java.lang.NullPointerException: Exception ticking world
    at biomesoplenty.common.block.BlockBOPGrass.func_149688_o(BlockBOPGrass.java:139)
    at nightkosh.gravestone_extended.structures.catacombs.components.CatacombsBaseComponent.fillDownwards(CatacombsBaseComponent.java:142)
    at nightkosh.gravestone_extended.structures.catacombs.components.Mausoleum.addComponentParts(Mausoleum.java:129)
    at nightkosh.gravestone_extended.structures.catacombs.CatacombsSurface.buildMausoleum(CatacombsSurface.java:63)
    at nightkosh.gravestone_extended.structures.catacombs.CatacombsSurface.build(CatacombsSurface.java:31)
    at nightkosh.gravestone_extended.structures.catacombs.CatacombsSurface.<init>(CatacombsSurface.java:27)
    at nightkosh.gravestone_extended.structures.catacombs.CatacombsGenerator.generate(CatacombsGenerator.java:40)
    at nightkosh.gravestone_extended.structures.GraveStoneWorldGenerator.generateSurface(GraveStoneWorldGenerator.java:39)
    at nightkosh.gravestone_extended.structures.GraveStoneWorldGenerator.generate(GraveStoneWorldGenerator.java:31)
    at net.minecraftforge.fml.common.registry.GameRegistry.generateWorld(GameRegistry.java:167)
    at net.minecraft.world.chunk.Chunk.func_186034_a(Chunk.java:1016)
    at net.minecraft.world.chunk.Chunk.func_186030_a(Chunk.java:987)
    at net.minecraft.world.gen.ChunkProviderServer.func_186025_d(ChunkProviderServer.java:157)
    at net.minecraft.server.management.PlayerChunkMapEntry.func_187268_a(PlayerChunkMapEntry.java:126)
    at net.minecraft.server.management.PlayerChunkMap.func_72693_b(SourceFile:147)
    at net.minecraft.world.WorldServer.func_72835_b(WorldServer.java:227)
    at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:754)
    at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:396)
    at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:666)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:524)
    at java.lang.Thread.run(Thread.java:748)