(WorldProvider.java:100)
	at net.minecraft.world.WorldServer.func_73052_b(WorldServer.java:834)
	at net.minecraft.world.WorldServer.func_72963_a(WorldServer.java:798)

-- Affected level --
Details:
	Level name: New World
	All players: 0 total; []
	Chunk stats: ServerChunkCache: 15 Drop: 0
	Level seed: 7762395643108021363
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options:
	Level spawn location: World: (0,0,0), Chunk: (at 0,0,0 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 0 game time, 0 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
Stacktrace:
	at net.minecraft.world.World.<init>(World.java:291)
	at net.minecraft.world.WorldServer.<init>(WorldServer.java:107)
	at WorldServerOF.<init>(WorldServerOF.java:30)
	at net.minecraft.server.integrated.IntegratedServer.func_71247_a(IntegratedServer.java:51)
	at net.minecraft.server.integrated.IntegratedServer.func_71197_b(IntegratedServer.java:138)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:429)
	at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:573)

-- System Details --
Details:
	Minecraft Version: 1.5.1
	Operating System: Mac OS X (x86_64) version 10.7.5
	Java Version: 1.6.0_43, Apple Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
	Memory: 398505232 bytes (380 MB) / 581435392 bytes (554 MB) up to 2666921984 bytes (2543 MB)
	JVM Flags: 3 total; -Xbootclasspath/a:/System/Library/PrivateFrameworks/JavaApplicationLauncher.framework/Resources/LauncherSupport.jar -Xms512M -Xmx2560M
	AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Suspicious classes: FML and Forge are installed
	IntCache: cache: 0, tcache: 0, allocated: 3, tallocated: 63
	FML: MCP v7.44 FML v5.1.8.611 Minecraft Forge 7.7.1.611 Optifine OptiFine_1.5.1_HD_U_B2 45 mods loaded, 45 mods active
	mcp [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	FML [Forge Mod Loader] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	Forge [Minecraft Forge] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	CodeChickenCore [CodeChicken Core] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	NotEnoughItems [Not Enough Items] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_bspkrsCore [bspkrsCore] ([1.5.1]bspkrsCorev1.03.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_SparcsDungeonLoot [mod_SparcsDungeonLoot] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	DynamicLights [Dynamic Lights] (DynamicLights_1.5.1.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	DynamicLights_onFire [Dynamic Lights on burning] (DynamicLights_1.5.1.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	DynamicLights_creepers [Dynamic Lights on Creepers] (DynamicLights_1.5.1.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	DynamicLights_dropItems [Dynamic Lights on ItemEntities] (DynamicLights_1.5.1.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	DynamicLights_flameArrows [Dynamic Lights on Flame enchanted Arrows] (DynamicLights_1.5.1.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	DynamicLights_otherPlayers [Dynamic Lights Other Player Light] (DynamicLights_1.5.1.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	DynamicLights_thePlayer [Dynamic Lights Player Light] (DynamicLights_1.5.1.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	GuiAPI [GuiAPI] (GuiAPI-0.15.4-1.5.1.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	TreeCapitator [TreeCapitator] ([1.5.1]TreeCapitator.Forge.1.5.1.r01.Uni.CoreMod.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	Atum [Atum] (Atum 0.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	BiomesOPlenty [Biomes O' Plenty] (Biomes-O-Plenty-0.5.0.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	CustomSpawner [DrZhark's CustomSpawner] (CustomMobSpawner 1.12.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	MoCreatures [DrZhark's Mo'Creatures Mod] (DrZharks MoCreatures Mod v5.0.7.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	GW_DungeonMobs [Dungeon Mobs] (Dungeon Mobs v2.3.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	ExtrabiomesXL [ExtrabiomesXL] (ExtrabiomesXL-universal-1.5.1-3.12.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	ForgottenNature [Forgotten Nature] (ForgottenNature_v1.2.8.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	Herbology [Herbology] (Herbology_v1.0.1) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	JumpPad++ [JumpPad++] (JumpPad++ R14_2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_playerEnchantments [mod_playerEnchantments] (Mod_MorePlayerEnchantments.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	PrimitiveMobs [PrimitiveMobs] (PrimitiveMobsv1.3.5MC1.5.1.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	AS_Ruins [Ruins Spawning System] (Ruins_1.5.1.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	SimpleOres [SimpleOres] (SimpleOres 1.5.1_1.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_SmartMoving [Smart Moving] (Smart Moving Universal for ModLoader or Minecraft Forge or MCPC+.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_SmartRender [Smart Render] (Smart Moving Universal for ModLoader or Minecraft Forge or MCPC+.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	SpecialMobs [Special Mobs] (SpecialMobs 2.4.2 for MC 1.5.1.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	Stackie [Stackie] (Stackie-universal.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	TorchLevers [Torch Levers] (TorchLeversV1.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	UndergroundBiomes [Underground Biomes] (UndergroundBiomes 1.5.1 - 0.3.4a.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	AS_UpdateCheck [AtomicStryker Update Check Mod] (UpdateCheckerMod_1.5.1.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_DirectionHUD [DirectionHUD] ([1.5.1]DirectionHUDv1.10.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	GrimoireGaia2 [Grimoire of Gaia 2] ([1.5.1]GrimoireofGaia2 1.2.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_IngameInfo [IngameInfo] ([1.5.1]IngameInfo.ML.1.5.1.r01.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_StatusEffectHUD [StatusEffectHUD] ([1.5.1]StatusEffectHUDv1.9.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	mod_WorldStateCheckpoints [WorldStateCheckpoints] ([1.5.1]WorldStateCheckpoints.ML.1.5.1.r01.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	coralmod [CoralReef Mod] (coral-reef-1.5.1-universal.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	IronChest [Iron Chest] (ironchest-universal-1.5.1-5.2.2.351.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	lloverlay [Light Level Overlay] (lloverlay_v0.10-mc1_5_1-forge.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	TwilightForest [The Twilight Forest] (twilightforest-1.17.1.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available
	Profiler Position: N/A (disabled)
	Player Count: 0 / 8; []
	Type: Integrated Server (map_client.txt)
	Is Modded: Definitely; Client brand changed to 'forge,fml'